Edible oils derived from aquatic products are rich in lipids beneficial to human health.However,the volatile flavor characteristics of flesh oil and liver oil from Doederleinia berycoides remain unclear.In this study,...Edible oils derived from aquatic products are rich in lipids beneficial to human health.However,the volatile flavor characteristics of flesh oil and liver oil from Doederleinia berycoides remain unclear.In this study,flesh oil and liver oil were extracted from Doederleinia berycoides,revealing different fatty acid compositions and contents.Lipidomics analysis identified a total of 124 differential lipids between the flesh oil and liver oil,including 42 glycerophospholipids(GPs),33 glycerolipids(GLs),23 free fatty acids(FAs),13 sphingolipids(SPs),10 sterols(STs),and 3 prenol lipids(PRs).Analysis using HS-GC-IMS identified 12 key volatile compounds that significantly contributed to the distinct volatile flavors of the flesh and liver oils.The volatile flavors originated from these volatile compounds,which had different Relative Odor Activity Values(ROAVs).Further results from HSSPME-GC-MS showed that the volatile flavors of the flesh oil and liver oil were respectively attributed to 64 and 35 volatile compounds,each with unique key volatile compounds exhibiting different ROAVs.There were significant positive or negative correlations between 18 key differential lipids and 24 volatile compounds in both flesh oil and liver oil.Therefore,the complex lipid profiles are responsible for the unique volatile flavors of flesh oil and liver oil,and the differential lipids play a central role in their volatile flavor formation.These findings provide a foundation for understanding the volatile flavor differences in fish oils and hold promise for further exploration of the molecular mechanisms underlying oil volatile flavors.展开更多
Cyclic volatile methyl siloxanes(cVMSs)are widely used in industrial and consumer products because of their thermal stability,low reactivity,and reduced surface tension[1].Their extensive use has resulted in environme...Cyclic volatile methyl siloxanes(cVMSs)are widely used in industrial and consumer products because of their thermal stability,low reactivity,and reduced surface tension[1].Their extensive use has resulted in environmental pollution globally.Recognized as very persistent and very bioaccumulative(vPvB),compounds such as octamethylcyclotetrasiloxane(D4),decamethylcyclopentasiloxane(D5),and dodecamethylcyclohexasiloxane(D6)are regulated in the European Union[2]and are monitored worldwide.展开更多
Emission characteristics of biogenic volatile organic compounds(BVOCs)from dominant tree species in the subtropical pristine forests of China are extremely limited.Here we conducted in situ field measurements of BVOCs...Emission characteristics of biogenic volatile organic compounds(BVOCs)from dominant tree species in the subtropical pristine forests of China are extremely limited.Here we conducted in situ field measurements of BVOCs emissions from representative mature evergreen trees by using dynamic branch enclosures at four altitude gradients(600-1690ma.s.l.)in the Nanling Mountains of southern China.Composition characteristics as well as seasonal and altitudinal variations were analyzed.Standardized emission rates and canopyscale emission factors were then calculated.Results showed that BVOCs emission intensities in the wet season were generally higher than those in the dry season.Monoterpenes were the dominant BVOCs emitted from most broad-leaved trees,accounting for over 70%of the total.Schima superba,Yushania basihirsuta and Altingia chinensis had relatively high emission intensities and secondary pollutant formation potentials.The localized emission factors of isoprene were comparable to the defaults in the Model of Emissions of Gases and Aerosols fromNature(MEGAN),while emission factors of monoterpenes and sesquiterpenes were 2 to 58 times of those in the model.Our results can be used to update the current BVOCs emission inventory in MEGAN,thereby reducing the uncertainties of BVOCs emission estimations in forested regions of southern China.展开更多
VOCs(Volatile organic compounds)exert a vital role in ozone and secondary organic aerosol production,necessitating investigations into their concentration,chemical characteristics,and source apportionment for the effe...VOCs(Volatile organic compounds)exert a vital role in ozone and secondary organic aerosol production,necessitating investigations into their concentration,chemical characteristics,and source apportionment for the effective implementation of measures aimed at preventing and controlling atmospheric pollution.FromJuly to October 2020,onlinemonitoringwas conducted in the main urban area of Shijiazhuang to collect data on VOCs and analyze their concentrations and reactivity.Additionally,the PMF(positive matrix factorization)method was utilized to identify the VOCs sources.Results indicated that the TVOCs(total VOCs)concentration was(96.7±63.4μg/m^3),with alkanes exhibiting the highest concentration of(36.1±26.4μg/m^3),followed by OVOCs(16.4±14.4μg/m^3).The key active components were alkenes and aromatics,among which xylene,propylene,toluene,propionaldehyde,acetaldehyde,ethylene,and styrene played crucial roles as reactive species.The sources derived from PMF analysis encompassed vehicle emissions,solvent and coating sources,combustion sources,industrial emissions sources,as well as plant sources,the contribution of which were 37.80%,27.93%,16.57%,15.24%,and 2.46%,respectively.Hence,reducing vehicular exhaust emissions and encouraging neighboring industries to adopt low-volatile organic solvents and coatings should be prioritized to mitigate VOCs levels.展开更多
Initial success has been achieved in Hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three decades.Volatile organic compounds(VOCs)are important for mitigating ...Initial success has been achieved in Hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three decades.Volatile organic compounds(VOCs)are important for mitigating ozone pollution as its major precursors.This study analyzed VOC characteristics of roadside,suburban,and rural sites in Hong Kong to investigate their compositions,concentrations,and source contributions.Herewe showthat the TVOC concentrations were 23.05±13.24,12.68±15.36,and 5.16±5.48 ppbv for roadside,suburban,and rural sites between May 2015 to June 2019,respectively.By using Positive Matrix Factorization(PMF)model,six sources were identified at the roadside site over five years:Liquefied petroleum gas(LPG)usage(33%–46%),gasoline evaporation(8%–31%),aged air mass(11%–28%),gasoline exhaust(5%–16%),diesel exhaust(2%–16%)and fuel filling(75–9%).Similarly,six sources were distinguished at the suburban site,including LPG usage(30%–33%),solvent usage(20%–26%),diesel exhaust(14%–26%),gasoline evaporation(8%–16%),aged air mass(4%–11%),and biogenic emissions(2%–5%).At the rural site,four sources were identified,including aged airmass(33%–51%),solvent usage(25%–30%),vehicular emissions(11%–28%),and biogenic emissions(6%–12%).The analysis further revealed that fuel filling and LPG usage were the primary contributors to OFP and OH reactivity at the roadside site,while solvent usage and biogenic emissions accounted for almost half of OFP and OH reactivity at the suburban and rural sites,respectively.These findings highlight the importance of identifying and characterizing VOC sources at different sites to help policymakers develop targeted measures for pollution mitigation in specific areas.展开更多
Furniture is identified as a vital volatile organic compound(VOC)emission source in the indoor environment.Leather has become the most common raw and auxiliary fabric material for upholstered furniture,particularly wi...Furniture is identified as a vital volatile organic compound(VOC)emission source in the indoor environment.Leather has become the most common raw and auxiliary fabric material for upholstered furniture,particularly with extensive consumption in sofas,due to its abundant resources and efficient functions.Despite being widely traded across the world,little research has been conducted on the VOCs released by leathermaterials and their health risk assessment in the indoor environment.Accordingly,this study investigated the VOC emissions of leather with different grades and the health risk of the inhalation exposure.Based on the ultra-fast gas phase electronic nose(EN)and GC-FID/Qtof,the substantial emissions of aliphatic aldehyde ketones(Aks),particularly hexanal,appear to be the cause of off-flavor in medium and low grade(MG and LG)sofa leathers.The health risk assessment indicated that leather materials barely pose non-carcinogenic and carcinogenic effects to residents.Given the abundance of VOC sources and the accumulation of health risks in the indoor environment,more stringent specifications concerning qualitative and quantitative content should be extended to provide VOC treatment basic for the manufacturing industry and obtain better indoor air quality.展开更多
Tomato is an important economic crop all over the world.Volatile flavors in tomato fruit are key factors influencing consumer liking and commercial quality.However,the regulatory mechanism controlling the volatile fla...Tomato is an important economic crop all over the world.Volatile flavors in tomato fruit are key factors influencing consumer liking and commercial quality.However,the regulatory mechanism controlling the volatile flavors of tomatoes is still not clear.Here,we integrated the metabolome and transcriptome of the volatile flavors in tomato fruit to explore the regulatory mechanism of volatile flavor formation,using wild and cultivated tomatoes with significant differences in flavors.A total of 35 volatile flavor compounds were identified,based on the solid phase microextraction-gas chromatography-mass spectrometry(SPME-GC-MS).The content of the volatiles,affecting fruit flavor,significantly increased in the transition from breaker to red ripe fruit stage.Moreover,the total content of the volatiles in wild tomatoes was much higher than that in the cultivated tomatoes.The content variations of all volatile flavors were clustered into 10 groups by hierarchical cluster and Pearson coefficient correlation(PCC)analysis.The fruit transcriptome was also patterned into 10 groups,with significant variations both from the mature green to breaker fruit stage and from the breaker to red ripe fruit stage.Combining the metabolome and the transcriptome of the same developmental stage of fruits by co-expression analysis,we found that the expression level of 1182 genes was highly correlated with the content of volatile flavor compounds,thereby constructing two regulatory pathways of important volatile flavors.One pathway is tetrahydrothiazolidine N-hydroxylase(SlTNH1)-dependent,which is regulated by two transcription factors(TFs)from the bHLH and AP2/ERF families,controlling the synthesis of 2-isobutylthiazole in amino acid metabolism.The other is lipoxygenase(Sl LOX)-dependent,which is regulated by one TF from the HD-Zip family,controlling the synthesis of hexanal and(Z)-2-heptenal in fatty acid metabolism.Dual-luciferase assay confirmed the binding of b HLH and AP2/ERF to their structural genes.The findings of this study provide new insights into volatile flavor formation in tomato fruit,which can be useful for tomato flavor improvement.展开更多
Ubiquitous contamination of the soil environment with volatile organic compounds(VOCs)has raised considerable concerns.However,there is still limited comprehensive surveying of soil VOCs on a national scale.Herein,65 ...Ubiquitous contamination of the soil environment with volatile organic compounds(VOCs)has raised considerable concerns.However,there is still limited comprehensive surveying of soil VOCs on a national scale.Herein,65 species of VOCswere simultaneously determined in surface soil samples collected from 63 chemical industrial parks(CIPs)across China.The results showed that the total VOC concentrations ranged from 7.15 to 1842 ng/g with a mean concentration of 326 ng/g(median:179 ng/g).Benzene homologs and halogenated hydrocarbons were identified as the dominant contaminant groups.Positive correlations between many VOC species indicated that these compounds probably originated from similar sources.Spatially,the hotspots of VOC pollution were located in eastern and southern China.Soils with higher clay content and a higher fraction of total organic carbon(TOC)content were significantly associated with higher soil VOC concentrations.Precipitation reduces the levels of highly water-soluble substances in surface soils.Both positive matrix factorization(PMF)and principal component analysis-multiple linear regression(PCA-MLR)identified a high proportion of industrial sources(PMF:59.2%and PCA-MLR:66.5%)and traffic emission sources(PMF:32.3%and PCA-MLR:33.5%).PMF,which had a higher R^(2) value(0.7892)than PCA-MLR(0.7683),was the preferred model for quantitative source analysis of soil VOCs.The health risk assessment indicated that the non-carcinogenic and carcinogenic risks of VOCs were at acceptable levels.Overall,this study provides valuable data on the occurrence of VOCs in soil from Chinese CIPs,which is essential for a comprehensive understanding of their environmental behavior.展开更多
Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in China.In vine tea processing,a large amount of broken tea is produced,which has low commercial value.Methods:This study investigat...Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in China.In vine tea processing,a large amount of broken tea is produced,which has low commercial value.Methods:This study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(URE),and ultrasonic assistance in boiling water extraction(UBE))on the yield,dihydromyricetin(DMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea extracts.Results:A notable influence of extraction temperature on the yield of vine tea extracts(P<0.05),with BE yielding the highest at 43.13±0.26%,higher than that of RE(34.29±0.81%).Ultrasound-assisted extraction significantly increased the DMY content of the extracts(P<0.05),whereas DMY content in the RE extracts was 59.94±1.70%,that of URE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid content.Gas chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted extraction.Specifically,69 and 68 volatile compounds were found in URE and UBE extracts,which were higher than the number found in RE and BE extracts.In vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest DPPH scavenging rate,URE leading in ABTS•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant activity.Conclusion:The findings suggest that extraction methods significantly influence the chemical composition and antioxidant properties of vine tea extracts.Ultrasonic-assisted extraction proved instrumental in elevating the DMY content in vine tea extracts,thereby enriching its flavor profile while maintaining its antioxidant properties.展开更多
Halide perovskites is a recently emerged platform for the creation of efficient memristors.In turn,single-crystal inorganic perovskite would be new low-cost and flexible memory devices because of their excellent resis...Halide perovskites is a recently emerged platform for the creation of efficient memristors.In turn,single-crystal inorganic perovskite would be new low-cost and flexible memory devices because of their excellent resistive switching(RS)properties,without risk of chemical and mechanical stress-generated degradation,compared with the operational instability of general thin-film perovskite memristors.Moreover,miniaturization of perovskite memristors would be useful for creating high-density memory devices.Here we demonstrate the smallest CsPbBr3 perovskite nanomemristor with volatile unipolar RS characteristics which depends on the size of a single-crystal as a resistive layer due to its overall structural stability and low sensitivity to atmosphere conditions that helps to keep the stable RS switching over 1500 times with the lowest consumption power of 70 nW.To better understand the RS mechanism,we provide a comprehensive simulation of the evolution of mixed ionic-electronic charge carriers under current-voltage(I-V)tests using a one-dimensional drift-diffusion model.Because of the nonreactive nature of the contacts,the main mechanism of resistive state switching is potential barrier modulation of the Schottky contacts through the accumulation of migrating ions at the interfaces.Our findings pave the way for ultracompact memristors as well as shed light on RS mechanism in non-filamentary perovskitebased memory devices.展开更多
The anaerobic acid production experiments were conducted with the pretreated kitchen waste under pH adjustment.The results showed that pH 8 was considered to be the most suitable condition for acid production,especial...The anaerobic acid production experiments were conducted with the pretreated kitchen waste under pH adjustment.The results showed that pH 8 was considered to be the most suitable condition for acid production,especially for the formation of acetic acid and propionic acid.The average value of total volatile fatty acid at pH 8 was 8814 mg COD/L,1.5 times of that under blank condition.The average yield of acetic acid and propionic acid was 3302 mg COD/L and 2891 mg COD/L,respectively.The activities of key functional enzymes such as phosphotransacetylase,acetokinase,oxaloacetate transcarboxylase and succinylcoA transferase were all enhanced.To further explore the regulatory mechanisms within the system,the distribution of microorganisms at different levels in the fermentation system was obtained by microbial sequencing,results indicating that the relative abundances of Clostridiales,Bacteroidales,Chloroflexi,Clostridium,Bacteroidetes and Propionibacteriales,which were great contributors for the hydrolysis and acidification,increased rapidly at pH 8 compared with the blank group.Besides,the proportion of genes encoding key enzymes was generally increased,which further verified the mechanism of hydrolytic acidification and acetic acid production of organic matter under pH regulation.展开更多
Volatile organic chemicals(VOC)have been identified as hazardous pollutants impairing human health.While whether the VOC exposure was associated with hyperuricemia is yet clarified.All the data was acquired from 6 sur...Volatile organic chemicals(VOC)have been identified as hazardous pollutants impairing human health.While whether the VOC exposure was associated with hyperuricemia is yet clarified.All the data was acquired from 6 survey cycles of the National Health and Nutrition Examination Survey(NHANES)program(2005–2006,2011–2012,2013–2014,2015–2016,2017–2018,2017–2020).Hyperuricemia was defined as a serum uric acid(SUA)concentration exceeding 7 mg/mL in men or 6 mg/mL in women.Three quantile logistic regression modelswith varied covariateswere developed to analyze the correlation between hyperuricemia and volatile organic chemical metabolites(VOCs)in urine,and three quantile linear regression models were used for examining the correlation between VOCs and SUA.N-acetyl-S-(2-carboxyethyl)-l-cysteine(CEMA),N-acetyl-S-(3,4-dihydroxybutyl)-l-cysteine(DHBM),and phenylglyoxylic acid(PHGA)were identified to associated positively with increased hyperuricemia risk and uric acid level.Meanwhile,the weighted quantile sum(WQS)model suggested a positive association between VOCs exposure and hyperuricemia.These data indicate that VOC exposure potentially increases hyperuricemia risk,necessitating policies to mitigate VOC exposure.展开更多
Serious fine particulate matter(PM_(2.5))pollution and rapidly increasing of ground-level ozone(O_(3))concentrations are concern issues in China.To achieve the comprehensive control of PM_(2.5)-O_(3) composite air pol...Serious fine particulate matter(PM_(2.5))pollution and rapidly increasing of ground-level ozone(O_(3))concentrations are concern issues in China.To achieve the comprehensive control of PM_(2.5)-O_(3) composite air pollution,exploring the common sources of PM_(2.5) and VOCs is essential.However,previous researches most carried out either PM_(2.5) or VOCs source appointment.In this study,we applied the ensemble source apportionment method to explore the impacts of common sources on PM_(2.5)-VOCs.Subsequently,we obtained the ensemble source impacts on O_(3) combining the extracted VOCs source profile and ozone formation potential.We found that the focus of environmentalmanagement and source control should be varied accordingly for different pollutants.Vehicle emission was the largest contributor(41%)to PM_(2.5)-VOCs,while industrial emission was the main common source(51%)to O_(3).The result showed that the O_(3) production rate is not only related to the VOCs emission,but also to the reactivity of VOCs.In addition,sensitivity tests revealed that temperature was the main factor affecting O_(3) formation.The study provides a framework to explore the common sources impact on PM_(2.5) and VOCs,which is benefit to address both PM_(2.5) and O_(3) mitigations.展开更多
The BZ oilfield in the Bohai Sea is a rare,highly volatile reservoir with fractures in the metamorphic rocks of buried hills.Clarifying the mechanism of gas injection for improving oil recovery and determining the opt...The BZ oilfield in the Bohai Sea is a rare,highly volatile reservoir with fractures in the metamorphic rocks of buried hills.Clarifying the mechanism of gas injection for improving oil recovery and determining the optimal way to deploy injection-production well networks are critical issues that must be urgently addressed for efficient oilfield development.Experimental research on the mixed-phase displacement mechanism through gas injection into indoor formation fluids was conducted to guide the efficient development of gas injection in oil fields.We established a model of dual-medium reservoir composition and researched the deployment strategy for a three-dimensional well network for gas injection development.The coupling relationship between key influencing factors of the well network and fracture development was also quantitatively analyzed.The results show that the solubility of the associated gas and strong volatile oil system injected into the BZ oilfield is high.This high solubility demonstrates a mixed-phase displacement mechanism involving intermediate hydrocarbons,dissolution and condensation of medium components,and coexistence of extraction processes.Injecting gas and crude oil can achieve a favorable mixing effect when the local formation pressure is greater than 35.79 MPa.Associated gas reinjection is recommended to supplement energy for developing the highly volatile oil reservoirs in the fractured buried hills of the BZ oilfield.This recommendation involves fully utilizing the structural position and gravity-assisted oil displacement mechanism to deploy an injection-production well network.Gas injection points should be constructed at the top of high areas,and oil production points should be placed at the middle and lower parts of low areas.This approach forms a spatial threedimensional well network.By adopting high inclination well development,the oil production well forms a 45°angle with the fracture direction,which increases the drainage area and enhances single-well production capacity.The optimal injection-production well spacing along the fracture direction is approximately 1000 m,while the reasonable well spacing in the vertical fracture direction is approximately 800 m.The research results were applied to the development practice of the buried hills in the BZ oilfield,which achieved favorable development results.These outcomes provide a valuable reference for the formulation of development plans and efficient gas injection development in similar oil and gas fields in buried hills.展开更多
Anaerobic fermentation is an efficient method to extract phosphorus from excess sludge,thereby facilitating its recovery and mitigating the phosphorus resource shortage.However,the prevalent metal-bound phosphorus spe...Anaerobic fermentation is an efficient method to extract phosphorus from excess sludge,thereby facilitating its recovery and mitigating the phosphorus resource shortage.However,the prevalent metal-bound phosphorus species within sludge was difficult to release into the fermentation liquor.To address this,this study evaluated the enhanced phosphorus release performance from sludge containing iron-phosphorus compounds(Fe-P)via co-fermenting it with agriculture wastes.Specifically,protein-rich feather(Feather Group)and polysaccharide-rich tea residue(Tea Group)was respectively dosed into batch-scale fermentation jar.Results showed that the Feather Group exhibited significantly higher levels of released soluble phosphorus(2.1 folds)and volatile fatty acids(41.4 folds)compared to the Control Group,with concentrations reaching up to 280 mg/L and 9366 mg chemical oxygen demand/L,respectively.The activities ofα-glucosidase,neutral protease and acetate kinase in the Feather group were increased by 11.1%,92.3%and 37.6%,respectively,compared with the Control group.Methanogen abundance decreased while hydrolytic acid-producing bacteria and iron-reducing bacteria increased significantly after supplying agricultural wastes.Metagenomic analysis demonstrated a significant increase in genes related to acetic acid synthesis.Mechanism elucidation suggested that increased iron-reducing bacteria abundance promoted Fe3+reduction into Fe2+,thus enhancing phosphorus release from Fe-P compounds.This work may provide valuable information for developing effective strategy to extract phosphorus resource from complex environmental wastes.展开更多
Wide bandgap semiconductors are typically activated under ultraviolet(UV)light irradiation for volatile organic compounds(VOCs)degradation.However,our previous study discovered that certain VOCs can interact with some...Wide bandgap semiconductors are typically activated under ultraviolet(UV)light irradiation for volatile organic compounds(VOCs)degradation.However,our previous study discovered that certain VOCs can interact with some wide bandgap semiconductors,formatting an intermediate bandgap between the VOCs and the conduction band of wide bandgap semiconductor,thus inducing visible light activation of the system,and photo-generated electrons are excited by visible light and transferred from the VOCs to the conduction band of semiconductor.In this work,BaTiO_(3),traditionally is not active under visible light irradiation,however showed degradation rates of 100%and 20%for styrene and toluene under visible light,respectively.Density functional theory(DFT)calculations indicate that the adsorption of styrene or toluene on the BaTiO_(3)surface reduces its bandgap from 2.93 eV to 1.36 eV and 2.26 eV,respectively.The intermediate bandgap in this system is primarily formed by the valence band of BaTiO_(3)and the VOCs,and indicating that photo-generated electrons directly transfer from BaTiO_(3)to the VOCs under visible light,inducing degradation reactions of VOCs,i.e.,this work discovered a new transfer pathway of photo-electrons direct from the valence band of BaTiO_(3)to VOCs,while photo-electrons are from VOCs to the conductive band of wide-bandgap semiconductors in our previous work.展开更多
The third member of Shahejie Formation(also referred to as Sha 3 Member)in Dongpu Depression,China,a volatile,low-permeability oil reservoir with complex fluid compositions,is subjected to high temperature and high pr...The third member of Shahejie Formation(also referred to as Sha 3 Member)in Dongpu Depression,China,a volatile,low-permeability oil reservoir with complex fluid compositions,is subjected to high temperature and high pressure(HPHT),which poses significant challenges to conventional water injection.To elucidate flow mechanisms and optimize development strategies,this study integrates constant-rate mercury injection(CRMI),nuclear magnetic resonance(NMR),and HPHT three-phase oil/gas/water relative permeability experiments to analyze pore-throat structures,movable fluid characteristics,and relative permeability.The CRMI results indicate that the reservoir exhibits low porosity and low permeability,with dominant throat radius ranging from 0.6 to 5.0μm,and mean pore-throat radius ratio ranging from 40.303 to 278.320,demonstrating significant microscopic heterogeneity.The NMR results reveal that water-alternating-gas(WAG)injection enhances oil recovery by 16.28%(Sample W1)and 13.52%(Sample W2)compared to conventional water injection,primarily due to the gas phase's low viscosity and high mobility,enabling access to micropores unreachable by water phases.The HPHT three-phase relative permeability tests demonstrate positive correlations between saturation and relative permeability,with oil permeability significantly influenced by three-phase saturation and rock wettability.These findings establish a microscopic seepage model for optimizing enhanced oil recovery(EOR)strategies in volatile reservoirs.展开更多
Angelica L.has attracted global interest for its traditional medicinal uses and commercial values.However,few studies have focused on the metabolomic differences among the Angelica species.In this study,widely targete...Angelica L.has attracted global interest for its traditional medicinal uses and commercial values.However,few studies have focused on the metabolomic differences among the Angelica species.In this study,widely targeted metabolomics based on gas chromatography-tandem mass spectrometry was employed to analyze the metabolomes of four Angelica species(Angelicasinensis(Oliv.)Diels(A.sinensis),Angelica biserrata(R.H.Shan &Yuan)C.Q.Yuan & R.H.Shan(A.biserrata),Angelica dahurica(Hoffm.)Benth.& Hook.f.ex Franch.& Sav.(A.dahurica)and Angelica keiskei Koidz.(A.keiskei)).A total of 698 volatile metabolites were identified and classified into fifteen different categories.The metabo-lomic analysis indicated that 7-hydroxycoumarin and Z-ligustilide accumulated at significantly higher levels in A.sinensis,whereas bornyl acetate showed the opposite pattern.Furthermore,a high correspondence between the dendrogram of metabolite contents and phylogenetic positions of the four species.This study provides a comprehensive biochemical map for the exploitation,application and development of the Angelica species as medicinal plants or health-related dietary supplements.展开更多
Microbial growth causes lamb spoilage.This study explored the spoilage ability of Latilactobacillus sakei,Serratia proteamaculans and Hafnia proteus in vacuum-packed raw lamb,including growth ability,degradation of pr...Microbial growth causes lamb spoilage.This study explored the spoilage ability of Latilactobacillus sakei,Serratia proteamaculans and Hafnia proteus in vacuum-packed raw lamb,including growth ability,degradation of protein and lipid,and change of volatile organic compounds(VOCs)profile,meanwhile screened the key VOCs produced by the targeted strains with meat background excluding,finally confirmed the volatile spoilage marker of vacuum-packaged lamb by comparing with our previous work.The results showed that L.sakei,S.proteamaculans and H.proteus had excellent growth ability.L.sakei inoculated group significantly reduced the pH value,showed higher trichloroacetic acid-soluble peptides content,and excellently degraded sarcoplasmic and myofibrillar proteins.About free amino acids,L.sakei significantly degraded serine,arginine and aspartic acid,while S.proteamaculans and H.proteus significantly degraded serine and lysine.In addition,L.sakei had the strongest effect on promoting free fatty acid production,followed by S.proteamaculans and finally H.proteus.Evaluating from various indicators,the co-culture of the three strains did not have any effect.The key volatiles produced by L.sakei were 1-hexanol,acetic acid and hexanoic acid,S.proteamaculans produced 1-hexanol and acetoin,and H.proteus produced 1-hexanol,acetic acid and acetoin.In the end,1-hexanol,hexanoic acid and acetoin were proven to be spoilage markers for vacuum-packaged and chilled lamb.This study can provide fundamental information for inhibiting and rapid identification of spoilage in vacuum-packaged lamb.展开更多
Existing evidence has demonstrated the association between exposure to volatile organic compounds(VOCs)and osteoporosis(OP)risk,but the underlying mechanistic framework remains unclear.This study aimed to explore pote...Existing evidence has demonstrated the association between exposure to volatile organic compounds(VOCs)and osteoporosis(OP)risk,but the underlying mechanistic framework remains unclear.This study aimed to explore potential pathways using adverse outcome pathway(AOP)analysis,and evidence this association in middle-to-old-aged American adults using the updated National Health and Nutrition Examination Survey data.Multivariable-adjusted general linear and weighted quantile sum models were employed to analyze associations of VOC metabolites(VOCMs),representing internal VOCs exposure levels,with OP-related phenotypes.An AOP framework based on network analysis was developed by extracting target genes and phenotypes.Among 3555 American adults aged≥40 years(539 OP participants),we found that increasing urinary 3-and 4-methylhippuric acid,N-acetyl-S-(n-propyl)-l-cysteine(BPMA),and N-acetyl-S-(3-hydroxypropyl)-l-cysteine were associated with elevated OP odds with odds ratios(ORs)(95%confidence intervals,95%CIs)being 1.254(1.016 to 1.548),1.182(1.014 to 1.377),and 1.244(1.029 to 1.505),respectively,per standard deviation.Urinary BPMA and N-acetyl-S-(2-cyanoethyl)-l-cysteine were inversely associated with lumbar spine bone mineral density(BMD),while urinary N-acetyl-S-(2-hydroxypropyl)-l-cysteine was positively associated with hip BMD.Additionally,OP odds increased by 46.0%(95%CI:3.9%to 105.1%)per quartile increment in the VOC mixture.AOP analysis identified 53 target genes and 9 target phenotypes,and 5 of 9 target phenotypes were oxidative stress(OS)-related.Literature and the“AOP 482”framework implied the core role of OS in the VOC exposure and prevalent OP association,with the interleukin-6 as themolecular initiating event.Our findings provided a theoretical basis for further investigation.展开更多
基金supported by the R&D Projects in Key Areas of Guangdong Province(2023B0202080003)the National Natural Science Foundation of China(32472272,32302135,32072291)+1 种基金“Pioneer”and“Leading Goose”R&D Program of Zhejiang(2023C02006)Youth S&T Talent Support Programme of Guangdong Provincial Association for Science and Technology(SKXRC202401)。
文摘Edible oils derived from aquatic products are rich in lipids beneficial to human health.However,the volatile flavor characteristics of flesh oil and liver oil from Doederleinia berycoides remain unclear.In this study,flesh oil and liver oil were extracted from Doederleinia berycoides,revealing different fatty acid compositions and contents.Lipidomics analysis identified a total of 124 differential lipids between the flesh oil and liver oil,including 42 glycerophospholipids(GPs),33 glycerolipids(GLs),23 free fatty acids(FAs),13 sphingolipids(SPs),10 sterols(STs),and 3 prenol lipids(PRs).Analysis using HS-GC-IMS identified 12 key volatile compounds that significantly contributed to the distinct volatile flavors of the flesh and liver oils.The volatile flavors originated from these volatile compounds,which had different Relative Odor Activity Values(ROAVs).Further results from HSSPME-GC-MS showed that the volatile flavors of the flesh oil and liver oil were respectively attributed to 64 and 35 volatile compounds,each with unique key volatile compounds exhibiting different ROAVs.There were significant positive or negative correlations between 18 key differential lipids and 24 volatile compounds in both flesh oil and liver oil.Therefore,the complex lipid profiles are responsible for the unique volatile flavors of flesh oil and liver oil,and the differential lipids play a central role in their volatile flavor formation.These findings provide a foundation for understanding the volatile flavor differences in fish oils and hold promise for further exploration of the molecular mechanisms underlying oil volatile flavors.
基金supported by the Shanghai 3-year Public Health Action Plan(grant number:GWVI-11.1-39).
文摘Cyclic volatile methyl siloxanes(cVMSs)are widely used in industrial and consumer products because of their thermal stability,low reactivity,and reduced surface tension[1].Their extensive use has resulted in environmental pollution globally.Recognized as very persistent and very bioaccumulative(vPvB),compounds such as octamethylcyclotetrasiloxane(D4),decamethylcyclopentasiloxane(D5),and dodecamethylcyclohexasiloxane(D6)are regulated in the European Union[2]and are monitored worldwide.
基金supported by the National Natural Science Foundation of China (NSFC)Projects (Nos.42205105,42121004,and 42077190)the Science and Technology Project of Shaoguan (No.210811164532141)+3 种基金the National Key R&D Program of China (2022YFC3700604)the Science and Technology Program of Guangzhou City (No.202201010400)the Fundamental Research Funds for the Central Universities (No.21622319)the Research Center of Low Carbon Economy for Guangzhou Region (No.22JNZS50).
文摘Emission characteristics of biogenic volatile organic compounds(BVOCs)from dominant tree species in the subtropical pristine forests of China are extremely limited.Here we conducted in situ field measurements of BVOCs emissions from representative mature evergreen trees by using dynamic branch enclosures at four altitude gradients(600-1690ma.s.l.)in the Nanling Mountains of southern China.Composition characteristics as well as seasonal and altitudinal variations were analyzed.Standardized emission rates and canopyscale emission factors were then calculated.Results showed that BVOCs emission intensities in the wet season were generally higher than those in the dry season.Monoterpenes were the dominant BVOCs emitted from most broad-leaved trees,accounting for over 70%of the total.Schima superba,Yushania basihirsuta and Altingia chinensis had relatively high emission intensities and secondary pollutant formation potentials.The localized emission factors of isoprene were comparable to the defaults in the Model of Emissions of Gases and Aerosols fromNature(MEGAN),while emission factors of monoterpenes and sesquiterpenes were 2 to 58 times of those in the model.Our results can be used to update the current BVOCs emission inventory in MEGAN,thereby reducing the uncertainties of BVOCs emission estimations in forested regions of southern China.
基金supported by the Natural Science Foundation of Hebei Province(Nos.D2019106042,D2020304038,and D2021106002)the National Natural Science Foundation of China(No.22276099)+1 种基金the State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex(No.2021080544)the Environmental Monitoring Research Foundation of Jiangsu Province(No.2211).
文摘VOCs(Volatile organic compounds)exert a vital role in ozone and secondary organic aerosol production,necessitating investigations into their concentration,chemical characteristics,and source apportionment for the effective implementation of measures aimed at preventing and controlling atmospheric pollution.FromJuly to October 2020,onlinemonitoringwas conducted in the main urban area of Shijiazhuang to collect data on VOCs and analyze their concentrations and reactivity.Additionally,the PMF(positive matrix factorization)method was utilized to identify the VOCs sources.Results indicated that the TVOCs(total VOCs)concentration was(96.7±63.4μg/m^3),with alkanes exhibiting the highest concentration of(36.1±26.4μg/m^3),followed by OVOCs(16.4±14.4μg/m^3).The key active components were alkenes and aromatics,among which xylene,propylene,toluene,propionaldehyde,acetaldehyde,ethylene,and styrene played crucial roles as reactive species.The sources derived from PMF analysis encompassed vehicle emissions,solvent and coating sources,combustion sources,industrial emissions sources,as well as plant sources,the contribution of which were 37.80%,27.93%,16.57%,15.24%,and 2.46%,respectively.Hence,reducing vehicular exhaust emissions and encouraging neighboring industries to adopt low-volatile organic solvents and coatings should be prioritized to mitigate VOCs levels.
基金supported by Hong Kong Environment Protection Department(Quotation Ref.18-06532)Hong Kong Innovation and Technology Fund(ITS/193/20FP)Hong Kong Research Grants Council(No.26304921).
文摘Initial success has been achieved in Hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three decades.Volatile organic compounds(VOCs)are important for mitigating ozone pollution as its major precursors.This study analyzed VOC characteristics of roadside,suburban,and rural sites in Hong Kong to investigate their compositions,concentrations,and source contributions.Herewe showthat the TVOC concentrations were 23.05±13.24,12.68±15.36,and 5.16±5.48 ppbv for roadside,suburban,and rural sites between May 2015 to June 2019,respectively.By using Positive Matrix Factorization(PMF)model,six sources were identified at the roadside site over five years:Liquefied petroleum gas(LPG)usage(33%–46%),gasoline evaporation(8%–31%),aged air mass(11%–28%),gasoline exhaust(5%–16%),diesel exhaust(2%–16%)and fuel filling(75–9%).Similarly,six sources were distinguished at the suburban site,including LPG usage(30%–33%),solvent usage(20%–26%),diesel exhaust(14%–26%),gasoline evaporation(8%–16%),aged air mass(4%–11%),and biogenic emissions(2%–5%).At the rural site,four sources were identified,including aged airmass(33%–51%),solvent usage(25%–30%),vehicular emissions(11%–28%),and biogenic emissions(6%–12%).The analysis further revealed that fuel filling and LPG usage were the primary contributors to OFP and OH reactivity at the roadside site,while solvent usage and biogenic emissions accounted for almost half of OFP and OH reactivity at the suburban and rural sites,respectively.These findings highlight the importance of identifying and characterizing VOC sources at different sites to help policymakers develop targeted measures for pollution mitigation in specific areas.
基金supported by the National Key Research and Development Program of China (No.2019YFC1904501).
文摘Furniture is identified as a vital volatile organic compound(VOC)emission source in the indoor environment.Leather has become the most common raw and auxiliary fabric material for upholstered furniture,particularly with extensive consumption in sofas,due to its abundant resources and efficient functions.Despite being widely traded across the world,little research has been conducted on the VOCs released by leathermaterials and their health risk assessment in the indoor environment.Accordingly,this study investigated the VOC emissions of leather with different grades and the health risk of the inhalation exposure.Based on the ultra-fast gas phase electronic nose(EN)and GC-FID/Qtof,the substantial emissions of aliphatic aldehyde ketones(Aks),particularly hexanal,appear to be the cause of off-flavor in medium and low grade(MG and LG)sofa leathers.The health risk assessment indicated that leather materials barely pose non-carcinogenic and carcinogenic effects to residents.Given the abundance of VOC sources and the accumulation of health risks in the indoor environment,more stringent specifications concerning qualitative and quantitative content should be extended to provide VOC treatment basic for the manufacturing industry and obtain better indoor air quality.
基金supported by the National Natural Science Foundation of China(Grant Nos.32120103010,32002050)Beijing Joint Research Program for Germplasm Innovation and New Variety Breeding(Grant No.G20220628003-03)the Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences。
文摘Tomato is an important economic crop all over the world.Volatile flavors in tomato fruit are key factors influencing consumer liking and commercial quality.However,the regulatory mechanism controlling the volatile flavors of tomatoes is still not clear.Here,we integrated the metabolome and transcriptome of the volatile flavors in tomato fruit to explore the regulatory mechanism of volatile flavor formation,using wild and cultivated tomatoes with significant differences in flavors.A total of 35 volatile flavor compounds were identified,based on the solid phase microextraction-gas chromatography-mass spectrometry(SPME-GC-MS).The content of the volatiles,affecting fruit flavor,significantly increased in the transition from breaker to red ripe fruit stage.Moreover,the total content of the volatiles in wild tomatoes was much higher than that in the cultivated tomatoes.The content variations of all volatile flavors were clustered into 10 groups by hierarchical cluster and Pearson coefficient correlation(PCC)analysis.The fruit transcriptome was also patterned into 10 groups,with significant variations both from the mature green to breaker fruit stage and from the breaker to red ripe fruit stage.Combining the metabolome and the transcriptome of the same developmental stage of fruits by co-expression analysis,we found that the expression level of 1182 genes was highly correlated with the content of volatile flavor compounds,thereby constructing two regulatory pathways of important volatile flavors.One pathway is tetrahydrothiazolidine N-hydroxylase(SlTNH1)-dependent,which is regulated by two transcription factors(TFs)from the bHLH and AP2/ERF families,controlling the synthesis of 2-isobutylthiazole in amino acid metabolism.The other is lipoxygenase(Sl LOX)-dependent,which is regulated by one TF from the HD-Zip family,controlling the synthesis of hexanal and(Z)-2-heptenal in fatty acid metabolism.Dual-luciferase assay confirmed the binding of b HLH and AP2/ERF to their structural genes.The findings of this study provide new insights into volatile flavor formation in tomato fruit,which can be useful for tomato flavor improvement.
基金supported by the Medical and Health Projects in Zhejiang Province(No.2022PY049)the Basic Scientific Research Project of Hangzhou Medical College(No.YS2021006)Key Discipline of Zhejiang Province in Public Health and Preventive Medicine(First Class,Category A),Hangzhou Medical College.
文摘Ubiquitous contamination of the soil environment with volatile organic compounds(VOCs)has raised considerable concerns.However,there is still limited comprehensive surveying of soil VOCs on a national scale.Herein,65 species of VOCswere simultaneously determined in surface soil samples collected from 63 chemical industrial parks(CIPs)across China.The results showed that the total VOC concentrations ranged from 7.15 to 1842 ng/g with a mean concentration of 326 ng/g(median:179 ng/g).Benzene homologs and halogenated hydrocarbons were identified as the dominant contaminant groups.Positive correlations between many VOC species indicated that these compounds probably originated from similar sources.Spatially,the hotspots of VOC pollution were located in eastern and southern China.Soils with higher clay content and a higher fraction of total organic carbon(TOC)content were significantly associated with higher soil VOC concentrations.Precipitation reduces the levels of highly water-soluble substances in surface soils.Both positive matrix factorization(PMF)and principal component analysis-multiple linear regression(PCA-MLR)identified a high proportion of industrial sources(PMF:59.2%and PCA-MLR:66.5%)and traffic emission sources(PMF:32.3%and PCA-MLR:33.5%).PMF,which had a higher R^(2) value(0.7892)than PCA-MLR(0.7683),was the preferred model for quantitative source analysis of soil VOCs.The health risk assessment indicated that the non-carcinogenic and carcinogenic risks of VOCs were at acceptable levels.Overall,this study provides valuable data on the occurrence of VOCs in soil from Chinese CIPs,which is essential for a comprehensive understanding of their environmental behavior.
基金supported by the Key Research and Development Program of Hunan Province of China(No.2022NK2036)Xiangxi Prefecture Science and Technology Plan Project"School-Local Integration"Special Project(No.2022001)the scientific research project of Hunan Provincial Department of Education(No.22B0520).
文摘Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in China.In vine tea processing,a large amount of broken tea is produced,which has low commercial value.Methods:This study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(URE),and ultrasonic assistance in boiling water extraction(UBE))on the yield,dihydromyricetin(DMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea extracts.Results:A notable influence of extraction temperature on the yield of vine tea extracts(P<0.05),with BE yielding the highest at 43.13±0.26%,higher than that of RE(34.29±0.81%).Ultrasound-assisted extraction significantly increased the DMY content of the extracts(P<0.05),whereas DMY content in the RE extracts was 59.94±1.70%,that of URE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid content.Gas chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted extraction.Specifically,69 and 68 volatile compounds were found in URE and UBE extracts,which were higher than the number found in RE and BE extracts.In vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest DPPH scavenging rate,URE leading in ABTS•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant activity.Conclusion:The findings suggest that extraction methods significantly influence the chemical composition and antioxidant properties of vine tea extracts.Ultrasonic-assisted extraction proved instrumental in elevating the DMY content in vine tea extracts,thereby enriching its flavor profile while maintaining its antioxidant properties.
基金supported by the Russian Science Foundation(project number 24-62-00022)for data analysis and by Priority 2030 Federal Academic Leadership Program for samples synthesis.
文摘Halide perovskites is a recently emerged platform for the creation of efficient memristors.In turn,single-crystal inorganic perovskite would be new low-cost and flexible memory devices because of their excellent resistive switching(RS)properties,without risk of chemical and mechanical stress-generated degradation,compared with the operational instability of general thin-film perovskite memristors.Moreover,miniaturization of perovskite memristors would be useful for creating high-density memory devices.Here we demonstrate the smallest CsPbBr3 perovskite nanomemristor with volatile unipolar RS characteristics which depends on the size of a single-crystal as a resistive layer due to its overall structural stability and low sensitivity to atmosphere conditions that helps to keep the stable RS switching over 1500 times with the lowest consumption power of 70 nW.To better understand the RS mechanism,we provide a comprehensive simulation of the evolution of mixed ionic-electronic charge carriers under current-voltage(I-V)tests using a one-dimensional drift-diffusion model.Because of the nonreactive nature of the contacts,the main mechanism of resistive state switching is potential barrier modulation of the Schottky contacts through the accumulation of migrating ions at the interfaces.Our findings pave the way for ultracompact memristors as well as shed light on RS mechanism in non-filamentary perovskitebased memory devices.
基金supported by the National Key Research and Development Program of China(No.2019YFC1906304).
文摘The anaerobic acid production experiments were conducted with the pretreated kitchen waste under pH adjustment.The results showed that pH 8 was considered to be the most suitable condition for acid production,especially for the formation of acetic acid and propionic acid.The average value of total volatile fatty acid at pH 8 was 8814 mg COD/L,1.5 times of that under blank condition.The average yield of acetic acid and propionic acid was 3302 mg COD/L and 2891 mg COD/L,respectively.The activities of key functional enzymes such as phosphotransacetylase,acetokinase,oxaloacetate transcarboxylase and succinylcoA transferase were all enhanced.To further explore the regulatory mechanisms within the system,the distribution of microorganisms at different levels in the fermentation system was obtained by microbial sequencing,results indicating that the relative abundances of Clostridiales,Bacteroidales,Chloroflexi,Clostridium,Bacteroidetes and Propionibacteriales,which were great contributors for the hydrolysis and acidification,increased rapidly at pH 8 compared with the blank group.Besides,the proportion of genes encoding key enzymes was generally increased,which further verified the mechanism of hydrolytic acidification and acetic acid production of organic matter under pH regulation.
基金supported by the National Natural Science Foundation of China(No.82360437)the Key Research and Development Program of Hunan Province(No.2021SK2012).
文摘Volatile organic chemicals(VOC)have been identified as hazardous pollutants impairing human health.While whether the VOC exposure was associated with hyperuricemia is yet clarified.All the data was acquired from 6 survey cycles of the National Health and Nutrition Examination Survey(NHANES)program(2005–2006,2011–2012,2013–2014,2015–2016,2017–2018,2017–2020).Hyperuricemia was defined as a serum uric acid(SUA)concentration exceeding 7 mg/mL in men or 6 mg/mL in women.Three quantile logistic regression modelswith varied covariateswere developed to analyze the correlation between hyperuricemia and volatile organic chemical metabolites(VOCs)in urine,and three quantile linear regression models were used for examining the correlation between VOCs and SUA.N-acetyl-S-(2-carboxyethyl)-l-cysteine(CEMA),N-acetyl-S-(3,4-dihydroxybutyl)-l-cysteine(DHBM),and phenylglyoxylic acid(PHGA)were identified to associated positively with increased hyperuricemia risk and uric acid level.Meanwhile,the weighted quantile sum(WQS)model suggested a positive association between VOCs exposure and hyperuricemia.These data indicate that VOC exposure potentially increases hyperuricemia risk,necessitating policies to mitigate VOC exposure.
基金supported by the National Key Research and Development Program of China(Nos.2023YFC3709500,2023YFC3709502 and 2022YFC3703400)the National Natural Science Foundation of China(No.42077191)+1 种基金the Fundamental Research Funds for the Central Universities(No.63233054)Tianjin Science and Technology Plan Project(No.18PTZWHZ00120).
文摘Serious fine particulate matter(PM_(2.5))pollution and rapidly increasing of ground-level ozone(O_(3))concentrations are concern issues in China.To achieve the comprehensive control of PM_(2.5)-O_(3) composite air pollution,exploring the common sources of PM_(2.5) and VOCs is essential.However,previous researches most carried out either PM_(2.5) or VOCs source appointment.In this study,we applied the ensemble source apportionment method to explore the impacts of common sources on PM_(2.5)-VOCs.Subsequently,we obtained the ensemble source impacts on O_(3) combining the extracted VOCs source profile and ozone formation potential.We found that the focus of environmentalmanagement and source control should be varied accordingly for different pollutants.Vehicle emission was the largest contributor(41%)to PM_(2.5)-VOCs,while industrial emission was the main common source(51%)to O_(3).The result showed that the O_(3) production rate is not only related to the VOCs emission,but also to the reactivity of VOCs.In addition,sensitivity tests revealed that temperature was the main factor affecting O_(3) formation.The study provides a framework to explore the common sources impact on PM_(2.5) and VOCs,which is benefit to address both PM_(2.5) and O_(3) mitigations.
文摘The BZ oilfield in the Bohai Sea is a rare,highly volatile reservoir with fractures in the metamorphic rocks of buried hills.Clarifying the mechanism of gas injection for improving oil recovery and determining the optimal way to deploy injection-production well networks are critical issues that must be urgently addressed for efficient oilfield development.Experimental research on the mixed-phase displacement mechanism through gas injection into indoor formation fluids was conducted to guide the efficient development of gas injection in oil fields.We established a model of dual-medium reservoir composition and researched the deployment strategy for a three-dimensional well network for gas injection development.The coupling relationship between key influencing factors of the well network and fracture development was also quantitatively analyzed.The results show that the solubility of the associated gas and strong volatile oil system injected into the BZ oilfield is high.This high solubility demonstrates a mixed-phase displacement mechanism involving intermediate hydrocarbons,dissolution and condensation of medium components,and coexistence of extraction processes.Injecting gas and crude oil can achieve a favorable mixing effect when the local formation pressure is greater than 35.79 MPa.Associated gas reinjection is recommended to supplement energy for developing the highly volatile oil reservoirs in the fractured buried hills of the BZ oilfield.This recommendation involves fully utilizing the structural position and gravity-assisted oil displacement mechanism to deploy an injection-production well network.Gas injection points should be constructed at the top of high areas,and oil production points should be placed at the middle and lower parts of low areas.This approach forms a spatial threedimensional well network.By adopting high inclination well development,the oil production well forms a 45°angle with the fracture direction,which increases the drainage area and enhances single-well production capacity.The optimal injection-production well spacing along the fracture direction is approximately 1000 m,while the reasonable well spacing in the vertical fracture direction is approximately 800 m.The research results were applied to the development practice of the buried hills in the BZ oilfield,which achieved favorable development results.These outcomes provide a valuable reference for the formulation of development plans and efficient gas injection development in similar oil and gas fields in buried hills.
基金supported by the“Pioneer”and“Leading Goose”R&D Program of Zhejiang(No.2023C03149).
文摘Anaerobic fermentation is an efficient method to extract phosphorus from excess sludge,thereby facilitating its recovery and mitigating the phosphorus resource shortage.However,the prevalent metal-bound phosphorus species within sludge was difficult to release into the fermentation liquor.To address this,this study evaluated the enhanced phosphorus release performance from sludge containing iron-phosphorus compounds(Fe-P)via co-fermenting it with agriculture wastes.Specifically,protein-rich feather(Feather Group)and polysaccharide-rich tea residue(Tea Group)was respectively dosed into batch-scale fermentation jar.Results showed that the Feather Group exhibited significantly higher levels of released soluble phosphorus(2.1 folds)and volatile fatty acids(41.4 folds)compared to the Control Group,with concentrations reaching up to 280 mg/L and 9366 mg chemical oxygen demand/L,respectively.The activities ofα-glucosidase,neutral protease and acetate kinase in the Feather group were increased by 11.1%,92.3%and 37.6%,respectively,compared with the Control group.Methanogen abundance decreased while hydrolytic acid-producing bacteria and iron-reducing bacteria increased significantly after supplying agricultural wastes.Metagenomic analysis demonstrated a significant increase in genes related to acetic acid synthesis.Mechanism elucidation suggested that increased iron-reducing bacteria abundance promoted Fe3+reduction into Fe2+,thus enhancing phosphorus release from Fe-P compounds.This work may provide valuable information for developing effective strategy to extract phosphorus resource from complex environmental wastes.
基金financially supported by the National Natural Science Foundation of China(No.22176041,T2421005)National Key R&D Program of China(No.2022YFC3901800)+1 种基金the Fundamental Research Funds for the Central Universities(No.2243200011)Guangzhou Science and Technology Planning Project(No.2023A04J0918).
文摘Wide bandgap semiconductors are typically activated under ultraviolet(UV)light irradiation for volatile organic compounds(VOCs)degradation.However,our previous study discovered that certain VOCs can interact with some wide bandgap semiconductors,formatting an intermediate bandgap between the VOCs and the conduction band of wide bandgap semiconductor,thus inducing visible light activation of the system,and photo-generated electrons are excited by visible light and transferred from the VOCs to the conduction band of semiconductor.In this work,BaTiO_(3),traditionally is not active under visible light irradiation,however showed degradation rates of 100%and 20%for styrene and toluene under visible light,respectively.Density functional theory(DFT)calculations indicate that the adsorption of styrene or toluene on the BaTiO_(3)surface reduces its bandgap from 2.93 eV to 1.36 eV and 2.26 eV,respectively.The intermediate bandgap in this system is primarily formed by the valence band of BaTiO_(3)and the VOCs,and indicating that photo-generated electrons directly transfer from BaTiO_(3)to the VOCs under visible light,inducing degradation reactions of VOCs,i.e.,this work discovered a new transfer pathway of photo-electrons direct from the valence band of BaTiO_(3)to VOCs,while photo-electrons are from VOCs to the conductive band of wide-bandgap semiconductors in our previous work.
基金supported by the Key R&D Plan of Shaanxi Province[key industrial innovation chain(Group)](No.2022ZDLSF07-04).
文摘The third member of Shahejie Formation(also referred to as Sha 3 Member)in Dongpu Depression,China,a volatile,low-permeability oil reservoir with complex fluid compositions,is subjected to high temperature and high pressure(HPHT),which poses significant challenges to conventional water injection.To elucidate flow mechanisms and optimize development strategies,this study integrates constant-rate mercury injection(CRMI),nuclear magnetic resonance(NMR),and HPHT three-phase oil/gas/water relative permeability experiments to analyze pore-throat structures,movable fluid characteristics,and relative permeability.The CRMI results indicate that the reservoir exhibits low porosity and low permeability,with dominant throat radius ranging from 0.6 to 5.0μm,and mean pore-throat radius ratio ranging from 40.303 to 278.320,demonstrating significant microscopic heterogeneity.The NMR results reveal that water-alternating-gas(WAG)injection enhances oil recovery by 16.28%(Sample W1)and 13.52%(Sample W2)compared to conventional water injection,primarily due to the gas phase's low viscosity and high mobility,enabling access to micropores unreachable by water phases.The HPHT three-phase relative permeability tests demonstrate positive correlations between saturation and relative permeability,with oil permeability significantly influenced by three-phase saturation and rock wettability.These findings establish a microscopic seepage model for optimizing enhanced oil recovery(EOR)strategies in volatile reservoirs.
基金supported by the National Science Foundation of China,Grant 32470245.
文摘Angelica L.has attracted global interest for its traditional medicinal uses and commercial values.However,few studies have focused on the metabolomic differences among the Angelica species.In this study,widely targeted metabolomics based on gas chromatography-tandem mass spectrometry was employed to analyze the metabolomes of four Angelica species(Angelicasinensis(Oliv.)Diels(A.sinensis),Angelica biserrata(R.H.Shan &Yuan)C.Q.Yuan & R.H.Shan(A.biserrata),Angelica dahurica(Hoffm.)Benth.& Hook.f.ex Franch.& Sav.(A.dahurica)and Angelica keiskei Koidz.(A.keiskei)).A total of 698 volatile metabolites were identified and classified into fifteen different categories.The metabo-lomic analysis indicated that 7-hydroxycoumarin and Z-ligustilide accumulated at significantly higher levels in A.sinensis,whereas bornyl acetate showed the opposite pattern.Furthermore,a high correspondence between the dendrogram of metabolite contents and phylogenetic positions of the four species.This study provides a comprehensive biochemical map for the exploitation,application and development of the Angelica species as medicinal plants or health-related dietary supplements.
基金supported by the China Agriculture Research System of Ministry of Finance of the People’s Republic of China(MOF)Ministry of Agriculture+1 种基金Rural Affairs of the People’s Republic of China(MARA)(CARS-38)S&T Program of Hebei(215A7101D).
文摘Microbial growth causes lamb spoilage.This study explored the spoilage ability of Latilactobacillus sakei,Serratia proteamaculans and Hafnia proteus in vacuum-packed raw lamb,including growth ability,degradation of protein and lipid,and change of volatile organic compounds(VOCs)profile,meanwhile screened the key VOCs produced by the targeted strains with meat background excluding,finally confirmed the volatile spoilage marker of vacuum-packaged lamb by comparing with our previous work.The results showed that L.sakei,S.proteamaculans and H.proteus had excellent growth ability.L.sakei inoculated group significantly reduced the pH value,showed higher trichloroacetic acid-soluble peptides content,and excellently degraded sarcoplasmic and myofibrillar proteins.About free amino acids,L.sakei significantly degraded serine,arginine and aspartic acid,while S.proteamaculans and H.proteus significantly degraded serine and lysine.In addition,L.sakei had the strongest effect on promoting free fatty acid production,followed by S.proteamaculans and finally H.proteus.Evaluating from various indicators,the co-culture of the three strains did not have any effect.The key volatiles produced by L.sakei were 1-hexanol,acetic acid and hexanoic acid,S.proteamaculans produced 1-hexanol and acetoin,and H.proteus produced 1-hexanol,acetic acid and acetoin.In the end,1-hexanol,hexanoic acid and acetoin were proven to be spoilage markers for vacuum-packaged and chilled lamb.This study can provide fundamental information for inhibiting and rapid identification of spoilage in vacuum-packaged lamb.
基金supported by the National Natural Science Foundation of China(No.82273711).
文摘Existing evidence has demonstrated the association between exposure to volatile organic compounds(VOCs)and osteoporosis(OP)risk,but the underlying mechanistic framework remains unclear.This study aimed to explore potential pathways using adverse outcome pathway(AOP)analysis,and evidence this association in middle-to-old-aged American adults using the updated National Health and Nutrition Examination Survey data.Multivariable-adjusted general linear and weighted quantile sum models were employed to analyze associations of VOC metabolites(VOCMs),representing internal VOCs exposure levels,with OP-related phenotypes.An AOP framework based on network analysis was developed by extracting target genes and phenotypes.Among 3555 American adults aged≥40 years(539 OP participants),we found that increasing urinary 3-and 4-methylhippuric acid,N-acetyl-S-(n-propyl)-l-cysteine(BPMA),and N-acetyl-S-(3-hydroxypropyl)-l-cysteine were associated with elevated OP odds with odds ratios(ORs)(95%confidence intervals,95%CIs)being 1.254(1.016 to 1.548),1.182(1.014 to 1.377),and 1.244(1.029 to 1.505),respectively,per standard deviation.Urinary BPMA and N-acetyl-S-(2-cyanoethyl)-l-cysteine were inversely associated with lumbar spine bone mineral density(BMD),while urinary N-acetyl-S-(2-hydroxypropyl)-l-cysteine was positively associated with hip BMD.Additionally,OP odds increased by 46.0%(95%CI:3.9%to 105.1%)per quartile increment in the VOC mixture.AOP analysis identified 53 target genes and 9 target phenotypes,and 5 of 9 target phenotypes were oxidative stress(OS)-related.Literature and the“AOP 482”framework implied the core role of OS in the VOC exposure and prevalent OP association,with the interleukin-6 as themolecular initiating event.Our findings provided a theoretical basis for further investigation.
