Prolonged exposure to n-butanol, a common hazardous volatile organic compound(VOC) in the environment, can lead to a broad range of adverse health effects. Therefore, detecting n-butanol safely and efficiently at low ...Prolonged exposure to n-butanol, a common hazardous volatile organic compound(VOC) in the environment, can lead to a broad range of adverse health effects. Therefore, detecting n-butanol safely and efficiently at low concentrations becomes critical for both environmental monitoring and human health. In this study, a novel Eu/Ce-codoped MOF-ZnO gas sensor was developed for the sensitive detection of n-butanol gas under ultraviolet activation at ambient temperature. A series of Eu/Ce-ZnO nanomaterials were synthesized via a simple co-precipitation route, by carefully designing the varied mass ratios of Eu and Ce incorporated into pristine ZnO derived from MOF precursors. The gas testing results revealed that introducing an appropriate amount of Eu and Ce would enlarge the specific surface area and enrich the oxygen vacancy content compared to pristine MOF-ZnO. Upon UV irradiation, the 0.03 wt% Eu 0.04 wt% Ce-ZnO sensor achieved a superior response of 611 for100 ppm n-butanol at room temperature, 15.28 times higher than that of pristine MOF-ZnO(40). Furthermore, the sensor presented rapid response/recovery times(15 s/28 s) and excellent selectivity. The above contributions pave the way for the promising development of highly sensitive, ultraviolet-enhanced gas sensors for ambient temperature detection of VOCs.展开更多
BACKGROUND To investigate whether seasonal differences in ambient temperature affect the incidence of early postoperative cognitive dysfunction(POCD)among elderly patients undergoing laparoscopic surgery in tropical r...BACKGROUND To investigate whether seasonal differences in ambient temperature affect the incidence of early postoperative cognitive dysfunction(POCD)among elderly patients undergoing laparoscopic surgery in tropical regions.Additionally,it explored the perioperative risk factors associated with early POCD following abdominal laparoscopic surgery.AIM To investigate the influence of seasonal differences in ambient temperature on POCD of elderly patients METHODS A total of 125 patients aged≥65 years from Hainan Province,China,who underwent laparoscopic surgery under general anesthesia with tracheal intubation,were enrolled. All patients completed the Mini-Mental State Examination one day before surgery and onpostoperative days 1, 3, and 7. A decline of ≥ 2 points from baseline was considered indicative of cognitivedysfunction. Serum levels of S100 calcium binding protein B and neuron-specific enolase were measured usingenzyme-linked immunosorbent assay at three time points: Preoperatively, immediately after extubation, and 24hours postoperatively. Perioperative clinical data were collected to identify potential risk factors for POCD.Propensity score matching (PSM) was performed (1:1, caliper = 0.03), resulting in 41 matched patient pairs betweenwinter and summer groups.RESULTSAfter PSM, baseline characteristics including age, gender, body mass index, education level, comorbidities, andsurgical variables were well balanced between groups. There were no significant differences in the incidence ofPOCD on postoperative days 1, 3, and 7 between patients undergoing laparoscopic surgery in winter vs summer.However, multivariable logistic regression revealed that surgical duration (day 1, P value = 0.049), advanced ageand elevated creatinine (day 3, P value = 0.044, P value = 0.008), and hypoalbuminemia (day 3, P value = 0.042;day7, P value = 0.015) were independently associated with early POCD.CONCLUSIONAmbient temperature differences between winter and summer in tropical regions did not significantly affect theincidence of early POCD in elderly patients undergoing laparoscopic surgery. Nonetheless, age, longer surgicalduration, elevated creatinine, and hypoalbuminemia emerged as key risk factors. These findings underscore theimportance of perioperative optimization to reduce the risk of POCD in elderly patients, regardless of seasonaltemperature variations.展开更多
Catalytic oxidation of biomass-derived 5-hydroxymethylfurfural(HMF)to 2,5-furandicarboxylic acid(FDCA,an alternative bioplastic monomer to petroleum-derived terephthalic acid),has been identified as an important bioma...Catalytic oxidation of biomass-derived 5-hydroxymethylfurfural(HMF)to 2,5-furandicarboxylic acid(FDCA,an alternative bioplastic monomer to petroleum-derived terephthalic acid),has been identified as an important biomass conversion reaction in bio-based polyester industry.However,it is still challenging to acquire a high FDCA yield from the selective oxidation of HMF at low temperatures.Herein,a ternary metal-based catalyst was prepared by loading AuPdPt noble metal nanoparticles on the oxygen-rich vacancy titanium dioxide layer deposited on natural clay mineral halloysite nanotubes(HNTs),and the catalytic activity was examined for air-oxidation of HMF to FDCA in water at ambient temperature(30℃).By adjusting the Au/Pd/Pt ratio,a 93.6%FDCA yield was achieved with the optimal Au_(0.5)Pd_(0.2)Pt_(0.3)/TiO_(2)@HNTs catalyst,which revealed an impressive FDCA formation rate of 67.58 mmol g^(-1)h^(-1)and an excellent TOF value of 17.54 h^(-1)under normal air pressure at 30℃,surpassing the performance of mono-and bimetallic-based catalysts.Theoretical calculation and catalytic performance study clarified the structure-activity relationship.It was found that the ternary metal and oxygen vacancies revealing synergistic enhancement of ambient temperature catalyzed HMF air-oxidation via electronic structure tuning and adsorption intensification.DFT and kinetics study demonstrated that the presence of ternary metal significantly improved the adsorption capacity of substrate and enhanced the rate-determining step of the key intermediate 5-hydroxymethyl-2-furanocarboxylic acid(HMFCA)oxidation when compared to mono-and bimetal.Additionally,the TiO_(2)@HNTs support with high oxygen vacancy concentration facilitated the adsorption of oxygen,synergistically working with the ternary metal to activate and low the energy barriers for the generation of superoxide radical,thus enhancing the FDCA formation.This work offers a novel strategy for designing ternary metal-based catalysts for low-energy catalytic oxidation reactions.展开更多
Ce-doped nanosized ZnO desulfurizer was prepared by homogeneous precipitation,and its desulfurization efficiency at ambient temperature was investigated through dynamic experiments.The results showed that the desulfur...Ce-doped nanosized ZnO desulfurizer was prepared by homogeneous precipitation,and its desulfurization efficiency at ambient temperature was investigated through dynamic experiments.The results showed that the desulfurization activity of nanosized Ce-ZnO had improved greatly,compared to nanosized ZnO desulfurizer.Nanosized Ce-ZnO desulfurizer was characterized by XRD,TPD-MS,XPS,and TEM.The research results indicated that doping Ce decreased the particle size of the nanosized ZnO desulfurizer and ZnS was the principal desulfurization product.There were adsorption complexes of HS and S on the surface of desulfurizer as well.Only a small amount of vapor appeared in the tail gas on the condition of meeting the precision of desulfurization.展开更多
The objective of this paper was to examine the feasibility of partial nitrification from raw domestic wastewater at ambient temperature by aeration control only. Airflow rate was selected as the sole operational param...The objective of this paper was to examine the feasibility of partial nitrification from raw domestic wastewater at ambient temperature by aeration control only. Airflow rate was selected as the sole operational parameter. A 14L sequencing batch reactor was operated at 23℃ for 8 months, with an input of domestic wastewater. There was a prolgrammed decrease of the airflow rate to 28L·h^-1, the corresponding average dissolved oxygen (DO) was 0.32mg·h^-1, and the average nitrite accumulation rate increased to 92.4% in 3 weeks. Subsequently, further increase in the airflow rate to 48L·h^-1 did not destroy the partial nitrification to nitrite, with average DO of 0.60mg·h^-1 and nitrite accumulating rate of 95.6%. The results showed that limited airflow rate to cause oxygen deficiency in the reactor would eventually induce only nitrification to nitrite and not further to nitrate and that this system showed relatively stability at higher airflow rate independent of pH and temperature. About 50% of influent total nitrogen was eliminated coupling with partial nitrification, taking the advantage of low DO during the reaction.展开更多
To investigate the wear resistance of ZG42CrMo in industrial application,the wear behaviors under different normal loads,sliding speeds and ambient temperatures were simulated by an MMU-5G abrasion tester to acquire t...To investigate the wear resistance of ZG42CrMo in industrial application,the wear behaviors under different normal loads,sliding speeds and ambient temperatures were simulated by an MMU-5G abrasion tester to acquire the friction coefficients and wear rates,with the morphology of worn surface observed by scanning electron microscopy(SEM)and chemical composition of worn surface and debris analyzed by X-ray energy dispersive spectroscopy(EDS).Combine with the theory of tribology,finally the regular of environmental factors’influence on material wear behaviors is determined.The results show that the increase of load decreases wear resistance significantly,when the pressure reaches a certain extent,severe spalling occurs on the worn surface;the changes of speed result in the changes of size of abrasive debris,and then effect the wear behaviors,in the increasing process of speed,the wear rate increases firstly and then decreases;the rise of temperature causes changes in wear mechanism,bring forth oxidation film on the worn surface,which leads to significant improvement of the wear resistance of materials under high temperature compared to that under low temperature.展开更多
Turmeric residue(TR), containing residual levels of curcumin, is a solid by-product waste generated after the extraction and separation of curcumin from turmeric root. A feeding trial was conducted to evaluate the e...Turmeric residue(TR), containing residual levels of curcumin, is a solid by-product waste generated after the extraction and separation of curcumin from turmeric root. A feeding trial was conducted to evaluate the effects of TR on the survival of Chinese soft-shelled turtles(SSTs), Pelodiscus sinensis, under a high ambient temperature. A total of 320 female SSTs were assigned randomly to two diets: basal diet(the control group, n=160) and an interventional diet supplemented with 10% TR(the TR group, n=160). Our results demonstrated that supplementation of TR increased the SST survival rate by 135.5%, and superoxide dismutase(SOD) activity of SST liver by 112.8%, and decreased the malondialdehyde(MDA) content of SST liver by 36.4%, compared to the control group. The skin of the SST fed TR showed a golden color. High-performance liquid chromatography(HPLC) analysis indicated that the concentrations of curcumin in TR and the skin of the SST fed TR were(1.69±0.30) and(0.14±0.03) μg/g, respectively. Our observation suggests that supplementation of TR increased the survival rate of SST under high ambient temperatures. We speculated that the increased survival rate and tolerance at the high ambient temperature were associated with the anti-oxidation activity of curcumin from TR. Moreover, curcumin in TR could be deposited in SST skin, which made it more favored in the market of China. Our findings provide new knowledge and evidence to effectively reuse TR as a feed additive in animal and aquatic farming.展开更多
A synthetic wastewater containing phenol as sole substrate was treated in a 2 8 L upflow anaerobic sludge blanket(UASB) reactor at ambient temperature. The operation conditions and phenol removal efficiency were disc...A synthetic wastewater containing phenol as sole substrate was treated in a 2 8 L upflow anaerobic sludge blanket(UASB) reactor at ambient temperature. The operation conditions and phenol removal efficiency were discussed, microbial population in the UASB sludge was identified based on DNA cloning, and pathway of anaerobic phenol degradation was proposed. Phenol in wastewater was degraded in an UASB reactor at loading rate up to 18 gCOD/(L·d), with a 1:1 recycle ratio, at 26±1℃, pH 7 0—7 5. An UASB reactor was able to remove 99% of phenol up to 1226 mg/L in wastewater with 24 h of hydraulic retention time(HRT). For HRT below 24 h, phenol degradation efficiency decreased with HRT, from 95 4% at 16 h to 93 8% at 12 h. It further deteriorated to 88 5% when HRT reached 8 h. When the concentration of influent phenol of the reactor was 1260 mg/L(corresponding COD 3000 mg/L), with the HRT decreasing(from 40 h to 4 h, corresponding COD loading increasing), the biomass yields tended to increase from 0 265 to 3 08 g/(L·d). While at 12 h of HRT, the biomass yield was lower. When HRT was 12 h, the methane yield was 0 308 L/(gCOD removed), which was the highest. Throughout the study, phenol was the sole organic substrate. The effluent contained only residual phenol without any detectable intermediates, such as benzoate, 4 hydrobenzoate or volatile fatty acids(VFAs). Based on DNA cloning analysis, the sludge was composed of five groups of microorganisms. Desulfotomaculum and Clostridium were likely responsible for the conversion of phenol to benzoate, which was further degraded by Syntrophus to acetate and H 2/CO 2. Methanogens lastly converted acetate and H 2/CO 2 to methane. The role of epsilon Proteobacteria was, however, unsure.展开更多
The association between ambient temperature and acute exacerbation of chronic bronchitis (AECB) was still unknown. Therefore, we performed an epidemiological study in a large hospital of Shanghai to explore the rela...The association between ambient temperature and acute exacerbation of chronic bronchitis (AECB) was still unknown. Therefore, we performed an epidemiological study in a large hospital of Shanghai to explore the relationship about temperature and outpatient visit for AECB. We adopted a quasi-Poisson generalized additive models and distributed lag nonlinear models to estimate the accumulative effects of temperature on AECB across multiple days. We found significant non-linear effects of cold temperature on hospital visits for AECB, and the potential effect of cold temperature might last more than 2 weeks. The relative risks of extreme cold (first percentiles of temperature throughout the study period) and cold (10th percentile of temperature) temperature over lags 0-14 d were 2.98 [95% confidence intervals (CI): 1.77, 5.04] and 1.63 (95% Ch 1.21, 2.19), compared with the 25th percentile of temperature. However, we found no positive association between hospital visits and hot weather. This study showed that exposure to both extreme cold and cold temperatures were associated with increased outpatient visits for AECB in a large hospital of Shanghai.展开更多
A novel‐structured Mo‐Cu‐Fe‐O composite was successfully prepared by co‐precipitation and impregnation method.The properties of the as‐prepared samples were determined using X‐ray diffraction,temperature‐progr...A novel‐structured Mo‐Cu‐Fe‐O composite was successfully prepared by co‐precipitation and impregnation method.The properties of the as‐prepared samples were determined using X‐ray diffraction,temperature‐programmed reduction by H2,cyclic voltammetry,and temperature‐programmed desorption by O2.The results showed that Mo6+diffused into the Cu‐Fe‐O crystal lattice and then formed a new crystalline phase of CuMoO4.The Mo‐Cu‐Fe‐O catalyst had redox properties,and its surface contained active sites for oxygen adsorption.In addition,the catalytic activity of the Mo‐Cu‐Fe‐O composite was evaluated by the degradation of Cationic Red GTL,Crystal Violet,and Acid Red in catalytic wet air oxidation(CWAO)at ambient temperature and pressure.The Mo‐Cu‐Fe‐O catalyst showed excellent activity at basic conditions for the degradation of Cationic Red GTL.High removal efficiencies of91.5%and92.8%were achieved for Cationic Red GTL and Crystal Violet,respectively,in wastewater,and the efficiency remained high after seven cycles.However,almost no degradation of Acid Red occurred in the CWAO process.Furthermore,hydroxyl radicals were formed in the CWAO process,which induced the decomposition of the two cationic dyes in wastewater,and the toxicity of their effluents was decreased after degradation.The results indicate that the Mo‐Cu‐Fe‐O composite shows excellent catalytic activity for the treatment of wastewater contaminated with cationic dyes.展开更多
The objective of this study was to evaluate the effects of low ambient temperature (LAT) and dietary vitamin C (VC) sup- plementation on pulmonary vascular remodeling (PVR) and the relative expression of hypoxia...The objective of this study was to evaluate the effects of low ambient temperature (LAT) and dietary vitamin C (VC) sup- plementation on pulmonary vascular remodeling (PVR) and the relative expression of hypoxia inducible factor-la (HIF-la), vascular endothelial growth factor (VEGF) and its receptor 2 (VEGFR-2) mRNA of lungs in 21-d-old broilers. 400 1-d-old male Cobb broilers were assigned randomly to 4 treatments as follows for 21 d: 1 ) LAT and a basal diet; 2) LAT and a basal diet supplemented with 1 000 mg kg-1 VC (LAT+VC); 3) normal ambient temperature (NAT) and a basal diet; 4) NAT and a basal diet supplemented with 1 000 mg kg-1 VC (NAT+VC). Each treatment was composed of 10 replicates of 10 birds per replicate. Samples of lung were collected after the broilers were killed at d 21. LAT increased the ratio of vessel wall area to vessel total area (WA/TA, %) and mean media thickness in pulmonary arterioles (mMTPA, %) (P〈0.05). Dietary VC supplementation decreased mMTPA (P〈0.05), but had no effect on the WA/TA. LAT increased (P〈0.05) the relative mRNA expression of HIF-la, VEGF and VEGFR-2, while adding VC to the diet could decrease (P〈0.05) their relative mRNA expression. A significant positive correlation existed between the level of VEGF mRNA expression and the value of WA/WT (P〈0.05) or mMTPA (P〈0.05). These results suggested LAT resulted in pulmonary vascular remodeling, and the increase of HIF-la, VEGF and VEGFR-2 mRNA expression, and dietary VC supplementation can alleviate pulmonary vascular remodeling in broiler by affecting these gene expression.展开更多
Because of global warming,people have paid more attention to greenhouse gas emitted by vehicles.To quantify the impact of temperature on vehicle CO_(2)emissions,this study was conducted using the world light vehicle t...Because of global warming,people have paid more attention to greenhouse gas emitted by vehicles.To quantify the impact of temperature on vehicle CO_(2)emissions,this study was conducted using the world light vehicle test cycle on two light-duty E10 gasoline vehicles a ambient temperatures of-10,0,23,and 40℃,and found that CO_(2)emission factors of Vehicle1 in the low-speed phase were 22.07%and 20.22%higher than those of Vehicle 2 at cold star and hot start under-10℃.The reason was vehicle 1 had a larger displacement and more friction pairs than vehicle 2.There was the highest CO_(2)emission at the low-speed phase due to low average speed,frequent acceleration,and deceleration.The CO_(2)temperature factor and the ambient temperature had a strong linear correlation(R2=0.99).According to CO_(2)temperature factors and their relationships,CO_(2)emission factors of other ambien temperatures could be calculated when the CO_(2)emission factor of 23℃was obtained,and the method also could be used to obtain the CO_(2)temperature factors of different vehicles.To separate the effect of load setting and temperature variation on CO_(2)emission quantitatively a method was proposed.And results showed that the load setting was dominant for the CO_(2)emission variation.Compared with 23℃,the CO_(2)emission for vehicle 1 caused by load setting variation were 62.83 and 47.42 g/km,respectively at-10 and 0℃,while those fo vehicle 2 were 45.01 and 35.63 g/km,respectively.展开更多
Sodium fluoride was found to be a simple, mild and efficient catalyst for the synthesis of 2,4- disuhstituted 1,3-thiazoles and selenazoles utilizing phenacyl bromides/3-(2-bromoacetyl)-2H-chro- men-2-one and thiour...Sodium fluoride was found to be a simple, mild and efficient catalyst for the synthesis of 2,4- disuhstituted 1,3-thiazoles and selenazoles utilizing phenacyl bromides/3-(2-bromoacetyl)-2H-chro- men-2-one and thioureaJphenylthiourea/selenourea in aqueous methanol at ambient temperature. Analytically pure products are formed within 1-3 rain in excellent yields.展开更多
Background:Previous studies have established a link between fluctuations in climate and increased mortality due to coronary artery disease(CAD).However,there remains a need to explore and clarify the evidence for asso...Background:Previous studies have established a link between fluctuations in climate and increased mortality due to coronary artery disease(CAD).However,there remains a need to explore and clarify the evidence for associations between meteorological changes and hospitalization incidences related to CAD and its subtypes,especially in cold regions.This study aimed to systematically investigate the relationship between exposure to meteorological changes,air pollutants,and hospitalization for CAD in cold regions.Methods:We conducted a cross-sectional study using hospitalization records of 86,483 CAD patients between January 1,2009,and December 31,2019.Poisson regression analysis,based on generalized additive models,was applied to estimating the influence of hospitalization for CAD.Results:Significant associations were found between low ambient temperature[-10℃,RR=1.65;95%CI:(1.28-2.13)]and the incidence of hospitalization for CAD within a lag of 0-14 days.Furthermore,O_(3)[95.50μg/m^(3),RR=12;95%CI:(1.03-1.21)]and NO_(2)[48.70μg/m^(3),RR=1.0895%CI:(1.01-1.15)]levels were identified as primary air pollutants affecting the incidence of CAD,ST-segment-elevation myocardial infarction(STEMI),and non-STEMI(NSTEMI)within the same lag period.Furthermore,O_(3)[95.50μg/m^(3),RR=1.12;95%CI:(1.03-1.21)]and NO_(2)[48.70μg/m^(3),RR=1.0895%CI:(1.01-1.15)]levels were identified as primary air pollutants affecting the incidence of CAD,ST-segment-elevation myocardial infarction(STEMI),and non-STEMI(NSTEMI)within the same lag period.The effect curve of CAD hospitalization incidence significantly increased at lag days 2 and 4 when NO_(2)and O_(3)concentrations were higher,with a pronounced effect at 7 days,dissipating by lag 14 days.No significant associations were observed between exposure to PM,SO_(2),air pressure,humidity,or wind speed and hospitalization incidences due to CAD and its subtypes.Conclusion:Our findings suggest a positive correlation between short-term exposure to low ambient temperatures or air pollutants(O_(3)and NO_(2))and hospitalizations for CAD,STEMI,and NSTEMI.These results could aid the development of effective preparedness strategies for frequent extreme weather events and support clinical and public health practices aimed at reducing the disease burden associated with current and future abnormal weather events.展开更多
In this study,we investigated the effects of high ambient temperature on lipid metabolism in finishing pigs.Sixteen pigs((79.6±1.2) kg) were randomly assigned to two groups:(1) ambient temperature of 30℃ ...In this study,we investigated the effects of high ambient temperature on lipid metabolism in finishing pigs.Sixteen pigs((79.6±1.2) kg) were randomly assigned to two groups:(1) ambient temperature of 30℃ with ad libitum access to feed(HT;n=8) and(2) ambient temperature of 22℃ and fed the average amount consumed by eight pigs in HT group on the previous day(PF;n=8).After 21 days of constant exposure to different environmental conditions,all the pigs were euthanized,and blood and tissue samples were obtained.High ambient temperature increased the proportion of backfat(P=0.04,+21.6%)and flare fat(P〈0.01,+43.3%).Compared with pair-fed pigs,the activities of fatty acid synthase(FAS) and malic enzyme in backfat and flare fat were lower(P〈0.05) in heat-stressed pigs,as were the amounts of acetyl-CoA-carboxylase and FAS in the longissimus muscle(LM),the amount of FAS in backfat(P〈0.01),and FAS activity in the liver(P〈0.01).Ambient temperature did not affect the amount of hormone-sensitive lipase in different tissues.The amount of lipoprotein lipase in flare fat tended to be higher(P=0.09,+28.3%),and the activities of β-hydroxyacyl coenzyme A dehydrogenase in front and back of LM were lower(P〈0.01,-48.3 and-49.8%,respectively) at 30℃ than at 22℃.The plasma concentration of high-density lipoprotein tended to be lower(P=0.08),but the plasma concentrations of very low-density lipoprotein(VLDL)(P=0.09,+50.0%) and nonestesterified fatty acid(NEFA)(P=0.04,+44.2%) were higher in heat-stressed pigs.We concluded that high ambient temperature depressed de novo fatty acid synthesis in both adipose tissues and the liver.However,β-oxidation of fatty acid in skeletal muscles was also inhibited in the high-temperature environment.As a result,more plasma NEFAs were used to synthesize VLDLs in the liver and were absorbed by adipose tissues.This may be one reason that high ambient temperature enhances the accumulation of backfat and flare fat in finishing pigs.展开更多
This paper examines the effects of ambient temperature on the Trans-Amadi gas turbine power station Phase II. The investigation took thirteen (13) months (January 2012 to January 2013) during which plant data were mon...This paper examines the effects of ambient temperature on the Trans-Amadi gas turbine power station Phase II. The investigation took thirteen (13) months (January 2012 to January 2013) during which plant data were monitored and operational Logsheets like turbine logsheets, plant—auxiliaries’ logsheets and generator logsheets were studied. The gas turbine (GT) that was under investigation was GT-2: MS5001 Nuovopignone with designed installed capacity of 25.0 Megawatts (MW). The result of the study shows that a 1℃ rise of the ambient temperature is responsible for the following: 0% - 0.12% decrease in the power output, 0% - 0.12% increase in the power differential, 0% - 1.17% decrease in the thermal efficiency, 0% - 27.18% increase in the heat rate and 0% - 3.57% increase in the specific fuel consumption. An ambient temperature of 30℃ is found to yield minimal fuel consumption.展开更多
A facile, safe and economical reducing agent, sodium hypophosphite(Na H2PO2·H2O), has been successfully employed for ambient temperature living radical copolymerization of styrene(St) and methyl methacrylate...A facile, safe and economical reducing agent, sodium hypophosphite(Na H2PO2·H2O), has been successfully employed for ambient temperature living radical copolymerization of styrene(St) and methyl methacrylate(MMA). Such effective reducing agent significantly improved the reactivity of low reactive St monomers during the copolymerization, where the reactivity ratios of St and MMA were determined to be 0.50 and 0.36 by Finemann-Ross method. Thus the copolymerizations proceeded fast and showed typical living/controlled features, as evidenced by pseudo first-order kinetics of polymerization, linear increase in molecular weight versus monomer conversion, and low polydispersity index values. Effects of the concentration of reducing agent and the monomer feed ratio on the copolymerization were investigated in detail. Furthermore, gel permeation chromatography and 1H-NMR analyses as well as chain extension experiments confirmed the high chain-end functionality of the resultant copolymer.展开更多
The present study demonstrates that the down-regulation of peroxisome proliferator-activated receptor-α(PPARα)results in chronic low ambient temperature(LT)exposure-induced cardiac dysfunction and remodeling,emphasi...The present study demonstrates that the down-regulation of peroxisome proliferator-activated receptor-α(PPARα)results in chronic low ambient temperature(LT)exposure-induced cardiac dysfunction and remodeling,emphasizing the therapeutic potential of PPARαactivation strategies(e.g.,fenofibrate treatment)in LT-associated cardiac injury.展开更多
First-row(3 d)transition metal oxyhydroxides have attracted increasing attention due to their various advantages.Although investigating the oxidation mechanism and processing such materials into hierarchical architect...First-row(3 d)transition metal oxyhydroxides have attracted increasing attention due to their various advantages.Although investigating the oxidation mechanism and processing such materials into hierarchical architectures are greatly desired for their further development,it remains unclear how the oxidation state change occurs,and efforts to produce hierarchical oxyhydroxides in compliance with high ecological and economic standards have progressed slowly.Here,we describe a facile one-step coprecipitation route for the preparation of hierarchical CoOOH,NiOOH and MnOOH,which involves the diffusion of NH_(3)originating from ammonium hydroxide solution into an aqueous solution containing metal ion salts and K_(2)S_(2)O_(8).Comprehensive characterizations by scanning electron microscope,transmission electron microscopy,X-ray diffraction analysis,X-ray photoelectron spectroscopy,ultraviolet-visible spectroscopy and in situ p H measurement demonstrated that K_(2)S_(2)O_(8)induces the oxidation state change of metal ion species after the start of hydrolysis.Meanwhile,it was found that,benefiting from the OH–concentration gradient created by the NH_(3)diffusion method and the suitable growth environment provided by the presence of K_(2)S_(2)O_(8)(high nucleation rate and secondary nucleation),the formation of hierarchical oxyhydroxide structures can be realized in aqueous solution at ambient temperature without the use of heat energy and additional structure-directing agents.The hierarchical CoOOH structures are performed as the electrocatalysts for the oxygen evolution reaction in alkaline media,which exhibit good activity with an overpotential of 320 m V at 10 m A cm^(-2)and a low Tafel slope of 59.6 m V dec^(–1),outperforming many congeneric electrocatalysts.Overall,our study not only provides important insights to understand the formation mechanism of hierarchical oxyhydroxides,but also opens up new opportunities for the preparation of hierarchical oxyhydroxides via a facile,green and low-cost method.展开更多
The effect of different ambient temperatures on the electrochemical properties of La4MgNi17.5C01.5 hydrogen storage alloy was investigated. The X-ray diffraction pattern shows that the alloy consists of LaNis-type pha...The effect of different ambient temperatures on the electrochemical properties of La4MgNi17.5C01.5 hydrogen storage alloy was investigated. The X-ray diffraction pattern shows that the alloy consists of LaNis-type phase and AsB19- type (Ce5C019 + Pr5CO19) phase. With the increase of the ambient temperature, the maximum discharge capacity of the alloy electrodes increases from 353.33 (283 K) to 379.25 mAh/g (308 K), and the cyclic stability (Sloo) of the electrodes decreases from 80.19 (283 K) to 52.04% (308 K) due to the acceleration of pulverization, corrosion and oxidation at higher ambient temperature. Moreover, it is found that the increase of the temperature can accelerate the diffusion rate of hydrogen in the alloy (D) and increase the exchange current density (Io), which are beneficial for improving the activation performance and the high-rate dischargeability (HRD) of the alloy electrodes. The activation cycles of the electrodes decrease from 4 (283 K) to 1 (308 K), and the HRD9oo of the electrodes sharply increases from 66.36 (283 K) to 95.64% (308 K).展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 12304467)the China Postdoctoral Science Foundation (Grant No. 2023M732175)。
文摘Prolonged exposure to n-butanol, a common hazardous volatile organic compound(VOC) in the environment, can lead to a broad range of adverse health effects. Therefore, detecting n-butanol safely and efficiently at low concentrations becomes critical for both environmental monitoring and human health. In this study, a novel Eu/Ce-codoped MOF-ZnO gas sensor was developed for the sensitive detection of n-butanol gas under ultraviolet activation at ambient temperature. A series of Eu/Ce-ZnO nanomaterials were synthesized via a simple co-precipitation route, by carefully designing the varied mass ratios of Eu and Ce incorporated into pristine ZnO derived from MOF precursors. The gas testing results revealed that introducing an appropriate amount of Eu and Ce would enlarge the specific surface area and enrich the oxygen vacancy content compared to pristine MOF-ZnO. Upon UV irradiation, the 0.03 wt% Eu 0.04 wt% Ce-ZnO sensor achieved a superior response of 611 for100 ppm n-butanol at room temperature, 15.28 times higher than that of pristine MOF-ZnO(40). Furthermore, the sensor presented rapid response/recovery times(15 s/28 s) and excellent selectivity. The above contributions pave the way for the promising development of highly sensitive, ultraviolet-enhanced gas sensors for ambient temperature detection of VOCs.
文摘BACKGROUND To investigate whether seasonal differences in ambient temperature affect the incidence of early postoperative cognitive dysfunction(POCD)among elderly patients undergoing laparoscopic surgery in tropical regions.Additionally,it explored the perioperative risk factors associated with early POCD following abdominal laparoscopic surgery.AIM To investigate the influence of seasonal differences in ambient temperature on POCD of elderly patients METHODS A total of 125 patients aged≥65 years from Hainan Province,China,who underwent laparoscopic surgery under general anesthesia with tracheal intubation,were enrolled. All patients completed the Mini-Mental State Examination one day before surgery and onpostoperative days 1, 3, and 7. A decline of ≥ 2 points from baseline was considered indicative of cognitivedysfunction. Serum levels of S100 calcium binding protein B and neuron-specific enolase were measured usingenzyme-linked immunosorbent assay at three time points: Preoperatively, immediately after extubation, and 24hours postoperatively. Perioperative clinical data were collected to identify potential risk factors for POCD.Propensity score matching (PSM) was performed (1:1, caliper = 0.03), resulting in 41 matched patient pairs betweenwinter and summer groups.RESULTSAfter PSM, baseline characteristics including age, gender, body mass index, education level, comorbidities, andsurgical variables were well balanced between groups. There were no significant differences in the incidence ofPOCD on postoperative days 1, 3, and 7 between patients undergoing laparoscopic surgery in winter vs summer.However, multivariable logistic regression revealed that surgical duration (day 1, P value = 0.049), advanced ageand elevated creatinine (day 3, P value = 0.044, P value = 0.008), and hypoalbuminemia (day 3, P value = 0.042;day7, P value = 0.015) were independently associated with early POCD.CONCLUSIONAmbient temperature differences between winter and summer in tropical regions did not significantly affect theincidence of early POCD in elderly patients undergoing laparoscopic surgery. Nonetheless, age, longer surgicalduration, elevated creatinine, and hypoalbuminemia emerged as key risk factors. These findings underscore theimportance of perioperative optimization to reduce the risk of POCD in elderly patients, regardless of seasonaltemperature variations.
基金supported by the National Natural Science Foundation of China(22478167,22278419)the College Students Innovative Practice Plan of Jiangsu University(202410299160Y)+2 种基金the Youth Talent Cultivation Plan of Jiangsu Universitythe Key Core Technology Research(Social Development)Foundation of Suzhou(2023ss06)Collaborative Innovation Center for Water Treatment Technology and Materials and the Special Fund of Henan Key Laboratory of Water Pollution Control and Rehabilitation Technology(CJSZ2024010).
文摘Catalytic oxidation of biomass-derived 5-hydroxymethylfurfural(HMF)to 2,5-furandicarboxylic acid(FDCA,an alternative bioplastic monomer to petroleum-derived terephthalic acid),has been identified as an important biomass conversion reaction in bio-based polyester industry.However,it is still challenging to acquire a high FDCA yield from the selective oxidation of HMF at low temperatures.Herein,a ternary metal-based catalyst was prepared by loading AuPdPt noble metal nanoparticles on the oxygen-rich vacancy titanium dioxide layer deposited on natural clay mineral halloysite nanotubes(HNTs),and the catalytic activity was examined for air-oxidation of HMF to FDCA in water at ambient temperature(30℃).By adjusting the Au/Pd/Pt ratio,a 93.6%FDCA yield was achieved with the optimal Au_(0.5)Pd_(0.2)Pt_(0.3)/TiO_(2)@HNTs catalyst,which revealed an impressive FDCA formation rate of 67.58 mmol g^(-1)h^(-1)and an excellent TOF value of 17.54 h^(-1)under normal air pressure at 30℃,surpassing the performance of mono-and bimetallic-based catalysts.Theoretical calculation and catalytic performance study clarified the structure-activity relationship.It was found that the ternary metal and oxygen vacancies revealing synergistic enhancement of ambient temperature catalyzed HMF air-oxidation via electronic structure tuning and adsorption intensification.DFT and kinetics study demonstrated that the presence of ternary metal significantly improved the adsorption capacity of substrate and enhanced the rate-determining step of the key intermediate 5-hydroxymethyl-2-furanocarboxylic acid(HMFCA)oxidation when compared to mono-and bimetal.Additionally,the TiO_(2)@HNTs support with high oxygen vacancy concentration facilitated the adsorption of oxygen,synergistically working with the ternary metal to activate and low the energy barriers for the generation of superoxide radical,thus enhancing the FDCA formation.This work offers a novel strategy for designing ternary metal-based catalysts for low-energy catalytic oxidation reactions.
基金Project supported by the National Natural Science Foundation of China(50478026)
文摘Ce-doped nanosized ZnO desulfurizer was prepared by homogeneous precipitation,and its desulfurization efficiency at ambient temperature was investigated through dynamic experiments.The results showed that the desulfurization activity of nanosized Ce-ZnO had improved greatly,compared to nanosized ZnO desulfurizer.Nanosized Ce-ZnO desulfurizer was characterized by XRD,TPD-MS,XPS,and TEM.The research results indicated that doping Ce decreased the particle size of the nanosized ZnO desulfurizer and ZnS was the principal desulfurization product.There were adsorption complexes of HS and S on the surface of desulfurizer as well.Only a small amount of vapor appeared in the tail gas on the condition of meeting the precision of desulfurization.
基金Supported by Funding Project for Academic Human Resources Development in Institutions of Higher Leading under the Juris-diction of Beijing Municipality [PHR(IHLB)], the National Natural Science Foundation of China (No.50478040)the Na-tional Key Technologies R&D Program of China (No.2006BAC19B03).
文摘The objective of this paper was to examine the feasibility of partial nitrification from raw domestic wastewater at ambient temperature by aeration control only. Airflow rate was selected as the sole operational parameter. A 14L sequencing batch reactor was operated at 23℃ for 8 months, with an input of domestic wastewater. There was a prolgrammed decrease of the airflow rate to 28L·h^-1, the corresponding average dissolved oxygen (DO) was 0.32mg·h^-1, and the average nitrite accumulation rate increased to 92.4% in 3 weeks. Subsequently, further increase in the airflow rate to 48L·h^-1 did not destroy the partial nitrification to nitrite, with average DO of 0.60mg·h^-1 and nitrite accumulating rate of 95.6%. The results showed that limited airflow rate to cause oxygen deficiency in the reactor would eventually induce only nitrification to nitrite and not further to nitrate and that this system showed relatively stability at higher airflow rate independent of pH and temperature. About 50% of influent total nitrogen was eliminated coupling with partial nitrification, taking the advantage of low DO during the reaction.
基金Sponsored by High Technology Research and Development Program of China(2009AA04Z143)New Century Excellent Talents in University of China(NCET-09-0117)
文摘To investigate the wear resistance of ZG42CrMo in industrial application,the wear behaviors under different normal loads,sliding speeds and ambient temperatures were simulated by an MMU-5G abrasion tester to acquire the friction coefficients and wear rates,with the morphology of worn surface observed by scanning electron microscopy(SEM)and chemical composition of worn surface and debris analyzed by X-ray energy dispersive spectroscopy(EDS).Combine with the theory of tribology,finally the regular of environmental factors’influence on material wear behaviors is determined.The results show that the increase of load decreases wear resistance significantly,when the pressure reaches a certain extent,severe spalling occurs on the worn surface;the changes of speed result in the changes of size of abrasive debris,and then effect the wear behaviors,in the increasing process of speed,the wear rate increases firstly and then decreases;the rise of temperature causes changes in wear mechanism,bring forth oxidation film on the worn surface,which leads to significant improvement of the wear resistance of materials under high temperature compared to that under low temperature.
基金Project supported by the National Natural Science Foundation of China(No.31271848)the Foundation of Fuli Institute of Food Science of Zhejiang University(No.KY201404),China
文摘Turmeric residue(TR), containing residual levels of curcumin, is a solid by-product waste generated after the extraction and separation of curcumin from turmeric root. A feeding trial was conducted to evaluate the effects of TR on the survival of Chinese soft-shelled turtles(SSTs), Pelodiscus sinensis, under a high ambient temperature. A total of 320 female SSTs were assigned randomly to two diets: basal diet(the control group, n=160) and an interventional diet supplemented with 10% TR(the TR group, n=160). Our results demonstrated that supplementation of TR increased the SST survival rate by 135.5%, and superoxide dismutase(SOD) activity of SST liver by 112.8%, and decreased the malondialdehyde(MDA) content of SST liver by 36.4%, compared to the control group. The skin of the SST fed TR showed a golden color. High-performance liquid chromatography(HPLC) analysis indicated that the concentrations of curcumin in TR and the skin of the SST fed TR were(1.69±0.30) and(0.14±0.03) μg/g, respectively. Our observation suggests that supplementation of TR increased the survival rate of SST under high ambient temperatures. We speculated that the increased survival rate and tolerance at the high ambient temperature were associated with the anti-oxidation activity of curcumin from TR. Moreover, curcumin in TR could be deposited in SST skin, which made it more favored in the market of China. Our findings provide new knowledge and evidence to effectively reuse TR as a feed additive in animal and aquatic farming.
文摘A synthetic wastewater containing phenol as sole substrate was treated in a 2 8 L upflow anaerobic sludge blanket(UASB) reactor at ambient temperature. The operation conditions and phenol removal efficiency were discussed, microbial population in the UASB sludge was identified based on DNA cloning, and pathway of anaerobic phenol degradation was proposed. Phenol in wastewater was degraded in an UASB reactor at loading rate up to 18 gCOD/(L·d), with a 1:1 recycle ratio, at 26±1℃, pH 7 0—7 5. An UASB reactor was able to remove 99% of phenol up to 1226 mg/L in wastewater with 24 h of hydraulic retention time(HRT). For HRT below 24 h, phenol degradation efficiency decreased with HRT, from 95 4% at 16 h to 93 8% at 12 h. It further deteriorated to 88 5% when HRT reached 8 h. When the concentration of influent phenol of the reactor was 1260 mg/L(corresponding COD 3000 mg/L), with the HRT decreasing(from 40 h to 4 h, corresponding COD loading increasing), the biomass yields tended to increase from 0 265 to 3 08 g/(L·d). While at 12 h of HRT, the biomass yield was lower. When HRT was 12 h, the methane yield was 0 308 L/(gCOD removed), which was the highest. Throughout the study, phenol was the sole organic substrate. The effluent contained only residual phenol without any detectable intermediates, such as benzoate, 4 hydrobenzoate or volatile fatty acids(VFAs). Based on DNA cloning analysis, the sludge was composed of five groups of microorganisms. Desulfotomaculum and Clostridium were likely responsible for the conversion of phenol to benzoate, which was further degraded by Syntrophus to acetate and H 2/CO 2. Methanogens lastly converted acetate and H 2/CO 2 to methane. The role of epsilon Proteobacteria was, however, unsure.
基金supported by the National Clinical key subject construction funds(occupational disease program)the National Basic Research Program(973 program)of China(2011CB503802)+3 种基金Gong-Yi Program of China Ministry of Environmental Protection(201209008)China Medical Board Collaborating Program(13-152)Public Welfare Research Program of National HealthFamily Planning Commission of China(201402022)
文摘The association between ambient temperature and acute exacerbation of chronic bronchitis (AECB) was still unknown. Therefore, we performed an epidemiological study in a large hospital of Shanghai to explore the relationship about temperature and outpatient visit for AECB. We adopted a quasi-Poisson generalized additive models and distributed lag nonlinear models to estimate the accumulative effects of temperature on AECB across multiple days. We found significant non-linear effects of cold temperature on hospital visits for AECB, and the potential effect of cold temperature might last more than 2 weeks. The relative risks of extreme cold (first percentiles of temperature throughout the study period) and cold (10th percentile of temperature) temperature over lags 0-14 d were 2.98 [95% confidence intervals (CI): 1.77, 5.04] and 1.63 (95% Ch 1.21, 2.19), compared with the 25th percentile of temperature. However, we found no positive association between hospital visits and hot weather. This study showed that exposure to both extreme cold and cold temperatures were associated with increased outpatient visits for AECB in a large hospital of Shanghai.
基金supported by the National Natural Science Foundation of China(51678511,51308484)the Natural Science Foundation of Hunan Province(13JJ4049)+3 种基金the Education Department Fund of Hunan Province(14C1094)the Open Fund of Key Laboratory of Mineralogy and Metallogeny in Chinese Academy of Sciences(KLMM20150104)the Major Talent Training Program of Xiangtan University(16PYZ09)the Specialized Research Fund for the Doctoral Program of Xiangtan University(12QDZ18)~~
文摘A novel‐structured Mo‐Cu‐Fe‐O composite was successfully prepared by co‐precipitation and impregnation method.The properties of the as‐prepared samples were determined using X‐ray diffraction,temperature‐programmed reduction by H2,cyclic voltammetry,and temperature‐programmed desorption by O2.The results showed that Mo6+diffused into the Cu‐Fe‐O crystal lattice and then formed a new crystalline phase of CuMoO4.The Mo‐Cu‐Fe‐O catalyst had redox properties,and its surface contained active sites for oxygen adsorption.In addition,the catalytic activity of the Mo‐Cu‐Fe‐O composite was evaluated by the degradation of Cationic Red GTL,Crystal Violet,and Acid Red in catalytic wet air oxidation(CWAO)at ambient temperature and pressure.The Mo‐Cu‐Fe‐O catalyst showed excellent activity at basic conditions for the degradation of Cationic Red GTL.High removal efficiencies of91.5%and92.8%were achieved for Cationic Red GTL and Crystal Violet,respectively,in wastewater,and the efficiency remained high after seven cycles.However,almost no degradation of Acid Red occurred in the CWAO process.Furthermore,hydroxyl radicals were formed in the CWAO process,which induced the decomposition of the two cationic dyes in wastewater,and the toxicity of their effluents was decreased after degradation.The results indicate that the Mo‐Cu‐Fe‐O composite shows excellent catalytic activity for the treatment of wastewater contaminated with cationic dyes.
基金supported by grants from the National Natural Science Foundation of China (31101733)
文摘The objective of this study was to evaluate the effects of low ambient temperature (LAT) and dietary vitamin C (VC) sup- plementation on pulmonary vascular remodeling (PVR) and the relative expression of hypoxia inducible factor-la (HIF-la), vascular endothelial growth factor (VEGF) and its receptor 2 (VEGFR-2) mRNA of lungs in 21-d-old broilers. 400 1-d-old male Cobb broilers were assigned randomly to 4 treatments as follows for 21 d: 1 ) LAT and a basal diet; 2) LAT and a basal diet supplemented with 1 000 mg kg-1 VC (LAT+VC); 3) normal ambient temperature (NAT) and a basal diet; 4) NAT and a basal diet supplemented with 1 000 mg kg-1 VC (NAT+VC). Each treatment was composed of 10 replicates of 10 birds per replicate. Samples of lung were collected after the broilers were killed at d 21. LAT increased the ratio of vessel wall area to vessel total area (WA/TA, %) and mean media thickness in pulmonary arterioles (mMTPA, %) (P〈0.05). Dietary VC supplementation decreased mMTPA (P〈0.05), but had no effect on the WA/TA. LAT increased (P〈0.05) the relative mRNA expression of HIF-la, VEGF and VEGFR-2, while adding VC to the diet could decrease (P〈0.05) their relative mRNA expression. A significant positive correlation existed between the level of VEGF mRNA expression and the value of WA/WT (P〈0.05) or mMTPA (P〈0.05). These results suggested LAT resulted in pulmonary vascular remodeling, and the increase of HIF-la, VEGF and VEGFR-2 mRNA expression, and dietary VC supplementation can alleviate pulmonary vascular remodeling in broiler by affecting these gene expression.
基金supported by the National Natural Science Foundation of China(No.52172337)the National Engineering Laboratory for Mobile Source Emission Control Technology(No.NELMS2018A17)the National Key Research and Development Project of China(No.2018YFE0106800-001)。
文摘Because of global warming,people have paid more attention to greenhouse gas emitted by vehicles.To quantify the impact of temperature on vehicle CO_(2)emissions,this study was conducted using the world light vehicle test cycle on two light-duty E10 gasoline vehicles a ambient temperatures of-10,0,23,and 40℃,and found that CO_(2)emission factors of Vehicle1 in the low-speed phase were 22.07%and 20.22%higher than those of Vehicle 2 at cold star and hot start under-10℃.The reason was vehicle 1 had a larger displacement and more friction pairs than vehicle 2.There was the highest CO_(2)emission at the low-speed phase due to low average speed,frequent acceleration,and deceleration.The CO_(2)temperature factor and the ambient temperature had a strong linear correlation(R2=0.99).According to CO_(2)temperature factors and their relationships,CO_(2)emission factors of other ambien temperatures could be calculated when the CO_(2)emission factor of 23℃was obtained,and the method also could be used to obtain the CO_(2)temperature factors of different vehicles.To separate the effect of load setting and temperature variation on CO_(2)emission quantitatively a method was proposed.And results showed that the load setting was dominant for the CO_(2)emission variation.Compared with 23℃,the CO_(2)emission for vehicle 1 caused by load setting variation were 62.83 and 47.42 g/km,respectively at-10 and 0℃,while those fo vehicle 2 were 45.01 and 35.63 g/km,respectively.
基金the Ministry of Human Resource Development for their support
文摘Sodium fluoride was found to be a simple, mild and efficient catalyst for the synthesis of 2,4- disuhstituted 1,3-thiazoles and selenazoles utilizing phenacyl bromides/3-(2-bromoacetyl)-2H-chro- men-2-one and thioureaJphenylthiourea/selenourea in aqueous methanol at ambient temperature. Analytically pure products are formed within 1-3 rain in excellent yields.
基金This research was partially supported by the National Natural Science Foundation of China(No.72074065)the Harbin Medical University Innovative Scientific Research Funding Project(No.0202-31041220023).
文摘Background:Previous studies have established a link between fluctuations in climate and increased mortality due to coronary artery disease(CAD).However,there remains a need to explore and clarify the evidence for associations between meteorological changes and hospitalization incidences related to CAD and its subtypes,especially in cold regions.This study aimed to systematically investigate the relationship between exposure to meteorological changes,air pollutants,and hospitalization for CAD in cold regions.Methods:We conducted a cross-sectional study using hospitalization records of 86,483 CAD patients between January 1,2009,and December 31,2019.Poisson regression analysis,based on generalized additive models,was applied to estimating the influence of hospitalization for CAD.Results:Significant associations were found between low ambient temperature[-10℃,RR=1.65;95%CI:(1.28-2.13)]and the incidence of hospitalization for CAD within a lag of 0-14 days.Furthermore,O_(3)[95.50μg/m^(3),RR=12;95%CI:(1.03-1.21)]and NO_(2)[48.70μg/m^(3),RR=1.0895%CI:(1.01-1.15)]levels were identified as primary air pollutants affecting the incidence of CAD,ST-segment-elevation myocardial infarction(STEMI),and non-STEMI(NSTEMI)within the same lag period.Furthermore,O_(3)[95.50μg/m^(3),RR=1.12;95%CI:(1.03-1.21)]and NO_(2)[48.70μg/m^(3),RR=1.0895%CI:(1.01-1.15)]levels were identified as primary air pollutants affecting the incidence of CAD,ST-segment-elevation myocardial infarction(STEMI),and non-STEMI(NSTEMI)within the same lag period.The effect curve of CAD hospitalization incidence significantly increased at lag days 2 and 4 when NO_(2)and O_(3)concentrations were higher,with a pronounced effect at 7 days,dissipating by lag 14 days.No significant associations were observed between exposure to PM,SO_(2),air pressure,humidity,or wind speed and hospitalization incidences due to CAD and its subtypes.Conclusion:Our findings suggest a positive correlation between short-term exposure to low ambient temperatures or air pollutants(O_(3)and NO_(2))and hospitalizations for CAD,STEMI,and NSTEMI.These results could aid the development of effective preparedness strategies for frequent extreme weather events and support clinical and public health practices aimed at reducing the disease burden associated with current and future abnormal weather events.
基金The National Basic Research Program of China (2012CB124700)the Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(ASTIP-IAS07) supported the research
文摘In this study,we investigated the effects of high ambient temperature on lipid metabolism in finishing pigs.Sixteen pigs((79.6±1.2) kg) were randomly assigned to two groups:(1) ambient temperature of 30℃ with ad libitum access to feed(HT;n=8) and(2) ambient temperature of 22℃ and fed the average amount consumed by eight pigs in HT group on the previous day(PF;n=8).After 21 days of constant exposure to different environmental conditions,all the pigs were euthanized,and blood and tissue samples were obtained.High ambient temperature increased the proportion of backfat(P=0.04,+21.6%)and flare fat(P〈0.01,+43.3%).Compared with pair-fed pigs,the activities of fatty acid synthase(FAS) and malic enzyme in backfat and flare fat were lower(P〈0.05) in heat-stressed pigs,as were the amounts of acetyl-CoA-carboxylase and FAS in the longissimus muscle(LM),the amount of FAS in backfat(P〈0.01),and FAS activity in the liver(P〈0.01).Ambient temperature did not affect the amount of hormone-sensitive lipase in different tissues.The amount of lipoprotein lipase in flare fat tended to be higher(P=0.09,+28.3%),and the activities of β-hydroxyacyl coenzyme A dehydrogenase in front and back of LM were lower(P〈0.01,-48.3 and-49.8%,respectively) at 30℃ than at 22℃.The plasma concentration of high-density lipoprotein tended to be lower(P=0.08),but the plasma concentrations of very low-density lipoprotein(VLDL)(P=0.09,+50.0%) and nonestesterified fatty acid(NEFA)(P=0.04,+44.2%) were higher in heat-stressed pigs.We concluded that high ambient temperature depressed de novo fatty acid synthesis in both adipose tissues and the liver.However,β-oxidation of fatty acid in skeletal muscles was also inhibited in the high-temperature environment.As a result,more plasma NEFAs were used to synthesize VLDLs in the liver and were absorbed by adipose tissues.This may be one reason that high ambient temperature enhances the accumulation of backfat and flare fat in finishing pigs.
文摘This paper examines the effects of ambient temperature on the Trans-Amadi gas turbine power station Phase II. The investigation took thirteen (13) months (January 2012 to January 2013) during which plant data were monitored and operational Logsheets like turbine logsheets, plant—auxiliaries’ logsheets and generator logsheets were studied. The gas turbine (GT) that was under investigation was GT-2: MS5001 Nuovopignone with designed installed capacity of 25.0 Megawatts (MW). The result of the study shows that a 1℃ rise of the ambient temperature is responsible for the following: 0% - 0.12% decrease in the power output, 0% - 0.12% increase in the power differential, 0% - 1.17% decrease in the thermal efficiency, 0% - 27.18% increase in the heat rate and 0% - 3.57% increase in the specific fuel consumption. An ambient temperature of 30℃ is found to yield minimal fuel consumption.
基金financially supported by the National Natural Science Foundation of China(No.21074127)
文摘A facile, safe and economical reducing agent, sodium hypophosphite(Na H2PO2·H2O), has been successfully employed for ambient temperature living radical copolymerization of styrene(St) and methyl methacrylate(MMA). Such effective reducing agent significantly improved the reactivity of low reactive St monomers during the copolymerization, where the reactivity ratios of St and MMA were determined to be 0.50 and 0.36 by Finemann-Ross method. Thus the copolymerizations proceeded fast and showed typical living/controlled features, as evidenced by pseudo first-order kinetics of polymerization, linear increase in molecular weight versus monomer conversion, and low polydispersity index values. Effects of the concentration of reducing agent and the monomer feed ratio on the copolymerization were investigated in detail. Furthermore, gel permeation chromatography and 1H-NMR analyses as well as chain extension experiments confirmed the high chain-end functionality of the resultant copolymer.
基金supported by the National Natural Science Foundation of China(81800326)the Innovation and Cultivation Fund of the 7th Medical Center of Chinese PLA General Hospital+1 种基金the Open Project of State Key Laboratory of Military Stomatology(2018KA02)the Military Medical Science and Technology Youth Training Program(21QNPY116)。
文摘The present study demonstrates that the down-regulation of peroxisome proliferator-activated receptor-α(PPARα)results in chronic low ambient temperature(LT)exposure-induced cardiac dysfunction and remodeling,emphasizing the therapeutic potential of PPARαactivation strategies(e.g.,fenofibrate treatment)in LT-associated cardiac injury.
基金funded by the Deutsche Forschungsgemeinschaft DFG and the Sino-German Center for Research Promotion(Grants GZ 1351 and CO 194/19-1)funded by a Chinese Scholarship Council stipend。
文摘First-row(3 d)transition metal oxyhydroxides have attracted increasing attention due to their various advantages.Although investigating the oxidation mechanism and processing such materials into hierarchical architectures are greatly desired for their further development,it remains unclear how the oxidation state change occurs,and efforts to produce hierarchical oxyhydroxides in compliance with high ecological and economic standards have progressed slowly.Here,we describe a facile one-step coprecipitation route for the preparation of hierarchical CoOOH,NiOOH and MnOOH,which involves the diffusion of NH_(3)originating from ammonium hydroxide solution into an aqueous solution containing metal ion salts and K_(2)S_(2)O_(8).Comprehensive characterizations by scanning electron microscope,transmission electron microscopy,X-ray diffraction analysis,X-ray photoelectron spectroscopy,ultraviolet-visible spectroscopy and in situ p H measurement demonstrated that K_(2)S_(2)O_(8)induces the oxidation state change of metal ion species after the start of hydrolysis.Meanwhile,it was found that,benefiting from the OH–concentration gradient created by the NH_(3)diffusion method and the suitable growth environment provided by the presence of K_(2)S_(2)O_(8)(high nucleation rate and secondary nucleation),the formation of hierarchical oxyhydroxide structures can be realized in aqueous solution at ambient temperature without the use of heat energy and additional structure-directing agents.The hierarchical CoOOH structures are performed as the electrocatalysts for the oxygen evolution reaction in alkaline media,which exhibit good activity with an overpotential of 320 m V at 10 m A cm^(-2)and a low Tafel slope of 59.6 m V dec^(–1),outperforming many congeneric electrocatalysts.Overall,our study not only provides important insights to understand the formation mechanism of hierarchical oxyhydroxides,but also opens up new opportunities for the preparation of hierarchical oxyhydroxides via a facile,green and low-cost method.
基金financially supported by the National Natural Science Foundation of China(No.50901036)Project of Jiangsu University of Science and Technology(No.YCX 15S-18)Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘The effect of different ambient temperatures on the electrochemical properties of La4MgNi17.5C01.5 hydrogen storage alloy was investigated. The X-ray diffraction pattern shows that the alloy consists of LaNis-type phase and AsB19- type (Ce5C019 + Pr5CO19) phase. With the increase of the ambient temperature, the maximum discharge capacity of the alloy electrodes increases from 353.33 (283 K) to 379.25 mAh/g (308 K), and the cyclic stability (Sloo) of the electrodes decreases from 80.19 (283 K) to 52.04% (308 K) due to the acceleration of pulverization, corrosion and oxidation at higher ambient temperature. Moreover, it is found that the increase of the temperature can accelerate the diffusion rate of hydrogen in the alloy (D) and increase the exchange current density (Io), which are beneficial for improving the activation performance and the high-rate dischargeability (HRD) of the alloy electrodes. The activation cycles of the electrodes decrease from 4 (283 K) to 1 (308 K), and the HRD9oo of the electrodes sharply increases from 66.36 (283 K) to 95.64% (308 K).