With the development of tourism at home and abroad,Rapeseed(Brassica napus)has become an important ornamental plant.However,its ornamental value at the inflorescence stage is greatly reduced by Sclerotinia sclerotioru...With the development of tourism at home and abroad,Rapeseed(Brassica napus)has become an important ornamental plant.However,its ornamental value at the inflorescence stage is greatly reduced by Sclerotinia sclerotiorum.Identification of important genes in the defense responses is critical for molecular breeding,which is an important strategy for controlling the disease.In this study,we isolated a B.napus WRKY transcription factor gene,BnaWRKY75.BnaWRKY75 was found to encode a nucleus-localized protein and exhibited relatively high expression in the stems.Arabidopsis thaliana transgenic plants expressing BnaWRKY75 showed enhanced resistance to S.sclerotiorum,and both ProBnaWRKY75:GUS and gene expression analyses showed that BnaWRKY75 was highly responsive to S.sclerotiorum infection,indicating the involvement of BnaWRKY75 in response to this infection.Furthermore,overexpression(OE)of BnaWRKY75 in B.napus significantly enhanced the resistance to S.sclerotiorum,whereas the resistance was reduced in RNAi transgenic B.napus plants.Moreover,the BnaWRKY75-OE B.napus plants exhibited constitutive activation of salicylic acid-,jasmonic acid-,and ethylene-mediated defense responses and the inhibition of both H_(2)O_(2)and O_(2)·^(-)accumulation in response to this pathogen.By contrast,BnaWRKY75-RNAi plants showed a reverse pattern,suggesting that BnaWRKY75 is involved in hormonal signaling pathways and in the control of reactive oxygen species accumulation.In conclusion,these data indicate that BnaWRKY75,a regulator of multiple defense responses,positively regulates resistance against S.sclerotiorum,which may guide the improvement of resistance in rapeseed.展开更多
Rice(Oryza sativa L.)is a globally important food crop.Its bran oil has high nutritional value,but with a low content of oleic acid and a high content of linoleic acid,which affects the stability and shelf life of the...Rice(Oryza sativa L.)is a globally important food crop.Its bran oil has high nutritional value,but with a low content of oleic acid and a high content of linoleic acid,which affects the stability and shelf life of the oil(Warner et al.2008;Liang et al.2017;Doureradjou and Koner 2020;Ghasemzadeh et al.2020).The fatty acid composition of rice bran oil is one of the healthiest edible oils due to its balanced source of saturated,monounsaturated,and polyunsaturated fatty acids with a ratio of 0.6:1.1:1(Liang et al.2017;Awad et al.2022).展开更多
Herein, the electrochemical behaviors of Sr on inert W electrode and reactive Zn/Al electrodes were systematically investig-ated in LiCl–KCl–SrCl2molten salts at 773 K using various electrochemical methods. The chem...Herein, the electrochemical behaviors of Sr on inert W electrode and reactive Zn/Al electrodes were systematically investig-ated in LiCl–KCl–SrCl2molten salts at 773 K using various electrochemical methods. The chemical reaction potentials of Li and Sr on re-active Zn/Al electrodes were determined. We observed that Sr could be extracted by decreasing the activity of the deposited metal Sr onthe reactive electrode, although the standard reduction potential of Sr(II)/Sr was more negative than that of Li(I)/Li. The electrochemicalextraction products of Sr on reactive Zn and Al electrodes were Zn13Sr and Al4Sr, respectively, with no codeposition of Li observed.Based on the density functional theory calculations, both Zn13Sr and Al4Sr were identified as stable intermetallic compounds with Zn-/Al-rich phases. In LiCl–KCl molten salt containing 3wt% SrCl2, the coulombic efficiency of Sr in the Zn electrode was ~54%. The depolar-ization values for Sr on Zn and Al electrodes were 0.864 and 0.485 V, respectively, exhibiting a stronger chemical interaction between Znand Sr than between Al and Sr. This study suggests that using reactive electrodes can facilitate extraction of Sr accumulated while elec-trorefining molten salts, thereby enabling the purification and reuse of the salt and decreasing the volume of the nuclear waste.展开更多
Ripening of the model fruit tomato(Solanum lycopersicum)is controlled by a transcription factor network including NAC(NAM,ATAF1/2,and CUC2)domain proteins such as No-ripening(NOR),SlNAC1,and SlNAC4,but very little is ...Ripening of the model fruit tomato(Solanum lycopersicum)is controlled by a transcription factor network including NAC(NAM,ATAF1/2,and CUC2)domain proteins such as No-ripening(NOR),SlNAC1,and SlNAC4,but very little is known about the NAC targets or how they regulate ripening.Here,we conducted a systematic search of fruit-expressed NAC genes and showed that silencing NOR-like1(Solyc07g063420)using virus-induced gene silencing(VIGS)inhibited specific aspects of ripening.Ripening initiation was delayed by 14 days when NOR-like1 function was inactivated by CRISPR/Cas9 and fruits showed obviously reduced ethylene production,retarded softening and chlorophyll loss,and reduced lycopene accumulation.RNA-sequencing profiling and gene promoter analysis suggested that genes involved in ethylene biosynthesis(SlACS2,SlACS4),color formation(SlGgpps2,SlSGR1),and cell wall metabolism(SlPG2a,SlPL,SlCEL2,and SlEXP1)are direct targets of NOR-like1.Electrophoretic mobility shift assays(EMSA),chromatin immunoprecipitation-quantitative PCR(ChIP-qPCR),and dual-luciferase reporter assay(DLR)confirmed that NOR-like1 bound to the promoters of these genes both in vitro and in vivo,and activated their expression.Our findings demonstrate that NOR-like1 is a new positive regulator of tomato fruit ripening,with an important role in the transcriptional regulatory network.展开更多
Non-aqueous extraction(NAE)of bitumen from oil sands has been gaining great attention from both the industry and academia as an alternative to the water-based extraction.A fine solids removal step is important for a N...Non-aqueous extraction(NAE)of bitumen from oil sands has been gaining great attention from both the industry and academia as an alternative to the water-based extraction.A fine solids removal step is important for a NAE process in order to obtain high-quality bitumen product,which,however,remains a great challenge to reduce the fine solids content to the desired level.Here,we introduce a strategy of destabilizing the bitumen-coated silica particles in toluene with the addition of water and biomolecules extracted from Cyamopsiste tragonolobuosr L.Taup.,i.e.,high molecular weight guar gum(HGG)and low molecular weight guar gum(LGG),respectively.By virtue of sedimentation tests and focused beam reflectance measurement analysis,we demonstrate that the introduced water droplets modified with these biomolecules can facilitate the settling of the solid particles in toluene although the underlying mechanisms differ between these two biomolecule cases.Specifically,in the case of LGG,the added water droplets with the interfacial amphiphilic LGG can strengthen the attachment of solid particles from bulk toluene to the LGG surface.This research work provides useful insight into the development of effective approaches for destabilization and removal of bitumen-coated fine solids from NAE bitumen.展开更多
An acrylic modified pumpkin vine-based biochar(p-PVB-PAA) is synthesized by non-thermal plasma-grafting modification of pumpkin vine-based biochar(PVB) for the removal of uranyl from an aqueous solution. Microscopic c...An acrylic modified pumpkin vine-based biochar(p-PVB-PAA) is synthesized by non-thermal plasma-grafting modification of pumpkin vine-based biochar(PVB) for the removal of uranyl from an aqueous solution. Microscopic characterization reveals that compared to PVB the surface of p-PVBPAA has more oxygen-containing functional groups by strong chemical bonding and the specific surface area is increased to 275.3 m^2 g^-1 from 3.8 m^2g^-1. It is found that p-PVB-PAA showed a much higher maximum adsorption capacity for uranyl from aqueous solutions than PVB, which were207.02 mg g^-1 and 67.58 mg g^-1 at pH=5 and 298 K, respectively. Moreover, the adsorption behavior follows a pseudo-second-order kinetics model and the Langmuir adsorption model.Additionally, macroscopic experiments and spectroscopic studies verified that the significantly improved adsorption performance of the p-PVB-PAA is due to surface complexation and electrostatic interactions. Furthermore, the very high removal efficiency and excellent regeneration ability(the percentage of the removal still remained at nearly 90% after five cycles) makes this low-cost, easily obtained, and environmentally friendly material attractive for commercial application.展开更多
Brassica napus L(rapeseed)is one of the most important oil crops with large cultivated area in China.Seed size and seed weight play crucial roles for yield and harvest.In this study,a type of 15 bp-deletion in BnaGRF7...Brassica napus L(rapeseed)is one of the most important oil crops with large cultivated area in China.Seed size and seed weight play crucial roles for yield and harvest.In this study,a type of 15 bp-deletion in BnaGRF7.CO2 coding region was identified through sequence alignment of BnaGRF7.C02 in 42 rapeseed varieties,and associ-ation analysis indicated that the 15 bp-deletion was related to the rapeseed Thousand-Seed Weight(TSW)phenotype.Furthermore,we developed two InDel markers to identify this 15 bp InDel.The tissue-specific expression patterns showed that BnaGRF7.C02 prominently expressed in the late stage of seed development.These findings may assist in InDel markers-based breeding efforts to select higher TWS varieties and improve the crop yield of B.nqpus.展开更多
Extraction of uranium from radioactive waste-water is of significant importance for environmental protection and the recovery of uranium resource.Different from the previous reports to use the solid absorbent/photocat...Extraction of uranium from radioactive waste-water is of significant importance for environmental protection and the recovery of uranium resource.Different from the previous reports to use the solid absorbent/photocatalyst for U(VI)removal,herein,we proposed a new eco-friendly method for the rapid and selective extraction of uranium from aqueous solutions under visible light without solid materials.At optimal pH value and in the presence of organics like alcohols,the U(VI)could be extracted efficiently to form brown uranium solid over wide uranium concentrations under anaerobic condition and visible light,by utilizing the excitation of the given U(VI)species.With comprehensive modelling of the electronic ultraviolet-visible(UV-Vis)properties,it is proved that pH adjusting towards U(VI)could induce efficient ligand-to-metal-charge-transfer(LMCT)within the uranyl complex under visible light and the reduction of U(VI)to form U(V),which can be transformed into U(IV)via disproportionation reaction.The resulting U(IV)in solid phase makes the extraction much more convenient in operation.More importantly,the excellent selectivity for uranium extraction over interfering alkali metal ions,transition metal ions and the lanthanide metal ions shows a powerful application potential.展开更多
Among the unresolved issues in the study of relaxor ferroelectrics is the role of freezing temperature,across which the dynamics of polarization reversal in relaxor ferroelectrics changes.The presence of this freezing...Among the unresolved issues in the study of relaxor ferroelectrics is the role of freezing temperature,across which the dynamics of polarization reversal in relaxor ferroelectrics changes.The presence of this freezing temperature is best manifested by the appearance of a double polarization hysteresis loop just above the freezing temperature.Given that the polarization pinching evolving into a double hysteresis starts well below the freezing temperature,there exists a transient temperature regime between the nonergodic and the ergodic relaxor states.To clarify the role of the freezing temperature on the pinching,the polarization reversal near the freezing temperature of relaxor(Pb_(1-x)La_(x))(Zr_(1-y)T_(y))_(1-x/4)O_(3)(PLZT)was monitored using three in situ electric field methods:electrocaloric effect,neutron diffraction,and transmission electron microscopy.We demonstrate that the pinching results from a two-step process,1)domain detexturization in the ferroelectric state and 2)miniaturization of domains.This observation explains the recently reported gap between the depolarization temperature T_(d) and the ferroelectric-torelaxor transition temperature T_(F-R) in lead-free relaxors.We further show that T_(d) and T_(F-R),which have long been considered identical in lead-based relaxors,are not the same.The current study suggests that the mismatch between T_(d) and TF-R is an inherent feature in both lead-based and lead-free relaxor ferroelectrics.展开更多
Metal-enhanced photocatalysis has recently received increasing interest,mainly due to the ability of metal to directly or indirectly degrade pollutants.In this review,we briefly review the recent breakthroughs in meta...Metal-enhanced photocatalysis has recently received increasing interest,mainly due to the ability of metal to directly or indirectly degrade pollutants.In this review,we briefly review the recent breakthroughs in metal-enhanced photocatalysis.We discussed the recent progress of surface plasmon resonance(SPR)effect and small size effect of metal nanoparticles on photocatalysis;in particular,we focus on elucidating the mechanism of energy transfer and hot electron injection/transfer effect of metal nanoparticles and clusters while as photocatalysts or as cophotocatalysts.Finally,we discuss the potential applications of metal-enhanced photocatalysis,and we also offer some perspectives for further investigations.展开更多
The application of nanomaterials in energy and environmental fields has recently made great progress.As a key element in the nuclear industry,the discharge of uranium(U(VI))contained wastewater usually induces environ...The application of nanomaterials in energy and environmental fields has recently made great progress.As a key element in the nuclear industry,the discharge of uranium(U(VI))contained wastewater usually induces environmental issues and waste of resources.Although the catalytically generated H_(2)O_(2)by nanomaterials has recently shown application potential in extracting U(VI)from water,low-cost and highly efficient nanocatalysts are still urgently needed.In this work,a cheap and readily available piezocatalyst of calcium phosphate nanorods was successfully fabricated by calcining chicken bones.Under ultrasonication,H_(2)O_(2)was produced and used to extract U(VI)from water.It is worth noting that the yield of H_(2)O_(2)reached 179.7μmol·g^(−1)·h^(−1),and the extraction efficiency of U(VI)in water reached 97.16%(100 ppm)within 330 min.Through the capture and quantitative analysis of the active species,it is found that the generation of H_(2)O_(2)depends on the combination of soluble oxygen and piezoelectrons,which thus dominates the extraction of U(VI).This simple and powerful piezocatalytic strategy greatly reduces the cost of H_(2)O_(2)production for U(VI)extraction in water,and is of great significance for the treatment of U(VI)-containing wastewater.展开更多
Background:MLH1 promoter methylation analysis is recommended in screening for Lynch syndrome(LS)in patients with MLH1-deficient colorectal cancer(CRC).The study aims to identify specific methylation regions in the MLH...Background:MLH1 promoter methylation analysis is recommended in screening for Lynch syndrome(LS)in patients with MLH1-deficient colorectal cancer(CRC).The study aims to identify specific methylation regions in the MLH1 promoter and to evaluate the clinicopathologic characteristics of and prognosis for patients with MLH1 methylation.Methods:A total of 580 CRC cases were included.The DNA mismatch repair(MMR)protein expression was assessed by using immunohistochemistry(IHC).The methylation status of the Regions A,B,C,D,and E in the MLH1 promoter was tested by using bisulfite sequencing PCR.The specificities of the five regions were calculated.Associations between MLH1 methylation and clinicopathologic characteristics were evaluated.Kaplan-Meier analyses for overall survival(OS)were carried out.Results:In 580 CRC cases,the specificities of the methylation test in Regions D and E were both 97.8%.In the MLH1-deficient CRCs,the frequencies of MLH1 methylation and BRAFV600E mutation were 52.6%and 14.6%,respectively;BRAFV600E mutation occurred in 27.7%of patients with MLH1-methylated CRC.In the MMR-deficient patients,compared with MLH1 unmethylation,MLH1 methylation was more common in patients who were aged≥50years,female,had no family history of LS-related tumors,and had tumors located at the right colon.In the MMR-deficient patients,the MLH1-methylated cases had lower OS rates than the unmethylated cases with a family history of LS-related tumors(P=0.047).Conclusions:Regions D and E in the MLH1 promoter are recommended for determining the MLH1 methylation status in screening for LS in MLH1-deficient CRC.In MMR-deficient patients,the MLH1-methylated cases had a worse OS than the unmethylated cases with a family history of LS-related cancer.展开更多
PbZrO_(3)-based antiferroelectric(AFE)ceramics are promising dielectrics for high-energy-density capacitors due to their reversible phase transitions during charge-discharge cycles.In this work,a new composition serie...PbZrO_(3)-based antiferroelectric(AFE)ceramics are promising dielectrics for high-energy-density capacitors due to their reversible phase transitions during charge-discharge cycles.In this work,a new composition series,[Pb_(0.93-x)La_(0.02)(Li_(1/2)Bi_(1/2))_(x)Sr_(0.04)][Zr_(0.57)Sn_(0.34)Ti_(0.09)]O_(3),with Li^(+)and Bi^(3+)substitution of Pb^(2+)at x=0,0.04,0.08,0.12,0.16 is investigated for the microstructure evolution,ferroelectric(FE)and dielectric properties.It is found that Li^(+) and Bi^(3+) substitution can significantly reduce the sintering temperature and simultaneously enhance the dielectric breakdown strength.An ultrahigh energy efficiency(94.0%)and a large energy density(3.22 J/cm^(3))are achieved in the composition of x=0.12 with a low sintering temperature(1075℃).展开更多
Electrical properties and the B-site cation order were investigated in the(1-x)Pb(Mg_(1/3)Nb_(2/3))O_(3)-xPbZrO_(3)(0≤x≤0.25)solid solution ceramics.It was found that long range 1.1 B-site cation order can be develo...Electrical properties and the B-site cation order were investigated in the(1-x)Pb(Mg_(1/3)Nb_(2/3))O_(3)-xPbZrO_(3)(0≤x≤0.25)solid solution ceramics.It was found that long range 1.1 B-site cation order can be developed through slow cooling during sintering in the solid solution with compositions around x=0.10.The observed long range cation order is in sharp contrast to previous studies where a disordered structure was invariably resulted in the(1-x)PbeMg_(1/3)Nb_(2/3)TO_(3)-xPbZrO_(3)solid solution.The ceramics with cation order display dielectric and ferroelectric properties similar to those disordered ceramics reported in literature.The dielectric properties were also compared in detail to our previous PbeMg_(1/3)Zr_(2x/3)Nb_(2)(1-x)/3TO_(3-x)/3 ceramics where Zr^(4+)is designed to substitute Nb^(5+)only.The results were discussed on the basis of the relationships between cation order and electric dipole order.展开更多
In this work,a CdS/BivO4 step-scheme(S-scheme)heterojunction with self-photothermally enhanced photocatalytic effect was synthesized and applied for efficient U(VI)photoextraction.Characterizations such as transient a...In this work,a CdS/BivO4 step-scheme(S-scheme)heterojunction with self-photothermally enhanced photocatalytic effect was synthesized and applied for efficient U(VI)photoextraction.Characterizations such as transient absorption spectroscopy and Tafel test together confirmed the formation of S-scheme heterojunctions,which allows CdS/BivO_(4) to avoid photocorrosion while retaining the strong reducing capacity of CdS and the oxidizing capacity of BivO_(4).Experimental results such as radical quenching experiments and electron spin resonance show that U(VI)is rapidly oxidized by photoholes/·OH to insoluble UO(OH)2 after being reduced to U(IV)by photoelectrons/·O2,which precisely avoids the depletion of electron sacrificial agents.The rapid recombination of electron-hole pairs triggered by the S-scheme heterojunction is found to release large amounts of heat and accelerate the photocatalysis.This work offers a new enhanced strategy for photocatalytic uranium extraction and presents a direction for the design and development of new photocatalysts.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.31771836)the National Key Research and Development Program of China(Grant No.2018YFD0201003).
文摘With the development of tourism at home and abroad,Rapeseed(Brassica napus)has become an important ornamental plant.However,its ornamental value at the inflorescence stage is greatly reduced by Sclerotinia sclerotiorum.Identification of important genes in the defense responses is critical for molecular breeding,which is an important strategy for controlling the disease.In this study,we isolated a B.napus WRKY transcription factor gene,BnaWRKY75.BnaWRKY75 was found to encode a nucleus-localized protein and exhibited relatively high expression in the stems.Arabidopsis thaliana transgenic plants expressing BnaWRKY75 showed enhanced resistance to S.sclerotiorum,and both ProBnaWRKY75:GUS and gene expression analyses showed that BnaWRKY75 was highly responsive to S.sclerotiorum infection,indicating the involvement of BnaWRKY75 in response to this infection.Furthermore,overexpression(OE)of BnaWRKY75 in B.napus significantly enhanced the resistance to S.sclerotiorum,whereas the resistance was reduced in RNAi transgenic B.napus plants.Moreover,the BnaWRKY75-OE B.napus plants exhibited constitutive activation of salicylic acid-,jasmonic acid-,and ethylene-mediated defense responses and the inhibition of both H_(2)O_(2)and O_(2)·^(-)accumulation in response to this pathogen.By contrast,BnaWRKY75-RNAi plants showed a reverse pattern,suggesting that BnaWRKY75 is involved in hormonal signaling pathways and in the control of reactive oxygen species accumulation.In conclusion,these data indicate that BnaWRKY75,a regulator of multiple defense responses,positively regulates resistance against S.sclerotiorum,which may guide the improvement of resistance in rapeseed.
基金supported by the National Natural Science Foundation of China(32201861)Ministry of Agriculture and Rural Affairs of China,the Key Research and Development Program of Jiangsu Province,China(BE2022383)the Zhongshan Biological Breeding Laboratory,China(ZSBBLKY2023-04-1)。
文摘Rice(Oryza sativa L.)is a globally important food crop.Its bran oil has high nutritional value,but with a low content of oleic acid and a high content of linoleic acid,which affects the stability and shelf life of the oil(Warner et al.2008;Liang et al.2017;Doureradjou and Koner 2020;Ghasemzadeh et al.2020).The fatty acid composition of rice bran oil is one of the healthiest edible oils due to its balanced source of saturated,monounsaturated,and polyunsaturated fatty acids with a ratio of 0.6:1.1:1(Liang et al.2017;Awad et al.2022).
基金financially supported by the National Postdoctoral Program for Innovative Talents, China (No. BX2021327)the National Natural Science Foundation of China (Nos. 22206194 and U2267222)+1 种基金the Ningbo Natural Science Foundation of China (No. 2023J337)the Yongjiang Talent Introduction Programme, China (No. 2 021A-161-G)。
文摘Herein, the electrochemical behaviors of Sr on inert W electrode and reactive Zn/Al electrodes were systematically investig-ated in LiCl–KCl–SrCl2molten salts at 773 K using various electrochemical methods. The chemical reaction potentials of Li and Sr on re-active Zn/Al electrodes were determined. We observed that Sr could be extracted by decreasing the activity of the deposited metal Sr onthe reactive electrode, although the standard reduction potential of Sr(II)/Sr was more negative than that of Li(I)/Li. The electrochemicalextraction products of Sr on reactive Zn and Al electrodes were Zn13Sr and Al4Sr, respectively, with no codeposition of Li observed.Based on the density functional theory calculations, both Zn13Sr and Al4Sr were identified as stable intermetallic compounds with Zn-/Al-rich phases. In LiCl–KCl molten salt containing 3wt% SrCl2, the coulombic efficiency of Sr in the Zn electrode was ~54%. The depolar-ization values for Sr on Zn and Al electrodes were 0.864 and 0.485 V, respectively, exhibiting a stronger chemical interaction between Znand Sr than between Al and Sr. This study suggests that using reactive electrodes can facilitate extraction of Sr accumulated while elec-trorefining molten salts, thereby enabling the purification and reuse of the salt and decreasing the volume of the nuclear waste.
基金This work was supported by the National Natural Science Foundation of China(NSFC 31571898,31772029,31572173).
文摘Ripening of the model fruit tomato(Solanum lycopersicum)is controlled by a transcription factor network including NAC(NAM,ATAF1/2,and CUC2)domain proteins such as No-ripening(NOR),SlNAC1,and SlNAC4,but very little is known about the NAC targets or how they regulate ripening.Here,we conducted a systematic search of fruit-expressed NAC genes and showed that silencing NOR-like1(Solyc07g063420)using virus-induced gene silencing(VIGS)inhibited specific aspects of ripening.Ripening initiation was delayed by 14 days when NOR-like1 function was inactivated by CRISPR/Cas9 and fruits showed obviously reduced ethylene production,retarded softening and chlorophyll loss,and reduced lycopene accumulation.RNA-sequencing profiling and gene promoter analysis suggested that genes involved in ethylene biosynthesis(SlACS2,SlACS4),color formation(SlGgpps2,SlSGR1),and cell wall metabolism(SlPG2a,SlPL,SlCEL2,and SlEXP1)are direct targets of NOR-like1.Electrophoretic mobility shift assays(EMSA),chromatin immunoprecipitation-quantitative PCR(ChIP-qPCR),and dual-luciferase reporter assay(DLR)confirmed that NOR-like1 bound to the promoters of these genes both in vitro and in vivo,and activated their expression.Our findings demonstrate that NOR-like1 is a new positive regulator of tomato fruit ripening,with an important role in the transcriptional regulatory network.
基金the financial support from Institute for Oil Sands Innovation(IOSI),Imperial Oil,the Natural Sciences and Engineering Research Council of Canada(NSERC)and Alberta Innovates to the research workthe financial support from the Canada Foundation for Innovation(CFI),the Future Energy Systems underthe Canada First Research Excellence Fund and the Canada Research Chairs Program。
文摘Non-aqueous extraction(NAE)of bitumen from oil sands has been gaining great attention from both the industry and academia as an alternative to the water-based extraction.A fine solids removal step is important for a NAE process in order to obtain high-quality bitumen product,which,however,remains a great challenge to reduce the fine solids content to the desired level.Here,we introduce a strategy of destabilizing the bitumen-coated silica particles in toluene with the addition of water and biomolecules extracted from Cyamopsiste tragonolobuosr L.Taup.,i.e.,high molecular weight guar gum(HGG)and low molecular weight guar gum(LGG),respectively.By virtue of sedimentation tests and focused beam reflectance measurement analysis,we demonstrate that the introduced water droplets modified with these biomolecules can facilitate the settling of the solid particles in toluene although the underlying mechanisms differ between these two biomolecule cases.Specifically,in the case of LGG,the added water droplets with the interfacial amphiphilic LGG can strengthen the attachment of solid particles from bulk toluene to the LGG surface.This research work provides useful insight into the development of effective approaches for destabilization and removal of bitumen-coated fine solids from NAE bitumen.
基金financially supported by the National High Technology Research and Development Program of China (No. 21677146)National Natural Science Foundation of China (Nos. 21876178, U1607102)the Anhui Provincial Natural Science Foundation (No. 1708085MB31)
文摘An acrylic modified pumpkin vine-based biochar(p-PVB-PAA) is synthesized by non-thermal plasma-grafting modification of pumpkin vine-based biochar(PVB) for the removal of uranyl from an aqueous solution. Microscopic characterization reveals that compared to PVB the surface of p-PVBPAA has more oxygen-containing functional groups by strong chemical bonding and the specific surface area is increased to 275.3 m^2 g^-1 from 3.8 m^2g^-1. It is found that p-PVB-PAA showed a much higher maximum adsorption capacity for uranyl from aqueous solutions than PVB, which were207.02 mg g^-1 and 67.58 mg g^-1 at pH=5 and 298 K, respectively. Moreover, the adsorption behavior follows a pseudo-second-order kinetics model and the Langmuir adsorption model.Additionally, macroscopic experiments and spectroscopic studies verified that the significantly improved adsorption performance of the p-PVB-PAA is due to surface complexation and electrostatic interactions. Furthermore, the very high removal efficiency and excellent regeneration ability(the percentage of the removal still remained at nearly 90% after five cycles) makes this low-cost, easily obtained, and environmentally friendly material attractive for commercial application.
基金the National Key Research and Development Program of China(2016YFD0100305,2016YFD0101900)。
文摘Brassica napus L(rapeseed)is one of the most important oil crops with large cultivated area in China.Seed size and seed weight play crucial roles for yield and harvest.In this study,a type of 15 bp-deletion in BnaGRF7.CO2 coding region was identified through sequence alignment of BnaGRF7.C02 in 42 rapeseed varieties,and associ-ation analysis indicated that the 15 bp-deletion was related to the rapeseed Thousand-Seed Weight(TSW)phenotype.Furthermore,we developed two InDel markers to identify this 15 bp InDel.The tissue-specific expression patterns showed that BnaGRF7.C02 prominently expressed in the late stage of seed development.These findings may assist in InDel markers-based breeding efforts to select higher TWS varieties and improve the crop yield of B.nqpus.
基金This work was supported by the National Natural Science Foundation of China(21976054,21976014,U1930402)the National Key Research and Development Program of China(2017YFA0207002)+1 种基金the Science Challenge Project(TZ2016004)the Fundamental Research Funds for the Central Universities(2020MS036).
文摘Extraction of uranium from radioactive waste-water is of significant importance for environmental protection and the recovery of uranium resource.Different from the previous reports to use the solid absorbent/photocatalyst for U(VI)removal,herein,we proposed a new eco-friendly method for the rapid and selective extraction of uranium from aqueous solutions under visible light without solid materials.At optimal pH value and in the presence of organics like alcohols,the U(VI)could be extracted efficiently to form brown uranium solid over wide uranium concentrations under anaerobic condition and visible light,by utilizing the excitation of the given U(VI)species.With comprehensive modelling of the electronic ultraviolet-visible(UV-Vis)properties,it is proved that pH adjusting towards U(VI)could induce efficient ligand-to-metal-charge-transfer(LMCT)within the uranyl complex under visible light and the reduction of U(VI)to form U(V),which can be transformed into U(IV)via disproportionation reaction.The resulting U(IV)in solid phase makes the extraction much more convenient in operation.More importantly,the excellent selectivity for uranium extraction over interfering alkali metal ions,transition metal ions and the lanthanide metal ions shows a powerful application potential.
基金the financial support by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF-2018R1D1A1B07051176)the financial support by the National Science Foundation(NSF)through Grant DMR-1700014the financial support from the ARC Discovery Project Scheme.
文摘Among the unresolved issues in the study of relaxor ferroelectrics is the role of freezing temperature,across which the dynamics of polarization reversal in relaxor ferroelectrics changes.The presence of this freezing temperature is best manifested by the appearance of a double polarization hysteresis loop just above the freezing temperature.Given that the polarization pinching evolving into a double hysteresis starts well below the freezing temperature,there exists a transient temperature regime between the nonergodic and the ergodic relaxor states.To clarify the role of the freezing temperature on the pinching,the polarization reversal near the freezing temperature of relaxor(Pb_(1-x)La_(x))(Zr_(1-y)T_(y))_(1-x/4)O_(3)(PLZT)was monitored using three in situ electric field methods:electrocaloric effect,neutron diffraction,and transmission electron microscopy.We demonstrate that the pinching results from a two-step process,1)domain detexturization in the ferroelectric state and 2)miniaturization of domains.This observation explains the recently reported gap between the depolarization temperature T_(d) and the ferroelectric-torelaxor transition temperature T_(F-R) in lead-free relaxors.We further show that T_(d) and T_(F-R),which have long been considered identical in lead-based relaxors,are not the same.The current study suggests that the mismatch between T_(d) and TF-R is an inherent feature in both lead-based and lead-free relaxor ferroelectrics.
基金the National Natural Science Foundation of China(21876047)the Thousand Talents Plan of Qinghai Province,the Basic Research Program of Qinghai Province(2021-ZJ-925)the Beijing Outstanding Young Scientist Program.
文摘Metal-enhanced photocatalysis has recently received increasing interest,mainly due to the ability of metal to directly or indirectly degrade pollutants.In this review,we briefly review the recent breakthroughs in metal-enhanced photocatalysis.We discussed the recent progress of surface plasmon resonance(SPR)effect and small size effect of metal nanoparticles on photocatalysis;in particular,we focus on elucidating the mechanism of energy transfer and hot electron injection/transfer effect of metal nanoparticles and clusters while as photocatalysts or as cophotocatalysts.Finally,we discuss the potential applications of metal-enhanced photocatalysis,and we also offer some perspectives for further investigations.
基金funded by the National Natural Science Foundation of China(Nos.22376060,U2267222,and U21A20290)Qinghai Provincial Science and Technology Project(No.2021-ZJ-925).
文摘The application of nanomaterials in energy and environmental fields has recently made great progress.As a key element in the nuclear industry,the discharge of uranium(U(VI))contained wastewater usually induces environmental issues and waste of resources.Although the catalytically generated H_(2)O_(2)by nanomaterials has recently shown application potential in extracting U(VI)from water,low-cost and highly efficient nanocatalysts are still urgently needed.In this work,a cheap and readily available piezocatalyst of calcium phosphate nanorods was successfully fabricated by calcining chicken bones.Under ultrasonication,H_(2)O_(2)was produced and used to extract U(VI)from water.It is worth noting that the yield of H_(2)O_(2)reached 179.7μmol·g^(−1)·h^(−1),and the extraction efficiency of U(VI)in water reached 97.16%(100 ppm)within 330 min.Through the capture and quantitative analysis of the active species,it is found that the generation of H_(2)O_(2)depends on the combination of soluble oxygen and piezoelectrons,which thus dominates the extraction of U(VI).This simple and powerful piezocatalytic strategy greatly reduces the cost of H_(2)O_(2)production for U(VI)extraction in water,and is of great significance for the treatment of U(VI)-containing wastewater.
基金supported by the National Natural Science Foundation of China[81971999 to X.F.]Science and Technology Achievements Transformation Project of Sun Yat-sen University[88000-18843232 to X.F.]+3 种基金Young Teacher Training Program of Sun Yat-sen University[14YKPY31 to X.F.]China Scholarship Council[201706385049 to X.F.]the program of Guangdong Provincial Clinical Research Center for Digestive Disease[2020B1111170004]National Key Clinical Discipline.
文摘Background:MLH1 promoter methylation analysis is recommended in screening for Lynch syndrome(LS)in patients with MLH1-deficient colorectal cancer(CRC).The study aims to identify specific methylation regions in the MLH1 promoter and to evaluate the clinicopathologic characteristics of and prognosis for patients with MLH1 methylation.Methods:A total of 580 CRC cases were included.The DNA mismatch repair(MMR)protein expression was assessed by using immunohistochemistry(IHC).The methylation status of the Regions A,B,C,D,and E in the MLH1 promoter was tested by using bisulfite sequencing PCR.The specificities of the five regions were calculated.Associations between MLH1 methylation and clinicopathologic characteristics were evaluated.Kaplan-Meier analyses for overall survival(OS)were carried out.Results:In 580 CRC cases,the specificities of the methylation test in Regions D and E were both 97.8%.In the MLH1-deficient CRCs,the frequencies of MLH1 methylation and BRAFV600E mutation were 52.6%and 14.6%,respectively;BRAFV600E mutation occurred in 27.7%of patients with MLH1-methylated CRC.In the MMR-deficient patients,compared with MLH1 unmethylation,MLH1 methylation was more common in patients who were aged≥50years,female,had no family history of LS-related tumors,and had tumors located at the right colon.In the MMR-deficient patients,the MLH1-methylated cases had lower OS rates than the unmethylated cases with a family history of LS-related tumors(P=0.047).Conclusions:Regions D and E in the MLH1 promoter are recommended for determining the MLH1 methylation status in screening for LS in MLH1-deficient CRC.In MMR-deficient patients,the MLH1-methylated cases had a worse OS than the unmethylated cases with a family history of LS-related cancer.
基金supported by the U.S.Department of Energy’s Office of Energy Efficiency and Renewable Energy(EERE)under the Advanced Manufacturing Office(AMO)Award Number DEEE0009105.
文摘PbZrO_(3)-based antiferroelectric(AFE)ceramics are promising dielectrics for high-energy-density capacitors due to their reversible phase transitions during charge-discharge cycles.In this work,a new composition series,[Pb_(0.93-x)La_(0.02)(Li_(1/2)Bi_(1/2))_(x)Sr_(0.04)][Zr_(0.57)Sn_(0.34)Ti_(0.09)]O_(3),with Li^(+)and Bi^(3+)substitution of Pb^(2+)at x=0,0.04,0.08,0.12,0.16 is investigated for the microstructure evolution,ferroelectric(FE)and dielectric properties.It is found that Li^(+) and Bi^(3+) substitution can significantly reduce the sintering temperature and simultaneously enhance the dielectric breakdown strength.An ultrahigh energy efficiency(94.0%)and a large energy density(3.22 J/cm^(3))are achieved in the composition of x=0.12 with a low sintering temperature(1075℃).
基金This work was supported by the National Science Foundation through the CAREER grant DMR-0346819.
文摘Electrical properties and the B-site cation order were investigated in the(1-x)Pb(Mg_(1/3)Nb_(2/3))O_(3)-xPbZrO_(3)(0≤x≤0.25)solid solution ceramics.It was found that long range 1.1 B-site cation order can be developed through slow cooling during sintering in the solid solution with compositions around x=0.10.The observed long range cation order is in sharp contrast to previous studies where a disordered structure was invariably resulted in the(1-x)PbeMg_(1/3)Nb_(2/3)TO_(3)-xPbZrO_(3)solid solution.The ceramics with cation order display dielectric and ferroelectric properties similar to those disordered ceramics reported in literature.The dielectric properties were also compared in detail to our previous PbeMg_(1/3)Zr_(2x/3)Nb_(2)(1-x)/3TO_(3-x)/3 ceramics where Zr^(4+)is designed to substitute Nb^(5+)only.The results were discussed on the basis of the relationships between cation order and electric dipole order.
基金funded by the National Key Research and Development Program of China(2018YFC1900105)National Natural Science Foundation of China(U21A20290,21876047)the Beijing Outstanding Young Scientist Program,and the Thousand Talents Plan of Qinghai province.
文摘In this work,a CdS/BivO4 step-scheme(S-scheme)heterojunction with self-photothermally enhanced photocatalytic effect was synthesized and applied for efficient U(VI)photoextraction.Characterizations such as transient absorption spectroscopy and Tafel test together confirmed the formation of S-scheme heterojunctions,which allows CdS/BivO_(4) to avoid photocorrosion while retaining the strong reducing capacity of CdS and the oxidizing capacity of BivO_(4).Experimental results such as radical quenching experiments and electron spin resonance show that U(VI)is rapidly oxidized by photoholes/·OH to insoluble UO(OH)2 after being reduced to U(IV)by photoelectrons/·O2,which precisely avoids the depletion of electron sacrificial agents.The rapid recombination of electron-hole pairs triggered by the S-scheme heterojunction is found to release large amounts of heat and accelerate the photocatalysis.This work offers a new enhanced strategy for photocatalytic uranium extraction and presents a direction for the design and development of new photocatalysts.
