Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinat...Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinations is more significant than a specific food component.This study investigated the lipid-lowering effect of highland barley polyphenols via lipase assay in vitro and HepG2 cells induced by oleic acid(OA).Five indexes,triglyceride(TG),total cholesterol(T-CHO),low density lipoprotein-cholesterol(LDL-C),aspartate aminotransferase(AST),and alanine aminotransferase(ALT),were used to evaluate the lipidlowering effect of highland barley extract.We also preliminary studied the lipid-lowering mechanism by Realtime fluorescent quantitative polymerase chain reaction(q PCR).The results indicated that highland barley extract contains many components with lipid-lowering effects,such as hyperoside and scoparone.In vitro,the lipase assay showed an 18.4%lipase inhibition rate when the additive contents of highland barley extract were 100μg/m L.The intracellular lipid-lowering effect of highland barley extract was examined using 0.25 mmol/L OA-induced HepG2 cells.The results showed that intracellular TG,LDL-C,and T-CHO content decreased by 34.4%,51.2%,and 18.4%,respectively.ALT and AST decreased by 51.6%and 20.7%compared with the untreated hyperlipidemic HepG2 cells.q PCR results showed that highland barley polyphenols could up-regulation the expression of lipid metabolism-related genes such as PPARγand Fabp4.展开更多
Verticillium wilt,caused by Verticillium dahliae,seriously restricts the yield and quality improvement of cotton.Previous studies have revealed the involvement of WRKY members in plant defense against V.dahliae,but th...Verticillium wilt,caused by Verticillium dahliae,seriously restricts the yield and quality improvement of cotton.Previous studies have revealed the involvement of WRKY members in plant defense against V.dahliae,but the underlying mechanisms involved need to be further elucidated.Here,we demonstrated that Gossypium hirsutum WRKY DNA-binding protein 33(GhWRKY33) functions as a negative regulator in plant defense against V.dahliae.GhWRKY33 expression is induced rapidly by V.dahliae and methyl jasmonate,and overexpression of GhWRKY33 reduces plant tolerance to V.dahliae in Arabidopsis.Quantitative RT-PCR analysis revealed that expression of several JA-associated genes was significantly repressed in GhWRKY33 overexpressing transgenic plants.Yeast one-hybrid analysis revealed that GhWRKY33 may repress the transcription of both AtERF1 and GhERF2 through its binding to their promoters.Protein-protein interaction analysis suggested that GhWRKY33 interacts with G.hirsutum JASMONATE ZIM-domain protein 3(GhJAZ3).Similarly,overexpression of GhJAZ3 also decreases plant tolerance to V.dahliae.Furthermore,GhJAZ3 acts synergistically with GhWRKY33 to suppress both AtERF1 and GhERF2 expression.Our results imply that GhWRKY33 may negatively regulate plant tolerance to V.dahliae via the JA-mediated signaling pathway.展开更多
This paper presents photoacoustic and ultrasonic dual-mode imaging for real-time detection of submucosal gastric cancer with a combination of gastroscopy.The diagnostic capacity was directly addressed via several phan...This paper presents photoacoustic and ultrasonic dual-mode imaging for real-time detection of submucosal gastric cancer with a combination of gastroscopy.The diagnostic capacity was directly addressed via several phantoms and ex vivo experiments.Results demonstrated that superficial and submucosal gastric cancer can be diagnosed with a perceptible depth of 6.33 mm,a lateral accuracy of 2.23 mm,and a longitudinal accuracy of 0.17 mm though capturing the morphology of angiogenesis,which is a main character of the therioma-related change.The capability of gastroscopy-conjugated photoacoustic and ultrasonic dual-mode imaging system will own great potential in improving the clinical diagnostic rate of submucosal gastric cancer.展开更多
Increasing evidence suggests that white matter disorders based on myelin sheath impairment may underlie the neuropathological changes in schizophrenia.But it is unknown whether enhancing remyelination is a beneficial ...Increasing evidence suggests that white matter disorders based on myelin sheath impairment may underlie the neuropathological changes in schizophrenia.But it is unknown whether enhancing remyelination is a beneficial approach to schizophrenia.To investigate this hypothesis,we used clemastine,an FDA-approved drug with high potency in promoting oligodendroglial differentiation and myelination,on a cuprizone-induced mouse model of demyelination.The mice exposed to cuprizone(0.2%in chow) for 6 weeks displayed schizophrenia-like behavioral changes,including decreased exploration of the center in the open field test and increased entries into the arms of the Y-maze,as well as evident demyelination in the cortex and corpus callosum.Clemastine treatment was initiated upon cuprizone withdrawal at 10 mg/kg per day for3 weeks.As expected,myelin repair was greatly enhanced in the demyelinated regions with increased mature oligodendrocytes(APC-positive) and myelin basic protein.More importantly,the clemastine treatment rescued the schizophrenia-like behavioral changes in the open field test and the Y-maze compared to vehicle,suggesting a beneficial effect via promoting myelin repair.Our findings indicate that enhancing remyelination may be a potential therapy for schizophrenia.展开更多
Many key cellular functions are regulated by the interplay of three distinct cytoskeletal networks, made of actin filaments,microtubules, and intermediate filaments(IFs), which is a hitherto poorly investigated area o...Many key cellular functions are regulated by the interplay of three distinct cytoskeletal networks, made of actin filaments,microtubules, and intermediate filaments(IFs), which is a hitherto poorly investigated area of research. However, there are growing evidence in the last few years showing that the IFs cooperate with actin filaments to exhibit strongly coupled functions.This review recapitulates our current knowledge on how the crosstalk between IFs and actin filaments modulates the migration properties, mechano-responsiveness and signaling transduction of cells, from both biophysical and biochemical point of view.展开更多
CuCe/CNT_(x)-SAPO-34(x=0,0.5,1,2) with various CNT doping quantities were synthesized through the one-pot hydrothermal synthesis method using CNT and SAPO-34 as composite supporters.The selected CuCe/CNT_1-SAPO-34 cat...CuCe/CNT_(x)-SAPO-34(x=0,0.5,1,2) with various CNT doping quantities were synthesized through the one-pot hydrothermal synthesis method using CNT and SAPO-34 as composite supporters.The selected CuCe/CNT_1-SAPO-34 catalyst exhibits remarkable SCR activity and high H_(2)O/SO_(2) resistance in a wide temperature range of 200-450℃.X-ray diffraction(XRD),N_(2) adsorption-desorption,scanning electron microscopy(SEM),X-ray photoelectro n spectroscopy(XPS),H_(2)-temperature programmed reduction(H2-TPR),and NH3-temperature programmed desorption(NH_(3)-TPD) were used to characterize the physiochemical structure,surface state of active sites reducibility,and surface acidity of the catalysts.The characterization results reveal that CuCe/CNT_1-SAPO-34 possesses a hierarchical structure,small particle size,high levels of surface Cu^(2+),Ce^(3+) and chemisorbed oxygen,enhanced reducibility,and suitable surface acidity.For comparison,CuCe/CNT_1-SAPO-34(P) mixed mechanically with CuCe/CNT_0-SAPO-34and CNT was investigated through the NH3-SCR with and without H_(2)O/SO_(2),it also displays lower resistance of H_(2)O and SO_(2) than CuCe/CNT_1-SAPO-34.The catalytic performance made CuCe/CNT_1-SAPO-34 a promising catalyst for the NO_(x) emission control from diesel vehicles.展开更多
Approximately 140 million people worldwide are homozygous carriers of APOE4(ε4),a strong genetic risk factor for late onset familial and sporadic Alzheimer’s disease(AD),91%of whom will develop AD at earlier age tha...Approximately 140 million people worldwide are homozygous carriers of APOE4(ε4),a strong genetic risk factor for late onset familial and sporadic Alzheimer’s disease(AD),91%of whom will develop AD at earlier age than heterozygous carriers and noncarriers.Susceptibility to AD could be reduced by targeted editing of APOE4,but a technical basis for controlling the off-target effects of base editors is necessary to develop low-risk personalized gene therapies.Here,we first screened eight cytosine base editor variants at four injection stages(from 1-to 8-cell stage),and found that FNLS-YE1 variant in 8-cell embryos achieved the comparable base conversion rate(up to 100%)with the lowest bystander effects.In particular,80%of AD-susceptibleε4 allele copies were converted to the AD-neutralε3 allele in humanε4-carrying embryos.Stringent control measures combined with targeted deep sequencing,whole genome sequencing,and RNA sequencing showed no DNA or RNA off-target events in FNLS-YE1-treated human embryos or their derived stem cells.Furthermore,base editing with FNLS-YE1 showed no effects on embryo development to the blastocyst stage.Finally,we also demonstrated FNLS-YE1 could introduce known protective variants in human embryos to potentially reduce human susceptivity to systemic lupus erythematosus and familial hypercholesterolemia.Our study therefore suggests that base editing with FNLS-YE1 can efficiently and safely introduce known preventive variants in 8-cell human embryos,a potential approach for reducing human susceptibility to AD or other genetic diseases.展开更多
The effects of La on the catalytic performance,SO_(2)and H2O resistance of Cu-Ce/TNU-9 catalyst were studied in the selective catalytic reduction of NO_(x)via ammonia(NH_(3)-SCR).The results show that the La doped Ce-...The effects of La on the catalytic performance,SO_(2)and H2O resistance of Cu-Ce/TNU-9 catalyst were studied in the selective catalytic reduction of NO_(x)via ammonia(NH_(3)-SCR).The results show that the La doped Ce-Cu/TNU-9(CCL/T9)catalyst exhibits better SCR performance than Ce-Cu/TNU-9(CC/T9)and Cu/TNU-9(C/T9)in the wide temperature window(200-450℃)due to La benefiting from enhancing Cu^(+)+Ce^(4+)?Cu^(2+)-+Ce^(3+)to facilitate the electron transfer,which further accelerates the oxidation of NO into NO_(2)that leads to the"Fast SCR".The La can also enhance the surface acidic,redox property and is beneficial to the formation of oxygen vacancy.Meanwhile,the larger co ntent of Ce^(3+) can produce oxygen vacancy,resulting in rising SCR activity.The CCL/T9 has outstanding water and SO_(2) resistance,which may be due to the adso rbed S on the surface of these catalysts mainly existing in the form of a small amount of sulfate and sulfite,the decomposition of ammonium bisulphite under high temperature and the hydrophobicity of TNU-9 zeolite.展开更多
SAPO-34,SAPO-5/34 based catalysts doped with Cu,Ce as active components were synthesized via a one-pot hydrothermal method by using different amounts of additive(a-cellulose),and their catalytic activities were measur...SAPO-34,SAPO-5/34 based catalysts doped with Cu,Ce as active components were synthesized via a one-pot hydrothermal method by using different amounts of additive(a-cellulose),and their catalytic activities were measured for selective catalytic reduction(SCR) of NO with NH3.The synthesized Cu-Ce co-doped products switch from cubic SAPO-34,to flower-like aggregated SAPO-5/34,hybrid crystal SAPO-5/34,and finally to spherical aggregated SAPO-34 with the increase of α-cellulose amount.The Cu-Ce co-doped SAPO-5/34 hybrid crystal structure catalysts with 0.75 mol ratios of C/P(Cu-Ce/SP-0.75)exhibit excellent NH_(3)-SCR activity with higher than 90% NOx conversion in the temperature range of 180-450℃,at WHSV of 20000 mL/(g·h).Furthermore,the catalyst displays outstanding sulfur resistance and NOX conversion maintains above 90% at 200-450℃ after adding 100 ppm of SO_(2).The characteristic results suggest that the high deNOX performance of Cu-Ce/SP-0.75 is due to the enhanced accessibility,abundant activity species,excellent redox property and high adsorptive and activated capacity for NH_(3).展开更多
A novel and simple fluorescence probe was synthesized from benzo[l,2-b：4,5-b＇]dithiophene （BDT） and trime-thylsilylethyne via Sonogashira reaction, and showed highly selective and sensitive fluorescence decreasing...A novel and simple fluorescence probe was synthesized from benzo[l,2-b：4,5-b＇]dithiophene （BDT） and trime-thylsilylethyne via Sonogashira reaction, and showed highly selective and sensitive fluorescence decreasing re-sponse towards F . The probe molecule turned to a weakly fluorescent terminal alkyne moiety because its trime-thylsilyl （TMS） group was cleaved by fluoride, which was proved by IH NMR titration. Whereas no distinct fluo-rescent changes were observed with the addition of other anions, such as C1^-, B^_r, I^-, AcO^- and HzPO4 . Upon theaddition of F-, the maximum fluorescence emission wavelength shifted from 460 nm to 450 nm with a decrease offluorescence intensity by 40% within 20 s. Moreover, the detection limit towards F- was calculated to be as low as73.5 nmol/L.展开更多
Two copolymers,poly(1,1-dimethyl-3,4-diphenylsilole-alt-N-hexyl-3,6-diethynylcarbazole)(PS-DyCz)and poly-(1,1-dimethyl-3,4-diphenylsilole-alt-2,7-diethynyl-9,9'-dihexylfluorene)(PS-DyF),were synthesized by Sonogas...Two copolymers,poly(1,1-dimethyl-3,4-diphenylsilole-alt-N-hexyl-3,6-diethynylcarbazole)(PS-DyCz)and poly-(1,1-dimethyl-3,4-diphenylsilole-alt-2,7-diethynyl-9,9'-dihexylfluorene)(PS-DyF),were synthesized by Sonogashira coupling reaction of 2,5-dibromo-1,1-dimethyl-3,4-diphenylsilole and N-hexyl-3,6-diethynylcarbazole or 2,7-diethynyl-9,9'-dihexylfluorene,respectively.The chemical structures of the copolymers were characterized by NMR,FT-IR techniques.Their thermal and photophysical properties were evaluated by TGA,DSC,UV-Vis and fluorescence spectroscopy,respectively.The weight-averaged molecular weights(Mw)of PS-DyCz and PS-DyF are 1.20×10^(4) and 3.83×10^(4) Da,respectively.The degree of polymerization is 8 and 22 units.Theseπ-conjugated polymers exhibited lower band-gap of 2.25 and 2.70 eV due to the presence of silole rings and C≡C triple bonds in their backbone,the results were consistent with the density functional(DFT)calculations at the B3LYP/6-31G^(*)level.展开更多
基金financially supported by the National Key Research and Development Program of China(2021YFD2100904)the National Natural Science Foundation of China(31871729,32172147)+2 种基金the Modern Agriculture key Project of Jiangsu Province of China(BE2022317)the Modern Agricultural Industrial Technology System Construction Project of Jiangsu Province of China(JATS[2021]522)a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinations is more significant than a specific food component.This study investigated the lipid-lowering effect of highland barley polyphenols via lipase assay in vitro and HepG2 cells induced by oleic acid(OA).Five indexes,triglyceride(TG),total cholesterol(T-CHO),low density lipoprotein-cholesterol(LDL-C),aspartate aminotransferase(AST),and alanine aminotransferase(ALT),were used to evaluate the lipidlowering effect of highland barley extract.We also preliminary studied the lipid-lowering mechanism by Realtime fluorescent quantitative polymerase chain reaction(q PCR).The results indicated that highland barley extract contains many components with lipid-lowering effects,such as hyperoside and scoparone.In vitro,the lipase assay showed an 18.4%lipase inhibition rate when the additive contents of highland barley extract were 100μg/m L.The intracellular lipid-lowering effect of highland barley extract was examined using 0.25 mmol/L OA-induced HepG2 cells.The results showed that intracellular TG,LDL-C,and T-CHO content decreased by 34.4%,51.2%,and 18.4%,respectively.ALT and AST decreased by 51.6%and 20.7%compared with the untreated hyperlipidemic HepG2 cells.q PCR results showed that highland barley polyphenols could up-regulation the expression of lipid metabolism-related genes such as PPARγand Fabp4.
基金This work was supported by the National key R&D plan(2016YFD0101006)Yunnan Fundamental Research Projects(2019FA010).
文摘Verticillium wilt,caused by Verticillium dahliae,seriously restricts the yield and quality improvement of cotton.Previous studies have revealed the involvement of WRKY members in plant defense against V.dahliae,but the underlying mechanisms involved need to be further elucidated.Here,we demonstrated that Gossypium hirsutum WRKY DNA-binding protein 33(GhWRKY33) functions as a negative regulator in plant defense against V.dahliae.GhWRKY33 expression is induced rapidly by V.dahliae and methyl jasmonate,and overexpression of GhWRKY33 reduces plant tolerance to V.dahliae in Arabidopsis.Quantitative RT-PCR analysis revealed that expression of several JA-associated genes was significantly repressed in GhWRKY33 overexpressing transgenic plants.Yeast one-hybrid analysis revealed that GhWRKY33 may repress the transcription of both AtERF1 and GhERF2 through its binding to their promoters.Protein-protein interaction analysis suggested that GhWRKY33 interacts with G.hirsutum JASMONATE ZIM-domain protein 3(GhJAZ3).Similarly,overexpression of GhJAZ3 also decreases plant tolerance to V.dahliae.Furthermore,GhJAZ3 acts synergistically with GhWRKY33 to suppress both AtERF1 and GhERF2 expression.Our results imply that GhWRKY33 may negatively regulate plant tolerance to V.dahliae via the JA-mediated signaling pathway.
基金National Natural Science Foundation of China(Grant Nos.61675043,81571726,and 81901787)the Natural Science Foundation of Fujian Province,China(Grant Nos.2018J01785 and 2018J01659).
文摘This paper presents photoacoustic and ultrasonic dual-mode imaging for real-time detection of submucosal gastric cancer with a combination of gastroscopy.The diagnostic capacity was directly addressed via several phantoms and ex vivo experiments.Results demonstrated that superficial and submucosal gastric cancer can be diagnosed with a perceptible depth of 6.33 mm,a lateral accuracy of 2.23 mm,and a longitudinal accuracy of 0.17 mm though capturing the morphology of angiogenesis,which is a main character of the therioma-related change.The capability of gastroscopy-conjugated photoacoustic and ultrasonic dual-mode imaging system will own great potential in improving the clinical diagnostic rate of submucosal gastric cancer.
基金supported by the National Natural Science Foundation of China ( 81100897 and 81100926 )the Natural Science Foundation of Chongqing Municipality, China (cstc2011jj A0856)
文摘Increasing evidence suggests that white matter disorders based on myelin sheath impairment may underlie the neuropathological changes in schizophrenia.But it is unknown whether enhancing remyelination is a beneficial approach to schizophrenia.To investigate this hypothesis,we used clemastine,an FDA-approved drug with high potency in promoting oligodendroglial differentiation and myelination,on a cuprizone-induced mouse model of demyelination.The mice exposed to cuprizone(0.2%in chow) for 6 weeks displayed schizophrenia-like behavioral changes,including decreased exploration of the center in the open field test and increased entries into the arms of the Y-maze,as well as evident demyelination in the cortex and corpus callosum.Clemastine treatment was initiated upon cuprizone withdrawal at 10 mg/kg per day for3 weeks.As expected,myelin repair was greatly enhanced in the demyelinated regions with increased mature oligodendrocytes(APC-positive) and myelin basic protein.More importantly,the clemastine treatment rescued the schizophrenia-like behavioral changes in the open field test and the Y-maze compared to vehicle,suggesting a beneficial effect via promoting myelin repair.Our findings indicate that enhancing remyelination may be a potential therapy for schizophrenia.
基金supported by Collaborative Research Grant (KLMVI-OP-201904) of CAS Key Laboratory of Molecular Virology & Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciencesthe starting grant of Institut Pasteur of Shanghai (1185170000), Chinese Academy of Sciences
文摘Many key cellular functions are regulated by the interplay of three distinct cytoskeletal networks, made of actin filaments,microtubules, and intermediate filaments(IFs), which is a hitherto poorly investigated area of research. However, there are growing evidence in the last few years showing that the IFs cooperate with actin filaments to exhibit strongly coupled functions.This review recapitulates our current knowledge on how the crosstalk between IFs and actin filaments modulates the migration properties, mechano-responsiveness and signaling transduction of cells, from both biophysical and biochemical point of view.
基金This work was supported by the National Natural Science Foundation of China （Nos. 21202031, 21472032） and Zhejiang Provincial Natural Science Foundation of China （No. Y4110297）.
基金supported by the Basic Science Research Project of Heilongjiang Provincial University,China (145109109)。
文摘CuCe/CNT_(x)-SAPO-34(x=0,0.5,1,2) with various CNT doping quantities were synthesized through the one-pot hydrothermal synthesis method using CNT and SAPO-34 as composite supporters.The selected CuCe/CNT_1-SAPO-34 catalyst exhibits remarkable SCR activity and high H_(2)O/SO_(2) resistance in a wide temperature range of 200-450℃.X-ray diffraction(XRD),N_(2) adsorption-desorption,scanning electron microscopy(SEM),X-ray photoelectro n spectroscopy(XPS),H_(2)-temperature programmed reduction(H2-TPR),and NH3-temperature programmed desorption(NH_(3)-TPD) were used to characterize the physiochemical structure,surface state of active sites reducibility,and surface acidity of the catalysts.The characterization results reveal that CuCe/CNT_1-SAPO-34 possesses a hierarchical structure,small particle size,high levels of surface Cu^(2+),Ce^(3+) and chemisorbed oxygen,enhanced reducibility,and suitable surface acidity.For comparison,CuCe/CNT_1-SAPO-34(P) mixed mechanically with CuCe/CNT_0-SAPO-34and CNT was investigated through the NH3-SCR with and without H_(2)O/SO_(2),it also displays lower resistance of H_(2)O and SO_(2) than CuCe/CNT_1-SAPO-34.The catalytic performance made CuCe/CNT_1-SAPO-34 a promising catalyst for the NO_(x) emission control from diesel vehicles.
基金supported by Chinese National Science and Technology major project R&D Program of China(2018YFC2000101)Strategic Priority Research Program of Chinese Academy of Science(XDB32060000)+7 种基金National Natural Science Foundation of China(Grant Nos.31871502,31901047,31925016,91957122,82021001,and 31922048)Basic Frontier Scientific Research Program of Chinese Academy of Sciences From 0 to 1 original innovation project(ZDBS-LYSM001)Shanghai Municipal Science and Technology Major Project(2018SHZDZX05)Shanghai City Committee of Science and Technology Project(18411953700,18JC1410100,19XD1424400 and 19YF1455100)Innovative Research Team of High-Level Local Universities in Shanghai(SHSMU-ZDCX20212200 and SHSMU-ZLCX20210200)International Partnership Program of Chinese Academy of Sciences(153D31KYSB20170059)Postdoctoral Science Foundation of China(2020M681417 and 2021T140684)Sailing Program of Shanghai(21YF1453000)(to J.H.).
文摘Approximately 140 million people worldwide are homozygous carriers of APOE4(ε4),a strong genetic risk factor for late onset familial and sporadic Alzheimer’s disease(AD),91%of whom will develop AD at earlier age than heterozygous carriers and noncarriers.Susceptibility to AD could be reduced by targeted editing of APOE4,but a technical basis for controlling the off-target effects of base editors is necessary to develop low-risk personalized gene therapies.Here,we first screened eight cytosine base editor variants at four injection stages(from 1-to 8-cell stage),and found that FNLS-YE1 variant in 8-cell embryos achieved the comparable base conversion rate(up to 100%)with the lowest bystander effects.In particular,80%of AD-susceptibleε4 allele copies were converted to the AD-neutralε3 allele in humanε4-carrying embryos.Stringent control measures combined with targeted deep sequencing,whole genome sequencing,and RNA sequencing showed no DNA or RNA off-target events in FNLS-YE1-treated human embryos or their derived stem cells.Furthermore,base editing with FNLS-YE1 showed no effects on embryo development to the blastocyst stage.Finally,we also demonstrated FNLS-YE1 could introduce known protective variants in human embryos to potentially reduce human susceptivity to systemic lupus erythematosus and familial hypercholesterolemia.Our study therefore suggests that base editing with FNLS-YE1 can efficiently and safely introduce known preventive variants in 8-cell human embryos,a potential approach for reducing human susceptibility to AD or other genetic diseases.
基金supported by the National Natural Science Foundation of China(51708309)the Fundamental Research Funds in Heilongjiang Provincial Universities(145109115)。
文摘The effects of La on the catalytic performance,SO_(2)and H2O resistance of Cu-Ce/TNU-9 catalyst were studied in the selective catalytic reduction of NO_(x)via ammonia(NH_(3)-SCR).The results show that the La doped Ce-Cu/TNU-9(CCL/T9)catalyst exhibits better SCR performance than Ce-Cu/TNU-9(CC/T9)and Cu/TNU-9(C/T9)in the wide temperature window(200-450℃)due to La benefiting from enhancing Cu^(+)+Ce^(4+)?Cu^(2+)-+Ce^(3+)to facilitate the electron transfer,which further accelerates the oxidation of NO into NO_(2)that leads to the"Fast SCR".The La can also enhance the surface acidic,redox property and is beneficial to the formation of oxygen vacancy.Meanwhile,the larger co ntent of Ce^(3+) can produce oxygen vacancy,resulting in rising SCR activity.The CCL/T9 has outstanding water and SO_(2) resistance,which may be due to the adso rbed S on the surface of these catalysts mainly existing in the form of a small amount of sulfate and sulfite,the decomposition of ammonium bisulphite under high temperature and the hydrophobicity of TNU-9 zeolite.
基金supported by the National Natural Science Foundation of China (51708309)Natural Science Foundation of Heilongjiang Province+1 种基金China (QC2017065)the University Nursing Program for Young Scholars with Creative Talents in Heilongjiang Province (UNPYSCT-2018106)。
文摘SAPO-34,SAPO-5/34 based catalysts doped with Cu,Ce as active components were synthesized via a one-pot hydrothermal method by using different amounts of additive(a-cellulose),and their catalytic activities were measured for selective catalytic reduction(SCR) of NO with NH3.The synthesized Cu-Ce co-doped products switch from cubic SAPO-34,to flower-like aggregated SAPO-5/34,hybrid crystal SAPO-5/34,and finally to spherical aggregated SAPO-34 with the increase of α-cellulose amount.The Cu-Ce co-doped SAPO-5/34 hybrid crystal structure catalysts with 0.75 mol ratios of C/P(Cu-Ce/SP-0.75)exhibit excellent NH_(3)-SCR activity with higher than 90% NOx conversion in the temperature range of 180-450℃,at WHSV of 20000 mL/(g·h).Furthermore,the catalyst displays outstanding sulfur resistance and NOX conversion maintains above 90% at 200-450℃ after adding 100 ppm of SO_(2).The characteristic results suggest that the high deNOX performance of Cu-Ce/SP-0.75 is due to the enhanced accessibility,abundant activity species,excellent redox property and high adsorptive and activated capacity for NH_(3).
文摘A novel and simple fluorescence probe was synthesized from benzo[l,2-b：4,5-b＇]dithiophene （BDT） and trime-thylsilylethyne via Sonogashira reaction, and showed highly selective and sensitive fluorescence decreasing re-sponse towards F . The probe molecule turned to a weakly fluorescent terminal alkyne moiety because its trime-thylsilyl （TMS） group was cleaved by fluoride, which was proved by IH NMR titration. Whereas no distinct fluo-rescent changes were observed with the addition of other anions, such as C1^-, B^_r, I^-, AcO^- and HzPO4 . Upon theaddition of F-, the maximum fluorescence emission wavelength shifted from 460 nm to 450 nm with a decrease offluorescence intensity by 40% within 20 s. Moreover, the detection limit towards F- was calculated to be as low as73.5 nmol/L.
基金the financial support from the National Natural Science Foundation of China(Nos.20872035,21076078),and the Hangzhou Normal University.
文摘Two copolymers,poly(1,1-dimethyl-3,4-diphenylsilole-alt-N-hexyl-3,6-diethynylcarbazole)(PS-DyCz)and poly-(1,1-dimethyl-3,4-diphenylsilole-alt-2,7-diethynyl-9,9'-dihexylfluorene)(PS-DyF),were synthesized by Sonogashira coupling reaction of 2,5-dibromo-1,1-dimethyl-3,4-diphenylsilole and N-hexyl-3,6-diethynylcarbazole or 2,7-diethynyl-9,9'-dihexylfluorene,respectively.The chemical structures of the copolymers were characterized by NMR,FT-IR techniques.Their thermal and photophysical properties were evaluated by TGA,DSC,UV-Vis and fluorescence spectroscopy,respectively.The weight-averaged molecular weights(Mw)of PS-DyCz and PS-DyF are 1.20×10^(4) and 3.83×10^(4) Da,respectively.The degree of polymerization is 8 and 22 units.Theseπ-conjugated polymers exhibited lower band-gap of 2.25 and 2.70 eV due to the presence of silole rings and C≡C triple bonds in their backbone,the results were consistent with the density functional(DFT)calculations at the B3LYP/6-31G^(*)level.
