INTRODUCTIONThe main component of a traditional Chinese drug 'Pishuang'. arsenic trioxide (As2O3), has obviously selective anti-tumor effect on human hepatocellular carcinoma (HCC)in both in vitro and in vivo ...INTRODUCTIONThe main component of a traditional Chinese drug 'Pishuang'. arsenic trioxide (As2O3), has obviously selective anti-tumor effect on human hepatocellular carcinoma (HCC)in both in vitro and in vivo studies[1-5]. Due to limited effectiveness when any anti-carcinogen is used alone and obviously increased toxicity when the dose is raised, there is no exception for As2O3. Furthermore, combined chemotherapy contributes to improve therapeutic effectiveness, disperse toxicity and surmount drug-resistance,in which the combination of traditional Chinese and modern medicine has more advantages and characteristics. As a result,we made an experimental study on anti-tumor effect of As2O3in combination with cisplantin (PDD) or doxorubicin (ADM)on HCC. to investigate the possibility of AS2O3 in combination with PDD or ADM and nature of interaction between them,and to provide experimental basis for clinical application.展开更多
OBJECTIVE: To investigate the response of multiple myeloma (MM) cells to arsenic trioxide (As2O3) and their possible mechanisms. METHODS: Two MM-derived cell lines RPMI8226 and U266 cells were used as in vitro models....OBJECTIVE: To investigate the response of multiple myeloma (MM) cells to arsenic trioxide (As2O3) and their possible mechanisms. METHODS: Two MM-derived cell lines RPMI8226 and U266 cells were used as in vitro models. Cell apoptosis was assessed by morphology, flow cytometry, and DNA gel electrophoresis. Mitochondrial transmembrane potentials (delta psi m) were evaluated by measuring cellular Rhodamine 123 staining intensity. Protein expression was analyzed using Western blot. RESULTS: Zero point one to 0.5 mumol/L As2O3 inhibited cell proliferation and 2.0 mumol/L As2O3 induced cell apoptosis, while 1.0 mumol/L As2O3 inhibited proliferation with a weak degree of apoptosis induction in RPMI8226 and U266 cell lines. As2O3-induced apoptosis was accompanied by mitochondrial transmembrane potentials (delta psi m) collapse and caspase-3 activation in the presence of intact membrane. Glutathione depleter buthionine sulfoximine enhanced, while disulfide bond-reducing agent dithiothreitol partially antagonized As2O3-induced delta psi m collapse and apoptosis in MM cells. All-trans retinoic acid (ATRA) could also induce apoptosis in RPMI8226 cells, but it did not show any cooperative effects with As2O3. CONCLUSION: As2O3 exerts apoptosis-inducing and growth-inhibiting effects on MM cells, and mitochondrium is a pivotal and common target of As2O3 for apoptosis induction.展开更多
This work examines the influence of preparation methods on the physicochemical properties and catalytic performance of MnOx‐CeO2 catalysts for selective catalytic reduction of NO by NH3 (NH3‐SCR) at low temperature....This work examines the influence of preparation methods on the physicochemical properties and catalytic performance of MnOx‐CeO2 catalysts for selective catalytic reduction of NO by NH3 (NH3‐SCR) at low temperature. Five different methods, namely, mechanical mixing, impregnation,hydrothermal treatment, co‐precipitation, and a sol‐gel technique, were used to synthesizeMnOx‐CeO2 catalysts. The catalysts were characterized in detail, and an NH3‐SCR model reaction waschosen to evaluate the catalytic performance. The results showed that the preparation methodsaffected the catalytic performance in the order: hydrothermal treatment > sol‐gel > co‐precipitation> impregnation > mechanical mixing. This order correlated with the surface Ce3+ and Mn4+ content,oxygen vacancies and surface adsorbed oxygen species concentration, and the amount of acidic sitesand acidic strength. This trend is related to redox interactions between MnOx and CeO2. The catalystformed by a hydrothermal treatment exhibited excellent physicochemical properties, optimal catalyticperformance, and good H2O resistance in NH3‐SCR reaction. This was attributed to incorporationof Mnn+ into the CeO2 lattice to form a uniform ceria‐based solid solution (containing Mn‐O‐Cestructures). Strengthening of the electronic interactions between MnOx and CeO2, driven by thehigh‐temperature and high‐pressure conditions during the hydrothermal treatment also improved the catalyst characteristics. Thus, the hydrothermal treatment method is an efficient and environment‐friendly route to synthesizing low‐temperature denitrification (deNOx) catalysts.展开更多
The water stability of aggregates in various size classes separated from 18 samples of red soils under different managements, and the mechanisms responsible for the formation of water-stable soil aggregates were studi...The water stability of aggregates in various size classes separated from 18 samples of red soils under different managements, and the mechanisms responsible for the formation of water-stable soil aggregates were studied. The results showed that the water stability of soil aggregates declined with increasing size, especially for the low organic matter soils. Organic matter plays a key role in the formation of water-stable soil aggregates. The larger the soil aggregate size, the greater the impact of organic matter on the water stability of soil aggregates. Removal of organic matter markedly disintegrated the large water-stable aggregates (> 2.0 mm) and increased the small ones (< 0.25-0.smm) to some extent, whereas removal of free iron(aluminium) oxides considerably destroyed aggregates of all sizes, especially the < 0.25-0.5 mm classes. The contents of organic matter in water-stable aggregates increased with aggregate sizes. It is concluded from this study that small water-stable aggregates (< 0.25-0.5 mm) were chiefly cemented by Fe and Al oxides whilst the large ones (> 2.0 mm) were mainly glued up by organic matter. Both free oxides and organic matter contribute to the formation and water stability of aggregates in red soils.展开更多
A monolithic series of Cu-Mn-Ce oxides supported on cordierites with different Cu/Mn/Ce molar ratios were prepared by the in-situ sol-gel method without any binder. The catalysts were characterized by scanning electro...A monolithic series of Cu-Mn-Ce oxides supported on cordierites with different Cu/Mn/Ce molar ratios were prepared by the in-situ sol-gel method without any binder. The catalysts were characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD), and Brunauer-Emmett-Teller method (BET) and examined in the catalytic combustion of volatile organic compounds (VOCs). The results showed that the well-dispersed nanometer particles of mixed oxides adhered firmly to the cordierite surface. Cu0.15Mn0.3Ce55/cordierite was identified as the most active catalyst. Compared with commercial Pd/Al2O3, Cu0.15Mn0.3Ce55/cordierite showed higher activities for the combustion of various types of VOCs, especially for oxy-derivative compounds which could be lighted off below 200 ℃.展开更多
Li-ion batteries(LIBs)with excellent cycling stability and high-energy densities have already occupied the commercial rechargeable battery market.Unfortunately,the high cost and intrinsic insecurity induced by organic...Li-ion batteries(LIBs)with excellent cycling stability and high-energy densities have already occupied the commercial rechargeable battery market.Unfortunately,the high cost and intrinsic insecurity induced by organic electrolyte severely hinder their applications in large-scale energy storage.In contrast,aqueous Zn-ion batteries(ZIBs)are being developed as an ideal candidate because of their cheapness and high security.Benefiting from high operating voltage and acceptable specific capacity,recently,manganese-based oxides with different various crystal structures have been extensively studied as cathode materials for aqueous ZIBs.This review presents research progress of manganese-based cathodes in aqueous ZIBs,including various manganese-based oxides and their zinc storage mechanisms.In addition,we also discuss some optimization strategies that aim at improving the electrochemical performance of manganese-based cathodes,and the design of flexible aqueous ZIBs based on manganese-based cathodes(MZIBs).Finally,this review summarizes some valuable research directions,which will promote the further development of aqueous MZIBs.展开更多
Hierarchical layer-stacking Mn-Ce composite oxide with mesoporous structure was firstly prepared by a simple precipitation/decomposition procedure with oxalate precursor and the complete catalytic oxidation of VOCs(b...Hierarchical layer-stacking Mn-Ce composite oxide with mesoporous structure was firstly prepared by a simple precipitation/decomposition procedure with oxalate precursor and the complete catalytic oxidation of VOCs(benzene, toluene and ethyl acetate) were examined. The Mn-Ce oxalate precursor was obtained from metal salt and oxalic acid without any additives. The resulting materials were characterized by X-ray diffraction(XRD), Brunauer-Emmett-Teller(BET), scanning electron microscopy(SEM), energy dispersive X-ray spectroscopy(EDX), hydrogen temperature programmed reduction(H2-TPR) and X-ray photoelectron spectroscopy(XPS). Compared with Mn-Ce composite oxide synthesized through a traditional method(Na2CO3 route), the hierarchical layer-stacking Mn-Ce composite oxide exhibited higher catalytic activity in the complete oxidation of volatile organic compounds(VOCs). By means of testing, the data revealed that the hierarchical layer-stacking Mn-Ce composite oxide possessed superior physiochemical properties such as good low-temperature reducibility, high manganese oxidation state and rich adsorbed surface oxygen species which resulted in the enhancement of catalytic abilities.展开更多
基金Supported by the Youth Science Grant of Jiangshu Province,No.BQ98048.
文摘INTRODUCTIONThe main component of a traditional Chinese drug 'Pishuang'. arsenic trioxide (As2O3), has obviously selective anti-tumor effect on human hepatocellular carcinoma (HCC)in both in vitro and in vivo studies[1-5]. Due to limited effectiveness when any anti-carcinogen is used alone and obviously increased toxicity when the dose is raised, there is no exception for As2O3. Furthermore, combined chemotherapy contributes to improve therapeutic effectiveness, disperse toxicity and surmount drug-resistance,in which the combination of traditional Chinese and modern medicine has more advantages and characteristics. As a result,we made an experimental study on anti-tumor effect of As2O3in combination with cisplantin (PDD) or doxorubicin (ADM)on HCC. to investigate the possibility of AS2O3 in combination with PDD or ADM and nature of interaction between them,and to provide experimental basis for clinical application.
基金theNationalNaturalScienceFoundationofChina (No 39970 312andNo 39730 2 70 ) NationalOutstandingYoungScientificFoundationofC
文摘OBJECTIVE: To investigate the response of multiple myeloma (MM) cells to arsenic trioxide (As2O3) and their possible mechanisms. METHODS: Two MM-derived cell lines RPMI8226 and U266 cells were used as in vitro models. Cell apoptosis was assessed by morphology, flow cytometry, and DNA gel electrophoresis. Mitochondrial transmembrane potentials (delta psi m) were evaluated by measuring cellular Rhodamine 123 staining intensity. Protein expression was analyzed using Western blot. RESULTS: Zero point one to 0.5 mumol/L As2O3 inhibited cell proliferation and 2.0 mumol/L As2O3 induced cell apoptosis, while 1.0 mumol/L As2O3 inhibited proliferation with a weak degree of apoptosis induction in RPMI8226 and U266 cell lines. As2O3-induced apoptosis was accompanied by mitochondrial transmembrane potentials (delta psi m) collapse and caspase-3 activation in the presence of intact membrane. Glutathione depleter buthionine sulfoximine enhanced, while disulfide bond-reducing agent dithiothreitol partially antagonized As2O3-induced delta psi m collapse and apoptosis in MM cells. All-trans retinoic acid (ATRA) could also induce apoptosis in RPMI8226 cells, but it did not show any cooperative effects with As2O3. CONCLUSION: As2O3 exerts apoptosis-inducing and growth-inhibiting effects on MM cells, and mitochondrium is a pivotal and common target of As2O3 for apoptosis induction.
基金supported by the National Natural Science Foundation of China (No. 21507130)the Open Project Program of Beijing National Laboratory for Molecular Sciences (No. 20140142)+3 种基金the Open Project Program of Chongqing Key Laboratory of Environmental Materials and Remediation Technology from Chongqing University of Arts and Sciences (No. CEK1405)the Open Project Program of Jiangsu Key Laboratory of Vehicle Emissions Control (No. OVEC001)the Open Project Program of Chongqing Key Laboratory of Catalysis and Functional Organic Molecules from Chongqing Technology and Business University (1456029)the Chongqing Science & Technology Commission (Nos. cstc2016jcyj A0070, cstc2014pt-gc20002, cstckjcxljrc13)~~
文摘This work examines the influence of preparation methods on the physicochemical properties and catalytic performance of MnOx‐CeO2 catalysts for selective catalytic reduction of NO by NH3 (NH3‐SCR) at low temperature. Five different methods, namely, mechanical mixing, impregnation,hydrothermal treatment, co‐precipitation, and a sol‐gel technique, were used to synthesizeMnOx‐CeO2 catalysts. The catalysts were characterized in detail, and an NH3‐SCR model reaction waschosen to evaluate the catalytic performance. The results showed that the preparation methodsaffected the catalytic performance in the order: hydrothermal treatment > sol‐gel > co‐precipitation> impregnation > mechanical mixing. This order correlated with the surface Ce3+ and Mn4+ content,oxygen vacancies and surface adsorbed oxygen species concentration, and the amount of acidic sitesand acidic strength. This trend is related to redox interactions between MnOx and CeO2. The catalystformed by a hydrothermal treatment exhibited excellent physicochemical properties, optimal catalyticperformance, and good H2O resistance in NH3‐SCR reaction. This was attributed to incorporationof Mnn+ into the CeO2 lattice to form a uniform ceria‐based solid solution (containing Mn‐O‐Cestructures). Strengthening of the electronic interactions between MnOx and CeO2, driven by thehigh‐temperature and high‐pressure conditions during the hydrothermal treatment also improved the catalyst characteristics. Thus, the hydrothermal treatment method is an efficient and environment‐friendly route to synthesizing low‐temperature denitrification (deNOx) catalysts.
文摘The water stability of aggregates in various size classes separated from 18 samples of red soils under different managements, and the mechanisms responsible for the formation of water-stable soil aggregates were studied. The results showed that the water stability of soil aggregates declined with increasing size, especially for the low organic matter soils. Organic matter plays a key role in the formation of water-stable soil aggregates. The larger the soil aggregate size, the greater the impact of organic matter on the water stability of soil aggregates. Removal of organic matter markedly disintegrated the large water-stable aggregates (> 2.0 mm) and increased the small ones (< 0.25-0.smm) to some extent, whereas removal of free iron(aluminium) oxides considerably destroyed aggregates of all sizes, especially the < 0.25-0.5 mm classes. The contents of organic matter in water-stable aggregates increased with aggregate sizes. It is concluded from this study that small water-stable aggregates (< 0.25-0.5 mm) were chiefly cemented by Fe and Al oxides whilst the large ones (> 2.0 mm) were mainly glued up by organic matter. Both free oxides and organic matter contribute to the formation and water stability of aggregates in red soils.
基金Project supported by National Natural Science Foundation of China (21107096)Zhejiang Provincial Natural Science Foundation (Y5090202)
文摘A monolithic series of Cu-Mn-Ce oxides supported on cordierites with different Cu/Mn/Ce molar ratios were prepared by the in-situ sol-gel method without any binder. The catalysts were characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD), and Brunauer-Emmett-Teller method (BET) and examined in the catalytic combustion of volatile organic compounds (VOCs). The results showed that the well-dispersed nanometer particles of mixed oxides adhered firmly to the cordierite surface. Cu0.15Mn0.3Ce55/cordierite was identified as the most active catalyst. Compared with commercial Pd/Al2O3, Cu0.15Mn0.3Ce55/cordierite showed higher activities for the combustion of various types of VOCs, especially for oxy-derivative compounds which could be lighted off below 200 ℃.
基金This work was financially supported by This work was financially supported by the National Natural Science Foundation of China(21725103 and 51631004)National Key R&D Program of China(2016YFB0100103,2017YFA0206704)+2 种基金People's Government of Jilin Province Science and Technology Development Plan Funding Project(20180101203JC)Changchun Science and Technology Development Plan Funding Project(18DY012,19SS010)the Program for the JLU Science and Technology Innovative Research Team(2017TD-09).
文摘Li-ion batteries(LIBs)with excellent cycling stability and high-energy densities have already occupied the commercial rechargeable battery market.Unfortunately,the high cost and intrinsic insecurity induced by organic electrolyte severely hinder their applications in large-scale energy storage.In contrast,aqueous Zn-ion batteries(ZIBs)are being developed as an ideal candidate because of their cheapness and high security.Benefiting from high operating voltage and acceptable specific capacity,recently,manganese-based oxides with different various crystal structures have been extensively studied as cathode materials for aqueous ZIBs.This review presents research progress of manganese-based cathodes in aqueous ZIBs,including various manganese-based oxides and their zinc storage mechanisms.In addition,we also discuss some optimization strategies that aim at improving the electrochemical performance of manganese-based cathodes,and the design of flexible aqueous ZIBs based on manganese-based cathodes(MZIBs).Finally,this review summarizes some valuable research directions,which will promote the further development of aqueous MZIBs.
基金supported by Strategic Project of Science and Technology of Chinese Academy of Sciences(XDB05050000)the National Natural Science Foundation of China(51272253)
文摘Hierarchical layer-stacking Mn-Ce composite oxide with mesoporous structure was firstly prepared by a simple precipitation/decomposition procedure with oxalate precursor and the complete catalytic oxidation of VOCs(benzene, toluene and ethyl acetate) were examined. The Mn-Ce oxalate precursor was obtained from metal salt and oxalic acid without any additives. The resulting materials were characterized by X-ray diffraction(XRD), Brunauer-Emmett-Teller(BET), scanning electron microscopy(SEM), energy dispersive X-ray spectroscopy(EDX), hydrogen temperature programmed reduction(H2-TPR) and X-ray photoelectron spectroscopy(XPS). Compared with Mn-Ce composite oxide synthesized through a traditional method(Na2CO3 route), the hierarchical layer-stacking Mn-Ce composite oxide exhibited higher catalytic activity in the complete oxidation of volatile organic compounds(VOCs). By means of testing, the data revealed that the hierarchical layer-stacking Mn-Ce composite oxide possessed superior physiochemical properties such as good low-temperature reducibility, high manganese oxidation state and rich adsorbed surface oxygen species which resulted in the enhancement of catalytic abilities.