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现代技术与人的“物”化
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作者 殷正坤 《哲学研究》 CSSCI 北大核心 2001年第12期19-20,共2页
关键词 现代技术 “物”化 生存哲学 工业革命 生存方式 信息时代 生命科学
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从生物化学的角度看担子菌子实体形成 被引量:3
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作者 北本丰 辻山彰一 《食用菌学报》 CSCD 北大核心 2015年第4期9-12,共4页
总结了从生物化学的角度看待担子菌子实体形成的研究进展。通过以金针菇为模型的RI示踪实验,解析了菌丝体中积蓄的糖原作为营养成长过程中的主要贮藏碳水化合物、随着子实体形成的开始而被分解、被转换为海藻糖后输送到子实体、并作为... 总结了从生物化学的角度看待担子菌子实体形成的研究进展。通过以金针菇为模型的RI示踪实验,解析了菌丝体中积蓄的糖原作为营养成长过程中的主要贮藏碳水化合物、随着子实体形成的开始而被分解、被转换为海藻糖后输送到子实体、并作为主要发育基质被利用。笔者率先发现了存在于海藻糖的合成与分解代谢中的新酶—海藻糖磷酸化酶(TP),接着,在几种食用菌的生化反应中证明了此酶存在并通过基因克隆方法发现此酶在子实体形成中的作用—在营养菌丝体中以糖原为基质催化加磷酸反应,形成α-G1P海藻糖,当海藻糖输送到子实体,借助该酶的加磷酸分解功能生成α-G1P葡萄糖,而葡萄糖作为子实体发育中的主要糖代谢基质而被加以利用。了解了营养菌丝从培养基中吸收的葡萄糖基本上不能从菌丝体输送到子实体。通过基因实验,检证了TP在营养菌丝体中对催化海藻糖的合成作用。另一方面,该酶还具有加磷酸分解从菌丝体输送到子实体的海藻糖的生理功能,伴随子实体发育的细胞内磷酸糖类分析证明了α-G1P(α-1磷酸葡萄糖)的含量比α-G6P(α-6磷酸葡萄糖)更多。另外,从子实体形成过程中氮化合物代谢分析表明,营养菌丝的菌体蛋白为形成子实体的主要氮素来源,当生殖生长启动时被菌丝体内的蛋白酶分解,形成的氨基酸输送到子实体并被用于子实体发育。通过这些研究的累积,已大致了解了碳素和氮素在子实体形成过程中的动态,但是,从营养生长转换到子实体形成的机制却至今仍不明了。 展开更多
关键词 代谢调控 子实体形成 输送碳水 贮藏碳水 蛋白质水解
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分散固相萃取-气相色谱-串联质谱法测定动物源性食品中9种N-亚硝胺类化合物 被引量:22
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作者 赵博 邓美林 +3 位作者 杨小珊 段云鹏 吴晓琴 屠大伟 《色谱》 CAS CSCD 北大核心 2016年第10期998-1004,共7页
建立了分散固相萃取-同位素稀释-气相色谱-串联质谱同时测定动物源性食品中9种况-亚硝胺的方法.样品用乙腈提取,上清液经分散固相萃取(dSPE)净化后浓缩.选用DB-WAX极性毛细管色谱柱对待测物进行分离,经EI源电离后以多反应监测(MRM)... 建立了分散固相萃取-同位素稀释-气相色谱-串联质谱同时测定动物源性食品中9种况-亚硝胺的方法.样品用乙腈提取,上清液经分散固相萃取(dSPE)净化后浓缩.选用DB-WAX极性毛细管色谱柱对待测物进行分离,经EI源电离后以多反应监测(MRM)模式采集数据并做定性筛查和定量分析.9种况-亚硝胺在相应的浓度范围内线性关系良好,相关系数均大于0.99,对4类典型的动物源性食品进行3个不同浓度的加标试验,平均回收率为62.5%-118%,只80为2.11%-25.6%,检出限([00,5/况=3)为0.02-0.31μg/kg.该方法成本低廉、灵敏可靠,适用于同时对动物源性食品中9种况-亚硝胺进行定性和定量测定. 展开更多
关键词 分散固相萃取 同位素稀释 气相色谱-串联质谱 N-亚硝胺 源性食品
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《结构化学》简介
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作者 《结构化学》编辑部 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第4期716-716,共1页
《结构化学》是由中国科学院主管,中国化学会、中国科学院福建物质结构研究所主办的学术性期刊。1982年由我国著名化学家卢嘉锡院士创办并担任主编,现任主编是著名化学家吴新涛院士。《结构化学》主要报道晶体学,量子化学,药物、材料和... 《结构化学》是由中国科学院主管,中国化学会、中国科学院福建物质结构研究所主办的学术性期刊。1982年由我国著名化学家卢嘉锡院士创办并担任主编,现任主编是著名化学家吴新涛院士。《结构化学》主要报道晶体学,量子化学,药物、材料和催化剂等领域物质性能与结构关系的文章。报道的内容涉及有机化学、无机化学、合成化学、结构化学、材料科学、药物化学、晶体学、理论化学等学科中的微观物质结构与性能关系的研究成果或阶段性成果。与此同时本刊也报道用谱学等物理方法解析物质结构、阐述物质结构与性能关系的论文。 展开更多
关键词 结构 质结构研究 卢嘉锡 中国学会 中国科学院 量子 吴新
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『竹取物語』と『斑竹姑娘』の比較研究
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作者 郑玲 《科技信息》 2013年第6期232-232,235,共2页
『竹取物語』は「物語の出で来はじめの祖」と『源氏物語』総合卷に記されているように、日本で現存する最古の物語文学である。その求婚難題の部分は中国四川省のアバ.チベット族に伝わる『斑竹姑娘』という物語に酷似しているため、... 『竹取物語』は「物語の出で来はじめの祖」と『源氏物語』総合卷に記されているように、日本で現存する最古の物語文学である。その求婚難題の部分は中国四川省のアバ.チベット族に伝わる『斑竹姑娘』という物語に酷似しているため、本稿は両物語の異同点を分析することにより、両者の主題と中日文化の異同点について検討しようと思う。 展开更多
关键词 竹取 斑竹姑娘 異同 比較
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Growing Development and Physiological Characteristics of Seeds Harvested Different Days after Pollination and Their 7-day Seedlings of Two Yellow-Seeded Cultivars of Brassica napus L.
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作者 GAO You-li ZHANG Long-yan +5 位作者 KANG Lei CHEN Xing-ke ZOU Ke WANG Xiang-juan ZHANG Wei TANG Shan-shan 《Agricultural Science & Technology》 CAS 2024年第3期6-13,共8页
This study aimed to understand the growing development and physiological characteristics of seeds harvested different days after pollination and the seedlings emerged from the seeds of yellow-seeded Brassica napus L..... This study aimed to understand the growing development and physiological characteristics of seeds harvested different days after pollination and the seedlings emerged from the seeds of yellow-seeded Brassica napus L..Two yellow-seeded cultivars‘Hongyuan 558’and‘Qinyou 806’were selected in this study,and 50 seeds were collected 30,35,and 40 d after pollination,respectively.The seeds were weighed and placed on filter paper for hydroponic experiments.The seed germination rate was determined 3-5 d later.The physiological indicators including superoxide dismutase(SOD),peroxidase(POD),and catalase(CAT)activities and malondialdehyde(MDA)content were measured for the seeds harvested different days after pollination and the 7-day-seedlings emerged from the seeds.The results showed that the seed dry weights and germination rates of both‘Qinyou 806’and‘Hongyuan 558’increased as the days after pollination increased,especially 30-35 d after pollination.The germination rate and dry and fresh weights of the seeds showed no significant differences between the two cultivars,and almost all the seeds germinated 40 d after pollination.As the days after pollination increased,the SOD activities in the seeds of both cultivars first increased and then decreased,reaching their peaks 35 d after pollination,which may be related to encountering adverse stress.The POD activity in the seeds of‘Qinyou 806’kept declining,and that of‘Hongyuan 558’first increased and then decreased,which may be related to the antioxidant mechanism and adaptive regulation.The CAT activities in the seeds of both cultivars first decreased and then increased.The MDA content in the seeds of‘Qinyou 806’first decreased and then increased,while that of‘Hongyuan 558’kept reducing and was the highest in the seeds 30 d after pollination,which indicated‘Hongyuan 558’was mildly affected by the environment and had strong resistance.The activities of SOD and POD in the seedlings of two cultivars that were emerged from the seeds 35-40 d after pollination became weakened,which may be related to their exposure to stress.The CAT activity in the seedlings of‘Hongyuan 558’was generally higher than that of‘Qinyou 806’,indicating that‘Hongyuan 558’had stronger stress resistance.The MDA content in the seedlings emerged from the seeds 35-40 d after pollination showed a decreasing trend,indicating that the seedlings emerged from the seeds harvested at this stage had mild cell membrane damage and enhanced stress resistance.In conclusion,‘Hongyuan 558’had strong environmental adaptability and stress resistance. 展开更多
关键词 Yellow-seeded Brassica napus Superoxide dismutase PEROXIDASE CATALASE MALONDIALDEHYDE
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Graphene-loaded nickel−vanadium bimetal oxides as hydrogen pumps to boost solid-state hydrogen storage kinetic performance of magnesium hydride
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作者 Dong-qiang GAO Fu-ying WU +4 位作者 Zhi ZHANG Zi-chuan LU Ren ZHOU Hu ZHAO Liu-ting ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2645-2657,共13页
To modify the thermodynamics and kinetic performance of magnesium hydride(MgH_(2))for solid-state hydrogen storage,Ni_(3)V_(2)O_(8)-rGO(rGO represents reduced graphene oxide)and Ni_(3)V_(2)O_(8)nanocomposites were pre... To modify the thermodynamics and kinetic performance of magnesium hydride(MgH_(2))for solid-state hydrogen storage,Ni_(3)V_(2)O_(8)-rGO(rGO represents reduced graphene oxide)and Ni_(3)V_(2)O_(8)nanocomposites were prepared by hydrothermal and subsequent heat treatment.The beginning hydrogen desorption temperature of 7 wt.%Ni_(3)V_(2)O_(8)-rGO modified MgH_(2)was reduced to 208℃,while the additive-free MgH_(2)and 7 wt.%Ni_(3)V_(2)O_(8)doped MgH_(2)appeared to discharge hydrogen at 340 and 226℃,respectively.A charging capacity of about 4.7 wt.%H_(2)for MgH_(2)+7 wt.%Ni_(3)V_(2)O_(8)-rGO was achieved at 125℃ in 10 min,while the dehydrogenated MgH_(2)took 60 min to absorb only 4.6 wt.%H_(2)at 215℃.The microstructure analysis confirmed that the in-situ generated Mg_(2)Ni/Mg_(2)N_(i)H_(4) and metallic V contributed significantly to the enhanced performance of MgH_(2).In addition,the presence of rGO in the MgH_(2)+7 wt.%Ni_(3)V_(2)O_(8)-rGO composite reduced particle aggregation tendency of Mg/MgH_(2),leading to improving the cyclic stability of MgH_(2)during 20 cycles. 展开更多
关键词 hydrogen storage properties MgH_(2) graphene-loaded Ni−V bimetal oxides catalytic mechanism
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Effect of Elastic Strains on Adsorption Energies of C,H and O on Transition Metal Oxides
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作者 XIE Tian SONG Erhong 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2024年第11期1292-1302,共11页
Platinum(Pt)-based noble metal catalysts(PGMs)are the most widely used commercial catalysts,but they have the problems of high cost,low reserves,and susceptibility to small-molecule toxicity.Transition metal oxides(TM... Platinum(Pt)-based noble metal catalysts(PGMs)are the most widely used commercial catalysts,but they have the problems of high cost,low reserves,and susceptibility to small-molecule toxicity.Transition metal oxides(TMOs)are regarded as potential substitutes for PGMs because of their stability in oxidizing environments and excellent catalytic performance.In this study,comprehensive investigation into the influence of elastic strains on the adsorption energies of carbon(C),hydrogen(H)and oxygen(O)on TMOs was conducted.Based on density functional theory(DFT)calculations,these effects in both tetragonal structures(PtO_(2),PdO_(2))and hexagonal structures(ZnO,CdO),along with their respective transition metals were systematically explored.It was identified that the optimal adsorption sites on metal oxides pinpointed the top of oxygen or the top of metal atom,while face-centered cubic(FCC)and hexagonal close-packed(HCP)holes were preferred for the transition metals.Furthermore,under the influence of elastic strains,the results demonstrated significant disparities in the adsorption energies of H and O between oxides and transition metals.Despite these differences,the effect of elastic strains on the adsorption energies of C,H and O on TMOs mirrored those on transition metals:adsorption energies increased under compressive strains,indicating weaker adsorption,and decreased under tension strains,indicating stronger adsorption.This behavior was rationalized based on the d-band model for adsorption atop a metallic atom or the p-band model for adsorption atop an oxygen atom.Consequently,elastic strains present a promising avenue for tailoring the catalytic properties of TMOs. 展开更多
关键词 density functional theory adsorption energy elastic strain engineering transition metal oxide CATALYST
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Freestanding oxide membranes:synthesis,tunable physical properties,and functional devices
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作者 Ao Wang Jinfeng Zhang Lingfei Wang 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第7期2-17,1,I0002,共18页
The study of oxide heteroepitaxy has been hindered by the issues of misfit strain and substrate clamping,which impede both the optimization of performance and the acquisition of a fundamental understanding of oxide sy... The study of oxide heteroepitaxy has been hindered by the issues of misfit strain and substrate clamping,which impede both the optimization of performance and the acquisition of a fundamental understanding of oxide systems.Recently,however,the development of freestanding oxide membranes has provided a plausible solution to these substrate limitations.Single-crystalline functional oxide films can be released from their substrates without incurring significant damage and can subsequently be transferred to any substrate of choice.This paper discusses recent advancements in the fabrication,adjustable physical properties,and various applications of freestanding oxide perovskite films.First,we present the primary strategies employed for the synthesis and transfer of these freestanding perovskite thin films.Second,we explore the main functionalities observed in freestanding perovskite oxide thin films,with special attention to the tunable functionalities and physical properties of these freestanding perovskite membranes under varying strain states.Next,we encapsulate three representative devices based on freestanding oxide films.Overall,this review highlights the potential of freestanding oxide films for the study of novel functionalities and flexible electronics. 展开更多
关键词 freestanding oxide membranes transition metal oxides thin films electronic devices
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Electro‑copolymerized film of ruthenium catalyst and redox mediator for electrocatalytic water oxidation
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作者 WANG Hao TANG Kun +2 位作者 SHAO Jiangyang WANG Kezhi ZHONG Yuwu 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第11期2193-2202,共10页
Electro-copolymerized film containing ruthenium complexes as electron-transfer(or redox)mediators and water-oxidation catalysts by an oxidative copolymerization method is presented.The addition of the redox mediator s... Electro-copolymerized film containing ruthenium complexes as electron-transfer(or redox)mediators and water-oxidation catalysts by an oxidative copolymerization method is presented.The addition of the redox mediator significantly improved the electrocatalytic water-oxidation activity and reduced the overpotential to 220 mV.The prepared electrode showed a water-oxidation catalytic rate constant kobs of 31.7 s^(-1)and an initial turnover frequency of 1.01 s^(-1)in 1000 s by potential electrolysis at 1.7 V applied bias vs NHE(normal hydrogen electrode).The kinetic isotope effect study suggests that the catalytic water oxidation reaction on the electrode surface occurs via a bimolecular coupling mechanism. 展开更多
关键词 water oxidation water splitting ruthenium complexes ELECTROPOLYMERIZATION ELECTROCATALYSIS
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Understanding the roles of Brønsted/Lewis acid sites on manganese oxide-zeolite hybrid catalysts for low-temperature NH_(3)-SCR
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作者 Hyun Sub Kim Hwangho Lee +2 位作者 Hongbeom Park Inhak Song Do Heui Kim 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第10期79-88,共10页
Although metal oxide-zeolite hybrid materials have long been known to achieve enhanced catalytic activity and selectivity in NO_(x)removal reactions through the inter-particle diffusion of intermediate species,their s... Although metal oxide-zeolite hybrid materials have long been known to achieve enhanced catalytic activity and selectivity in NO_(x)removal reactions through the inter-particle diffusion of intermediate species,their subsequent reaction mechanism on acid sites is still unclear and requires investigation.In this study,the distribution of Brønsted/Lewis acid sites in the hybrid materials was precisely adjusted by introducing potassium ions,which not only selectively bind to Brønsted acid sites but also potentially affect the formation and diffusion of activated NO species.Systematic in situ diffuse reflectance infrared Fourier transform spectroscopy analyses coupled with selective catalytic reduction of NO_(x)with NH_(3)(NH_(3)-SCR)reaction demonstrate that the Lewis acid sites over MnO_(x)are more active for NO reduction but have lower selectivity to N_(2)than Brønsted acids sites.Brønsted acid sites primarily produce N_(2),whereas Lewis acid sites primarily produce N_(2)O,contributing to unfavorable N_(2)selectivity.The Brønsted acid sites present in Y zeolite,which are stronger than those on MnO_(x),accelerate the NH_(3)-SCR reaction in which the nitrite/nitrate species diffused from the MnO_(x)particles rapidly convert into the N_(2).Therefore,it is important to design the catalyst so that the activated NO species formed in MnO_(x)diffuse to and are selectively decomposed on the Brønsted acid sites of H-Y zeolite rather than that of MnO_(x)particle.For the physically mixed H-MnO_(x)+H-Y sample,the abundant Brønsted/Lewis acid sites in H-MnO_(x)give rise to significant consumption of activated NO species before their inter-particle diffusion,thereby hindering the enhancement of the synergistic effects.Furthermore,we found that the intercalated K+in K-MnO_(x)has an unexpected favorable role in the NO reduction rate,probably owing to faster diffusion of the activated NO species on K-MnO_(x)than H-MnO_(x).This study will help to design promising metal oxide-zeolite hybrid catalysts by identifying the role of the acid sites in two different constituents. 展开更多
关键词 Hybrid metal oxide-zeolite The role of acid sites Manganese oxides Physical mixing Selective catalytic reduction of NOx with NH3
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Conjugated microporous polymers-scaffolded enzyme cascade systems with enhanced catalytic activity
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作者 Zhenhua Wu Jiafu Shi +6 位作者 Boyu Zhang Yushuai Jiao Xiangxuan Meng Ziyi Chu Yu Chen Yiran Cheng Zhongyi Jiang 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期213-223,共11页
Enhancing catalytic activity of multi-enzyme in vitro through substrate channeling effect is promis-ing yet challenging.Herein,conjugated microporous polymers(CMPs)-scaffolded integrated en-zyme cascade systems(I-ECSs... Enhancing catalytic activity of multi-enzyme in vitro through substrate channeling effect is promis-ing yet challenging.Herein,conjugated microporous polymers(CMPs)-scaffolded integrated en-zyme cascade systems(I-ECSs)are constructed through co-entrapping glucose oxidase(GOx)and horseradish peroxidase(HRP),in which hydrogen peroxide(H_(2)O_(2)) is the intermediate product.The interplay of low-resistance mass transfer pathway and appropriate pore wall-H_(2)O_(2) interactions facilitates the directed transfer of H_(2)O_(2),resulting in 2.4-fold and 5.0-fold elevation in catalytic activ-ity compared to free ECSs and separated ECSs,respectively.The substrate channeling effect could be regulated by altering the mass ratio of GOx to HRP.Besides,I-ECSs demonstrate excellent stabili-ties in harsh environments and multiple recycling. 展开更多
关键词 BIOCATALYSIS IMMOBILIZATION Enzyme cascade system Substrate channeling effect Conjugated microporous polymers
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Single atom doping induced charge-specific distribution of Cu1-TiO_(2) for selective aniline oxidation via a new mechanism
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作者 Jiaheng Qin Wantong Zhao +6 位作者 Jie Song Nan Luo Zheng-Lan Ma Baojun Wang Jiantai Ma Riguang Zhang Yu Long 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第9期98-111,共14页
Utilizing single atom sites doping into metal oxides to modulate their intrinsic active sites,achieving precise selectivity control in complex organic reactions,is a highly desirable yet challenging endeavor.Meanwhile... Utilizing single atom sites doping into metal oxides to modulate their intrinsic active sites,achieving precise selectivity control in complex organic reactions,is a highly desirable yet challenging endeavor.Meanwhile,identifying the active site also represents a significant obstacle,primarily due to the intricate electronic environment of single atom site doped metal oxide.Herein,a single atom Cu doped TiO_(2)catalyst(Cu_(1)-TiO_(2)) is prepared via a simple“colloid-acid treatment”strategy,which switches aniline oxidation selectivity of TiO_(2) from azoxybenzene to nitrosobenzene,without using additives or changing solvent,while other metal or nonmetal doped TiO_(2) did not possess.Comprehensive mechanistic investigations and DFT calculations unveil that Ti-O active site is responsible for triggering the aniline to form a new PhNOH intermediate,two PhNOH condense to azoxybenzene over TiO_(2) catalyst.As for Cu_(1)-TiO_(2),the charge-specific distribution between the isolated Cu and TiO_(2) generates unique Cu_(1)-O-Ti hybridization structure with nine catalytic active sites,eight of them make PhNOH take place spontaneous dissociation to produce nitrosobenzene.This work not only unveils a new mechanistic pathway featuring the PhNOH intermediate in aniline oxidation for the first time but also presents a novel approach for constructing single-atom doped metal oxides and exploring their intricate active sites. 展开更多
关键词 Single atom doped metal oxide Aniline oxidation Selectivity New mechanism Active site
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Process Optimization of Cu-en/AP Composite Microspheres Preparation by Electrostatic Spray Method Based on ANSYS Simulation
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作者 LIU Lei HU Tian-yuan +1 位作者 SONG Ming-jun JI Wei 《火炸药学报》 EI CAS CSCD 北大核心 2024年第10期899-909,I0002,共12页
To investigate the process optimizationof Cu-en/AP composite microspheres preparation via electrostatic spraying,and to reveal the effects of droplet properties and flow rate variations on the experimental results dur... To investigate the process optimizationof Cu-en/AP composite microspheres preparation via electrostatic spraying,and to reveal the effects of droplet properties and flow rate variations on the experimental results during the electrostatic spraying process,the prepared process parameters of Cu-en/AP composite microspheres by electrostatic spray method under the orthogonal experimental design simulated by ANSYS(Fluent).The influence of flow rate,solvent ratio,and solid mass on the experimental results is examined using a controlled variable method.The results indicate that under the conditions of a flow rate of 2.67×10^(-3)kg/s an acetone-to-deionized water ratio of 1.5∶1.0,and a solid mass of 200 mg,the theoretical particle size of the composite microspheres can reach e nanoscale.Droplet trajectories in the electric field remain stable without significant deviation.The simulation results show that particle diameter decreases with increasing flow rate,with the trend leveling off around a flow rate of 1×10^(-3)kg/s.As the solvent ratio increases(with higher acetone content),particle diameter initially decreases,reaching a minimum around a ratio of 1.5∶1.0 before gradually increasing.Increasing the solid mass also reduces the particle diameter,with a linear increase in diameter observed at around 220 mg.Cu-en/AP composite microspheres with nanoscale dimensions were confirmed under these conditions by the final SEM images. 展开更多
关键词 physical chemistry fluent simulation ammonium perchlorate composite microspheres electrostatic spray process conditions
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Chalcogenide-based S-scheme heterojunction photocatalysts
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作者 Chunguang Chen Jinfeng Zhang +3 位作者 Hailiang Chu Lixian Sun Graham Dawson Kai Dai 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期81-108,共28页
The unique photocatalytic mechanism of S-scheme heterojunction can be used to study new and efficient photocatalysts.By carefully selecting semiconductors for S-scheme heterojunction photocatalysts,it is possible to r... The unique photocatalytic mechanism of S-scheme heterojunction can be used to study new and efficient photocatalysts.By carefully selecting semiconductors for S-scheme heterojunction photocatalysts,it is possible to reduce the rate of photogenerated carrier recombination and increase the conversion efficiency of light into energy.Chalcogenides are a group of compounds that include sulfides and selenides(e.g.,CdS,ZnS,Bi_(2)S_(3),MoS_(2),ZnSe,CdSe,and CuSe).Chalcogenides have attracted considerable attention as heterojunction photocatalysts owing to their narrow bandgap,wide light absorption range,and excellent photoreduction properties.This paper presents a thorough analysis of S-scheme heterojunction photocatalysts based on chalcogenides.Following an introduction to the fundamental characteristics and benefits of S-scheme heterojunction photocatalysts,various chalcogenide-based S-scheme heterojunction photocatalyst synthesis techniques are summarized.These photocatalysts are used in numerous significant photocatalytic reactions,in-cluding the reduction of carbon dioxide,synthesis of hydrogen peroxide,conversion of organic matter,generation of hydrogen from water,nitrogen fixation,degradation of organic pollutants,and sterilization.In addition,cutting-edge characterization techniques,including in situ characterization techniques,are discussed to validate the steady and transient states of photocatalysts with an S-scheme heterojunction.Finally,the design and challenges of chalcogenide-based S-scheme heterojunction photocatalysts are explored and recommended in light of state-of-the-art research. 展开更多
关键词 PHOTOCATALYSIS CHALCOGENIDE S-scheme heterojunction Charge separation Application
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Bioaccumulation,subcellular distribution and chemical forms of cadmium in Aster subulatus Michx.
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作者 LIANG Xue-lian CHEN Wei +7 位作者 JIANG Wen-yan LIAO Jie YANG Yu-xia WANG Hai-jun LI Hui-ling LU Wei-fan WANG Tian-shun XIE Hong-zhao 《南方农业学报》 CAS CSCD 北大核心 2024年第8期2386-2395,共10页
【Objective】Through analyzing the bioaccumulation capacity,subcellular distribution and chemical forms of cadmium(Cd)in Aster subulatus Michx.,this study was to provide reference for revealing the Cd tolerance mechan... 【Objective】Through analyzing the bioaccumulation capacity,subcellular distribution and chemical forms of cadmium(Cd)in Aster subulatus Michx.,this study was to provide reference for revealing the Cd tolerance mechanism of A.subulatus Michx.【Method】After cultured for 24 d under the action of Hoagland nutrient solution and gradient Cd concentrations(0,30,60 and 90 mg/L),A.subulatus Michx.were harvested,and its leaf,stem and root were treated by differential centrifugation,chemical reagent extraction,and digested with graphite digester,respectively,then the Cd content in the root,stem and leaf were determined by atomic absorption spectroscopy.【Result】The experimental results indicated that the bioaccumulation capacity of Cd in A.subulatus Michx.was root>stem>leaf,and the maximum Cd concentration in the root,stem and leaf of A.subulatus Michx.were 130.74,78.69 and 56.62 mg/kg(fresh matter),respectively.Most of Cd stored in the cell wall and the soluble fractions of the root and leaf of A.subulatus Michx.,with only a smaller portion Cd in organelle fraction.Analysis result of subcellular Cd content showed that 52.27%-58.61%of Cd for root was mainly stored in the soluble fraction,but 42.10%-63.28%of Cd for leaf was mainly stored in the cell wall fraction.The concentration of pectates and protein integrated-Cd was higher in the root and leaf compared to other chemical forms Cd.Pectates and protein integrated-Cd was the main chemical forms Cd in the root and leaf of A.subulatus Michx.,and their percentages were 68.91%-74.80%and 57.38%-83.80%,respectively.Cd treatment could significantly increase the proportion of water-soluble organic acid Cd from 13.64%to 22.72%in root and undissolved phosphate Cd from 10.02%to 32.78%in leaf with increasing Cd concentration in the culture medium.【Conclusion】The root,stem and leaf of A.subulatus Michx.has strong bioaccumulation capacity to Cd,Cd is primarily stored in the soluble fractions of the root and cell wall fractions of the leaf,and less toxic pectates and protein integrated-Cd is the main chemical forms Cd in the root and leaf of A.subulatus Michx.,this might be the main mechanism of Cd tolerance in A.subulatus Michx. 展开更多
关键词 Aster subulatus Michx. CADMIUM BIOACCUMULATION chemical form subcellular distribution
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Research and development on mechanism of removal of indoor volatile organic compounds by plants
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作者 LI Fangwei CUI Long +2 位作者 CHENG Yan XUE Yonggang HUANG Yu 《地球环境学报》 CSCD 2024年第4期583-595,共13页
Background,aim,and scope Owing to the rapid development of modernisation and urbanisation,living standards have gradually improved.However,the widespread use of high-energy-consuming indoor appliances and furniture ha... Background,aim,and scope Owing to the rapid development of modernisation and urbanisation,living standards have gradually improved.However,the widespread use of high-energy-consuming indoor appliances and furniture has made indoor environments a primary environmental problem affecting human health.Sick building syndrome(SBS)and building-related illness(BRI)have occurred,and indoor air conditions have been extensively studied.Common indoor pollutants include CO,CO_(2),volatile organic compounds(VOCs)(such as the formaldehyde and benzene series),NOx(NO and NO_(2)),and polycyclic aromatic hydrocarbons(PAHs).VOCs have replaced SO_(2)as the“The Fourteenth Five-Year Plan”urban air quality assessment new indicators.Indoor VOCs can cause diseases such as cataract,asthma,and lung cancer.To protect human health,researchers have proposed several indoor air purification technologies,including adsorption,filtration,electrostatic dust removal,ozonation,and plant purification.However,each technology has drawbacks,such as high operating costs,high energy consumption,and the generation of secondary waste or toxic substances.Plant degradation of VOCs as a bioremediation technology has the characteristics of low cost,high efficiency,and sustainability,thereby becoming a potential green solution for improving indoor air quality.This study introduces the research status and mechanism of plant removal of indoor VOCs and provides an experimental basis and scientific guidance for analysing the mechanism of plant degradation of pollutants.Materials and methods This study reviews studies on the harm caused by indoor pollutants to human health and related sources,mainly investigating the degradation of indoor formaldehyde,BTEX(benzene,toluene,ethylbenzene,and xylene)plant mechanisms,and research results.Results Plants can remove VOCs via stomatal and non-stomatal adsorption,interfoliar microbial,rhizosphere microbial,and growth media.Benzene,toluene,and xylene(BTX)are adsorbed by pores,hydroxylated into fumaric acid,and then removed into CO_(2) and H_(2)O by TCA.Formaldehyde enters plant leaves through the stomata and epidermal waxy substances and is adsorbed.After the two steps of enzymatic oxidation,formic acid and CO_(2) are generated.Finally,it enters the Calvin cycle and removes glucose and other nontoxic compounds.Discussion The non-stomatal degradation of VOCs can be divided into adsorption by cuticular wax and active adsorption by plant surface microorganisms.The leaf epidermal waxy matter content and the lipid composition of the epidermal membrane covering the plant surface play important roles in the non-stomatal adsorption of indoor air pollutants.The leaf margin of a plant is an ecological environment containing various microbial communities.The endophytic and inoculated microbiota in plant buds and leaves can remove VOCs(formaldehyde and BTEX).Formaldehyde can be directly absorbed by plant leaves and converted into organic acids,sugars,CO_(2) and H_(2)O by microbes.Bioremediation of indoor VOCs is usually inefficient,leading to plant toxicity or residual chemical substance volatilisation through leaves,followed by secondary pollution.Therefore,plants must be inoculated with microorganisms to improve the efficiency of plant degradation of VOCs.However,the effectiveness of interfoliar microbial removal remains largely unknown and several microorganisms are not culturable.Therefore,methods for collecting,identifying,and culturing microorganisms must be developed.As the leaf space is a relatively unstable environment,the degradation of VOCs by rhizosphere microorganisms is equally important,and formaldehyde is absorbed more by rhizosphere microorganisms at night.The inoculation of bacteria into the rhizosphere improves the efficiency of plants in degrading VOCs.However,most of these studies were conducted in simulation chambers.To ensure the authenticity of these conclusions,the ability of plants to remove indoor air pollutants must be further verified in real situations.Conclusions Plant purification is an economical,environment-friendly,and sustainable remediation technology.This review summarises the mechanisms of VOC plant degradation and presents its limitations.Simultaneously,it briefly puts forward a plant selection scheme according to different temperatures,light,and specific VOCs that can be absorbed to choose the appropriate plant species.However,some studies have denied the purification effect of plants and proposed that numerous plants are required to achieve indoor ventilation effects.Therefore,determining the ability of plants to remove indoor VOCs requires a combination of realistic and simulated scenarios.Recommendations and perspectives Plants and related microorganisms play an important role in improving indoor air quality,therefore,the effect of plants and the related microorganisms on improving indoor air quality must be studied further and the effect of plants on indoor VOCs will be the focus of future research. 展开更多
关键词 PLANTS VOCS removal mechanism indoor air purification MICROORGANISM
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Atomic orbitals modulated dual functional bimetallic phosphides derived from MOF on MOF structure for boosting high efficient overall water splitting
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作者 Bohan An Weilong Liu +3 位作者 Jipeng Dong Ning Li Yangqin Gao Lei Ge 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第10期113-125,共13页
The electronic modulation characteristics of efficient metal phosphide electrocatalysts can be utilized to tune the performance of oxygen evolution reaction(OER).However,improving the overall water splitting performan... The electronic modulation characteristics of efficient metal phosphide electrocatalysts can be utilized to tune the performance of oxygen evolution reaction(OER).However,improving the overall water splitting performance remains a challenging task.By building metal organic framework(MOF)on MOF heterostructures,an efficient strategy for controlling the electrical structure of MOFs was presented in this study.ZIF-67 was in-situ synthesized on MIL-88(Fe)using a two-step self-assembly method,followed by low-temperature phosphorization to ultimately synthesize FeP-CoP_(3)bimetallic phosphides.By combining atomic orbital theory and theoretical calculations(density functional theory),the results reveal the successful modulation of electronic orbitals in FeP-CoP_(3)bimetallic phosphides,which are synthesized from MOF on MOF structure.The synergistic impact of the metal center Co species and the phase conjugation of both kinds of MOFs are responsible for this regulatory phenomenon.Therefore,the catalyst demonstrates excellent properties,demonstrating HER 81 mV(η10)in a 1.0 mol L^(−1)KOH solution and OER 239 mV(η50)low overpotentials.The FeP-CoP_(3)linked dual electrode alkaline batteries,which are bifunctional electrocatalysts,have a good electrocatalytic ability and may last for 50 h.They require just 1.49 V(η50)for total water breakdown.Through this technique,the electrical structure of electrocatalysts may be altered to increase catalytic activity. 展开更多
关键词 Transition metal phosphides MOF on MOF Atomic orbital theory Density functional theory calculation
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Enhancing Na^(+) diffusion dynamics and structural stability of O3-NaMn_(0.5)Ni_(0.5)O_(2)cathode by Sc and Zn dual-substitution
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作者 Bin-bin WANG Yi-ming FENG +8 位作者 Xin LUO Qun HUANG Zi-xing HOU Ya-qin WU Peng-yu WANG Yu-yang QI Qing-fei MENG Wei-feng WEI Liang-jun ZHOU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第10期3344-3357,共14页
Sc and Zn were introduced into O3-NaMn_(0.5)Ni_(0.5)O_(2)(NaMN)using the combination of solution combustion and solid-state method.The effect of Sc and Zn dual-substitution on Na^(+) diffusion dynamics and structural ... Sc and Zn were introduced into O3-NaMn_(0.5)Ni_(0.5)O_(2)(NaMN)using the combination of solution combustion and solid-state method.The effect of Sc and Zn dual-substitution on Na^(+) diffusion dynamics and structural stability of NaMN was investigated.The physicochemical characterizations suggest that the introduction of Sc and Zn broaden Na^(+) diffusion channels and weaken the Na—O bonds,thereby facilitating the diffusion of sodium ions.Simulations indicate that the Sc and Zn dual-substitution decreases the diffusion barrier of Na-ions and improves the conductivity of the material.The dual-substituted NaMn_(0.5)Ni_(0.4)Sc_(0.04)Zn_(0.04)O_(2)(Na MNSZ44)cathode delivers impressive cycle stability with capacity retention of 71.2%after 200 cycles at 1C and 54.8%after 400 cycles at 5C.Additionally,the full cell paired with hard carbon anode exhibits a remarkable long-term cycling stability,showing capacity retention of 64.1%after 250 cycles at 1C.These results demonstrate that Sc and Zn dual-substitution is an effective strategy to improve the Na^(+) diffusion dynamics and structural stability of NaMN. 展开更多
关键词 layered oxide cathode Sc and Zn dual-substitution structural stability Na^(+)diffusion dynamics
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C-H bond activation of propane on Ga_(2)O_(2)^(2+) in Ga/H-ZSM-5 and its mechanistic implications
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作者 Zhaoqi Zhao Yunzhu Zhong +1 位作者 Xiaoxia Chang Bingjun Xu 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第9期32-43,共12页
Propane dehydrogenation(PDH)on Ga/H-ZSM-5 catalysts is a promising reaction for propylene production,while the detail mechanism remains debatable.Ga_(2)O_(2)^(2+) stabilized by framework Al pairs have been identified ... Propane dehydrogenation(PDH)on Ga/H-ZSM-5 catalysts is a promising reaction for propylene production,while the detail mechanism remains debatable.Ga_(2)O_(2)^(2+) stabilized by framework Al pairs have been identified as the most active species in Ga/H-ZSM-5 for PDH in our recent work.Here we demonstrate a strong correlation between the PDH activity and a fraction of Ga_(2)O_(2)^(2+) species corresponding to the infrared GaH band of higher wavenumber(GaHHW)in reduced Ga/H-ZSM-5,instead of the overall Ga_(2)O_(2)^(2+) species,by employing five H-ZSM-5 supports sourced differently with comparable Si/Al ratio.This disparity in Ga_(2)O_(2)^(2+) species stems from their differing capacity in completing the catalytic cycle.Spectroscopic results suggest that PDH proceeds via a two-step mechanism:(1)C-H bond activation of propane on H-Ga_(2)O_(2)^(2+) species(rate determining step);(2)β-hydride elimination of adsorbed propyl group,which only occurs on active Ga_(2)O_(2)^(2+) species corresponding to GaHHW. 展开更多
关键词 Propane dehydrogenation Ga_(2)O_(2)^(2+) Activation of C-H bond Ga species
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