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Crystallinity-defect matching relationship of g-C_(3)N_(4): Experimental and theoretical perspectives
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作者 yuhan li Ziteng Ren +5 位作者 Zhengjiang He Ping Ouyang Youyu Duan Wendong Zhang Kangle Lv Fan Dong 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第4期623-658,共36页
Good crystallinity can reduce the charge recombination centers caused by defects,whilst structures with strong polycondensation have high charge mobility,leading to more charge transfer to the material surface for rea... Good crystallinity can reduce the charge recombination centers caused by defects,whilst structures with strong polycondensation have high charge mobility,leading to more charge transfer to the material surface for reaction.Much effort has been put into the preparation of a highly efficient g-C_(3)N_(4) with defects to improve its application potential under the premise in high crystallinity.Hence,this review paper emphasizes the importance to balance the defect and crystallinity of g-C_(3)N_(4).In addition,detailed discussion on the relationship between defects and activity of g-C_(3)N_(4) was carried out based on its applications in environmental purification(e.g.,VOCs oxidation,NO_(x) oxidation,H_(2)O_(2) evolution,sterilization,pesticide oxidation)and energy conversion(H_(2) evolution,N_(2) fixation and CO_(2) reduction).Lastly,the challenge in developing more efficient defective g-C_(3)N_(4) photocatalytic materials is summarized. 展开更多
关键词 PHOTOCATALYSIS DEFECT G-C_(3)N_(4) CRYSTALLINITY APPLICATION
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Solving the Urban Domestic Waste Classification Dilemma from a Coalitional Game Perspective
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作者 yuhan li Xuanqi liu Xiujuan Wang 《Journal of Environmental Protection》 CAS 2023年第4期243-253,共11页
The effective classification of urban domestic waste is the key to achieve a “waste-free city” and provides an essential guarantee for resource utilization. This article takes a coalitional game perspective to study... The effective classification of urban domestic waste is the key to achieve a “waste-free city” and provides an essential guarantee for resource utilization. This article takes a coalitional game perspective to study the dilemmas in urban domestic waste separation from the cooperative interaction of residents, government, and enterprises. The study finds that urban domestic waste classification in China is currently facing many problems, focusing on: 1) insufficient consensus among residents, 2) shortage of input funds, 3) corporate profitability difficulties, 4) weak policy constraints, and 5) difficulties in integrating goals. In this regard, each participating body still needs to focus on collective interests, coalitional games, break the dilemma society, and promote the long-term management of urban domestic waste. 展开更多
关键词 Waste Classification Coalitional Game Multiple Subjects
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The Fulfillment of Government Responsibilities in the Collaborative Governance of Rural Water Pollution
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作者 Xuanqi liu yuhan li Xiujuan Wang 《Open Journal of Applied Sciences》 CAS 2023年第4期496-507,共12页
Rural environmental pollution is becoming more and more serious, which has become an important problem to be solved urgently in our country under the background of the new era. Protecting the ecological environment is... Rural environmental pollution is becoming more and more serious, which has become an important problem to be solved urgently in our country under the background of the new era. Protecting the ecological environment is one of the important functions of the government, and protecting the rural water environment is the unshirkable responsibility of the local governments. As the main body of rural water pollution control, how to define and fulfill the local governments’ responsibilities is of great significance to the advancement of the overall governance work. This paper starts from the local governments, which are the important main body of rural environmental governance. By comparing the similarities and differences between the performance of government responsibilities under the traditional governance model and the collaborative governance model, clarifies the governance responsibilities of the local governments. And further explores the effective measures for the government to play the main role, fulfill the main responsibilities, and participate in the collaborative governance of rural water pollution. 展开更多
关键词 Fulfillment of Government Responsibilities Rural Water Pollution Collaborative Governance
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A Study of the Treatment of Disfiguring Diseases in the “Qian Jin Fang”
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作者 yuhan li Yang Zhao 《Journal of Clinical and Nursing Research》 2024年第3期200-206,共7页
Traditional Chinese medicine(TCM)has been passed down for more than 2,000 years.TCM beauty products driven by the principles of identification and treatment with various dosage forms and exhibit mild and safe efficacy... Traditional Chinese medicine(TCM)has been passed down for more than 2,000 years.TCM beauty products driven by the principles of identification and treatment with various dosage forms and exhibit mild and safe efficacy are bound to become a main component of the beauty industry in the future.Xu once commented that“Qian Jin Fang”is different from the traditional prescription system,which emphasizes the use of medicines.In this paper,we mainly selected the prescriptions for the treatment of disfigurement diseases such as acne,scarring,black dryness,face hyperpigmentation,black mole,and rosacea from the article titled,“Upper Seven Orifices Disease-Facial Medicine IX”in the Bei Ji Qian Jin Yao Fang[1].By studying and analyzing the original composition of the formula,understanding the etiology and pathogenesis of the disease,and exploring the characteristics of the formula concerning the efficacy of TCM,their properties,flavors,and meridians,we summarized the characteristics of the Qian Jin Fang.It is based on the external treatment of disfigurement diseases,with a wide variety of drugs,flexibility,and accuracy.This method draws upon analogies while utilizing excipients and harmonizers to focus on the combined healing approach of treatment and nourishment. 展开更多
关键词 Qian jin fang External treatment Disfiguring diseases ACNE
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Bacterial Cellulose Composite Solid Polymer Electrolyte With High Tensile Strength and Lithium Dendrite Inhibition for Long Life Battery 被引量:1
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作者 yuhan li Zongjie Sun +9 位作者 Dongyu liu Shiyao Lu Fei li Guoxin Gao Min Zhu Mingtao li Yanfeng Zhang Huaitian Bu Zhiyu Jia Shujiang Ding 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2021年第3期434-443,共10页
The development of metallic lithium anode is restrained by lithium dendrite growth during cycling.The solid polymer electrolyte with high mechanical strength and lithium ion conductivity could be applied to inhibit li... The development of metallic lithium anode is restrained by lithium dendrite growth during cycling.The solid polymer electrolyte with high mechanical strength and lithium ion conductivity could be applied to inhibit lithium dendrite growth.To prepare the high-performance solid polymer electrolyte,the environment-friendly and cheap bacterial cellulose(BC)is used as filler incorporating with PEO-based electrolyte owing to good mechanical properties and Li salts compatibility.PEO/Li TFSI/BC composite solid polymer electrolytes(CSPE)are prepared easily by aqueous mixing in water.The lithium ion transference number of PEO/Li TFSI/BC CSPE is 0.57,which is higher than PEO/Li TFSI solid polymer electrolyte(SPE)(0.409).The PEO/Li TFSI/BC CSPE exhibits larger tensile strength(4.43 MPa)than PEO/Li TFSI SPE(1.34 MPa).The electrochemical window of composite electrolyte is widened 1.43 V by adding BC.Density functional theory calculations indicate that flex of PEO chains around Li atoms is suppressed,suggesting the enhanced lithium ion conductivity.Frontier molecular orbitals results suggest that an unfavorable intermolecular charge transfer lead to achieve higher potential for BC composite electrolyte.All solid-state Li metal battery with PEO/Li TFSI/BC CSPE delivers longer cycle life for 600 cycles than PEO/Li TFSI SPE battery(50 cycles).Li symmetrical battery using PEO/Li TFSI/BC CSPE could be stable for 1160 h. 展开更多
关键词 all solid-state battery bacterial cellulose composite polymer electrolyte DFT calculations HOMO and LUMO
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An Analysis of the Factors Influencing Cavitation in the Cylinder Liner of a Diesel Engine 被引量:1
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作者 Dehui Tong Shunshun Qin +2 位作者 Quan liu yuhan li Jiewei lin 《Fluid Dynamics & Materials Processing》 EI 2022年第6期1667-1682,共16页
Avoiding cavitation inside the water jacket is one of the most important issues regarding the proper design of a diesel engine’s cylinder liner.Using CFD simulations conducted in the frame of a mixture multiphase app... Avoiding cavitation inside the water jacket is one of the most important issues regarding the proper design of a diesel engine’s cylinder liner.Using CFD simulations conducted in the frame of a mixture multiphase approach,a moving grid technology and near-wall cavitation model,in the present study the factors and fluid-dynamic patterns that influence cavitation are investigated from both macroscopic and mesoscopic perspectives.Several factors are examined,namely:wall vibration,water jacket width,initial cavitation bubble radius,coolant temperature,and number of bubbles.The results show that reducing the cylinder liner vibration intensity can significantly weaken the cavitation.Similarly,increasing the water jacket width is instrumental in avoiding cavitation.Increasing the coolant temperature reduces the microjet velocity related to bubble collapse,while increasing the number of bubbles produces a much larger water hammer pressure that can cause more damage to the cylinder liner. 展开更多
关键词 CAVITATION cavitation dynamics diesel engine two-phase flow water hammer
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Analysis of the Drug Sensitivity of Escherichia coli Isolated from Sheep in Yangling,Shaanxi Province 被引量:1
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作者 ling li yuhan li +2 位作者 Lu DAI Haoyuan FENG Chaoxi CHEN 《Agricultural Biotechnology》 CAS 2018年第5期119-121,共3页
This study was conducted to investigate the drug sensitivity of Escherichia coli isolated from sheep, providing data reference for clinical medication. Fifty-four samples were collected from a certain sheep farm in Ya... This study was conducted to investigate the drug sensitivity of Escherichia coli isolated from sheep, providing data reference for clinical medication. Fifty-four samples were collected from a certain sheep farm in Yangling, Shaanxi Province for E. coli isolation and identification, and K-B disk diffusion method was used to carry out the dug sensitivity test of 40 E. coli to the eight antimicrobials of spectinomycin, amikacin, tobramycin, enrofloxacin, nalidixic acid, levofloxacin, salafloxacin and ciprofloxacin. The results showed that there were 40 positive E. coli strains and the isolation rate was 74.7%. The resistance rates of the 40 E. coli to spectinomycin, amikacin,tobramycin and nalidixic acid were 85%, 95%, 97.5% and 87.5%, respectively, while the resistance rate to enrofloxacin, levofloxacin, salafloxacin and ciprofloxacin were relatively low and the resistance rates were 35%, 20%, 25% and 17.5%, respectively. The isolates showed different levels of drug resistance to eight antimicrobials and the highest resistance rate was 97.5%. It reminds that the sheep farm should strictly control the dosage according to the antimicrobial sensitive data in clinic. 展开更多
关键词 SHEEP Escherichia coli Drug resistance rate
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Sterilization mechanism of helium/helium-oxygen atmospheric-pressure pulsed dielectric barrier discharge on membrane surface
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作者 陈星宇 李雨菡 +1 位作者 李孟琦 熊紫兰 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第12期173-181,共9页
Pulsed dielectric barrier discharge(PDBD) exhibits several applications in different fields;however,the interaction of its components with substances remains a key issue.In this study,we employed experimental and nume... Pulsed dielectric barrier discharge(PDBD) exhibits several applications in different fields;however,the interaction of its components with substances remains a key issue.In this study,we employed experimental and numerical modeling to investigate the interactions between different PDBD components and substances in pure helium and a helium-oxygen mixture.A membrane comprising a Staphylococcus aureus strain was utilized as the treatment object to demonstrate the trace actions of the evolutions and distributions of certain components on the surface of the substance.The results revealed that the shapes and sizes of the discharging area and inhibition zone differed between groups.Under a pure helium condition,a discharge layer existed along the membrane surface,lying beside the main discharging channel within the electrode area.Further,an annulus inhibition zone was formed at the outer edge of the electrode in the pure helium group at 30 s and 1 min,and this zone extended to a solid circle at 2 min with a radius that was~50% larger than that of the electrode radius.Nevertheless,the discharging channel and inhibition zone in the helium-oxygen mixture were constrained inside the electrode area without forming any annulus.A 2D symmetrical model was developed with COMSOL to simulate the spatiotemporal distributions of different particles over the membrane surface,and the result demonstrated that the main components,which formed the annulus inhibition zone under the pure helium condition,contributed to the high concentration of the He^(+)annulus that was formed at the outer edge of the electrode.Moreover,O^(+)and O_(2)^(+)were the main components that killed the bacteria under the helium-oxygen mixture conditions.These results reveal that the homogenization treatment on a material surface via PDBD is closely related to the treatment time and working gas. 展开更多
关键词 pulsed dielectric barrier discharge interaction mechanism numerical modeling spatiotemporal distribution of species treatment substance
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以磺化聚酰亚胺为基材的离子聚合物金属复合材料 被引量:1
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作者 李玉邯 王喜 +1 位作者 高连勋 金日哲 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2019年第4期142-145,共4页
以磺化聚酰亚胺(SPI)作为离子聚合物金属复合材料(IPMC)的基体材料,通过化学沉积法制备新型IPMC,并对材料的性能进行了测试。扫描电子显微镜显示金属铂和银成功涂镀到SPI基材上,镀层厚度为12μm;并对以SPI和Nafion膜为基材制备的IPMC材... 以磺化聚酰亚胺(SPI)作为离子聚合物金属复合材料(IPMC)的基体材料,通过化学沉积法制备新型IPMC,并对材料的性能进行了测试。扫描电子显微镜显示金属铂和银成功涂镀到SPI基材上,镀层厚度为12μm;并对以SPI和Nafion膜为基材制备的IPMC材料的含水量、表面电阻和电制动性能进行测试。实验结果显示,与传统的Nafion为基材的IPMC材料相比,以SPI为基材的新型IPMC材料的含水量明显高于Nafion基材制备的IPMC,并且电致动性能更好,产生的尖端位移远远高于Nafion基材制备的IPMC,并且灵敏度更高。这些性能显示磺化聚酰亚胺有望替代Nafion膜作为电活性聚合物的基体材料。 展开更多
关键词 磺化聚酰亚胺 离子聚合物-金属复合材料 电活性聚合物
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辐射交联对磺化聚酰亚胺作为燃料电池用质子交换膜性能的影响
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作者 李玉邯 高连勋 金日哲 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2020年第12期137-141,150,共6页
为了提高磺化聚酰亚胺膜的综合性能,特别是水解稳定性,文中以60Co为辐射源,对磺化聚酰亚胺进行γ射线辐射。辐射后,膜的相对分子质量通过凝胶渗透色谱进行测试,测试结果显示,辐射后膜的数均分子量和重均分子量都有明显提高。膜的分子结... 为了提高磺化聚酰亚胺膜的综合性能,特别是水解稳定性,文中以60Co为辐射源,对磺化聚酰亚胺进行γ射线辐射。辐射后,膜的相对分子质量通过凝胶渗透色谱进行测试,测试结果显示,辐射后膜的数均分子量和重均分子量都有明显提高。膜的分子结构由核磁和红外光谱测试确定,结果表明辐射和未辐射膜的核磁谱图和红外光谱谱图基本不变。对辐照不同时间交联膜的含水量、尺寸稳定性、质子传导率、膜稳定性和力学性能进行了测试,结果显示,24 h辐射处理能提高膜的综合性能,特别是水解稳定性得到了显著提高,膜在100℃去离子水中可以稳定存在960 h,是未交联膜的5.6倍。辐射对质子交换膜的氧化稳定性和力学性能都有提高,甲醇渗透率有所减小。辐射24 h的磺化聚酰亚胺膜仍保持了较高的质子传导率,在80℃去离子水中膜的导电率仍可高达到0.145 S/cm。实验表明适度辐射交联是提高磺化聚酰亚胺膜综合性能的一种有效方法。 展开更多
关键词 磺化聚酰亚胺 辐射交联 质子交换膜 燃料电池
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利用Bi的SPR效应增强Bi_2WO_6的可见光催化NO氧化去除性能(英文) 被引量:7
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作者 张荔 杨超 +7 位作者 吕康乐 陆亚超 李覃 伍晓锋 李宇涵 黎小芳 范佳杰 李玫 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第5期755-764,共10页
作为大气中的典型污染物之一,化石燃料燃烧产生的NO不仅会引起酸雨,还会影响人体呼吸系统.半导体光催化技术可以利用太阳能和空气中的氧气来分解环境污染物,因而得到了国内外学者的广泛关注.作为最具代表性的半导体光催化材料,TiO_2虽... 作为大气中的典型污染物之一,化石燃料燃烧产生的NO不仅会引起酸雨,还会影响人体呼吸系统.半导体光催化技术可以利用太阳能和空气中的氧气来分解环境污染物,因而得到了国内外学者的广泛关注.作为最具代表性的半导体光催化材料,TiO_2虽然具有较强的氧化能力和优异的生物相容性,但是其禁带宽度较大(3.2 eV)而只能被紫外光激发,无法充分利用太阳能.因此,开发新型可见光响应的半导体催化材料具有重要意义.Bi_2WO_6是一种独特的具有层状结构半导体光催化材料,因其具有可见光响应性能而受到了广泛关注;但是可见光响应范围窄(禁带宽度2.6?2.8 eV)以及其较快的光生载流子复合,导致Bi_2WO_6其光催化效率不高,迫切需要采取有效措施对Bi_2WO_6进行改性.贵金属(诸如金和银)纳米粒子可见光区的表面等离子体效应(SPR),可以用来增强半导体材料的可见光催化性能.但是,贵金属的价格昂贵,难以满足实际需求.近来的研究发现,非贵金属Bi同样具有类似的表面等离子体效应.因此,本文选用以乙二醇为还原剂,通过低温还原Bi(NO_3)_3的方式,在花球Bi_2WO_6表面,成功制备了沉积了Bi纳米球复合光催化次材料.本文用NO的可见光催化氧化来评价Bi/Bi_2WO_6复合材料的光催化性能的可见光催化性能,所使用的光源为可见光LED灯(λ>400 nm).结果发现:(1)单一组分的Bi金属和Bi_2WO_6前驱体花球均表现出非常差的光催化活性,NO去除率分别仅为7.7%和8.6%;(2)随着Bi纳米球的负载量从0增加至10 wt%,复合材料Bi/Bi_2WO_6的NO去除效率从12.3%稳定增加至53.1%至20 wt%时开始降低.这可能是由于Bi纳米球阻碍了Bi_2WO_6对光的吸收;(3)改性后的Bi/Bi_2WO_6具有良好的可见光催化稳定性,循环使用在五次后其活性变化不大.光催化机理研究结果显示,Bi/Bi_2WO_6增强的可见光NO去除性能归因于Bi纳米球的SPR效应.在可见光照射下,Bi纳米球的SPR效应产生的电场可以显著促进Bi_2WO_6的光生载流子分离效率.同时,Bi纳米球可以快速转移Bi_2WO_6导带上的光生电子,生成超氧游离基(·O_2~?),从而抑制了光生电子和空穴的复合.Bi_2WO_6表面的空穴可以被表面吸附水捕获,产生羟基自由基(·OH).在活性氧物种·OH和·O_2~?的不断进攻作用下,NO最终被氧化.本文为宽禁带半导体的非贵金属敏化,提升其可见光催化性能解决环境问题提供了新思路. 展开更多
关键词 Bi2WO6 表面等离子体 光催化 氧化氮
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光催化的氟效应 被引量:3
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作者 黎小芳 伍晓锋 +3 位作者 刘升卫 李宇涵 范佳杰 吕康乐 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第10期1451-1467,共17页
半导体光催化因有望可持续地解决日益严峻的环境与能源问题而得到国内外学者的广泛关注.但是,以TiO2为代表的半导体光催化材料,存在光响应范围窄和光生载流子容易复合的问题,导致其光催化效率不高.为了提高半导体光催化效率,科学家们采... 半导体光催化因有望可持续地解决日益严峻的环境与能源问题而得到国内外学者的广泛关注.但是,以TiO2为代表的半导体光催化材料,存在光响应范围窄和光生载流子容易复合的问题,导致其光催化效率不高.为了提高半导体光催化效率,科学家们采取了许多策略对本征半导体光催化剂进行修饰改性,如表面敏化、贵金属沉积、元素掺杂和半导体复合等,以拓展光吸收范围和促进光生载流子分离.近来,高能面TiO2纳米晶的报道为高性能半导体光催化材料的设计提供了新的思路.在所有对TiO2进行修饰改性的元素里面,氟因其独特的性能而对TiO2光催化产生了深远影响:(1)(在酸性溶液里面)氟离子与TiO2强烈的配位作用(化学吸附)会改变TiO2光催化材料表面的化学结构,生成氟化钛(≡Ti-F),进而影响污染物在催化剂表面的吸附(反应式(1));≡Ti-OH+H++F-→≡Ti-F+H2O(1)(2)吸附在TiO2表面的氟离子,很难被空穴氧化成氟自由基(EθF·/F-=3.6 V vsNHE),只能将溶剂水氧化成羟基自由基(·OH).与本征TiO2空穴氧化产生的表面吸附态羟基自由基(·OHbounded)不同(反应式(2)),表面氟修饰后空穴氧化溶剂水产生的羟基自由基(反应式(3)),是可以脱离催化剂表面(在溶液中自由扩散的),也就是游离态羟基自由基(·OHfree).≡Ti-OH+h+→≡Ti····OH (·OHbounded)(2)≡Ti-F+H2O+h+→≡Ti-F+·OHfree+H+(3)本文主要从以下几个方面综述了氟效应对半导体光催化的影响:(1)TiO2光催化的表面氟效应,包括游离自由基效应、表面电子结构效应和电子清除剂效应;(2)TiO2光催化的氟掺杂效应,包括氟离子掺杂、氟离子与非金属离子共掺杂、以及氟离子与金属离子共掺杂;(3)TiO2的氟离子形貌控制效应,包括空心结构TiO2、高能面TiO2和介晶TiO2.此外,我们也将氟效应拓展到其它非TiO2半导体上,包括Bi2WO4, BiPO4, Fe2O3, SrTiO3和g-C3N4.本文还总结了氟效应在半导体光催化领域的应用,包括(1)化学品的光催化选择性氧化;(2)污染物的光催化选择性降解;(3)光催化分解水产氢;(4)光催化还原二氧化碳;(5)制备高热稳定性TiO2.最后总结了氟效应的优缺点,并对氟效应的前景进行了展望.现在仪器表征技术(特别是原位表征技术)的快速发展,为半导体光催化氟效应的深入研究提供了新的武器.将氟效应与其它方式的耦合,如表面等离子体效应、晶体缺陷和单原子催化,来进一步提高半导体光催化性能,是未来氟效应研究的发展方向. 展开更多
关键词 二氧化钛 光催化 掺杂 表面修饰
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非贵金属助催化剂MXene在光催化领域应用的研究进展 被引量:5
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作者 李开宁 张苏舒 +2 位作者 李宇涵 范佳杰 吕康乐 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第1期3-14,共12页
环境友好型半导体光催化是当前最具前景的光催化技术之一,它不仅能够将太阳能转化为化学能以解决能源危机,还可以将污染物降解矿化从而解决环境问题.但是,传统的半导体光催化剂受限于光利用率低、光生载流子复合率高、稳定性较差等几个... 环境友好型半导体光催化是当前最具前景的光催化技术之一,它不仅能够将太阳能转化为化学能以解决能源危机,还可以将污染物降解矿化从而解决环境问题.但是,传统的半导体光催化剂受限于光利用率低、光生载流子复合率高、稳定性较差等几个方面,无法达到理想的光催化效果.在半导体光催化剂上负载助催化剂是提升光催化效率的有效策略之一.负载助催化剂能够增强光生电荷在半导体与助催化剂界面间的传输,提供额外的催化活性位点,增强光捕获能力,因而被广泛应用于光催化剂的改性.目前广泛使用的贵金属助催化剂包括Au,Ag,Pt,Ru等,虽然这些贵金属助催化剂性能优异,但是它们存在储量少和成本高的问题,严重影响其规模化应用.因此,开展高效且成本低廉的非贵金属助催化剂的研究非常必要.近来,一种新型二维过渡金属材料(MXene)因其具有独特的二维层状结构、优异的导电性能、出色的光学和热力学性质而成为催化领域的研究热点.本文综述了有关非贵金属助催化剂MXene在光催化领域的最新研究进展,内容包括:(1)MXene材料的体相与表面结构特性;(2)薄层MXene的制备方法,例如氢氟酸刻蚀法、氢氟酸替代物刻蚀法以及熔融氟盐刻蚀法;(3)MXene基复合光催化剂的合成及改性策略,包括机械混合、自组装、原位氧化等;(4)MXene辅助增强光催化活性机理.论文还重点介绍了MXene作为助催化剂在光催化领域中的应用,包括光催化分解水产氢、光催化CO2还原、光催化固氮以及有机污染物的光催化降解.最后,论文分析了MXene基异质结光催化剂存在的问题与面临的挑战,并对MXene助催化剂的未来发展进行了展望.主要观点包括:(1)关于光催化分解水、空气净化、合成氨领域的研究较少,需要进一步开展;(2)MXene基异质结光催化剂的反应机理仍存在争议,需采用现代化仪器设备(包括原位表征技术)对其进行更为深入的探究;(3)目前,大多数MXene材料的制备都是通过强腐蚀性的氢氟酸或氢氟酸替代物刻蚀,开发环境友好且高效的MXene制备方法迫在眉睫;(4)阐明MXene表面终端基团的作用有助于提升MXene基复合光催化剂的性能;(5)引入新的改性策略如局域表面等离子体共振效应(LSPR)、缺陷调控、单原子催化(SAC)等来提高MXene基光催化剂的催化性能,是未来MXene基复合催化剂的发展方向. 展开更多
关键词 二维过渡金属材料 光催化降解 产氢 二氧化碳还原 固氮
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The Cenozoic activities of Yangjiang-Yitongdong Fault: insights from analysis of the tectonic characteristics and evolution processes in western Zhujiang(Pearl) River Mouth Basin 被引量:10
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作者 yuhan li Rongwei Zhu +2 位作者 Hailing liu Xuelin Qiu Haibo Huang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第9期87-101,共15页
The Yangjiang-Yitongdong Fault (YJF) is an important NW-trending regional fault, which divides the Zhujiang (Pearl) River Mouth Basin (ZRMB) into western and eastern segments. In Cenozoic, the northern continental mar... The Yangjiang-Yitongdong Fault (YJF) is an important NW-trending regional fault, which divides the Zhujiang (Pearl) River Mouth Basin (ZRMB) into western and eastern segments. In Cenozoic, the northern continental margin of the South China Sea (SCS) underwent continental rifting, breakup, seafloor spreading and thermal subsidence processes, and the Cenozoic activities of YJF is one part of this series of complex processes. Two long NW-trending multichannel seismic profiles located on both sides of the YJF extending from the continental shelf to Continent-Ocean Boundary (COB) were used to study the tectonic and sedimentary characteristics of western ZRMB. Using the 2D-Move software and back-stripping method, we constructed the balance cross-section model and calculated the fault activity rate. Through the comprehensive consideration of tectonic position, tectonic evolution history, featured structure, and stress analysis, we deduced the activity history of the YJF in Cenozoic. The results showed that the YJF can be divided into two segments by the central uplift belt. From 65 Ma to 32 Ma, the YJF was in sinistral motion as a whole, inherited the preexisting sinistral motion of Mesozoic YJF, in which, the southern part of YJF was mainly in extension activity, controlling the formation and evolution of Yunkai Low Uplift, coupled with slight sinistral motion. From 32 Ma to 23.8 Ma, the sinistral motion in northern part of YJF continued, while the sinistral motion in southern part began to stop or shifted to a slightly dextral motion. After 23.8 Ma, the dextral motion in southern part of YJF continued, while the sinistral motion in northern part of YJF gradually stopped, or shifted to the slightly dextral motion. The shift of the YJF strike-slip direction may be related to the magmatic underplating in continent-ocean transition, southeastern ZRMB. According to the analysis of tectonic activity intensity and rift sedimentary structure, the activities of YJF in Cenozoic played a regulating role in the rift extension process of ZRMB. 展开更多
关键词 Yangjiang-Yitongdong FAULT Zhujiang (Pearl) River Mouth BASIN TECTONIC evolution STRIKE slip movement CENOZOIC
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离子交换法制备高光催化活性Bi_2WO_6@Bi_2S_3异质结纳米片(英文) 被引量:3
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作者 黄婷婷 李雨涵 +5 位作者 伍晓峰 吕康乐 李覃 李玫 杜冬云 叶恒朋 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第4期718-727,共10页
社会经济快速发展的同时,也带来了日益严峻的环境污染问题.半导体光催化氧化技术因节能环保而在环境领域有广阔的应用前景.作为最具有代表性的半导体光催化材料,TiO_2因为其禁带宽度(3.2 eV)比较大,只能被紫外光激发,因而对太阳能的利... 社会经济快速发展的同时,也带来了日益严峻的环境污染问题.半导体光催化氧化技术因节能环保而在环境领域有广阔的应用前景.作为最具有代表性的半导体光催化材料,TiO_2因为其禁带宽度(3.2 eV)比较大,只能被紫外光激发,因而对太阳能的利用率较低.作为一种最简单的含铋层状氧化物,Bi_2WO_6的禁带宽度(2.7 eV)相对较小,可以部分利用太阳光中的可见光,因而受到广大研究者的青睐.但是,Bi_2WO_6光催化材料的可见光响应范围较窄,仅能被波长小于450 nm的光激发,且激发后的光生载流子容易复合,导致光催化效率不高.因此,迫切需要对Bi_2WO_6光催化材料进行结构修饰与改性,采用拓展其光响应范围和抑制载流子复合,来提高其光催化活性.本文采用离子交换法原位合成了具有核-壳结构的Bi_2S_3@Bi_2WO_6纳米片,充分利用Bi_2S_3优良的可见光响应性能和半导体异质结光催化剂的构建,来提高Bi_2WO_6的光催化活性.结果表明,随着Na2S·9H2O用量从0增加到1.5 g,所得催化剂的光活性不断提高,X3B的降解速率常数由0.40×10^(-3) min^(-1)增加到6.6×10^(-3) min^(-1),催化剂活性提高了16.5倍.当进一步增加Na2S·9H2O的用量时(1.5.3.0 g),复合催化剂的光活性下降.这是由于过多Na2S·9H2O的引入导致在催化剂表面生成了没有光活性的NaBiS2层(Bi_2S_3+Na_2S=2NaBiS_2),占据了催化剂的活性位点,阻碍了染料分子与催化剂的直接接触.Bi_2WO_6@Bi_2S_3异质结纳米片光活性的提高,可归因于Bi_2S_3的敏化作用极大拓展了复合催化剂的光响应范围;另一方面,Bi_2WO_6和Bi_2S_3两者之间的半导体异质结效应有效促进了光生载流子在空间的有效分离,抑制了光生电子-空穴的复合,从而提高了复合催化剂的催化效率. 展开更多
关键词 BI2S3 Bi2WO6 离子交换 光催化降解 纳米片
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Safety Evaluation of a Compound Lonicera rupicola Hook.f. et & Thomson Injection
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作者 Haoyuan FENG ling li +2 位作者 yuhan li Lu DAI Chaoxi CHEN 《Agricultural Biotechnology》 CAS 2019年第1期108-111,175,共5页
Safety of a compound Lonicera rupicola Hook. f. et & Thomson injection was evaluated by local irritation experiments including conjunctiva,skin and muscle irritant experiments,and the effect on weight gain was stu... Safety of a compound Lonicera rupicola Hook. f. et & Thomson injection was evaluated by local irritation experiments including conjunctiva,skin and muscle irritant experiments,and the effect on weight gain was studied. The results showed that the compound L. rupicola Hook. f. et & Thomson injection had no irritation to rabbit eyes and weak irritation to rabbit ears,and had relatively strong irritation to the leg muscles of the mice. Its metabolism in mice had no abnormal toxicity. 展开更多
关键词 LONICERA rupicola Hook.f.et&Thomson INJECTION Safety evaluation
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Investigation and Analysis on the Causes Affecting the Production of One Pig Farm in Southwest Region
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作者 Lu DAI Chenghong li +3 位作者 yuhan li ling li Haoyuan FENG Chaoxi CHEN 《Agricultural Biotechnology》 CAS 2018年第6期92-94,96,共4页
To analyze the causes affecting production situation of one pig farm in southwest region,group leader,assistant and related staffs in the pig farm were queried,mating and delivery situation of sow and dead-culling sit... To analyze the causes affecting production situation of one pig farm in southwest region,group leader,assistant and related staffs in the pig farm were queried,mating and delivery situation of sow and dead-culling situation ofpigletwere investigated.The results showed that(1) mating situation: mating 691 pigs,returning to love 42 pigs,abortion 4 pigs,mismatching rate was 7.59%.(2) Delivery situation: delivering 175 nests,total birth 2538,total piglet per fetus 14.5,average healthy piglet per fetus 10.12,invalid piglet rate was30.21%.Among them,mummy fetus,dead fetus,weak piglet and deformity accounted for 47.78%,35.64%,10.71% and 5.87% of invalid piglet.(3) Dead-culling situation: dead-culling rate in breeding process was 12.37%.Among them,diarrhea death wasthemain cause,accounting for 44.47%,followed by pressing,falling to the ground,disease,joint swelling,weakness and other causes,and they respectively accounted for 18.58%,13.36%,13.36%,8.56%,5.85% and 0.62%. 展开更多
关键词 Pig MATING ABORTION MUMMY FETUS DEAD FETUS Feeding management procedures
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A non-human primate derived anti-P-selectin glycoprotein ligand-1 antibody curtails acute pancreatitis by alleviating the inflammatory responses
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作者 yuhan li Xiangqing Ding +8 位作者 Xianxian Wu Longfei Ding Yuhui Yang Xiaoliang Jiang Xing liu Xu Zhang Jianrong Su Jianqing Xu Zhiwei Yang 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2023年第11期4461-4476,共16页
Acute pancreatitis(AP)is a devastating disease characterized by an inflammatory disorder of the pancreas.P-selectin glycoprotein ligand-1(PSGL-1)plays a crucial role in the initial steps of the adhesive at process to ... Acute pancreatitis(AP)is a devastating disease characterized by an inflammatory disorder of the pancreas.P-selectin glycoprotein ligand-1(PSGL-1)plays a crucial role in the initial steps of the adhesive at process to inflammatory sites,blockade of PSGL-1 might confer potent anti-inflammatory effects.In this study,we generated two non-human primate derived monoclonal antibodies capable of efficiently targeting human PSGL-1,RH001-6 and RH001-22,which were screened from immunized rhesus macaques.We found that RH001-6,can effectively block the binding of P-selectin to PSGL-1,and abolish the adhesion of leukocytes to endothelial cells in vitro.In vivo,we verified that RH001-6 relieved inflammatory responses and pancreatic injury in both caerulein and L-arginine induced AP models.We also evaluated the safety profile after RH001-6 treatment in mice,and verified that RH001-6 did not cause any significant pathological damages in vivo.Taken together,we developed a novel non-human primate derived PSGL-1 blocking antibody with high-specificity,named RH001-6,which can interrupt the binding of PSGL-1 and P-selectin and attenuate inflammatory responses during AP.Therefore,RH001-6 is highly potential to be further developed into therapeutics against acute inflammatory diseases,such as AP. 展开更多
关键词 Acute pancreatitis PSGL-1 Non-human primate Monoclonal antibody Therapeutic antibody RH001-6 Adhesion of leukocytes to endothelial cells Inflammatory responses Pancreatic injury
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卫星光机载荷热模型参数高效修正方法研究进展
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作者 李玉涵 杨宝玉 +2 位作者 吴亦农 张强 唐晓 《航空学报》 EI CAS CSCD 北大核心 2024年第6期216-234,共19页
卫星光机载荷的光学效能与热设计密切相关,热控系统的模型修正是热设计必不可少的环节。近年国内外涌现出许多基于深度学习和寻优算法的提高热模型修正效率和精确度的方法可供参考,但没有进行系统的归纳。本文针对新出现的修正方法进行... 卫星光机载荷的光学效能与热设计密切相关,热控系统的模型修正是热设计必不可少的环节。近年国内外涌现出许多基于深度学习和寻优算法的提高热模型修正效率和精确度的方法可供参考,但没有进行系统的归纳。本文针对新出现的修正方法进行了总结,重点分析了在卫星光机载荷热控模型修正这一特殊问题中提高修正效率的几种手段——合适的寻优算法、构建代理模型和开发自动修正工具等。具体分析了这3种手段各自的研究进展及其适用条件和局限性,并提出了对于修正工具开发的思考。最后,对卫星光机载荷热控模型修正领域进行了展望,为后续提高热模型精确度和修正效率提供了方向。 展开更多
关键词 卫星光机载荷 模型修正 代理模型 算法 热设计
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Synthesis of mesoporous polymeric carbon nitride exhibiting enhanced and durable visible light photocatalytic performance 被引量:7
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作者 Fan Dong yuhan li +3 位作者 Wingkei Ho Haidong Zhang Min Fu Zhongbiao Wu 《Chinese Science Bulletin》 SCIE EI CAS 2014年第7期688-698,共11页
A thiourea precursor was employed to synthesize mesoporous carbon nitride(C3 N4) by a thermal polycondensation process with high surface area SiO2 and nanosphere SiO2 as two types of hard templates. The resultant meso... A thiourea precursor was employed to synthesize mesoporous carbon nitride(C3 N4) by a thermal polycondensation process with high surface area SiO2 and nanosphere SiO2 as two types of hard templates. The resultant mesoporous C3 N4 samples have high surface areas(105–112 m2/g) and mesopores with narrow sizes distribution(9.3 nm). Photocatalytic performance was evaluated by removal of NO in air under visible light irradiation. The results showed that mesoporous C3 N4 samples exhibited significantly improved photocatalytic activity in comparison with bulk C3 N4, which also exceeded that of N-doped TiO2 and C-doped TiO2. The activity enhancement can be ascribed to the synergistic effects of large surface area and pore volume, enhanced light-harvesting ability, increased redox potential, and reduced recombination of charge carriers. In addition to the high activity, the mesoporous C3 N4 samples also showed high photochemical stability. The mesoporous C3 N4 photocatalysts with enhanced and durable activity could provide a new efficient material for environmental pollution control. 展开更多
关键词 光催化性能 氮化碳 介孔 高分子 高比表面积 光催化活性 C3N4 耐用
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