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Critical review of biochar for the removal of emerging inorganic pollutants from wastewater 被引量:1
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作者 chong liu Nanthi Bolan +5 位作者 Anushka Upamali Rajapaksha Hailong Wang Paramasivan Balasubramanian Pengyan Zhang Xuan Cuong Nguyen Fayong Li 《Chinese Chemical Letters》 2025年第2期99-107,共9页
Current research primarily focuses on emerging organic pollutants,with limited attention to emerging inorganic pollutants (EIPs).However,due to advances in detection technology and the escalating environmental and hea... Current research primarily focuses on emerging organic pollutants,with limited attention to emerging inorganic pollutants (EIPs).However,due to advances in detection technology and the escalating environmental and health challenges posed by pollution,there is a growing interest in treating waters contaminated with EIPs.This paper explores biochar characteristics and modification methods,encompassing physical,chemical,and biological approaches for adsorbing EIPs.It offers a comprehensive review of research advancements in employing biochar for EIPs remediation in water,outlines the adsorption mechanisms of EIPs by biochar,and presents an environmental and economic analysis.It can be concluded that using biochar for the adsorption of EIPs in wastewater exhibits promising potential.Nonetheless,it is noteworthy that certain EIPs like Au(III),Rh(III),Ir(III),Ru(III),Os(III),Sc(III),and Y(III),have not been extensively investigated regarding their adsorption onto biochar.This comprehensive review will catalyze further inquiry into the biochar-based adsorption of EIPs,addressing current research deficiencies and advancing the practical implementation of biochar as a potent substrate for EIP removal from wastewater streams. 展开更多
关键词 BIOCHAR Emerging inorganic pollutants Adsorption Metal ions Emerging pollutants REMOVAL Emerging contaminants
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Efficient and Stable Perovskite Solar Cells and Modules Enabled by Tailoring Additive Distribution According to the Film Growth Dynamics
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作者 Mengen Ma Cuiling Zhang +5 位作者 Yujiao Ma Weile Li Yao Wang Shaohang Wu chong liu Yaohua Mai 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期387-400,共14页
Gas quenching and vacuum quenching process are widely applied to accelerate solvent volatilization to induce nucleation of perovskites in blade-coating method.In this work,we found these two pre-crystallization proces... Gas quenching and vacuum quenching process are widely applied to accelerate solvent volatilization to induce nucleation of perovskites in blade-coating method.In this work,we found these two pre-crystallization processes lead to different order of crystallization dynamics within the perovskite thin film,resulting in the differences of additive distribution.We then tailor-designed an additive molecule named 1,3-bis(4-methoxyphenyl)thiourea to obtain films with fewer defects and holes at the buried interface,and prepared perovskite solar cells with a certified efficiency of 23.75%.Furthermore,this work also demonstrates an efficiency of 20.18%for the large-area perovskite solar module(PSM)with an aperture area of 60.84 cm^(2).The PSM possesses remarkable continuous operation stability for maximum power point tracking of T_(90)>1000 h in ambient air. 展开更多
关键词 Gas quenching Additive distribution Buried passivation Blade coating Crystallization dynamics
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Photothermal effects of multidimensional confined MMC/TMs-MDCS catalyst for ultra-high photocatalytic hydrogen evolution 被引量:1
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作者 Huihua Luo Haifeng Zhu +4 位作者 Kehui Xue chong liu Nannan Chen Yaping Zhang Lianqing Yu 《Journal of Energy Chemistry》 2025年第5期655-669,共15页
Multidimensional confined structure systems are proposed and demonstrated by using MoO_(2)@MO_(2)C(MMC)to enhance the photothermal catalytic performance of the metal sulfides-multidimensional confined structure(TMs-MD... Multidimensional confined structure systems are proposed and demonstrated by using MoO_(2)@MO_(2)C(MMC)to enhance the photothermal catalytic performance of the metal sulfides-multidimensional confined structure(TMs-MDCS).Specifically,the MMC nanoparticles confined to the surface of the ZnIn_(2)S_(4)hollow tube-shell(MMC/HT-ZIS)achieve a hydrogen evolution rate of 9.72 mmol g^(-1)h^(-1),which is 11.2 times higher than that of pure HT-ZIS.Meanwhile,the MnCdS(MCS)nanoparticles are encapsulated within the two-dimensional MMC(2D MMC/MCS)through precise regulation of size and morphology.The 10-MMC/MCS lamellar network demonstrates the highest hydrogen evolution rate of 8.19 mmol g^(-1)-h^(-1).The obtained MMC/TMs-MDCS catalysts exhibit an enhanced photocatalytic hydrogen evolution rate,which can be attributed to the strong synergistic interaction between the multidimensional confinement and the photothermal effects.The confinement space and the strong interfacial relationship within the MMC/TMs-MDCS create abundant channels and active sites that facilitate electron migration and transport.Furthermore,the construction of a confined environment positions these materials as promising candidates for achieving exceptional photothermal catalytic performance,as MMC/TMs-MDCS enhance light absorption through light scattering and reflecting effects.Additionally,the capacity of MMC/TMsMDCS to convert solar light into thermal energy significantly reduces the activation energy of the reaction,thereby facilitating reaction kinetics and accelerating the separation and transport of photogenerated carriers.This work provides valuable insights for the development of highly efficient photothermal catalytic water-splitting systems for hydrogen production using multidimensional confined catalysts. 展开更多
关键词 Multidimensional confined effect Photothermal effect Photothermal catalytic hydrogen production
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中国的工业化:过去与现在(1887-2017) 被引量:20
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作者 管汉晖 刘冲 辛星 《经济学报》 CSSCI 2020年第3期202-238,共37页
从19世纪60年代第一批现代企业建立至今,中国的工业化经历了一个半世纪。本文首次将历史工业调查数据库和当代工业调查数据库合并,并结合宏观统计数据,研究我国工业化的发展历程及在世界上相对地位的演变。研究发现,我国的工业规模及在... 从19世纪60年代第一批现代企业建立至今,中国的工业化经历了一个半世纪。本文首次将历史工业调查数据库和当代工业调查数据库合并,并结合宏观统计数据,研究我国工业化的发展历程及在世界上相对地位的演变。研究发现,我国的工业规模及在世界工业产值中所占比重都在2011年达到世界第一,目前是世界上工业门类最齐全的国家。工业在总GDP中所占比重1977年超过农业居于第一,并在2003年达到最高(60.11%),此后开始下降,并在2012年被服务业超过,这反映了我国整体产业结构的不断升级;工业总产值中先进制造业所占比重的不断提高也说明了这一点。20世纪以来我国工业区位的分布呈现了从扩散到集聚,再扩散到再集聚的过程,这一特点很大程度上与政府在某些时期对工业化的主导有关,工业部门内部轻重工业相对比重的变化很大程度上也与政府政策有关。工业部门的劳动生产率经历了从1912-1952年的负增长到1952-2017年正增长的转变,体现了我国工业从劳动密集型生产转为资本密集型生产及技术水平的提高。制造业企业的全要素生产率经历了从1933年的较低水平到20世纪80年代至90年代的迅速增长,此后也维持在较高水平,并且在不同时期的不同地区呈现出较大差异。本文的研究结论有助于更好地理解我国的工业化历程,并对下一阶段深入推进新型工业化道路提供一定借鉴。 展开更多
关键词 工业化 经济结构 相对地位 基尼系数 全要素生产率
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Finite Element Analysis of the Influence of End Grouting Defects in Grouted Sleeve on the Structural Performance of Precast Reinforced Concrete Columns
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作者 Shuoting Xiao Nikita Igorevich Fomin +1 位作者 Kirill Anatolyevich Khvostunkov chong liu 《Computer Modeling in Engineering & Sciences》 2025年第12期2821-2847,共27页
Precast concrete structures have gained popularity due to their advantages.However,the seismic performance of their connection joints remains an area of ongoing research and improvement.Grouted Sleeve Connection(GSC)o... Precast concrete structures have gained popularity due to their advantages.However,the seismic performance of their connection joints remains an area of ongoing research and improvement.Grouted Sleeve Connection(GSC)offers a solution for connecting reinforcements in precast components,but their vulnerability to internal defects,such as construction errors and material variability,can significantly impact performance.This article presents a finite element analysis(FEA)to evaluate the impact of internal grouting defects in GSC on the structural performance of precast reinforced concrete columns.Four finite elementmodels representing GSC with varying degrees of defects were used to investigate the effects on mechanical properties,including bearing capacity,stress-deformation behavior,and stiffness degradation.The study highlights the significant impact of internal grouting defects on the mechanical performance of GSC,with findings indicating a decrease in stiffness,increased plastic deformation,and reduced energy dissipation as the proportion of internal defects rises.The analysis reveals that the internal defects in GSC act as stress concentration points,leading to early crack formation and accelerated damage under cyclic loading.By improving construction quality and reducing the prevalence of grouting defects,the adverse effects on the performance of GSC can be mitigated.Compared to defect-free specimens,those with defects of 30%exhibited a 31.23%reduction in horizontal bearing capacity,highlighting the importance of minimizing defects in practical engineering applications. 展开更多
关键词 Precast concrete structures column grouted sleeve connections(GSC) seismic performance internal defects finite element analysis(FEA) mechanical properties
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泪小点栓塞术对中度混合型干眼的疗效观察 被引量:4
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作者 刘翀 肖启国 +1 位作者 刘辉 成喆 《中国现代医学杂志》 CAS 北大核心 2017年第16期58-61,共4页
目的观察泪小点栓塞术对中度混合型干眼患者眼部症状体征及炎症因子的影响,评价泪小点栓塞术对中度混合型干眼的疗效。方法对中度混合型干眼患者行泪小点栓塞术。对患者术前、术后30和60 d的OSDI评分、泪膜破裂时间(TBUT)、泪液分泌实验... 目的观察泪小点栓塞术对中度混合型干眼患者眼部症状体征及炎症因子的影响,评价泪小点栓塞术对中度混合型干眼的疗效。方法对中度混合型干眼患者行泪小点栓塞术。对患者术前、术后30和60 d的OSDI评分、泪膜破裂时间(TBUT)、泪液分泌实验(未表面麻醉的Schirmer I)以及角膜荧光染色评分进行评估,并且测量泪液中炎症因子IL-1β、金属蛋白酶9(MMP-9)及TNF-α的表达,比较上述指标的变化。结果34例(68眼)中度混合型干眼患者术后与术前相比,干眼患者OSDI评分、角膜荧光染色评分下降,差异有统计学意义(P<0.05);而泪液分泌实验、泪膜破裂时间差异无统计学意义(P>0.05);泪液中炎症因子IL-1β,MMP-9及TNF-α的水平均出现了不同程度的降低,差异有统计学意义(P<0.05)。结论泪小点栓塞术能改善中度混合型干眼患者的眼部症状体征,降低眼表炎症因子的水平。 展开更多
关键词 中度 混合型干眼 泪小点栓塞术 炎症因子
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Synergistic effect between nitrogen-doped sites and metal chloride for carbon supported extra-low mercury catalysts in acetylene hydrochlorination
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作者 Yiyang Qiu chong liu +4 位作者 Xueting Meng Yuesen liu Jiangtao Fan Guojun Lan Ying Li 《Chinese Journal of Chemical Engineering》 2025年第3期145-154,共10页
Carbon-supported mercury catalysts are extensivelyemployed in calcium carbide-based polyvinyl chloride(PVC)industries,but the usage of mercury-based catalysts can pose an environmental threat due to the release of mer... Carbon-supported mercury catalysts are extensivelyemployed in calcium carbide-based polyvinyl chloride(PVC)industries,but the usage of mercury-based catalysts can pose an environmental threat due to the release of mercury into the surrounding area during the operation period.In this study,a highly active and stable mercury-based catalyst was developed,utilizing the nitrogen atom of the support as the anchor site to enhance the interaction between active sites(HgCl_(2))and the carbon support(N-AC).Thermal loss rate testing and thermogravimetric analysis results demonstrate that,compared to commercial activated carbon,N-doped carbon can effectively increase the heat stability of HgCl_(2).The obtained mercury-based catalysts(HgCl_(2)/N-AC)exhibit significant catalytic performance,achieving 2.5 times the C2H2 conversion of conventional HgCl_(2)/AC catalysts.Experimental analysis combined with theoretical calculations reveals that,contrary to the Eley-Rideal(ER)mechanism of HgCl_(2)/AC,the HgCl_(2)/N-AC catalyst follows the Langmuir-Hinshelwood(LH)adsorption mechanism.The nitrogen sites and HgCl_(2) on the catalyst enhance the adsorption capabilities of the HCl and C2H2,thereby improving the catalytic performance.Based on the modification of the active center by these solid ligands,the loading amount of HgCl_(2) on the catalyst can be further reduced from the current 6.5%to 3%.Considering the absence of successful industrial applications for mercury-free catalysts,and based on the current annual consumption of commercial mercury chloride catalysts in the PVC industry,the widespread adoption of this technology could annually reduce the usage of chlorine mercury by 500 tons,making a notable contribution to mercury compliance,reduction,and emissions control in China.It also serves as a bridge between mercury-free and low-mercury catalysts.Moreover,this solid ligand technology can assist in the application research of mercury-free catalysts. 展开更多
关键词 Acetylene hydrochlorination Activated carbon Catalyst support Mercury catalyst DFT calculation KINETICS
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Design and Characterization of Bionic Lymphatic Valve Based on Thin Film Shell Theory
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作者 Lixia Yang Shaohua Zuo +5 位作者 Wenhao Yin Emad Uddin Li Chen Zhongyang Peng chong liu Jingmin Li 《Journal of Bionic Engineering》 2025年第4期1819-1833,共15页
The unidirectional flow of lymphatic fluid depends significantly on the valve structure within the lymphatic system,thus impacting tumor cell metastasis via the lymphatic system.However,existing microdevices for study... The unidirectional flow of lymphatic fluid depends significantly on the valve structure within the lymphatic system,thus impacting tumor cell metastasis via the lymphatic system.However,existing microdevices for studying tumor lymphatic metastasis have overlooked the impact of open-close valve structures on the lymphatic flow field.This paper presents a novel biomimetic lymphatic valve structure,which innovatively incorporates the thin-shell theory into the modeling of lymphatic-mimicking structures.Through finite element simulations,we have systematically analyzed the influence of valve thickness and elasticity on its deformation characteristics.Materials closely matching the actual properties of biological tissues are synthesized.And the soft-etching technique was used to fabricate lymphomimetic microchannels,which were then tested to evaluate their capability in intercepting unidirectional flow.The results showed that the lymphomimetic valve structure had no observable leaks and effectively intercepted unidirectional flow.Our study not only elucidates the mechanism of lymphatic circulation but also presents a dependable biomimetic model that could facilitate additional biological investigations and phenotypic drug screening. 展开更多
关键词 BIONIC Thin Film Shell Theory Lymphatic Valves Microfluidic Chip Soft Etching Tumor Microenvironment
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The study of antibacterial activity of cationic poly(β-amino ester)regulating by amphiphilic balance
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作者 chong liu Ling Li +7 位作者 Jiahui Gao Yanwei Li Nazhen Zhang Jing Zang Cong liu Zhaopei Guo Yanhui Li Huayu Tian 《Chinese Chemical Letters》 2025年第2期304-308,共5页
It is well known that cationic polymers have excellent antimicrobial capacity accompanied with high biotoxicity,to reduce biotoxicity needs to decrease the number of cationic groups on polymers,which will influence an... It is well known that cationic polymers have excellent antimicrobial capacity accompanied with high biotoxicity,to reduce biotoxicity needs to decrease the number of cationic groups on polymers,which will influence antimicrobial activity.It is necessary to design a cationic polymer mimic natural antimicrobial peptide with excellent antibacterial activity and low toxicity to solve the above dilemma.Here,we designed and prepared a series of cationic poly(β-amino ester)s(PBAEs)with different cationic contents,and introducing hydrophobic alkyl chain to adjust the balance between antimicrobial activity and biotoxicity to obtain an ideal antimicrobial polymer.The optimum one of synthesized PBAE(hydrophilic cationic monomer:hydrophobic monomer=5:5)was screened by testing cytotoxicity and minimum inhibitory concentration(MIC),which can effectively kill S.aureus and E.coli with PBAE concentration of15μg/m L by a spread plate bacteriostatic method and dead and alive staining test.The way of PBAE killing bacterial was destroying the membrane like natural antimicrobial peptide observed by scanning electron microscopy(SEM).In addition,PBAE did not exhibit hemolysis and cytotoxicity.In particular,from the result of animal tests,the PBAE was able to promote healing of infected wounds from removing mature S.aureus and E.coli on the surface of infected wound.As a result,our work offers a viable approach for designing antimicrobial materials,highlighting the significant potential of PBAE polymers in the field of biomedical materials. 展开更多
关键词 Antimicrobial Cationic polymers Poly(β-amino ester)s Michael addition polymerization Amphiphilic balance
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Baseline establishment,susceptibility monitoring and risk assessment of cyproflanilide,a novel meta-diamide insecticide,against Chilo suppressalis(Lepidoptera:Crambidae)in China
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作者 Wenchao Ge Songtao Qiao +7 位作者 chong liu Fangrui Guo Shuai Wang Hao Sun Yan liu Fengxia Yang Shunfan Wu Congfen Gao 《Journal of Integrative Agriculture》 2025年第11期4342-4354,共13页
The rice stem borer,Chilo suppressalis(Walker)(Lepidoptera:Crambidae),is one of the most serious pests in rice-growing areas,and it has developed resistance to most insecticides currently used in the field.Cyproflanil... The rice stem borer,Chilo suppressalis(Walker)(Lepidoptera:Crambidae),is one of the most serious pests in rice-growing areas,and it has developed resistance to most insecticides currently used in the field.Cyproflanilide is a novel meta-diamide insecticide that has shown high activities to multiple pests.Evaluating the risk of resistance to cyproflanilide in C.suppressalis is necessary for its preventive resistance management.Here we established the baseline susceptibility of C.suppressalis to cyproflanilide by the rice-seedling dipping method and topical application,and the LC_(50) and LD_(50) values were 0.026 mg L^(-1) and 0.122 ng/larva,respectively.The LC_(50) values of cyproflanilide in 37 field populations ranged from 0.012 to 0.061 mg L^(-1),and 25 field populations exhibited resistance to chlorantraniliprole with the highest LC_(50) value of 3,770.059 mg L^(-1).In addition,a logistic distribution model analysis indicated that only 0.048 mg L^(-1) of cyproflanilide was required to kill 90% field chlorantraniliprole-resistant populations of C.suppressalis,compared to 2,087.764 mg L^(-1) of chlorantraniliprole for a similar level of control.Resistance screening over 19 generations did not result in resistance to cyproflanilide(RR=3.1-fold).The realized heritability(h^(2))of resistance was estimated as 0.067 by using threshold trait analysis,suggesting a low risk of cyproflanilide resistance development in susceptible strains.The Cypro-SEL population(F_(10))had no obvious fitness cost(relative fitness=0.96),and no significant changes in sensitivity to seven tested insecticides.These findings suggested that cyproflanilide is a promising insecticide for the management of chlorantraniliprole-resistant C.suppressalis.Moreover,this integrated risk assessment provides scientific application guidelines for the sustainable resistance management of cyproflanilide for controlling C.suppressalis. 展开更多
关键词 cyproflanilide Chilo suppressalis susceptibility baseline risk assessment realized heritability
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Comprehensive review of synthesis strategies and performance enhancement of metal-organic frameworks and their derivatives for photocatalytic applications
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作者 Huihua Luo Lianqing Yu +5 位作者 chong liu Nannan Chen Kehui Xue Wendi liu Haifeng Zhu Yaping Zhang 《Journal of Energy Chemistry》 2025年第4期408-439,共32页
Energy conversion and environmental pollution present significant challenges that necessitate the development of materials with optimal characteristics for effective applications in solar energy-driven photocatalysis.... Energy conversion and environmental pollution present significant challenges that necessitate the development of materials with optimal characteristics for effective applications in solar energy-driven photocatalysis.Metal-organic frameworks(MOFs)serve as excellent platforms for the development of various MOF-derived materials,which have garnered extensive attention due to their unique structural features,high crystallinity,large surface areas,diverse morphologies,adjustable dimensions,tunable textural characteristics,and inherent catalytic activity.However,the sluggish charge kinetics and poor stability of MOFs and MOF-derived photocatalysts restrict their photocatalytic activity,thereby limiting their applications in the field of photocatalysis.Consequently,substantial research efforts have been directed toward maximizing the advantages of these intriguing materials while addressing their shortcomings.This review provides a comprehensive summary and analysis of various synthesis strategies of MOFs and their derivatives.Effective modification strategies to enhance the performance of these novel materials are also summarized.This review systematically explores the current advancements in the application of MOFs and their derivatives for photocatalytic water splitting,photocatalytic CO_(2)reduction,and environmental water pollution treatment.Finally,it discusses the challenges and future prospects of MOFs and MOF-derived materials in photocatalytic applications.Researchers should systematically optimize synthetic strategies and functionalize MOFs and their derivatives to enhance their application in energy conversion and environmental pollution control,thereby underscoring their extensive potential.Future research will increasingly concentrate on the intelligent design and functionalization of MOFs to attain superior catalytic performance and tackle the urgent energy and environmental challenges confronting the world. 展开更多
关键词 Metal-organic frameworks DERIVATIVES Energy convention Environmental pollution
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A Review on High-Efficiency Transfer of Graphene Films Free from Defects and Contamination
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作者 Wenhao Yin chong liu Jingmin Li 《Energy & Environmental Materials》 2025年第4期227-242,共16页
Graphene,owing to its exceptional electronic,optical,thermal,and mechanical properties,has emerged as a highly promising material.Currently,the synthesis of large-area graphene films on metal substrates via chemical v... Graphene,owing to its exceptional electronic,optical,thermal,and mechanical properties,has emerged as a highly promising material.Currently,the synthesis of large-area graphene films on metal substrates via chemical vapor deposition remains the predominant approach for producing high-quality graphene.To realize the potential applications of graphene,it is essential to transfer graphene films to target substrates in a manner that is non-destructive,clean,and efficient,as this significantly affects the performance of graphene devices.This review examines the current methods for graphene transfer from three perspectives:non-destructive transfer,clean transfer,and high-efficiency transfer.It analyzes and compares the advancements and limitations of various transfer techniques.Finally,the review identifies the key challenges faced by current graphene transfer methods and anticipates future developmental prospects. 展开更多
关键词 clean transfer defect-free transfer high-efficiency transfer of graphene
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Dark-bright solitons and the role of their interaction in breather generation
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作者 Le Li Wen-Juan Che +2 位作者 Xi-Zhe liu chong liu Nail Akhmediev 《Communications in Theoretical Physics》 2025年第4期12-22,共11页
We study fundamental dark-bright solitons and the interaction of vector nonlinear Schr?dinger equations in both focusing and defocusing regimes.Classification of possible types of soliton solutions is given.There are ... We study fundamental dark-bright solitons and the interaction of vector nonlinear Schr?dinger equations in both focusing and defocusing regimes.Classification of possible types of soliton solutions is given.There are two types of solitons in the defocusing case and four types of solitons in the focusing case.The number of possible variations of two-soliton solutions depends on this classification.We demonstrate that only special types of two-soliton solutions in the focusing regime can generate breathers of the scalar nonlinear Schr?dinger equation.The cases of solitons with equal and unequal velocities in the superposition are considered.Numerical simulations confirm the validity of our exact solutions. 展开更多
关键词 Manakov equations Dark-bright solitons BREATHERS
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风动还是帆动:银监局局长更替与城商行策略性信息披露 被引量:4
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作者 郭峰 刘冲 《金融学季刊》 CSSCI 2016年第3期85-106,共22页
准确获取银行经营信息对监管者维护金融稳定和增进市场效率具有重要意义,但银行可能会利用会计自由裁量权进行策略性信息披露。银监局局长变更导致的“责任空档期”为识别银行策略性信息披露行为创造了条件。本文利用2004--2013年110余... 准确获取银行经营信息对监管者维护金融稳定和增进市场效率具有重要意义,但银行可能会利用会计自由裁量权进行策略性信息披露。银监局局长变更导致的“责任空档期”为识别银行策略性信息披露行为创造了条件。本文利用2004--2013年110余家城市商业银行(以下简称城商行)与省级银监局局长更替的匹配数据,实证发现银监局局长变更时,城商行不良贷款率显著高于其他时期,而关注类贷款比例则呈反方向变动。进一步回归并没有发现银监局局长变更伴随着银行风险资产配置的增加或银行破产风险状况的恶化。银行利用银监局局长变更导致的责任空档期,将之前通过会计自由裁量权隐藏的不良贷款集中释放出来,策略性信息披露行为得到验证。多个稳健性分析表明本文的结论具有较好的稳健性。 展开更多
关键词 金融监管 官员变更 城市商业银行 会计自由裁量 策略性信息披露
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断点回归设计:理论前沿进展与新应用场景 被引量:10
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作者 刘冲 诸宇灵 李皓宇 《经济学报》 CSSCI 2022年第3期325-366,共42页
近年来,作为最重要的准实验方法之一,断点回归设计(RDD)在经济学研究中的重要性不仅体现在应用实践中的快速发展,更体现在一系列前沿理论的突破与完善。本文系统梳理了连续性和局部随机性两种断点回归设计的分析框架,总结了两种框架的... 近年来,作为最重要的准实验方法之一,断点回归设计(RDD)在经济学研究中的重要性不仅体现在应用实践中的快速发展,更体现在一系列前沿理论的突破与完善。本文系统梳理了连续性和局部随机性两种断点回归设计的分析框架,总结了两种框架的关键假设、估计方法、统计推断、实现方式及主要操作步骤,在此基础上对比了两者在理论和应用场景方面的差异。本文进一步阐述了多重配置变量、多重断点和拐点回归设计等三种特殊情形下的RDD估计方法,并提供了具体的实现方式,为丰富RDD方法的应用场景、拓展实证研究的可行性提供了有力支撑。 展开更多
关键词 断点回归设计 连续性框架 局部随机性框架 理论进展 应用场景
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肠碱性磷酸酶在肠黏膜屏障中的作用 被引量:3
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作者 万军 田忠 +4 位作者 姚柏宇 刘翀 何静妮 殷鑫 史旸 《世界华人消化杂志》 CAS 2019年第23期1441-1445,共5页
肠碱性磷酸酶(intestinal alkaline phosphatase,IAP)是一种碱性磷酸酶,在维持肠黏膜屏障的稳定和肠道功能具有重要作用,其中包括调节十二指肠pH、反映肠道的发育情况及小肠上皮细胞的吸收能力,降低肠道脂多糖毒力、预防和减少肠道炎症... 肠碱性磷酸酶(intestinal alkaline phosphatase,IAP)是一种碱性磷酸酶,在维持肠黏膜屏障的稳定和肠道功能具有重要作用,其中包括调节十二指肠pH、反映肠道的发育情况及小肠上皮细胞的吸收能力,降低肠道脂多糖毒力、预防和减少肠道炎症、调节肠道菌群分布、抑制细菌位移、改善肠道钙吸收等功能.本文对近年来IAP在肠黏膜屏障中的作用研究进展做一综述. 展开更多
关键词 肠碱性磷酸酶 肠黏膜屏障 综述文献
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基于乙烯基砜表面构建双向密度梯度的通用策略及其在生物检测芯片制备的研究 被引量:1
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作者 刘冲 程昉 何炜 《高分子学报》 SCIE CAS CSCD 北大核心 2023年第9期1320-1332,共13页
报道了一种基于乙烯基砜(VS)表面的双向密度梯度构建的新策略,该策略能够在生物配体梯度表面上直接生长惰性聚合物刷而不需要额外的表面改性.采用该策略制备明确的配体密度芯片可用于在复杂生物流体中对应抗体的高特异性检测.选择荧光... 报道了一种基于乙烯基砜(VS)表面的双向密度梯度构建的新策略,该策略能够在生物配体梯度表面上直接生长惰性聚合物刷而不需要额外的表面改性.采用该策略制备明确的配体密度芯片可用于在复杂生物流体中对应抗体的高特异性检测.选择荧光素作为小分子活性配体模型以发展和验证该策略.采用该策略制备荧光素和两性离子聚合物刷组成的双向密度梯度样品,并通过荧光素抗体(anti-FITC)在样品表面的皮尔森系数优选出聚甲基丙烯酸磺基甜菜碱(PSBMA)作为惰性配体.该双向密度梯度样品对anti-FITC和牛血清白蛋白(BSA)分别具有良好的特异性和抗非特异性结合能力.通过该策略制备了具有明确anti-FITC吸附性能的荧光素芯片,发现高密度荧光素芯片在BSA和50%胎牛血清(FBS)溶液中对anti-FITC具有高的特异性和敏感性.此外,选择抗人绒毛膜促性腺激素抗体(anti-HCG)和抗β2-微球蛋白抗体(anti-BMG)作为生物大分子模型验证该策略的通用性.因此,该策略不仅可以作为双向密度梯度制备的通用方法,而且可为生物检测芯片的制备提供理论指导. 展开更多
关键词 双向密度梯度 乙烯基砜表面 荧光素 聚甲基丙烯酸磺基甜菜碱
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二维黑磷基纳米材料在光催化中的应用 被引量:5
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作者 庞欣 薛世翔 +3 位作者 周彤 袁蝴蝶 刘冲 雷琬莹 《化学进展》 SCIE CAS CSCD 北大核心 2022年第3期630-642,共13页
黑磷是继石墨烯之后又一种新型的单元素二维材料。具有独特的层状结构、超高的载流子迁移率和由层厚调控的禁带宽度,在光催化领域具有广阔的应用前景。然而,单一黑磷材料的禁带宽度较窄(≤1.5 eV),光生载流子极易复合,导致其光催化性能... 黑磷是继石墨烯之后又一种新型的单元素二维材料。具有独特的层状结构、超高的载流子迁移率和由层厚调控的禁带宽度,在光催化领域具有广阔的应用前景。然而,单一黑磷材料的禁带宽度较窄(≤1.5 eV),光生载流子极易复合,导致其光催化性能较低。另外,黑磷表面的磷原子易与环境中的氧气发生反应形成P_(x)O_(y),降低了黑磷材料的稳定性。因此,较低的催化性能和不稳定性极大地限制了黑磷材料的实际应用。针对上述问题,可以通过将黑磷材料与其他材料复合形成一系列的等离子体复合材料和多维异质结的方式,来提高光催化剂的活性和循环稳定性。本文综述了近年来二维黑磷纳米片与金属、半导体和碳材料等复合后形成的复合材料在光催化裂解水产氢、降解有机污染物、CO_(2)还原和固氮等方面的研究进展。最后,对未来二维黑磷基光催化材料的研究方向进行了分析和展望。 展开更多
关键词 黑磷基复合材料 光催化 裂解水产氢 降解有机污染物 CO_(2)还原 固氮
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做市商制度促进股票流动性了吗?——来自新三板市场的证据 被引量:6
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作者 赵崇博 刘冲 钱留杰 《经济学报》 CSSCI 2019年第4期78-101,共24页
本文以2014年8月新三板引入做市商制度为拟自然实验,结合2014—2017年新三板挂牌公司数据,采用双重差分法检验了交易方式转变对股票流动性的影响。研究发现,从交易笔数、交易规模、换手率、价格冲击指标和价差等多个维度看,交易方式由... 本文以2014年8月新三板引入做市商制度为拟自然实验,结合2014—2017年新三板挂牌公司数据,采用双重差分法检验了交易方式转变对股票流动性的影响。研究发现,从交易笔数、交易规模、换手率、价格冲击指标和价差等多个维度看,交易方式由协议转让转变为做市转让,均能显著提升公司股票流动性。上述结论在交易数据剔除大宗交易订单后依然稳健。进一步异质性分析表明,在交易方式转变后,初始流动性越差,公司股票流动性提升越明显;主办券商获取库存股的折价率越低,股票流动性提升也越明显。从机制角度分析,做市商制度一方面通过提升个人投资者的活跃度,提升了做市企业的流动性;另一方面通过缓解价格波动,稳定市场价格,带来流动性的改善。 展开更多
关键词 做市转让 协议转让 做市商 股票流动性 大宗交易
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强大国内市场与经济增长极培育--基于市场一体化视角的分析 被引量:7
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作者 刘晨冉 刘冲 牛逸婕 《产业经济评论》 CSSCI 2021年第4期73-88,共16页
利用高速公路“国道主干线系统”这一准自然实验,本文在市场一体化视角下检验了交通基础设施建设对产业集聚的影响,诠释了强大的国内市场有助于经济增长极的培育。我们借鉴Baum-Snow等(2016)的方法构建了地级市层面的市场可达性指标,全... 利用高速公路“国道主干线系统”这一准自然实验,本文在市场一体化视角下检验了交通基础设施建设对产业集聚的影响,诠释了强大的国内市场有助于经济增长极的培育。我们借鉴Baum-Snow等(2016)的方法构建了地级市层面的市场可达性指标,全面地反映了交通基础设施发展对国内市场一体化程度的提升作用。基于1998-2007年地级市-二位数制造业行业维度的面板数据,本文发现市场一体化显著提升了地区和行业上经济活动的集聚程度。我们还发现这种促进作用在中部地区和轻工业行业中较为明显,在更具比较优势、区内基建基础更好的地区更加突出。进一步的分析发现,市场一体化还带来了企业创新活动的增加。 展开更多
关键词 交通基础设施 市场一体化 产业集聚 经济增长极
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