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Interfacial Superconductivity in the Type-Ⅲ Heterostructure SnSe_(2)/PtTe_(2)
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作者 jun fan Xiao-Le Qiu +2 位作者 Ben-Chao Gong Kai Liu Zhong-Yi Lu 《Chinese Physics Letters》 2026年第1期248-264,共17页
Interfacial superconductivity(IS)has been a topic of intense interest in condensed matter physics,due to its unique properties and exotic photoelectrical performance.However,there are few reports about IS systems cons... Interfacial superconductivity(IS)has been a topic of intense interest in condensed matter physics,due to its unique properties and exotic photoelectrical performance.However,there are few reports about IS systems consisting of two insulators.Here,motivated by the emergence of an insulator-metal transition in type-Ⅲ heterostructures and the superconductivity in some“special”two-dimensional(2D)semiconductors via electron doping,we predict that the 2D heterostructure SnSe_(2)/PtTe_(2) is a model system for realizing IS by using firstprinciples calculations.Our results show that due to slight but crucial interlayer charge transfer,SnSe_(2)/PtTe_(2) turns to be a type-Ⅲ heterostructure with metallic properties and shows a superconducting transition with the critical temperature(T_(c))of 3.73 K.Similar to the enhanced electron–phonon coupling(EPC)in the electrondoped SnSe_(2) monolayer,the IS in the SnSe_(2)/PtTe_(2) heterostructure mainly originates from the metallized SnSe_(2) layer.Furthermore,we find that its superconductivity is sensitive to tensile lattice strain,forming a domeshaped superconducting phase diagram.Remarkably,at 7%biaxial tensile strain,the superconducting T_(c) can increase more than twofold(8.80 K),resulting from softened acoustic phonons at the𝑀point and enhanced EPC strength.Our study provides a concrete example for realizing IS in type-Ⅲ heterostructures,which waits for future experimental verification. 展开更多
关键词 d heterostructure condensed matter type III heterostructure PtTe interfacial superconductivity SnSe electron dopingwe first principles calculations
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Novel S‐scheme 2D/2D BiOBr/g‐C_(3)N_(4)heterojunctions with enhanced photocatalytic activity 被引量:25
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作者 Bin Zhang Xiaoyun Hu +1 位作者 Enzhou Liu jun fan 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第9期1519-1529,共11页
The design and construction of heterojunction photocatalysts,which possess a staggered energy band structure and appropriate interfacial contact,is an effective way to achieve outstanding photocatalytic performance.In... The design and construction of heterojunction photocatalysts,which possess a staggered energy band structure and appropriate interfacial contact,is an effective way to achieve outstanding photocatalytic performance.In this study,2D/2D BiOBr/g‐C_(3)N_(4)heterojunctions were successfully obtained by a convenient in situ self‐assembly route.Under simulated sunlight irradiation,99%of RhB(10 mg·L–1,100 mL)was efficiently degraded by 1.5‐BiOBr/g‐C_(3)N_(4)within 30 min,which is better than the performance of both BiOBr and g‐C_(3)N_(4),and it has superior stability.In addition,the composite also exhibits enhanced photocatalytic activity for H2 production.The enhanced activity can be attributed to the intimate interface contact,the larger surface area,and the highly efficient separation of photoinduced electron–hole pairs.Based on the experimental results,a novel S‐scheme model was proposed to illuminate the transfer process of charge carriers.This study presents a simple way to develop novel step‐scheme photocatalysts for environmental and related applications. 展开更多
关键词 BiOBr/g‐C_(3)N_(4) 2D/2D Photocatalytic RhB degradation H_(2)evolution S‐scheme heterojunction
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Enhanced photocatalytic H_2 production over dual-cocatalyst-modified g-C_3N_4 heterojunctions 被引量:8
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作者 Zong Li Yongning Ma +2 位作者 Xiaoyun Hu Enzhou Liu jun fan 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第3期434-445,共12页
Ag nanoparticles (NPs) were deposited on the surface of g-C3N4 (CN) by an in situ calcination method. NiS was successfully loaded onto the composites by a hydrothermal method. The results showed that the 10 wt%-NiS/1.... Ag nanoparticles (NPs) were deposited on the surface of g-C3N4 (CN) by an in situ calcination method. NiS was successfully loaded onto the composites by a hydrothermal method. The results showed that the 10 wt%-NiS/1.0 wt%-Ag/CN composite exhibits excellent photocatalytic H2 generation performance under solar-light irradiation. An H2 production rate of 9.728 mmol·g^-1·h^-1 was achieved, which is 10.82-, 3.45-, and 2.77-times higher than those of pure g-C3N4, 10 wt%-NiS/CN, and 1.0 wt%-Ag/CN composites, respectively. This enhanced photocatalytic H2 generation can be ascribed to the co-decoration of Ag and NiS on the surface of g-C3N4, which efficiently improves light harvesting capacity, photogenerated charge carrier separation, and photocatalytic H2 production kinetics. Thus, this study demonstrates an effective strategy for constructing excellent g-C3N4-related composite photocatalysts for H2 production by using different co-catalysts. 展开更多
关键词 PHOTOCATALYSIS Photocatalytic H2 generation g-C3N4 Ag NIS
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S-scheme regulated Ni_(2)P-NiS/twinned Mn_(0.5)Cd_(0.5)S hetero-homojunctions for efficient photocatalytic H_(2)evolution 被引量:4
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作者 Qiqi Zhang Zhen Wang +3 位作者 Yuhang Song jun fan Tao Sun Enzhou Liu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第2期148-157,共10页
Effective bulk phase and surface charge separation is critical for charge utilization during the photo-catalytic energy conversion process.In this work,the ternary Ni_(2)P-NiS/twinned Mn_(0.5)Cd_(0.5)S(T-MCS)nanohybri... Effective bulk phase and surface charge separation is critical for charge utilization during the photo-catalytic energy conversion process.In this work,the ternary Ni_(2)P-NiS/twinned Mn_(0.5)Cd_(0.5)S(T-MCS)nanohybrids were successfully constructed via combining Ni_(2)P-NiS with T-MCS solid solution for visible light photocatalytic H_(2)evolution.T-MCS is composed of zinc blende Mn_(0.5)Cd_(0.5)S(ZB-MCS)and wurtzite Mn_(0.5)Cd_(0.5)S(WZ-MCS)and those two alternatively arranged crystal phases endow T-MCS with excellent bulk phase charge separation performance for the slight energy level difference between ZB-MCS and WZ-MCS.S-scheme carriers transfer route between NiS and T-MCS can accelerate the interfacial charge separation and retain the active electrons and holes,meanwhile,co-catalyst Ni_(2)P as electron receiver and proton reduction center can further optimize the H_(2)evolution reaction kinetics based on the surface Schottky barrier effect.The above-formed homo-heterojunctions can establish multiple charge transfer channels in the bulk phase of T-MCS and interface of T-MCS and Ni_(2)P-NiS.Under the synergistic effect of twinned homojunction,S-scheme heterojunction,and Schottky barrier,the ternary Ni_(2)P-NiS/T-MCS com-posite manifested an H_(2)production rate of 122.5 mmol h^(-1)g^(-1),which was 1.33,1.24,and 2.58 times higher than those of the NiS/T-MCS(92.4 mmol h^(-1)g^(-1)),Ni_(2)P/T-MCS(98.4 mmol h^(-1)g^(-1)),and T-MCS(47.5 mmol h^(-1)g^(-1)),respectively.This work demonstrates a promising strategy to develop efficient sul-fides photocatalyst toward targeted solar-driven H_(2)evolution through homo-heterojunction engineering. 展开更多
关键词 Photocatalytic H_(2)evolution Twinned Mn_(0.5)Cd_(0.5)S Homojunction S-scheme heterojunction Schottky barrier
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Bi_(2)WO_(6)/AgInS_(2)S-scheme heterojunction:Efficient photodegradation of organic pollutant and toxicity evaluation 被引量:3
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作者 Yanyan Zhao Xu fan +3 位作者 Hongxing Zheng Enzhou Liu jun fan Xuejun Wang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第3期200-211,共12页
Constructing of heterojunction was identified as a feasible way to improve photocatalytic activity of pho-tocatalyst.In this work,a n-p type Bi_(2)WO_(6)/AgInS_(2)S-scheme heterojunction was successfully prepared for ... Constructing of heterojunction was identified as a feasible way to improve photocatalytic activity of pho-tocatalyst.In this work,a n-p type Bi_(2)WO_(6)/AgInS_(2)S-scheme heterojunction was successfully prepared for organic pollutants degradation.This Bi_(2)WO_(6)/AgInS_(2)S-scheme heterojunction exhibited much higher pho-tocatalytic activity towards Rhodamine B(92.24%,expose to visible light for 60 min),norfloxacin(81.73%,expose to visible light for 90 min)and levofloxacin(87.46%,expose to visible light for 90 min)than pure Bi_(2)WO_(6)and pure AgInS_(2).Toxicity analysis indicated the low environmental toxicity of Rhodamine B degradation intermediates for Rye seeds and Sudangrass seeds germination and growth.Mechanism study displayed that AgInS_(2)and Bi_(2)WO_(6)work as the primary photocatalyst to form·O_(2)−and ·OH,respectively.The improved photocatalytic activity of the Bi_(2)WO_(6)/AgInS_(2)S-scheme heterojunction was due to the im-proved light response range and intensified carrier separation capability.Additionally,a S-scheme charge transfer mechanism including multiple charge transfer channels was proposed.This work could provide an effective strategy for organic pollutants degradation in wastewater. 展开更多
关键词 Photocatalysis S-scheme heterojunction AgInS_(2) Bi_(2)WO_(6) Toxicity experiments
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S-型MnCo_(2)S_(4)/g-C_(3)N_(4)异质结光催化产氢性能研究 被引量:10
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作者 孙涛 李晨曦 +2 位作者 鲍钰鹏 樊君 刘恩周 《物理化学学报》 SCIE CAS CSCD 北大核心 2023年第6期112-121,共10页
本文通过简单的水热法和热解法分别得到MnCo_(2)S_(4)和g-C_(3)N_(4)催化剂,之后采用溶剂蒸发法将MnCo_(2)S_(4)和g-C_(3)N_(4)纳米片结合构建获得无贵金属的S-型MnCo_(2)S_(4)/g-C_(3)N_(4)异质结。研究结果表明,优化后的复合材料具有... 本文通过简单的水热法和热解法分别得到MnCo_(2)S_(4)和g-C_(3)N_(4)催化剂,之后采用溶剂蒸发法将MnCo_(2)S_(4)和g-C_(3)N_(4)纳米片结合构建获得无贵金属的S-型MnCo_(2)S_(4)/g-C_(3)N_(4)异质结。研究结果表明,优化后的复合材料具有良好的光催化产氢活性,其产氢速率最高可到2979μmol·g^(-1)·h^(-1),分别为g-C_(3)N_(4)(113μmol·g^(-1)·h^(-1))和MnCo_(2)S_(4)(341μmol·g^(-1)·h^(-1))的26.4和8.7倍。这主要归因于形成的S-型异质结具有比单体更低的反应阻抗,更高的光电流和高效的电子-空穴分离能力,以及低的析氢过电势。本研究为开发稳定、高效的非贵金属产氢异质结催化剂提供了实验基础。 展开更多
关键词 MnCo_(2)S_(4) g-C_(3)N_(4) S-型异质结 光催化分解水
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Machine learning accelerated catalysts design for CO reduction:An interpretability and transferability analysis
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作者 Yuhang Wang Yaqin Zhang +4 位作者 Ninggui Ma jun Zhao Yu Xiong Shuang Luo jun fan 《Journal of Materials Science & Technology》 2025年第10期14-23,共10页
Developing machine learning frameworks with predictive power,interpretability,and transferability is crucial,yet it faces challenges in the field of electrocatalysis.To achieve this,we employed rigorous feature engine... Developing machine learning frameworks with predictive power,interpretability,and transferability is crucial,yet it faces challenges in the field of electrocatalysis.To achieve this,we employed rigorous feature engineering to establish a finely tuned gradient boosting regressor(GBR)model,which adeptly captures the physical complexity from feature space to target variables.We demonstrated that environmental electron effects and atomic number significantly govern the success of the mapping process via global and local explanations.The finely tuned GBR model exhibits exceptional robustness in predicting CO adsorption energies(R_(ave)^(2)=0.937,RMSE=0.153 eV).Moreover,the model demonstrated remarkable transfer learning ability,showing excellent predictive power for OH,NO,and N_(2) adsorption.Importantly,the GBR model exhibits exceptional predictive capability across an extensive search space,thereby demonstrating profound adaptability and versatility.Our research framework significantly enhances the interpretability and transferability of machine learning in electrocatalysis,offering vital insights for further advancements. 展开更多
关键词 Machine learning First-principles calculation INTERPRETABILITY Transferability CO reduction
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Ni_(2)P-NiS双助剂促进g-C_(3)N_(4)光催化产氢动力学 被引量:10
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作者 雷卓楠 马心怡 +2 位作者 胡晓云 樊君 刘恩周 《物理化学学报》 SCIE CAS CSCD 北大核心 2022年第7期36-44,共9页
本文通过简单的一步水热法得到Ni_(2)P-NiS双助催化剂,之后采用溶剂蒸发法将Ni_(2)P-NiS与g-C_(3)N_(4)纳米片结合构建获得无贵金属的Ni_(2)P-NiS/g-C_(3)N_(4)异质结。研究结果表明,优化后的复合材料具有良好的光催化产氢活性,其产氢... 本文通过简单的一步水热法得到Ni_(2)P-NiS双助催化剂,之后采用溶剂蒸发法将Ni_(2)P-NiS与g-C_(3)N_(4)纳米片结合构建获得无贵金属的Ni_(2)P-NiS/g-C_(3)N_(4)异质结。研究结果表明,优化后的复合材料具有良好的光催化产氢活性,其产氢速率最高可到6892.7μmol·g^(−1)·h^(−1),分别为g-C_(3)N_(4)(150μmol·g^(−1)·h^(−1))、15%NiS/g-C_(3)N_(4)(914.5μmol·g^(−1)·h^(−1))和15%Ni_(2)P/g-C_(3)N_(4)(1565.9μmol·g^(−1)·h^(−1))的46.1、7.5和4.4倍。这主要归因于Ni_(2)P-NiS相比Ni_(2)P和NiS单体具有更好的载流子转移能力,其与g-C_(3)N_(4)形成的肖特基势垒能有效促进光生载流子在二者界面上的分离,同时Ni_(2)P-NiS能进一步降低析氢过电势,进而显著增强了表面析氢反应动力学。本研究为开发稳定、高效的非贵金属产氢助剂提供了实验基础。 展开更多
关键词 Ni_(2)P-NiS g-C_(3)N_(4) 助催化剂 肖特基结 光催化分解水
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Dissolved organic matter removal using magnetic anion exchange resin treatment on biological effluent of textile dyeing wastewater 被引量:14
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作者 jun fan Haibo Li +2 位作者 Chendong Shuang Wentao Li Aimin Li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第8期1567-1574,共8页
This study investigated the removal of dissolved organic matter(DOM) from real dyeing bio-treatment effluents(DBEs) with the use of a novel magnetic anion exchange resin(NDMP).DOMs in two typical DBEs were fract... This study investigated the removal of dissolved organic matter(DOM) from real dyeing bio-treatment effluents(DBEs) with the use of a novel magnetic anion exchange resin(NDMP).DOMs in two typical DBEs were fractionized using DAX-8/XAD-4 resin and ultrafiltration membranes. The hydrophilic fractions and the low molecular weight(MW)(〈3 kDa) DOM fractions constituted a major portion(〉50%) of DOMs for the two effluents. The hydrophilic and low MW fractions of both effluents were the greatest contributors of specific UV254absorbance(SUVA254),and the SUVA254 of DOM fractions decreased with hydrophobicity and MW. Two DBEs exhibited acute and chronic biotoxicities. Both acute and chronic toxicities of DOM fractions increased linearly with the increase of SUVA254 value. Kinetics of dissolved organic carbon(DOC) removal via NDMP treatment was performed by comparing it with that of particle active carbon(PAC). Results indicated that the removal of DOC from DBEs via NDMP was 60%,whereas DOC removals by PAC were lower than 15%. Acidic organics could be significantly removed with the use of NDMP. DOM with large MW in DBE could be removed significantly by using the same means. Removal efficiency of NDMP for DOM decreased with the decrease of MW. Compared with PAC,NDMP could significantly reduce the acute and chronic bio-toxicities of DBEs. NaCl/NaOH mixture regenerants,with selected concentrations of 10% NaCl(m/m)/1%NaOH(m/m),could improve desorption efficiency. 展开更多
关键词 Textile dyeing Secondary/biological effluent Advanced treatment Magnetic resin Anion exchange
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2D mesoporous ultrathin Cd0.5Zn0.5S nanosheet:Fabrication mechanism and application potential for photocatalytic H2 evolution 被引量:10
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作者 Wenhua Xue Wenxi Chang +2 位作者 Xiaoyun Hu jun fan Enzhou Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第1期152-163,共12页
Two-dimensional mesoporous ultrathin Cd0.5Zn0.5S nanosheets with a thickness of~1.5 nm were fabricated using a multistep chemical transformation strategy involving inorganic–organic hybrid ZnS-ethylenediamine(denoted... Two-dimensional mesoporous ultrathin Cd0.5Zn0.5S nanosheets with a thickness of~1.5 nm were fabricated using a multistep chemical transformation strategy involving inorganic–organic hybrid ZnS-ethylenediamine(denoted as ZnS(en)0.5)as a hard template.Inorganic–organic hybrid ZnS(en)0.5,Cd0.5Zn0.5S(en)x,and Cd0.5Zn0.5S nanosheets were sequentially fabricated,and their transformation processes were analyzed in detail.The fabricated Cd0.5Zn0.5S nanosheets exhibited high photocatalytic hydrogen evolution reaction activity in the presence of a sacrificial agent.The Cd0.5Zn0.5S nanosheets exhibited remarkably high H2 production activity of~1395μmol∙h^−1∙g^−1 in pure water with no co-catalyst,which is the highest value reported thus far for bare photocatalysts,to the best of our knowledge.The high activity of these nanosheets is attributed to their distinct nanostructure(e.g.,short transfer distance of photoinduced charge carriers,large number of unsaturated surface atoms,and large surface area).Moreover,ternary NiCo2S4 nanoparticles were employed to facilitate the charge separation and enhance the surface kinetics of H2 evolution.The H2 production rate reached~62.2 and~2436μmol∙h^−1∙g^−1 in triethanolamine and pure water,respectively,over the NiCo2S4/Cd0.5Zn0.5S heterojunctions.The result indicated that the Schottky junction was critical to the enhanced activity.The proposed method can be used for fabricating other highly efficient CdZnS-based photocatalysts for solar-energy conversion or other applications. 展开更多
关键词 MESOPOROUS ULTRATHIN Cd0.5Zn0.5S nanosheets PHOTOCATALYSIS Hydrogen evolution
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UV-VIS-NIR-induced extraordinary H2 evolution over W_(18)O_(49)/Cd_(0.5)Zn_(0.5)S:Surface plasmon effect coupled with S-scheme charge transfer 被引量:9
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作者 Wenhua Xue Hongli Sun +3 位作者 Xiaoyun Hu Xue Bai jun fan Enzhou Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第2期234-245,共12页
In this work,a novel plasmon-assisted UV-vis-NIR-driven W_(18)O_(49)/Cd_(0.5)Zn_(0.5)S heterostructure photocatalyst was obtained by a facile ultrasonic-assisted electrostatic self-assembly strategy.The hybrid exhibit... In this work,a novel plasmon-assisted UV-vis-NIR-driven W_(18)O_(49)/Cd_(0.5)Zn_(0.5)S heterostructure photocatalyst was obtained by a facile ultrasonic-assisted electrostatic self-assembly strategy.The hybrid exhibits extraordinary H2 evolution activity of 147.7 mmol·g^(-1)·h^(-1) at room temperature due to the efficient charge separation and expanded light absorption.Our investigation shows that the unique Step-scheme(S-scheme)charge transfer and the‘hot electron’injection are both responsible for the extraordinary H2 evolution process,depending on the wavelength of the incident light.Moreover,by accelerating the surface reaction kinetics,the activity can be further elevated to 306.1 mmol·g^(-1)·h^(-1),accompanied by a high apparent quantum yield of 45.3% at 365±7.5 nm.This work provides us a potential strategy for the highly efficient conversion of the solar energy by elaborately combining a nonstoichiometric ratio plasmonic material with an appropriate active photocatalyst. 展开更多
关键词 S-scheme Hydrogen Plasmonic material W_(18)O_(49) Cd_(0.5)Zn_(0.5)S
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Optimizing water and nitrogen inputs for winter wheat cropping system on the Loess Plateau,China 被引量:9
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作者 QiuPing FU QuanJiu WANG +1 位作者 XinLei SHEN jun fan 《Journal of Arid Land》 SCIE CSCD 2014年第2期230-242,共13页
Optimal use of water and fertilizers can enhance winter wheat yield and increase the efficiencies of water and fertilizer usage in dryland agricultural systems. In order to optimize water and nitrogen (N) management... Optimal use of water and fertilizers can enhance winter wheat yield and increase the efficiencies of water and fertilizer usage in dryland agricultural systems. In order to optimize water and nitrogen (N) management for winter wheat, we conducted field experiments from 2006 to 2008 at the Changwu Agro-ecological Experimental Station of the Chinese Academy of Sciences on the Loess Plateau, China. Regression models of wheat yield and evapotranspiration (ET) were established in this study to evaluate the water and fertilizer coupling effects and to determine the optimal coupling domain. The results showed that there was a positive effect of water and N fertilizer on crop yield, and optimal irrigation and N inputs can significantly increase the yield of winter wheat. In the drought year (2006-2007), the maximum yield (Yma~) of winter wheat was 9.211 t/hm2 for the treatment with 324 mm irriga- tion and 310 kg/hm2 N input, and the highest water use efficiency (WUE) of 16.335 kg/(hm2.mm) was achieved with 198 mm irrigation and 274 kg/hm2 N input. While in the normal year (2007-2008), the maximum winter wheat yield of 10.715 t/hm2 was achieved by applying 318 mm irrigation and 291 kg/hm2 N, and the highest WUE was 18.69 kg/(hm2.mm) with 107 mm irrigation and 256 kg/hm2 N input. Crop yield and ET response to irrigation and N inputs followed a quadratic and a line function, respectively. The optimal coupling domain was determined using the elas- ticity index (El) and its expression in the water-N dimensions, and was represented by an ellipse, such that the global maximum WUE (WUErnax) and Ymax values corresponded to the left and right end points of the long axis, respectively. Considering the aim to get the greatest profit in practice, the optimal coupling domain was represented by the lower half of the ellipse, with the Yma~ and WUE^ax on the two end points of the long axis. Overall, we found that the total amount of irrigation for winter wheat should not exceed 324 ram. In addition, our optimal coupling domain visually reflects the optimal range of water and N inputs for the maximum winter wheat yield on the Loess Plateau, and it may also provide a useful reference for identifying appropriate water and N inputs in agricultural applications. 展开更多
关键词 water-fertilizer coupling water use efficiency optimal coupling domain yield winter wheat
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热暴露对7A85铝合金微观组织和力学性能的影响
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作者 王浩 赵君文 +3 位作者 范军 张海成 黄兴民 韩靖 《材料工程》 EI CAS CSCD 北大核心 2023年第9期107-116,共10页
选用7A85-T74锻造铝合金为实验材料,研究室温至240℃内热暴露5 h后的合金微观组织、拉伸性能及冲击吸收能量,并结合透射电子显微镜分析微观组织对合金力学性能的影响机理。结果表明:在80~240℃热暴露温度范围内,7A85-T74铝合金晶粒尺寸... 选用7A85-T74锻造铝合金为实验材料,研究室温至240℃内热暴露5 h后的合金微观组织、拉伸性能及冲击吸收能量,并结合透射电子显微镜分析微观组织对合金力学性能的影响机理。结果表明:在80~240℃热暴露温度范围内,7A85-T74铝合金晶粒尺寸变化不大,但沉淀相随温度升高有显著变化;在120℃以内,随热暴露温度的升高,析出物尺寸、拉伸性能和冲击吸收能量整体变化不大,沉淀强化机制为位错切过析出物和位错绕过析出物的混合机制;随着热暴露温度由120℃升高至240℃,析出物的平均半径由室温下的3.8 nm增加至12.3 nm,析出物由η'相向η相转变,合金的屈服强度和抗拉强度显著下降,较室温分别下降45.7%和33.5%,伸长率、断面收缩率和冲击吸收能量显著升高,沉淀强化机制转变为位错绕过析出物,断裂方式由沿晶断裂和韧窝型穿晶断裂组成的混合断裂转变为韧窝型穿晶断裂。基于沉淀强化理论讨论析出物尺寸对合金强度与冲击吸收能量的影响,理论分析结果与实验结果相符。 展开更多
关键词 7A85铝合金 热暴露 微观组织 力学性能
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Crustal flow beneath the eastern margin of the Tibetan plateau 被引量:6
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作者 Jieshou Zhu junmeng Zhao +2 位作者 Xiaotao Jiang jun fan Chuntao Liang 《Earthquake Science》 CSCD 2012年第5期469-483,共15页
In large continental orogens, an important research topic is the behavior of deep crustal and upper mantle deformation, and the flow styles of ductile material. The morphology of the eastern margin of the Tibetan plat... In large continental orogens, an important research topic is the behavior of deep crustal and upper mantle deformation, and the flow styles of ductile material. The morphology of the eastern margin of the Tibetan plateau, adjacent to the Sichuan basin, is characterized by very steep relief with high mountain ranges. The crust beneath this region slows the velocities in the middle and lower crust. We have adopted a relatively dense network to inverse the detailed structure of the crust and upper mantle along the eastern margin of the Tibetan plateau and Sichuan basin, using teleseismic data via receiver function analysis. The results are in-line with the hypothesis that viscous crustal material is flowing beneath the eastern margin of the Tibetan plateau and that this process drives overlying crustal material around the strong and rigid Sichuan basin. When the viscous material hits this obstruction, flows are divided into two or more branches with different directions. The upper part of the upwelling viscous flow produces the pressure to intrude the upper crust, thereby driving uplift of mountain ranges and high peaks. In contrast, the lower part of the downwelling viscous flow produces the pressure to intrude the lower crust and upper mantle to deepen the Moho discontinuity, causing observed crustal thickening. 展开更多
关键词 eastern margin of the Tibetan plateau viscous crustal flow upwelling and downwelling mountain range uplift deepened Moho discontinuity
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Clinicopathological Features and Prognostic Value of KRAS/NRAS/BRAF Mutations in Colorectal Cancer Patients of Central China 被引量:5
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作者 Xiao-na CHANG Fu-mei SHANG +11 位作者 Hong-yu JIANG Chen CHEN Zhe-yan ZHAO Sheng-he DENG jun fan Xiao-chuan DONG Ming YANG Yan LI Kai-lin CAI Li LIU Hong-li LIU Xiu NIE 《Current Medical Science》 SCIE CAS 2021年第1期118-126,共9页
The incidence of colorectal cancer(CRC)is increasing in China,with high mortality.Here,we aimed to evaluate the latest clinicopathological features and prognostic value of the KRAS/NRAS/BRAF mutation status in CRC pat... The incidence of colorectal cancer(CRC)is increasing in China,with high mortality.Here,we aimed to evaluate the latest clinicopathological features and prognostic value of the KRAS/NRAS/BRAF mutation status in CRC patients in Central China.The clinical data of 1549 CRC patients with stage I-IV disease diagnosed at Union Hospital,Tongji Medical College of Huazhong University of Science and Technology from 2015 to 2017 were collected and analyzed retrospectively.KRAS/NRAS/BRAF mutations were detected by real-time quantitative polymerase chain reaction(q-PCR)in 410 CRC patients,with mutation frequencies of KRAS,NRAS and BRAF of 47.56%,2.93%and 4.15%,respectively.The gene mutation status and clinicopathological characteristics of 410 patients with CRC who underwent qPCR were analyzed.The KRAS and BRAF gene mutations were related to the pathological differentiation and number of metastatic lymph nodes.The BRAF gene mutation was also associated with cancer thrombosis in blood vessels.Cox regression analysis showed that there was no statistically significant difference in the overall survival(OS)between patients with KRAS,NRAS mutants and wild-type CRC patients,while the BRAF gene mutation was negatively correlated with the OS rate of CRC patients.It is suggested that the BRAF gene mutation may be an independent risk factor for the prognosis of CRC. 展开更多
关键词 colorectal cancer KRAS mutation NRAS mutation BRAF mutation PROGNOSIS
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基于活性组分微化学状态调控的高性能Rh/CeO_(2)-ZrO_(2)-Al_(2)O_(3)催化剂构筑及三效催化性能
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作者 牟嘉琳 陈柳伶 +5 位作者 范君 曾路 江雪 焦毅 王健礼 陈耀强 《物理化学学报》 SCIE CAS CSCD 北大核心 2023年第12期132-144,共13页
近年来,贵金属Pt、Pd、Rh价格不断攀升,提高贵金属利用效率成为未来汽油车三效催化剂的发展趋势之一。本文协同液相还原和气氛热处理技术精细调控贵金属铑(Rh)的微化学状态,以优化低含量Rh基催化剂的催化性能。同时,采用X射线粉末衍射(X... 近年来,贵金属Pt、Pd、Rh价格不断攀升,提高贵金属利用效率成为未来汽油车三效催化剂的发展趋势之一。本文协同液相还原和气氛热处理技术精细调控贵金属铑(Rh)的微化学状态,以优化低含量Rh基催化剂的催化性能。同时,采用X射线粉末衍射(XRD)、H2-程序升温还原(H2-TPR)、CO化学吸附、X射线光电子能谱(XPS)、CO-漫反射红外(COFTIR)、透射电镜(TEM)和原位漫反射傅里叶变换红外吸收光谱(in situ DRIFTS)等催化剂表征方法,详细研究了Rh微化学状态(价态比例、分散性等)与催化性能之间的关系。活性测试结果表明,通过上述协同方法制备的re-Rh/CeO_(2)-ZrO_(2)-Al_(2)O_(3)-H2(re-Rh/CZA-H2)催化剂表现出最好的催化活性,并且拓宽了空燃比操作窗口,其T90值分别比液相还原法和浸渍法合成的催化剂低30–73℃和51–86℃。此外,通过协同方法制备的催化剂老化后也表现出优异的催化活性和高温热稳定性,其T50和T90值均低于新鲜样品。构效关系结果表明,re-Rh/CZA-H2催化剂优异的催化性能归因于Rh物种具有最佳价态比例和高分散性,从而增加了活性位点的数量。同时,re-Rh/CZA-H2-a催化剂具有相当优异的高温热稳定性,这归因于载体材料的结构稳定性,及活性Rh物种的高含量和高分散,从而暴露出更多的活性位点,促进反应物的吸附和转化。因此,采用本工作提出的协同方法来调整贵金属的微化学状态,可以提高催化剂的催化活性、高温稳定性以及空燃比操作窗口,为设计低负载量Rh基三效催化剂提供一个新思路。 展开更多
关键词 微化学状态 三效催化剂 液相还原 价态比例 气氛热处理技术
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Modeling of bistatic scattering from an underwater non-penetrable target using a Kirchhoff approximation method 被引量:4
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作者 Bin Wang Wen-huan Wang +3 位作者 jun fan Kai-qi Zhao Fu-lin Zhou Li-wen Tan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第7期1097-1106,共10页
A numerical triangulation and transformation into the time domain of a Kirchhoff approximation(KA)method is proposed for the modeling of bistatic scattering from an underwater non-penetrable target.The time domain sol... A numerical triangulation and transformation into the time domain of a Kirchhoff approximation(KA)method is proposed for the modeling of bistatic scattering from an underwater non-penetrable target.The time domain solution in this approximation can be split up into two parts:the solution of reflected field,contributing around the specular direction,and the solution of shadow radiation,contributing around the forward direction.An average solution in the time domain satisfying the reciprocity principle is presented.The solution is expressed in terms of non-singular functions.The proposed method is validated against a normal mode method for bistatic scattering from a rigid sphere.Moreover,the reflected and shadow highlights on the surface of the sphere are shown to verify the integration surface of the reflected field and shadow radiation.It is also tested against a finite element method and an experiment involving a scaled Benchmark Target Strength Simulation Submarine model.The time-angle bistatic spectra for the model are evaluated by the direct and transformed average solutions of KA,and the former accelerates its speed of calculation.The results are good,and show that this method can be used to predict the bistatic scattered field of a non-penetrable target. 展开更多
关键词 Kirchhoff approximation Bistatic scattering Time domain RECIPROCITY EXPERIMENT
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Synthesis of NaYF_(4):Yb,Er upconversion nanoparticle-based optomagnetic multifunctional composite for drug delivery system 被引量:4
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作者 Xuhua Liang jun fan +1 位作者 Yanyan Zhao Ruyi Jin 《Journal of Rare Earths》 SCIE EI CAS CSCD 2021年第5期579-586,共8页
Optomagnetic multifunctional composite has attracted much attention in recent years because of its promising application prospect in bioimaging,analysis,detection,disease diagnosis,and targeted drug delivery.To explor... Optomagnetic multifunctional composite has attracted much attention in recent years because of its promising application prospect in bioimaging,analysis,detection,disease diagnosis,and targeted drug delivery.To explore a dual-targeted therapy for cancer,a novel class of optomagnetic multifunctional composite(UCNP-Fe_(3)O_(4)@MSNs-FA)was successfully synthesized by using upconversion nanoparticles(UCNPs)as nucleus,embedding Fe_(3)O_(4)nanoparticles into the SiO_(2)coating layer,and modifying the surface with folic acid(FA)to strengthen its tumor targeting performance.The properties of the composite were extensively studied.The obtained composite possesses excellent upconversion fluorescence,good dispersion,high specific surface area(229.347 m^(2)/g),and saturation magnetization value(10.9 A m^(2)/g).Its drug loading co ntent and encapsulation efficiency can reach as high as 14.2%and 47.3%,respectively,using doxorubicin hydrochloride(DOX)as model drug.The DOX-UCNP-Fe_(3)O_(4)@MSNs-FA system shows excellent sustained drug release and strong pH-dependent performance,in which the drug release would be accelerated at the slightly acidic microenvironment in the tumor;thus,the system can realize the targeted treatment of cancers.The viability of L929 cells demonstrates the good biocompatibility of the composite.Furthermore,DOX-UCNP-Fe_(3)O_(4)@MSNs-FA exhibits specific cytotoxicity to folate receptor(FR)positive tumor cells,whereas DOX has weak toxicity to FR-negative cells.Therefore,the as-prepared UCNP-Fe_(3)O_(4)@MSNs-FA can potentially be used as an anti-cancer targeted drug delivery system and enhance the therapeutic efficacy against FR-positive tumor cells. 展开更多
关键词 Optomagnetic composite Targeted drug delivery system PH-RESPONSIVE Upconversion luminescence Rare earths
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Nonmuscle myosin IIA promotes the internalization of influenza A virus and regulates viral polymerase activity through interacting with nucleoprotein in human pulmonary cells 被引量:3
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作者 Jian Chen Jian Liu +6 位作者 Zhilu Chen Daobin Feng Cuisong Zhu jun fan Shuye Zhang Xiaoyan Zhang Jianqing Xu 《Virologica Sinica》 SCIE CAS CSCD 2023年第1期128-141,共14页
Influenza A virus(IAV),responsible for seasonal epidemics and recurring pandemics,represents a global threat to public health.Given the risk of a potential IAV pandemic,it is increasingly important to better understan... Influenza A virus(IAV),responsible for seasonal epidemics and recurring pandemics,represents a global threat to public health.Given the risk of a potential IAV pandemic,it is increasingly important to better understand virushost interactions and develop new anti-viral strategies.Here,we reported nonmuscle myosin IIA(MYH9)-mediated regulation of IAV infection.MYH9 depletion caused a profound inhibition of IAV infection by reducing viral attachment and internalization in human lung epithelial cells.Surprisingly,overexpression of MYH9 also led to a significant reduction in viral productive infection.Interestingly,overexpression of MYH9 retained viral attachment,internalization,or uncoating,but suppressed the viral ribonucleoprotein(vRNP)activity in a minigenome system.Further analyses found that excess MYH9 might interrupt the formation of vRNP by interacting with the viral nucleoprotein(NP)and result in the reduction of the completed vRNP in the nucleus,thereby inhibiting subsequent viral RNA transcription and replication.Together,we discovered that MYH9 can interact with IAV NP protein and engage in the regulation of vRNP complexes,thereby involving viral replication.These findings enlighten new mechanistic insights into the complicated interface of host-IAV interactions,ultimately making it an attractive target for the generation of antiviral drugs. 展开更多
关键词 Myosin IIA(MYH9) Influenza A virus(IAV) vRNP activity Virus-host interactions Virus entry
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Heat rate variability and dyssomnia and their correlations to neurological defects in cerebral infarction patients complicated by insomnia A concurrent non-randomized case-control study 被引量:4
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作者 Jianping Chu Xueli Shen +2 位作者 jun fan Changhai Chen Shuyang Lin 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第1期66-70,共5页
BACKGROUND: Heart rate variability refers to the beat-to-beat alteration in heart rate. It is usually a slight periodic variation of R-R intervals. Much information of autonomic nerve system balance can be obtained b... BACKGROUND: Heart rate variability refers to the beat-to-beat alteration in heart rate. It is usually a slight periodic variation of R-R intervals. Much information of autonomic nerve system balance can be obtained by measuring the heart rate variability of patients. It remains to be shown whether heart rate variability can be used as an index for determining the severity of insomnia and cerebral infarction. OBJECTIVE: This study aimed to analyze the correlation for each frequency spectrum parameter of heart rate variability with an insomnia index, as well as the degree of neurological defects in patients with simple cerebral infarction and cerebral infarction complicated by insomnia. The goal was to verify the feasibility of frequency spectrum parameters for heart rate variability as a marker for insomnia and cerebral infarction. DESIGN: A case-control observation. SETTING: Department of Neurology, First Hospital Affiliated to China Medical University. PARTICIPANTS: Sixty inpatients, and/or outpatients, with cerebral infarction were admitted to the 202 Hospital of Chinese PLA between December 2005 and October 2006, confirmed by CT, and recruited to the study. According to the insomnia condition (insomnia is defined by a Pittsburgh Sleep Quality Index score 〉 7), the patients were assigned to a simple cerebral infarction group and a cerebral infarction complicated by insomnia group, with 30 subjects in each group. Thirty additional subjects, who concurrently received examinations and were confirmed to not suffer from cerebral infarction and insomnia, were recruited into the control group. Written informed consent was obtained from each subject for laboratory specimens. The protocol was approved by the Hospital's Ethics Committee. METHODS: Following admission, each subject's neurological impairment was assessed with the National Institutes of Health Stroke Scale and Pittsburgh Sleep Quality Index. Heart rate variability of each subject was measured with an autonomic nerve analyzer (Weijin Science and Technology Co., Ltd., Taiwan). Each frequency spectrum parameter of heart rate variability was obtained, including very low frequency, low frequency, high frequency, total power, R-R interval, and its mean square. In addition, percentage of low frequency, high frequency, and ratio of low frequency to high frequency were calculated. For each heart rate frequency spectrum parameter, the difference between groups was analyzed. Moreover, correlations of each frequency spectrum parameter with insomnia and disease condition were analyzed. Data from each index, which were not normally distributed, were processed by logarithmic transformation. The t-test was used for the comparison of intergroup differences. Single-factor linear regression analysis and t-test were used for the analysis of factor-factor correlation and coefficient of correlation, respectively. MAIN OUTCOME MEASURES: (1) Differences of scores in the National Institutes of Health Stroke Scale and Pittsburgh Sleep Quality Index between the simple cerebral infarction group and the cerebral infarction complicated by insomnia group. (2) Differences of heart rate variability parameters between the simple cerebral infarction group and the control group. (3) Correlation of heart rate variability parameters, the Pittsburgh Sleep Quality Index score, and the neurological impairment score. RESULTS: Sixty patients and thirty healthy controls were included in the final analysis. (1) The scores of the Pittsburgh Sleep Quality Index and the neurological impairment were significantly higher in the cerebral infarction complicated by insomnia group compared to the simple cerebral infarction group (P 〈 0.05-0.01). (2) R-R interval was significantly longer in the simple cerebral infarction group than in the control group, while R-R interval variance and high-frequency band were significantly lower in the simple cerebral infarction group compared to the control group (P 〈 0.05). (3) For cerebral infarction patients with insomnia, the Pittsburgh Sleep Quality Index score was significantly positively correlated with neurological impairment (r = 0.54, P 〈 0.01). The low-frequency band, very low-frequency band, high-frequency band, R-R interval variance, total power, R-R interval, and the percentage of high-frequency were significantly negatively correlated with the National Institutes of Health Stroke Scale score (r =4).45 to 4).90, P 〈 0.054).01) and with the Pittsburgh Sleep Quality Index scores (r = 4).56 to 4).36, P 〈 0.054).01). CONCLUSION: Each heart rate variability parameter can be used as an index for assessing dyssomnia and neurologic impairment (r =4).56 to 4).36, P 〈 0.054).01). 展开更多
关键词 heart rate variability cerebral infarction dyssomnia
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