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Interface and energy band manipulation of Bi2O3-Bi2S3 electrode enabling advanced magnesium-ion storage
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作者 Qiang Tang Yingze Song +4 位作者 Xuan Cao Cheng Yang Dong Wang Tingting Qin Wei Zhang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第9期3543-3552,共10页
Rechargeable magnesium-ion(Mg-ion)batteries have attracted wide attention for energy storage.However,magnesium anode is still limited by the irreversible Mg plating/stripping procedure.Herein,a well-designed binary Bi... Rechargeable magnesium-ion(Mg-ion)batteries have attracted wide attention for energy storage.However,magnesium anode is still limited by the irreversible Mg plating/stripping procedure.Herein,a well-designed binary Bi_(2)O_(3)-Bi_(2)S_(3)(BO-BS)heterostructure is fulfilled by virtue of the cooperative interface and energy band engineering targeted fast Mg-ion storage.The built-in electronic field resulting from the asymmetrical electron distribution at the interface of electron-rich S center at Bi_(2)S_(3) side and electron-poor O center at Bi_(2)O_(3) side effectively accelerates the electrochemical reaction kinetics in the Mg-ion battery system.Moreover,the as-designed heterogenous interface also benefits to maintaining the electrode integrity.With these advantages,the BO-BS electrode displays a remarkable capacity of 150.36 mAh g^(−1) at 0.67 A g^(-1) and a superior cycling stability.This investigation would offer novel insights into the rational design of functional heterogenous electrode materials targeted the fast reaction kinetics for energy storage systems. 展开更多
关键词 Magnesium-ion battery Bi2O3-Bi2s3 heterostructure interface and energy band engineering Electrochemical reaction kinetics Electrode integrity
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In-doping collaboratively controlling back interface and bulk defects to achieve efficient flexible CZTSSe solar cells
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作者 Quanzhen Sun Yifan Li +6 位作者 Caixia Zhang Shunli Du Weihao Xie Jionghua Wu Qiao Zheng Hui Deng Shuying Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期10-17,I0002,共9页
Focusing on the low open circuit voltage(V_(OC))and fill factor(FF)in flexible Cu_(2)ZnSn(S,Se)_(4)(CZTSSe)solar cells,indium(In)ions are introduced into the CZTSSe absorbers near Mo foils to modify the back interface... Focusing on the low open circuit voltage(V_(OC))and fill factor(FF)in flexible Cu_(2)ZnSn(S,Se)_(4)(CZTSSe)solar cells,indium(In)ions are introduced into the CZTSSe absorbers near Mo foils to modify the back interface and passivate deep level defects in CZTSSe bulk concurrently for improving the performance of flexible device.The results show that In doping effectively inhibits the formation of secondary phase(Cu(S,Se)_(2))and VSndefects.Further studies demonstrate that the barrier height at the back interface is decreased and the deep level defects(Cu_(Sn)defects)in CZTSSe bulk are passivated.Moreover,the carrier concentration is increased and the V_(OC) deficit(V_(OC,def))is decreased significantly due to In doping.Finally,the flexible CZTSSe solar cell with 10.01%power conversion efficiency(PCE)has been obtained.The synergistic strategy of interface modification and bulk defects passivation through In incorporation provides a new thought for the fabrication of efficient flexible kesterite-based solar cells. 展开更多
关键词 Flexible solar cells Cu_(2)Znsn(s se)_(4) Back interface Deep level defects Barrier height
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Boosting redox activity on MXene-induced multifunctional collaborative interface in high Li2S loading cathode for high-energy Li-S and metallic Li-free rechargeable batteries 被引量:8
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作者 Zhiyu Wang Nan Zhang +3 位作者 Mingliang Yu Junshan Liu Song Wang Jieshan Qiu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第10期183-191,共9页
Use of metallic Li anode raises serious concerns on the safety and operational performance of Li-S batteries due to uncontrolled hazard of Li dendrite formation, which is difficultly eliminated as long as the metallic... Use of metallic Li anode raises serious concerns on the safety and operational performance of Li-S batteries due to uncontrolled hazard of Li dendrite formation, which is difficultly eliminated as long as the metallic Li exists in the cells. Pairing lithium sulfide (Li2S) cathode with currently available metallic Lifree high-capacity anodes offers an alternative solution to this challenge. However, the performance of Li2S cathode is primarily restricted by high activation barrier upon initial charge, low active mass utilization and sluggish redox kinetics. Herein, a MXene-induced multifunctional collaborative interface is proposed to afford superb activity towards redox solid-liquid/liquid-liquid phase transformation, strong chemisorption, high conductivity and fast ionic/charge transport in high Li2S loading cathode. Applying collaborative interface effectively reduces initial voltage barrier of Li2S activation and regulates the kinetic behavior of redox polysulfide conversion. Therefore, stable operation of additive-free Li2S cathode with high areal capacities at high Li2S loading up to 9 mg cm^-2 can be achieved with less sacrifice of high capacity and rate capability in Li-S batteries. Rechargeable metallic Li-free batteries are successfully constructed by pairing this high-performance Li2S cathode with high-capacity metal oxide anodes, which delivers superior energy density to current Li-ion batteries. 展开更多
关键词 Lithium sULFIDE HIGH-CAPACITY CATHODE interface MXene Li-s batteries
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Effects of Coverage,Water,and Defects on Catechol/TiO2 Interface 被引量:1
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作者 Min Wei Fan Jin +3 位作者 Chenggong Liang Lijuan Zhang Shizhu Qiao Yuchen Ma 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第6期935-944,I0060-I0063,I0073,共15页
Catechol adsorbed on TiO_(2)is one of the simplest models to explore the relevant properties of dye-sensitized solar cells.However,the effects of water and defects on the electronic levels and the excitonic properties... Catechol adsorbed on TiO_(2)is one of the simplest models to explore the relevant properties of dye-sensitized solar cells.However,the effects of water and defects on the electronic levels and the excitonic properties of the catechol/TiO_(2)interface have been rarely explored.Here,we investigate four catechol/TiO_(2)interfaces aiming to study the influence of coverage,water,and defects on the electronic levels and the excitonic properties of the catechol/TiO_(2)interface through the first-principles many-body Green’s function theory.We find that the adsorption of catechol on the rutile(110)surface increases the energies of both the TiO_(2)valence band maximum and conduction band minimum by approximately 0.7 eV.The increasing coverage and the presence of water can reduce the optical absorption of charge-transfer excitons with maximum oscillator strength.Regarding the reduced hydroxylated TiO_(2)substrate,the conduction band minimum decreases greatly,resulting in a sub-bandgap of 2.51 eV.The exciton distributions in the four investigated interfaces can spread across several unit cells,especially for the hydroxylated TiO2substrate.Although the hydroxylated TiO_(2)substrate leads to a lower open-circuit voltage,it may increase the separation between photogenerated electrons and holes and may therefore be beneficial for improving the photovoltaic efficiency by controlling its concentration.Our results may provide guidance for the design of highly efficient solar cells in future. 展开更多
关键词 Catechol/TiO2 interface EXCITON CHARGE-TRANsFER Many-body Green’s function theory
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Over 12%efficient kesterite solar cell via back interface engineering 被引量:2
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作者 Yunhai Zhao Zixuan Yu +8 位作者 Juguang Hu Zhuanghao Zheng Hongli Ma Kaiwen Sun Xiaojing Hao Guangxing Liang Ping Fan Xianghua Zhang Zhenghua Su 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第12期321-329,I0008,共10页
Kesterite Cu_(2)ZnSn(S,Se)_(4)(CZTSSe)has attracted considerable attention as a non-toxic and earthabundant solar cell material.During selenization of CZTSSe film at high temperature,the reaction between CZTSSe and Mo... Kesterite Cu_(2)ZnSn(S,Se)_(4)(CZTSSe)has attracted considerable attention as a non-toxic and earthabundant solar cell material.During selenization of CZTSSe film at high temperature,the reaction between CZTSSe and Mo is one of the main reasons that result in unfavorable absorber and interface quality,which leads to large open circuit voltage deficit(VOC-def)and low fill factor(FF).Herein,a WO_(3)intermediate layer introduced at the back interface can effectually inhibit the unfavorable interface reaction between absorber and back electrode in the preliminary selenization progress;thus high-quality crystals are obtained.Through this back interface engineering,the traditional problems of phase segregation,voids in the absorber and over thick Mo(S,Se)_(2)at the back interface can be well solved,which greatly lessens the recombination in the bulk and at the interface.The increased minority carrier diffusion length,decreased barrier height at back interface contact and reduced deep acceptor defects give rise to systematic improvement in VOCand FF,finally a 12.66%conversion efficiency for CZTSSe solar cell has been achieved.This work provides a simple way to fabricate highly efficient solar cells and promotes a deeper understanding of the function of intermediate layer at back interface in kesterite-based solar cells. 展开更多
关键词 Cu_(2)Znsn(s se)_(4) WO_(3)intermediate layer Crystal growth Minority carrier diffusion length interface contact quality
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Effects of thermodynamics parameters on mass transfer of volatile pollutants at air-water interface
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作者 Li-ping Chen Kai-yun Xuan +1 位作者 Bin Zhou Guang-fa Deng 《Water Science and Engineering》 EI CAS CSCD 2015年第3期211-216,共6页
A transient three-dimensional coupling model based on the compressible volume of fluid (VOF) method was developed to simulate the transport of volatile pollutants at the air-water interface. VOF is a numerical techn... A transient three-dimensional coupling model based on the compressible volume of fluid (VOF) method was developed to simulate the transport of volatile pollutants at the air-water interface. VOF is a numerical technique for locating and tracking the free surface of water flow. The relationships between Henry's constant, thermodynamics parameters, and the enlarged topological index were proposed for nonstandard conditions. A series of experiments and numerical simulations were performed to study the transport of benzene and carbinol. The simulation results agreed with the experimental results. Temperature had no effect on mass transfer of pollutants with low transfer free energy and high Henry's constant. The temporal and spatial distribution of pollutants with high transfer free energy and low Henry's constant was affected by temperature. The total enthalpy and total transfer free energy increased significantly with temperature, with significant fluctuations at low temperatures. The total enthalpy and total transfer free energy increased steadily without fluctuation at high temperatures. 展开更多
关键词 Henry's constant Mass transfer at interface Thermodynamics parameters Topological index Volatile pollutants
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Exploring how hydrogen at gold-sulfur interface affects spin transport in single-molecule junction
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作者 Jing Zeng Ke-Qiu Chen Yanhong Zhou 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第8期525-530,共6页
Very recently,experimental evidence showed that the hydrogen is retained in dithiol-terminated single-molecule junction under the widely adopted preparation conditions,which is in contrast to the accepted view[Nat.Che... Very recently,experimental evidence showed that the hydrogen is retained in dithiol-terminated single-molecule junction under the widely adopted preparation conditions,which is in contrast to the accepted view[Nat.Chem.11351(2019)].However,the hydrogen is generally assumed to be lost in the previous physical models of single-molecule junctions.Whether the retention of the hydrogen at the gold-sulfur interface exerts a significant effect on the theoretical prediction of spin transport properties is an open question.Therefore,here in this paper we carry out a comparative study of spin transport in M-tetraphenylporphyrin-based(M=V,Cr,Mn,Fe,and Co;M-TPP)single-molecule junction through Au-SR and Au-S(H)R bondings.The results show that the hydrogen at the gold-sulfur interface may dramatically affect the spin-filtering efficiency of M-TPP-based single-molecule junction,depending on the type of transition metal ions embedded into porphyrin ring.Moreover,we find that for the Co-TPP-based molecular junction,the hydrogen at the gold-sulfur interface has no obvious effect on transmission at the Fermi level,but it has a significant effect on the spin-dependent transmission dip induced by the quantum interference on the occupied side.Thus the fate of hydrogen should be concerned in the physical model according to the actual preparation condition,which is important for our fundamental understanding of spin transport in the single-molecule junctions.Our work also provides guidance in how to experimentally identify the nature of gold-sulfur interface in the single-molecule junction with spin-polarized transport. 展开更多
关键词 transport properties molecular electronic devices gold-sulfur interface density-functional theory nonequilibrium Green’s functions
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Synthesis of Silver Sulf ide Quantum Dots Via the Liquid–Liquid Interface Reaction in a Rotating Packed Bed Reactor
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作者 Qing Liu Yuan Pu +2 位作者 Zhijian Zhao Jiexin Wang Dan Wang 《Transactions of Tianjin University》 EI CAS 2020年第4期273-282,共10页
We developed the high-gravity coupled liquid-liquid interface reaction technique on the basis of the rotating packed bed(RPB)reactor for the continuous and ultrafast synthesis of silver sulfide(Ag2S)quantum dots(QDs)w... We developed the high-gravity coupled liquid-liquid interface reaction technique on the basis of the rotating packed bed(RPB)reactor for the continuous and ultrafast synthesis of silver sulfide(Ag2S)quantum dots(QDs)with near-infrared(NIR)luminescence.The formation of Ag2S QDs occurs at the interface of microdroplets,and the average size of Ag2S QDs was 4.5 nm with a narrow size distribution.Ag2S QDs can disperse well in various organic solvents and exhibit NIR luminescence with a peak wavelength at 1270 nm under 980-nm laser excitation.The mechanism of the process intensification was revealed by both the computational fluid dynamics simulation and fluorescence imaging,and the mechanism is attributed to the small and uniform droplet formation in the RPB reactor.This study provides a novel approach for the continuous and ultrafast synthesis of NIR Ag2S QDs for potential scale-up. 展开更多
关键词 Ag2s quantum dots Near-infrared luminescence Rotating packed bed Liquid-liquid interface reaction Process intensification
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Solution of Singular Integrals in Mathematical Model of Mode I Crack near Strength Mismatched Interface
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作者 Sunil Bhat Vijay G. Ukadgaonker 《American Journal of Computational Mathematics》 2012年第2期156-162,共7页
Characteristics of Mode I crack near the interface of elasticity matched but plasticity and strength mismatched materials differ from those of the crack in a homogenous body. Interface body of different strength influ... Characteristics of Mode I crack near the interface of elasticity matched but plasticity and strength mismatched materials differ from those of the crack in a homogenous body. Interface body of different strength influences the plastic or cohesive zone at the crack tip in parent body. The mathematical model for load line opening of the crack near the interface in linear elastic regime involves singular integrals. The paper presents explicit solution of these integrals with the help of Cauchy’s principal value theorem. Cases of thin and thick welds between the materials are investigated. Solutions of the integrals are well substantiated. Final results are provided in a consolidated form. 展开更多
关键词 Crack OPENING Displacement sINGULAR INTEGRALs strength MIsMATCH WELD interface Cauchy’s Principal Value Theorem
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Effects of Ca(Y)-Si modifier on interface morphology and solute segregation during directional solidification of an austenite medium Mn steel
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作者 Gaofei Liang Zhenming Xu Jianguo Li 《Journal of University of Science and Technology Beijing》 CSCD 2005年第4期335-339,共5页
The austenite medium Mn steel modified with controlled additions of Ca, Y, Si were directionally solidified using the vertical Bridgman method to study the effects of Ca(Y)-Si modifier on the solid-liquid (S-L) in... The austenite medium Mn steel modified with controlled additions of Ca, Y, Si were directionally solidified using the vertical Bridgman method to study the effects of Ca(Y)-Si modifier on the solid-liquid (S-L) interface morphology and solute segregation. The interface morphology and the C and Mn segregation of the steel directionally solidified at 6.9 μtrn/s were investigated with an image analysis and a scanning electron microscope equipped with energy dispersive X-ray analysis. The 0.5wt% Ca-Si modified steel is solidified with a planar S-L interface. The interface of the 1.0wt% Ca-Si modified steel is similar to that of the 0.5wt% Ca-Si modified steel, but with larger nodes. The 1.5wt% Ca-Si modified steel displays a cellular growth parttern. The S-L interface morphology of the 0.5wt% Ca-Si+1.0wt% Y-Si modified Mn steel appears as dendritic interface, and primary austenite dendrites reveal developed lateral branching at the quenched liquid. In the meantime, the independent austenite colonies are formed ahead of the S-L interface. A mechanism involving constitutional supercooling explains the S-L interface evolution. It depends mainly on the difference in the contents of Ca, Y, and Si ahead of the S-L interface. The segregation of C and Mn ahead of the S-L interface enhanced by the modifiers is observed. 展开更多
关键词 austenite Mn steel modification solid-liquid s-L) interface morphology solute segregation directional solidification
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50 Gbit/s前传光模块关键技术研究与应用展望
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作者 盛夏 马涛 +1 位作者 刘昊 冯佳 《电信科学》 北大核心 2024年第5期23-37,共15页
随着全球5G网络的规模化商用及移动互联网流量的迅猛增长,更为丰富的无线频谱资源得以释放,高速率光模块在无线前传网络中的需求日益凸显。聚焦于50 Gbit/s前传光模块的关键技术,深入剖析了前传网络的两种主要组网方式,分析了前传链路... 随着全球5G网络的规模化商用及移动互联网流量的迅猛增长,更为丰富的无线频谱资源得以释放,高速率光模块在无线前传网络中的需求日益凸显。聚焦于50 Gbit/s前传光模块的关键技术,深入剖析了前传网络的两种主要组网方式,分析了前传链路的典型传输距离及链路损耗情况,探讨了10 km场景下粗波分复用(coarse wavelength division multiplex,CWDM)中各波长的最大色散值和最小色散值,并研究了相应的色散补偿策略,通过实验验证了不同多径干扰(multi-path interference,MPI)强度下系统光功率代价的变化,详细分析了多径干扰噪声对系统误码性能的潜在影响,为前传光模块参数的优化提供了重要的理论依据。此外,深入研究了50 Gbit/s前传光模块的光电芯片技术方案,对多种不同类型光模块的参数性能进行了严格的测试,提出了针对50 Gbit/s前传光模块光电接口参数的标准化建议,详细介绍了当前50 Gbit/s前传光模块在国内外的标准现状,并展望了未来应用的发展趋势。 展开更多
关键词 5G网络 50 Gbit/s前传光模块 色散 多径干扰 光电接口参数
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Cu-石墨炔/双金属钨酸盐S型异质结协同增强光催化析氢
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作者 周正宇 姚惠琴 +3 位作者 吴有林 李腾 椿范立 靳治良 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第10期52-54,共3页
采用有机法和水热法合成了Cu-石墨炔和CoNiWO_(4)并构建Cu-石墨炔/CoNiWO_(4)S型异质结。在保留催化剂强氧化还原能力的同时,通过内建电场和能带弯曲的协同作用促进了光生载流子的高效分离和转移。Cu-石墨炔的引入有效提高了复合催化剂... 采用有机法和水热法合成了Cu-石墨炔和CoNiWO_(4)并构建Cu-石墨炔/CoNiWO_(4)S型异质结。在保留催化剂强氧化还原能力的同时,通过内建电场和能带弯曲的协同作用促进了光生载流子的高效分离和转移。Cu-石墨炔的引入有效提高了复合催化剂的光吸收能力和导电性,抑制了光生载流子的复合。同时,Cu-石墨炔独特的二维平面网络结构提供了丰富的活性位点,从而促进了光催化反应的进行。密度泛函理论(DFT)计算表明,Cu的表面等离子体共振效应产生的热电子转移到石墨炔上,促进氢气的析出。本研究为Cu-石墨炔和镍钴基催化剂在光催化制氢领域提供了新的参考。 展开更多
关键词 Cu-石墨炔 s-型异质结 界面工程设计 析氢反应 DFT
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Interconnected microstructure and flexural behavior of Ti_(2)C-Ti composites with superior Young’s modulus
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作者 Fengbo Sun Rui Zhang +3 位作者 Fanchao Meng Shuai Wang Lujun Huang Lin Geng 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第9期2088-2101,共14页
To enhance the Young’s modulus(E)and strength of titanium alloys,we designed titanium matrix composites with intercon-nected microstructure based on the Hashin-Shtrikman theory.According to the results,the in-situ re... To enhance the Young’s modulus(E)and strength of titanium alloys,we designed titanium matrix composites with intercon-nected microstructure based on the Hashin-Shtrikman theory.According to the results,the in-situ reaction yielded an interconnected microstructure composed of Ti_(2)C particles when the Ti_(2)C content reached 50vol%.With widths of 10 and 230 nm,the intraparticle Ti lamellae in the prepared composite exhibited a bimodal size distribution due to precipitation and the unreacted Ti phase within the grown Ti_(2)C particles.The composites with interconnected microstructure attained superior properties,including E of 174.3 GPa and ultimate flexural strength of 1014 GPa.Compared with that of pure Ti,the E of the composite was increased by 55% due to the high Ti_(2)C content and interconnected microstructure.The outstanding strength resulted from the strong interfacial bonding,load-bearing capacity of interconnected Ti_(2)C particles,and bimodal intraparticle Ti lamellae,which minimized the average crack driving force.Interrupted flexural tests revealed preferential crack initiation along the{001}cleavage plane and grain boundary of Ti_(2)C in the region with the highest tensile stress.In addition,the propagation can be efficiently inhibited by interparticle Ti grains,which prevented the brittle fracture of the composites. 展开更多
关键词 titanium matrix composites titanium carbide interface Young’s modulus flexural behavior
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Feasibility Study of Neurofeedback Therapy for Alzheimer’s Disease
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作者 Ruyu Li Min Yang 《Advances in Alzheimer's Disease》 CAS 2024年第3期49-64,共16页
Objective: This study aims to evaluate the feasibility and effectiveness of neurofeedback therapy based on brain-computer interface (BCI) games in enhancing cognitive functions and reducing disruptive behaviors in pat... Objective: This study aims to evaluate the feasibility and effectiveness of neurofeedback therapy based on brain-computer interface (BCI) games in enhancing cognitive functions and reducing disruptive behaviors in patients with Alzheimer’s disease (AD). Methods: Forty-six AD patients aged 49 - 76 years were recruited for the study. Neurofeedback regulation was conducted using a BCI game designed to modulate EEG rhythms. Cognitive function was assessed using MMSE, MoCA, and ADAS-cog scales before and after a 10-day training period. EEG measurements were taken to evaluate changes in brain activity complexity. Statistical analyses were performed using SPSS25.0 software to compare pre- and post-training scores. Results: Post-intervention results showed significant improvement in the cognitive function of AD patients. The total scores of MMSE, MoCA, and ADAS-cog scales increased significantly (P < 0.01). Notable improvements were observed in memory, language, and attention domains. EEG complexity in the left frontal area also showed a significant increase (P < 0.05). Additionally, the disruptive behaviors of patients were significantly reduced, improving their overall quality of life. Conclusions: Neurofeedback therapy based on BCI games is a promising intervention for enhancing cognitive functions and reducing disruptive behaviors in AD patients. This innovative approach demonstrates significant potential for clinical application, providing a non-invasive method to improve patient outcomes. Further studies with larger sample sizes and long-term follow-ups are recommended to validate these findings and explore the specific effects of NFB training on different cognitive impairment levels. 展开更多
关键词 Alzheimer’s Disease Brain-Computer interface NEUROFEEDBACK Cognitive Function Disruptive Behaviors
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藻源性黑水团环境效应Ⅲ:对水-沉积物界面处Fe-S-P循环的影响 被引量:19
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作者 刘国锋 范成新 +3 位作者 张雷 申秋实 王兆德 韩士群 《中国环境科学》 EI CAS CSCD 北大核心 2014年第12期3199-3206,共8页
利用静态模拟实验装置研究了藻源性黑水团发生过程中沉积物表层上覆水和沉积物间隙水中Fe-S-P的变化过程.结果表明:加入藻细胞后很快形成厌氧、还原环境,使得沉积物中Fe-S-P发生强烈的生物地球化学变化;实验第1d,表层上覆水中的Fe2+、SO... 利用静态模拟实验装置研究了藻源性黑水团发生过程中沉积物表层上覆水和沉积物间隙水中Fe-S-P的变化过程.结果表明:加入藻细胞后很快形成厌氧、还原环境,使得沉积物中Fe-S-P发生强烈的生物地球化学变化;实验第1d,表层上覆水中的Fe2+、SO42-、S2-含量高达4.993,242.0,387.57mg/L,为对照样柱中的1.8倍、2.2倍和18.8倍;在沉积物4cm处其浓度分别为8.5,40.0,65.3mg/L.随后,沉积物表层上覆水中Fe2+、S2-含量表现出一个先快速增加、随后降低的趋势,其浓度分别在实验的第3,2d达到最大值为11.1,634.6mg/L.沉积物中PO43--P浓度受Fe-P解析等具有滞后性,从实验的第2d后开始直至实验结束时表现为其含量持续增加,到实验结束时其浓度为39.450mg/L,为对照样柱中的242倍.上覆水和间隙水中Fe-S-P含量的变化,反映了藻华聚集形成的厌氧环境中发生了剧烈的生物地球化学反应,从而使得沉积物中形成的Fe2+、S2-和PO43--P不断向上覆水体中扩散,对形成黑水团的水体生态系统的恢复造成阻碍和不良影响. 展开更多
关键词 黑水团 水-沉积物界面 铁硫磷循环 环境效应
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继电保护装置与通信设备2 Mbit/s光接口互联技术 被引量:12
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作者 杨俊权 王勇 +1 位作者 利韶聪 李舒涛 《南方电网技术》 2011年第4期65-67,共3页
目前在电网运行中复用继电保护装置与通信光传输设备间以2 Mbit/s电口互连,存在着连接复杂、光电转换设备缺少统一的接口标准、光电转换设备不能网管监控等问题。因此,提出了适用于保护装置和通信设备的2 Mbit/s光接口方式及其技术标准... 目前在电网运行中复用继电保护装置与通信光传输设备间以2 Mbit/s电口互连,存在着连接复杂、光电转换设备缺少统一的接口标准、光电转换设备不能网管监控等问题。因此,提出了适用于保护装置和通信设备的2 Mbit/s光接口方式及其技术标准,并完成了相关测试工作。结果显示,复用继电保护装置与通信光传输设备之间采用统一标准的2 Mbit/s光接口直连通信是可行的,但其可靠性和稳定性尚待进一步验证。 展开更多
关键词 继电保护 2Mbit/s速率光接口 继电保护 通信传输设备 光接口标准
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表面态密度分布和源漏电阻对6H-SiC PMOS器件特性的影响 被引量:7
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作者 郜锦侠 张义门 +1 位作者 张玉明 汤晓燕 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第4期408-413,共6页
建立了一个价带附近的界面态密度分布模型 ,并用该模型较好地模拟了 6 H- Si C PMOS器件的阈值电压随温度变化的趋势、C- V特性以及转移特性 .理论 C- V特性曲线是用数值解泊松方程的方法得到的 ,在解泊松方程的过程中考虑了场致离化效... 建立了一个价带附近的界面态密度分布模型 ,并用该模型较好地模拟了 6 H- Si C PMOS器件的阈值电压随温度变化的趋势、C- V特性以及转移特性 .理论 C- V特性曲线是用数值解泊松方程的方法得到的 ,在解泊松方程的过程中考虑了场致离化效应 .由于 Si C PMOS器件的源漏电阻比较大 ,因此 ,在计算强反型情况下的漏电流时 ,同时考虑了源漏电阻的影响 .结果表明 。 展开更多
关键词 表面态密度分布 源漏电阻 6H-siCPMOs 器件特性
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基于神经网络和Dempster-Shafter信息融合的煤岩界面预测 被引量:17
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作者 梁义维 熊诗波 《煤炭学报》 EI CAS CSCD 北大核心 2003年第1期86-90,共5页
针对煤岩界面识别精度无法满足采煤机自动调高的情况 ,提出采用神经网络融合工作面的三边信息 ,使用D -S证据理论再将此信息和不断获得的煤岩界面识别信息进行二次融合 ,从而实现在线融合和在线预测 ,不断提高预测精度 .仿真结果显示 :... 针对煤岩界面识别精度无法满足采煤机自动调高的情况 ,提出采用神经网络融合工作面的三边信息 ,使用D -S证据理论再将此信息和不断获得的煤岩界面识别信息进行二次融合 ,从而实现在线融合和在线预测 ,不断提高预测精度 .仿真结果显示 :该方法不仅对地质条件好的工作面有效 ,而且对断层也有一定的适应性 ;同时 ,具有优良的容错性 . 展开更多
关键词 煤岩界面 神经网络 D-s理论 长壁开采 采煤机 滚筒 地质条件
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S基因在甘蓝EDFs上的高分辨率荧光原位杂交定位(英文) 被引量:5
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作者 杨昆 漆红艳 +1 位作者 朱利泉 王小佳 《Acta Genetica Sinica》 SCIE CAS CSCD 北大核心 2006年第3期277-284,共8页
植物细胞壁及细胞质的存在和植物染色体所具有的高浓缩特性,限制高效率原位杂交定位在植物细胞内的进行。针对小型染色体芸薹属植物采用常规方法DNA制备纤维的效果不佳的特点,新建制备方法:利用减数分裂前期的染色体为材料, 在硅化的玻... 植物细胞壁及细胞质的存在和植物染色体所具有的高浓缩特性,限制高效率原位杂交定位在植物细胞内的进行。针对小型染色体芸薹属植物采用常规方法DNA制备纤维的效果不佳的特点,新建制备方法:利用减数分裂前期的染色体为材料, 在硅化的玻片上先后通过蛋白酶解和乙醇:乙酸(3:1)的适当处理,采用移动界面法制备EDFs。制备的EDFs比未经伸长处理的染色体在经向和横向方面分别取得较高程度的伸长与膨胀,长度可达到89-257 gm,比相应地中期染色体增长30-107倍, 分辨率可达42.8-53.0 kb。利用SRK和SCR两种探针同时在甘蓝粗线期染色体和EDFs上进行了原位杂交,首次鉴定了S基因座在其单倍体基因组中单拷贝性。在杂交信号检测中尽管未经过信号放大,但仍然可以观察到清晰的绿色信号;经荧光显微镜观察,在单一的EDF上发现两个相距1 μm的SCR和SRK的信号点,由此得出局部分辨率为4 kb的最高伸长度。 展开更多
关键词 空间分辨率 EDFs制备 s基因库 移动界面 EDF-荧光原位杂交 s基因定位 杂交图谱数量分析
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PZT/SiO_2/Si界面的XPS分析 被引量:3
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作者 于军 周文利 +1 位作者 曹广军 谢基凡 《华中理工大学学报》 CSCD 北大核心 1996年第1期82-84,共3页
采用SOL-GEL工艺在SiO2/Si衬底上制备了铁电薄膜,对PZT/SiO2/Si结构进行了XPS分析,结果表明,在PZT铁电薄膜和硅衬底之间加SiO2使F/S界面得到了改善.
关键词 PZT 二氧化硅 铁电薄膜 界面 XPs
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