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Covalently Bonded Ni Sites in Black Phosphorene with Electron Redistribution for Efficient Metal‑Lightweighted Water Electrolysis
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作者 Wenfang Zhai Ya Chen +5 位作者 Yaoda Liu Yuanyuan Ma Paranthaman Vijayakumar Yuanbin Qin Yongquan Qu Zhengfei Dai 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期233-245,共13页
The metal-lightweighted electrocatalysts for water splitting are highly desired for sustainable and economic hydrogen energy deployments,but challengeable.In this work,a low-content Ni-functionalized approach triggers... The metal-lightweighted electrocatalysts for water splitting are highly desired for sustainable and economic hydrogen energy deployments,but challengeable.In this work,a low-content Ni-functionalized approach triggers the high capability of black phosphorene(BP)with hydrogen and oxygen evolution reaction(HER/OER)bifunctionality.Through a facile in situ electro-exfoliation route,the ionized Ni sites are covalently functionalized in BP nanosheets with electron redistribution and controllable metal contents.It is found that the as-fabricated Ni-BP electrocatalysts can drive the water splitting with much enhanced HER and OER activities.In 1.0 M KOH electrolyte,the optimized 1.5 wt%Nifunctionalized BP nanosheets have readily achieved low overpotentials of 136 mV for HER and 230 mV for OER at 10 mA cm^(−2).Moreover,the covalently bonding between Ni and P has also strengthened the catalytic stability of the Ni-functionalized BP electrocatalyst,stably delivering the overall water splitting for 50 h at 20 mA cm^(−2).Theoretical calculations have revealed that Ni–P covalent binding can regulate the electronic structure and optimize the reaction energy barrier to improve the catalytic activity effectively.This work confirms that Ni-functionalized BP is a suitable candidate for electrocatalytic overall water splitting,and provides effective strategies for constructing metal-lightweighted economic electrocatalysts. 展开更多
关键词 Black phosphorus Water electrolysis ELECTROCATALYST Electron redistribution Covalent functionalization
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Exercise induces tissue hypoxia and HIF-1α redistribution in the small intestine 被引量:2
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作者 Die Wu Wei Cao +3 位作者 Dao Xiang Yi-Ping Hu Beibei Luo Peijie Chen 《Journal of Sport and Health Science》 SCIE 2020年第1期82-89,共8页
Background'. Exercise induces blood flow redistribution among tissues, leading to splanchnic hypoperfusion. Intestinal epithelial cells are positionedbetween the anaerobic lumen and the highly metabolic lamina pro... Background'. Exercise induces blood flow redistribution among tissues, leading to splanchnic hypoperfusion. Intestinal epithelial cells are positionedbetween the anaerobic lumen and the highly metabolic lamina propria with an oxygen gradient. Hypoxia-inducible factor (HIF)-la is piv・otal in the transcriptional response to the oxygen flux.Methods: In this study, the pimonidazole hydrochloride staining was applied to observe the tissue hypoxia in different organs, which might beaffected by the blood flow redistribution. The HIF-la luciferase reporter ROSA26 oxygen-dependent degradation domain (ODD)-Luc/+ mousemodel (ODD domain-Luc;female, n = 3—6/group) was used to detect the HIF-la expression in the intestine. We used 3 swimming models: mod・erate exercise for 30 min, heavy-intensity exercise bearing 5% bodyweight for 1.5 h, and long-time exercise for 3 h.Results'. We found that 1 session of swimming at different intensities could induce tissue hypoxia redistribution in the small intestine, colon, liverand kidney, but not in the spleen, heart, and skeletal muscle. Our data showed that exercise exacerbated the extent of physiological hypoxia in thesmall intestine. Next, using ODD-Luc mice, we found that moderate exercise increased the in vivo HIF-la level in the small intestine. The post・exercise HIF-la level was gradually decreased in a time-dependent manner. Interestingly, the redistribution of tissue hypoxia and the increase ofHIF-la expression were not related to the exercise intensity and duration.Conclusion'. This study provided evidence that the small intestine is the primary target organ for exercise-induced tissue hypoxia and HIF-laredistribution, suggesting that HIF-la may be a potential target for the regulation of gastrointestinal functions after exercise. 展开更多
关键词 Blood flow redistribution Hypoxia-inducible factor-la ODD-Luc Pimonidazole HC1 SWIMMING
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Effects of nitrogen fertilization strategies on nitrogen use efficiency in physiology, recovery, and agronomy and redistribution of dry matter accumulation and nitrogen accumulation in two typical rice cultivars in Zhejiang, China 被引量:2
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作者 XIE Wen-xia, WANG Guang-huo, ZHANG Qi-chun, GUO Hai-chao (Institute for Soil and Water Resources and Environment, Zhejiang University, Hangzhou 310029, China) 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第3期208-216,共9页
Field experiments were conducted in farmers’ rice fields in 2001 and 2002 to study the effects of nitrogen (N) man-agement strategies on N use efficiency in recovery (RE), agronomy (AE) and physiology (PE) and redist... Field experiments were conducted in farmers’ rice fields in 2001 and 2002 to study the effects of nitrogen (N) man-agement strategies on N use efficiency in recovery (RE), agronomy (AE) and physiology (PE) and redistribution of dry matter accumulation (DMA) and nitrogen accumulation (NA) in two typical rice cultivars in Jinhua, Zhejiang Province. This study aimed mainly at identifying the possible causes of poor fertilizer N use efficiency (NUE) of rice in Zhejiang by comparing farmers’ fertilizer practice (FFP) with advanced site-specific nutrient management (SSNM) and real-time N management (RTNM). The results showed that compared to FFP, SSNM and RTNM reduced DMA and NA before panicle initiation and increased DMA and NA at post-flowering. There is no significant difference between SSNM and FFP in post-flowering dry matter redistribution (post-DMR) and post-flowering nitrogen redistribution (post-NR). These results suggest that high input rate of fertilizer N and improper fertilizer N timing are the main factors causing low NUE of irrigated rice in the farmer’s routine practice of Zhejiang. With SSNM, about 15% of the current total N input in direct-seeding early rice and 45% in single rice could be reduced without yield loss in Zhejiang, China. 展开更多
关键词 RECOVERY N USE EFFICIENCY (RE) Agronomic N USE EFFICIENCY (AE) Physiological N USE EFFICIENCY (PE) Nitrogen management Rice Accumulation and redistribution
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POSTMORTEM REDISTRIBUTION KINETICS OF ACONITINE IN RABBITS 被引量:1
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作者 徐威 胡炳蔚 《Journal of Pharmaceutical Analysis》 CAS 1994年第1期41-46,51,共7页
POSTMORTEMREDISTRIBUTIONKINETICSOFACONITINEINRABBITSXuWei;HuBingwei(DepartmentofToxicology,FacultyofForensic... POSTMORTEMREDISTRIBUTIONKINETICSOFACONITINEINRABBITSXuWei;HuBingwei(DepartmentofToxicology,FacultyofForensicMedicine,Xi'anMed... 展开更多
关键词 POSTMORTEM redistribution ACONITINE A-V concentration difference degradation KINETICS
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Redistribution of Pb, Zn and Cu Fractions in Tailing Soils Treated with Different Extractants 被引量:12
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作者 LIU Yun-Guo WANG Xian-Hai +5 位作者 ZENG Guang-Ming LI Xin ZHOU Chun-Hua FAN Ting LI Yong-Li YUAN Xin-Zhong 《Pedosphere》 SCIE CAS CSCD 2006年第3期312-318,共7页
The efficiency of EDTA, HNO3 and CaCl2 as extractants to remove Pb, Zn and Cu from tailing soils without varying soil pH was investigated with distributions of Pb, Zn and Cu being determined before and after extractio... The efficiency of EDTA, HNO3 and CaCl2 as extractants to remove Pb, Zn and Cu from tailing soils without varying soil pH was investigated with distributions of Pb, Zn and Cu being determined before and after extraction using the sequential extraction procedure of the optimized European Community Bureau of Reference (BCR). Results indicated that EDTA and HNO3 were both effective extracting agents.The extractability of extractants for Pb and Zn was in the order EDTA > HNO3 > CaCl2, while for Cu it was HNO3 > EDTA > CaCl2. After EDTA extraction, the proportion of Pb, Zn and Cu in the four fractions varied greatly, which was related to the strong extraction and complexation ability. Before and after extraction with HNO3 and CaCl2, the percentages of Pb, Zn and Cu in the reducible, oxidizable and residual fractions changed little compared to the acid-extractable fraction. The lability of metal in the soil and the kinds of extractants were the factors controlling the effects of metal extraction. 展开更多
关键词 萃取法 重金属 土壤污染 废料
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Variation of nutrient fluxes by rainfall redistribution processes in the forest canopy of an urban larch plantation in northeast China 被引量:2
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作者 Houcai Sheng Na Guo +1 位作者 Cunyong Ju Tijiu Cai 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第4期1259-1269,共11页
Atmospheric deposition(dry and wet deposition)is one of the primary sources of chemical inputs to terrestrial ecosystems and replenishes the nutrient pool in forest ecosystems.Precipitation often acts as a primary tra... Atmospheric deposition(dry and wet deposition)is one of the primary sources of chemical inputs to terrestrial ecosystems and replenishes the nutrient pool in forest ecosystems.Precipitation often acts as a primary transporting agent and solvent;thus,nutrient cycles in forests are closely linked to hydrological processes.We collected precipitation data during a growing season to explore variations in nutrient cycling and nutrient balances in the rainfall redistribution process(wet deposition)in a larch plantation in northeast China.We measured nutrient(NO_(3)^(-),PO_(4)^(3−),Cl^(−),K,Ca,Na,and Mg)inputs via bulk precipitation,throughfall and stemfl ow,and used a canopy budget model to estimate nutrient fl uxes via canopy exchange.Our results suggest that the average concentrations of the base cation(K,Ca,Na,and Mg)showed the following order:stemfl ow>throughfall>bulk precipitation.Throughfall and stemfl ow chemistry dramatically fl uctuated over the growing season when net fl uxes(throughfall+stemfl ow—bulk precipitation)of NO−3,PO3−4,SO2−4,Cl−,K,Ca,Na,and Mg were−6.676 kg·ha^(-1),−1.094 kg·ha^(-1),−2.371 kg·ha^(-1),1.975 kg·ha^(-1),0.470 kg·ha^(-1),−5.202 kg·ha^(-1),−0.336 kg·ha^(-1),and 1.397 kg·ha^(-1),respectively.These results suggest that NO−3,PO3−4,SO2−4,Ca,and Na were retained,while Cl−,K,and Mg were washed off by throughfall and stemfl ow. 展开更多
关键词 Rainfall redistribution Aqueous fluxes Water chemistry Macronutrients input Plantation forest HARBIN
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Leaching and Redistribution of Nutrients in Surface Layer of Red Soils in Southeast China 被引量:14
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作者 SUN BO ZHANG TAOLIN and ZHAO QIGUO(Institute of Soil Science, the Chinese Academy of Sciences, P.O. Box 821, Naniing 210008 China) 《Pedosphere》 SCIE CAS CSCD 2000年第2期135-142,共8页
The leaching and redistribution of nutrients in the surface layer of 4 types of red soils in Southeast China were studied with a lysimeter experiment under filed conditions.Results showed that the leaching concentrate... The leaching and redistribution of nutrients in the surface layer of 4 types of red soils in Southeast China were studied with a lysimeter experiment under filed conditions.Results showed that the leaching concentrated in the rainy season(from April to June).Generally,the leaching of soil nutrients from the surface layer of red soils was in the order of Ca>Mg>K>NO3-N,In fertilization treatment,the total amount of soil nutrients leached out of the surface layer in a red soil derived from granite was the highest in all soils.The uptake by grass decreased the leaching of fertilizer ions in surface layer,particularly for No3-N,Soil total N and exchangeable K,Ca and Mg in the surface layer decreased with leaching and grass uptake during the 2 years without new fertilization of urea,Ca(H2PO4)2,KCl,CaCO3 and MgCO3,Ca moved from the application layer(0-5cm) of fertilizer and accumulated in the 10-30cm depth in the soils studied except that derved from quaternary red clay.The deficiency of soil exchangeable K will become a serious degradation process facing the Southeast China. 展开更多
关键词 红壤 营养成分 淋溶作用 分布规律 中国 云贵高原 长江流域
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Patterns,magnitude,and controlling factors of hydraulic redistribution of soil water by Tamarix ramosissima roots 被引量:12
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作者 TengFei YU Qi FENG +2 位作者 JianHua SI HaiYang XI Wei LI 《Journal of Arid Land》 SCIE CSCD 2013年第3期396-407,共12页
Tamarix spp.(Saltcedar)is a facultative phreatophyte that can tolerate drought when groundwater is not accessed.In addition to deep water uptake,hydraulic redistribution(HR)is another factor contributing to the drough... Tamarix spp.(Saltcedar)is a facultative phreatophyte that can tolerate drought when groundwater is not accessed.In addition to deep water uptake,hydraulic redistribution(HR)is another factor contributing to the drought tolerance of Tamarix spp.In this study,data on soil volumetric moisture content(θ),lateral root sap flow,and relevant climate variables were used to investigate the patterns,magnitude,and controlling factors of HR of soil water by roots of Tamarix ramosissima Ledeb.in an extremely arid land in Northwest China.Results showed evident diurnal fluctuations in θ at the depths of 30 and 50 cm,indicating "hydraulic lift"(HL).θ increased remarkably at 10 and 140 cm but decreased at 30 and 50 cm and slightly changed at 80 cm after rainfall,suggesting a possible "hydraulic descent"(HD).However,no direct evidence was observed in the negative flow of lateral roots,supporting HR(including HL and HD)of T.ramosissima.The HR pathway unlikely occurred via lateral roots;instead,HR possibly occurred through adventitious roots with a diameter of 2-5 mm and a length of 60-100 cm.HR at depths of 20-60 cm ranged from 0.01-1.77 mm/d with an average of 0.43 mm/d,which accounted for an average of 22% of the estimated seasonal total water depletion at 0-160 cm during the growing season.The climate factors,particularly vapor pressure deficit and soil water potential gradient,accounted for at least 33% and 45% of HR variations with depths and years,respectively.In summary,T.ramosissima can be added to the wide list of existing species involved in HR.High levels of HR may represent a considerable fraction of daily soil water depletion and substantially improve plant water status.HR could vary tremendously in terms of years and depths,and this variation could be attributed to climate factors and soil water potential gradient. 展开更多
关键词 液压升降机 土壤水分 水分再分配 控制因素 柽柳 人力资源 气候因素 水势梯度
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Numerical analysis of the effects of rock bolts on stress redistribution around a roadway 被引量:5
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作者 Du Zesheng Qin Botao Tian Fuchao 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第6期975-980,共6页
Besides opening geometry, in situ stress and material properties, opening support also has significant effects on stress redistribution around a roadway. To investigate these effects of rock bolts on the stress redist... Besides opening geometry, in situ stress and material properties, opening support also has significant effects on stress redistribution around a roadway. To investigate these effects of rock bolts on the stress redistribution around a roadway, a series of numerical studies were carried out using the finite difference method. Since the stress changes around a roadway caused by rock bolting is small relative to the in situ stress, they cannot obviously be observed in stress contour plots. To overcome this difficulty, a new result processing methodology was developed using the contouring program Surfer. With this methodology, the effects of rock bolts on stress redistribution can obviously be analyzed. Numerical results show that in the three patterns of rock bolts installed in the roof, in the roof and the two lateral sides, and in all the four sides of the rectangular roadway, the maximum stress magnitude of the increase is 0.931 MPa, 2.46 MPa,and 6.5 MPa, respectively; the bolt number of 5 can form an integrated ground arch; the appropriate length and pre-tensioned force of the rock bolt is 2.0 m and 60 k N, respectively. What is more, the ground arch action under the function of rock bolting is able to be effectively examined. The rock bolts dramatically increase the minor principal stress around a roadway which results in significant increase in material strength. Consequently, the major principal stress that the material can carry will greatly increase.With adequate supports, an integrated ground arch which is critical for the stability of roadway will be formed around the roadway. 展开更多
关键词 巷道应力 锚杆支护 数值分析 分布影响 SURFER软件 应力重分布 材料特性 有限差分法
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Effect of pre-tensioned rock bolts on stress redistribution around a roadway—insight from numerical modeling 被引量:12
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作者 GAO Fu-qiang KANG Hong-pu 《Journal of China University of Mining and Technology》 EI 2008年第4期509-515,共7页
The importance of the pre-tensioned force of rock bolts has been recognized by more and more researchers. To investi- gate the effect of pre-tensioned rock bolts on stress redistribution around roadways, a numerical a... The importance of the pre-tensioned force of rock bolts has been recognized by more and more researchers. To investi- gate the effect of pre-tensioned rock bolts on stress redistribution around roadways, a numerical analysis was carried out using FLAC3D and a special post-process methodology, using surfer, is proposed to process the numerical simulation results. The results indicate that pre-tensioned rock bolts have a significant effect on stress redistribution around a roadway. In the roof, pre-tensioned rock bolts greatly increase vertical stress; as a result, the strength of the rock mass increased significantly which results in a greater capacity of bearing a large horizontal stress. The horizontal stress decreases in the upper section of the roof, indicating that pre-tensioned rock bolts significantly reduce the coefficient and the size of the region concentration of horizontal stress. At the lat- eral side, pre-tensioned rock bolts greatly increase the horizontal stress; therefore, the rock mass strength significantly increases which results also in a greater capacity of bearing a large vertical stress. The greater the size of pre-tensioned force, the larger the region of stress redistribution around a roadway is affected and the higher the size of the stress on the roadway surface the more the rock mass strength increases. 展开更多
关键词 岩石牢固性 压力分布 数字模拟 采矿工程
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Load-redistribution strategy based on time-varying load against cascading failure of complex network 被引量:4
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作者 刘军 熊庆宇 +2 位作者 石欣 王楷 石为人 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期371-377,共7页
Cascading failure can cause great damage to complex networks, so it is of great significance to improve the network robustness against cascading failure. Many previous existing works on load-redistribution strategies ... Cascading failure can cause great damage to complex networks, so it is of great significance to improve the network robustness against cascading failure. Many previous existing works on load-redistribution strategies require global information, which is not suitable for large scale networks, and some strategies based on local information assume that the load of a node is always its initial load before the network is attacked, and the load of the failure node is redistributed to its neighbors according to their initial load or initial residual capacity. This paper proposes a new load-redistribution strategy based on local information considering an ever-changing load. It redistributes the loads of the failure node to its nearest neighbors according to their current residual capacity, which makes full use of the residual capacity of the network. Experiments are conducted on two typical networks and two real networks, and the experimental results show that the new load-redistribution strategy can reduce the size of cascading failure efficiently. 展开更多
关键词 复杂网络 分配策略 连锁故障 变负载 局部信息 剩余容量 工作负载 级联故障
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An Analytical Solution for One-Dimensional Water Infiltration and Redistribution in Unsaturated Soil 被引量:7
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作者 WANG Quan-Jiu R. HORTON FAN Jun 《Pedosphere》 SCIE CAS CSCD 2009年第1期104-110,共7页
Soil infiltration and redistribution are important processes in field water cycle, and it is necessary to develop a simple model to describe the processes. In this study, an algebraic solution for one-dimensional wate... Soil infiltration and redistribution are important processes in field water cycle, and it is necessary to develop a simple model to describe the processes. In this study, an algebraic solution for one-dimensional water infiltration and redistribution without evaporation in unsaturated soil was developed based on Richards equation. The algebraic solution had three parameters, namely, the saturated water conductivity, the comprehensive shape coefflcient of the soil water content distribution, and the soil suction allocation coefficient. To analyze the physical features of these parameters, a relationship between the Green-Ampt model and the algebraic solution was established. The three parameters were estimated based on experimental observations, whereas the soil water content and the water infiltration duration were calculated using the algebraic solution. The calculated soil water content and infiltration duration were compared with the experimental observations, and the results indicated that the algebraic solution accurately described the unsaturated soil water flow processes. 展开更多
关键词 代数解 GREEN-AMPT模型 土壤水分渗透 不饱和土壤
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Verifiable Secret Redistribution for Proactive Secret Sharing Schemes 被引量:4
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作者 于佳 孔凡玉 李大兴 《Journal of Shanghai Jiaotong university(Science)》 EI 2006年第2期236-241,共6页
A new scheme to verifiably redistribute a secret from the old to new shareholders without reconstruction of the secret is presented in this paper. The scheme allows redistribution between different access structures a... A new scheme to verifiably redistribute a secret from the old to new shareholders without reconstruction of the secret is presented in this paper. The scheme allows redistribution between different access structures and between different threshold schemes. A point worth mentioning is that this verifiable secret redistribution (VSR) scheme can identify dishonest old shareholders during redistribution without any assumption. A certain technique is adopted to verify the correctness of the old shares of the secret. As a result, the scheme is very efficient. It can be applied to proactive secret sharing (PSS) schemes to construct more flexible and practical proactive secret sharing schemes. 展开更多
关键词 分配方法 共享技术 网络安全 技术性能
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Membrane redistributions through multi-intercellular exchanges and serial trogocytosis 被引量:2
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作者 Estlbahz Alegre Klave-Yune HoWangYin +6 位作者 Benolt Favier Jeremy Baudhuin Emilie Lesport Marina Daouya Alvaro Gonzalez Edgardo D Carosella Joel LeMaoult 《Cell Research》 SCIE CAS CSCD 2010年第11期1239-1251,共13页
Trogocytosis 是在膜的房间之间的快速的转移并且联系蛋白质。Trogocytic 交换在不同房间类型之间被调查了,主要在二房间的系统,包含一个施主和一种领受人房间类型。这里,我们在一个更复杂的系统学习了 trogocytosis,包含不仅几个... Trogocytosis 是在膜的房间之间的快速的转移并且联系蛋白质。Trogocytic 交换在不同房间类型之间被调查了,主要在二房间的系统,包含一个施主和一种领受人房间类型。这里,我们在一个更复杂的系统学习了 trogocytosis,包含不仅几个有免疫力的房间子集而且多重肿瘤房间。我们证明 CD4+ T 房间, CD8+ T 房间和单核白血球能获得膜补丁和他们由多重同时的 trogocytoses 从不同肿瘤房间包含的未经触动的蛋白质。CD4+ 和 CD8+ T 房间的 trogocytic 能力被发现类似于自体同源的单核白血球的,却劣等。激活的外部血的 mononuclear 房间(PBMC ) 可以也在一个所有自体同源的系统交换在自己之间的膜。为这个原因,单核白血球能够从多重肿瘤房间来源获得膜,并且再把他们转移到自体同源的 T 房间,与一些他们的自己的膜(连续 trogocytosis ) 一起。我们的数据说明在自体同源的激活的有免疫力的受动器房间和他们的环境之间的膜交换的程度,并且包括鈥渂y stander 鈥 ? 房间,本地环境的细胞的内容怎么可以影响有免疫力的受动器房间的功能。 展开更多
关键词 细胞膜 交流 串行 体细胞类型 分发 电池系统 肿瘤细胞 单核细胞
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Solute Redistribution Model for Multicomponent AHoys during Rapid Solidification
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作者 陈魁英 李庆春 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1992年第4期305-306,共2页
1.IntroductionThe solute redistribution models for binary alloys during the rapid solidification havebeen extensively studied in recent years[1-10],but up to now the solute redistribution modelfor multicomponent alloy... 1.IntroductionThe solute redistribution models for binary alloys during the rapid solidification havebeen extensively studied in recent years[1-10],but up to now the solute redistribution modelfor multicomponent alloys has not been reported.In this paper the solute redistribution mod-el for the multicomponent alloys based on the Aziz model is established theoretically. 展开更多
关键词 rapid SOLIDIFICATION SOLUTE redistribution MULTICOMPONENT ALLOYS
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REDISTRIBUTION OF IMPURITY ATOMS AI, Si, Mn AND Cu IN Ni DURING LASER MELTING
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作者 ZHENG Ling, Chongqing Institute of Communications, Chongqing, ChinaZOU Zhirong, LIU Jianglong, Chongqing University, Chongqing, China ZHENG Ling, Lecturer, Department of Mechanical Engineering, Chongqing Institute of Communications, Chongqing 630074, China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1992年第7期77-81,共5页
An explanation of the redistribution of impurity atoms such as Al, Si, Mn and Cu in purenickel during low speed laser melting is made by one-dimensional analysis model for heattransfer. The solid-liquid interface solu... An explanation of the redistribution of impurity atoms such as Al, Si, Mn and Cu in purenickel during low speed laser melting is made by one-dimensional analysis model for heattransfer. The solid-liquid interface solute redistribution seems to be the principal cause thatmakes the impurity atoms redistribute in the depth direction. The diffusion of impurity atomsfrom low to high temperature zones and their surface selective evaporation are believed to benoticeably contributed to the redistribution. 展开更多
关键词 NI laser MELTING IMPURITY ATOM redistribution
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Experimental Observation of Electrie Field Induced C_(60) Redistribution in Benzene Solution
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作者 HAN Yanong GAO Xiaoming +7 位作者 ZHANG Weijun DING Hongyu XIA Yuxing ZANG Wencheng GU Gang YANG Ping DU Youwei FENG Duan 《Chinese Physics Letters》 SCIE CAS CSCD 1993年第11期664-666,共3页
We report the experimental observation of electric field induced Gso redistribution,in benzene solution by thermal blooming change of transmitted light.The pol&riz&tion of C_(60) molecules in external field is... We report the experimental observation of electric field induced Gso redistribution,in benzene solution by thermal blooming change of transmitted light.The pol&riz&tion of C_(60) molecules in external field is analyzed. 展开更多
关键词 BENZENE distribution redistribution
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Impacts of oak deforestation and rainfed cultivation on soil redistribution processes across hillslopes using ^(137)Cs techniques
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作者 Shamsollah Ayoubi Nafiseh Sadeghi +3 位作者 Farideh Abbaszadeh Afshar Mohammad Reza Abdi Mojtaba Zeraatpisheh Jesus Rodrigo-Comino 《Forest Ecosystems》 SCIE CSCD 2021年第3期425-438,共14页
Background:As one of the main components of land-use change,deforestation is considered the greatest threat to global environmental diversity with possible irreversible environmental consequences.Specifically,one exam... Background:As one of the main components of land-use change,deforestation is considered the greatest threat to global environmental diversity with possible irreversible environmental consequences.Specifically,one example could be the impacts of land-use changes from oak forests into agricultural ecosystems,which may have detrimental impacts on soil mobilization across hillslopes.However,to date,scarce studies are assessing these impacts at different slope positions and soil depths,shedding light on key geomorphological processes.Methods:In this research,the Caesium-137(^(137)Cs)technique was applied to evaluate soil redistribution and soil erosion rates due to the effects of these above-mentioned land-use changes.To achieve this goal,we select a representative area in the Lordegan district,central Iran.^(137)Cs depth distribution profiles were established in four different hillslope positions after converting natural oak forests to rainfed farming.In each hillslope,soil samples from three depths(0–10,10–20,and 20–50 cm)and in four different slope positions(summit,shoulder,backslope,and footslope)were taken in three transects of about 20m away from each other.The activity of ^(137)Cs was determined in all the soil samples(72 soil samples)by a gamma spectrometer.In addition,some physicochemical properties and the magnetic susceptibility(MS)of soil samples were measured.Results:Erosion rates reached 51.1 t·ha^(−1)·yr^(−1) in rainfed farming,whereas in the natural forest,the erosion rate was 9.3 t·ha^(−1)·yr^(−1).Magnetic susceptibility was considerably lower in the cultivated land(χhf=43.5×10^(−8)m^(3)·kg^(−1))than in the natural forest(χhf=55.1×10^(−8)m^(3)·kg^(−1)).The lower soil erosion rate in the natural forest land indicated significantly higher MS in all landform positions except at the summit one,compared to that in the rainfed farming land.The shoulder and summit positions were the most erodible hillslope positions in the natural forest and rainfed farming,respectively.Conclusions:We concluded that land-use change and hillslope positions played a key role in eroding the surface soils in this area.Moreover,land management can influence soil erosion intensity and may both mitigate and amplify soil loss. 展开更多
关键词 Land-use change Soil redistribution Topographical changes RADIONUCLIDE Rainfed farming DEFORESTATION
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Charge redistribution caused by sulfur doping of bimetal FeCo phosphides supported on heteroatoms-doped graphene for Zn-air batteries with stable cycling
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作者 Jin-Tao Ren Yi-Dai Ying +2 位作者 Yu-Ping Liu Wei Li Zhong-Yong Yuan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第8期619-630,I0017,共13页
Exploring feasible synthesis approaches to highly efficient and robust bifunctional electrocatalysts toward both oxygen evolution reaction(OER)and oxygen reduction reaction(ORR)is triggering researcher’s even-increas... Exploring feasible synthesis approaches to highly efficient and robust bifunctional electrocatalysts toward both oxygen evolution reaction(OER)and oxygen reduction reaction(ORR)is triggering researcher’s even-increasing interest in rechargeable Zn-air batteries.Herein,sulfur-doped bimetal FeCo phosphide nanoparticles dispersed on N,P,S-tri-doped graphene(donated as S-FeCo3P/NPSG)are rationally prepared through a controllable one-step carbothermal-phosphorization strategy.The modified charge distribution and electron-donor properties of S-FeCo3P/NPSG caused by S decoration render a significantly beneficial effect on the electrocatalytic activities.Consequently,the S-FeCo3P/NPSG electrode exhibits extraordinary bifunctional activities toward oxygen electrochemistry of the OER overpotential of 290 m V at 10 m A cm^(-2) and the ORR half-wave potential of 0.83 V,approaching to that of noblemetal IrO_(2)(289 m V)and Pt/C(0.84 V),respectively,but with more stronger operation stability in alkaline media.When S-FeCo3P/NPSG serves as the air cathode for liquid-state Zn-air battery,the large peak power density and energy density,as well as superb discharge-charge durability(cycling life>600 h)of this device are obtained.Furthermore,all-solid-state Zn-air battery with S-FeCo3P/NPSG as air electrode also displays excellent mechanical flexibility,high power density and stable cycling stability.The self-reconstruction behavior of the S-FeCo3P/NPSG cathode catalysts is also investigated during the electrocatalytic Zn-air battery operation.This work would provide some novel inspiration from aspects of bonding and charge distribution for the rational construction of active and cost-efficient bifucntional oxygen electrocatalysts for energy storage and conversion devices. 展开更多
关键词 Charge redistribution Metal phosphides Bifunctional electrocatalyst Oxygen electrocatalysis Zinc-air batteries
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Change and Redistribution of Immature Fiber Number during Cotton Carding Based on Different Taker-in Speeds
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作者 于学智 郭昕 曹继鹏 《Journal of Donghua University(English Edition)》 EI CAS 2016年第4期625-628,共4页
The change and redistribution of immature fiber number after cotton carding were investigated under different taker-in speeds.The immature fiber contents (IFCs) of card sliver,flat strips,takerin droppings and cylinde... The change and redistribution of immature fiber number after cotton carding were investigated under different taker-in speeds.The immature fiber contents (IFCs) of card sliver,flat strips,takerin droppings and cylinder screen droppings (including droppings under cylinder screen and cylinder-doffer triangle section) produced under different taker-in speeds were tested by using USTER advanced fiber information system (AFIS). Based on these results and relevant data,immature fiber number was calculated. Results show that the carding process makes the immature fiber number increase. After carding, immature fibers are distributed mainly in card sliver,accounting for approximately 90% in their total number. All of the cylinder screen,taker-in and flat have the functions of excluding immature fibers; furthermore,IFC in cylinder screen droppings is the highest,followed successively by those in taker-in droppings,flat strips and card sliver. The IFC of card sliver is the lowest when the taker-in speeds are 1000 and 1400 r/min. 展开更多
关键词 taker-in speed immature fiber content(IFC) FINENESS CARDING redistribution
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