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排序方式: 共有362条查询结果,搜索用时 31 毫秒
1.
黄力  王德贵 《化学试剂》1996,18(6):366-367
介绍了合成高纯无水的LiBF4和LiAsF6的新方法,并讨论了其合成条件,指出制备多孔状LiF和控制反应温度是合成的关键。  相似文献   
2.
Aqueous rechargeable zinc batteries (ARZBs) are recently prevailing devices that utilize the abundant Zn resources and the merits of aqueous electrolytes to become a competitive alternative for large-scale energy storage. Benefiting from the unique inductive effect and flexible structure, the past five years have experienced a diversiform of phosphate-based polyanion materials that are used as cathodes in ARZBs. In this review, the most recent advances in the Zn2+ storage mechanisms and electrolyte optimization of the phosphate-based cathodes of ARZBs, which mainly focus on vanadium/iron-based phosphates and their derivatives are presented. Furthermore, in addition to significant progress on polyanion phosphate-based cathode materials, the design strategies both for electrode materials and compatible electrolytes are also elaborated to improve the energy density and extend the cycling life of aqueous Zn/polyanion batteries.  相似文献   
3.
Protons in aqueous electrolytes can perform as an additional type of charge carrier for insertion/extraction in addition to the primary carrier cations in aqueous rechargeable batteries. Despite many diverse claims regarding the effect of protons, mutually conflicting experimental results and their interpretations without direct evidence have been reported over the last decade. Systematic examinations and analyses are thus imperative to clarify the conditions of proton insertion in aqueous rechargeable batteries. Utilizing V2O5 as a model cathode and beaker-type cells with a sufficient amount of ZnSO4 aqueous electrolytes in this work, it is demonstrated that protons are inserted into the cathode prior to Zn-ions in low-pH conditions (pH ≤ 3.0). In stark contrast, the influence of protons on the discharge voltage and capacity is insignificant, when either the pH becomes higher (pH ≥ 4.0) or the electrolyte volume is considerably low in coin-type cells. Similar behavior of pH-dependent proton insertion is also verified in Na–, Mg–, and Al-ion electrolytes. Providing a resolution to the controversy regarding proton insertion, the present study emphasizes that the influence of protons substantially varies depending on the pH and relative volume of electrolytes in aqueous batteries.  相似文献   
4.
Membrane decorated with biocides is an effective way to suppress biofilm growth. However, their immediate biocidal effect usually suffers from a significant decline due to the irreversible consumption of the biocides. Here, a smart nanofiltration membrane is reported with rechargeable antibacterial capability that is fabricated by a facile interfacial polymerization via 3-aminophenylboronic acid and trimesoyl chloride on a polysulfone substrate. Biocides bearing diol groups can be grafted onto the membrane surface under neutral/alkaline condition and then released from the surface under acidic environment, due to the pH-responsive feature of boronate ester complexes. The resultant membrane exhibits integrated properties of fast bacterial inactivating efficiency, rechargeable antibacterial capability, and impressive stability. In addition, the achieved membrane shows remarkable separation efficiency to dye/monovalent salt system. The successful fabrication of the membrane with rechargeable anti-bacterial property provides new insights into the development of pH-responsive and sustainable antibacterial membranes.  相似文献   
5.
The use of rechargeable sensors is a promising solution for wireless sensor networks. On this type of network, mobile charging vehicles (MC) are used for charging sensors using wireless energy transfer (WET) technology. In on-demand charging, a sensor transmits a charging request to the service station, and the MC visits the sensor to transfer energy. The key disadvantages of utilizing MC-based WET are its high energy expenditure rate due to mobility, long service time, and slow charging rate. Because of these reasons, sensors deplete their energy and become dead before the MC reaches the requesting nodes to recharge. We have adapted a genetic algorithm-based partial charging scheme to serve the charging requests. Our objective is to improve the survival ratio of the network. Using comprehensive simulations, we analyze the performance of our proposed method and compare it to two other existing approaches. The simulation results demonstrate that our proposed algorithm improves the survival ratio by up to 20 % by developing a dynamic energy threshold function for transmitting charging requests from the sensors and a partial charging schedule using a genetic algorithm.  相似文献   
6.
High‐energy storage devices are in demand for the rapid development of modern society. Until now, many kinds of energy storage devices, such as lithium‐ion batteries (LIBs), sodium‐ion batteries (NIBs), and so on, have been developed in the past 30 years. However, most of the commercially exploited and studied active electrode materials of these energy storage devices possess a single phase with low reversible capacity or unsatisfied cycle stability. Continuous and extensive research efforts are made to develop alternative materials with a higher specific energy density and long cycle life by element doping or surface modification. A novel strategy of forming composite‐structure electrode materials by introducing structure units has attracted great attention in recent years. Herein, based on previous publications on these composite‐structure materials, some important scientific points focusing on the design of composite‐structure materials for better electrochemical performances reveal the distinction of composite structures based on average and local structure analysis methods, and an understanding of the relationship between these interior composite structures and their electrochemical performances is discussed thoroughly. The lithiation/delithiation mechanism and the remaining challenges and perspectives for composite‐structure electrode materials are also elaborated.  相似文献   
7.
结合磁耦合谐振技术,设计了一款基于磁耦合谐振的无线可充电传感器节点.该节点不仅能够实现数据采集和传输,还能通过磁耦合谐振实现能量补充,从而解决WSNs能量受限问题.结合可充电节点的设计要求,基于模块化设计思想,给出其软硬件设计;采用双电源设计架构,以及能量监控和管理,实现节点能量获取与数据传输互不影响.实验结果表明,本文设计的无线可充电传感器节点满足设计要求,使构成无线可充电传感器网络成为可能.  相似文献   
8.
1INTRODUCTION Vanadiumpentoxidexerogel(VXG)filmshavereceivedsignificantattentionduringthelasttwo decadesduetotheirbroadindustrialapplicationsespeciallyinopticalswitchingdevices[1,2],electro chromicdevices[3]andreversiblecathodesforlithi umrechargeablebatteries.ThecommonmethodsofpreparingVXGfilmsareconventionaltech niques,includingpulsedlaserdeposition[4],sput tering[5]andvacuum deposition[6].However,suchmethodsalwaysinvolveconditionsofhightemper atureandvacuum,whichrequirecomplicated…  相似文献   
9.
通过锌膏集气实验、电池放充电实验及电池内阻测试,对无汞可充碱锰电池负极复合添加剂进行了研究.实验表明,含聚氧乙烯基的非离子表面活性剂和氢氧化铟具有缓蚀协同作用,该复合添加剂能够明显减缓电池的自放电,同时改善可充碱锰电池的电化学性能.  相似文献   
10.
可充锂电池复合聚合物电解质研究新进展   总被引:8,自引:0,他引:8  
杜洪彦  程琥  杨勇  林祖赓 《电源技术》2003,27(Z1):250-254
介绍了可充锂电池用聚合物电解质的分类、优越性及其新进展。重点介绍了聚环氧乙烷(PEO)基复合聚合物电解质材料的研究现状,指出近年来纳米复合聚合物电解质的出现为可充锂电池的实用化提供了新的希望。此外,还讨论了纳米无机惰性填料在提高电解质电导率、改善锂/电解质界面稳定性及锂离子迁移数方面的作用机理。  相似文献   
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