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81.
根据智能云测试系统的特点,并结合实际中通用测试平台的通信机制。为实现快速有效的驱动执行机,在selenium框架基础上,引入了智能云测试系统通信模块的设计与实现。该智能云测试系统的通信机制,采用Carbon-Server作为框架,进行了智能云测试服务提供方、服务调用方通信细节的研究,采用其通信机制对大量单机版测试工具进行整合,形成了一个比较便捷的分布式开发架构,可以较好的模拟大规模组网。结果表明,与通用测试平台的通信机制相比,智能云测试通信系统在实际工程中能够更有效的提高通信效率。  相似文献   
82.
Selenium (Se)‐based rechargeable aluminum batteries (RABs), known as aluminum–selenium (Al–Se) batteries, are an appealing new battery design that holds great promise for addressing the low‐capacity problem of current RAB technology. However, their applications are hindered by mediocre high‐rate capacity (≈100 mAh g?1 at 0.5 A g?1) and insufficient cycling life (50 cycles). Herein, the synthesis of mesoporous carbon fibers (MCFs) by coating mesoporous carbon with short‐length mesopores and tunable mesopore sizes (2.7 to 8.9 nm) coaxially on carbon nanotubes (CNT) is reported. When compositing MCFs with Se for Al–Se batteries, a positive correlation between mesopore size and electrolyte ion diffusivity is observed, however when pore size is increased to 8.9 nm, large voids are created at the interface of CNT core and mesoporous carbon shell, leading to decreased electrode conductivity. The trade‐off between ion diffusivity and interfacial connectivity/conductivity determines MCF with pore size of 7.1 nm as the best host material for Al–Se batteries. The composite cathode delivers high specific capacities (366 and 230 mAh g?1 at 0.5 and 1 A g?1), good rate performance, and excellent cycling stability (152 mAh g?1 after 500 cycles at 2 A g?1), superior over previously reported Se cathodes and other cathodes for RABs.  相似文献   
83.
The potassium–selenium (K–Se) battery is considered as an alternative solution for stationary energy storage because of abundant resource of K. However, the detailed mechanism of the energy storage process is yet to be unraveled. Herein, the findings in probing the working mechanism of the K-ion storage in Se cathode are reported using both experimental and computational approaches. A flexible K–Se battery is prepared by employing the small-molecule Se embedded in freestanding N -doped porous carbon nanofibers thin film (Se@NPCFs) as cathode. The reaction mechanisms are elucidated by identifying the existence of short-chain molecular Se encapsulated inside the microporous host, which transforms to K2Se by a two-step conversion reaction via an “all-solid-state” electrochemical process in the carbonate electrolyte system. Through the whole reaction, the generation of polyselenides (K2Sen, 3 ≤ n ≤ 8) is effectively suppressed by electrochemical reaction dominated by Se2 molecules, thus significantly enhancing the utilization of Se and effecting the voltage platform of the K–Se battery. This work offers a practical pathway to optimize the K–Se battery performance through structure engineering and manipulation of selenium chemistry for the formation of selective species and reveal its internal reaction mechanism in the carbonate electrolyte.  相似文献   
84.
All‐solid‐state Li–S batteries are promising candidates for next‐generation energy‐storage systems considering their high energy density and high safety. However, their development is hindered by the sluggish electrochemical kinetics and low S utilization due to high interfacial resistance and the electronic insulating nature of S. Herein, Se is introduced into S cathodes by forming SeSx solid solutions to modify the electronic and ionic conductivities and ultimately enhance cathode utilization in all‐solid‐state lithium batteries (ASSLBs). Theoretical calculations confirm the redistribution of electron densities after introducing Se. The interfacial ionic conductivities of all achieved SeSx–Li3PS4 (x = 3, 2, 1, and 0.33) composites are 10?6 S cm?1. Stable and highly reversible SeSx cathodes for sulfide‐based ASSLBs can be developed. Surprisingly, the SeS2/Li10GeP2S12–Li3PS4/Li solid‐state cells exhibit excellent performance and deliver a high capacity over 1100 mAh g?1 (98.5% of its theoretical capacity) at 50 mA g?1 and remained highly stable for 100 cycles. Moreover, high loading cells can achieve high areal capacities up to 12.6 mAh cm?2. This research deepens the understanding of Se–S solid solution chemistry in ASSLB systems and offers a new strategy to achieve high‐performance S‐based cathodes for application in ASSLBs.  相似文献   
85.
氢化物-原子荧光法测定水中痕量砷、硒、汞   总被引:2,自引:0,他引:2  
张文芸 《山西化工》2002,22(1):39-41
采用氢化物-原子荧光法测定水中痕量的砷、硒、汞,该法大大提高了灵敏度,砷,硒,汞的检出限分别为0.40μg/L,0.50μg/L,水样的回标回收率在95%-105%之间,其相对标准偏差小于5.0%。该方法已成功地用于大批量水样中砷、硒、汞的测定。  相似文献   
86.
以安琪活性干酵母为出发菌种,分析了培养基初始硒浓度、接种量、装液量、温度、初始pH以及转速等发酵条件对酵母生物量及富硒量的影响,并通过正交试验设计初步确定了培养的最优方案。在最佳的摇瓶培养条件下(初始硒浓度25μg/mL,接种量10%,装液量60/250 mL,温度30℃,初始pH 5.0,摇床转速160 r/min,培养40 h后),该活性干酵母的生物量及富硒量分别达到9.89 g/L、954μg/g.  相似文献   
87.
The objective of this study was to evaluate the presence of heavy metals in the hepatocytes of the animals fed a cadmium-supplemented diet and also receiving zinc and/or selenium in the injection form. The experiment involved four groups of calves (6-8, both sexes) receiving the heavy metals in various combinations for 95 days. Electron micrographs of liver cells were prepared and statistically evaluated using Student's t-test. A modified morphometric apparatus was used for morphometric examination. Exogenous cadmium showed marked accumulation in the hepatocytes. If, however, the cadmium diet was combined with zinc or selenium administration the amount of the reduction product was much lower.  相似文献   
88.
《云南化工》2018,(12):34-35
CIGS薄膜太阳能电池为黄铜矿结构,其光学带隙随Ga含量增多而增加,双带隙梯度结构是高效CIGS电池的基础。  相似文献   
89.
Unipolar n‐type semiconducting polymers based on the benzobisthiadiazole (BBT) unit and its heteroatom‐substituted derivatives are for the first time synthesized by the D‐A1‐D‐A2 polymer‐backbone design strategy. Selenium (Se) substitution is a very effective molecular design, but it has been seldom studied in n‐type polymers. In this study, within the similar conjugated framework, the Se substitution effects on the optical, electrochemical, solid‐state polymer packing, electron mobility, and air‐stability of the target unipolar n‐type polymers are unraveled. Replacing the sulfur (S) atom in the thiadiazole heterocycles with the Se atom leads to narrower bandgaps and deeper lowest unoccupied molecular orbital (LUMO) levels of the n‐type polymers. Furthermore, the Se‐substituted polymer (pSeN‐NDI) shows shorter lamellar packing distances and stronger edge‐on π–π stacking interactions than its S‐counterpart (pSN‐NDI), as observed by the two‐dimensional grazing‐incidence wide‐angle X‐ray scattering (GIWAXS) patterns. With the deeper LUMO level and thin‐film microstructures suitable for transistors, pSeN‐NDI exhibits four‐fold higher electron mobilities (μe) than pSN‐NDI. However, the other Se‐containing polymer, pSeS‐NDI, forms rather amorphous film structures, which is caused by its limited thermal stability and decomposition during the thermal annealing processes, thus giving rise to a lower μe than its S‐counterpart (pBBT‐NDI). Most importantly, pBBT‐NDI demonstrates an electron mobility of 0.039 cm2 V?1 s?1, which is noticeable among the unipolar n‐type polymers based on the BBT and its analogs.  相似文献   
90.
在硝酸、高氯酸、硫酸溶矿方法的基础上,作者用硝酸、氢氟酸溶矿,高氯酸冒烟,趁热加入浓盐酸将硒、碲还原成低价;用三价铁盐消除铜等元素的干扰,以氢化物双道原子荧光法同时测定化探样品中的硒和碲。经国家一级标样验证,这种方法简便可靠,具有较高的灵敏度。硒、碲的检出限分别为:w(Se)/10(-6)=0.01,w(Te)/10(-6)=0.008。  相似文献   
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