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61.
62.
Global economic and pollution concerns are having a major impact on how modern engine oils are being formulated. Modern engine oil specifications mandate reduced levels of phosphorus and sulfur to protect the efficacy of pollution control devices. In addition, modern engine oil must also be more fuel efficient than earlier generations to reduce greenhouse gas emissions and the impact of high priced gasoline and diesel fuel to the consumer. At the same time, oxidation, wear, and corrosion performance of the oil must not be compromised. Multifunctional additives are useful formulation tools that help formulators meet these tough new challenges. One such additive is the organo-borate ester/amide. Originally conceived as an organic friction modifier, this patented technology is really a multifunctional additive that addresses the global economic and pollution concerns. With the addition of boron, this unique commercial organic friction modifier also imparts antioxidancy, antiwear and anticorrosion properties to engine oil. In addition, the organo-borate ester/amide is compatible with pollution control devices because it does not contain sulfur or phosphorus. Work is on going to uncover additional beneficial properties of this chemistry. 相似文献
63.
M. Foltyn M. Wasiucionek J.E. Garbarczyk J.L. Nowinski S. Gierlotka B. Palosz 《Journal of power sources》2007
A series of Ag+-ion conducting composites consisting of glasses of the AgI–Ag2O–B2O3 system and hard Al2O3 powder matrix were synthesized by a high-pressure route (pressure 7.7 GPa, temperature 100–200 °C). The composition of the glasses was described by the general formula: xAgI·(100 − x)(0.667Ag2O·0.333B2O3), where x = 40, 50 and 60. Alumina powder (2 μm average grain size) was added to the glass in 50/50 proportions (by volume). 相似文献
64.
无铅低熔玻璃的研究及其进展 总被引:3,自引:0,他引:3
随着欧盟RoHS绿色指令的颁布和人类环保意识的增强,低熔点玻璃无铅化已越来越受到人们的重视。概述了无铅低熔玻璃的国内外研究现状,对无铅硼酸盐、磷酸盐、钒酸盐玻璃等体系的组成以及物化性能进行了较为全面的介绍,并分析了无铅低熔玻璃今后发展的难点和趋势。 相似文献
65.
以壳聚糖-甘油磷酸钠-柠檬酸溶液为液相, 制备了一种新型可注射的硼酸盐玻璃骨水泥, 通过维卡仪、万能试验机、XRD、FTIR、SEM-EDS等探究了液相中柠檬酸浓度(0.1, 0.2和0.4 g/mL)对硼酸盐玻璃骨水泥性能的影响。结果表明: 柠檬酸浓度显著影响骨水泥的凝结时间和可注射性。柠檬酸浓度为0.2 g/mL时获得的骨水泥的凝结时间最短, 为(16±0.5) min; 可注射性最好, 接近100%。骨水泥压缩强度随柠檬酸浓度增大而增强, 最大可达(26.7±1.9) MPa。SEM照片显示骨水泥中生成了许多纳米微粒。XRD、FTIR和EDS等结果证明, 这些纳米微粒主要是硼酸盐、磷酸盐和柠檬酸盐等物质, 而且柠檬酸浓度能够影响骨水泥中硼酸盐晶体的形成。此外, 柠檬酸能够加速玻璃颗粒在磷酸钠盐缓冲液中的降解速率。 相似文献
66.
双草酸硼酸锂制备工艺条件的优化 总被引:1,自引:0,他引:1
宋洋 《材料科学与工程学报》2010,(5)
采用固相法合成了锂离子电池电解质锂盐双草酸硼酸锂(LiBOB)。考察了制备条件对产品纯度和结晶度的影响,由此得出,固相法制备LiBOB的最佳工艺条件为:预保温温度为100℃,预保温时间为6h,加热温度为260℃,加热时间为2h。优化条件下所得产品的纯度高,晶格内粒子的排列紧密,结晶度达到了82.8%。通过对电解质溶液电导率的测定表明,优化条件下所得LiBOB的电解质溶液具有较高的电导率。 相似文献
67.
Ammonia borane NH3BH3 (19.5 wt% H) is able to release hydrogen by hydrolysis in the presence of a catalyst in ambient conditions. This reaction has received considerable attention since 2006, with special focus on the catalytic material. In comparison, important aspects like the nature of the hydrolysis by-product(s) have been much less investigated while a good identification of the borate(s) is required for approaching recyclability. In this context, we present a work based on a systematic approach that aims at characterizing the hydrolysate, its stability in time, and the borate(s) recovered after drying. It is shown that the hydrolysate consists in aqueous B(OH)3 and that the solution (catalyst-free) is stable when stored 6 months under argon atmosphere at 30 °C. The extraction of the water from the hydrolysate was performed at different conditions (vacuum, or air; from −50 to 500 °C). It is observed that the higher the temperature, the lower the hydration degree of the borates. The total dehydration, with the formation of B2O3, can be obtained at heating at 500 °C. The main problem with the hydrolysate is the release of NH3 during the drying stage. A solution is to remove NH3 after hydrolysis and to dry the NH3-free hydrolysate. By this way, H3B3O6 forms. Hence, B2O3 and H3B3O6 could be recovered and recycled into ammonia borane. Besides the identification of the borates, the suitability of ammonia borane for hydrogen production by hydrolysis is discussed, especially in comparison with sodium borohydride NaBH4. 相似文献
68.
Manyboratesareexcellenthostsforrareearthlu minescence ,forexample ,nowbestredphosphorinplasmadisplaypanel (PDP )is (Y1-xGdx)BO3∶Eu[1] .Boratephosphorsdopedwithrareearthionshavebeenrichlystudiedinthepastfewdecades[2 ,3] .RecentlyWuYichengetal .[4 ] synthesizedanewbo rateLa2 CaB10 O19,whichispotentialnonlinearopticalmaterials.InthisworkweselectedLa2 CaB10 O19ashostofluminescencematerialsbecauseitprobablyisabetterhostforrareearthluminescence .Duetotherequirementofplasmadisplaypenal(PDP)… 相似文献
69.
LiBOB电解液在石墨负极上的成膜性能 总被引:1,自引:3,他引:1
利用循环伏安和充放电循环测试,对锂离子电池负极材料[人造石墨E-SLX50和中间相碳微球(MCMB)]与PC作溶剂的LiBOB电解液的相容性进行了研究。石墨表面生成的SEI膜,不仅与电解液的组成和浓度有关,还与石墨的种类及结构有关。在1.0 mol/L LiBOB/PC电解液中,两种材料均能生成稳定的SEI膜;在0.5 mol/L LiBOB/PC电解液中,MCMB可生成稳定的SEI膜,而E-SLX50只有在电解液含EC共溶剂时,通过EC和LiBOB的共同作用,才能生成稳定的SEI膜。 相似文献
70.