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1.
《International Journal of Hydrogen Energy》2022,47(36):16121-16131
Ammonia is considered as a promising hydrogen or energy carrier. Ammonia absorption or adsorption is an important aspect for both ammonia removal, storage and separation applications. To these ends, a wide range of solid and liquid sorbents have been investigated. Among these, the deep eutectic solvent (DES) is emerging as a promising class of ammonia absorbers. Herein, we report a novel type of DES, i.e., metal-containing DESs for ammonia absorption. Specifically, the NH3 absorption capacity is enhanced by ca. 18.1–36.9% when a small amount of metal chlorides, such as MgCl2, MnCl2 etc., are added into a DES composed of resorcinol (Res) and ethylene glycol (EG). To our knowledge, the MgCl2/Res/EG (0.1:1:2) DES outperforms most of the reported DESs. The excellent NH3 absorption performances of metal–containing DESs have been attributed to the synergy of Lewis acid–base and hydrogen bonding interactions. Additionally, good reversibility and high NH3/CO2 selectivity are achieved over the MgCl2/Res/EG (0.1:1:2) DES, which enables it to be a potential NH3 absorber for further investigations. 相似文献
2.
Guoqiang Li He Yang Danying Zuo Jing Xu Hongwei Zhang 《International Journal of Hydrogen Energy》2021,46(24):13044-13049
Gel polymer electrolytes (GPEs) can avoid the electrolyte leakage risk of electrochemical double layer capacitors (EDLCs). But aqueous GPEs often suffer from narrow electrochemical windows. Herein, a series of deep eutectic solvent (DES)-based supramolecular GPEs are firstly developed for carbon-based EDLCs with wide voltage windows. The as-fabricated DES-based GPE shows an ionic conductivity of ~58 mS cm?1, which makes the stable voltage window of a carbon-based EDLC reach 2.4 V. The carbon-based EDLC exhibits a specific capacitance of 32.1 F g?1, an energy density of 24.6 Wh kg?1 and a capacitance retention of ~90% after 15,000 charge-discharge cycles. Moreover, when quinhydrone is added into the DES-based GPE, the specific capacitance and energy density of the corresponding EDLC can be further expanded to 60 F g?1 and 43.6 Wh kg?1, respectively. Therefore, our work may present a universal strategy to prepare novel supramolecular GPEs for high-performance EDLCs with wide voltage windows. 相似文献
3.
Xu Wang Yujie Zhong Qian Sun Dongqing Qi Fuxue Yan Quangang Xian Dong Wang Kui Du Jingyang Wang 《Journal of the American Ceramic Society》2019,102(4):2176-2186
The microstructure evolution and growth behavior of the Al2O3/Y3Al5O12(YAG)/ZrO2 ternary eutectic ceramics during directional solidification were well investigated. During directional solidification of the Al2O3/YAG/ZrO2 ternary eutectic ceramics, {} Al2O3 paralleled with {001}ZrO2 while they did not parallel with {001}YAG at the same time in the competitive growth stage. All of the interfaces parallel to each other finally. The area percentage of the Al2O3/ZrO2 and YAG/ZrO2 interfaces are 40.4 ± 0.2% and 30.8 ± 0.1%, respectively, higher than that of the Al2O3/YAG (28.8 ± 0.2%). The content of Al2O3 and YAG phases are 39.9% and 41.1%, respectively, almost double of that of ZrO2. The interfaces of Al2O3/ZrO2 and YAG/ZrO2 are shorter and more dispersed than that of the Al2O3/YAG. It was found that the interfacial energy of Al2O3/ZrO2 and YAG/ZrO2 interfaces are lower than that of Al2O3/YAG. It can be concluded that interfacial energy plays a decisive role in affecting the crystallographic orientation and interfaces distribution in the Al2O3/YAG/ZrO2 eutectic since the interfaces of Al2O3/ZrO2 and YAG/ZrO2 with lower interfacial energy can be formed more easily during directional solidification. Therefore, the contents of Al2O3/ZrO2 and YAG/ZrO2 interfaces are higher. This study can provide theoretical guidance for interface design of multi-phase materials. 相似文献
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为了实现煤基液体各组分利用价值最大化,本文综述了离子液体和低共熔溶剂对组分组成复杂的煤基液体进行高效萃取分离的研究进展。首先介绍了离子液体和低共熔溶剂的性质及分类;其次根据分离目标的不同,将离子液体和低共熔溶剂对煤基液体典型组分的萃取分离分为四个方面进行阐述:煤基液体提酚、燃料油萃取脱硫、燃料油萃取脱氮、芳烃和脂肪烃的分离。分析表明,离子液体和低共熔溶剂对实际煤基液体的提酚效果较好,能分离出绝大多数的酚类化合物;燃料油萃取脱硫时,离子液体和低共熔溶剂对实际煤基液体的单次脱硫率均不高,需3~5次重复萃取后才能获得理想效果;燃料油中的碱性及非碱性含氮化合物很难被同一种离子液体或低共熔溶剂一次性分离出,导致实际油品的脱氮率较低;大多数离子液体和低共熔溶剂进行芳烃和脂肪烃的分离时不能获得理想的分配系数和选择性,尚无法用于实际芳烃和脂肪烃的分离。氢键、π-π、CH-π、范德华力等分子间相互作用的差异是实现离子液体或低共熔溶剂进行煤基液体典型组分分离的主要原因。依据分离对象,设计合适的离子液体和低共熔溶剂,提高实际煤基液体分离时的萃取率和选择性;分析并解决离子液体和低共熔溶剂用于实际煤基液体各组分分离时可能出现的问题,势必会推进煤基液体高值化分离的工业化进程。 相似文献
7.
Dr. Lei Huang Jan Philipp Bittner Dr. Pablo Domínguez de María Dr. Sven Jakobtorweihen Prof. Dr. Selin Kara 《Chembiochem : a European journal of chemical biology》2020,21(6):811-817
The use of oxidoreductases (EC1) in non-conventional reaction media has been increasingly explored. In particular, deep eutectic solvents (DESs) have emerged as a novel class of solvents. Herein, an in-depth study of bioreduction with an alcohol dehydrogenase (ADH) in the DES glyceline is presented. The activity and stability of ADH in mixtures of glyceline/water with varying water contents were measured. Furthermore, the thermodynamic water activity and viscosity of mixtures of glyceline/water have been determined. For a better understanding of the observations, molecular dynamics simulations were performed to quantify the molecular flexibility, hydration layer, and intraprotein hydrogen bonds of ADH. The behavior of the enzyme in DESs follows the classic dependence of water activity (aW) in non-conventional media. At low aW values (<0.2), ADH does not show any activity; at higher aW values, the activity was still lower than that in pure water due to the high viscosities of the DES. These findings could be further explained by increased enzyme flexibility with increasing water content. 相似文献
8.
对K439B合金进行了1165 ℃/150 MPa,4 h热等静压处理,采用光学显微镜和扫描电镜对比研究了铸态和热等静压态K439B合金的显微组织。结果表明:铸态K439B合金存在0.25%的显微疏松,热等静压后显微疏松基本消除(0.013%)。与铸态相比,经过热等静压处理后合金中的γ/γ′共晶组织体积分数和尺寸减小,各元素分布更加均匀,凝固偏析系数均更接近1。铸态K439B合金枝晶干处γ′相尺寸和体积分数分别是116.9 nm和17.8%,枝晶间部位γ′相尺寸和体积分数分别为244.4 nm和24.9%。热等静压后合金枝晶干部位的γ′相尺寸及体积分数分别为148.0 nm和17.5%,枝晶间部位γ′相尺寸和体积分数分别为159.1 nm和22.8%。热等静压处理使合金枝晶干、枝晶间部位的γ′相尺寸、体积分数和形貌接近,同时γ′相分布变得均匀。 相似文献
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