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81.
文章计算了废清液蒸发过程中液相组成及密度,在证实计算方法可靠的情况下,对青岛碱厂废清液蒸发过程进行了预测,给出了预测结果,同时计算补充了20℃Na+,Ca∥Cl--H2O体系的相图数据及等密度线,举例说明了等密度线的应用。 相似文献
82.
金属盐沉淀法提取茶多酚影响因素的研究 总被引:8,自引:0,他引:8
对金属盐沉淀法提取茶多酚进行了研究 探讨了茶叶量、浸提水量、浸提时间、浸提次数、浸提水温度、金属盐及其加入量、酸溶时酸的用量、萃取时间、萃取次数等各因素对茶多酚提取率的影响 研究表明 ,AlCl3 和ZnSO4 对茶多酚的沉淀具有协同作用 确定了最佳提取工艺条件 :10 g茶末 ,14 0mL水 ,10 0℃水中浸提 10min ,加入AlCl3 ·6H2 O 0 .60 g ,ZnSO4 ·7H2 O 1.0 7g ,用乙酸乙脂萃取 4次 ,其茶多酚的提取率可达 18%~ 2 0 % 相似文献
83.
84.
Extraction experiments were carried out to determine the suitable solvent and carrier type. Five different solvents and carriers were used and verified. Trichloromethane and tetraoctyl ammonium chlorides were found to be the most appropriate solvent and carrier type for this study. The coupled transport of cyanide ions in aqueous solutions through bulk liquid membrane (BLM) was investigated using various stirring speeds and temperatures. Cyanide ion transport through BLM technique was analyzed according to coupled non-steady state kinetics of two consecutive irreversible first order reactions. The influences of the kinetic parameters (k1d, k2m, k2a, Rmmax, tmax, Jdmax, Jamax) for the various stirring speeds in the system were established. The removal and recovery efficiencies of the cyanide ions transported from aqueous solutions in 360 min were 99.4 and 82%, respectively. As the stirring speed was increased, both the efficiency of transport and recovery of cyanide ions from aqueous solutions were increased. On the other hand, for maximum membrane entrance (Jdmax) and exit (Jamax) fluxes the activation energies were calculated as 21.6 kcal/mol and 10.5 kcal/mol, respectively. 相似文献
85.
Myofibrillar Protein Solubility of Model Beef Batters as Affected by Low Levels of Calcium, Magnesium and Zinc Chloride 总被引:1,自引:0,他引:1
Preblended composites of semimembranosus and adductor muscles were stored 12h at 4°C with 2.0% NaCl, 0 or 0.05% CaCl2, MgCl2, or ZnCl2 and 0 or 0.4% sodium tripolyphosphate (STPP). Model systems were formulated to contain 30% fat (high fat; HF) or 10% fat (low fat; LF). Divalent salts lowered extract pH and ZnCl2 elicited the greatest reduction. At both fat levels, CaCl2 increased and ZnCl2 decreased protein solubility, compared to the control (p<0.05). Myosin was not detected in ZnCl2-treated HF and LF batters without STPP and in the presence of STPP, MgCl2 and ZnCl2 increased myosin concentration at both fat levels (p<0.05). Zinc chloride increased actin concentration in HF batters; whereas, MgCl2 decreased soluble actin in LF batters (p<0.05). Magnesium chloride (0.05%) increased soluble proteins in LF batters containing 0.4% STPP by increasing myosin extractability. 相似文献
86.
福州第四纪沉积物工程地质特征研究 总被引:3,自引:0,他引:3
本文将福州第四系划分为七组,研究了各级分布特征,物理力学性质,并从持力层的选择、基坑支护、地基处理等方面进行了工程对策研究分析 相似文献
87.
Jos M. Crdoba Miguel A. Avils María J. Sayagus María D. Alcal Francisco J. Gotor 《Journal of Alloys and Compounds》2009,482(1-2):349-355
The machinability of materials is a dynamic field with enormous implications in different industrial sectors because manufacturers are constantly looking for improvements that can increase the overall productivity. Manufacturers of cutting tool inserts need to develop products that can perform at higher speeds and last longer under increasingly rigorous operating conditions. It has been revealed that cermets may exhibit better properties and performances when solid solution of multiple hard compounds is added instead of a mixture of several binary ones. In this work, a mechanically induced self-sustaining reaction (MSR) is described as a suitable synthesis method to obtain a wide range of different new quaternary carbonitride systems by milling mixtures of elemental powders of transition metals and graphite in a nitrogen atmosphere. Characterization was carried out using X-ray powder diffraction, elemental analysis, energy dispersive X-ray analysis (EDX), scanning and transmission electron microscopy and electron diffraction (ED). 相似文献
88.
F. Galindo J.C. Lima S.V. Luis A.J. Parola F. Pina 《Advanced functional materials》2005,15(4):541-545
In this paper we report the encapsulation of the compound 4′,7‐dihydroxyflavylium in a water‐permeable crosslinked poly(2‐hydroxyethyl methacrylate) matrix. The water permeability of the polymer and its transparency allow the use of pH and light stimuli to attain different states on the network defined by the various chemical reactions (multistate/multifunctional system). Unlike in water, in the polymer the compound 4′,7‐dihydroxyflavylium encapsulated exhibits a thermal barrier between the cis‐ and trans‐chalcones, a necessary requirement to define a write–read–erase cycle. 相似文献
89.
Shigeru Okada Toetsu Shishido Takao Mori Kiyokata Iizumi Kunio Kudou Kazuo Nakajima 《Journal of Alloys and Compounds》2008,458(1-2):297-301
LEAlB14 (orthorhombic, Imam) (LE = Li, Mg) crystals were grown using metal salts (Li2CO3, LiF, LiI, MgO, MgF2, MgI2) and crystalline boron from a high-temperature aluminium metal flux. The growth conditions for growing LEAlB14 were established using the starting mixtures of B/LE = 2.0, and Al metal was added to each mixture at a mass ratio of 1:15–20. LEAlB14 crystals from the Al-self flux using metal salts could be obtained from all the different salts. The maximum dimensions of LiAlB14 and MgAlB14 crystals were approximately 18 and 12 mm for the crystals obtained from LiF and MgF2. The unit-cell parameters of as-grown LEAlB14 are as follows: for LiAlB14, obtained from LiF, a = 0.5846 (2) nm, b = 0.8144 (2) nm, c = 1.0355 (3) nm, V = 0.4930 (2) nm3: for MgAlB14, obtained from MgF2, a = 0.5845 (2) nm, b = 0.8114 (2) nm, c = 1.0330 (3) nm, V = 0.4899 (3) nm3. Microhardness, oxidation resistance and magnetic susceptibility of these materials are described in detail. 相似文献
90.
A. Nagashima 《International Journal of Thermophysics》1991,12(1):1-15
High-temperature fluids often show interesting behavior and have important industrial applications, however, their thermophysical properties are extremely difficult to measure. Sometimes there are no measuring methods available, despite the fact that the great industrial demand for data on these property data at high temperatures is intense in recent years. In the present paper, five examples of approaches to measure transport properties of high temperature fluids are described. They include measurements of the viscosity of high-temperature melts by the oscillating-cup method, of the viscosity of vapors of H2O and D2O by the capillary method, of the thermal conductivity of molten salts by the transient hot-wire method, and of the thermal diffusivity by the optical method and of the thermal conductivity of high temperature gases by the shocktube method. 相似文献