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排序方式: 共有495条查询结果,搜索用时 15 毫秒
41.
目前,稀土在化纤类,毛类纺织品染色中的应用比较成熟,而在棉类染色中的应用还未能得到推广,探讨稀土在直接染料对人棉灯芯绒织物染色中的作用机理,并从试验和生产方面加以比较,总结出本厂的成熟工艺。作者认为稀土对人棉灯芯绒织物在直接染料染色上应用是切实可行的,效果是理想的。 相似文献
42.
Qingbei Li Jianming Lin Jihuai Wu Zhang Lan Yue Wang Fuguo Peng Miaoliang Huang 《Electrochimica acta》2011,(14):4980
In order to increase of the photocurrent, photovoltage and energy conversion efficiency of dye-sensitized solar cell (DSSC), rare-earth doped oxide of Lu2O3:(Tm3+, Yb3+) is prepared and introduced into the TiO2 film in the DSSC. As a luminescence medium, Lu2O3:(Tm3+, Yb3+) improves incident light harvest via a conversion luminescence process and increases photocurrent; as a p-type dopant, the rare-earth ions elevate the energy level of the oxide film and increase the photovoltage. Under a simulated solar light irradiation of 100 mW cm−2, the light-to-electric energy conversion efficiency of the DSSC with Lu2O3:(Tm3+, Yb3+) doping reaches 6.63%, which is increased by 11.1% compared to the DSSC without Lu2O3:(Tm3+, Yb3+) doping. 相似文献
43.
稀土固体超强酸SO4^2—/TiO2/La^3+催化合成丁酸丁酯 总被引:4,自引:0,他引:4
研究了以稀土固体超强酸SO4^2-/TiO2/La^3+为催化剂,丁酸和正丁醇为原料合成丁酸丁酯,并考察了影响反应4 因素。结果表明,醇酸物质的量比为1.8:1,催化剂用量为0.5g(本酸为0.2mol的情况下),带水剂甲苯为15mL,反应时间为2.0h是合成丁酸丁酯的较适宜的反应条件,酯化率达98.6%。 相似文献
44.
The rare-earth diiodides, MI2, may be synthesized from the corresponding triiodides, MI3, by reduction with their metals at elevated temperatures or, alternatively, through so-called metallothermic reduction reactions with alkaline or alkaline-earth metals. In these cases, ternary iodides may be obtained that may be derived from the binary diiodides by either formal addition or substitution. Prominent formula types that are thus obtained are AIMI3, or the mixed-valent AI5MII2MIIII12 and AIIMI4 with AI and AII representing alkaline or alkaline-earth elements (and their analogues), respectively. Further iodides that are relevant in these systems are, for example, Pr2I5, Ba6Pr3I19 and interstitially stabilized phases such as {Er14(N2)(C2)2}I24, La9O4I16 and Ba{Ce4N2}I8. 相似文献
45.
稀土添加剂在硬质合金中的应用研究 总被引:9,自引:0,他引:9
对国内含稀土元素的硬质合金10多年来的研制情况及稀土元素对硬质合金组织和性能的影响进行了概述。 相似文献
46.
Yildirhan
ner 《Journal of Alloys and Compounds》2006,420(1-2):20-24
Electrical and magnetic properties of NdCuPb compound were investigated by means of electrical resistivity, magnetization measurements in the temperature range 1.5–100 K. Low-field dc susceptibility goes through a maximum at TN=13.2 K, indicating a paramagnetic to an antiferromagnetic transition and then follows a sharp peak at T=5.9 K. The susceptibility data exhibits a Curie–Weiss like behavior in the paramagnetic regime and the effective moment per neodium atom is found to be 3.62μB from the data at temperatures above 42 K. This value is exactly equal to that for Nd3+, while at lower temperatures, the data yields a little bit less than its free ion value. The ratio M/H versus temperature T curves for different values of the magnetic field split into multiple branches at about T=42 K due to crystalline field effects.In addition, electrical resistivity in a magnetic field up to 120 kOe was also measured in the same temperature range. The resistivity gives non-metallic behavior. The antiferromagnetic transition is clearly discern by a “Cr-like” anomaly at about 13 K, followed by a sharp increase in the resistivity (like a jump) at T=5.9 K where the susceptibility gives similar effect. On other hand, the magnetic contribution to the resistivity begins to decrease at T=42 K at which M/H curves merges. All these behavior may be attributed to crystal-field-splitting of neodium atoms’levels. 相似文献
47.
Crystal growth of rare-earth-doped ternary potassium lead chloride single crystals by the Bridgman method 总被引:1,自引:0,他引:1
High optical quality pure and rare-earth-doped ternary-potassium-lead-chloride (KPb2Cl5) single crystals have been grown using the Bridgman technique in a two-zone transparent vertical furnace. Combining the chlorination of the melt, to eliminate oxygen impurities, with a horizontal zone-refining, followed by the Bridgman growth itself using sealed silica ampoules, we successfully grew non-moisture-sensitive crystals of a high optical quality. The moisture content in the raw materials determines the quality of the resulting crystals. 相似文献
48.
49.
对1Cr18Ni12Mo2Ti奥氏体不锈钢在稀土催渗条件下进行了加与未加辅助铁板的离子硫氮共渗对比试验.试验表明:稀土具有很强的催渗作用.在与辅助铁板的共同作用下,可使奥氏体不锈钢的氮化温度降低60℃,减小了零件的变形;在相同的共渗温度条件下,可使氮化层深度比离子硫氮碳共渗增加30%以上,比未加辅助铁板的稀土离子硫氮碳增加10%.且稀土元素可渗入钢表层,细化渗层组织,促进氮碳化合物弥散细小析出,提高渗层硬度. 相似文献
50.
M. Palumbo G. Borzone S. Delsante N. Parodi G. Cacciamani R. Ferro L. Battezzati M. Baricco 《Intermetallics》2004,12(12):442-1372
An optimised set of thermodynamic parameters for the Ce–Ni system has been obtained using the CALPHAD approach. A thorough thermodynamic analysis of the system has been carried out using different calorimetric techniques and the data have been used in the assessment. The free energy of the liquid phase has been described as a function of temperature and composition using a Redlich–Kister polynomial. Solid compounds have been considered as stoichiometric with the exception of the Laves phases. The phase diagram and thermodynamic quantities calculated from assessed parameters agree well with experimental data. 相似文献