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21.
铜材表面化学抛光工艺研究 总被引:2,自引:0,他引:2
为满足铜材钝化时对于处理表面的要求,本文系统地研究了多种化学抛光液配方与工艺,并对其中效果较好的两种进行了较深入研究,进而提出了可获得最佳表面抛光效果的配方与工艺. 相似文献
22.
二元函数的一个磨光算子 总被引:3,自引:0,他引:3
给出了一个新的二元函数磨光公式。与文[1]中所给出的逼近阶0(h^2+l^2)的公式相比较,逼近精度大大提高,在相同节点及计算量情形下,达到0(h^4+l^4)阶,具有保凸性质。 相似文献
23.
In this study, surface roughness of 304 stainless steel (304SS) varying from ca. 7 to 45 nm can be controlled by changing electropolishing variables in glycerol-containing baths. On the basis of the adsorbate-acceptor mechanism and the model for preferential adsorption of shielding molecules, incorporating the molecular interaction concept is helpful to explain the interactive effects of glycerol content, bath temperature, and current density on the surface roughness (Ra) and morphologies of 304SS. In order to easily understand how to control the surface roughness of 304SS in the glycerol-containing electrolyte, a simplified scheme integrating the above two mechanisms was proposed. From the atomic force microscopy (AFM) analyses, a rough surface is easily obtained by electropolishing at high bath temperatures, which endows the 304SS substrate with pores. 相似文献
24.
Five different varieties of paddy (four pigmented and one non-pigmented) were shelled and milled in pre and post parboiled form, their dietary fiber contents were estimated. Under similar conditions of milling, raw rice showed a high degree of polish (DOP), 9–12 g/100 g and parboiled rice showed low DOP, 4.6–6.6 g/100 g. Dietary fiber content was high in pigmented rice, 9–10 g/100 g compared to non-pigmented, ∼6 g/100 g. Soluble fiber content in pigmented head rice (dehusked) varied from 1 to 1.5 g/100 g and in its brokens varied from 0.45 to 1.45 g/100 g. Dietary fiber content was low by about 1% in parboiled rice. In the parboiled rice of pigmented varieties, the total fiber content varied from 7.95 ± 0.15 to 9.05 ± 0.25 g/100 g and the soluble fiber content varied from 0.7 to 0.9 g/100 g. In milled parboiled rice the respective values were 5 ± 0.4 to 6 ± 0.1 g/100 g and 0.85 ± 0.05 to 1.25 ± 0.05 g/100 g. However, the soluble fiber content in the non-pigmented brown rice, IR-64 remained same after parboiling, 0.75 ± 0.5 g/100 g. Milled parboiled rice showed higher soluble dietary fiber compared to milled raw rice. In conclusion, dietary fiber was high in pigmented rice varieties when compared with non-pigmented rice. 相似文献
25.
26.
Investigation into polishing process of CVD diamond films 总被引:1,自引:0,他引:1
A new technique used for polishing chemical vapor deposition (CVD) diamond films has been investigated, by which rough polishing of the CVD diamond films can be achieved efficiently. A CVD diamond film is coated with a thin layer of electrically conductive material in advance, and then electro-discharge machining (EDM) is used to machine the coated surface. As a result, peaks on the surface of the diamond film are removed rapidly. During machining, graphitization of diamond enables the EDM process to continue. The single pulse discharge shows that the material of the coated layer evidently affects removal behavior of the CVD diamond films. Compared with the machining of ordinary metal materials, the process of EDM CVD diamond films possesses a quite different characteristic. The removal mechanism of the CVD diamond films is discussed. 相似文献
27.
In this study, an electrolytic polishing experimental system was developed to obtain a uniform, flat-surfaced monocrystalline silicon with specific crystallographic planes. Several key factors reflecting specific electrolytic polishing on monocrystalline silicon with specific crystallographic planes were summarized. These factors, including electrolyte, conduction mode, Schottky barrier, semiconductor body resistance, and unidirectional conductivity, were analyzed comprehensively through energy spectrum analysis, theoretical modeling, and potential simulation. The effects of electrolytic polishing process were obtained, and corresponding solutions were proposed. Finally, the electrolytic polishing experiment for monocrystalline silicon with specific crystallographic planes was conducted. A uniform, flat-surfaced monocrystalline silicon with no metamorphic layer was then obtained. The flatness error of the center area was less than 0.201 µm. Furthermore, the crystallographic planes of monocrystalline silicon wafers showed no change. 相似文献
28.
29.
高精度光学表面的OFHC铜反射镜抛光技术 总被引:1,自引:0,他引:1
已研制出用于红外波段光辐射的特殊光样品-高精度光学表质量的无氧高导铜平面板射镜。本文描述了此种铜镜基底的抛光技术。讨论了材料的选择,基底成形精度及抛光工艺研究,给出了最终光学表面的测量结果。 相似文献
30.
Thus far, no any effective countermeasure against plating-induced poor uniformity exists in the global packaging market. In this paper, we aim to develop an effective polishing process to improve the poor uniformity existing in advanced double-layer copper pillars. After polishing, the wafer and chip uniformities of copper pillars could be reduced from the original values of 6.8-3.5% and 2.9-0.9%; after reflow, the wafer and chip uniformities of copper pillars reached 3.0% and 1.7%. Excellent uniformity in copper pillars ensures accurate joints, good reliability, high yields, and flexible layouts. 相似文献