全文获取类型
收费全文 | 703篇 |
免费 | 6篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 18篇 |
化学工业 | 172篇 |
金属工艺 | 84篇 |
机械仪表 | 30篇 |
建筑科学 | 6篇 |
矿业工程 | 3篇 |
轻工业 | 27篇 |
水利工程 | 8篇 |
石油天然气 | 60篇 |
武器工业 | 4篇 |
无线电 | 38篇 |
一般工业技术 | 119篇 |
冶金工业 | 100篇 |
原子能技术 | 31篇 |
自动化技术 | 12篇 |
出版年
2022年 | 18篇 |
2021年 | 29篇 |
2020年 | 15篇 |
2019年 | 13篇 |
2018年 | 16篇 |
2017年 | 25篇 |
2016年 | 32篇 |
2015年 | 8篇 |
2014年 | 18篇 |
2013年 | 24篇 |
2012年 | 21篇 |
2011年 | 31篇 |
2010年 | 20篇 |
2009年 | 20篇 |
2008年 | 25篇 |
2007年 | 33篇 |
2006年 | 20篇 |
2005年 | 13篇 |
2004年 | 18篇 |
2003年 | 14篇 |
2002年 | 11篇 |
2000年 | 16篇 |
1999年 | 8篇 |
1998年 | 13篇 |
1997年 | 12篇 |
1996年 | 13篇 |
1995年 | 6篇 |
1993年 | 11篇 |
1992年 | 6篇 |
1991年 | 7篇 |
1990年 | 8篇 |
1989年 | 7篇 |
1987年 | 10篇 |
1986年 | 9篇 |
1985年 | 7篇 |
1983年 | 7篇 |
1981年 | 6篇 |
1980年 | 6篇 |
1979年 | 7篇 |
1978年 | 8篇 |
1977年 | 8篇 |
1976年 | 17篇 |
1975年 | 6篇 |
1974年 | 6篇 |
1972年 | 5篇 |
1971年 | 7篇 |
1970年 | 10篇 |
1969年 | 9篇 |
1967年 | 6篇 |
1966年 | 6篇 |
排序方式: 共有712条查询结果,搜索用时 15 毫秒
21.
V. V. Grib I. M. Petrova A. N. Romanov 《Journal of Machinery Manufacture and Reliability》2016,45(5):433-437
This study considers the general model of estimating changes in technical state of mechanical systems caused by external action. This model makes it possible to estimate their effect on the probability of breakdowns. The considered examples include the destruction probabilities for crank rods of the opposite compressor to be simultaneously affected by cyclical loading and wear. 相似文献
22.
23.
V. M. Samoilenko R. G. Ravilov V. V. Drevnyak M. A. Petrova 《Russian Metallurgy (Metally)》2016,2016(6):555-558
The fracture mechanism of the thermal barrier coating of gas turbine blades is studied. The causes of the fracture of the ceramic layer are discussed and the possible ways to increase the fatigue life of the thermal barrier coating are considered. 相似文献
24.
25.
26.
The mechanochemical solid-phase reactions of humic acid with Cu2+, Ni2+, and Cd2+ metal ions were studied. The analysis of the mineral composition of humic acids by atomic emission spectrometry showed an increase in the concentrations of Cu2+, Ni2+, and Cd2+ ions after mechanical treatment. 相似文献
27.
Andrey S. Erst Alexander A. Chernonosov Natalia V. Petrova Maxim S. Kulikovskiy Svetlana Yu. Maltseva Wei Wang Vera A. Kostikova 《International journal of molecular sciences》2022,23(1)
Aqueous-ethanol extracts (70%) from the leaves of Eranthis longistipitata Regel. (Ranunculaceae Juss.)—collected from natural populations of Kyrgyzstan—were studied by liquid chromatography with high-resolution mass spectrometry (LC-HRMS). There was no variation of the metabolic profiles among plants that were collected from different populations. More than 160 compounds were found in the leaves, of which 72 were identified to the class level and 58 to the individual-compound level. The class of flavonoids proved to be the most widely represented (19 compounds), including six aglycones [quercetin, kaempferol, aromadendrin, 6-methoxytaxifolin, phloretin, and (+)-catechin] and mono- and diglycosides (the other 13 compounds). In the analyzed samples of E. longistipitata, 14 fatty acid–related compounds were identified, but coumarins and furochromones that were found in E. longistipitata were the most interesting result; furochromones khelloside, khellin, visnagin, and cimifugin were found in E. longistipitata for the first time. Coumarins 5,7-dihydroxy-4-methylcoumarin, scoparone, fraxetin, and luvangetin and furochromones methoxsalen, 5-O-methylvisammioside, and visamminol-3′-O-glucoside were detected for the first time in the genus Eranthis Salisb. For all the above compounds, the structural formulas are given. Furthermore, detailed information (with structural formulas) is provided on the diversity of chromones and furochromones in other representatives of Eranthis. The presence of chromones in plants of the genus Eranthis confirms its closeness to the genus Actaea L. because chromones are synthesized by normal physiological processes only in these members of the Ranunculaceae family. 相似文献
28.
29.
Dresvyannikov A. F. Petrova E. V. Khairullina A. I. 《Protection of Metals and Physical Chemistry of Surfaces》2020,56(1):89-93
Protection of Metals and Physical Chemistry of Surfaces - Based on the use of electrogenerated reactants, a method for producing Al2O3–ZrO2–MgO oxide systems has been proposed. Their... 相似文献
30.
Yordanka Gluhcheva Irena Pashkunova-Martic Martin Schaier Ivelin Vladov Silviya Stoykova Emilia Petrova Ekaterina Pavlova Peter Dorkov Thomas H. Helbich Bernhard Keppler Juliana Ivanova 《International journal of molecular sciences》2022,23(8)
Lead (Pb) exposure induces severe nephrotoxic effects in humans and animals. Herein, we compare the effects of two chelating agents, salinomycin and deferiprone, on Pb-induced renal alterations in mice and in the homeostasis of essential elements. Adult male mice (Institute of Cancer Research (ICR)) were randomized into four groups: control (Ctrl)—untreated mice administered distilled water for 28 days; Pb-exposed group (Pb)—mice administered orally an average daily dose of 80 mg/kg body weight (BW) lead (II) nitrate (Pb(NO3)2) during the first two weeks of the experimental protocol followed by the administration of distilled water for another two weeks; salinomycin-treated (Pb + Sal) group—Pb-exposed mice, administered an average daily dose of 16 mg/kg BW salinomycin for two weeks; deferiprone-treated (Pb + Def) group—Pb-exposed mice, administered an average daily dose of 20 mg/kg BW deferiprone for 14 days. The exposure of mice to Pb induced significant accumulation of the toxic metal in the kidneys and elicited inflammation with leukocyte infiltrations near the glomerulus. Biochemical analysis of the sera revealed that Pb significantly altered the renal function markers. Pb-induced renal toxicity was accompanied by a significant decrease in the endogenous renal concentrations of phosphorous (P), calcium (Ca), copper (Cu) and selenium (Se). In contrast to deferiprone, salinomycin significantly improved renal morphology in Pb-treated mice and decreased the Pb content by 13.62% compared to the Pb-exposed group. There was also a mild decrease in the renal endogenous concentration of magnesium (Mg) and elevation of the renal concentration of iron (Fe) in the salinomycin-treated group compared to controls. Overall, the results demonstrated that salinomycin is a more effective chelating agent for the treatment of Pb-induced alterations in renal morphology compared to deferiprone. 相似文献