全文获取类型
收费全文 | 5886篇 |
免费 | 174篇 |
国内免费 | 8篇 |
专业分类
电工技术 | 45篇 |
综合类 | 3篇 |
化学工业 | 1002篇 |
金属工艺 | 150篇 |
机械仪表 | 114篇 |
建筑科学 | 240篇 |
矿业工程 | 7篇 |
能源动力 | 120篇 |
轻工业 | 465篇 |
水利工程 | 32篇 |
石油天然气 | 19篇 |
无线电 | 615篇 |
一般工业技术 | 1084篇 |
冶金工业 | 1538篇 |
原子能技术 | 45篇 |
自动化技术 | 589篇 |
出版年
2022年 | 37篇 |
2021年 | 57篇 |
2020年 | 44篇 |
2019年 | 44篇 |
2018年 | 69篇 |
2017年 | 68篇 |
2016年 | 89篇 |
2015年 | 71篇 |
2014年 | 98篇 |
2013年 | 251篇 |
2012年 | 178篇 |
2011年 | 207篇 |
2010年 | 167篇 |
2009年 | 194篇 |
2008年 | 217篇 |
2007年 | 186篇 |
2006年 | 161篇 |
2005年 | 159篇 |
2004年 | 133篇 |
2003年 | 153篇 |
2002年 | 122篇 |
2001年 | 124篇 |
2000年 | 142篇 |
1999年 | 138篇 |
1998年 | 377篇 |
1997年 | 265篇 |
1996年 | 204篇 |
1995年 | 166篇 |
1994年 | 131篇 |
1993年 | 138篇 |
1992年 | 77篇 |
1991年 | 72篇 |
1990年 | 95篇 |
1989年 | 96篇 |
1988年 | 71篇 |
1987年 | 74篇 |
1986年 | 59篇 |
1985年 | 98篇 |
1984年 | 93篇 |
1983年 | 74篇 |
1982年 | 75篇 |
1981年 | 89篇 |
1980年 | 71篇 |
1979年 | 66篇 |
1978年 | 42篇 |
1977年 | 86篇 |
1976年 | 76篇 |
1975年 | 50篇 |
1974年 | 42篇 |
1973年 | 60篇 |
排序方式: 共有6068条查询结果,搜索用时 15 毫秒
1.
Robert Brooke Manrico Fabretto Samuel Pering Eliza Switalska Lachlan Reeks Drew Evans Peter Murphy 《应用聚合物科学杂志》2015,132(26)
A study using three different pairs of electrochromic polymers (ECPs) synthesized onto plaques by means of a modified vapor phase polymerization (VPP) technique is presented. Restriction of the respective polymerization times, allowed both faster and slower polymerizing monomers to be controlled, and produced blended plaques with visually diffuse interfaces. The ECPs within the blended plaques retain their individual electrochromic behavior and when encapsulated into an electrochromic device, show outstanding optical switching performance with little degradation evident over 10,000 cycles, coupled with a switching time of the order of 1 second. Blends also allow multiple diffuse color changes within an electrochromic device, due to the difference in oxidation potentials of the individual ECPs, making them candidates for adaptive camouflage use. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42158. 相似文献
2.
Dr. Omer K. Rasheed Cassandra Buhl Dr. Jay T. Evans Dr. Kendal T. Ryter 《ChemMedChem》2021,16(8):1246-1251
Mincle agonists have been shown to induce inflammatory cytokine production, such as tumor necrosis factor-alpha (TNF) and promote the development of a Th1/Th17 immune response that might be crucial to development of effective vaccination against pathogens such as Mycobacterium tuberculosis. As an expansion of our previous work, a library of 6,6′-amide and sulfonamide α,α-d -trehalose compounds with various substituents on the aromatic ring was synthesized efficiently in good to excellent yields. These compounds were evaluated for their ability to activate the human C-type lectin receptor Mincle by the induction of cytokines from human peripheral blood mononuclear cells. A preliminary structure–activity relationship (SAR) of these novel trehalose diamides and sulfonamides revealed that aryl amide-linked trehalose compounds demonstrated improved activity and relatively high potency cytokine production compared to the Mincle ligand trehalose dibehenate adjuvant (TDB) and the natural ligand trehalose dimycolate (TDM) inducing dose-dependent and human-Mincle-specific stimulation in a HEK reporter cell line. 相似文献
3.
This paper describes the methodology for simulating a reprographic ink with a ceramic ink based on a commercially available zirconia powder for direct ceramic ink-jet printing. Of over-riding importance was matching viscosity and this was tested systematically by using a mineral oil–hexane binary system. Of secondary importance was adjustment of the pressure defect behind the nozzle to compensate for small differences in surface tension. The inks tested in the wide array print-head were based on low electrical conductivity liquids to avoid damage to the electroding system. The organic binder for the zirconia ink was paraffin wax and the dispersant was a hydroxystearic acid based polyester. 相似文献
4.
DC Reynolds CE Leak KK Bajaj CE Stutz RL Jones KR Evans PW Yu WM Theis 《Canadian Metallurgical Quarterly》1989,40(9):6210-6217
5.
Geoffrey M. Eggert Paul R. Dawson Kapil K. Mathur 《International journal for numerical methods in engineering》1991,31(6):1031-1054
A forming model based on a viscoplastic flow formulation is derived which includes the effects of small elastic strains. A significant feature of the formulation is its reliance on the dominant inelastic material characteristics in the formation of the stiffness matrix for large strain problems. The resultant non-linear system of equations is solved by an adaptive descent method which combines the rapid convergence of Newton's method near the solution with the robustness of a method of successive approximations. The use of the adaptive descent method effectively extends the viscoplastic flow formulations into the nearly rate-insensitive range of behaviours exhibited, for example, by metals at low temperature, where slow convergence of the non-linear solution algorithm has traditionally hampered their use. 相似文献
6.
7.
R. Morena P. E. Lockwood L. Evans C. W. Fairhurst 《Journal of the American Ceramic Society》1986,69(4):75-C-
The effect on mechanical behavior of ZrO2 additions to a dental porcelain was investigated. The ZrO2 was introduced into the glassy matrix phase of the porcelain by refritting the all-glass porcelain constituent. X-ray diffraction indicated that a sizeable fraction of the ZrO2 was retained in the tetragonal form after the porcelain was fired. Zirconia additions to the porcelain produced substantial improvements in fracture toughness, strength, and thermal shock resistance. 相似文献
8.
9.
10.
Evans Jonathan St. B. T.; Handley Simon J.; Over David E. 《Canadian Metallurgical Quarterly》2003,29(2):321
The authors report 3 experiments in which participants were invited to judge the probability of statements of the form if p then q given frequency information about the cases pq, p?q, ?pq, and ?p?q (where ? = not). Three hypotheses were compared: (a) that people equate the probability with that of the material conditional, 1 - P(p?q); (b) that people assign the conditional probability, P(q/p); and (c) that people assign the conjunctive probability P(pq). The experimental evidence allowed rejection of the 1st hypothesis but provided some support for the 2nd and 3rd hypotheses. Individual difference analyses showed that half of the participants used conditional probability and that most of the remaining participants used conjunctive probability as the basis of their judgments. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献