全文获取类型
收费全文 | 7008篇 |
免费 | 5篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 5篇 |
化学工业 | 43篇 |
金属工艺 | 2篇 |
机械仪表 | 5篇 |
建筑科学 | 5篇 |
能源动力 | 2篇 |
轻工业 | 53篇 |
水利工程 | 1篇 |
石油天然气 | 2篇 |
无线电 | 21篇 |
一般工业技术 | 48篇 |
冶金工业 | 6790篇 |
原子能技术 | 2篇 |
自动化技术 | 35篇 |
出版年
2021年 | 4篇 |
2020年 | 3篇 |
2019年 | 5篇 |
2018年 | 4篇 |
2017年 | 4篇 |
2016年 | 3篇 |
2015年 | 2篇 |
2014年 | 4篇 |
2013年 | 8篇 |
2012年 | 10篇 |
2011年 | 7篇 |
2010年 | 10篇 |
2009年 | 14篇 |
2008年 | 6篇 |
2007年 | 14篇 |
2006年 | 13篇 |
2005年 | 6篇 |
2004年 | 15篇 |
2003年 | 21篇 |
2002年 | 4篇 |
2001年 | 8篇 |
2000年 | 7篇 |
1999年 | 221篇 |
1998年 | 2315篇 |
1997年 | 1294篇 |
1996年 | 820篇 |
1995年 | 424篇 |
1994年 | 339篇 |
1993年 | 421篇 |
1992年 | 44篇 |
1991年 | 49篇 |
1990年 | 58篇 |
1989年 | 48篇 |
1988年 | 57篇 |
1987年 | 57篇 |
1986年 | 58篇 |
1985年 | 38篇 |
1984年 | 2篇 |
1983年 | 18篇 |
1982年 | 25篇 |
1981年 | 31篇 |
1980年 | 61篇 |
1979年 | 4篇 |
1978年 | 14篇 |
1977年 | 141篇 |
1976年 | 283篇 |
1975年 | 12篇 |
1973年 | 2篇 |
1955年 | 3篇 |
1930年 | 1篇 |
排序方式: 共有7014条查询结果,搜索用时 15 毫秒
101.
The iron-chelating agent desferrioxamine now finds extensive use in the treatment and diagnosis of aluminum-related diseases in renal patients. We review the chemistry and pharmacokinetics of desferrioxamine in chelation therapy for patients on hemodialysis. 相似文献
102.
Automation of the wet sieving process in an instrument for particle size analysis is described. A powder is consecutively subjected to three sieves of any selected meshes from 38 μm up and the resulting fractions are collected individually, including both the undersize and oversize, in a submerged filter. The initial filter weight and the weights of all collected fractions are determined separately and stored in the microcomputer memory. Upon completion of an analysis, the sieved fraction weights are recalled, the total sample weight is calculated, and results are presented as weight per cent. Completion of each sieving step is established by filter weight constancy according to prearranged programming. Upon completion of an analysis, the system backwashes the filter and re-establishes conditions for the next analysis. Tests for accuracy with a standard material and repeated testing for short and long-term reproducibility are included. Applicability to a variety of powders is demonstrated. 相似文献
103.
KA Keay LJ Crowfoot NS Floyd LA Henderson MJ Christie R Bandler 《Canadian Metallurgical Quarterly》1997,762(1-2):61-71
Differentiating the binding properties of applied lectins should facilitate the selection of lectins for characterization of glycoreceptors on the cell surface. Based on the binding specificities studied by inhibition assays of lectin-glycan interactions, over twenty Gal and/or GalNAc specific lectins have been divided into eight groups according to their specificity for structural units (lectin determinants), which are the disaccharide as all or part of the determinants and of GalNAc alpha 1-->Ser (Thr) of the peptide chain. A scheme of codes for lectin determinants is illustrated as follows: (1) F (GalNAc alpha 1-->3GalNAc), Forssman specific disaccharide--Dolichos biflorus (DBL), Helix pomatia (HPL) and Wistaria floribunda (WFL) lectins. (2) A (GalNAc alpha 1-->3 Gal), blood group A specific disaccharide--Codium fragile subspecies tomentosoides (CFT), Soy bean (SBL), Vicia villosa-A4 (VVL-A4), and Wistaria floribunda (WFL) lectins. (3) Tn (GalNAc alpha 1-->Ser (Thr) of the protein core)--Vicia villosa B4 (VVL-B4), Salvia sclarea (SSL), Maclura pomifera (MPL), Bauhinia purpurea alba (BPL) and Artocarpus integrifolia (Jacalin, AIL). (4) T (Gal beta 1-->3GalNAc), the mucin type sugar sequences on the human erythrocyte membrane(T alpha), T antigen or the disaccharides at the terminal nonreducing end of gangliosides (T beta)--Peanut (PNA), Bauhinia purpurea alba (BPL), Maclura pomifera (MPL), Sophora japonica (SJL), Artocarpus lakoocha (Artocarpin) lectins and Abrus precatorius agglutinin (APA).(5) I and II (Gal beta 1-->3(4)GlcNAc)--the disaccharide residue at the nonreducing end of the carbohydrate chains derived from either N- or O-glycosidic linkage--Ricinus communis agglutinin (RCA1), Datura stramonium (TAL, Thorn apple), Erythrina cristagalli (ECL, Coral tree), and Geodia cydonium (GCL). (6) B (Gal alpha 1-->3Gal), human blood group B specific disaccharide--Griffonia(Banderiaea) simplicifolia B4 (GSI-B4). (7) E (Gal alpha 1-->4Gal), receptors for pathogenic E. coli agglutinin, Shiga toxin and Mistletoe toxic lectin-I (ML-I) and abrin-a. 相似文献
104.
A Lange M Walayat CM Turnbull P Palka P Mankad GR Sutherland MJ Godman 《Canadian Metallurgical Quarterly》1997,78(4):382-389
The properties of chemically cured and light-cured composite resins were recorded at baseline and at intervals over seven years, while the materials were exposed to controlled storage conditions as well as to various conditions typical of clinical situations. For chemically cured resins in clinical conditions, mechanical properties decreased, and working and setting times increased over four years; if refrigerated (controlled), properties remained constant past seven years. For light-cured resins, test results were constant over the entire seven-year test period regardless of storage conditions. An accelerated aging protocol was developed to allow for the evaluation of the relative storage stability of new and similar materials. 相似文献
105.
106.
107.
108.
109.
110.