全文获取类型
收费全文 | 5418篇 |
免费 | 282篇 |
国内免费 | 45篇 |
专业分类
电工技术 | 117篇 |
综合类 | 51篇 |
化学工业 | 1319篇 |
金属工艺 | 156篇 |
机械仪表 | 160篇 |
建筑科学 | 268篇 |
矿业工程 | 36篇 |
能源动力 | 344篇 |
轻工业 | 788篇 |
水利工程 | 43篇 |
石油天然气 | 79篇 |
武器工业 | 12篇 |
无线电 | 228篇 |
一般工业技术 | 807篇 |
冶金工业 | 511篇 |
原子能技术 | 48篇 |
自动化技术 | 778篇 |
出版年
2024年 | 18篇 |
2023年 | 46篇 |
2022年 | 135篇 |
2021年 | 199篇 |
2020年 | 137篇 |
2019年 | 153篇 |
2018年 | 207篇 |
2017年 | 223篇 |
2016年 | 225篇 |
2015年 | 195篇 |
2014年 | 249篇 |
2013年 | 507篇 |
2012年 | 289篇 |
2011年 | 358篇 |
2010年 | 317篇 |
2009年 | 258篇 |
2008年 | 246篇 |
2007年 | 227篇 |
2006年 | 161篇 |
2005年 | 104篇 |
2004年 | 141篇 |
2003年 | 139篇 |
2002年 | 161篇 |
2001年 | 96篇 |
2000年 | 83篇 |
1999年 | 70篇 |
1998年 | 147篇 |
1997年 | 102篇 |
1996年 | 55篇 |
1995年 | 47篇 |
1994年 | 60篇 |
1993年 | 46篇 |
1992年 | 25篇 |
1991年 | 16篇 |
1990年 | 22篇 |
1989年 | 19篇 |
1988年 | 16篇 |
1987年 | 11篇 |
1986年 | 12篇 |
1985年 | 26篇 |
1984年 | 20篇 |
1983年 | 17篇 |
1982年 | 22篇 |
1981年 | 21篇 |
1980年 | 17篇 |
1977年 | 13篇 |
1976年 | 23篇 |
1975年 | 9篇 |
1974年 | 11篇 |
1973年 | 6篇 |
排序方式: 共有5745条查询结果,搜索用时 0 毫秒
1.
Physically based simulation of human hair is a well studied and well known problem. But the “pure” physically based representation of hair (and other animation elements) is not the only concern of the animators, who want to “control” the creation and animation phases of the content. This paper describes a sketch-based tool, with which a user can both create hair models with different styling parameters and produce animations of these created hair models using physically and key frame-based techniques. The model creation and animation production tasks are all performed with direct manipulation techniques in real-time. 相似文献
2.
The alarm lists presented to control center operators are usually difficult to interpret. The authors present an expert system that processes the alarm lists in Portuguese control centers. This system makes an intelligent synthesis of the available information and presents it in a flexible and structured way. It uses an original approach to deal with temporal reasoning and real-time constraints. The system incorporates an explanation module that enables its use as a tutor for novice operators 相似文献
3.
4.
OM Takayanagui AA Castro e Silva RC Santiago NS Odashima VC Terra AM Takayanagui 《Canadian Metallurgical Quarterly》1996,54(4):557-564
Cysticercosis is a severe public health problem in several regions of Asia, Africa and Latin America. Epidemiologic studies based on the frequency of cases observed in specialized neurology, neurosurgery and computed tomography services, at autopsy and in seroepidemiologic studies do not permit the determination of the true prevalence of the disease in the population. The objective of the present study was to investigate the prevalence of cysticercosis by compulsory notification. The coefficient of prevalence was 54 cases/100,000 inhabitants in the municipality of Ribeir?o Preto. The results also indicated that cysticercosis is not under control in our region since 21% of cases presented the active form of the disease. Compulsory notification proved to be a valuable resource for the epidemiologic study of cysticercosis, also permitting the mapping of more affected areas for a better direction of prevention strategies. 相似文献
5.
A de Meester C Six P Henin C Scavée R Luwaert JM Chaudron 《Canadian Metallurgical Quarterly》1996,89(12):1673-1676
The authors report the case of a 32 year old woman who was shot with a shotgun. Acute inferior wall infarction was detected fortuitously on electrocardiography and coronary angiography showed occlusion of the right coronary artery with lead shot. The single coronary lesion, absence, of other cardiac complications (haemopericardium, cardiac perforation, ...) and the favourable outcome with conservative medical treatment has not been previously reported to the authors' knowledge. 相似文献
6.
In this study forecast of Turkey's net electricity energy consumption on sectoral basis until 2020 is explored. Artificial neural networks (ANN) is preferred as forecasting tool. The reasons behind choosing ANN are the ability of ANN to forecast future values of more than one variable at the same time and to model the nonlinear relation in the data structure. Founded forecast results by ANN are compared with official forecasts. 相似文献
7.
Herchang Ay JiinYuh JangJer-Nan Yeh 《International Journal of Heat and Mass Transfer》2002,45(20):4069-4078
An experimental study is performed using an infrared thermovision to monitor temperature distribution over a plate-fin surface inside the plate finned-tube heat exchangers. The differentiation of the temperature function is derived to determine the local convective heat transfer coefficients on the tested fin, using a local element lumped conduction equation included the convective effect on the boundaries with experimental data. It is disclosed that the infrared thermography is capable of rapidly detecting location and extent of transition and separation regions of the boundary layer over the whole surface of the tested models. Through the comparison of the test results on the strategy region of the in-line and staggered arrangements, it is more easy to understand or interpret the detailed dynamic phenomena of flow existed in the heat exchangers. In addition, the experimental results demonstrate that the averaged heat transfer coefficient of staggered configuration is 14-32% higher than that of in-lined configuration 相似文献
8.
石油系油浆与煤系闪蒸油的焦化性能——I.热解条件的影响 总被引:3,自引:2,他引:1
通过偏光显微镜观察了石油系油浆(LH)与煤系闪蒸油(SN)焦化后所得焦块的光学结构。结果表明,在较宽条件下两种原料单独焦化均得不到取向度高的流线型结构。将两种原料以一定比例混合后先热解丙焦化所得焦块的光学结构明显好于二者混合后直接焦化所得焦块的光学结构,其中LH和SN以3:2的重量比混合后在440℃、1MPa下热解3.5h然后再在530℃、1MPa下焦化8h所得焦块为具有较高取向度的流线型结构,适合于作为针状焦的起始原料。 相似文献
9.
10.
Isolation and preliminary characterization of Pichia pinus mutants insensitive to glucose repression
A new method for the isolation of glucose repression-insensitive mutants in the methylotrophic yeast Pichia pinus was developed. The method is based on screening of small suspension samples derived from 2-deoxyglucose-resistant colonies for alcohol oxidase activity. Alcohol oxidase activity was evaluated by determination of formaldehyde excreted by cells. Mutants with glucose non-repressible alcohol oxidase and catalase synthesis were obtained. All mutants grew poorly on D -xylose compared to the wild type, whereas growth on L -arabinose was similar to the wild type. Changes in the glucose transport system were suggested to be responsible for altered growth characteristics and defective glucose repression. 相似文献