全文获取类型
收费全文 | 1253篇 |
免费 | 90篇 |
专业分类
电工技术 | 6篇 |
综合类 | 4篇 |
化学工业 | 423篇 |
金属工艺 | 18篇 |
机械仪表 | 22篇 |
建筑科学 | 53篇 |
能源动力 | 17篇 |
轻工业 | 162篇 |
水利工程 | 11篇 |
石油天然气 | 1篇 |
无线电 | 61篇 |
一般工业技术 | 212篇 |
冶金工业 | 211篇 |
自动化技术 | 142篇 |
出版年
2024年 | 1篇 |
2023年 | 20篇 |
2022年 | 54篇 |
2021年 | 92篇 |
2020年 | 45篇 |
2019年 | 45篇 |
2018年 | 36篇 |
2017年 | 43篇 |
2016年 | 36篇 |
2015年 | 52篇 |
2014年 | 40篇 |
2013年 | 74篇 |
2012年 | 80篇 |
2011年 | 101篇 |
2010年 | 75篇 |
2009年 | 67篇 |
2008年 | 83篇 |
2007年 | 70篇 |
2006年 | 56篇 |
2005年 | 34篇 |
2004年 | 40篇 |
2003年 | 35篇 |
2002年 | 26篇 |
2001年 | 23篇 |
2000年 | 16篇 |
1999年 | 11篇 |
1998年 | 19篇 |
1997年 | 11篇 |
1996年 | 8篇 |
1995年 | 5篇 |
1994年 | 1篇 |
1993年 | 5篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 3篇 |
1988年 | 7篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 6篇 |
1984年 | 1篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1979年 | 1篇 |
1976年 | 3篇 |
1975年 | 2篇 |
1973年 | 1篇 |
排序方式: 共有1343条查询结果,搜索用时 15 毫秒
51.
Maurits Kaptein Deonne Castaneda Nicole Fernandez Clifford Nass 《Journal of Computer-Mediated Communication》2014,19(3):342-357
The feeling of connectedness experienced in computer‐mediated relationships can be explained by the similarity‐attraction effect (SAE). Though SAE is well established in psychology, the effects of some types of similarity have not yet been explored. In 2 studies, we demonstrate similarity‐attraction based on the timing of activities—“when‐similarity.” We describe a novel experimental paradigm for manifesting when‐similarity while controlling for the activities being performed (what‐similarity). Study 1 (N = 24) shows when‐similarity attraction in the evaluation of connectedness with others. Study 2 (N = 42) identifies an interaction between who‐similarity—similarity in personal backgrounds—and when‐similarity. Both studies show that real‐time computer‐mediated interaction can lead to greater feelings of connectedness between people when there is an opportunity to discover when‐similarity. 相似文献
52.
53.
Joao Henrique da Silva Rego ;Antonio Alberto Nepomucenol ;Enio Pazini Figueiredo ;Nicole Pagan Hasparyk 《土木工程与建筑:英文版》2014,(11):1396-1402
In several countries, the residual RHA (rice husk ash) has been produced in rice processing industries or in thermoelectric plants that use rice husk to generate heat and/or electrical energy, usually without burning process control. This causes a reduction in the amorphous silica content of residual RHA, which distinguishes them from the RHA produced according to controlled burning process, which is totally amorphous and considered a highly reactive pozzolan. In this paper, the hydration products and the porous structure of binders paste were studied by replacing, in weight of 5%, 10% and 20% of Portland cement OPC (ordinary Portland cement), by residual RHAs named A and B, which have high and low content of amorphous silica, respectively, using microstructure evaluation techniques as XRD (X-ray diffraction), TG (thermogravimetric) tests and MIP (mercury intrusion porosimetry). A reducing the size of the pores of the pastes was observed according to the increase of content replacement of RHA A and RHA B. 相似文献
54.
55.
56.
How Modifying Third‐Party Information Affects Interpersonal Impressions and the Evaluation of Collaborative Online Media
下载免费PDF全文
![点击此处可从《The Journal of communication》网站下载免费的PDF全文](/ch/ext_images/free.gif)
David C. DeAndrea Brandon Van Der Heide Nicole Easley 《The Journal of communication》2015,65(1):62-78
Previous research has drawn upon warranting theory to help explain how viewers evaluate people and entities online. Extending previous research, this study assesses how the ability of a target to modify third‐party information affects perceptions of warranting value, and in turn, interpersonal impressions and the perceived legitimacy of online media that host evaluations. Additionally, this work explores how the perceived objectivity of a third‐party evaluator affects impressions in online settings. The results provide support for warranting theory and help clarify how impressions are formed in online environments when people have the ability to generate and modify content collectively. The theoretical implications this study has for warranting theory and future research directions are discussed. 相似文献
57.
The purpose of the study was to obtain a composite material with the self‐reinforced structure, which processing provide increased mechanical properties. The composites used in presented work were prepared from the two types of fiber mixtures, both were based on polypropylene fibers, the difference was in used cellulose or wood flour filler. Composites were prepared using the hot compaction method. The presented research describes the effect of the composite composition and processing conditions. The results include the static tension measurements, tensile impact tests and thermal analysis, including: DSC and DMTA. The structure has been studies using the SEM observations. Results of presented studies confirm the self‐reinforcing effect in obtained hybrid composites. It provides in the comparison to the standard wood polymer composites to the higher level of material reinforcement with lower amount of natural filler. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43283. 相似文献
58.
Kai Xu Pavel Hrma Jarrett A. Rice Michael J. Schweiger Brian J. Riley Nicole R. Overman Albert A. Kruger 《Journal of the American Ceramic Society》2016,99(9):2964-2970
The feed‐to‐glass conversion, which comprises complex chemical reactions and phase transitions, occurs in the cold cap during nuclear waste vitrification. To investigate the conversion process, we analyzed heat‐treated samples of a simulated high‐level waste feed using X‐ray diffraction, electron probe microanalysis, leaching tests, and residual anion analysis. Feed dehydration, gas evolution, and borate phase formation occurred at temperatures below 700°C before the emerging glass‐forming melt was completely connected. Above 700°C, intermediate aluminosilicate phases and quartz particles gradually dissolved in the continuous borosilicate melt, which expanded with transient foam. Knowledge of the chemistry and physics of feed‐to‐glass conversion will help us control the conversion path by changing the melter feed makeup to maximize the glass production rate. 相似文献
59.
60.
Tomasz Przepiora Donata Figaj Aleksandra Bogucka Jakub Fikowicz-Krosko Robert Czajkowski Nicole Hugouvieux-Cotte-Pattat Joanna Skorko-Glonek 《International journal of molecular sciences》2022,23(2)
In bacteria, the DsbA oxidoreductase is a crucial factor responsible for the introduction of disulfide bonds to extracytoplasmic proteins, which include important virulence factors. A lack of proper disulfide bonds frequently leads to instability and/or loss of protein function; therefore, improper disulfide bonding may lead to avirulent phenotypes. The importance of the DsbA function in phytopathogens has not been extensively studied yet. Dickeya solani is a bacterium from the Soft Rot Pectobacteriaceae family which is responsible for very high economic losses mainly in potato. In this work, we constructed a D. solani dsbA mutant and demonstrated that a lack of DsbA caused a loss of virulence. The mutant bacteria showed lower activities of secreted virulence determinants and were unable to develop disease symptoms in a potato plant. The SWATH-MS-based proteomic analysis revealed that the dsbA mutation led to multifaceted effects in the D. solani cells, including not only lower levels of secreted virulence factors, but also the induction of stress responses. Finally, the outer membrane barrier seemed to be disturbed by the mutation. Our results clearly demonstrate that the function played by the DsbA oxidoreductase is crucial for D. solani virulence, and a lack of DsbA significantly disturbs cellular physiology. 相似文献