全文获取类型
收费全文 | 165篇 |
免费 | 11篇 |
专业分类
电工技术 | 6篇 |
化学工业 | 34篇 |
金属工艺 | 5篇 |
机械仪表 | 7篇 |
建筑科学 | 4篇 |
能源动力 | 9篇 |
轻工业 | 19篇 |
水利工程 | 9篇 |
石油天然气 | 8篇 |
无线电 | 15篇 |
一般工业技术 | 28篇 |
冶金工业 | 9篇 |
自动化技术 | 23篇 |
出版年
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 8篇 |
2020年 | 3篇 |
2019年 | 7篇 |
2018年 | 5篇 |
2017年 | 7篇 |
2016年 | 8篇 |
2015年 | 6篇 |
2014年 | 4篇 |
2013年 | 15篇 |
2012年 | 5篇 |
2011年 | 17篇 |
2010年 | 7篇 |
2009年 | 11篇 |
2008年 | 4篇 |
2007年 | 6篇 |
2006年 | 7篇 |
2005年 | 6篇 |
2004年 | 5篇 |
2003年 | 5篇 |
2002年 | 3篇 |
2001年 | 3篇 |
1999年 | 2篇 |
1998年 | 4篇 |
1997年 | 2篇 |
1995年 | 3篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1992年 | 3篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1985年 | 1篇 |
1981年 | 1篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 3篇 |
排序方式: 共有176条查询结果,搜索用时 328 毫秒
61.
I. H. Olcay Unver 《国际水资源开发杂志》1997,13(2):187-208
The Republic of Turkey has initiated a comprehensivesocioeconomic development project in its less developed south-east region. The South-eastern Anatolia Project, or GAP to use its Turkish acronym, aims at improving the living standards of some 6 million residents of this 75 000 km2 region by mobilizing the natural resources of this area for integrated development on a regional scale. GAP is planned, designed, coordinated and implemented in an integrated manner taking into account interactions among different sectors as well as activities within individual sectors. The South-eastern Anatolia Project, in its historical context, was formulated as a packageof water and land resources development projects in the 1970s, which was later transformed, in the early 1980s, to a multi-sectoral, socioeconomic regional developmentprogramme.A Regional Administration (GAP-RDA) was established in 1989 for the management of the programme.Sectors covered in the development programmesinclude irrigation, hydropower, agriculture, urban infrastructure, rural development, forestry, healthcare and education among others. The water resources programme of the US$32 billion project includes 22 dams, 19 hydropowerplants and irrigation of 1.7 million ha of land. This paper describes, in brief, the size, main features, financial aspects and the status of the integrated socioeconomic project in its general context thus forming the basis for operational as well as specific issues. It then attempts to provide an overall discussion of the sustainability framework for development in its different but highly interrelated facets. After establishing the main, global benefits the paper comments on the adverse, undesired impacts along with the measures adapted to mitigate them. The paper later describes, in more detail, environmental impact studies, their main findings and proposals related to watersheds and irrigation development with an emphasis on management and environmental health matters together with the measures taken. The paper concludes by emphasizing the commitment to sustainable development and to planning ahead rather than damage reduction, and the effort to integrate relevant and sometimes conflicting aspects rather than compromise. 相似文献
62.
63.
I. H. Olcay Unver 《国际水资源开发杂志》1997,13(4):453-484
The recognition of the great water potential of the Euphrates and Tigris Rivers in south-east Turkey led to plans for their sustainable development for irrigation and hydropower generation and to control floods and droughts. This integrated socioeconomic developmentproject, called the Southeastern Anatolia Project (GAP), is one of the largest of its kind in the world. The water resources development programme includes 22 dams, 19 hydropower plants and the irrigation network for 1.7 million ha of land. The US$32 billion project comprises not only water resources development projects, but also investments in all development-relatedsectors. 相似文献
64.
Sulfated Hydrogel Matrices Direct Mitogenicity and Maintenance of Chondrocyte Phenotype through Activation of FGF Signaling
下载免费PDF全文
![点击此处可从《Advanced functional materials》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Ece Öztürk Øystein Arlov Seda Aksel Ling Li David M. Ornitz Gudmund Skjåk‐Bræk Marcy Zenobi‐Wong 《Advanced functional materials》2016,26(21):3649-3662
Deciphering the roles of chemical and physical features of the extracellular matrix (ECM) is vital for developing biomimetic materials with desired cellular responses in regenerative medicine. Here, it is demonstrated that sulfation of biopolymers, mimicking the proteoglycans in native tissues, induces mitogenicity, chondrogenic phenotype, and suppresses catabolic activity of chondrocytes, a cell type that resides in a highly sulfated tissue. Through tunable modification of alginate it is shown that increased sulfation of the microenvironment promotes fibroblast growth factor (FGF) signaling‐mediated proliferation of chondrocytes in a 3D matrix independent of stiffness, swelling, and porosity. Furthermore, for the first time it is shown that a biomimetic hydrogel acts as a 3D signaling matrix to mediate a heparan sulfate/heparin‐like interaction between FGF and its receptor leading to signaling cascades inducing cell proliferation, cartilage matrix production, and suppression of dedifferentiation markers. Collectively, this study reveals important insights on mimicking the ECM to guide self‐renewal of cells via manipulation of distinct signaling mechanisms. 相似文献
65.
This study uses the oxygen uptake rate (OUR) measurement to measure toxicity effects of 2,4-dichlorophenoxyacetic acid (2,4-D) on activated sludges fed with the wastewater from a small domestic wastewater treatment plant and peptone-based synthetic wastewater. Two 2l lab-scale batch reactors were run in parallel with the same F/M ratios (0.4 mg COD per mg VSS per day) to assess the inhibition effects of 2,4-D concentrations between 25 and 75 mg l(-1) considering at least a 100% dilution rate, as compared with a pesticide industry effluent containing 20,000-40,000 mg l(-1) COD, reaches a central treatment plant. It was noted that the OUR was decreased to 15 and 30%, respectively, when adding 75 mg l(-1) of 2,4-D to the domestic and synthetic reactors. Meanwhile, the addition of 25 plus 50 mg l(-1) of 2,4-D in sequence to the domestic wastewater reactor did not significantly affect the OUR profile. The OUR-based inhibition definition has been used in this research since the OUR methods have been frequently used and cited in the literature to study toxicity effects. However, the origin of the sludge used in the testing is also important. Synthetic wastewater may simulate the toxicity studies but with a higher response than actual systems, since the microorganisms are considerably becoming substrate-selective. 相似文献
66.
ABSTRACT After preextraction with ethanol-benzene (1:2) in a Soxhlet apparatus Tunçbilek lignite was extracted with dioxane at 330°C in an autoclave at different pressures and for different exposure times. The extracts were fractionated and many of the compounds they contain were identified by gas chromatography/mass spectrometry. The formation and yields of these compounds are discussed in terms of the structure of the parent fuel and the mechanism of extraction. 相似文献
67.
Gonca Alak Sükriye Aras Hisar Olcay Hisar Hüseyin Genççelep 《European Food Research and Technology》2011,232(1):23-28
A study was carried out to determine the effect of vacuum packed (VP) and modified atmosphere (MAP) (100% CO2) packing, chitosan film and cling film (CF) wrapping on the formation of biogenic amines and trimethylamine (TMA) during
storage of Atlantic bonito (Sarda sarda) fillets at 4 °C. The biogenic amine contents generally increased in all treatments with increasing storage period. Significant
differences were found (p < 0.01) in the levels of cadaverine, tyramine and histamine among the four treatments but it was not detected significant
difference for putrescine, phenylethylamine and tryptamine in this level. Spermidine and spermine did not detect throughout
the storage period for all experimental conditions. The amine contents of Atlantic bonito were highest in stored in cling
film, followed by VP, MAP and chitosan film. 相似文献
68.
Serkan Günal DogÜan Gkhan Ece
mer Nezih Gerek 《Mechanical Systems and Signal Processing》2009,23(8):2658-2670
This paper presents a new approach to induction motor condition monitoring using notch-filtered motor current signature analysis (NFMCSA). Unlike most of the previous work utilizing motor current signature analysis (MCSA) using spectral methods to extract required features for detecting motor fault conditions, here NFMCSA is performed in time-domain to extract features of energy, sample extrema, and third and fourth cumulants evaluated from data within sliding time window. Six identical three-phase induction motors were used for the experimental verification of the proposed method. One healthy machine was used as a reference, while other five with different synthetic faults were used for condition detection and classification. Extracted features obtained from NFMCSA of all motors were employed in three different and popular classifiers. The proposed motor current analysis and the performance of the features used for fault detection and classification are examined at various motor load levels and it is shown that a successful induction motor condition monitoring system is developed. Developed system is also able to indicate the load level and the type of a fault in multi-dimensional feature space representation. In order to test the generality and applicability of the developed method to other induction motors, data acquired from another healthy induction motor with different number of poles and rated power is also incorporated into the system. In spite of the above difference, the proposed feature set successfully locates the healthy motor within the classification cluster of “healthy motors” on the feature space. 相似文献
69.
70.