首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   346篇
  免费   37篇
  国内免费   2篇
电工技术   2篇
综合类   4篇
化学工业   123篇
金属工艺   3篇
机械仪表   13篇
建筑科学   8篇
矿业工程   2篇
能源动力   12篇
轻工业   43篇
水利工程   2篇
石油天然气   2篇
无线电   31篇
一般工业技术   63篇
冶金工业   32篇
原子能技术   1篇
自动化技术   44篇
  2023年   8篇
  2022年   15篇
  2021年   32篇
  2020年   22篇
  2019年   24篇
  2018年   23篇
  2017年   16篇
  2016年   19篇
  2015年   18篇
  2014年   19篇
  2013年   20篇
  2012年   11篇
  2011年   16篇
  2010年   13篇
  2009年   11篇
  2008年   16篇
  2007年   5篇
  2006年   9篇
  2005年   13篇
  2004年   8篇
  2003年   7篇
  2002年   1篇
  2001年   2篇
  2000年   1篇
  1999年   2篇
  1998年   6篇
  1997年   4篇
  1996年   8篇
  1995年   2篇
  1994年   2篇
  1992年   2篇
  1991年   6篇
  1990年   1篇
  1989年   1篇
  1988年   1篇
  1986年   1篇
  1985年   2篇
  1984年   2篇
  1982年   1篇
  1981年   1篇
  1980年   1篇
  1978年   4篇
  1977年   1篇
  1976年   4篇
  1973年   1篇
  1971年   1篇
  1966年   1篇
  1962年   1篇
排序方式: 共有385条查询结果,搜索用时 22 毫秒
1.
Polyethylene terephthalate (PET) is the most widely used polymer in the world. For the first time, the laser-driven integration of aluminum nanoparticles (Al NPs) into PET to realize a laser-induced graphene/Al NPs/polymer composite, which demonstrates excellent toughness and high electrical conductivity with the formation of aluminum carbide into the polymer is shown. The conductive structures show an impressive mechanical resistance against >10000 bending cycles, projectile impact, hammering, abrasion, and structural and chemical stability when in contact with different solvents (ethanol, water, and aqueous electrolytes). Devices including thermal heaters, carbon electrodes for energy storage, electrochemical and bending sensors show this technology's practical application for ultra-robust polymer electronics. This laser-based technology can be extended to integrating other nanomaterials and create hybrid graphene-based structures with excellent properties in a wide range of flexible electronics’ applications.  相似文献   
2.
3.
Shrimp oil was encapsulated in nanoliposomes and fortified into skim milk. Shrimp oil nanoliposomes (SONL) were thermodynamically stable when added into skim milk at 10 mL 100 mL−1. Mild bitterness in fortified skim milk caused by the SONL was masked by adding β-glucan at various levels (0.05–0.2 g 100 mL−1). With the addition of SONL, fortified skim milk appeared more reddish in colour due to the presence of astaxanthin. Addition of β-glucan resulted in the increase in viscosity of the fortified milk by forming network of junction zones. During the storage of skim milk fortified with SONL and 0.1 g 100 mL−1 β-glucan at 4 °C for 15 days, no major quality changes took place. Simulated in vitro digestion studies revealed that 45.41 g 100 g−1 eicosapentaenoic acid (EPA) and 48.86 g 100 g−1 docosahexaenoic acid (DHA) from shrimp oil were bioaccessible for absorption in the gut after digestion.  相似文献   
4.
5.
In all over the world, herbal drugs are usually adulterated with similar species or varieties due to incorrect identification. Most of herbal products devoid purity and quality, therefore an attempt was carried out to identify plant species and authenticate its herbal drug products from Mentha suaveolens. Microscopy tools provide an excellent platform to identify plants at species level. In this study, microscopic and pharmacokinetic parameters of M. suaveolens were observed. Plant species were collected from high diverse areas of Northern Pakistan. Macro and micro‐morphology including palynology and anatomical features were analyzed to study M. suaveolens. Species characteristics were studied, while implementing microscopic techniques for the delimitation and identification of the species. Traditionally Mentha species are used to cure several diseases that is, digestive disorders, respiratory disorders. Micromorphology (stem, leaves, flowers structure, length etc.), palynology (shape, size of pollen etc.), and anatomical characters (types of stomata, epidermal cell shape, and trichomes) were studied. Micromorphology and anatomical characters were of great interest and significance to discuss the taxonomy of the species. Taxonomic characters were studied to characterize and authenticate the species. The aim of the present study is to observe in detail the taxonomic identification of the species in term of morphology, palynology, and foliar epidermal anatomy for the correct identification along with their medicinal uses in the area.  相似文献   
6.
Applied Intelligence - The genome of the novel coronavirus (COVID-19) disease was first sequenced in January 2020, approximately a month after its emergence in Wuhan, capital of Hubei province,...  相似文献   
7.
8.
Canolol‐enriched extracts obtained from the extraction of fluidized bed treated canola meal with supercritical carbon dioxide were added to high‐oleic canola oil in different concentrations (200, 500 and 750 mg/kg). After 30 h of deep‐fat frying, oils fortified with canolol‐enriched extracts showed a two to three times better frying performance in comparison to the commonly used antioxidants (TBHQ, 200 mg/kg; rosemary extract, 40 and 200 mg/kg) and a control without antioxidants with regards to the formation of di‐ and polymer triacylglycerols, total polar compounds, secondary degradation products (anisidine value) and the iodine value. The canolol‐enriched extracts were also able to slow down the degradation of α‐ and γ‐tocopherol during frying resulting in significant amounts of tocopherols after 30 h of frying in comparison to the other oils. The influence of the canolol‐enriched extracts indicated strongly concentration‐dependent performance. With increasing concentration of the extract, the thermal stability of the fortified oil was improved. The only disadvantage of the addition of the extracts was an increase in the initial acid value, but within the frying time, only oil fortified with 750 mg canolol‐enriched extract/kg reached the limit given in different countries.  相似文献   
9.
This paper focuses on implementation of space–time CE/SE scheme for computing the transport of a passive pollutant by a flow. The flow model comprises of the Saint-Venant system of shallow water equations and the pollutant propagation is described by a transport equation. The one-dimensional and two-dimensional flow equations are numerically investigated using the CE/SE scheme. A number of test problems are presented to check the accuracy and efficiency of the proposed scheme. The results of CE/SE scheme are compared with the central scheme. Both the schemes are found to be in close agreement. However, our proposed CE/SE scheme accurately captures shocks and discontinuous profiles.  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号