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   306篇
  免费   29篇
电工技术   4篇
综合类   1篇
化学工业   93篇
金属工艺   2篇
机械仪表   11篇
建筑科学   11篇
矿业工程   1篇
能源动力   17篇
轻工业   63篇
水利工程   3篇
无线电   19篇
一般工业技术   34篇
冶金工业   34篇
原子能技术   2篇
自动化技术   40篇
  2024年   4篇
  2023年   7篇
  2022年   9篇
  2021年   25篇
  2020年   19篇
  2019年   10篇
  2018年   26篇
  2017年   17篇
  2016年   17篇
  2015年   13篇
  2014年   22篇
  2013年   29篇
  2012年   13篇
  2011年   17篇
  2010年   19篇
  2009年   11篇
  2008年   11篇
  2007年   11篇
  2006年   7篇
  2005年   3篇
  2004年   4篇
  2003年   3篇
  2002年   1篇
  2000年   3篇
  1999年   2篇
  1998年   9篇
  1997年   9篇
  1996年   6篇
  1994年   1篇
  1993年   1篇
  1990年   1篇
  1988年   1篇
  1987年   1篇
  1981年   1篇
  1976年   2篇
排序方式: 共有335条查询结果,搜索用时 15 毫秒
121.
The objective of this study was to determine the in vitro inhibition effects of seven commonly used pesticides including 2,4-d-acid dimethylamine, fenoxaprop-p-ethyl, glyphosate isopropylamine, haloxyfop-p-methyl, cypermethrin, λ-cyhalothrin, and dichlorvos on the peroxidase purified from turnip (Brassica rapa L.) and black radish (Raphanus sativus L.) using 4-amino benzohydrazide affinity column chromatography. The purification factors for the turnip and black radish peroxidases were found to be 263.29-fold (with a yield of 12.89%) and 36.20-fold (with a yield of 6.90%), respectively. Among these compounds, λ-cyhalothrin showed the strongest inhibitory effect against turnip peroxidase (Ki: 1.23 × 10?2 ± 0.21 × 10?2 mM) as noncompetitive inhibition. On the other hand, cypermethrin demonstrated the highest inhibition effect against black radish peroxidase (Ki: 2.14 × 10?2 ± 0.08 × 10?2 mM) as competitive inhibition.  相似文献   
122.
Garlic in different forms has antioxidant properties. These properties are shown to be due to the existence of compounds such as water soluble organosulfur compounds, S-allylcysteine and lipid soluble compounds like diallyl sulfide. The in vivo and in vitro ischemia reperfusion studies showed that prophylactic administration of aqueous garlic prior to ischemia reperfusion inhibit lipid peroxidation and prevent depletion in glutathione through its compounds that led to functional recovery. Its ability to inhibit neutrophil migration could suppress fibrosis formation. These preventive effects are seen in models that studied organs such as kidney and liver with functional recovery. Organ system specific activity such as angiotensin converting enzyme-inhibiting activity contributes to a cardioprotective and blood pressure lowering effect. Future studies should focus on post ischemia reperfusion administration of garlic to explore its rescue potential rather than prophylactic impact. Bench research findings should be translated into clinical use through human studies.  相似文献   
123.
124.
In this study, different anthocyanin sources including grape skin, black carrot, and red cabbage were used to determine the effect of thermal treatment, different acidity levels, and time on the anthocyanin content and degradation. The total anthocyanin contents were modeled by neuro fuzzy inference system (ANFIS) and artificial neural network (ANN) models. The red cabbage anthocyanin stabilities were higher than others. The anthocyanins degraded more rapidly at higher temperatures. The anthocyanin contents of samples decreased with the increase of pH from 3 to 7. Comparison of the models showed that the ANFIS model performed better than the ANN model for the estimation of total anthocyanin content in all samples. The lowest root mean square error (0.0457) and highest R 2 (0.9942) values were obtained for red cabbage and grape skin in the validation period with the ANFIS model, respectively. This study showed that both models can be utilized efficiently for the prediction of total anthocyanin content affected by temperature, time, and pH.  相似文献   
125.
Antimicrobial edible films and coatings   总被引:2,自引:0,他引:2  
Increasing consumer demand for microbiologically safer foods, greater convenience, smaller packages, and longer product shelf life is forcing the industry to develop new food-processing, cooking, handling, and packaging strategies. Nonfluid ready-to-eat foods are frequently exposed to postprocess surface contamination, leading to a reduction in shelf life. The food industry has at its disposal a wide range of nonedible polypropylene- and polyethylene-based packaging materials and various biodegradable protein- and polysaccharide-based edible films that can potentially serve as packaging materials. Research on the use of edible films as packaging materials continues because of the potential for these films to enhance food quality, food safety, and product shelf life. Besides acting as a barrier against mass diffusion (moisture, gases, and volatiles), edible films can serve as carriers for a wide range of food additives, including flavoring agents, antioxidants, vitamins, and colorants. When antimicrobial agents such as benzoic acid, sorbic acid, propionic acid, lactic acid, nisin, and lysozyme have been incorporated into edible films, such films retarded surface growth of bacteria, yeasts, and molds on a wide range of products, including meats and cheeses. Various antimicrobial edible films have been developed to minimize growth of spoilage and pathogenic microorganisms, including Listeria monocytogenes, which may contaminate the surface of cooked ready-to-eat foods after processing. Here, we review the various types of protein-based (wheat gluten, collagen, corn zein, soy, casein, and whey protein), polysaccharide-based (cellulose, chitosan, alginate, starch, pectin, and dextrin), and lipid-based (waxes, acylglycerols, and fatty acids) edible films and a wide range of antimicrobial agents that have been or could potentially be incorporated into such films during manufacture to enhance the safety and shelf life of ready-to-eat foods.  相似文献   
126.
A variety of natural vinegar products are found in civilizations around the world. A review of research on these fermented products indicates numerous reports of health benefits derived by consumption of vinegar components. Therapeutic effects of vinegar arising from consuming the inherent bioactive components including acetic acid, gallic acid, catechin, ephicatechin, chlorogenic acid, caffeic acid, p‐coumaric acid, and ferulic acid cause antioxidative, antidiabetic, antimicrobial, antitumor, antiobesity, antihypertensive, and cholesterol‐lowering responses. The aims of this article are to discuss vinegar history, production, varieties, acetic acid bacteria, and functional properties of vinegars.  相似文献   
127.
Examined the process of acculturation with a specific emphasis on the impact of economic integration on psychological well-being and adaptation. 110 Turkish immigrants (aged 20–70 yrs) living in Montreal were surveyed through questionnaires. Despite high educational attainments, two-thirds of the sample were either unemployed or underemployed. Inability to fully integrate into the labor force in the 1st 6 mo in Canada was attributed mainly to lack of competence in both official languages, difficulty in getting credentials and accreditations recognized in Canada, and lack of Canadian work experience. In time, these barriers were overcome. In their place, market conditions (e.g., economic recession) delayed full participation in the work force. The model developed and tested through LISREL 8 demonstrated that adversity experienced in employment life, such as status loss, unemployment, and underemployment, had a negative impact on both psychological well-being and adaptation to Canada. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
128.
The purpose of this research was to determine the effects of different fat replacers on the sensory and texture attributes of vanillin‐flavored ice cream. Inulin is a fairly new fat replacer which has been proven to be a health promoter. Two vanilla ice cream formulations were produced using different ratios of inulin and Simplesse® as fat replacers to provide better flavor and textural properties. Aspartame and acesulfam‐K were used as sweeteners in the low‐calorie ice creams. Sensory and instrumental analyses were used to evaluate the texture quality of light (4.55%) (control group), low‐fat (2%) and fat‐free vanilla ice creams. The experimental mixes were significantly more viscous than the control mix due to the water binding capacity of carbohydrate‐ and protein‐based substances. The texture scores of the ice creams (sensory evaluation) paralleled the viscosity values. Ice creams manufactured with fat replacers were free of cooked‐milk flavor. The energy value of ice cream was reduced compared to full‐fat ice cream (207 kcal/100 g): by 75% for non‐fat ice cream, 71% for low‐fat ice cream and 41% for light ice cream. An increase in total solids in the mix resulted in better texture, a lower melting rate and better shape retention.  相似文献   
129.
Weathering and hydrothermal alteration of the granitic rocks in the Eastern Black Sea Region (NE Turkey) are important phenomena affecting the engineering projects in the region. The study investigated the probable paths of rock-forming mineral transformations due to weathering in the Harsit granitoid rocks, the changes of the major oxides as a consequence of weathering and the effects of weathering on the engineering properties. To identify the changes in the major oxides, the volume concentrations were considered in relation to the dry density. Chemical leaching during weathering was shown to be significant in changing the minerals. It was concluded that the engineering properties of the weathered granitic rocks can be most reliably predicted by P-wave velocity.   相似文献   
130.
The regeneration of declining waterfronts has been one of the crucial tasks of urban policy since the 1970s; whereas culture has become an important theme as means for responding to the socio-economic decline that waterfronts have been facing through the re-functioning of abandoned factories and warehouses, the rehabilitation of historic neighborhoods and the utilization of events and amenities. At the same time, many academics are critical on the attempts to reform post-industrial spaces of consumption in creating privatized spaces and commodified cultures excluding social milieu. Within this context, the research attempts to discuss the contribution of culture-led approaches in the regeneration of Istanbul waterfront by using a case study of the Golden Horn Cultural Valley Project (GHCVP) as empirical evidence. The GHCVP is not only one of the most important indicators of wider governmental emphasis on culture as a way of reviving Istanbul’s waterfront; but also it provides major discussions and claims on the impact of these developments, especially those regarding the historic environment, local community and economy. The results of this research respond to questions about what makes waterfront regeneration a success and what role the culture-led approaches should play in the process of waterfront regeneration.  相似文献   
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