首页 | 官方网站   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   213篇
  免费   6篇
工业技术   219篇
  2023年   8篇
  2022年   7篇
  2021年   6篇
  2020年   7篇
  2019年   3篇
  2018年   9篇
  2017年   5篇
  2016年   10篇
  2015年   3篇
  2014年   12篇
  2013年   17篇
  2012年   7篇
  2011年   16篇
  2010年   5篇
  2009年   4篇
  2008年   9篇
  2007年   4篇
  2006年   5篇
  2005年   7篇
  2003年   2篇
  2002年   3篇
  2001年   2篇
  2000年   6篇
  1999年   4篇
  1997年   2篇
  1996年   6篇
  1995年   5篇
  1994年   3篇
  1993年   3篇
  1992年   2篇
  1991年   2篇
  1990年   2篇
  1989年   1篇
  1988年   1篇
  1987年   1篇
  1984年   4篇
  1983年   6篇
  1981年   1篇
  1980年   1篇
  1979年   1篇
  1978年   1篇
  1977年   2篇
  1976年   3篇
  1975年   1篇
  1974年   2篇
  1973年   1篇
  1972年   1篇
  1970年   1篇
  1968年   1篇
  1948年   1篇
排序方式: 共有219条查询结果,搜索用时 15 毫秒
131.
The effective utilisation of Moringa oleiferia mature leaves (MOL) extract as an antioxidant in cooked goat meat patties during refrigerated storage was investigated, and its efficiency was evaluated against butylated hydroxytoluene (BHT). The extract exhibited high phenolic content (48.36 mg of gallic acid equivalent per g), flavonoid (31.42 mg g?1 of sample) being the major component. Moringa oleiferia mature leaves extract showed excellent antioxidant activity as determined by radical‐scavenging activity of 1, 1‐diphenyl 2 picrylhydrazyl (DPPH). The IC50 value of MOL extract for 2, 2‐diphenyl‐1‐picrylhydrazyl radical scavenging was 18.54 μg mL?1. Total phenolic content (as gallic acid equivalent) significantly (P < 0.05) increased from 285.56 in control to 379.45 in patties with MOL extract. MOL extract (0.1%) when added to meat was found to retard lipid peroxidation of cooked goat meat patties as measured by TBARS number during refrigerated storage. The increase in TBARS number in MOL extract–treated samples was very slow and remained lowest (0.53 mg malonaldehyde per kg sample) up to 15 days. The antioxidant activity of MOL extract was found to be comparable to BHT. Addition of MOL extract did not affect any of the sensory attributes of patties. The MOL extract at a level of 100 mg/100 g meat was sufficient to protect goat meat patties against oxidative rancidity for periods longer than the most commonly used synthetic antioxidant like BHT.  相似文献   
132.
133.
134.
Various countries around the globe face numerous hazards due to the burning of coal on the surface as well as below ground. Countries like China, India, United States of America (USA), Australia, Indonesia, and many other countries have reported the burning of coal fires, and thus it is the urgent need to control the coal fire propagation to prevent the loss of energy resources. Coal is a fossil fuel that has a tendency to catch fire for many reasons; spontaneous combustion being the most frequent reasons for its burning. Other factors leading to coal fire include forest fires close to coal seams, natural hazards, old mining techniques, and external heat sources. The review work demonstrates the application of various satellite data in fire detection and mapping. The literature reveals that remote sensing plays an important role in facilitating quick and complete delineation of coal mine fires. Many algorithms have been developed around the world for fire detection from different satellite data. A comprehensive demonstration of different algorithms along with their merits and demerits are outlined. Comparative performances of the different algorithms with their case studies are also explained. It can be inferred from the various literature that it is very difficult to select a particular sensor algorithm for generating global fire products. Suggestions are given to further explore the possibility of improvement of fire detection algorithms.  相似文献   
135.
136.
An operation strategy known as two-tier “pressure consolidation” of delivered tube-trailers (or equivalent supply storage) has been developed to maximize the throughput at gaseous hydrogen refueling stations (HRSs) for fuel cell electric vehicles (FCEVs). The high capital costs of HRSs and the consequent high investment risk are deterring growth of the infrastructure needed to promote the deployment of FCEVs. Stations supplied by gaseous hydrogen will be necessary for FCEV deployment in both the near and long term. The two-tier pressure consolidation method enhances gaseous HRSs in the following ways: (1) reduces the capital cost compared with conventional stations, as well as those operating according to the original pressure consolidation approach described by Elgowainy et al. (2014) [1], (2) minimizes pressure cycling of HRS supply storage relative to the original pressure consolidation approach; and (3) increases use of the station's supply storage (or delivered tube-trailers) while maintaining higher state-of-charge vehicle fills.  相似文献   
137.
The cost of hydrogen delivery for transportation accounts for most of the current H2 selling price; delivery also requires substantial amounts of energy. We developed harmonized techno-economic and life-cycle emissions models of current and future H2 production and delivery pathways. Our techno-economic analysis of dispensed H2 costs guided our selection of pathways for the life-cycle analysis. In this paper, we present the results of market expansion scenarios using existing capabilities (for example, those that use H2 from steam methane reforming, chlor-alkali, and natural gas liquid cracker plants), as well as results for future electrolysis plants that use nuclear, solar, and hydroelectric power. Reductions in greenhouse gas emissions for fuel cell electric vehicles compared to conventional gasoline pathways vary from 40% reduction for fossil-derived H2 to 20-fold for clean H2. Supplemental tables with greenhouse gas emissions data for each step in the H2 pathways enable readers to evaluate additional scenarios.  相似文献   
138.
Cardio Vascular disease (CVD), involving the heart and blood vessels is one of the most leading causes of death throughout the world. There are several risk factors for causing heart diseases like sedentary lifestyle, unhealthy diet, obesity, diabetes, hypertension, smoking and consumption of alcohol, stress, hereditary factory etc. Predicting cardiovascular disease and improving and treating the risk factors at an early stage are of paramount importance to save the precious life of a human being. At present, the highly stressful life with bad lifestyle activities causes heart disease at a very young age. The main aim of this research is to predict the premature heart disease based on machine learning algorithms. This paper deals with a novel approach using the machine learning algorithm for predicting the cardiovascular disease at the premature stage itself. Support Vector Machine (SVM) is used for segregating the CVD patients based on their symptoms and medical observation. The experimentation results by using the proposed method will facilitate the medical practitioners to provide suitable treatment for the patients on time. A sophisticated model has been developed with the current approach to examine the various stages of CVD and the performance metrics used have given effective and fruitful results as compared to other machine learning techniques.  相似文献   
139.
Scientometrics - The article presents an introduction to a newly created scientometric portal called Indian Science Reports, available at www.indianscience.net . The portal is designed to fulfil...  相似文献   
140.
Pattern Analysis and Applications - The most important structural characteristics in the study of large-scale real-world complex networks in pattern analysis are degree distribution. Empirical...  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-23

京公网安备 11010802026262号