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351.
ABSTRACT

The traditional consumption of edible insects is common in one third of the world's population, mostly in Latin America, Africa and Asia. There are over one thousand identified species of insects eaten in some stage of their life cycle; and they play important roles in ensuring food security. The most common way to collect insects are from the wild, which is seasonal with limited availability and has an increasing demand resulting in a disruption to the ecosystem. There is a growing interest shown in rearing insects for commercial purposes, and an industrial scale production will be required to ensure steady supplies. Industrial production will need to take into account the living environment of insects, the nutritional composition of their feed and the overall efficiency of the production system. We provide a short overview on the consumption of and rearing insects in Africa, Asia and Europe. For Africa, a snapshot is given for Nigeria, Ghana, Central African Republic, Kenya and Uganda, while the following countries are reported for Asia: China, Japan, Lao People's Democratic Republic, Thailand and Vietnam. In addition, a list of insect species with the highest potential for food and feed in the European Union is provided with some reference to The Netherlands and Finland. The review concludes that there is need to better understand the rearing and farming procedures that will yield high quality edible insects in Africa, Asia and Europe.  相似文献   
352.
Fecundity was investigated in wild Tribolium castaneum (Herbst) from southeast Queensland, Australia. Although the fecundity of T. castaneum has been investigated in laboratory studies, the reproductive potential of wild females may be less than that of females reared and tested under favourable laboratory conditions. Adult T. castaneum were trapped using corrugated cardboard traps baited with whole wheat flour on four occasions during May-July 1997 in a grain-growing area of southeast Queensland. After each trapping period, fecundity of individual wild females was assessed on whole wheat flour at 30°C and 55% erh. In addition, F1 adults were pooled, a sample was taken and fecundity of individual females was assessed similarly. Almost 90% of the adults were trapped on four of the 10 grain storage sites, and these sites yielded females on all four trapping occasions. There was no systematic effect of trapping period on fecundity of wild females, and in three of these four sites there was no effect at all. There were no significant differences between numbers of progeny produced by F1 females derived from different trapping periods, so the data were pooled for comparison with the results from wild females. Generally, fecundity of wild females was high relative to that of F1 females which had been reared under uniformly favourable conditions in the laboratory. Despite the trapping occurring during some of the coldest months of the year, females were clearly active and capable of reproducing, demonstrating the importance of maintaining high levels of grain hygiene throughout the year.  相似文献   
353.
This study aims to bring together the types of cheese produced in the Southeastern Anatolia Region, which is rich in dairy products. Five different types of cheese were identified within this remit. These are: Urfa White Cheese, Antep Sιkma Cheese, Örgü (Eritme) Cheese, Otlu Cheese, and Künefe Cheese. Despite the relatively low number of types of cheese, the Region's cheese is renowned throughout Turkey. This publication covers the production, physical structure, and appearance of local cheeses, and the chemical and microbiological properties of some of the cheeses.  相似文献   
354.
Human body acquires a significant amount of vitamin D by cutaneous synthesis under the action of sunlight and less is supplied through nutritional sources. Diversified sociocultural and economic determinants have been identified that limit the dietary intake of vitamin D and enough distribution of sunlight to maintain optimal levels of 25-hydroxyvitamin D (25(OH)D). Consequently, the world has witnessed a high prevalence of hypovitaminosis D in resource-limited South Asian countries. The purpose of this review is to provide a South Asian perspective of vitamin D status, critically examining India, Pakistan, Bangladesh, and Sri Lanka, and to shed light on potential determinants (latitude and season, sunshine exposure habits, age, gender, and genetic factors) leading to hypovitaminosis D among a variety of population groups. Literature search was carried out using bibliographic databases “PubMed,” “Google Scholar,” and “ScienceDirect.com.” Serum 25(OH)D level, 20–50 nmol/L, was mainly taken as vitamin D deficiency, and determinants of low serum 25(OH)D concentration of the population under study were also considered. The review concludes that vitamin D deficiency is highly prevalent among South Asian populations and global efforts are needed to overcome hypovitaminosis in the region. In addition, dietary diversification, supplementation and fortification of foods with vitamin D, adequate exposure to sunlight, and consumption of animal foods were suggested as viable approaches to maintain 25(OH)D levels for optimal health.  相似文献   
355.
Water flow patterns in the Mekong are changing because of on‐going rapid hydropower development triggered by economic growth. Of immediate concern are the current and proposed hydropower dams in the transboundary Srepok, Sesan and Srekong (3S) Rivers, which contribute up to 20% of the Mekong's annual flows, have a large potential for energy production and provide critical ecosystem services to the downstream Tonle Sap Lake and Mekong Delta. The objective of this paper is to determine how the operation of the proposed largest individual dams and cascade dam schemes in the 3S Rivers will affect flow regimes and energy production. Daily flows were simulated over 20 years using the Soil and Water Assessment Tool and HEC‐ResSim models for a range of dam development and operations scenarios. The development of all dams in the 3S basin under an operation scheme to maximize individual electricity production results in an average 98% increase in dry season flows at the 3S outlet. Over 55% of dry season flows changes are caused by seven proposed large dams, with the Lower Srepok 3 project causing the highest impact. The seven large dams will generate 33.0 GWh/day with a water volume of 17 679 x 106 m3, compared with the current and definite future dams generating 73.2 GWh/day with a much lower volume of 6616 x 106 m3. When a cascade of dams are operational, downstream dams with small reservoirs will produce more energy. However, the marginal increase in energy production from the development of additional dams in the 3S basin will decline rapidly relative to the required water storage increase,. Strategic decision‐making on the future of each large proposed dam in the 3S basin needs to be considered by local governments after understanding cumulative operation effects and with further consideration to the potential impact on downstream ecosystem productivity and livelihoods. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
356.
北方型含油气域大致相当于翁文波当年建立的北方体系,此外还包括翁文波的太平洋系的北部。北方型含油气域又可分为亚洲、欧洲和北美3 个含油气域。3个含油气域中,各有一个面积较大的陆核,从东到西为阿纳巴尔、波罗的和加拿大。在陆核外围环绕着古生界带、中生界带和新生界带;这种环带形态主要呈半环形,并且各带之间重合不多,但在北美落基山西麓有较大面积的重合。在各含油气域的含油气盆地中,含油气岩层比较单一;盆地类型有内克拉通、前陆及褶皱带、活动大陆边缘、离散大陆边缘和内裂谷。在沉积速率分析曲线上,往往是古生代、中生代和新生代呈单峰状态。在油气田(藏)形成过程中,罕见油气再次运移现象,即罕见复式石油系统。  相似文献   
357.
中亚与中国西北盆地构造演化及含油气性   总被引:8,自引:4,他引:8  
中亚及中国西北地区中生代以来就一直处于欧亚大陆的南缘。侏罗纪以来两地区经历了相似的构造演化,即侏罗纪-老第三纪的伸展构造阶段和新第三纪-第四纪的挤压构造阶段。始新世以来由于受印度板块和古欧亚板块陆陆碰撞挤压并持续向北推移的影响,形成了现今中亚及中国西北地区的盆山构造格局。中亚及中国西北地区贫地油气资源丰富,成藏条件优越。各盆地受后期改造程度不同,前陆冲断带是这些盆地山前带共有的构造特征,盆地内部构造差异大,新构造对油气的储集具有重要影响。  相似文献   
358.
高军诗 《电信科学》2004,20(12):31-32
本文主要介绍亚太二号国际海底光缆系统的工程背景、网络结构、系统构成和实施方案,并揭示亚太二号对中国通信业的重要意义.  相似文献   
359.
通过对东南亚地区房间空调器能效标准及其发展趋势的分析,发现东南亚地区房间空调器的测试标准和能效标准正处于升级阶段。各国能效测试标准主要参考国际标准ISO 16358-1:2013,并且根据各自地域气候条件相应调整与修订能效标准。研究结果有利于我国房间空调器出口产品平台的开发和模块化设计,提高产品开发效率。  相似文献   
360.
施训鹏 《天然气工业》2017,37(4):143-149
由于和油价挂钩的天然气定价机制不能反映中国以及东亚地区其他国家天然气市场的基本面,包括中国在内的几个东亚地区的国家都在考虑建立自己的天然气基准价格。为此,分析了建立中国天然气基准价格应有的动力,厘清了交易枢纽的基本概念,并提出形成中国天然气基准价格的基本条件,即:①具备供买卖双方交易合同的交易所;②具备明确交割地的交易枢纽;③具有标准化的交易产品;④具备竞争性的市场环境包括足够数量的市场参与者。基于上述条件,分析了形成中国天然气基准价格的现状:①中国目前仅仅建立了功能不全的现货交易所,仍缺乏明确定义的交易枢纽,不具备形成天然气中国价格的必要条件;②多个重要骨干管网的交汇地,或者管输能力充足的主要市场,都有望在未来成为基准枢纽。最后针对形成中国天然气基准价格提出建议:天然气市场化改革形成竞争性的天然气市场是形成基准价格的前提,在当前改革仍旧不到位的环境下,有关部门可以从理顺现货和期货交易平台的关系、建立交易枢纽着手,先夯实基础。  相似文献   
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