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1.
With the cessation of milk quotas in the European Union, dairy herd sizes increased in some countries, including Ireland, with an associated increase in labor requirement. Second to feed costs, labor has been identified as one of the highest costs on pasture-based dairy farms. Compared with other European Union countries, Ireland has historically had low milk production per labor unit; thus, optimization of labor efficiency on farm should be addressed before or concurrently with herd expansion. The objective of this study was to quantify current levels of labor input and labor efficiency on commercial pasture-based dairy farms and to identify the facilities and management practices associated with increased labor efficiency. Thirty-eight dairy farms of varying herd sizes, previously identified as labor-efficient farms, were enrolled on the study and data were collected over 3 consecutive days each month over a 12-mo period, starting in May 2015 and finishing in August of 2016. This was achieved through the use of a smartphone application. For analysis purposes, farms were categorized into 1 of 3 herd size categories (HSC): farms with <150 cows (HSC 1), 150–249 cows (HSC 2), or ≥250 cows (HSC 3). Overall farm labor input increased with HSC with 3,015, 4,499, and 6,023 h worked on HSC 1, 2, and 3, respectively. A higher proportion of work was carried out by hired staff as herd size increased. Labor efficiency was measured as total hours input to the dairy enterprise divided by herd size. Labor efficiency improved as herd size increased above 250 cows with 17.3 h/cow per yr observed for HSC 3; labor efficiency was similar for HSC 1 and 2, at 23.8 and 23.3 h/cow per yr, respectively. A large range of efficiency was observed within HSC. The labor requirements had a distinct seasonal pattern across the 3 HSC with the highest input observed in springtime (February to April) primarily due to calving and calf-care duties, milking, and winter feeding. The lowest input was observed in wintertime (November to January) when cows were dry. Particular facilities and management practices were associated with efficiency within certain tasks, the most notable in regard to milking and winter feeding practices. Additionally, the most efficient farms used contractors to perform a higher proportion of machinery work on farm than the least efficient farms.  相似文献   
2.
Six olive oils extracted from the cultivars Arbequina, Arbosana, Coratina, Frantoio, Koroneiki, and Picual from 2017 and 2018 harvests, cultivated in Pinheiro Machado, Rio Grande do Sul, Brazil, are evaluated for standard oil composition parameters and bioactive constituents (pigments, tocopherols, and phenolic compounds). Multivariate principal component analysis (PCA) and univariate ANOVA and Fisher's LSD test are used to verify the effect of cultivar and harvest year on oil composition. Olive oil composition met extra virgin olive oil (EVOO) standard parameters and is influenced by both cultivar and harvest year. EVOO produced in 2018 has greater chlorophyll, caffeic acid, ligstroside aglycone, hydroxyoleuropein aglycone, syringic acid, and hydroxytyrosol acetate contents than the EVOOs from 2017. Linoleic acid, ferulic acid, ligstroside aglycone, and hydroxytyrosol acetate are the variables whose contents most contributed to the differentiation of oils by cultivar in both harvest years. Chemical characterization analyses allow for the differentiation of oil composition based on harvest year and cultivar. Metabolic quality data obtained here support the establishment of a local EVOO profile and the compounds that most contributed to treatment differentiation may serve as markers that can be utilized in determining origin, cultivar, and harvest year. Practical Applications: Olive production in Brazil is recent and is based on European cultivars which have not been bred for the local environmental conditions. Therefore, the measurement of olive oil metabolic quality will determine cultivar adaptability to local edaphoclimatic conditions as well as assist in the establishment of a standard of identity for the product and promote the development of its market. Olive oil produced in Southern Brazil shows high quality, and is especially rich in phenolic compounds. Although harvest year influences oil composition, oil from both harvests meet EVOO standards and cultivar specific metabolic markers are observed. This study provides the foundation for olive producers in Southern Brazil to seek authentication of the geographical origin of olive oil.  相似文献   
3.
基于大黑河流域6个气象站1966~2013年气温、降水量、蒸发皿蒸发量、相对湿度和日照时数长期数据系列,采用气候倾向率和滑动t检验法分析了近50年大黑河流域气象要素的变化趋势及变异年份。结果表明,大黑河流域整体呈现暖干气候倾向,气温呈显著增高趋势,变化率为0.43~0.57℃/10a,气温增温变点大致出现了两次,分别在1986、1997年;降水量和蒸发量多呈不显著减少趋势,降水量先减(1981年)后增(1990年),蒸发皿蒸发量先减(1986年)后增(1996年);相对湿度、日照时数多呈显著减小趋势。  相似文献   
4.
王守祯 《山西煤炭》2006,26(1):6-10
对2006年的煤炭工业工作,提出了思路和规划,制定了相应的措施。  相似文献   
5.
建筑能耗分析逐时气象资料的开发研究   总被引:16,自引:4,他引:16  
逐时气象资料对建筑能耗动态模拟是不可缺少的。在编制《夏热冬冷地区居住建筑节能设计标准》时 ,应用了动态模拟计算软件。为了开发逐时气象资料 ,通过与美国劳伦斯·伯克利国家实验室的技术合作 ,研究建立了我国城市的逐时资料。介绍了由我国气象台站报道的气象参数建立太阳辐射量的数学模型 ,阐述了典型气象月的选取原则 ,以及逐时数值插补方法。  相似文献   
6.
本文采用典型气象年法,以近30年(1989~2018年)逐时气象参数为计算依据,分析研究了宿州地区空气潮湿程度年分布特征与变化规律。以典型气象年自然通风工况下建筑围护结构内表面结露为判定特征指标,定义了结露温度基数。当室外逐日干球温度与露点温度的差值低于结露温度基数时,其差值倒数的累加值为潮湿强度值。研究表明宿州地区全年潮湿程度呈现季节性变化,夏季气候潮湿强度出现极大值达到15.31 d/℃,全年占比35%,潮湿程度出现最大38天。冬季出现极小值7.84 d/℃,全年占比18%,潮湿程度出现最小18天。各月中7月潮湿强度值最大,2月最小。全年潮湿强度值达到43.35 d/℃,潮湿程度出现98天。自然气象年中与前20年比较近10年潮湿强度均值下降16%,表明宿州地区气候有偏干燥的趋势。  相似文献   
7.
邱相武  师瑜莹 《山西建筑》2007,33(23):239-240
讨论了砖混结构、框架结构和框架剪力墙结构三种结构形式采用外保温体系在不同保温层厚度下对平均传热系数和全年能耗的影响,比较了这三种围护结构对建筑节能的影响,以达到降低建筑能耗、节约能源的目的。  相似文献   
8.
The paper presents an extended method for exergy analysis of buildings and Heating Ventilation Air Conditioning (HVAC) systems, according to an energy demand build-up model from the building side to the energy supply side. The HVAC systems comprise a thermal energy emission and control system, a thermal distribution system, an electricity distribution system and an energy conversion system. Energy and exergy that are required by a building and a HVAC system are posed into the external part and classified by different forms of energy carriers. The external part is out of the boundary of the study. The method is illustrated with an office building equipped with low-temperature heating and high-temperature cooling systems situated in the Netherlands. Thermal exergy and thermal energy demands of the building and thermal energy and thermal exergy losses occurring in the HVAC systems are discussed. The building and the HVAC systems to be considered meet standard Dutch energy performance regulations. Nevertheless their overall exergy efficiencies are low in both cases (17.15% and 6.81% subsequently). The exergy analysis also pinpoints that the thermal energy emission and control system and the energy conversion system are the main causes of the exergy inefficiencies in the heating and cooling cases, respectively.  相似文献   
9.
刘玉强 《建筑电气》2007,26(4):59-60
总结了建筑物易遭雷击的14种情况,以一个发生雷击事故的工程为例,提出在进行防雷设计时,首先要对建筑物所处的环境、地理、地质、气象条件和雷电活动规律进行认真调查,凡符合这14种情况之一的,至少应按第三类防雷建筑设防。  相似文献   
10.
何选德 《山西建筑》2007,33(11):148-149
简述了电气安装与土建施工协调配合的重要性,根据多年工程实践,就电气安装与土建施工中的配合问题进行了深入探讨,以促进建筑工程各项工程施工中不同专业工程的协调性,更好地保证建筑物的质量。  相似文献   
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