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231.
232.
通过浙江大学西溪校区东一教学楼改造的雨水收集工程实践,分析了本地的气象资料、回用水使用与降水时段调节等,将房间空调器凝结水与饮用水反渗透浓水予以收集归入整个雨水收集系统,用于教学楼周围的绿化浇灌与景观水的补水.通过计算,教学楼夏季空调器凝结水量约为3.48 m3/d,每日饮用水反渗透浓水的水量可达到198~396 L.在气温较高的夏季能有效地补充因大量蒸发导致绿化浇灌及景观补水不足的缺陷,同时在降雨量较少的冬季也能一定程度上进行添补.雨水与冷凝水以及反渗透浓水一同收集大大提高了整个收集系统的经济性.项目实测数据验证了系统的经济合理性. 相似文献
233.
相变蓄能技术是近年来材料领域新兴的研究热点,该技术对建筑节能、解决能源紧张有着重要的研究价值.文章将硅藻土和膨胀石墨作为吸附基体,吸附适合相变点的石蜡相变材料,制成三元复合相变蓄能材料掺入水泥砂浆中,并以火电厂炉渣代替黄砂作为砂浆中的细骨料,制成轻质高强蓄热地板,同地暖系统相结合,并利用太阳能或者工业废热等清洁能源对相变材料进行间歇式蓄热,以达到节能环保的功效.对制成的相变蓄能地板模型进行热工性能模拟的试验结果表明:相变蓄能地板具有良好的蓄热能力和经济环保效益,可以作为今后南方冬季取暖的一条有效途径,以缓解南方因采用集中供暖而造成能源紧缺的问题. 相似文献
234.
Guofeng Shen Rui Xiong Yanlin Tian Zhihan Luo Bahabaike Jiangtulu Wenjun Meng Wei Du Jing Meng Yuanchen Chen Bing Xue Bin Wang Yonghong Duan Jia Duo Fenggui Fan Lei Huang Tianzhen Ju Fenggui Liu Shunxin Li Xianli Liu Yungui Li Mu Wang Ying Nan Bo Pan Yanfang Pan Lizhi Wang Eddy Zeng Chao Zhan Yilin Chen Huizhong Shen Hefa Cheng Shu Tao 《国家科学评论(英文版)》2022,9(7)
The household energy mix has significant impacts on human health and climate, as it contributes greatly to many health- and climate-relevant air pollutants. Compared to the well-established urban energy statistical system, the rural household energy statistical system is incomplete and is often associated with high biases. Via a nationwide investigation, this study revealed high contributions to energy supply from coal and biomass fuels in the rural household energy sector, while electricity comprised ∼20%. Stacking (the use of multiple sources of energy) is significant, and the average number of energy types was 2.8 per household. Compared to 2012, the consumption of biomass and coals in 2017 decreased by 45% and 12%, respectively, while the gas consumption amount increased by 204%. Increased gas and decreased coal consumptions were mainly in cooking, while decreased biomass was in both cooking (41%) and heating (59%). The time-sharing fraction of electricity and gases (E&G) for daily cooking grew, reaching 69% in 2017, but for space heating, traditional solid fuels were still dominant, with the national average shared fraction of E&G being only 20%. The non-uniform spatial distribution and the non-linear increase in the fraction of E&G indicated challenges to achieving universal access to modern cooking energy by 2030, particularly in less-developed rural and mountainous areas. In some non-typical heating zones, the increased share of E&G for heating was significant and largely driven by income growth, but in typical heating zones, the time-sharing fraction was <5% and was not significantly increased, except in areas with policy intervention. The intervention policy not only led to dramatic increases in the clean energy fraction for heating but also accelerated the clean cooking transition. Higher income, higher education, younger age, less energy/stove stacking and smaller family size positively impacted the clean energy transition. 相似文献