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141.
John Gallagher Biswajit Basu Maria Browne Alan Kenna Sarah McCormack Francesco Pilla David Styles 《Journal of Industrial Ecology》2019,23(1):133-140
Renewable energy (RE) technologies are looked upon favorably to provide for future energy demands and reduce greenhouse gas (GHG) emissions. However, the installation of these technologies requires large quantities of finite material resources. We apply life cycle assessment to 100 years of electricity generation from three stand‐alone RE technologies—solar photovoltaics, run‐of‐river hydro, and wind—to evaluate environmental burden profiles against baseline electricity generation from fossil fuels. We then devised scenarios to incorporate circular economy (CE) improvements targeting hotspots in systems’ life cycle, specifically (1) improved recycling rates for raw materials and (ii) the application of eco‐design. Hydro presented the lowest environmental burdens per kilowatt‐hour of electricity generation compared with other RE technologies, owing to its higher efficiency and longer life spans for main components. Distinct results were observed in the environmental performance of each system based on the consideration of improved recycling rates and eco‐design. CE measures produced similar modest savings in already low GHG emissions burdens for each technology, while eco‐design specifically had the potential to provide significant savings in abiotic resource depletion. Further research to explore the full potential of CE measures for RE technologies will curtail the resource intensity of RE technologies required to mitigate climate change. 相似文献
142.
Summary Creeping bentgrass is a very important turfgrass species used extensively on golf course greens, fairways, and tees. One of
the challenges of creeping bentgrass management is the control of grassy weeds, most of which respond to herbicides in a similar
manner to that of creeping bentgrass. As part of a weed management program for golf courses, Roundup?-tolerant creeping bentgrass will be simple to employ and more effective in controlling problem weeds than currently available
methods. The goal of this research was to evaluate fitness-related reproductive traits in four transgenic creeping bentgrass
events modified to express a Roundup?-tolerant gene, cp4 epsps, to determine if these creeping bentgrass events had gained an unexpected reproductive fitness advantage. We compared transgenic
events ASR 333, ASR801 with their nontransformed tissue culture line, C99056L and transgenic events ASR365, ASR368 with their
non-transformed tissue culture line, B99061R. Populations of plants from three conventional cultivars were also included for
comparison to determine whether significant variations, if present in transgenic events, were novel to the non-transformed
organism, Agrostis stolonifera L. Our results showed that none of the four transgenic events surveyed were significantly different from the respective non-transformed
tissue culture line plants for the following characteristics: first heading date, anthesis duration, inflorescence length,
number of florets per inflorescence, pollen size, and seed-set capacity through open-pollination. One of the transgenic events,
ASR333, needed significantly more days for anthesis initiation than the nontransformed tissue culture line, C99056L; while
another transgenic event, ASR801, exhibited significantly shorter pollen longevity than plants of the tissue culture line,
C99056L. However, ASR801 was not significantly different from the conventional cultivars ‘Penn A-4’ and ‘Penncross’ for pollen
longevity. Plants of both transgenic events ASR365 and ASR368 did not differ significantly from plants of the tissue culture
line, B99061R, for all characters measured. 相似文献
143.
不同氮磷钾施肥方式对水稻碳、氮累积与分配的影响 总被引:6,自引:0,他引:6
基于我国南方双季稻区20年长期田间定位施肥试验,研究了不同氮磷钾施肥方式对水稻碳、氮积累与分配的影响.结果表明:偏施氮肥处理水稻籽实的碳、氮含量最高,分别达到433和18.9 g·kg-1.水稻植株的碳、氮储量以氮磷钾平衡施肥(NPK)及氮磷钾基础上有机物料循环施肥处理(NPKC)最高,其中NPKC和NPK处理籽实碳储量分别为2015和1960kg hm-2,茎叶碳储量分别为2048和2002 kg·hm-2;籽实氮储量分别为80.6和80.5kg·hm-2,茎叶氮储量则以NPK处理最高,为59.3 kg·hm-2.有机无机肥的配合施用显著增加了水稻植株体内碳和氮的累积;与偏施氮肥处理相比,氮磷钾的综合施用更利于水稻生长过程中碳、氮的累积与分配. 相似文献
144.
Yuichi Moriguchi Atsushi Terazono 《The International Journal of Life Cycle Assessment》2000,5(5):281-286
We developed a simplified emission dispersion and exposure-assessment model designed to reflect the site-specific health impacts
of air pollution in life-cycle impact assessment (LCIA). We proposed an EXposure Per Emission Coefficient (EXPEC), a dimensionless
parameter representing the relative amount of pollutant inhaled per emission. EXPEC values were calculated for two typical
source categories - electric power plants and road vehicles — on a concentric circle model. The EXPEC values were significantly
different for different locations and source categories. We examined the application of EXPEC in a case study that compared
the effects of emissions from electric and gasoline-engine vehicles. EXPEC is a useful tool for assessing spatially differentiated
potential impacts. 相似文献
145.
146.
147.
辽宁省辽河水生态系统健康评价 总被引:20,自引:1,他引:20
2009年6-8月,在对辽宁省辽河铁岭段、沈阳段、盘锦段20个断面水文、水质、着生藻类、栖息地状况实地调查的基础上,采用主成分分析方法,进行指标的筛选与指标权重的确定,构建了该河流水生态系统健康评价指标体系和健康评价标准体系,并用改进的灰色关联度法对辽河6个断面的水生态系统健康状况进行了评价.结果表明:辽宁省辽河3个评价断面的水生态系统健康程度一般,2个评价断面分别为较差和极差,仅有1个评价断面达到了亚健康程度,说明辽河河流水生态系统生态退化严重,需要进一步加强辽河水系的生态恢复及水环境污染综合治理. 相似文献
148.
维生素C为6碳多羟化合物,在化学反应中易失去电子,依次生成半脱氧抗坏血酸和脱氧抗坏血酸。因此,维生素C可作为自由基清除剂,能迅速与超氧阴离子、氢化氧基、过氧化氢、羟自由基反应,生成抗坏血酸自由基。蓝光作为一种短波长,靠近紫外线频段的光,具有能量高的特点,是自然界中导致视网膜色素上皮细胞损伤甚至凋亡的主要光线。本实验通过观察蓝光照射视网膜色素上皮,对其DNA的损伤产生光损伤作用,并比较加入维生素C后对这种光损伤的保护作用,以期探讨维生素C在 相似文献
149.
150.
植物螯合肽及其在抗重金属胁迫中的作用 总被引:11,自引:0,他引:11
植物螯合肽(PCs)广泛存在于植物体中,与植物抗重金属胁迫关系密切。植物螯合肽及其复合物是一类富含半胱氨酸的低分子量化合物。现有研究证明,PCS由谷胱甘肽(GSH)为底物的酶促反应合成,其合成受相关基因的调控,从模式植物拟南芥的突变体中已分离到与PCS合成有关的几个基因。植物螯合肽首先与重金属离子结合形成低分子量(LMW)复合物,以此形态经由细胞质进入液泡后,再与一个分子的植物螯合肽结合,形成对植物组织毒性较小的高分子量(HMW)复合物,从而达到缓解重金属对植物的危害作用。就植物螯合肽及其复合物的结构、生物合成、基因调控及重金属解毒机理等进行了综述,并对今后的研究方向提出了一些看法。 相似文献