全文获取类型
收费全文 | 720篇 |
免费 | 164篇 |
国内免费 | 20篇 |
专业分类
电工技术 | 5篇 |
综合类 | 54篇 |
化学工业 | 311篇 |
金属工艺 | 8篇 |
机械仪表 | 1篇 |
建筑科学 | 141篇 |
矿业工程 | 66篇 |
能源动力 | 20篇 |
轻工业 | 25篇 |
水利工程 | 72篇 |
石油天然气 | 20篇 |
武器工业 | 1篇 |
无线电 | 17篇 |
一般工业技术 | 80篇 |
冶金工业 | 52篇 |
原子能技术 | 14篇 |
自动化技术 | 17篇 |
出版年
2024年 | 9篇 |
2023年 | 45篇 |
2022年 | 42篇 |
2021年 | 55篇 |
2020年 | 52篇 |
2019年 | 40篇 |
2018年 | 31篇 |
2017年 | 29篇 |
2016年 | 35篇 |
2015年 | 30篇 |
2014年 | 46篇 |
2013年 | 37篇 |
2012年 | 52篇 |
2011年 | 50篇 |
2010年 | 36篇 |
2009年 | 53篇 |
2008年 | 28篇 |
2007年 | 55篇 |
2006年 | 36篇 |
2005年 | 28篇 |
2004年 | 21篇 |
2003年 | 23篇 |
2002年 | 10篇 |
2001年 | 14篇 |
2000年 | 7篇 |
1999年 | 10篇 |
1998年 | 5篇 |
1997年 | 5篇 |
1996年 | 2篇 |
1995年 | 7篇 |
1994年 | 4篇 |
1992年 | 3篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1980年 | 1篇 |
排序方式: 共有904条查询结果,搜索用时 15 毫秒
81.
Kene Onwubuya Markus Puschenreiter Brian Bone Phillip Teasdale Pavel Tlustos Steve Waite Bernd Marschner 《The Science of the total environment》2009,407(24):6132-6142
A range of tools have been proposed to support decision making in contaminated land remediation. From a European perspective it is clear, however, that there are considerable national differences in the decision support process, and more generally in the extent to which this process supports the selection of less invasive, alternative remediation options such as phytoremediation, in situ immobilisation etc. (referred to here as “gentle” remediation technologies). In this paper we present results from the recently completed European Union ERANET SNOWMAN project SUMATECS (Sustainable Management of Trace Element Contaminated Sites), and critically review available decision support tools in terms of their fitness for purpose for the application of gentle remediation technologies. Stakeholder feedback indicates a lack of knowledge amongst stakeholders of currently available decision support tools. We propose that decision support which focuses on gentle remediation is more strongly incorporated into existing, well-established (national) decision support tools / decision-frameworks, to promote more widespread use and uptake. 相似文献
82.
83.
84.
85.
微生物修复技术是通过高耐受且人工驯化微生物的代谢作用将污染场地中的有害污染物降解的修复技术。提高微生物降解效率、探究代谢途径与中间代谢产物是含能材料污染场地的微生物修复的关键,为此,研究简述了含能材料的污染现状,介绍了修复含能材料污染场地的常见方法,探讨了微生物修复含能材料污染场地的优势,总结了微生物修复含能材料污染场地的常见菌株、外部营养源和实际应用,同时梳理了各含能材料在微生物降解过程中产生的中间代谢产物,归纳了典型含能材料降解过程中的代谢途径,最后展望了微生物在修复含能材料污染场地的发展方向:研究具有优良生物刺激效果的生物制剂,分析降解含能材料微生物菌株的宏基因组学、宏转录组学、宏蛋白质组学和宏代谢组学,加强DNA、RNA、蛋白质和代谢物等方面的研究,通过转基因技术来提升微生物对含能材料的降解效果,以更好地激发微生物修复含能材料污染场地的潜力。 相似文献
86.
Juliana Milheiro Luís Filipe-Ribeiro Alice Vilela Fernanda Cosme 《Critical reviews in food science and nutrition》2019,59(9):1367-1391
The presence of 4-ethylphenol, 4-ethylguaiacol and 4-ethylcatechol in red wines affect negatively their aroma conferring horsy, barnyard, smoky and medicinal aromatic notes. These volatile phenols formed from free hydroxycinnamic acids and their ethyl esters by Dekkera/Brettanomyces yeasts, can contaminate wines. Their formation can cause serious negative economic impact to the wine industry worldwide as consumers tend to reject these wines. For these reasons various preventive and remedial treatments have been studied. This review summarises the wine microbial volatile phenols formation, preventive measures during winemaking and remedial treatments in finished wines along with their advantages and limitations for dealing with this sensory defect and impact on wine quality. Also it is important to control the levels of volatile phenols in wines using fast and convenient analytical methods namely with a detection limit below their olfactory perception threshold. The analytical methods available for quality control and performance characteristics as well their advantages and disadvantages when dealing with a complex matrix like wine are discussed in detail. 相似文献
87.
随着工业的发展,特别是采矿冶炼等行业的发展,使含重金属的废弃物进入土壤,造成土壤重金属污染,对环境和人体健康产生极大威胁。本文以湖南怀化某铅锌矿渣堆放地周围污染土壤为研究目标,通过壳聚糖及其衍生物对污染土壤中重金属离子的稳定化实验,筛选出对目标重金属(Cd2+、Pb2+、Zn2+)具有最佳稳定效果的稳定剂,探究了稳定剂对土壤中重金属离子的稳定机理,并在模拟酸雨淋溶条件下研究了最佳稳定剂对重金属离子的长期稳定化效果。稳定化实验结果表明,壳聚糖及其衍生物对土壤重金属离子均有稳定化作用,其中羧甲基壳聚糖的稳定效果最好,其使污染土壤中重金属离子的可迁移性及生物有效性明显降低。通过重金属形态分析、扫描电镜(SEM)及X射线衍射(XRD)分析得出稳定剂与土壤中重金属离子发生反应生成络合物,并通过机理分析进一步验证了羧甲基壳聚糖的稳定效果最好;淋溶实验表明,羧甲基壳聚糖对土壤中重金属离子具有长期稳定性,经其稳定后土壤中重金属离子以更稳定不易迁移的形态存在,且使土壤环境得到改善,增强了土壤本身对重金属离子的稳定。羧甲基壳聚糖有望成为修复重金属(Cd2+、Pb2+、Zn2+)污染土壤的优良稳定剂。 相似文献
88.
Amanda Broska da Cruz Deniz Renata Bachmann Guimarães Valt Maria José Jerônimo de Santana Ponte Haroldo de Araújo Ponte 《化学工程与技术》2020,43(7):1393-1401
Transport phenomena are investigated which are involved in the electrokinetic remediation process used for removing vanadium from deactivated catalysts from oil catalytic cracking that are currently allotted to cement plants and class-I landfills. Variables such as the concentration of electrolyte, electric potential, and applied electric current were evaluated in order to determine the effects produced by electroosmosis, diffusion, hydraulic gradient, and electromigration on the removal of vanadium from the catalyst. It was observed that migration is the most relevant phenomenon in the remediation tests, and for the best remediation condition, the migratory flow accounted for about 87 % of the vanadium removal. 相似文献
89.
以国内某焦化企业场地多环芳烃污染土壤为研究对象,研究了过硫酸钠作为氧化剂时,硫酸亚铁或次氯酸钠助剂的使用对修复效率的影响,同时通过对比阐述了硫酸亚铁及次氯酸钠在过硫酸钠氧化体系中的不同作用。结果表明:微量硫酸亚铁对过硫酸钠氧化土壤中多环芳烃起到催化作用,可显著提高多环芳烃去除效率;次氯酸钠可与过硫酸钠协同使用,达到共氧化的目的。 相似文献
90.
Ufana Riaz S.M. Ashraf Jyoti Kashyap 《Polymer-Plastics Technology and Engineering》2015,54(17):1850-1870
Research in the field of TiO2-based photocatalysis has gained wide attention to address important energy and environmental problem. Lately, the use of conducting polymers as photosensitizers has proven to immensely enhance photodegradation by exhibiting excellent photocatalytic activity under both ultraviolet light and natural sunlight irradiation which is not possible using semiconductors alone. Considering the unique performance of conducting polymer-based nanocomposites in photocatalysis, the present review provides the recent advances in the development of ultraviolet and visible light-responsive conducting polymer-based TiO2 nanocomposites for their potential application in environmental remediation. This review ends with a summary focusing on the challenges and new dimensions in this still emerging area of research. 相似文献