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101.
有关生物堆肥化问题的探讨 总被引:1,自引:0,他引:1
介绍了生物堆肥化的基本概念、意义与作用。从堆肥化原理、堆肥化的影响因素及其控制、堆肥化工艺等方面对生物堆肥化进行了系统的阐述。 相似文献
102.
Yang Li Bin Chen Xiujun Wang Lei Zhai Ming Duan 《Journal of Dispersion Science and Technology》2018,39(8):1134-1139
An acrylic emulsion-type inverse demulsifier (named as PMEMA latex) was prepared by using methyl methacrylate (MMA), ethyl acrylate (EA), methacrylic acid (MAA), and acrylamide (AM) as monomers. The effects of reaction conditions toward the copolymerization results were investigated by evaluating various evaluation parameters, including conversion, molecular weight, and diameter. In addition, the interfacial properties of PMEMA latex were investigated to study its demulsification mechanism about treating the O/W emulsion. 相似文献
103.
对性质不同的大庆、孤岛原油进行了破乳剂评选。在此基础上合成出一批破乳剂,研究了破乳剂的组成对原油脱盐的影响规律。结果表明:两种原油所需破乳剂的HLB值有明显差别。提高破乳剂的分子量,可增强对两种原油的脱盐效果。 相似文献
104.
袁吉有 《云南大学学报(自然科学版)》2023,45(1):199-210
大气氮沉降是影响森林生态系统的新生态因子之一,过量氮沉降将改变参与森林生态系统物质转化和养分循环的土壤微生物.作者综述了国内外模拟氮沉降对森林土壤微生物生物量、群落结构和多样性、微生物活性和酶活性、底物利用能力以及功能基因的影响研究现状.结果表明:(1)整体来看,氮沉降对森林土壤微生物生物量产生负面影响的报道较多;(2)氮沉降改变了森林土壤微生物群落的构成和丰富性;(3)氮沉降短期内促进森林土壤呼吸速率,长期氮输入会抑制土壤呼吸速率;(4)氮沉降改变了参与凋落物分解相关土壤酶的活性;(5)氮沉降降低了土壤微生物代谢复杂有机质的代谢能力;(6)氮沉降增加和降低了某些微生物功能基因的丰度.此外,作者还探讨了氮沉降对森林土壤微生物研究存在的问题和未来研究的重点. 相似文献
105.
微生物传感器快速测定生化需氧量 总被引:1,自引:0,他引:1
利用微生物传感器快速测定水中生化需氧量。用该法对标准样品进行测定,测定结果的相对标准偏差为3.30%~4.67%(n=4),与标准值的相对误差在±5%之内。用该方法和经典稀释接种法对实际样品进行测定,该方法测定结果的相对误差为4.1%~11.3%。微生物传感器法能满足环境监测的要求。 相似文献
106.
Functionalized carbon black nanoparticles used for separation of emulsified oil from oily wastewater
Huanjiang Wang Haiyan Xu Weihong Jia 《Journal of Dispersion Science and Technology》2018,39(4):497-506
Functionalized carbon black (F-CB) nanoparticles were synthesized by covalently grafting the polyvinyl alcohol on carbon black (CB) surfaces and used as demulsifier to separate the oil from the emulsified oily wastewater. The bottle test showed that the residual oil content in the separated water was as low as ~50?mg/L corresponding to a demulsification efficiency of about 99.90% at an optimal condition within a few minutes. It was believed that the surface wettability of the carbon black could be tuned by modifying with the PVA molecules, which enables the F-CB nanoparticles to be readily migrated to the oil/water interface and have the opportunity to interact with and/or displace the stabilizers of the emulsion. As a result, the demulsification process was accomplished with the coalescence of the oil droplets promoted by the F-CB nanoparticles. The interaction behavior between F-CB nanoparticles and asphaltenes was investigated by quantum chemical calculations. The results showed that the F-CB nanoparticles have strong interaction with the asphaltene molecules in form of π?π and θ?π forces. The findings in present study are significant for understanding the demulsification mechanism and also provide a novel demulsifier for the demulsification of emulsified oily wastewater. 相似文献
107.
滚环扩增(RCA)技术是一种简单的恒温DNA扩增技术,在DNA聚合酶的催化下通过扩增闭合环状模板产生成千上万的重复序列。相较于变温核酸扩增技术如聚合酶链式反应(PCR),RCA无需昂贵的变温仪器,更适合现场检测。该文介绍了RCA技术的原理和分类,综述了其在细菌、病毒以及其它病原微生物检测方面的应用现状,并展望了RCA检测病原微生物的应用前景。RCA在检测病原微生物领域有着巨大潜力,同时可为新型冠状病毒(SARS-CoV-2)的快速检测提供思路和补充。 相似文献
108.
Prof. Lixin Xia Hairan Zhang Zhichao Wei Dr. Yi Jiang Prof. Ling Zhang Dr. Jie Zhao Junhui Zhang Li Dong Erni Li Prof. Laurent Ruhlmann Prof. Qian Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2017,23(8):1920-1929
Catalytic Janus nanosheets were synthesized by using an anion-exchange reaction between heteropolyacids (HPAs) and the modified ionic-liquid (IL) moieties of Janus nanosheets. Their morphology and surface properties were characterized by using SEM, energy-dispersive spectroscopy (EDS), FTIR spectroscopy, and X-ray photoelectron spectroscopy (XPS) studies. Because of their inherent Janus structure, the nanosheets exhibited good amphipathic character with ILs and oil to form a stable ILs-in-oil emulsion. Therefore, these Janus nanosheets can be used as both emulsifiers and catalysts to perform emulsive desulfurization. During this process, sulfur-containing compounds at the interface could be easily oxidized and efficiently removed from a model oil. Application of this Janus emulsion brings an efficient, useful, and green procedure to the desulfurization process. Compared with the desulfurization catalyzed by using HPAs in a conventional two-phase system, the sulfur removal of dibenzothiophene (DBT) achieved in a Janus emulsion system was improved from 68 to 97 % within 1.5 h. Moreover, this emulsion system could be demulsified easily by simple centrifugation to recover both the nanosheets and the ILs. Owing to the good structural stability of the Janus nanosheets, the sulfur removal efficiency of DBT could still reach 99.9 % after the catalytic nanosheets had been recycled at least six times. 相似文献
109.
通过对泸型酒发酵过程中主要做生物在不同发酵条件下代谢规律的研究,分析了自然状态下,泥窖这一特殊发酵容器内微生物代谢的特性,从而揭示了泸型酒窖内微生物发酵特征,指出了不同状态下的配料调整和技术措施。 相似文献
110.