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排序方式: 共有153条查询结果,搜索用时 31 毫秒
31.
采用十六烷基三甲基溴化铵(HDTMA)改性高岭土,研究制备条件对有机磷农药甲基异柳磷的吸附性能影响.结果表明,在室温(23~30 ℃)和pH 值为4的条件下,用30 μmol*g-1的HDTMA反应15 min,改性制备的有机高岭土对甲基异柳磷的吸附效果最佳.改性高岭土吸附能力比未改性高岭土明显增强,吸附等温线符合Freundlich等温吸附方程.吸附反应速度较快,在最佳吸附条件下,即有机高岭土投加质量浓度为10.0 g*L-1,溶液中甲基异柳磷初始质量浓度为30 mg*L-1,吸附平衡时间为40 min.在所选pH=5~9的范围内,有机改性高岭土对甲基异柳磷的吸附率均能保持在80%左右.  相似文献   
32.
In this study, natural Algerian kaolin was used as a support and impregnated with nickel at different loading amounts (2 wt.%, 5 wt.%, and 7 wt.%) in order to prepare a supported catalyst. The wet impregnation technique was used in this preparation; nickel oxide (NiO) was the active phase precursor of the catalyst, and the catalysts were designated as follows: 2%, 5%, and 7% Ni/kaolin. These catalysts were put to the test in catalytic wet peroxide oxidation (CWPO) for degrading the organic contaminant malachite green dye (MG). Analytical techniques such as FTIR spectroscopy, X-ray diffraction, BET, and X-fluorescence were used to examine the structure, morphology, and chemical composition of the support and the produced catalysts. Several parameters, including temperature, catalytic dose, metal loading, hydrogen peroxide volume, and kinetic model were systematically investigated. The combination of improved parameters resulted in a significant increase in the catalytic activity, achieving a high removal rate of MG dye of 98.87%.  相似文献   
33.
通过一种可变换阵列式电极的电动-可渗透反应墙(EK-PRB)装置,以沸石+粉煤灰组合为PRB材料,研究了电压梯度和土壤含水率在EK-PRB修复Pb(Ⅱ)污染土壤的过程中对于去除效果的影响。试验过程中,修复周期定为5 d,设置了不同的电压梯度(1.5,2.0,2.5 V/cm)和含水率(25%,30%,35%),进行了9组正交试验。结果表明,提高电压梯度、增大含水率对于Pb(Ⅱ)去除效果均具有增强作用,由此得出了以沸石+粉煤灰作为PRB材料时,EK-PRB修复Pb(Ⅱ)污染土壤的含水率和电压梯度最佳组合,即在电压梯度和含水率分别为2.5 V/cm和35%时,Pb(Ⅱ)的修复效果最好,去除率最高达到了80.7%。证明了沸石和粉煤灰作为组合材料时,EK-PRB联合修复技术在处理Pb(Ⅱ)污染高岭土时的可行性,可以为EK-PRB在PRB材料的改性和创新上的发展提供支持和依据。  相似文献   
34.
致色杂质降低了高岭土的亮度并限制了它的应用范围。该文研究了一种深色的沉积高岭土受诸致色因素的影响。采用常规的选矿方法不能有效地改善其色质状况,而将它转化为无定形二氧化硅产品是一种可行的利用途径。  相似文献   
35.
合成A型分子筛的矿物原料中石英的转化与活化   总被引:2,自引:0,他引:2  
赵经贵  霍丽华 《应用化学》1996,13(2):113-114
合成A型分子筛的矿物原料中石英的转化与活化赵经贵,张斌,刘景茂,张新,霍丽华,陈耐生(黑龙江大学化学系哈尔滨150080)(福州大学化学系福州)关键词 石英,高岭土,转化,活化,分子筛由高岭土、煤矸石合成A型分子筛[1~3],其中所含石英杂质影响分子...  相似文献   
36.
Summary In this paper the optimization of the kaolin calcination is studied, aiming at using the produced metakaolin as supplementary cementitious material. Representative samples of poor Greek kaolin (Milos island) and a high purity commercial kaolin were tested. Samples were heated at different temperatures during different times. The optimization of calcination conditions was studied by DTA-TG and XRD analysis of the raw and thermal treated kaolin samples, by pozzolanic activity analysis of metakaolins and finally by strength development analysis of cement-metakaolin mixtures. This approach showed that heating at 650°C for 3 h is efficient to convert poor kaolins with low alunite content to highly reactive metakaolins. However in the case of kaolin with a high alunite content, thermal treatment at 850°C for 3 h is required in order to remove undesirable SO3. Evidence was found that poor kaolins can be efficiently used for the production of highly reactive metakaolins.  相似文献   
37.
In Situ Synthesis of NaY Zeolite with Coal—Based Kaolin   总被引:3,自引:0,他引:3  
NaY zeolites were in-situ synthesized form coal-based kaolin via the hydrothermal method. The effects of various factors on the structure of the samples were extensively investigated.The samples were characterized by N2 adsorption,XRD,IR and DTG-DTA methods,and the results show that the crystallization temperature and amount of added water play an important role in the formation of the zeolite structure.The 4A and P zeolites are the competitive Phaes present in the resulting product.However,NaY zeolites wiht a higher relative crystallinity,excluding impure crystals and the well hydrothermal stapore size distribution,and this means that optimization of this process might result in a commercial route to synthesize NaY zeolites form coal-based kaolin.  相似文献   
38.
The potential to improve mechanical, structural, and mechanochemical properties of charge‐functionalized poly(N,N‐dimethylaminoethyl methacrylate) (PDMAEMA)‐based hybrid cryogels is investigated. The simple and versatile synthesis of hybrid cryogels with high strength and toughness using cationic DMAEMA and ionic comonomer 2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid has been proposed via in situ free‐radical crosslinking (cryo)polymerization by which the properties of virgin polymer can be modulated to required applications by incorporation of inorganic filler kaolin (KLN). Two factors affecting swelling and elasticity of hybrid gels (referred as PDA/KLNm), KLN content and gel preparation temperature, are studied. The optimum KLN concentration for desired swelling and modulus of elasticity is determined as 0.80% (w/v). Effective crosslinking density of hybrid hydrogels increases with KLN addition and this dependence is expressed by a quadratic polynomial as a function of KLN concentration. The results show that obtained hybrid gels with multiresponsive properties could be regarded as “smart materials” in sensing and actuation applications. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 1758–1778  相似文献   
39.
印染废水具有污染物浓度高、种类多、含有毒有害成分、COD含量高以及色度高等特点.实验采用无机絮凝剂硫酸亚铁制备改性高岭土,研究其改性过后对印染废水的处理效果.通过硫酸亚铁-高岭土相混合后的不同配比、不同投加量、pH值、反应温度和反应时间等因素来探究对印染废水的最佳处理效果.研究结果表明:稀释20倍后的印染废水的COD为64、pH为7.30.改性过后在配比为1∶7、投加量为2.5g、pH为6.92、反应温度为20℃、反应时间为20min的条件下,比较发现色度的去除率高达98.3%、COD的去除率高达68.75%,说明该方法对印染废水的处理效果较好.  相似文献   
40.
高岭土经煅烧、粉碎、表面改性处理后可制取橡胶补强填料.经改性处理对补强性能影响的实验研究表明:高岭土由于其本身性质的特殊性,极易在表面进行接枝改性;过320目筛;经含量为3%的处理剂表面改性后的高岭土填料对橡胶具有较好的补强作用,可完全替代碳酸钙或陶土,产生较好的补强效果,也可部分替代炭黑,降低生产成本.表6,参3  相似文献   
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