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81.
In this paper, we have illustrated the utilisation of a second-sphere coordination approach to construct supramolecular inclusion solids with varieties of guest molecules. A flexible molecule N,N,N′,N′-tetra-p-methylbenzyl-ethylenediamine (L1) bearing doubly protonated H-bond donors was designed, capable of forming N–H…Cl hydrogen bonds with a crystallographically unique chloride anion, to construct an anion-directed ligand. The pillared double-layered host framework was constructed by an anion-directed ligand and primary coordination sphere [CoCl4]2 ? through weak C–H…Cl hydrogen-bonding interactions. A variety of guest molecules, such as p-anisaldehyde, 1,4-dimethoxy-2,5-bis(methoxymethyl)benzene, can be included, leading to the formation of novel supramolecular inclusion solids: [L1]·4[H]+·[CoCl4]2 ? ·2Cl? ·1.5[C8H8O2]·0.25[CH3OH] (1) and [L1]·4[H]+·[CoCl4]2 ? ·2Cl? ·1.5[C12H20O4]·0.5[CH3OH] (2). We have presented herein the utilisation of a second-sphere coordination approach to construct supramolecular inclusion solids with a variety of guest molecules. A novel type of a pillared double-layered host framework was constructed by a second-sphere coordination between the anion-directed ligand (L1 = N,N,N′,N′-tetra-p-methylbenzyl-ethylenediamine) and [CoCl4]2 ? through weak C–H…Cl hydrogen-bonding interaction, and a variety of guest molecules, such as p-anisaldehyde, 1,4-dimethoxy-2,5-bis(methoxymethyl)benzene, can be included, leading to the formation of supramolecular inclusion solids: [L1]·4[H]+·[CoCl4]2 ? ·2Cl? ·1.5[C8H8O2]·0.25[CH3OH] (1) and [L1]·4[H]+·[CoCl4]2 ? ·2Cl? ·1.5[C12H20O4]·0.5[CH3OH] (2) 相似文献
82.
Imre Dékány Anna Szücs KÁRoly Mogyorósi ZoltáN Király 《Molecular Crystals and Liquid Crystals》2013,570(2):363-368
Abstract Alkylammonium intercalated graphite oxides (R-GO), palladium intercalated alumina-pillared montmorillonites (Pd/Al2O3-PILC) and titania-pillared montmorillonites (TiO2-PILC) have been prepared and the intercalation materials have been characterized by BET surface area analysis, UV/VIS spectroscopy, ICP-AES, DTG-DTA, XRD and TEM measurements. R-GO particles were prepared by oxidation of natural graphite followed by organophilization with cationic surfactants. For TiO2-PILC and Pd/Al2O3-PILC the synthesis included the interlamellar adsorption of precursor species (polyaluminium-hydroxide, Pd-acetate and tetraethyl orthotitanate) from dilute solutions and subsequent chemical reactions at the montmorillonite/solution interface. 相似文献
83.
84.
氨水介质和氟处理对铝柱层柱粘土性质的影响 总被引:2,自引:0,他引:2
分别在氨介质和钠介质中制备了层柱蒙脱土和层柱累托石,并用氟化铵、氟硅酸铵和氟铝酸铵对层柱粘土进行处理,考察了处理条件对层柱粘土结构和酸性的影响. NH3-TPD和IR分析结果表明,氨介质中制备的层柱粘土比钠介质中制备的具有更强的酸性,经氟处理后层柱粘土的酸性有较大的提高. 氨介质中制备的层柱粘土的低钠含量是其酸性改善的主要原因,而氟处理对层柱粘土酸性的提高主要来自氟对铝柱的表面作用. 氟处理层柱粘土对异丙苯裂解具有很高的催化活性. 相似文献
85.
载体酸性对铜基交联黏土催化剂上C3H6选择性催化还原NO反应的影响 总被引:2,自引:0,他引:2
采用聚合羟基复合阳离子合成交联蒙脱土Al-Ce-PILC, 并分别用NH4NO3和(NH4)2SO4处理后, 将其作为载体, 采用浸渍法制备了应用于C3H6选择性催化还原NO反应的铜基交联黏土催化剂Cu/Al-Ce-PILC. 用Py-IR, IR和DSC等表征技术研究了不同处理方式对Al-Ce-PILC的结构、 酸性和催化剂活性的影响. 结果表明, 未经处理的Al-Ce-PILC中同时存在L酸和B酸, 以L酸为主, Cu/Al-Ce-PILC上NO的最大转化率仅为18。5%; 用NH4NO3处理提高了L酸量, NO转化率降低; 而用(NH4)2SO4处理改变了Al-Ce-PILC的酸性结构, 增大了B酸量, 并形成了超强酸中心, 催化剂上NO转化率显著提高, 在350 ℃时达最大值50.2%. B酸对于Cu/Al-Ce-PILC上NO的还原是必要的, 它有利于C3H6吸附并适度氧化为活性中间物种, 其酸量和酸强度的增加是催化剂活性改善的主要原因. 相似文献
86.
以铝柱撑蒙脱石为载体,用沉积沉淀法在其表面负载金属Au后制备了Au负载铝柱撑蒙脱石高效负载型催化剂。以XRD,TEM,XPS等手段对催化剂的结构进行了表征,并研究了铝柱撑蒙脱石负载前后CO催化氧化活性的变化规律。结果证明,Au是以高度分散的状态均匀分布在铝柱撑蒙脱石载体表面,且以Au0和Au3+的混合价态形式存在。CO催化氧化活性表征结果表明,负载后催化剂的催化活性有了显著提高,且其催化活性随着负载量的增加而不断增强,但当负载量增大到一定程度后,其催化活性不再继续增加,且有所下降。 相似文献
87.
Benito I. Blanco C. Martínez M. del Riego A. González F. Pesquera C. 《Journal of Thermal Analysis and Calorimetry》1999,55(2):461-466
Thermogravimetric analysis of pyridine adsorption was applied to study the acidity at different temperatures of clays pillared
with Al pillars and mixed Al-Ga pillars, in relation to the starting montmorillonite. These results were compared with those
obtained by means of a pulse-chromatographic technique. The pillaring process produces a large number of acid centers in the
samples. Al-Ga-PILC has a higher acidity than Al-PILC.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
88.
M?ssbauer Spectroscopy Study of Alumina-Supported Iron-Containing Catalysts for Hydrogen Sulfide Oxidation 总被引:1,自引:0,他引:1
N.S. Sakaeva V.A. Varnek G.A. Bukhtiyarova V.F. Anufrienko E.A. Sobolev B.P. Zolotovskii 《Reaction Kinetics and Catalysis Letters》2000,70(1):169-176
The pillared clay catalyst, which was obtained by exposing activated clay powder to sulfuric acid and aluminium salts and calcining in air at 373 – 673 K, was found to be highly active for the title reaction. The activity is mainly attributed to the Lewis acid sites and also to a small number of Brönsted acid sites, whose number and strength increases with the extent of pillaring. The kinetic equation of surface esterification is y = 2.57x - 1.47. 相似文献
89.
铁钛双金属共柱撑膨润土光催化-Fenton降解苯酚 总被引:6,自引:0,他引:6
通过简单的离子交换方法成功合成了铁钛双金属共柱撑膨润土催化剂, 并利用 N2 吸附、X 射线衍射和等离子体发射光谱对所合成的样品进行了表征. 以苯酚为目标污染物, 考察了 pH 值、催化剂的投加量以及双氧水的加入量等对苯酚降解性能的影响. 结果表明, 在中性条件和紫外光照射下, 铁钛双金属柱撑膨润土上苯酚降解率和矿化率都高达 95%, 且铁离子的溶出率始终低于 2 mg/L, 均优于单一铁柱撑膨润土催化剂. 经过五次循环测试, 催化剂均表现出较高的活性. 即使在碱性 (pH = 9.0) 条件下, 反应 180 min 苯酚降解率也高达 70.3%, 表现出较好的酸碱适应性. 并讨论了双金属柱撑土所具有较大的比表面积和较强的表面酸性与活性之间的关系. 相似文献
90.
Evidence of Amine–CO2 Interactions in Two Pillared‐Layer MOFs Probed by X‐ray Crystallography
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Xiao‐Li Hu Qi‐Han Gong Rong‐Lin Zhong Prof. Xin‐Long Wang Prof. Chao Qin Hao Wang Prof. Jing Li Kui‐Zhan Shao Prof. Zhong‐Min Su 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(19):7238-7244
Two pillared‐layer metal–organic frameworks (MOFs; PMOF‐55 and NH2‐PMOF‐55) based on 1,2,4‐triazole and terephthalic acid (bdc)/NH2‐bdc ligands were assembled and display framework stabilities, to a certain degree, in both acid/alkaline solutions and toward water. They exhibit high CO2 uptakes and selective CO2/N2 adsorption capacities, with CO2/N2 selectivity in the range of 24–27, as calculated by the ideal adsorbed solution theory method. More remarkably, the site and interactions between the host network and the CO2 molecules were investigated by single‐crystal X‐ray diffraction, which showed that the main interaction between the CO2 molecules and PMOF‐55 is due to multipoint supramolecular interactions of C?H???O, C???O, and O???O. Amino functional groups were shown to enhance the CO2 adsorption and identified as strong adsorption sites for CO2 by X‐ray crystallography. 相似文献