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101.
L. A. Gribov I. A. Novakov A. I. Pavlyuchko E. V. Vasiliev 《Journal of Structural Chemistry》2007,48(6):1015-1021
The CH bond dissociation energies were determined for the bromo derivatives of methane, ethane, propane, cyclopropane, ethane, propene, and benzene by the spectroscopic and quantum-chemical methods. The spectroscopic values of the CH bond dissociation energies were obtained from the fundamental absorption bands by the variational method in an anharmonic approximation using the Morse-harmonic basis. Quantum-chemical calculations were performed using the 6-311G(3df, 3pd)/B3LYP basis. The resulting tendencies of variation of the bond dissociation energies due to changes in the molecular structure are discussed. 相似文献
102.
Four mercury(II) thiocyanate–organic polymeric complexes, [Hg(μ-4,4-bipy)(SCN)2]n (1), [Hg(μ-bpa)(SCN)2]n (2), [Hg(μ-bpe)(SCN)2]n (3), [Hg(μ-bpp)(SCN)2]n (4) {4,4-bipy = 4,4′-bipyridine, bpa = 1,2-bis(4-pyridyl)ethane, bpe = 1,2-bis(4-pyridyl)ethene and bpp = 1,3-di(4-pyridyl)propane} were prepared from reactions of mercury(II) thiocyanate with four rigid and flexible organic nitrogen donor-based ligands under thermal gradient conditions, brunched tube method. All these compounds were structurally determined by X-ray single-crystal diffraction. The thermal stabilities of compounds 1–4 were studied by thermal gravimetric (TG) and differential thermal analyses (DTA). Solid state luminescent spectra of compounds 1 and 3 indicate intense fluorescent emissions at 430 and 468 nm, respectively. 相似文献
103.
利用联苯四羧酸(H4bptc)和双三唑乙烷(bte)合成了2个配位聚合物{[Zn2(bptc)(DMF)2(H2O)]·DMF·H2O}n(1)和{[Zn(bte)(bptc)0.5]·DMF·0.5H2O}n(2)。化合物1为三维Pt S-拓扑结构,在该配合物中每个双核次级构筑单元(SBU){Zn2(O2CR)4}与4个联苯四酸配体相连,从而将配合物构筑成了三维MOF结构。化合物2为二维梯形结构,并通过弱氢键O…H-C将二维层连接为三维结构。同时对配合物的热稳定性和荧光特征进行了讨论。 相似文献
104.
Identifying Different Types of Catalysts for CO2 Reduction by Ethane through Dry Reforming and Oxidative Dehydrogenation 下载免费PDF全文
Dr. Marc D. Porosoff Myat Noe Zin Myint Dr. Shyam Kattel Zhenhua Xie Elaine Gomez Dr. Ping Liu Prof. Dr. Jingguang G. Chen 《Angewandte Chemie (International ed. in English)》2015,54(51):15501-15505
The recent shale gas boom combined with the requirement to reduce atmospheric CO2 have created an opportunity for using both raw materials (shale gas and CO2) in a single process. Shale gas is primarily made up of methane, but ethane comprises about 10 % and reserves are underutilized. Two routes have been investigated by combining ethane decomposition with CO2 reduction to produce products of higher value. The first reaction is ethane dry reforming which produces synthesis gas (CO+H2). The second route is oxidative dehydrogenation which produces ethylene using CO2 as a soft oxidant. The results of this study indicate that the Pt/CeO2 catalyst shows promise for the production of synthesis gas, while Mo2C‐based materials preserve the C? C bond of ethane to produce ethylene. These findings are supported by density functional theory (DFT) calculations and X‐ray absorption near‐edge spectroscopy (XANES) characterization of the catalysts under in situ reaction conditions. 相似文献
105.
1,2-Bis(benzimidazol-2-yl)ethane (bbe) and its copper(II) complex, {[Cu(bbe)Br2]2}·2DMF ( 1 ), have been synthesized and characterized by elemental analysis, ultraviolet–visible, and infrared spectra. The single crystal structure analysis of 1 shows two crystallographically independent but chemically identical [Cu(bbe)Br2] molecules. The coordination geometry of the copper atoms may best be described as a distorted tetrahedron (τ4 = 0.740 for Cu1 and 0.696 for Cu2). The cyclic voltammogram of complex 1 represents quasi-reversible Cu2+/Cu+ pairs. in vitro antioxidant tests showed that complex 1 has significant antioxidant activity against superoxide and hydroxy radicals. Photoluminescence investigations showed that the fluorescence intensity of complex 1 is significantly weaker than that of the ligand. This may be due to the paramagnetic effect of divalent copper to cause quenching of fluorescence. 相似文献
106.
Syntheses and characterization of energetic compounds constructed from alkaline earth metal cations (Sr and Ba) and 1,2-bis(tetrazol-5-yl)ethane 总被引:4,自引:0,他引:4
Two new energetic compounds, [M(BTE)(H2O)5]n (M=Sr(1), Ba(2)) [H2BTE=1,2-bis(tetrazol-5-yl)ethane], have been hydrothermally synthesized and structurally characterized. Single-crystal X-ray diffraction analyses reveal that they are isomorphous and exhibit 2D (4,4) net framework, generated by 4-connected Sr2(H2O)10/Ba2(H2O)10 SBUs linked up by two independent binding modes of H2BTE, and the resulting 2D structure is interconnected by hydrogen-bond and strong face to face π-π stacking interactions between two tetrazole rings to lead to a 3D supramolecular architecture. DSC measurements show that they have significant catalytic effects on thermal decomposition of ammonium perchlorate. Moreover, the photoluminescence properties, thermogravimetric analyses, and flame colors of the as-prepared compounds are also investigated in this paper. 相似文献
107.
Eduard B. CoropceanuMark M. Botoshansky Anatolii V. SiminelMarina S. Fonari 《Polyhedron》2011,30(15):2592-2598
The reaction of copper(II) acetate or fluoride with classic dioximes in the presence of 1,2-bis(4-pyridyl)ethane resulted in four novel compounds with the compositions [Cu2(dmgH)4bpe] (1), [Cu2(NioxH)4bpe] (2), [Cu2(dpgH)4bpe] (3), and [Cu2(dpgH)4bpe][Cu(dpgH)2bpe]2·2DMF (4) (where dmgH2 = dimethylglyoxime, NioxH2 = 1,2-cyclohexanedionedioxime, dpgH2 = diphenylglyoxime, bpe = 1,2-bis(4-pyridyl)ethane, and DMF = N,N′-dimethylformamide), whose crystal structures were determined by single crystal X-ray diffraction. In the binuclear molecules 1-3, as well as in both binuclear and mononuclear molecules in 4 each Cu(II) atom has an identical N5-environment formulated by four oximic nitrogen atoms of two monodeprotonated ligands in a slightly distorted square planar mode, and the nitrogen atom of the bpe molecule being in the apical position. The new compounds were characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. Luminescence investigations for 1, 2 and 4 were carried out to clarify whether the guest inclusion in the crystal lattice is accompanied by changes in the emission spectra. 相似文献
108.
《Journal of Coordination Chemistry》2012,65(16):1807-1811
The complexes [M(CO)4(η2-H2L)] [M?=?Cr; 1, Mo; 2, W; 3] have been synthesized by photochemical reactions of VIB metal carbonyls [M(CO)6] [M?=?Cr,?Mo,?W] with N,N′-bis(salicylidene)-1,2-bis-(o-aminophenoxy)ethane (H2L) in THF and characterized by elemental analyses, FTIR, 1H?NMR and mass spectra. The H2L ligand is coordinated to the central metal as a bidentate ligand via the central azomethine nitrogen atoms in 1–3. 相似文献
109.
建立了凝胶渗透色谱(GPC)去脂,气相色谱-负化学电离源-质谱(GC-NCI-MS)法测定人血清中2,2’,4,4’,5,5’-六溴联苯(BB-153)、1,2-二(2,4,6-三溴苯氧基)乙烷(BTBPE)和德克隆(Dechlorane plus,DP,包括syn-DP和anti-DP)的方法。人血清样本加入内标13C12BB-153和13C10syn-DP,经蛋白质变性、脂肪提取、GPC去脂、酸性硅胶柱净化后,利用气相色谱-负化学电离源-质谱法测定样品中BB-153,BTBPE,syn-DP和anti-DP,监测离子分别为m/z 627.5,629.5,m/z 79,81以及m/z 652,654。结果表明,13 C12 BB-153和13 C10syn-DP的血清加标回收率分别为91.5%±8.9%和92.3%±8.1%,检出限为0.6~1.2 ng/g脂肪。应用本方法对人血样品进行测定,BB-153和BTBPE在所有样本中均未检出,syn-DP和anti-DP的浓度范围分别是0.7~9.2 ng/g脂肪和0.6~2.0 ng/g脂肪。 相似文献
110.