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31.
气液色谱法是研究酸碱相互作用热力学性质的有效方法之一,适合于气液表面化学反应的研究,可以得到一些用其他方法难以获得的热力学参数,丰富了表面化学领域的研究,具有重要的理论意义和应用价值。文献[1—4]利用气液色谱法测量了Ni[THDD]_2、Ni[(C_8H_(17)O)_2PS_2]_2与含氮、含氧有机碱加合反应的平衡常数、标准焓变和标准熵变值。作为酸碱加合反应研究的一部份,本文测定了Ni[C_8H_(17)O)_2PS_2]_2与五员杂环化合物呋喃、噻吩和吡咯反应的热力学参数。 相似文献
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0IntroductionThereisagreatcurrentinterestforthecrystalengineeringofcoordinationframeworks犤1,2犦,notonlybecauseoftheirpotentialapplicationsaszeolite-likematerialsinmolecularselection,ionexchange,andcatalysis,butalsobecauseoftheirintriguingvarietyofarchitecturesandnewtopologies.Uptonow,themostimportantdrivingforcesincrystalengineeringarecoordinationbondingandhydrogenbondinginteract-ion犤3~5犦.Theuniquedirectionality,strength,andcom-plementaryofnon-covalenthydrogenandcoordinatedbondingplayanimp… 相似文献
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合成了六个含氮杂环桥联配合物:[Ni(salal)_2(4,4’-bipy)]_n、[Ni(Et-dtp)_2(4,4’-bipy]_n、[Cu-(acac)_2(4,4’-bipy)]_n、[Cu(TTA)_2(pyz)]_n、[Cu(TTA)(Im)]_n和[Cu(Im)_2]_n,用元素分析、IR、MS、ESR和热重分析对它们的结构和性质作了表征.吡嗪配合物的晶体结构显示,吡嗪配位于拉伸八面体的轴向位置,桥联Cu(TTA)_2形成一维无限链状结构.变温磁化率表明,4,4’-联吡啶和吡嗪配合物的磁性遵从Curie-Weiss定律,分子内没有明显的磁交换作用.咪唑配合物中存在着较强的反铁磁性交换作用,磁交换常数分别为-75和-107cm~(-1).对4,4’-联吡啶、吡嗪和咪唑传递磁交换的性质作了讨论. 相似文献
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亚微米级Ag2S空心球的乳液法合成 总被引:4,自引:0,他引:4
Hollow Ag2S spheres have been prepared via hydrolyze reaction of Ag2S2O3, which formed from the reaction of AgNO3 with Na2S2O3, in cyclohexane/water/polyglycol emulsion system. It was found that the component of the reaction system has a significant influence on the formation of hollow Ag2S spheres. The possible formation mech-anism of the hollow Ag2S spheres in the emusion system was also discussed. 相似文献
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The synthesis of nickel supramolecular compound with hexamethylenetetramine and fumarate ligands is reported. The compound [Ni(H2O)6(fum)]·2(hmt)·4H2O (1) (fum=fumarate; hmt=hexamethylenetetramine) were characterized by elemental analysis, crystal structure, IR. Compound 1 crystallizes in the triclinic system, space group P1, and with Z=1. Cell parameters: a=0. 934 6(1), b=0.933 8(1), c=0.938 8(2) nm, α=79.46(1)°, β=77.84(1)°, γ=61.29 6(7)°. Every metal ion has a octahedral coordination geometry formed by six oxygen atoms from six water molecules, and the relative independent components [Ni(H2O)6]2+, fumarate anions, hmt and H2O molecules are linked together by two kinds of hydrogen bonds (O-H…O, and O-H…N) to form a three-dimensional structure. CCDC: 256355. 相似文献
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The novel complex {[Co(bipy)(azpy)2(NCS)2]·H2O}n (where bipy=4,4′-bipyridine, azpy=4,4′-azobisp- yridine) has been synthesized and characterized by elemental analyses, IR, UV, thermal analyses, and vari-able-temperature magnetic susceptibility. The crystal (C32H26CoN12OS2, Mr=717.70) belongs to the orthorhombic, space group Pnna, a=2.21312(16)nm, b=1.40403(10)nm, c=1.14237(8)nm, V=3.5497(4)nm3, Z=4, Dc=1.343g·cm-3, μ=0.645mm-1, F(000)=1476, and final R1=0.0691, wR2=0.1129 for 231 parameters and 1674 observed reflections [I >2.00σ(I)]. The Co(Ⅱ) atom is, in a distorted octahedral geometry, coordi-nated by six nitrogen atoms from two bridging bipy, two monodentate azpy, and two thiocyanate groups. The bridging ligand bipy links Co(Ⅱ) atoms to form the infinite “rod" with terminal coordination azpy ligand acting as sidearms. Unprecedented three parallel interpenetrating two-dimensional (4,4) networks and novel infinite triple helices are formed via hydrogen-bonding interactions. CCDC: 155588. 相似文献
40.
Binuclear Copper (Ⅰ) Complex {Cu[μ-S2P(C2H5O)2](C10H8N2)}2 was synthesized and characterized by elemental analysis, IRand X-ray diffraction analysis.The crystal belongs to triclinic system, space group P1 with Z = 1, cell dimentions are a = 1.0613 (5), b = 1.0723 (3), c = 0.9397 (2) um, a = 111.11 (4), β = 115.57(6), γ = 85.28(2)°, V= 0.8583(6) nm3.The structure was refined to R = 0.039 and Rw = 0.042 for 2527 reflection with Ⅰ≥3σ(Ⅰ).The complex exists as a centrosymmetric dimer with a Cu-S-P-S-Cu-S-P-Schair eight-membered ring in which Cu atoms are bridged by di-μ-S-P-Sgroups. 相似文献