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Four metal-organic coordination compounds containing ferrocenylthiocarboxylate components, [Cd2(η2-SOCFc)2(η1-μ2-SOCFc)2(4,4′-bpy)]n (1), [Cd(SOCFc)2(tmp)]n (tmp = 4,4′-trimethylene-dipyridine) (2) [Zn(SOCFc)2(2,2′-bpy)] (3), and {[Hg(SOCFc)2(phen)] · (0.5CH3OH)} (4) (Fc = (η5-C5H5)Fe(η5-C5H4)), have been prepared in search of good nonlinear optical (NLO) materials. Investigation of the NLO properties shows that Hg-containing compound 4 exhibits very strong third-order NLO absorptive and refractive effects. The NLO absorptive coefficient α2 value (2.11 × 10−10 m W−1) is larger than those of all the reported ferrocenylcarboxylate-containing coordination compounds and comparable to the well-performing Hg-containing complexes. Additionally, we further analyzed their NLO behaviors through studying electrochemical properties of the four compounds. 相似文献
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With the motivation of searching for highly selective ferric ion sorbents, two open-framework and microporous materials, {[Pb7(HEDTP)2(H2O)] x 7H2O}n (1) and {[Zn2(H4EDTP)] x 2H2O}n (2) [H8EDTP = N,N,N',N'-ethylenediaminetetrakis(methylenephosphonic acid)], have been synthesized and structurally characterized. The structure of compound 1 results from the seven crystallographically different lead atoms that are bridged by two HEDTP(7-) ligands to yield a three-dimensional microporous framework with tunnels along the a and b axes. Compound 2 features a layer architecture built of square waves along the a axis. The layers are connected by hydrogen bonds between uncoordinated phosphonate oxygen atoms to form a three-dimensional supramolecular network, with one-dimensional tunnels along the a axis. Both compounds 1 and 2 exhibited high ion sorption and exchange capacities for millimolar concentrations of Fe(III). Specifically, when 0.01 g of 1 (or 2) was added to 5 mL of a 1 mM metallic chloride aqueous solution and the mixture was allowed to stand for 2 days at room temperature, compound 1 adsorbed nearly 100% of Fe(III) and compound 2 adsorbed 96.8% of Fe(III). They were also found to adsorb ferric ions selectively over other metal ions, such as Ca(II), Cr(II), Mn(II), Cu(II), Zn(II), Cd(II), etc. Their special ferric ion uptake capacities may be attributed to the cation exchange, coordination bonding, and electrostatic attraction between ferric ions and metal phosphonates. 相似文献
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教学大纲里培养能力的提法亟待研讨 总被引:1,自引:1,他引:0
作者对现行的中学化学教学大纲(1986)里,所要求的逐步发展学生的观察能力、思维能力、实验能力和自学能方的提法,从化学教学法的理论基础的辩证唯物主义认识论、指导理论的自然科学方法论、知能结构的统一和发展以及初、高中学生的年龄特点(结合赞科夫的研究成果和使用范围)等方面进行分析之后,认为“观察-思维-实验”这个能力结构的缺欠较多,不利于提高化学教学质量和进行教学改革,很有必要开展研究和讨论。 相似文献
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The direct self-assembly of bis-(1-benzoimidazolymethylene)-(2,5-thiadiazoly)-disulfide (L) with CuSO4, Cu(NO3)2 and CuCl2 affords three novel supramolecular complexes: 1-D ladder-like chain complex {[Cu(SO4)(L)] · (CH3OH)}n (1), dimer complexes {[Cu(L)(CH3O)]2(NO3)2} · 2H2O (2) and [Cu(L)(Cl)(N3)]2 · 2CH3OH (3). The nature of the anions is the underlying reason behind the differences in the structures of this series of complexes. Furthermore, utilizing the coordinatively unsaturated complexes 2 and 3 as precursor complexes, two new derivative complexes [Cu(L)(NCS)(CH3O)]2 · 2CH3OH (2A) and [Cu(L)(ClO4)(N3)]2 · 2CH3OH (3A) are obtained by the addition and exchange reactions of complexes 2 and 3 with anions. X-ray crystallographic analysis shows that the two derivatives retain the skeletons of their precursor complexes, and the anions with the stronger coordination capacity only bind to the active position of precursor complexes. In addition, different from the obvious effects on the structures in the direct self-assembly of the metal and ligand, the change of counteranions has no great impact on the structures in the anion exchange reactions. We also study the catalytic activities of the complexes 2, 2A, 3, and 3A, which have similar skeletons, for the oxidative coupling polymerization of 2,6-dimethylphenol (DMP). And we find that the introductions of different coordination counterions produce significant impacts on the catalytic properties of these complexes. 相似文献
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质谱联用技术在生物大分子分析中的应用 总被引:1,自引:0,他引:1
本文评述了近年来质谱联用技术在生物大分子分析应用中的最新进展。着重评述了由于ESI接口的出现而推动的高效液相色谱一连续流动快速原子轰击质谱(HPLC-cfFABMS )、高效取代色谱一连续流动快速原子轰击质谱(HPDC-cfFABMS ) ,凝胶渗透色谱一诱导祸合等离子体质谱(GPC-1CPMS )、毛细管电泳一质谱(CE-MS )和毛细管电泳一飞行时间质谱(CE-TOFMS)等方面近两年的动向及成果。本文较广泛地展示了质谱联用技术在生物大分子分析中的重要作用和独特的地位。 相似文献
29.
StudyofPreparationandCharacteristicsofPyridoxalated PolyhemoglobinLiangShuguang;TongMingrong;PanJilunandYuYaoting(Institutefo... 相似文献
30.
A new tripodal compound, 1,1,1-tris(N-ethyl-N-phenylamino-carboxylmethoxymethyl) propane, has been synthesized and evaluated as an ionophore in PVC membrane electrode for the analysis of alkali and alkaline earth metal cations. The influence of the nature of the plasticizers (o-NPOE, DBP and DOP) and of the amount of incorporated ionophore on the characteristics of the electrode was discussed. Selectivity coefficients against alkali and alkaline earth metal cations were calculated. The electrodes based on the tripodal compound with o-NPOE and DBP as plasticizer gave good performance (slope, limits of detection) to lithium and sodium ions. The electrode plasticized with o-NPOE also exhibited near-Nernstian response to divalent ions: Ca(2+), Sr(2+) and Ba(2+). The electrode prepared with 3.9 mg ionophore, 185 mg o-NPOE, 92 mg PVC and 0.46 mg KTpClPB can be used as a Ca(2+) electrode. The influence of pH has also been studied. The electrodes exhibited better potential stability and operational lifetime of more than 3 months. 相似文献