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81.
微乳凝胶中小分子传质研究   总被引:1,自引:0,他引:1  
微乳凝胶中小分子传质研究对于拓宽胶束酶学研究内涵、加速酶在生物合成与转化领域中的应用、研制高性能生物传感器等具有重要理论意义和潜在应用价值.以微乳液中二价金属离子与紫脲酸胺之间的配位反应为指示反应,采用分光光度技术,研究了金属离子在由阳离子表面活性剂十六烷基三甲基溴化胺构建的微乳凝胶中的传质问题.结果表明,在由含紫脲酸胺微乳液及含金属离子微乳凝胶构成的体系中,金属离子在微乳凝胶中的传质是金属离子与紫脲酸胺配位反应的限速步骤.为进一步证实上述结论,还对影响金属离子在微乳凝胶中传质的各种因素(如微乳液中水与表面活性剂的摩尔比值、分散相中甘油与水的配比等)进行了研究,结果也证实了上述结论.  相似文献   
82.
The title complex 1, C28H26CoN4O2, crystallizes in the triclinic system, space group P-1 with a = 9.506(3), b = 9.506(3), c = 14.837(5) A, α = 106.397(5), β = 106.012(5), γ =91.889(6)°, V = 1217.7(7) A3, Z = 2, Dc=1.390 g/cm3, Mr= 509.46, F(000) = 530,μ(MoKα) =0.738 mm-1, the final R = 0.0359 and wR = 0.0951 for 4275 observed reflections with I > 2σ(I).The complex adopts a distorted tetrahedral coordination sphere around the cobalt atom.  相似文献   
83.
To investigate the effects of metal–ligand coordination on the molecular structure, internal structure, dimensions, and morphology of self‐assembled nanostructures, two nonperipherally octa(alkoxyl)‐substituted phthalocyanine compounds with good crystallinity, namely, metal‐free 1,4,8,11,15,18,22,25‐octa(butyloxy)phthalocyanine H2Pc(α‐OC4H9)8 ( 1 ) and its lead complex Pb[Pc(α‐OC4H9)8] ( 2 ), were synthesized. Single‐crystal X‐ray diffraction analysis revealed the distorted molecular structure of metal‐free phthalocyanine with a saddle conformation. In the crystal of 2 , two monomeric molecules are linked by coordination of the Pb atom of one molecule with an aza‐nitrogen atom and its two neighboring oxygen atoms from the butyloxy substituents of another molecule, thereby forming a Pb‐connected pseudo‐double‐decker supramolecular structure with a domed conformation for the phthalocyanine ligand. The self‐assembling properties of 1 and 2 in the absence and presence of sodium ions were comparatively investigated by scanning electronic microscopy (SEM), spectroscopy, and X‐ray diffraction techniques. Intermolecular π–π interactions between metal‐free phthalocyanine molecules led to the formation of nanoribbons several micrometers in length and with an average width of approximately 100 nm, whereas the phthalocyaninato lead complex self‐assembles into nanostructures also with the ribbon morphology and micrometer length but with a different average width of approximately 150 nm depending on the π–π interactions between neighboring Pb‐connected pseudo‐double‐decker building blocks. This revealed the effect of the molecular structure (conformation) associated with metal–ligand (Pb? Nisoindole, Pb? Naza, and Pb? Obutyloxy) coordination on the dimensions of the nanostructures. In the presence of Na+, additional metal–ligand (Na? Naza and Na? Obutyloxy) coordination bonds formed between sodium atoms and aza‐nitrogen atoms and the neighboring butyloxy oxygen atoms of two metal‐free phthalocyanine molecules cooperate with the intrinsic intermolecular π–π interactions, thereby resulting in an Na‐connected pseudo‐double‐decker building block with a twisted structure for the phthalocyanine ligand, which self‐assembles into twisted nanoribbons with an average width of approximately 50 nm depending on the intertetrapyrrole π–π interaction. This is evidenced by the X‐ray diffraction analysis results for the resulting aggregates. Twisted nanoribbons with an average width of approximately 100 nm were also formed from the lead coordination compound 2 in the presence of Na+ with a Pb‐connected pseudo‐double‐decker as the building block due to the formation of metal–ligand (Na? Naza and Na? Obutyloxy) coordination bonds between additionally introduced sodium ions and two phthalocyanine ligands of neighboring pseudo‐double‐decker building blocks.  相似文献   
84.
In most cases, borylenes containing boron (I) are unstable. In this article, we proceed from the electron configuration of borylene and review the common methods of stabilizing this category of compounds through a series of borylenes in literature. In addition, the article briefly introduces the metallic borylenes and non-metallic borylenes and their properties. Some of these properties have been applied in nitrogen fixation.  相似文献   
85.
本文对Ln(phen)(C6H5COO)3、Ln(phen)2P-(OC6H4CHO)3·3H2O.Ln(phen)2P-(OC6H4COOC2H5)3(Ln=Tb、Eu)固体配合物的制备和光谱性质进行了研究。根据元素分析、红外光谱、摩尔电导测定,X射线粉末衍射、热重差热分析以及紫外可见光谱确定了其组成及配位形式,并对其发光性能进行了研究。  相似文献   
86.
A 1-D chain complex, cadmium(ΙΙ) chloride thiocyanate (1), [CdCl(SCN)] n was synthesized by evaporation and characterized by single-crystal X-ray diffraction and FT-IR techniques. The compound crystallizes in the space group Pnma of orthorhombic system with cell parameter a = 9.5967(7), b = 4.2595(3), and c = 10.1789(7) Å; V = 416.08(5) Å3 and Z = 4. The cadmium(ΙΙ) is five-coordinate, surrounded by one pair of (µ-1,1-NCS) bridging NCS? and three Cl? as a µ3-linker coordinating three Cd(ΙΙ) centers, approximately a severely distorted square-pyramidal configuration. Cd(ΙΙ), Cl?, and SCN? form an infinite 1-D chain with chair-like features, a new example of mixed Cd–NCS–Cl discrete compounds. The photophysical properties of the crystals have been investigated with one emission peak at 473 nm observed for the title complex in the solid state, which exhibits blue luminescence. The mechanical properties of the crystals have been studied using Vickers microhardness tester and the hardness was 78.6 kg mm?2.  相似文献   
87.
The neutral, mononuclear complex [ReO(mta)2Cl] (1) [Hmta?=?2-(methylmercapto)aniline] was prepared by reaction of trans-[ReOCl3(PPh3)2] with a twofold molar excess of Hmta in methanol. The oxo-bridged dimer (μ-O)[ReO(mta)2]2 (2) was synthesized by reacting [ReOCl3(PPh3)2] with a twofold excess of Hmta in a 9?:?1 acetone/water mixture. The compounds were characterized by spectroscopy and complex 1 also by X-ray crystallography. Complex 1 has a distorted octahedral geometry with the chloride coordinated trans to the oxo group, and with the chelating ligands in the equatorial plane in a cis-N cis-S configuration.  相似文献   
88.
[Yb2(SBTC)(ox)(H2O)5] n (1) (H4-SBTC?=?5-sulfonyl-1,2,4-benzenetricarboxylic acid and ox?=?oxalate) has been hydrothermally synthesized by reaction of 5-sulfonyl-1,2,4-benzenetricarboxylic acid with Yb(NO3)3?5H2O. In situ formation of oxalate derived from H4-SBTC is unprecedented and adds a new oxalate formation reaction to in situ ligand syntheses. Compound 1 features a 2-D bilayered coordination network, which is further extended into a 3-D supramolecular framework through interlayered hydrogen bonds. Magnetic measurements on 1 indicate that there is an antiferromagnetic interaction between Yb(III) ions.  相似文献   
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