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91.
含偶氮苯的咔唑类双功能光折变聚合物的合成及表征 总被引:1,自引:1,他引:1
通过后重氮偶合方法制备了一系列不同生色团含量的咔唑类双功能光折变聚合物,并用IR、^1H-NMR、UV-vis、DSC以及GPC等对聚合物进行了分析和表征。IR和UV-vis谱图显示偶氮苯基团已接到咔唑环上。UV-vis结果表明:反应时间对该反应的影响非常大,当反应时间从6h增加到60h时,聚合物中生色团的含量从13.5%升高到66.7%。GPC结果显示后重氮偶合法比常规方法得到的该类聚合物的分子量明显提高。DSC结果显示聚合物的玻璃化转变温度随偶氮苯含量的增加而升高。 相似文献
92.
The aim of this research is to achieve the synthesis of a novel mono azo disperse dye containing both a β‐naphthyl acetate group and carboxylic acid ester group and application on PET fabric. In this study the dyeing properties have also been investigated. The synthesized dye was characterized using UV‐Vis, FTIR, 1H NMR and 13C NMR spectroscopic techniques. To investigate alkali‐clearability, both alkali‐hydrolysis behavior and the effect of its fastness properties with regard to PET fabric were examined. This dye showed a reasonable level of hydrolysis under relatively mild alkaline conditions. The application of the dye to PET fabric showed good leveling and building up properties. Estimating fastness properties of the dyed fabric showed excellent wash, rubbing fastness, good light and sublimation fastness. The results furthermore displayed that the synthesized dye offers the option of alkali‐clearing process over that of a conventional reduction‐clearing process. Therefore, the value of Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD) and water pollution as well as the expenditure of production were decreased. 相似文献
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Commentary on “Caged Phosphate and the Slips and Misses in Determination of Quantum Yields for Ultraviolet‐A‐Induced Photouncaging” by G. Gasser and Co‐Workers 下载免费PDF全文
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N. I. Baram Kh. L. Ziyaev A. I. Ismailov D. Ziyamov Yu. S. Mangutova 《Chemistry of Natural Compounds》2000,36(2):185-188
New azo derivatives of gossypol are described. Their physicochemical properties are reported. The presence of hydroxyazo- and quinonhydrazo-tautomers is proposed.A. S. Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (99871) 162 70 71. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 145–148, March–April, 2000. 相似文献
98.
Long Giang BachMd. Rafiqul Islam Yeon Tae JeongYeong Soon Gal Kwon Taek Lim 《Applied Surface Science》2012,258(7):2816-2822
The synthesis of chemically anchored adenosine with biocompatible poly(2-hydroxylethyl methacrylate) grafted gold nanoparticles (Ado-i-PHEMA-g-AuNPs) was realized by employing a simple strategy. Disulfide-containing poly(2-hydroxylethyl methacrylate) (DT-PHEMA) was initially synthesized by atom transfer radical polymerization (ATRP). The formation of DT-PHEMA was confirmed by 1H-NMR and FT-IR. The molecular weight and molecular weight distribution were found to be 9.6 kg/mol and 1.40 from GPC analysis. DT-PHEMA was subsequently used for the synthesis of PHEMA-g-AuNPs by a grafting to protocol. The grafting of DT-PHEMA on the surface of AuNPs was confirmed by FT-IR, TGA, XPS, and EDX analyses. The particle size of the PHEMA-g-AuNPs was found to be ca. 5.0 nm from HR-TEM analysis. Boronic acid was used for functionalization of PHEMA-g-AuNPs, which was then subjected for covalent immobilization with adenosine via strong interaction between free hydroxyl groups of adenosine and boronic acid. Characterization and properties of the Ado-i-PHEMA-g-AuNPs were investigated by taking advantage from FT-IR, XPS, EDX, and UV-visible spectroscopy. The Ado-i-PHEMA-g-AuNPs nanocomposite exhibits a surface plasmon resonance peak at 586 nm which is red shifted from AuNPs (521 nm), indicating significant changes of surface property upon PHEMA-adenosine immobilization onto the surface of AuNPs. 相似文献
99.
Xiaohua He Chunyan Gao Wuqiong Sun Wei Huang Shaoliang Lin Deyue Yan 《Journal of polymer science. Part A, Polymer chemistry》2013,51(5):1040-1050
Well‐defined azobenzene‐containing side‐chain liquid crystalline diblock copolymers composed of poly[6‐(4‐methoxy‐azobenzene‐4′‐oxy) hexyl methacrylate] (PMMAZO) and poly(γ‐benzyl‐L ‐glutamate) (PBLG) were synthesized by click reaction from alkyne‐ and azide‐functionalized homopolymers. The alkyne‐terminated PMMAZO homopolymers were synthesized by copper‐mediated atom transfer radical polymerization with a bromine‐containing alkyne bifunctional initiator, and the azido‐terminated PBLG homopolymers were synthesized by ring‐opening polymerization of γ‐benzyl‐L ‐glutamate‐N‐carboxyanhydride in DMF at room temperature using an amine‐containing azide initiator. The thermotropic phase behavior of PMMAZO‐b‐PBLG diblock copolymers in bulk were investigated using differential scanning calorimetry and polarized light microscopy. The PMMAZO‐b‐PBLG diblock copolymers exhibited a smectic phase and a nematic phase when the weight fraction of PMMAZO block was more than 50%. Photoisomerization behavior of PMMAZO‐b‐PBLG diblock copolymers and the corresponding PMMAZO homopolymers in solid film and in solution were investigated using UV–vis. In solution, trans–cis isomerization of diblock copolymers was slower than that of the corresponding PMMAZO homopolymers. These results may provide guidelines for the design of effective photoresponsive anisotropic materials. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
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