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991.
合成了一个多功能的配体1H-3-(3-吡啶)-5-(3'-吡啶)-1,2,4-三唑(3,3'-Hbpt,1)并得到了配体的晶体结构,运用DFT理论计算了配体的最优构型、优势构象和电荷分布。在此基础上,水热合成了一个配位化合物:[Co(3,3'-Hbpt)2(H2O)4]·(ad)·6H2O(2)(ad=己二酸),结构分析表明配合物2是零维单核化合物,它的三维超分子结构是由分子间氢键连接而成,其中包含着由游离的己二酸分子填充的矩形孔道。值得注意的是,配体在配合物中的几何结构和构象与理论计算的结果一致。另外,利用热重分析研究了配合物2的热稳定性。 相似文献
992.
通过水热法合成了2个配位聚合物:[Cu(H2dpcp)2]n(1)和[Mn2(Hdpcp)2(H2O)2·2H2O]n(2)[H3dpcp=5-(2,4-二羧基苯基)-2-羧基吡啶],H3dpcp由3-(2,4-二羧基苯基)-2,6-二羧基吡啶(H4dpdp)原位脱羧生成。X-射线单晶衍射测得2个化合物都属于单斜晶系,化合物1结晶在P21/c空间群,a=0.639(13)nm,b=1.835(4)nm,c=1.115(2)nm,β=102.29(3)°,Z=2;化合物2结晶在C2/c空间群,a=3.126(6)nm,b=1.004(2)nm,c=1.080(2)nm,β=93.73(3)°,Z=4。化合物1以配体H2dpcp-桥连Cu( Ⅱ)形成一维链状结构。化合物2通过Hdpcp2-桥连Mn( Ⅱ)形成二维层状结构,并进一步通过氢键作用形成三维超分子结构。负的Weiss常数θ表明化合物2存在反铁磁耦合作用。 相似文献
993.
994.
由1,1'-双苄基-3,3'-氧双(亚乙基-2,1)-二苯并咪唑六氟磷酸盐(L1)和1,1'-双(吡啶-2-甲基)-3,3'-氧双(亚乙基-2,1)-二苯并咪唑六氟磷酸盐(L2)为配体合成了[Hg(C32H28N4O)](CH3COO)(PF6)2(1)和[NiCl(C30H28N6O)](PF6)2(2),并对其进行了结构表征。配合物1是一个罕见的三价态Hg配合物,为单斜晶系P21/c空间群,配合物2为单斜晶系P21/n的配合物。1和2中存在O-H…F,C-H…F,C-H…Cl,C-H…π,P-F…π氢键作用和π-π堆积作用,并以此分别形成了3D超分子结构。 相似文献
995.
用化学修饰法制备出复合物多壁碳纳米管/聚丙烯酸(MWCNTs/PAA),用溶剂热法合成Zn4O(1,4-benzenedicarboxylate)3(MOF-5)和MWCNTs/PAA/MOF-5。通过XRD、FTIR、TG、HRTEM和比表面积和孔隙度分析仪对MWCNTs,MOF-5,MWCNTs/PAA和MWCNTs/PAA/MOF-5的结构和性质进行表征。结果表明:复合材料MWCNTs/PAA中PAA包覆在碳纳米管外壁上,含量为4.3%,在FTIR中有PAA特征官能团的吸收峰;MWCNTs/PAA/MOF-5和MOF-5的形貌一样,MWCNTs/PAA/MOF-5的热分解温度比MOF-5的提高了49℃;MOF-5和MWCNTs/PAA/MOF-5的N2吸附曲线为Ⅰ型,77 K和100 k Pa条件下,N2的吸附量达到最大值,分别为265、299.03 cm3·g-1。 相似文献
996.
Yarabally R Girish Kanchipura R Raghavendra Dasappa Nagaraja Kothanahally S Sharath Kumar Sheena Shashikanth 《中国化学》2015,33(2):181-184
An efficient, inexpensive and simple method for the reduction of various α,β‐unsaturated ketones to corresponding saturated ketones using tosyl hydrazide as a hydrogen donor in DMF using calcium oxide powder has been reported. A variety of enones underwent reduction without forming undesirable side products. High chemoselectivity, broad functional group tolerance and good yields are the noteworthy features of this protocol. 相似文献
997.
Selective oxidation of sulfides to sulfoxides was successfully performed by employing readily available Fe(NO3)3·9H2O as the active catalyst with oxygen as the oxidant in 2,2,2-trifluoroethanol (TFE) without the formation of sulfones. Nitrate anion could play a crucial role in promoting the reaction due to the oxidation capacity under acidic media. High yields of sulfoxides were exclusively obtained from the corresponding sulfides. Furthermore, both aromatic and aliphatic sulfides gave moderate to high yields of sulfoxides with this protocol. 相似文献
998.
An efficient method for the synthesis of benzo[b]benzofurano[2,3-e][1,6]naphthyridine-8-one derivatives has been developed via Pictet-Spengler reaction of 4-(3-aminobenzofuran-2-yl)quinoline-2-ones,which could be obtained from alkylation of 4-bromomethylquinoline-2-ones with salicylonitrile and subsequent Thorpe-Ziegier isomerization,with aromatic aldehydes under p-TsOH as catalyst in good yields. 相似文献
999.
Lanthanum modified materials have been widely used for the removal of hazardous anions.In this study,in situ ATR-FTIR and two-dimensional correlation analysis were employed to investigate the adsorption mechanism of arsenate(As(V)) on lanthanum-impregnated activated alumina(LAA).Our results showed that electrostatic interaction attracted As(V) anions to the LAA surface,and then As(V) could form monodentate configuration on the LAA surface at pH 5-9.The result of 2D-COS showed that two coexistent adsorbed As(V) species,H2AsO4- and HAsO42-,were adsorbed on the LAA surface without specific sequence at different pH conditions,indicating a negligible role of the incorporated protons of As(V) on the adsorption affinity to LAA surface.The results of this study reveal insights into LAA surface complexes on the molecular scale and provide theoretical support to new metal oxides design for efficient arsenic removal. 相似文献
1000.
Metal binding of organic ligands can definitely affect its environmental behavior in waters, while information on the binding heterogeneity with different organic ligands is still lacked till now. In this study, the binding of zinc with organic matters associated with cyanobacterial blooms, including dissolved organic matters (DOM) and attached organic matters (AOM), were studied by using fluorescence quenching titration combined with two-dimensional correlation spectroscopy (2D-COS). Metal-induced fluorescent quenching was obviously observed both for DOM and AOM, indicating the formation of metal-ligand complexes. Compared with the one-dimensional spectra, 2D-COS revealed the sequences of metal-ligand interaction with the following orders: 276 nm > 232 nm for DOM and 232 nm > 276 nm for AOM. Furthermore, the modified Stern-Volmer model showed that the binding constant (log KM) of 276 nm in DOM was higher than that of 232 nm (4.93 vs. 4.51), while AOM was characterized with a high binding affinity for 232 nm (log KM: 4.83). The ranks of log KM values were consistent with the sequential orders derived from 2D-COS results both for the two samples. Fluorescence quenching titration combined with 2D-COS was an effective method to characterize the metal-ligand interaction. 相似文献