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991.
Xi-Cun Wang Guo-Jun Yang Xiao-Dong Jia Zhang Zhang Yu-Xia Da Zheng-Jun Quan 《Tetrahedron》2011,67(18):3267-3272
The Biginelli 3,4-dihydropyrimidin-2(1H)-one was converted to various C2-multifunctionalized pyrimidines via the dehydrogenation and Mitsunobu reaction using amines, alcohols, phenols and carboxylic acids as nucleophiles. A possible mechanism was also proposed to rationalize the formation of products. 相似文献
992.
993.
Hui-Lu Wu Ke Li Tao Sun Fan Kou Fei Jia Jing-Kun Yuan Bin Liu Bao-Liang Qi 《Transition Metal Chemistry》2011,36(1):21-28
Tris(N-methylbenzimidazol-2-ylmethyl)amine (Mentb) and its two complexes, [Mn(Mentb)(DMF)(H2O)](pic)2
1 and [Zn(Mentb)(pic)](pic) 2 (pic = picrate), have been synthesized and characterized by physico-chemical and spectroscopic methods. Single crystal X-ray
diffraction revealed that the two complexes have different structures. In complex 1, the coordination sphere around Mn(II) is distorted octahedral, whereas in complex 2 the coordination sphere around Zn(II) is distorted trigonal bipyramidal. The DNA-binding properties of the free ligand and
its two complexes have been investigated by electronic absorption, fluorescence, and viscosity measurements. The results suggest
that the ligand and its two complexes bind to DNA via an intercalation binding mode, and their binding affinity for DNA follows
the order 1 > 2 > ligand. 相似文献
994.
Huilu Wu Fei Jia Fan Kou Bin Liu Jingkun Yuan Ying Bai 《Transition Metal Chemistry》2011,36(8):847-853
A new Schiff base ligand N-(2-hydroxylacetophenone)-3-oxapentane-1,5-diamine (HL) and its Ni complex, [Ni2(L)2(NO3)2], have been synthesized and characterized by physicochemical and spectroscopic methods. The X-ray crystal structure of [Ni2(L)2(NO3)2] shows it to be a dinuclear 2:2 complex, in which each Ni(II) atom is in a distorted octahedral geometry. The two Ni(II)
atoms are dibridged by two phenoxo ligands, forming a Ni2O2 parallelogram-type moiety. The interactions between free HL and the complex with calf thymus DNA have been investigated,
and the binding constant and linear Stern–Volmer quenching constant suggest that the two compounds bind to DNA via the intercalation
mode. The binding affinity of the complex was higher than that of HL. Antioxidant assays in vitro showed that the Ni(II) complex
possesses significant antioxidant activity. 相似文献
995.
Xiaoyu Jia Yi Han Xinli Liu Taicheng Duan Hangting Chen 《Spectrochimica Acta Part B: Atomic Spectroscopy》2011,66(1):88-92
The dispersive liquid-liquid microextraction (DLLME) combined with high performance liquid chromatography-inductively coupled plasma mass spectrometry for the speciation of mercury in water samples was described. Firstly methylmercury (MeHg+) and mercury (Hg2+) were complexed with sodium diethyldithiocarbamate, and then the complexes were extracted into carbon tetrachloride by using DLLME. Under the optimized conditions, the enrichment factors of 138 and 350 for MeHg+ and Hg2+ were obtained from only 5.00 mL sample solution. The detection limits of the analytes (as Hg) were 0.0076 ng mL−1 for MeHg+ and 0.0014 ng mL−1 for Hg2+, respectively. The relative standard deviations for ten replicate measurements of 0.5 ng mL−1 MeHg+ and Hg2+ were 6.9% and 4.4%, respectively. Standard reference material of seawater (GBW(E)080042) was analyzed to verify the accuracy of the method and the results were in good agreement with the certified values. Finally, the developed method was successfully applied for the speciation of mercury in three environmental water samples. 相似文献
996.
997.
Fu Y Li SJ Xu J Yang M Zhang JD Jiao YH Zhang JC Zhang K Jia YG 《Langmuir : the ACS journal of surfaces and colloids》2011,27(2):672-677
A facile and efficient approach has been developed to speed up the fabrication of LBL films through sequential dipping in vigorously agitated solutions. By this agitated-dipping (AD) LBL technique, the multilayer films of PAH and PSS were fabricated. The resulting films were explored by UV-vis spectroscopy, X-ray reflectivity, and AFM. Meanwhile, the comparison of the AD and conventional LBL films was made, which demonstrated that AD LBL can decrease dipping time by more than 15 times without reducing film quality remarkably. In addition, to verify the generality of AD LBL, we studied the AD LBL films of PDDA/PSS and PAH/PAA preliminarily as well. AD LBL promotes the efficiency of conventional LBL greatly while preserving its most advantages, such as simplicity, cheapness, precise control, universality in substrates, recycling use of sample solutions, and so on. It would be a promising alternative to build up LBL films rapidly. 相似文献
998.
Weiwei Tang Jingjing Liang Wenqing Jiang Bing Wu Dr. Yong Zhang Prof. Dr. Dingxian Jia 《无机化学与普通化学杂志》2011,637(11):1539-1544
The lanthanide selenidogermanates [{Eu(en)3}2(μ‐OH)2]Ge2Se6 ( 1 ), [{Ho(en)3}2(μ‐OH)2]Ge2Se6 ( 2 ), and [{Ho(dien)2}2(μ‐OH)2]Ge2Se6 ( 3 ) (en = ethylenediamine, dien = diethylenetriamine) were solvothermally prepared by the reactions of Eu2O3 (or Ho2O3), germanium, and selenium in en and dien solvents respectively. Compounds 1 – 3 are composed of selenidogermanate [Ge2Se6]4– anion and dinuclear lanthanide complex cation [{Ln(en)3}2(μ‐OH)2]4+ (Ln = Eu, Ho) or [{Ho(dien)2}2(μ‐OH)2]4+. The [Ge2Se6]4– anion is composed of two GeSe4 tetrahedra sharing a common edge. The dinuclear lanthanide complex cations are built up from two [Ln(en)3]3+ or [Ho(dien)2]3+ ions joined by two μ‐OH bridges. All lanthanide(III) ions are in eight‐coordinate environments forming distorted bicapped trigonal prisms. In 1 – 3 , three‐dimensional supramolecular networks of the anions and cations are formed by N–H ··· Se and N–H ··· O hydrogen bonds. To the best of our knowledge, 1 – 3 are the first examples of selenidogermanate salts with lanthanide complex counter cations. 相似文献
999.
Anzheng Hu Haina Li Zhiyong Jia Zhengcai Xia 《Journal of solid state chemistry》2011,184(11):2936-2940
A large clearance TiO2 nanotube arrays (LTAs) has been synthesized by a not more than 12 h anodization duration and based on this a branched TiO2 nanotube arrays (BLTs) has been achieved through TiO2 nanorods branch-like grown on the LTAs. Some key factors and probable mechanisms of the fabrication processes on two novel nanoarchitectures are discussed. Exhilaratingly, it is found that the obtained LTAs has demonstrated large pore diameter and void spaces (pore diameter ∼350 nm; void spaces ∼160 nm; and tube length ∼3.5 μm), and the synthesized hierarchical BLTs, compared with conventional TiO2 nanotube arrays, has shown a much stronger dye absorption performance and an approximately double of the solar cell efficiency (in our case from 1.62% to 3.18% under simulated AM 1.5 conditions). 相似文献
1000.
Poly(Acrylic Acid-b-Styrene) Amphiphilic Multiblock Copolymers as Building Blocks for the Assembly of Discrete Nanoparticles 总被引:1,自引:0,他引:1
In order to expand the utility of current polymeric micellar systems, we have developed amphiphilic multiblock copolymers containing alternating blocks of poly(acrylic acid) and poly(styrene). Heterotelechelic poly(tert-butyl acrylate-b-styrene) diblock copolymers containing an α-alkyne and an ω-azide were synthesized by atom transfer radical polymerization (ATRP), allowing control over the molecular weight while maintaining narrow polydispersity indices. The multiblock copolymers were constructed by copper-catalyzed azide-alkyne cycloaddition of azide-alkyne end functional diblock copolymers which were then characterized by (1)H NMR, FT-IR and SEC. The tert-butyl moieties of the poly(tert-butyl acrylate-b-styrene) multiblock copolymers were easily removed to form the poly(acrylic acid-b-styrene) multiblock copolymer ((PAA-PS)(9)), which contained up to 9 diblock repeats. The amphiphilic multiblock (PAA-PS)(9) (M(n) = 73.3 kg/mol) was self-assembled by dissolution into tetrahydrofuran and extensive dialysis against deionized water for 4 days. The critical micelle concentration (CMC) for (PAA-PS)(9) was determined by fluorescence spectroscopy using pyrene as a fluorescent probe and was found to be very low at 2 × 10(-4) mg/mL. The (PAA-PS)(9) multiblock was also analyzed by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The hydrodynamic diameter of the particles was found to be 11 nm. Discrete spherical particles were observed by TEM with an average particle diameter of 14 nm. The poly(acrylic acid) periphery of the spherical particles should allow for future conjugation of biomolecules. 相似文献