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991.
《应用有机金属化学》2017,31(9)
Because of the side effects and drug resistance of cisplatin, a basic clinically approved chemotherapeutic drug, a new attempt is reported to develop a novel antitumor drug based on complexation of iron metal ion with organic moiety that may be effective and safer. A newly synthesized iron(III) diacetylmonoxime‐2‐hydrazinopyridine complex was tested firstly for its cytotoxicity and superoxide dismutase (SOD)‐mimic activity in vitro then for its antitumor activity against Ehrlich ascites carcinoma (EAC) and the related biochemical alterations in vivo in comparison with cisplatin. The complex showed 80.88% SOD‐mimic activity and IC50 of 2.6 μg ml−1. In EAC‐bearing mice, in a dose‐dependent manner, Fe(III) complex treatment exhibited significant hematological profile improvements, tumor volume, viable cell count and hepatic lipid peroxidation level decreases, life span extension, hepatic glutathione and total antioxidant capacity levels enhancements, hepatic SOD and catalase activities augmentations, liver function tests alterations attenuations, and hepatocyte nucleic acids content normalization. Thus, the Fe(III) diacetylmonoxime‐2‐hydrazinopyridine complex is a novel, promising, less toxic antitumor agent. Its killing of tumor cells may be via a reactive oxygen species scavenging mechanism. 相似文献
992.
《应用有机金属化学》2017,31(9)
A β‐diketimine ligand with vinylidene substitution at γ‐carbon, CH2C(CH3CNAr)2 (Ar = 2,6‐diisopropylphenyl) ( L 2 ), was synthesized by treating β‐diketimine H2C(CH3CNAr)2 with n ‐BuLi followed by paraformaldehyde. L 2 formed the homobimetallic ether‐bridged β‐diketiminate complex [O{(CH2‐β‐diketiminate)Pd(OAc)}2] ( 1 ) with (PdOAc)2. It also gave complexes [L2PdCl2] ( 2 ) and [L2NiBr2] ( 3 ) when treated with PdCl2(CH3CN)2 and NiBr2(dimethoxyethane), respectively. All the compounds were characterized using 1H/13C NMR spectroscopy and single‐crystal X‐ray diffraction studies. The catalytic activity of Pd and Ni complexes 1 , 2 and 3 was explored in Heck coupling and alkyne trimerization reactions and it was found that they are very good catalysts. The results are reported in detail. 相似文献
993.
《应用有机金属化学》2017,31(11)
In the presence of iron pentacarbonyl, photochemical reaction between phenylisocyanate and ferrocenylacetylene results in ferrapyrrolinone complex [Fe2(CO)6(μ2‐η3‐FcC═C(H)C(O)NPh)] ( 1 ) and maleimide 3‐ferrocenyl‐1‐phenyl‐1H ‐pyrrole‐2,5‐dione ( 2 ). Under similar experimental conditions, ferrocenyl−/phenyl‐substituted butadiyne primarily shows the activation of only one C☰C bond and results in ferrapyrrolinone complexes [Fe2(CO)6(μ2‐η3‐FcC═C(C☰CR)C(O)NPh)] ( 3 , R = Fc; 3a , R = Ph), maleimides 3‐ferrocenyl‐1‐phenyl‐4‐(ferrocenylethynyl)‐1H –pyrrole‐2,5‐dione ( 5 ) and 3‐ferrocenyl‐1‐phenyl‐4‐(phenylethynyl)‐1H –pyrrole‐2,5‐dione ( 5a ) and [Fe2(CO)6(μ2‐η3‐FcC═C(R)C(O)NPh)] ( 4 ; R = 3‐ferrocenyl‐1‐phenyl‐1H ‐pyrrole‐2,5‐dione). Compound 4 consists of ferrapyrrolinone and a maleimide unit, formed by the activation of both C☰C bonds of diferrocenylbutadiyne. Activation of both C☰C bonds in a substituted butadiyne is a rare observation. Formation of the ferrapyrrolinone compounds is an advance over the earlier reported methods which generally use internal alkynes and involve prior synthesis of other clusters. 相似文献
994.
《应用有机金属化学》2017,31(12)
A novel tridentate chelating ligand, Ethyl 2‐(2‐(2‐chlorobenzoyl)hydrazono)propanoate and its late transition metal complexes were synthesized, characterized and evaluated for anticancer behavior. The structures were elucidated with the help of elemental analyses, spectral (vibrational, electronic, NMR and mass) and thermo‐gravimetric techniques. Single crystal X‐ray crystallographic studies of the ligand suggest an orthorhombic lattice structure with Pna21 space group. The interaction of ligand and complexes with DNA (CT‐DNA) has been extensively studied using absorption, emission, viscosity and thermal denaturation studies with E. coli DNA. The DNA cleavage ability of ligand and metal complexes was tested using plasmid pBR322 DNA by gel electrophoresis method. The ligand and its copper complex have been evaluated for their in vitro anticancer activity against human cancer cells of different origin such as KB (Oral), A431 (Skin), Mia‐Pa‐Ca (Pancreases), K‐549 (Lung), K‐562 (Leukemia), MCF‐7 (Breast) and VERO by MTT assay and the apoptosis assay was carried out with acridine orange/ethidium bromide (AO/EB) staining method. The studies suggest that ligand and copper complex exhibit significant cytotoxic activity on KB, MCF‐7, A‐431, Mia‐Pa‐Ca‐2 an d A‐549 cell lines compared to K‐562 and VERO cell lines. 相似文献
995.
A “Mitsubishi emblem” tetrauclear aluminum complex containing two unsymmetric N2O2‐ligands and a symmetric NO3‐ligand as initiator for polymerization of rac‐lactide 下载免费PDF全文
Minggang Hu Fugui Wang Fuzhong Han Qigang Deng Wenhui Ma Hailong Yan Guohua Dong Weiming Song 《Journal of polymer science. Part A, Polymer chemistry》2017,55(12):2084-2091
A novel hydroxy‐, methoxy‐, and phenoxy‐bridge “Mitsubishi emblem” tetranuclear aluminum complex ( 1 ) is synthesized from an unsymmetric amine‐pyridine‐bis(phenol) N2O2‐ligand (H2L1) and a symmetric amine‐tris(phenol) NO3‐ligand (H2L2). Two same configuration chiral nitrogen atoms are formed in the tetranuclear Al complex upon coordination of the unsymmetric tertiary amine ligand to central Al. Complex 1 initiates controlled ring‐opening polymerization (ROP) of rac‐lactide and afford polylactide (PLA) with narrow molecular weight distributions (Mw/Mn = 1.05–1.19). The analysis of 1H NMR spectra of the oligomer indicates that the methoxy group is the initiating group and the ring‐opening polymerization of lactide follows a coordination‐insertion mechanism. The Homonuclear decoupled 1H NMR spectroscopy suggests the isotactic‐rich chains is preferentially formed in PLA. The study on kinetics of the ROP of lactide reveals the homopropagation rate is higher than the cross‐propagation rate, which is in agreement with the observed isotactic selectivity in the ROP of rac‐lactide. The stereochemistry of the polymerization was also supported by activation parameters. The introduction of unsymmetric ligand H2L1 has an effect on stereoslectivity of polymerization. This result may be of interest for the design of multinuclear metal complex catalysts containing functionalized ligands. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2084–2091 相似文献
996.
吴世康 《影像科学与光化学》2017,35(1)
表面等离子共振光谱(Surface Plasmon Resonance,SPR)是近年来得到快速发展的一门技术。它是一种无标记的、可用于实时定量检测某些固定于传感芯片上的组分与被结合物种间的绑定亲合度(binding affinity)、且可用于对相对小量物质进行检测的重要手段。由于它可方便地研究不同生物或化学物种的有关反应与动力学问题,因此具有重要的实用意义,受到广泛关注和重视。本文对有关等离子共振现象的形成及其作为敏感检测手段的机制、原理和改进等问题作了简要的介绍。 相似文献
997.
《化学:亚洲杂志》2017,12(20):2684-2693
Electrostatic interactions are characteristic of ionic liquids (ILs) and play a pivotal role in determining the formation of species when solutes are dissolved in them. The formation of new species/complexes has been investigated for certain ILs. However, such investigations have not yet focused on eutectic liquids, which are a promising class of ILs. These liquids (or liquid coordination complexes, LCCs) are rather new and are composed of cationic and anionic chloro complexes of metals. To date, these liquids have been employed as electrolytes to deposit metals and as solvents for catalysis. The present study deals with a liquid that is prepared by mixing a 1.2:1 mol ratio of AlCl3 and 1‐butylpyrrolidine. An attempt has been made to understand the interactions of FeCl2 with the organic molecule using spectroscopy. It was found that dissolved Fe(II) species interact mainly with the IL anion and such interactions can lead to changes in the cation of the electrolyte. Furthermore, the viability of depositing thick magnetic films of Fe and Fe–Al has been explored. 相似文献
998.
Synthesis and characterization of polymer linked copper(I) bis(N‐heterocyclic carbene) mechanocatalysts 下载免费PDF全文
Philipp Michael Shima Khazraee Sheidaee Mehr Wolfgang H. Binder 《Journal of polymer science. Part A, Polymer chemistry》2017,55(23):3893-3907
In this paper, the synthesis and characterization of a series of latent polymeric bis(N‐heterocyclic carbene) (NHC) copper(I) complexes is reported, which can be activated for the copper(I)‐catalyzed azide/alkyne cycloaddition (CuAAC) via ultrasound. To prove the influence of chain length and nature of the polymer towards the activation, poly(isobutylene) (PIB), poly(styrene) (PS) and poly(tetrahydrofuran) (PTHF) are synthesized via living polymerization techniques (LCCP, ATRP, CROP) obtaining different chain lengths (from 2500 to 9000 g/mol), followed by quaternization with N‐methylimidazole, generating the corresponding N‐methylimidazolium‐telechelic polymers. The deprotonation of these macroligands via strong bases like sodium tert‐butoxide (NaOtBu) or potassium hexamethyldisilazide (KHMDS) yields the free N‐heterocyclic carbenes (NHCs), which are used to coordinate to tetrakis(acetonitrile)copper(I) hexafluorophosphate, forming the final polymer‐based mono‐ and bis(N‐methylimidazole‐2‐ylidene) copper(I)X complexes. The structural proof of these complexes is accomplished via 1H‐NMR spectroscopy, MALDI‐TOF‐MS and GPC‐techniques. The activation of the copper(I) biscarbene catalysts by ultrasound is studied by GPC, revealing the cleavage of one shielding NHC‐ligand. The initial catalytic latency and the via ultrasound introduced catalytic activation is successfully demonstrated monitoring a CuAAC “click” reaction of benzyl azide and phenylacetylene by in situ 1H‐NMR spectroscopy introducing thus “click” conversions up to 97%. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 3893–3907 相似文献
999.
Precise synthesis of a series of poly(4‐n‐alkylstyrene)s and their glass transition temperatures 下载免费PDF全文
Satoru Matsushima Atsushi Takano Yoshiaki Takahashi Yushu Matsushita 《Journal of Polymer Science.Polymer Physics》2017,55(9):757-763
Poly(4‐n‐alkylstyrene)s with six kinds of n‐alkyl groups such as methyl, ethyl, propyl, butyl, hexyl, and octyl groups covering wide molecular weight range from around 5 k to over 100 k were precisely synthesized by living anionic polymerizations. It was confirmed that all the polymers obtained have narrow molecular weight distribution, that is, Mw/Mn is all less than 1.1, by SEC. Tgs of all the polymers were estimated by DSC measurements and it turned out to be clear that their molecular weight dependence was well described by the Fox–Flory equations. Furthermore, it is evident that Tg monotonically decreases as a number of carbon atoms of n‐alkyl group is increased, though Tg values are all 20 K or more higher than those reported previously for the same polymer series. This is because backbone mobility increases by introducing longer n‐alkyl side groups with high mobility, while Tg difference in between this work and the previous one may due to the experimental conditions and also to the molecular weight range adopted. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 757–763 相似文献
1000.
Immobilization of AIEgens into metal‐organic frameworks: Ligand design,emission behavior,and applications 下载免费PDF全文
Bo Gui Na Yu Yi Meng Fang Hu Cheng Wang 《Journal of polymer science. Part A, Polymer chemistry》2017,55(11):1809-1817
Aggregation‐induced emission (AIE), in which the luminophores are highly emissive in aggregate state, is one of the most unique photophysical phenomena and has shown interesting applications in many areas. The immobilization of AIE luminogens (AIEgens) into metal‐organic frameworks (MOFs), which are inorganic‐organic hybrid porous materials with tunable and predictable structures, has been investigated over the past few years. These well‐defined porous frameworks cannot only provide an ideal platform for studying the mechanism of AIE phenomenon in solid state, but also show potential applications from sensing to white light‐emitting diodes. In this highlight, we will summarize the recent progress of AIEgens‐based MOFs, including ligand design, emission behavior, and applications. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 1809–1817 相似文献