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201.
Mehrdad Pourayoubi Atekeh Tarahhomi Fatemeh Karimi Ahmadabad Karla Fejfarová Arie van der Lee Michal Dušek 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(4):o164-o169
In N,N′‐di‐tert‐butyl‐N′′,N′′‐dimethylphosphoric triamide, C10H26N3OP, (I), and N,N′,N′′,N′′′‐tetra‐tert‐butoxybis(phosphonic diamide), C16H40N4O3P2, (II), the extended structures are mediated by P(O)...(H—N)2 interactions. The asymmetric unit of (I) consists of six independent molecules which aggregate through P(O)...(H—N)2 hydrogen bonds, giving R21(6) loops and forming two independent chains parallel to the a axis. Of the 12 independent tert‐butyl groups, five are disordered over two different positions with occupancies ranging from to . In the structure of (II), the asymmetric unit contains one molecule. P(O)...(H—N)2 hydrogen bonds give S(6) and R22(8) rings, and the molecules form extended chains parallel to the c axis. The structures of (I) and (II), along with similar structures having (N)P(O)(NH)2 and (NH)2P(O)(O)P(O)(NH)2 skeletons extracted from the Cambridge Structural Database, are used to compare hydrogen‐bond patterns in these families of phosphoramidates. The strengths of P(O)[...H—N]x (x = 1, 2 or 3) hydrogen bonds are also analysed, using these compounds and previously reported structures with (N)2P(O)(NH) and P(O)(NH)3 fragments. 相似文献
202.
Majedi FS Hasani-Sadrabadi MM Emami SH Taghipoor M Dashtimoghadam E Bertsch A Moaddel H Renaud P 《Chemical communications (Cambridge, England)》2012,48(62):7744-7746
A microfluidic platform is developed for the synthesis of monodisperse, 100 nm, chitosan based nanoparticles using nanogelation with ATP. The resulting nanoparticles tuned and enhanced transport and electrochemical properties of Nafion based nanocomposite membranes, which is highly favorable for fuel cell applications. 相似文献
203.
204.
Mohammad Navid Soltani Rad Somayeh Behrouz Fatemeh Karimitabar Ali Khalafi‐Nezhad 《Helvetica chimica acta》2012,95(3):491-501
The ‘click synthesis’ of some novel O‐substituted oximes, 7a – 7t , which contain 1,2,3‐triazolediyl residues, as new analogs of β‐adrenoceptor antagonists is described (Schemes 1–4). The synthesis of these compounds was achieved in four to five steps. The formation of oximes of 9H‐fluoren‐9‐one and benzophenone, i.e., 9a and 9b , respectively, followed by their reaction with propargyl bromide, afforded O‐propargyl oximes 10a and 10b , respectively, which by a subsequent CuI‐catalyzed Huisgen cycloaddition with prepared β‐azido alcohols 11a – 11j (Schemes 2 and 3), led to the target compounds 7a – 7t in good yields. 相似文献
205.
S. Masoud Nabavizadeh Hashem Amini Fatemeh Jame Sedigheh Khosraviolya Hamid R. Shahsavari Fatemeh Niroomand Hosseini Mehdi Rashidi 《Journal of organometallic chemistry》2012
New cyclometalated platinum(II) complexes [PtMe(C^N)L], 1, in which C^N = deprotonated 2-phenylpyridine (ppy), benzo[h]quinoline (bhq) or 2-(p-tolyl)pyridine (tpy) and L = PPh3 or PMePh2, were synthesized by the reaction of [PtMe(C^N)(SMe2)] with 1 equiv of L. The reaction of complexes 1 with MeI gave the cyclometalated Pt(IV) complexes [PtMe2I(C^N)L], 3. On the basis of kinetic studies, using Uv–visible spectroscopy, it was suggested that the latter oxidative addition reactions were proceeded by an SN2 mechanism. The rates of the reactions at different temperatures were measured and consistent with the proposed mechanism, large negative ΔS3 values were found for each reaction. Besides, rate of reactions (in CHCl3) involving the PPh3 complexes [PtMe(C^N)(PPh3)], were almost 3–5 times slower than those involving the PMePh2 complexes [PtMe(C^N)(PMePh2)]. This was attributed to the electronic and steric effects of PPh3 ligand as compared with that of PMePh2 ligand which was further confirmed using density functional theory (DFT) calculations through finding approximate structures for the described complexes. 相似文献
206.
Amir Rineh Mohammad A. Khalilzadeh Mohammad M. Hashemi Medí Rajabi Fatemeh Karimi 《Journal of heterocyclic chemistry》2012,49(4):789-791
An efficient synthesis of quinoline derivatives is described via the reaction between ethyl chloropyruvate or alkyl 4‐chloroacetoacetate and activated acetylenic compounds in the presence of nucleophilic form of isatin in water as the solvent. Nucleophilic form of isatin is produced from the reaction of isatin and triethylamin. 相似文献
207.
The activity of palladacycle [Pd{C6H4(CH2N(CH2Ph)2)} (μ-Br)]2 complex was investigated in the synthesis of benzonitriles under both conventional and microwave irradiation conditions and their results were compared together. This complex is an efficient, stable, and non-sensitive to air and moisture catalyst for the cyanation reaction. The substituted benzonitriles were produced of various aryl halides in excellent yields and short reaction times using a catalytic amount of [Pd{C6H4(CH2N(CH2Ph)2)} (μ-Br)]2 complex and K4[Fe(CN)6] in DMF at 130 °C. In comparison to conventional heating conditions, the reactions under microwave irradiation gave higher yields in shorter reaction times. 相似文献
208.
Issa Yavari Manijeh Nematpour Sima Yavari Fatemeh Sadeghizadeh 《Tetrahedron letters》2012,53(15):1889-1890
Ketenimine intermediates generated by the addition of copper acetylides to sulfonyl azides are trapped by nitrile imines (generated from hydrazonoyl chlorides and triethylamine) to afford tetrasubstituted pyrazoles in moderate to good yields. 相似文献
209.
One of the applications of nanotechnology is use of carbon nanotubes for the targeted delivery of drug molecules. To demonstrate the physical and chemical properties of biomolecules and identify new material of drug properties, the interaction of carbon nanotubes (CNTs) with biomolecules is a subject of many investigations. CNTs is a synthetic compound with extraordinary mechanical, thermal, electrical, optical, and chemical properties widely applied for technological purposes. In this article we have tried to investigate thermodynamic parameters and dielectric effects in different solvents for one of the most famous anticancer drug ??cisplatin?? combined to SWCNT, by Monte Carlo and density functional theory (DFT) calculations. Cause of platinum element in cisplatin we have done calculations as Gibbs free energy, thermal enthalpy, thermal energy and entropy at 6-31G** basis set with SCRF model of solvent. In this work, the major point has been embedded that results of both two methods of Monte Carlo and DFT can overlap with each other and cisplatin- SWCNT is a suitable compound for drug delivery in different media. 相似文献
210.
Khodayar Gholivand Nilufar Dorosti Fatemeh Ghaziany Manouchehr Mirshahi Sina Sarikhani 《Heteroatom Chemistry》2012,23(1):74-83
A new series of N‐phosphinylureas 5b, 6a–7c was synthesized and characterized by 1H, 13C, 31P NMR, IR, and elemental analysis. The three‐dimensional structure of 5b has been determined by X‐ray crystallography. The crystal structure revealed the existence of four independent molecules. All structures form two chains with different arrangements and connect to each other via hydrogen bonds to produce two‐dimensional polymeric chains. The cytotoxicity of cyclophosphamide (a standard antitumor compound) and its nine analogues with formula R1C6H4 NHC(O)NHP(O)XCH2C(R2)2 CH2Y(X = Y = NH, R2 = CH3, R1 = H ( 5a ), CH3 ( 5b ), NO2 ( 5c ), X = O, Y = NH, R2 = H, R1 = H ( 6a , CH3 ( 6b ), NO2 ( 6c ), and X = Y = O, R2 = CH3, R1 = H ( 7a ), CH3 ( 7b ), NO2 ( 7c )) as well as phenyl urea were evaluated in vitro against three human tumor cell lines K562, MDA‐MB‐231, and HepG2. The results showed that most of the compounds have significant activity against the selected cell lines. Also, HepG2 cells were more sensitive to all the tested compounds than other cell lines. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 23:74–83, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20754 相似文献