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991.
Synthesis and photochromic behavior of mono-, and biphotochromic system linked by p-phenylene bridge
<正>The synthesis of mono- and bis-l,3-diazabicyclo[3.1.0]hex-3-ene derivatives with indole ring and p-phenylene spacer,which behave as photochromic materials,is reported.The structure-photochromic behavior relationship(SPBR) of the synthesized compounds has been analyzed. 相似文献
992.
Majid M. Heravi Ladan Sangsefidi Hossein A. Oskooie Mitra Ghassemzadeh Koroush Tabar-Hydar 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):707-709
Adsorbed on silica gel. Dess-Martin periodinane can rapidly oxidize alcohols to the corresponding carbonyl compounds upon exposure to microwave under solvent-free condition. 相似文献
993.
Hassan Valizadeh F. Mahmoodi Kordi Hamid Gholipur Mohammad Amiri 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):3075-3081
Phosphoric acid imidazolium dihydrogenphosphate was found to work well as a catalyst and excellent reaction medium in the Pechmann condensation of substituted phenols or α-naphthol with ethyl acetoacetate to give 4-methyl coumarins under microwave irradiation. This method is simple, cost effective, requires short reaction times, and gives very good to excellent yields. 相似文献
994.
Ozlem Demirkiran Gülaçtı Topçu Fatemeh Bahadori Mehmet Ay Hossein Nazemiyeh Iqbal Choudhary 《Helvetica chimica acta》2010,93(1):77-83
Two new phenylpropanoid glucosides, 1,2‐erythro‐1‐(3,4,5‐trimethoxyphenyl)‐2‐(β‐D ‐glucopyranosyloxy)propan‐1,3‐diol ( 1 ) and 7,8‐threo‐2′,8‐epoxysyringylglycerol‐7‐O‐α‐D ‐glucopyranoside (ericarboside; 2 ) have been isolated together with four known compounds 2′,7‐epoxysyringylglycerol‐8‐O‐β‐D ‐glucopyranoside (ficuscarpanoside B; 3 ), benzylrutinoside (hydrangeifolin; 4 ), phenethylrutinoside ( 5 ), and caffeic acid from the BuOH soluble part of the MeOH extract of the leaves and flowers of E. arborea L. Final purification of the compounds was achieved on a reversed‐phase HPLC. Their structures have been elucidated by extensive 1D‐ and 2D‐NMR, and mass spectroscopic techniques. 相似文献
995.
Hossein Naeimi 《中国化学会会志》2008,55(5):1156-1159
The highly regioselective cleavage of epoxides into corresponding vicinal haloalcohols with elemental halogen has been catalyzed by hexamethylenetetramine (HMTA). This method occurred under neutral and mild conditions with high yields and short reaction times in various aprotic solvents even when sensitive functional groups were present. 相似文献
996.
Biuck Habibi Mojtaba Jahanbakhshi Mohammad Hossein Pournaghi-Azar 《Mikrochimica acta》2012,177(1-2):185-193
A nanohybrid composite material was prepared from single-walled carbon nanotubes and silver nanoparticles, and used to fabricate a modified carbon-ceramic electrode. The preparation of the composite is facile and efficient. The nanohybrid composite deposited on the carbon-ceramic electrode was characterized by X-ray diffraction and cyclic voltammetry. The new electrode displays favorable electrocatalytic ability towards hydrogen peroxide (H2O2) and can be used to electrocatalytically reduce this species. Under the optimum conditions, the current measured during hydrodynamic amperometry is linearly related to the concentration of H2O2 over the concentration range from 0.01 to 8 mM, with a detection limit of 2?×?10?7 M at a signal-to-noise ratio of 3 and sensitivity of 3.23 μA/mM. The electrode exhibits good reproducibility, long-term stability and negligible interference by dopamine, uric acid, and other important biological compounds. The electrode was successfully applied to the determination of H2O2 in honey samples, and the recovery was 101.2%. Figure
CVs of bare CCE (a, a′) and SWCNT (b, b′) and SWCNT/AgNPs (c, c′) modified electrodes in phosphate buffer solution (0.1 M, pH 7.0) without and with 5 mM H2O2, respectively. Scan rate is 50 mVs?1. 相似文献
997.
Mahdi?SadeghiEmail author Nadia?Zandi Hossein?Afarideh 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(3):731-738
In recent years, there has been a rapid expansion in the use of radio nuclides for therapeutic purposes. Thulium–167 is an
important radionuclide (T
1/2 = 9.25 d) due to it could be used for tumor and bone studies in nuclear medicine. 167Tm complexed with hydroxy ethylene diamine tetra-acetic acid (HEDTA) could be used with the aim of bone imaging. 167Tm emits a prominent γ ray of 208 keV energy and low energy electrons. This study describes calculations on the excitation
functions of 165Ho(α,2n)167Tm, 167Er(p,n)167Tm, natEr(d,xn)167Tm and natEr(p,xn)167Tm reactions by ALICE/ASH (hybrid and GDH models) and TALYS-1.0 codes. In addition, calculated data by codes were compared
to experimental data that earlier were published and TENDL-2010 database. Moreover, optimal thickness of the targets and physical
yield were obtained by SRIM (stopping and range of ions in matter) code for each reaction. According to the results, the 167Er(p,n)167Tm and 165Ho(α,2n)167Tm reactions are suggested as the best method to produce 167Tm owing to minimum impurities. The TALYS-1.0 code, predict the maximum cross-section of about 382 mb at 11 MeV and 849 mb
at 26 MeV for 167Er(p,n)167Tm and 165Ho(α,2n)167Tm reactions, respectively. Finally, deposition of natEr2O3 on Cu substrate was carried out via the sedimentation method. The 516 mg of erbium(III)oxide with 103.2 mg of ethyl cellulose
and 8 mL of acetone were used to prepare a natEr2O3 layer of 11.69 cm2. 167Tm was produced via the natEr(p,n)167Tm nuclear process at 20 μA current and 15 → 7 MeV protons beam (1 h). Yield of about 3.2 MBq 167Tm per μA h were experimentally obtained. 相似文献
998.
Sayed Mehdi Ghoreishi Mohsen Behpour Samaneh Mazaheri Hossein Naeimi 《Journal of Radioanalytical and Nuclear Chemistry》2012,293(1):201-210
The electrochemical determination of uranyl was investigated by using carbon paste electrode modified with a Schiff base namely N,N??-bis(salicylidene)-2-hydroxy-phenylmethanediamine (SHPMD/CPE) and also in the presence of carbon nanotube (SHPMD/CNT/CPE). The both modified electrodes displayed an irreversible peak at E pa?=?0.798?V versus Ag/AgCl. The electrocatalytic reduction of uranyl has been studied on SHPMD/CNT/CPE, using cyclic and differential pulse voltammetry, chronocoulometry and linear sweep techniques. Electrochemical parameters including the diffusion coefficient (D), the electron transfer coefficient (??), the ionic exchange current (i) and the redox reaction rate constant (K) were determined for the reduction of uranyl on the surface of the modified electrodes. Linear range concentration is 0.002?C0.6???mol?L?1 and the detection limit of uranyl is 0.206?nmol?L?1. The proposed method was used to detect uranyl in natural waters and good recovery was achieved. 相似文献
999.
Gholam Hossein Rounaghi Behjat Deiminiat 《Journal of inclusion phenomena and macrocyclic chemistry》2012,72(1-2):113-119
The complexation reaction between Y3+ cation with N-phenylaza-15-crown-5(Ph-N15C5) was studied at different temperatures in acetonitrile–methanol (AN/MeOH), acetonitrile–propanol (AN/PrOH), acetonitrile–1,2 dichloroethane (AN/DCE) and acetonitrile–water (AN/H2O) binary mixtures using the conductometric method. The results show that in all cases, the stoichiometry of the complex is 1:1 (ML). The values of formation constant of the complex which were determined using conductometric data, show that the stability of (Ph-N15C5.Y)3+ complex in pure solvents at 25?°C changes in the following order: PrOH?>?AN?>?MeOH and in the case of binary mixed solutions at 25?°C it follows the order: AN–DCE?>?AN–PrOH?>?AN–MeOH?>?AN–H2O. The values of standard thermodynamic quantities (?H c ° and ?S c ° ) for formation of (Ph-N15C5.Y)3+ complex were obtained from temperature dependence of the formation constant using the van’t Hoff plots. The results show that in most cases, the complex is entropy and enthalpy stabilized and these parameters are influenced by the nature and composition of the mixed solvents. In most cases, a non-linear behavior was observed for variation of log Kf of the complex versus the composition of the binary mixed solvents. In all cases, an enthalpy–entropy compensation effect was observed for formation of (Ph-N15C5.Y)3+ complex in the binary mixed solvents. 相似文献
1000.
Five organotin(IV) complexes,were obtained by reaction of SnR2Cl2(R = Ph,Me,Bu) with ONO donor Schiff bases.The synthesized complexes have been investigated by elemental analysis and IR,1H NMR,and 119Sn NMR spectroscopy.These data show that the Schiff base acts as a tridentate dianionic ligand and coordinates via the imine nitrogen and two oxygen atoms.The Xray crystallography of complex 4 shows a dimeric structure for this molecule.The in vitro antibacterial activities of the Schiff bases and their complexes have been evaluated against Gram-positive(Bacillus subtilis and Staphylococcus aureus) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria and compared with the standard antibacterial drugs. 相似文献