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181.
An efficient synthesis of thiophene derivatives is described via one-pot reaction between ammonium thiocyanate, acyl chlorides,
α-halocarbonyls, and enaminones under solvent-free conditions at 65 °C. The mild reaction conditions and high yields of the
products exhibit the good synthetic advantage of these methods. 相似文献
182.
183.
Mahdi Farahipour Hossein Fakhraian Akbar Mirzaei Morteza Ali Hosseini 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2303-2310
Abstract L-Gel is an effective decontamination reagent against chemical and biological warfare agents. To achieve optimized formulation of L-Gel, several formulations with different proportional amounts of oxone (oxidizer) and Cab-O-Sil (gelling agent) were prepared and their viscosities and densities were measured. Final optimized formulation of gel was obtained as a 0.25 M aqueous solution of oxone gelled with 13%W/W of Cab-O-Sil EH-5. The L-Gel active ingredient (oxone) was tested against O,O,S-triethyl phosphorothioate (TEPT) as VX simulant and methyl phenyl sulfide (MPS) and chloroethyl phenyl sulfide (CEPS) as HD simulants. Decontamination of TEPT by a 10-fold excess amount of oxone was completed within 7.5 min with a kinetic rate constant of 0.097 S?1. In the presence of oxone, MPS was converted to methyl phenyl sulfoxide and methyl phenyl sulfone with a higher reaction rate than CEPS, decontaminated product of which was chloroethyl phenyl sulfone. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. GRAPHICAL ABSTRACT 相似文献
184.
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186.
Ayoob Bazgir Mozhdeh Seyyedhamzeh Zahra Yasaei Peiman Mirzaei 《Tetrahedron letters》2007,48(50):8790-8794
An efficient synthesis of triazolo[1,2-a]indazole-1,3,8-trione derivatives based on the three-component condensation of urazole, dimedone and aromatic aldehydes under solvent-free conditions is described. 相似文献
187.
Masoud Mirzaei Hossein Eshtiagh‐Hosseini Zahra Karrabi Behrouz Notash 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(10):1140-1143
4‐Hydroxypyridine‐2,6‐dicarboxylic acid (chelidamic acid, hypydc[H]H2) reacts with MnCl2·2H2O in the presence of piperazine in water to afford the title complex, {[Mn3(C7H2NO5)2(H2O)8]·3H2O}n or {[Mn3(hypydc)2(H2O)8]·3H2O}n. This compound is a one‐dimensional coordination polymer, with the twofold symmetric repeat unit containing three metal centres. Two different coordination geometries are observed for the two independent MnII metal centres, viz. a distorted pentagonal bipyramid and a distorted octahedron. The 4‐oxidopyridine‐2,6‐dicarboxylate anions and two of the water molecules act as bridging ligands. The zigzag‐like geometry of the coordination polymer is stabilized by hydrogen bonds. O—H...O and C—H...O hydrogen bonds and water clusters consolidate the three‐dimensional network structure. 相似文献
188.
Mohammadreza Mohammadi Nilash Sajad Avar Fahimeh Mirzaei Ali Reza Fakhari Abbas Rezaee Shirin‐abadi 《Journal of separation science》2020,43(5):920-928
The present study deals with the synthesis and electrospining of a new terpolymer nanofiber in order to determine the amount of diazinon and chlorpyrifos in water and fruit juice samples. The synthesized terpolymer and the prepared nanofiber were characterized using 1H NMR spectroscopy, FTIR spectroscopy, scanning electron microscopy, and gel permeation chromatography. The performance of terpolymer nanofiber, prepared as a sorbent for micro solid phase extraction was investigated for the extraction of diazinon and chlorpyrifos from aquaeous media. Then, the target analytes were desorbed from the coating with an organic solvent and analyzed by gas chromatography with flame ionization detector. Extraction efficiencies were significant (>90%) under the optimum condition. The proposed method also demonstrated good linear dynamic ranges for diazinon and chlorpyrifos (3–250 and 5–200 µg/L), and low limit of detections (0.5 and 0.7 µg/L) respectively. Moreover, under optimum condition for extraction of diazinon and chlorpyrifos, square of correlation coefficients (R2) of 0.9978 and 0.9953 and relative standard deviations of 4.6 and 5.1% were achieved, respectively. The recoveries for diazinon and chlorpyrifos were in the range of 85–97%. 相似文献
189.
Maryam Arsalanfar Mahdi Fatemi Nima Mirzaei Majid Abdouss Esmaeil Rezazadeh 《中国化学会会志》2020,67(7):1152-1166
An investigation of the kinetic and mechanism of CO hydrogenation reaction was performed on impregnated Co-Ni/Al2O3. Determination of kinetic parameters from the experiments was carried out in a micro fixed-bed reactor. Kinetic evaluations were performed under various operational conditions of T = 473–673 K, p = 1–14 bar, H2/CO = 1–3, and GHSV = 4,500 hr−1. Kinetic models and rate equations for CO consumption were obtained by using two main-type rate equations of Langmuir-Hinshelwood-Hougen-Watson (LHHW) and Eley-Rideal (ER). Estimation of various kinetic parameters was performed using a nonlinear regression method. According to the obtained experimental results and using statistical criteria, one kinetic expression based on the LHHW mechanism (-rCO = kp.bCO.PCO. bH2. PH2/[1+ bCO.PCO + bH2.PH2]2) was chosen as the best-fitted model. For this fitted model, the activation energy was found to be 109.2 kJ/mol. Characterization of the catalyst was also performed using X-ray diffraction (XRD), BET, scanning electron microscopy (SEM), and energy-dispersive x-ray spectrometer (EDS) techniques. 相似文献
190.
H. Eshtiagh-Hosseini S. A. Beyramabadi M. Mirzaei A. Morsali A. R. Salimi M. A. Naseri 《Journal of Structural Chemistry》2013,54(6):1063-1069
In this work, a 3,3′-dihydroxy-4,4′-[1,2-cyclohexanediyl-bis(nitrilomethylidyne)]-bis-phenol [=H2L] Schiff-base ligand and its Mn(II) complex [Mn(L)(H2O)2] are newly synthesized and characterized by elemental analysis, IR and NMR spectroscopies. Also the geometry optimizations, assignment of the IR bands and NMR chemical shifts are computed using the density functional theory (DFT) method. The DFT optimized geometry of the ligand is not planar; each of the cyclohexane and two benzene rings are located in separate planes. The phenolic protons are engaged in the intramolecular-hydrogen-bonding interactions with azomethine nitrogen atoms. In the optimized geometry of the octahedral Mn2+ complex, the dianionic L2? acts as a tetradentate ligand in the N, N, O?, O? manner, where the coordinating atoms occupy the four equatorial positions. The two axial positions are occupied by two H2O ligands. The theoretical and experimental results are in good agreement, confirming the validity of the optimized geometries for the H2L ligand and its Mn complex. 相似文献