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831.
Ş. Hakan Üngören Mustafa Saçmacı Cengiz Arıcı Ertan Şahin Taner Arslan Fatma Kandemirli 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2877-2890
Novel alkyl substituted 3-(4-benzoyl-1,5-diphenyl-2,3-dihydro-1H-pyrazol-3-yl)-3-oxo-2-(triphenylphosphoranylidene) propanoates (3) were synthesized from 4-benzoyl-1,5-diphenyl-1H-pyrazole-3-carbonylchloride (1) and alkyl (triphenylphosphoranylidene) acetates (2a–b). The synthesized compounds were characterized by elemental analysis, spectroscopic studies (3a–b), and single crystal X-ray diffraction (3a). The mechanism of the reaction between (1) and (2a) was studied by AM1, and the geometrical parameters of the studied molecules were also carried out in B3LYP methods with the standard 6–31G (d,p) basis set. NBO analysis were studied for 1 and 2a B3LYP methods with the standard 6–31G (d,p) basis set. 相似文献
832.
In this study, the mechanical properties and non‐isothermal degradation kinetics of polypropylene (PP), high‐density polyethylene (HDPE) with dilauroyl peroxide and their blends in different mixture ratios were investigated. The effects of adding dilauroyl peroxide (0–0.20 wt%) on the mechanical and thermal properties of PP + HDPE blends have been studied. On the other hand, the kinetics of the thermal degradation and thermal oxidative degradation of PP + HDPE (80/20 wt%) blends were studied in different atmospheres, to analyze their thermal stability. The kinetic and thermodynamic parameters such as the activation energy, Ea, the pre‐exponential factor, A, the reaction order, n, the entropy change, the enthalpy change, and the free energies of activated complex related to PP, HDPE, and blend systems were calculated by means of the several methods on the basis of the single heating rate. A computer program was developed for automatically processing the data to estimate the reaction parameters by using different models. Most appropriate method was determined for each decomposition step according to the least‐squares linear regression. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
833.
We introduce briefly surface modification of clay minerals, structure, properties and, characterization techniques of polymer-clay (PCN's) nanocomposites. Organically modified layered-silicates or nanoclays have become an attractive class of hybrid materials due to their prospective use in a great variety of applications from industry to health. For design, synthesis and characterization for potential biomedical nanocomposites, antitumor-active copolymer; poly(DHP-alt-MA) were used to prepare copolymer/clay nanocomposites. The functional copolymers, having a combination of rigid/flexible linkages and an ability of complex-formation with interlayered surface of organo-silicate, and their nanocomposites have been synthesized by interlamellar complex-radical copolymerization of intercalated monomer complexes of maleic anhydride (MA) and 3,4-Dihydro-2H-pyran (DHP) with three alkyl ammonium salts surface modified bentonite and monomer mixtures. Poly(DHP-alt-MA) pristine copolymer and poly(DHP-alt-MA)/organically modified bentonite nanocomposites were characterized by Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR), HR-Raman, X-ray diffraction (XRD) and TEM methods. 相似文献
834.
ω‐Isonitrosoacetophenone 1, phenylglyoxime 2, chlorophenylglyoxime 1, dopaminophenylglyoxime 3 and [(salen/saloph)Fe]2O 4 have been synthesized as described in the literature procedure. [Fe(III)(salen/saloph)dopaminophenylglyoxime)] (starting complexes) have been synthesized from dopaminophenylglyoxime and tetradentate schiff bases which contain dinuclear Fe(III) oxygen‐bridges N,N′‐bis(salicylidene)ethylenediamine (salenH2) and bis(salicylidene)‐o‐phenylenediamine (salophH2). The new heterotrinuclear complexes have been obtained from starting complexes and Co(II), Ni(II), Cu(II) salts. Then, heterotrinuclear vic‐dioxime complexes containing BF2 + capped have been synthesized. The complexes have been characterized as low‐spin distorted octahedral Fe(III) bridged by o‐hydroxyphenolic groups. The o‐hydroxyphenolic groups play a role as bridges for weak antiferromagnetic intramolecular exchange. The structure of dioxime and its complexes were identified by using elemental analysis, ICP‐AES, 1H‐NMR and IR spectral data. 相似文献
835.
N. Büyükkιdan C. Yenikaya H. İlkimen C. Karahan C. Darcan E. Şahin 《Russian Journal of Coordination Chemistry》2013,39(1):96-103
A novel proton transfer compound (H2Ppz)(HDipic)2 (I) obtained from 2-(piperazin-1-yl)ethanol (Ppz) and pyridine-2,6-dicarboxylic acid (H2Dipic) and its Cu(II) complex (H2Ppz)[Cu(Dipic)2] · 6H2O (II) have been prepared and characterized by elemental, spectral (1H and 13C NMR, IR and Uv-Vis) and thermal analyses. Magnetic measurement and single crystal X-ray diffraction methods have also been applied for compound II. The molecular structure of II consists of one 1-(2-hydroxyethyl)piperazine-1,4-diium cation, one bis(pyridinium-2,6-dicarboxylate)Cu(II) anion and six uncoordinated water molecules. In complex II, the copper ion coordinates to two oxygen and one nitrogen atoms of two pyridine-2,6-dicarboxylate molecules forming an octahedral conformation. Furthermore, the synthesised compounds (I and II) were screened for their antimicrobial activities against Gram (?) (Escherichia coli and Pseudomonas aeruginosa) and Gram (+) (Staphylococcusaureus and Bacillus cereus). The results were reported, discussed and compared with the corresponding starting materials (H2Dipic and Ppz). 相似文献
836.
Sultan Şahin Fatih Külahcı Mahmut Doğru 《Journal of Radioanalytical and Nuclear Chemistry》2011,290(2):313-318
In this study, 90Sr (540 keVβ −), 129I (150 keVβ −) and the gross beta radioactivity concentrations were determined for the samples of tea as the most leading consumed hot
drink in the markets (processed and packaged for sale) in our country. Furthermore, the obtained data were statistically analyzed.
For determination of 129I (150 keVβ−), 90Sr (540 keVβ−) and gross radioactivity concentrations in tea samples, a sensor system consisting of scintillation detector with BP4 probe
sensitive to beta radiation and a radiation meter (ST7) configurable for windows at desired power was used. 相似文献
837.
In this study, flow injection-cloud point extraction (FI-CPE) of iron and copper in food samples by flame atomic absorption spectrometric determination was described. Triton X-114 non-ionic surfactant and Eriochrome Cyanine R (ECR) have been used as an extraction medium and a chelating agent, respectively. The amounts of Triton X-114, ECR and the pH value necessary for extraction were carefully optimized. In addition, several parameters of the FI-CPE system, including sample loading rate, column dimension, type of packing material, eluent flow rate were investigated and analytical characteristics of the method were evaluated. Under optimum conditions, detection limits of 0.33 ng/mL and 0.57 ng/mL and quantification limits of 1.1 ng/mL and 1.9 ng/mL for iron and copper along with enrichment factors of 141 and 99 were obtained, respectively. The calibration was linear over the range 1.5-25 ng/mL and 1.0-35 ng/mL for iron and copper, respectively. The proposed CPE technique has been successfully applied for the determination of iron and copper ions in certified reference materials (NCS DC 73349—bush, branches and leaves; and TM-23.2—fortified water), water samples (mineral and sea water) and food samples (vegetables, bread and hazelnut) with high efficiency. 相似文献
838.
Murat Aydemir Nermin Meric Bahattin Gümgüm Ertan ?ahin 《Journal of organometallic chemistry》2011,696(13):2584-2588
Reaction of Ph2PNHCH2-C4H3S with [Ru(η6-p-cymene)(μ-Cl)Cl]2, [Ru(η6-benzene)(μ-Cl)Cl]2, [Rh(μ-Cl)(cod)]2 and [Ir(η5-C5Me5)(μ-Cl)Cl]2 yields complexes [Ru(Ph2PNHCH2-C4H3S)(η6-p-cymene)Cl2], 1, [Ru(Ph2PNHCH2-C4H3S)(η6-benzene)Cl2], 2, [Rh(Ph2PNHCH2-C4H3S)(cod)Cl], 3 and [Ir(Ph2PNHCH2-C4H3S)(η5-C5Me5)Cl2], 4, respectively. All complexes were isolated from the reaction solution and fully characterized by analytical and spectroscopic methods. The structure of [Ru(Ph2PNHCH2-C4H3S)(η6-benzene)Cl2], 2 was also determined by single crystal X-ray diffraction. 1-4 are suitable precursors forming highly active catalyst in the transfer hydrogenation of a variety of simple ketones. Notably, the catalysts obtained by using the ruthenium complexes [Ru(Ph2PNHCH2-C4H3S)(η6-p-cymene)Cl2], 1 and [Ru(Ph2PNHCH2-C4H3S)(η6-benzene)Cl2], 2 are much more active in the transfer hydrogenation converting the carbonyls to the corresponding alcohols in 98-99% yields (TOF ≤ 200 h−1) in comparison to analogous rhodium and iridium complexes. 相似文献
839.
Design of different type of transducers to enhance image quality by forming narrow beams at the principals of nonlinear acoustics
is considered in the paper. Thus, the nonlinear pressure fields of elliptical and rhomboid transducers were simulated in three
dimensions. The simulation method presented in this study is based on Aanonsen’s model for circular sources, and closely follows
the model that recently explored for the nonlinear wave propagation due to square and rectangular sources in three dimensions
[Kaya et al. “Pressure field of rectangular transducers at finite amplitude in three dimensions,” Ultrasound in Med. Biol.,
vol. 32, no. 2, pp. 271–280, 2006]. It is assumed that elliptical and rhomboid sources are plane sources, and driven at 2.25
MHz fundamental frequency. Typical results of nonlinear acoustical pressure field simulation are presented there in three
dimensions for elliptical and rhomboid sources and compared with the results for rectangular source. The similarities and
differences between the nonlinear pressure field of rectangular, elliptical and rhomboid sources are discussed. The numerical
results show that diffraction effects and acoustical beam cross section depend on the source geometry a lot. It is noticeable
that the nonlinear pressure field of a rectangular source has a broader beam profile than elliptical and rhomboid source. 相似文献
840.
In this paper, the graybody radiation phenomena has been handled with the help of fractional calculus. Fractional definition of graybody spectrum has been written in terms of Mittag‐Leffler function. The obtained data from fractional calculus approximation for nearly 2.87 × 107 K have been compared with literature values and standard blackbody radiation. 相似文献