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991.
Dr. Samir Kumar Sarkar Dr. Subrata Kundu Dr. Mohd Nazish Johannes Kretsch Dr. Regine Herbst-Irmer Prof. Dietmar Stalke Parameswaran Parvathy Dr. Pattiyil Parameswaran Prof. Herbert W. Roesky 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(31):e202200913
Herein, the synthesis and characterization of the carbene-stabilized boryl phosphinidenes 1 – 3 are reported. Compounds 1 – 3 are obtained by reacting Me-cAAC=PK (Me2-cAAC=dimethyl cyclic(alkyl)(amino)carbene) and dihaloaryl borane in toluene. All three compounds were characterized by X-ray crystallography. Quantum mechanical studies indicated that these compounds have two lone pairs on the P center viz., an σ-type lone pair and a “hidden” π-type lone pair. Hence, these compounds can act as double Lewis bases, and the basicity of the π-type lone pair is higher than the σ-type lone pair. 相似文献
992.
Arunprasad Veeranan Siva Karthik P. Thulasi Selvam Arul G. P. Shkir Mohd. Rajamanickam A. T. Sumathi T. Fredrick Sonia R. 《Journal of Cluster Science》2022,33(6):2651-2659
Journal of Cluster Science - A facile one step synthetic hydrothermal route was used to fabricate the Pt free Ni3S4/CoS2 heterostructure counter electrode and study the photovoltaic characteristics... 相似文献
993.
994.
Mohd A. Khan Ibraheam Al‐Shankiti Ahmed Ziani Nimer Wehbe Hicham Idriss 《Angewandte Chemie (International ed. in English)》2020,59(35):14802-14808
The major challenge in solar water splitting to H2 and O2 is in making a stable and affordable system for large‐scale applications. We have designed, fabricated, and tested a photoelectrochemical reactor characterized as follows: 1) it comprises an integrated device to reduce the balance of the system cost, 2) it utilizes concentrated sunlight to reduce the photoabsorber cost, and 3) it employs and alkaline electrolyte to reduce catalyst cost and eliminate external thermal management needs. The system consists of an III‐V‐based photovoltaic cell integrated with Ni foil as an O2 evolution catalyst that also protects the cell from corrosion. At low light concentration, without the use of optical lenses, the solar‐to‐hydrogen (STH) efficiency was 18.3 %, while at high light concentration (up to 207 suns) with the use of optical lenses, the STH efficiency was 13 %. Catalytic tests conducted for over 100 hours at 100–200 suns showed no sign of degradation nor deviation from product stoichiometry (H2/O2=2). Further tests projected a system stability of years. 相似文献
995.
Rabita Mohd Firdaus Nawal Berrada Alexandre Desforges Abdul Rahman Mohamed Brigitte Vigolo 《化学:亚洲杂志》2020,15(19):2902-2924
The combination of exceptional functionalities offered by 3D graphene‐based macrostructures (GBMs) has attracted tremendous interest. 2D graphene nanosheets have a high chemical stability, high surface area and customizable porosity, which was extensively researched for a variety of applications including CO2 adsorption, water treatment, batteries, sensors, catalysis, etc. Recently, 3D GBMs have been successfully achieved through few approaches, including direct and non‐direct self‐assembly methods. In this review, the possible routes used to prepare both 2D graphene and interconnected 3D GBMs are described and analyzed regarding the involved chemistry of each 2D/3D graphene system. Improvement of the accessible surface of 3D GBMs where the interface exchanges are occurring is of great importance. A better control of the chemical mechanisms involved in the self‐assembly mechanism itself at the nanometer scale is certainly the key for a future research breakthrough regarding 3D GBMs. 相似文献
996.
Mohammed S. M. Saleh Dzatil Awanis Mohd Bukhari Abdul Razak Kasmuri Suganya Murugesu Alfi Khatib 《Natural product research》2020,34(9):1341-1344
AbstractDifferent extraction processes were employed to extract bioactive metabolites from Salacca zalacca flesh by a range of aqueous and organic solvents. The highest extraction yield was obtained by 50% ethanol extract of SE (73.18?±?4.35%), whereas SFE_1 showed the lowest yield (0.42?±?0.08%). All extracts were evaluated for in vitro α-glucosidase inhibitory activity, measured by their IC50 values in comparison to that of quercetin, the positive control (IC50 = 2.7?±?0.7?μg/mL). The lowest α-glucosidase inhibitory activity was indicated by water extract of SE (IC50 = 724.3?±?42.9?μg/mL) and the highest activity was demonstrated by 60% ethanol extract by UAE (IC50 = 16.2?±?2.4?μg/mL). All extracts were analysed by GC-MS and identified metabolites like carbohydrates, fatty acids, organic acids, phenolic acids, sterols and alkane-based compounds etcetera that may possess the potential as α-glucosidase inhibitor and may attribute to the α-glucosidase inhibitory activity. 相似文献
997.
It is known that silver (Ag) nanoparticles are attractive due to their novel and mild chemical and physical properties. In this research, anisotropic mono-dispersed silver nanoparticles are synthesized via a simple chemical reduction method and assisted by Daxad 19 surfactant. The reactant temperatures and weight ratios of the chemical constituents play a key role in controlling the hybrid shaping mechanism. The results indicate that the reduction rate of Ag+ to Ag0 nanoparticles is enhanced significantly with increasing weight ratios of Daxad 19 and AgNO3 under controlled reactant temperature. The results show that the as-prepared silver nanoparticles are well-dispersed and uniform in size and shape. The dimensions of the particles are easily controlled. A comparison between experimental absorbance UV-visible spectra and simulated spectra from Mie's Scattering Theory is carried out. It is observed that the simulated spectrum confirms well with the optical behaviour of the experimental spectra. 相似文献
998.
U. N. Tripathi G. Venubabu Mohd. Safi Ahmad S. S. Rao Kolisetty A. K. Srivastava 《应用有机金属化学》2006,20(10):669-676
Diorganotin(IV) dipyrazolinates of the type R2Sn(C15H12N2OX)2 [where C15H12N2OX = 3(2′‐Hydroxyphenyl)‐5(4‐X‐phenyl)pyrazoline {where X = H ( a ); CH3 ( b ); OCH3 ( c ); Cl ( d ) and R = Me, Prn and Ph}] have been synthesized by the reaction of R2SnCl2 with sodium salt of pyrazolines in 1:2 molar ratio, in anhydrous benzene. These newly synthesized derivatives have been characterized by elemental analysis (C, H, N, Cl and Sn), molecular weight measurement as well as spectral [IR and multinuclear NMR (1H, 13C and 119Sn)] studies. The bidentate behaviour of the pyrazoline ligands was confirmed by IR, 1H and 13C NMR spectral data. A distorted trans‐octahedral structure around tin(IV) atom for R2Sn(C15H12N2OX)2 has been suggested. The free pyrazoline and diorganotin(IV) dipyrazolinates have also been screened for their antibacterial and antifungal activities. Some diorganotin(IV) dipyrazolinates exhibit higher antibacterial and antifungal effect than free ligand and some of the antibiotics. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
999.
Wan Sharifatun Handayani Wan Zullkiplee Maya Asyikin Mohd Ariff Hasnain Hussain Wan M. Khairul 《Phosphorus, sulfur, and silicon and the related elements》2016,191(10):1329-1333
A series of tri-substituted thiourea derivatives were synthesized by the reaction of 1,3,5-triacetylbenzoyl isothiocyanate with aminoacids and aniline derivatives. All thiourea derivatives were characterized by FT-IR, 1H and 13C NMR spectroscopy. Antibacterial activities against wild-type Escherichia coli American Type Culture Collection 8739 were determined by use of the turbidimetric methodto evaluate the effect of varying amino groups on the synthesized thioureas. Tris-thiourea derivatives bearing ortho-chloroaryl substituents showed excellent antibacterial activity against E. coli with minimal inhibitory concentration (MIC) of 96 ppm. The optimum inhibition was dependent on the type of amines and the position of the halogen in aniline. 相似文献
1000.
Loong Chuen Lee Muhammad Ismail Ab Samad Mohamad Azlan Mohd Ismail 《Journal of Analytical Chemistry》2016,71(7):723-729
As a non-destructive analytical method, Raman spectroscopy often provides insufficient information to identify or differentiate the ink used for the preparation of a questioned document. In this study, blue and black ballpoint pen inks deposited on paper substrate were examined in situ by conventional Raman spectroscopy. Inks were successfully classified based on the total number of prominent bands in Raman spectra. It was found that more than 90% of the samples of the same type and color could be differentiated visually using only Raman spectra, i.e. 94 and 95% for blue and black inks, respectively. As a result of this study, a flow chart has been constructed for blue and black ballpoint pen inks allowing their systematic identification. Raman spectroscopy proved to be a fast and precise technique for forensic ink analysis. 相似文献