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711.
Jeong Junho Briere Tina M. Sahoo N. Das T. P. Nishiyama K. Ohira S. Nagamine K. 《Hyperfine Interactions》2001,136(3-8):763-767
The trapping sites for muon and muonium in β-phase ferromagnetic p-NPNN have been determined by the first-principles Unrestricted
Hartree–Fock procedure. Four trapping sites are found for the muon near the two nitrogen and two oxygen atoms of the two NO
groups. For the singlet state of trapped muonium, two trapping sites are found near the two oxygens of two NO groups and for
the triplet state two trapping sites are found near the two oxygens of the NO2 group. The observed μSR signal at zero field with frequency 2.1 MHz is assigned to the singlet muonium sites near the two
oxygens of the two NO groups and the high frequency signal ascribed to an isotropic hyperfine constant of 400 MHz is assigned
to the two trapped muon sites near the two nitrogen atoms of the two NO groups.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献
712.
Bikash Sahoo H. G. Sharma 《应用数学和力学(英文版)》2007,28(11):1467-1477
An analysis is carried out to study the steady flow and heat transfer charac- teristics from a continuous flat surface moving in a parallel free stream of an electrically conducting non-Newtonian viscoelastic fluid.The flow is subjected to a transverse uni- form magnetic field.The constitutive equation of the fluid is modeled by that for a second grade fluid.Numerical results are obtained for the distribution of velocity and temperature profiles.The effects of various physical parameters like viscoelastic param- eter,magnetic parameter and Prandtl number on various momentum and heat transfer characteristics are discussed in detail and shown graphically. 相似文献
713.
Kulbir Sandip Das Tarali Devi Mrigaraj Goswami Mahesh Yenuganti Prabhakar Bhardwaj Somnath Ghosh Subash Chandra Sahoo Pankaj Kumar 《Chemical science》2021,12(31):10605
Nitrate reductases (NRs) are molybdoenzymes that reduce nitrate (NO3−) to nitrite (NO2−) in both mammals and plants. In mammals, the salival microbes take part in the generation of the NO2− from NO3−, which further produces nitric oxide (NO) either in acid-induced NO2− reduction or in the presence of nitrite reductases (NiRs). Here, we report a new approach of VCl3 (V3+ ion source) induced step-wise reduction of NO3− in a CoII-nitrato complex, [(12-TMC)CoII(NO3−)]+ (2,{CoII–NO3−}), to a CoIII–nitrosyl complex, [(12-TMC)CoIII(NO)]2+ (4,{CoNO}8), bearing an N-tetramethylated cyclam (TMC) ligand. The VCl3 inspired reduction of NO3− to NO is believed to occur in two consecutive oxygen atom transfer (OAT) reactions, i.e., OAT-1 = NO3− → NO2− (r1) and OAT-2 = NO2− → NO (r2). In these OAT reactions, VCl3 functions as an O-atom abstracting species, and the reaction of 2 with VCl3 produces a CoIII-nitrosyl ({CoNO}8) with VV-Oxo ({VV O}3+) species, via a proposed CoII-nitrito (3, {CoII–NO2−}) intermediate species. Further, in a separate experiment, we explored the reaction of isolated complex 3 with VCl3, which showed the generation of 4 with VV-Oxo, validating our proposed reaction sequences of OAT reactions. We ensured and characterized 3 using VCl3 as a limiting reagent, as the second-order rate constant of OAT-2 (k2/) is found to be ∼1420 times faster than that of the OAT-1 (k2) reaction. Binding constant (Kb) calculations also support our proposition of NO3− to NO transformation in two successive OAT reactions, as Kb(CoII–NO2−) is higher than Kb(CoII–NO3−), hence the reaction moves in the forward direction (OAT-1). However, Kb(CoII–NO2−) is comparable to Kb{CoNO}8, and therefore sequenced the second OAT reaction (OAT-2). Mechanistic investigations of these reactions using 15N-labeled-15NO3− and 15NO2− revealed that the N-atom in the {CoNO}8 is derived from NO3− ligand. This work highlights the first-ever report of VCl3 induced step-wise NO3− reduction (NRs activity) followed by the OAT induced NO2− reduction and then the generation of Co-nitrosyl species {CoNO}8.Single metal-induced reduction of NO3− → {NO2−} → NO via oxygen atom transfer reaction. 相似文献
714.
Padmini Sahoo Purva Chibde Satyabrata Das Subhrashis Banerjee Bhupendra P. Mali Dr. Kumar Vanka Dr. Rajesh G. Gonnade Prof. Dr. Cem. B. Yildiz Dr. Moumita Majumdar 《欧洲无机化学杂志》2023,26(29):e202300249
A 12-membered zwitterionic tetrastanna(II) cycle 1 having a crown ether-like topology has been isolated from the deprotonation of 1,1′-methylenediimidazole ( B ) with two equivalents of Sn[N(SiMe3)2]2 ( A ). The solid-state structure and NMR analysis confirms the tetrastanna(II) cycle 1 to be comprised of two stannate(II) and two stannyliumylidene ion pairs in alternating positions of the heterocycle. Computational analysis shows greater nucleophilicity at the proximally located stannate(II) centers. Nonetheless, the tetrastanna(II) cycle 1 remains poorly reactive due to engagement of SnII lone pair electrons in intramolecular donor-acceptor interactions. Simple deprotonation reaction between Sn[N(SiMe3)2]2 ( A ) and N-(diisopropylphenyl)imidazole ( C ) in equimolar ratio has led to a stannylene 2 , involving the formation of a Sn−C covalent bond with the anionic imidazol-2-yl carbon center along with the release of NH(SiMe3)2. Compound 2 exists as a dimer, where the unsubstituted ring nitrogen atom coordinated intermolecularly to the other stannylene center. 相似文献
715.
Fluorescence-based detection technique using coordination polymer has been considered an attractive alternative over conventional approaches. Herein, a new luminescent zinc(II) coordination polymer, [Zn(4-ABPT)(NIPA)(H2O)], SSICG-5 , is synthesized by using a Lewis acidic Zn(II) ion, aromatic nitro group containing ligand 5-nitroisophthalic acid (H2NIPA), and basic −NH2 rich ligand 3,5-di(pyridine-4-yl)-4H-1,2,4-triazol-4-amine (4-ABPT). SSICG-5 can detect Fe3+ and Cr2O72− selectively with a LOD of 0.16 μM and 1.94 μM, respectively. Additionally, carbon dioxide (CO2) fixation via one-pot CO2 cycloaddition reaction has significant importance for reduced waste formation, minimizing reaction time and lowering chemical usage. Zn metal centre of SSICG-5 possesses a replaceable coordinated water molecule. The active metal sites combined with the Lewis acidic and basic sites of the ligands make SSICG-5 an ideal bifunctional heterogeneous catalyst for efficient CO2 cycloaddition reaction under room temperature (RT), solvent-free conditions. Notably, SSICG-5 exhibits near quantitative conversion (turnover number (TON) of 198) of propylene oxide to its carbonate compound under mild reaction conditions. 相似文献
716.
Sardar Kripasindhu Bolagam Ravi Sahoo Sumanta Kumar Kaneko Satoru Kurouchi Masahito Chang Kao-Shuo Su Yen-Hsun Ting Jyh-Ming Yoshimura Masahiro 《Journal of Solid State Electrochemistry》2023,27(4):857-864
Journal of Solid State Electrochemistry - The investigation of metal oxides with delafossite-type crystal structure for electrochemical energy storage applications is an emerging area.... 相似文献
717.
In the present study, we investigate the anisotropic stellar solutions admitting Finch-Skea symmetry (viable and non-singular metric potentials) in the presence of some exotic matter fields, such as Bose-Einstein Condensate (BEC) dark matter, the Kalb-Ramond fully anisotropic rank-2 tensor field from the low-energy string theory effective action, and the gauge field imposing \begin{document}$ U(1) $\end{document} ![]()
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symmetry. Interior spacetime is matched with both Schwarzchild and Reissner-N?rdstrom vacuum spacetimes for BEC, KB, and gauge fields. In addition, we study the energy conditions, Equation of State (EoS), radial derivatives of energy density and anisotropic pressures, Tolman-Oppenheimer-Volkoff equilibrium condition, relativistic adiabatic index, sound speed, and surface redshift. Most of the aforementioned conditions are satisfied. Therefore, the solutions derived in the current study lie in the physically acceptable regime. 相似文献
718.
Dr. Shubham Dutta Prof. Dr. Akhila K. Sahoo 《Angewandte Chemie (International ed. in English)》2023,62(12):e202300610
A Pd-catalyzed three-component syn-1,2-arylmethylation of internal alkynes (ynamides/yne-acetates/alkynes) is described. The readily available and bench stable coupling partners iodo-arenes, and methyl boronic acid are successfully used in this coupling strategy to access the methyl-containing tetra-substituted olefins; the scope is broad showing excellent functional-group tolerance. Notably, the transformation is regio- as well as stereoselective. The biologically relevant motifs (BRM) bearing iodo-arenes and ynamides are also used for the late-stage syn-1,2-arylmethylation of alkynes. Aryl-alkylation, aryl-trideuteriomethylation, alkynyl-methylation, and alkenyl-methylation of ynamides are also presented. The Me-substituted alkenes are further transformed into synthetically important β-amino-indenones and α-fluoro-α′-methyl ketones. 相似文献
719.
In this work, the anion-responsive conduct of a Ru(II)-bipyridine complex incorporating pyrazolyl-bis (benzimidazole) ligand is thoroughly investigated in acetonitrile and water via absorption and emission spectroscopy as well as by square-wave voltammetry (SWV). Substantial alteration of the photo-redox behavior of the complex is observed in the presence of the selected anions. The free form of the complex exhibits emission indicating the “on-state”, while inclusion of anions leads to quenching of emission and represents the “off-state”. The restoration of the initial state of the complex is feasible in the presence of acid and the process is reversible and can be recycled. In essence, the complex functions as anion- and acid-responsive molecular switches. Additionally, we applied herein neural network based deep learning methodologies, viz. Artificial Neural Networks (ANNs) and Adaptive Neuro-Fuzzy Inference System (ANFIS)} for thorough analysis and fully understand the multi-channel anion sensing behavior of the complex. 相似文献
720.