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211.

The transverse momentum spectra of protons participated in the collision processes calculated using UrQMD model simulations have been compared with the pT spectra of participant protons, obtained experimentally in interactions of protons beam with carbon nuclei at momenta of 4.2 GeV/c. Spectral temperatures of participant protons obtained in the experimental and UrQMD model simulated interactions of protons beam with carbon nuclei have been calculated by fitting both spectra with four different fitting functions i.e. Hagedorn Thermodynamic, Boltzmann distribution, Gaussian and exponential functions. These functions are used commonly for describing the hadrons spectra and their spectral temperatures. The most suitable fitting functions among these four functions have also been recommended.

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212.
This study deals with the synthesis and physicochemical investigation of gold nanoparticles using an aqueous extract of Monotheca buxifolia (Flac.). On the treatment of aqueous solution of tetrachloroauric acid with the plant extract, gold nanoparticles were rapidly fabricated. The synthesized particles were characterized by UV–Vis spectrophotometry (UV), Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray (EDX) and Scanning electron microscopy (SEM). The formation of AuNPs was confirmed by noting the change in color through visual observations as well as via UV–Vis spectroscopy. UV?Vis spectrum of the aqueous medium containing gold nanoparticles showed an absorption peak at around 540 nm. FTIR was used to identify the chemical composition of gold nanoparticles and Au-capped plant extract. The presence of elemental gold was also confirmed through EDX analysis. SEM analysis of the gold nanoparticles showed that they have a uniform spherical shape with an average size in the range of 70–78 nm. This green system showed to be better capping and stabilizing agent for the fine particles. Further, the antioxidant activity of Monotheca buxifolia (Flac.) extract and Au-capped with the plant extract was also evaluated using FeCl3/K3[Fe(CN)]6 in vitro assay.  相似文献   
213.
Substituted benzoic acid and cinnamic acid esters are of interest as tyrosinase inhibitors and the development of such inhibitors may help in diminishing many dermatological disorders. The tyrosinase enzyme has also been linked to Parkinson's disease. In view of hydroxylated compounds having ester and amide functionalities to potentially inhibit tyrosinase, we herein report the synthesis and crystal structures of two amide‐based derivatives, namely N‐(4‐acetylphenyl)‐2‐chloroacetamide, C10H10ClNO2, (I), and 2‐(4‐acetylanilino)‐2‐oxoethyl cinnamate, C19H17NO4, (II). In compound (I), the acetylphenyl ring and the N—(C=O)—C unit of the acetamide group are almost coplanar, with a dihedral angle of 7.39 (18)°. Instead of esterification, a cheaper and more efficient synthetic method has been developed for the preparation of compound (II). The molecular geometry of compound (II) is a V‐shape. The acetamide and cinnamate groups are almost planar, with mean deviations of 0.088 and 0.046 Å, respectively; the dihedral angle between these groups is 77.39 (7)°. The carbonyl O atoms are positioned syn and anti to the amide carbonyl O atom. In the crystals of (I) and (II), N—H…O, C—H…O and C—H…π interactions link the molecules into a three‐dimensional network.  相似文献   
214.
Poly(diallyldimethylammonium chloride) (PDADMAC) and poly(sodium 4-styrenesulfonate) (PSS) have been consecutively adsorbed onto 1.5-microm charged silica (SiO2) particles. Time-dependent adsorption studies indicate that, due to the strong ionic charge of the dissociated polycation in water, adsorption is complete in less than 30 min. Indications of the maximum adsorption density, changes in surface charge, and stability of the layered particles are demonstrated through adsorption isotherms and electrophoretic mobility (EPM) measurements. Further stability of the PDADMAC layer is demonstrated through multiwashing with ultra pure deionized water. Preliminary desorption studies of the PSS layer also illustrate a stabilized two-layer system. Due to the nature of the electrostatic charges on the surface of the SiO2 core particles and both polyelectrolytes in aqueous media, the use of polyelectrolytes as layering elements serves as a model for the assembly of time-released drug delivery particle systems.  相似文献   
215.
Effect of electron beam irradiation on the thermal and mechanical properties of poly(ethylene-co-vinyl acetate) (EVA)/clay nanocomposites prepared by melt blending method has been investigated. The hot set test results show that elongation at high temperature under static load decreased with the increase of irradiation dose. The tensile modulus increased continuously with increasing dose. While the tensile strength increased up to 100 kGy, it decreased with further increase in dose. The elongation at break decreased continuously with increasing dose. Thermogravimetric analysis showed that thermal stability of the EVA/clay nanocomposites improved with increasing dose. The improvement in the mechanical and thermal properties is attributed to the formation of radiation-induced crosslinking as evidenced by the gel content results.  相似文献   
216.
Four new organic/inorganic coordination polymers, [Cd(C(10)H(8)N(2))(2)(H(2)O)(2)(NO(3))(2)](n)(1), [Co(C(10)H(8)N(2))(H(2)O)NO(3)CH(3)OH](n)(2), [Cu(C(10)H(8)N(2))(CH(3)OH)(NO(3))(2)](n) (3), and [Cu(C(10)H(8)N(2))(hfac)(2)](n)(4), were synthesized by using the rigid ligand 1,2-bis(3-pyridyl)ethyne (3,3'-DPA). Complex 1 crystallizes in space group P2/n: a = 12.462(2) A, b = 9.485(1) A, c = 13.383(2) A, beta = 96.629(2) degrees, V = 1559.6(3) A(3), Z = 4. Complex 2 crystallizes in space group Fddd: a = 9.248(4) A, b = 19.982(7) A, c = 35.093(16) A, V = 6485.0(4) A(3), Z = 8. Complex 3 crystallizes in space group I2/a: a = 18.315(2) A, b = 8.517(1) A, c = 20.494(3) A, beta = 104.042(2) degrees, V = 3101.2(7) A(3), Z = 8. Complex 4 crystallizes in space group P21/c: a = 6.576(1) A, b = 16.189(1) A, c = 11.653(1) A, beta = 91.337(1) degrees, V = 1240.3(2) A(3), Z = 2. The coordination polymers display a variety of structural architectures, ranging from sinusoidal and zigzag chains (1, 3, 4) to two-dimensional channel-type architectures (2). The effects of the orientation of the nitrogen atom in the pyridine rings on the resultant structures are discussed.  相似文献   
217.
The long, rigid ligands 1,4-bis[(3-pyridyl)ethynyl]benzene (L1) and 1,4-bis[(4-pyridyl)ethynyl]benzene (L2) were used in the synthesis of 10 new organic-inorganic coordination frameworks, each of them adopting different structural motifs. Synthesis, single-crystal X-ray structure determination, and spectroscopic and thermogravimetric analyses are presented. The reactions between M(NO3)2 x xH2O; M = Cd(II), Cu(II), and Co(II); x = 3-6 and Cu(hfac)2 x H2O [hfac = bis(hexafluoroacetylacetonato)] with L1 afforded the following one-dimensional zigzag chain structures: [Cd(C20H12N2)0.5(NO3)(CH3OH)]n (1, monoclinic, C2/c; a = 7.586(1) A, b = 23.222(1) A, c = 13.572(1) A, beta = 92.824(1), Z = 4); [{Cu(C20H12N2)(NO3)2(CH3OH)} x CH3OH]n (2, orthorhombic, P2(1)2(1)2(1); a = 8.589(1) A, b = 15.766(1) A, c = 17.501(1) A, Z = 4); [Co(C20H12N2)2(NO3)2(H2O)2] (5, triclinic, P1; a = 7.493(1) A, b = 8.948(1) A, c = 14.854(1) A, alpha = 100.427(1), beta = 97.324(1), gamma = 110.901(1), Z = 1); [Cu(C20H12N2)(hfac)2]n (4, monoclinic, C2/c, a = 18.828(1) A, b = 14.671(1) A, c = 13.427(1) A, beta = 90.447(1) degrees, Z = 4). Moreover, the minority phase compound formed from Cu(NO3)2 x 3H2O and L1 yielded a metallocyclic chain structure, [Cu(C20H12N2)(NO3)]n (3, triclinic, P; a = 8.728(1) A, b = 10.018(1) A, c = 11.893(1) A, alpha = 109.991(1), beta = 97.109(1), gamma = 115.542(1), Z = 1). In addition to the dinuclear coordination complex 5, all other polymeric structures (1-4) from L1 are composed of interpenetrating 2D and 3D cross-linked zigzag chains via hydrogen-bonding interactions. The reactions between M(NO3)2 x xH2O; M = Cd(II), Cu(II), and Co(II); x = 3-6 and Cu(hfac)2 x H2O [hfac = bis(hexafluoroacetylacetonato)] and L2 were dependent on the nature of the metal center and resulted in the formation of four different interpenetrating and noninterpenetrating compounds (6-10): [Co(C20H12N2)1.5(NO3)2]n (6, triclinic, P; a = 14.172(1) A, b = 15.795(1) A, c = 18.072(1) A, alpha = 115.380(1), beta = 101.319(1), gamma = 93.427(2), Z = 4), which consists of T-shaped building blocks assembled into three-dimensional interpenetrating polycatenated ladders; [Cd(C20H12N2)2(NO3)2]n (7, monoclinic, I2/a; a = 11.371(1) A, b = 20.311(2) A, c = 15.240(2) A, beta = 100.201(2) degrees, Z = 4), which adopts a two-dimensional noninterpenetrating square-grid motif; [Cu(C20H12N2)(hfac)2]n (8, monoclinic, I2/a; a = 11.371(1) A, b = 20.311(2) A, c = 15.240(2) A, beta = 100.201(2) degrees, Z = 4), composed of three sets of distinct one-dimensional linear chains; [Cu(C20H12N2)(EtOH)(NO3)2] [Cu(C20H12N2)1.5(NO3)2] x 2EtOH (9, triclinic, P; a = 12.248(2) A, b = 13.711(3) A, c = 18.257(4) A, alpha = 108.078(4) degrees, beta = 97.890(4) degrees, gamma = 103.139(5) degrees, Z = 2) and [Cu(C20H12N2)(MeOH)(NO3)2] [Cu(C20H12N2)1.5(NO3)2] x 2MeOH (10, triclinic, P; a = 12.136(1) A, b = 13.738(2) A, c = 17.563(3) A, alpha = 107.663(3) degrees, beta = 94.805(4) degrees, gamma = 104.021(4) degrees, Z = 2). Both 9 and 10 stack into infinite interpenetrating ladders through bundles of infinite chains and are described in our preliminary communication.  相似文献   
218.
The synthesis and characterization of some novel compounds of organotin(IV) chlorides with monomethyl glutarate is reported; the ligand molecule appears to be bound to the tin atom through the carbonyl oxygen. The results obtained through 1H‐13C‐119Sn NMR, FT‐IR and 119Sn Mössbauer spectra show that the diorganotin(IV) complexes have hexacoordination with octahedral geometry. Biological screening of the complexes reveals that the diorganotin(IV) complexes show significant activity against all microorganisms.  相似文献   
219.
Benzene-1,3-diamidoethanethiol (BDETH2) is an exceptional precipitant for removing soft heavy metals from water. The present work will detail the bonding arrangement of BDETH2 to the metals Cd, Hg, and Pb, along with the full characterization data of the BDET-M compounds. It was found that the Hg compound has a linear S-M-S geometry. The characterization data consisted of Mp, EA, IR, Raman, MS, XANES, EXAFS, and solid-state multinuclear NMR.  相似文献   
220.
Five novel triorganotin(IV) complexes have been synthesized by refluxing trimethyl, triethyl, tributyl, triphenyl and tribenzyltin chloride with Cephlaxine. These compounds were characterized by spectroscopic (IR, IH, 13C, 119Sn NMR) techniques and elemental analysis. The results obtained through these techniques are in full agreement with the proposed 1:1 stoichiometry. The synthesized compounds were than tested against various microorganisms and fungi. The results of new products obtained showed that the triphenyltin(IV) complex displayed promising activity against all types of bacteria and fungi used while all other compounds showed significant antibacterial and antifungal activity.  相似文献   
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