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991.
Two tridentate N,N,O donor Schiff bases, HL1 (4-(2-ethylamino-ethylimino)-pentan-2-one) and HL2 (3-(2-amino-propylimino)-1-phenyl-butan-1-one) on reaction with CuII acetate in presence of triethyl amine yielded two basal-apical, mono-atomic acetate oxygen-bridging dimeric copper(II) complexes, [Cu2L12(OAc)2] (1), [Cu2L22(OAc)2] (2). Whereas two other similar tridentate ligands HL3 (4-(2-amino-propylimino)-pentane-2-one) and HL4 (3-(2-amino-ethylimino)-1-phenyl-butan-1-one) under the same conditions produced a mixture of the corresponding dimers and a one-dimensional alternating chain of the dimer and copper acetate moiety, [Cu4L32(OAc)6]n (3) and [Cu4L42(OAc)6]n (4), formed by a very rare μ3 bridging mode of the acetate ion. All four complexes (1–4) have been characterized by X-ray crystallography. The isotropic Hamiltonian, H = −JS1S2 has been used to interpret the magnetic data. Magnetic measurements of 1 and 2 in the temperature range 2–300 K reveal a very weak antiferromagnetic coupling for both complexes (J = −0.56 and −1.19 cm−1 for 1 and 2, respectively). 相似文献
992.
Surface enhanced Raman scattering of 2,2' biquinoline adsorbed on colloidal silver particles 总被引:1,自引:0,他引:1
Chowdhury J Ghosh M Misra TN 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2000,(11):2107-2115
Surface enhanced Raman scattering (SERS) in silver sol and normal Raman spectra in the bulk and in solution of 2,2' biquinoline (BQ) molecule have been investigated. The observed Raman bands along with their corresponding FTIR bands have been assigned based on the established assignments of the vibrational bands of the parent napthalene and quinoline molecules. Existence of both the cis and trans form of the BQ molecule in solution and in the bulk are inferred from the normal Raman and FTIR spectra, whereas SERS study reveal that in the surface adsorbed state the molecule exists in the cis form. Definite evidence of the charge transfer interaction to the overall contribution in the SER enhancement have been reported. The excitation profile also supports the CT interaction. Estimated enhancement factor of the principal SERS bands indicate that the molecule is adsorbed on the silver surface through both the nitrogen atoms with the molecular plane almost perpendicular to the surface. This preferred orientation of the molecule is in conformity with its existence in the cis form in the surface adsorbed state. 相似文献
993.
Manisha Gurnani Prangya Rath Abhishek Chauhan Anuj Ranjan Arabinda Ghosh Rup Lal Nobendu Mukerjee Nada H. Aljarba Saad Alkahtani Vishnu D. Rajput Svetlana Sushkova Evgenya V. Prazdnova Tatiana Minkina Tanu Jindal 《Molecules (Basel, Switzerland)》2022,27(6)
Antibiotic resistance is one of the major growing concerns for public health. Conventional antibiotics act on a few predefined targets and, with time, several bacteria have developed resistance against a large number of antibiotics. The WHO has suggested that antibiotic resistance is at a crisis stage and identification of new antibiotics and targets could be the only approach to bridge the gap. Filamentous Temperature Sensitive-Mutant Z (Fts-Z) is one of the promising and less explored antibiotic targets. It is a highly conserved protein and plays a key role in bacterial cell division by introducing a cytokinetic Z-ring formation. In the present article, the potential of over 165 cyanobacterial compounds with reported antibiotic activity against the catalytic core domain in the Fts-Z protein of the Bacillus subtilis was studied. The identified cyanobacterial compounds were screened using the GLIDE module of Maestro v-2019-2 followed by 100-ns molecular dynamics (MD) simulation. Ranking of the potential compound was performed using dock score and MMGBSA based free energy. The study reported that the docking score of aphanorphine (−6.010 Kcalmol−1) and alpha-dimorphecolic acid (ADMA) (−6.574 Kcalmol−1) showed significant role with respect to the reported potential inhibitor PC190723 (−4.135 Kcalmol−1). A 100 ns MD simulation infers that Fts-Z ADMA complex has a stable conformation throughout the progress of the simulation. Both the compounds, i.e., ADMA and Aphanorphine, were further considered for In-vitro validation by performing anti-bacterial studies against B. subtilis by agar well diffusion method. The results obtained through In-vitro studies confirm that ADMA, a small molecule of cyanobacterial origin, is a potential compound with an antibacterial activity that may act by inhibiting the novel target Fts-Z and could be a great drug candidate for antibiotic development. 相似文献
994.
995.
Hall mobility and magnetoresistance coefficient for the two-dimensional (2D) electron transport parallel to the heterojunction
interfaces in a single quantum well of CdSe are calculated with a numerical iterative technique in the framework of Fermi-Dirac
statistics. Lattice scatterings due to polar-mode longitudinal optic (LO) phonons, and acoustic phonons via deformation potential
and piezoelectric couplings, are considered together with background and remote ionized impurity interactions. The parallel
mode of piezoelectric scattering is found to contribute more than the perpendicular mode. We observe that the Hall mobility
decreases with increasing temperature but increases with increasing channel width. The magnetoresistance coefficient is found
to decrease with increasing temperature and increase with increasing magnetic field in the classical region.
相似文献
996.
Tapas Ghosh 《Transition Metal Chemistry》2006,31(4):560-565
Reaction of VOSO4 with the tridentate ONO donor ligand derived from the condensation of acetylhydrazide with either 2-hydroxybenzaldehyde (H2L1) or 2-hydroxyacetophenone (H2L2) (general abbreviation H2L) in an equimolar ratio in the presence of two equivalents of sodium acetate in aqueous-methanolic medium in air produces
yellow dioxovanadium(V) complexes of the type, [VvO2(H+-L)], (1) and (2) in good yield. Aerial oxygen is most likely the oxidant (for the oxidation of VIV→VV) assisted by the ligand basicity. Complexes are characterized by elemental analyses and by i.r., n.m.r. and u.v.–vis. spectroscopies.
I.r. spectra of the complexes indicate the tridentate dinegative forms of the ligands. The 1H-n.m.r. spectrum of (2) in CD3CN solvent indicates the presence of a strongly deshielded N–H proton. Conductivity measurements in DMF solution indicate
that the complexes are non-electrolytic and so the H+ ion is strongly bonded probably with the uncoordinated imine-N nitrogen of the coordinated Schiff base moiety. Both complexes
exhibit only the LMCT band in the u.v. region in MeOH and they are electroactive, displaying an irreversible reduction peak
near −0.35 V versus s.c.e. in methanol solution. Methanol solutions of the complexes are reversibly reduced by ascorbic acid to the corresponding
VIV analogue as is evident from their u.v.–vis. spectra. The CH2Cl2 suspension of these complexes (1) and (2) reacts separately with 8-hydroxyquinoline (Hhq) in air to produce the mixed-ligand complexes of the type [VvO(L)(hq)]. 相似文献
997.
Binay Kumar Bhattacharya Subir Kumar Ghosh Thomas Caton Shermer 《Computational Geometry》2006,33(3):165-173
In this paper, we present a linear time algorithm to remove winding of a simple polygon P with respect to a given point q inside P. The algorithm removes winding by locating a subset of Jordan sequence that is in the proper order and uses only one stack. 相似文献
998.
We have studied the emission of neutrinos from a rotating hybrid star. We find that the emission is predominantly confined to a very small angle, provided the core of the star is in a mixed phase of quarks and hadrons and the size of such a mixed phase is small. Annihilation of neutrinos to produce gamma rays has been discussed. The estimated duration of the burst is found to be within the observational range. 相似文献
999.
Two new, easy-to-prepare dipyrrolyl derivatives endowed with electron-withdrawing quinone or dicyano functionalities in their
architecture permit the detection of fluoride ions under visual (naked-eye) as well as optical (absorption and fluorescence)
and electrochemical conditions in organic solvents 相似文献
1000.
R. Lorenz A. Lande W. Biltz F. M. Jaeger B. Kapma E. D. Eastman E. Neuberg C. A. Kraus W. W. Luccase M. Neuberg W. W. Lucasse M. Abribat C. Marie W. A. Noyos Jr. P. A. Thiesen J. L. R. Morgan O. M. Lammer H. Remy P. Walden F. A. Smith H. I. Schlesinger F. H. Reed C. de Rhoden und J. Ch. Ghosh 《Fresenius' Journal of Analytical Chemistry》1928,75(3-4):123-128
Ohne Zusammenfassung 相似文献