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41.
William H. Watson Satish G. Bodige Jie Liu Michael G. Richmond 《Structural chemistry》2003,14(4):369-375
The reactivity of the bidentate ligand 2,3-bis(diphenylphosphino)-N-phenylmaleimide (bppm) with the tetrahedrane cluster PhCCo3(CO)9 under thermolysis and ETC conditions has been studied and found to ultimately give Co3(CO)6[μ2,η2,η1-C(Ph) ${\text{C}}{\text{ = }}{\text{ = }}{\text{C(PPh}}_{\text{2}} {\text{)C(O)NPhC}}$ (O)](μ2-PPh2) as the final product. The intermediate cluster compound PhCCo3(CO)7(bppm), which was observed by IR and 31P NMR spectroscopies, readily and rapidly transforms into the product cluster under the reactions conditions. The solid-state structure of Co3(CO)6[μ2,η2,η1-C(Ph)fptt(O)](μ2-PPh$_{2})$ was unequivocally determined by X-ray crystallography. Co3(CO)6[μ2, η2, η1-C(Ph)Õ(O)](μ2-PPh2) crystallizes in the monoclinic space group P2(1)/n, a = 11.825(5) Å, b = 31.20(1) Å, c = 11.831(5) Å, β = 108.720(7)°, V = 4134(7) Å3, Z = 4, d calc = 1.567 Mg/m3; R = 0.0350, R w = 0.0817 for 4747 observed reflections with I > 2σ(I). The X-ray structure confirms the coupling of the benzylidyne ligand with the bppm ligand in Co3(CO)6[μ2,η2,η1-C(Ph)Õ(O)](μ2-PPh2). The course of the thermolysis reaction is identical to those reactions carried out with the related diphosphine ligands bma and bpcd. The utility of electron-transfer catalysis (ETC) in the preparation of PhCCo3(CO)7(bppm) is discussed relative to the reduction potential of the bppm ligand and the tricobalt cluster PhCCo3(CO)9. 相似文献
42.
Kumaraswamy S Kommana P Kumar NS Swamy KC 《Chemical communications (Cambridge, England)》2002,(1):40-41
New modes of 1,3-dipolar cycloaddition are uncovered by the isolation of [CH2(6-t-Bu-4-Me-C6H2O)2]P(C(CO2Me)C(CO2Me)N[NP(N3)(OC6H2-6-t-Bu-4-Me)2CH2]N) (3) and [CH2(6-t-Bu-4-Me-C6H2O)2]P(C(CO2Me)C(CO2Me)C(O)N) (4) on treating [CH2(6-t-Bu-4-Me-C6H2O)2]P-X [X = N3 (1) and NCO (2)] with the dipolarophile MeO2CC identical to CCO2Me; compound 4 undergoes an unprecedented ring expansion upon addition of 2-(methylamino)ethanol to afford the spirocycle [CH2(6-t-Bu-4-Me-C6H2O)2]P(OCH2CH2N(Me)CH(CO2Me)CH(CO2Me)C(O)N) (5). 相似文献
43.
S. F. Patil N. G. Adhyapak P. R. Patil 《Journal of Radioanalytical and Nuclear Chemistry》1985,95(1):13-20
Tracer-diffusion of Zn2+ ions in the presence of CoSO4 is studied at 25°C in 1% agar gel over a concentration range of 10–5 to 0.25M using a zone-diffusion technique. The deviations observed between experimental and theoretical values of diffusion coefficients are explained by considering different types of interactions occurring in the ion-gel-water system. Further, study of the obstruction, effect in the diffusion of Zn2+ ions at different concentrations of CoSO4 reveals that the -value decreases with increasing concentration of the electrolyte. This observation is accounted on the basis of competitive hydration between ions and agar molecules. 相似文献
44.
The dimensional analyses of the position and momentum variances‐based quantum mechanical Heisenberg uncertainty measure, as well as the entropic information measures given by the Shannon information entropy sum and the product of Fisher information measures are carried out for two widely used nonrelativistic isotropic exponential‐cosine screened Coulomb potentials generated by multiplying the superpositions of (i) Yukawa‐like, ?Z(e?μr/r), and (ii) Hulthén‐like, ?Zμ(1/(eμr ? 1)), potentials by cos(bμr) followed by addition of the term a/r2, where a and b ≥ 0, μ are the screening parameters and Z, in case of atoms, denotes the nuclear charge. Under the spherical symmetry, all the information measures considered are shown to be independent of the scaling of the set [μ, Z] at a fixed value of μ/Z, a, and b and the other parameters defining the superpositions of the potentials. Numerical results are presented, which support the validity of the scaling properties. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007 相似文献
45.
The reaction of 3,6-diphenyl-1,2,4,5-tetrazine 1 with cis,cis-cycloocta-1,5-diene 7 has been studied with a view to preparing some interesting dihydropyridazine derivatives. Refluxing a mixture of 1 with excess of 7 in benzene solution for 8hr resulted in the formation of a mixture of products consisting of 1,4-diphenyl-10a-hydroperoxy-4a, 5,6,9,10,10a-hexahydrocycloocta[d]pyridazine (8, 27%) and 2,4a,5,6,8,10a,11,12-octahydro-1,4,7,10-tetraphenyldipyridazo[4,5-a:4',5'-e]cyclooctene ( However, when the reaction of 1 with 7 was carried out in refluxing benzene for nearly 40 hr, the products formed were a 14% yield of 8, a 17% yield of 9 and a 37% yield of 1,4-diphenyl-5,6,9,10-tetrahydrocycloocta[d]pyridazine (10). Neat heating of 1 with 7 around 150° for 10 hr, on the other hand, gave a 20% yield of 9, as the only isolable product. Thermolysis of 8 around 155° gave a mixture of products consisting of 2-oxocyclooct-5-enyl phenyl ketone N-benzoylhydrazone (15,30%) and 1H-3-phenyl-4,5,8,9-tetrahydrocycloocta[d]pyrazole (16, 22%). Nickel peroxide-oxidation of the adduct 9 gave a 67% yield of 1,4,7,10-tetraphenyldipyridazo[4,5-a:4',5'-e]cyclooctene (27). Acetylation of 9, on the other hand, gave a 70% yield of 2,3,8,9-tetraacetyl-2,3,5,6,8,9,11,12-octahydro-1,4,7,10-tetraphenyldipyridazo[4,5-a:4',5'-e]cyclooctene(28). 相似文献
46.
V. R. Bhandiwad Rajendra Swarup S. K. Patil 《Journal of Radioanalytical and Nuclear Chemistry》1979,52(1):5-14
The extraction of Np(IV), Pu(IV) and U(VI) from aqueous hydrochloric acid into quaternary amines has been studied. The dependence
of the distribution coefficient on amine concentration suggests that the actinide ions extracted are NpCl
6
2−
PuCl
6
2−
and UO2Cl
4
2−
. This is further supported by the absorption spectra of the amine extracts of these actinide ions. Based on the extraction
data obtained, a simple method for the separation of typical metal ions such as Cs, lanthanides and Zr from U(VI) and Pu(IV)
is suggested. 相似文献
47.
Triphenylarsine oxide is proposed as an extractant for the solvent extraction of uranium and thorium salicylates. The optimum extraction conditions are established by studying the various parameters such as pH, sodium salicylate concentration, triphenylarsine oxide concentration, diluents and shaking time. The probable extracted species as ascertained by logD-logC plots are UO2(Hsal)2·2TPAsO and Th(Hsal)4·2TPAsO. The method is simple, fast, precise and permits the determination of uranium and thorium in monazite sand samples. 相似文献
48.
Wilmer H. Perera Siddanagouda R. Shivanagoudra Jose L. Prez Da Mi Kim Yuxiang Sun Guddadarangavvanahally K. Jayaprakasha Bhimanagouda S. Patil 《Molecules (Basel, Switzerland)》2021,26(4)
Diabetes mellitus is a chronic disease and one of the fastest-growing health challenges of the last decades. Studies have shown that chronic low-grade inflammation and activation of the innate immune system are intimately involved in type 2 diabetes pathogenesis. Momordica charantia L. fruits are used in traditional medicine to manage diabetes. Herein, we report the purification of a new 23-O-β-d-allopyranosyl-5β,19-epoxycucurbitane-6,24-diene triterpene (charantoside XV, 6) along with 25ξ-isopropenylchole-5(6)-ene-3-O-β-d-glucopyranoside (1), karaviloside VI (2), karaviloside VIII (3), momordicoside L (4), momordicoside A (5) and kuguaglycoside C (7) from an Indian cultivar of Momordica charantia. At 50 µM compounds, 2–6 differentially affected the expression of pro-inflammatory markers IL-6, TNF-α, and iNOS, and mitochondrial marker COX-2. Compounds tested for the inhibition of α-amylase and α-glucosidase enzymes at 0.87 mM and 1.33 mM, respectively. Compounds showed similar α-amylase inhibitory activity than acarbose (0.13 mM) of control (68.0–76.6%). Karaviloside VIII (56.5%) was the most active compound in the α-glucosidase assay, followed by karaviloside VI (40.3%), while momordicoside L (23.7%), A (33.5%), and charantoside XV (23.9%) were the least active compounds. To better understand the mode of binding of cucurbitane-triterpenes to these enzymes, in silico docking of the isolated compounds was evaluated with α-amylase and α-glucosidase. 相似文献
49.
Satish M. Annigeri M. P. Sathisha Vidyanand K. Revankar 《Transition Metal Chemistry》2007,32(1):81-87
Binuclear cobalt(II), nickel(II), copper(II) and zinc(II) complexes of general composition [M2L1-2(μ-Cl)Cl2] · nH2O with the Schiff-base ligands (where L1H and L2H are the potential pentadentate ligands derived by condensing 2,6-diformyl-4-methylphenol with 4-amino-3-antipyrine and 2-hydroxy-3-hydrazinoquinoxiline,
respectively) have been synthesized and characterized. Analytical and spectral studies support the above formulation. 1H-NMR and IR spectra of the complexes suggest they have an endogenous phenoxide bridge, with chloride as the exogenous bridge
atom. The electronic spectra of all the complexes are well characterized by broad d–d and a high intensity charge-transfer
transitions. The complexes are chloro-bridged as evidenced by two intense far-IR bands centered around 270–280 cm−1. Magnetic susceptibility measurements show that complexes are antiferromagnetic in nature. The compounds show significant
growth inhibitory activity against fungi Aspergillus niger and Candida albicans and moderate activity against bacteria Bacillus cirroflagellosus and Pseudomonas auresenosa. 相似文献
50.