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81.
82.
Solanki Bal Amit Baran Sharangi Tarun Kumar Upadhyay Fahad Khan Pratibha Pandey Samra Siddiqui Mohd Saeed Hae-Jeung Lee Dharmendra K. Yadav 《Molecules (Basel, Switzerland)》2022,27(19)
Worldwide, since ages and nowadays, traditional medicine is well known, owing to its biodiversity, which immensely contributed to the advancement and development of complementary and alternative medicines. There is a wide range of spices, herbs, and trees known for their medicinal uses. Chilli peppers, a vegetable cum spice crop, are bestowed with natural bioactive compounds, flavonoids, capsaicinoids, phytochemicals, phytonutrients, and pharmacologically active compounds with potential health benefits. Such compounds manifest their functionality over solo-treatment by operating in synergy and consortium. Co-action of these compounds and nutrients make them potentially effective against coagulation, obesity, diabetes, inflammation, dreadful diseases, such as cancer, and microbial diseases, alongside having good anti-oxidants with scavenging ability to free radicals and oxygen. In recent times, capsaicinoids especially capsaicin can ameliorate important viral diseases, such as SARS-CoV-2. In addition, capsaicin provides an ability to chilli peppers to ramify as topical agents in pain-relief and also benefitting man as a potential effective anesthetic agent. Such phytochemicals involved not only make them useful and a much economical substitute to wonder/artificial drugs but can be exploited as obscene drugs for the production of novel stuffs. The responsibility of the TRPV1 receptor in association with capsaicin in mitigating chronic diseases has also been justified in this study. Nonetheless, medicinal studies pertaining to consumption of chilli peppers are limited and demand confirmation of the findings from animal studies. In this artifact, an effort has been made to address in an accessible format the nutritional and biomedical perspectives of chilli pepper, which could precisely upgrade and enrich our pharmaceutical industries towards human well-being. 相似文献
83.
Muñoz MA Ferrero R Carmona C Balón M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2004,60(1-2):193-200
The NH-pi interactions of indole with benzene, naphthalene, phenanthrene, toluene, m-xylene, and mesitilene, in carbon tetrachloride solutions, have been studied by Fourier transform infrared spectroscopy. The experiments, carried out on the NH stretching band of indole, prove the formation of 1:1 complexes in which the NH bond of indole is engaged. The NH frequency shifts are independent of the number of rings in the base, but they progressively increase as the electron density is enhanced by methylation. The association constants increase with the increase of both, the number of rings and the methyl groups on the base. At higher base concentrations, further shifts on the free NH and associated bands indicate the formation of 1:2 complexes, which suggest hybride NH-pi and van der Waals interactions between one indole ring and two benzene acceptor molecules. 相似文献
84.
Dr. Christian Marquardt M. Sc. Tobias Kahoun Dr. Andreas Stauber Dr. Gábor Balázs Dr. Michael Bodensteiner Prof. Dr. Alexey Y. Timoshkin Prof. Dr. Manfred Scheer 《Angewandte Chemie (International ed. in English)》2016,55(47):14828-14832
We report on the synthesis and structural characterization of unprecedented anionic parent compounds of mixed Group 13/15 elements. The reactions of the pnictogenylboranes H2E‐BH2?NMe3 ( 1 a =P, 1 b =As) with phosphorus and arsenic centered nucleophiles of the type [EH2]? (E=P, As) lead to the formation of compounds of the type [H2E‐BH2‐E′H2]? ( 2 : E=E′=P; 3 : E=E′=As; 4 : E=P, E′=As) containing anionic pnictogen–boron chain‐like units. Furthermore, a longer 5‐membered chain species [H2As‐BH2‐PH2‐BH2‐AsH2]? ( 5 ) and a cyclic compound [NHCdipp‐H2B‐PH2‐BH2‐NHCdipp]+[P5B5H19]? ( 6 ) containing a n‐butylcyclohexane‐like anion were obtained. All the compounds have been characterized by X‐ray structure analysis, multinuclear NMR spectroscopy, IR spectroscopy, and mass spectrometry. DFT calculations elucidate their high thermodynamic stability, the charge distribution, and give insight into the reaction pathway. 相似文献
85.
The contamination of subsurface due to the chlorinated solvents such as tetrachlorethylene (PCE) and trichlorethylene (TCE)
is one of the most difficult environmental problems to treat. Bioremediation has been shown by many researchers to be a remedial
alternative for this type of contamination. Chlorinated solvents are not directly mineralized but rather are transformed by
microorganisms into one or more intermediate compounds before converting into a final compound. These sequential reactions,
termed “reductive dehalogenation”, consist of replacing a chlorine atom by a hydrogen atom. The pathway of degradation of
PCE can be expressed by the following scheme
PCE → TCE → DCE → VC → ETH,
where dichloroethene (DCE), vinyl chloride (VC) and finally ETH is ethylene.
Since the biotransformation rate coefficients of each intermediate compound are different, they have to be determined very
precisely to establish an effective treatment operation. The sequential decay can be described by Michaelis–Menten’s kinetics,
which constitutes a highly nonlinear system of ordinary differential equations (ODEs). This is very sensitive to the changes
of biotransformation rate coefficients.
In this study we introduce a methodology how to numerically estimate the rate coefficients for Michaelis–Menten’s equations
from the knowledge of the concentrations of PCE, TCE, DCE, VC and ETH. The efficiency of the proposed method is demonstrated
on some examples. Estimated biotransformation coefficients are employed to predict the concentrations of chlorinated solvents.
Computations and measurements show a very good agreement. 相似文献
86.
Uranium(VI) is adsorbed as a uranium trifluoroethylxanthate (TFEX)-cetyltrimethylammonium (CTMA) ion-pair complex on microcrystalline naphthalene quantitatively in the pH range 4.2 - 7.0. Without cetyltrimethylammonium as the counter ion, the adsorption is hardly 70%. The metal has been desorbed with HCI and determined with a differential pulse polarograph. Uranium can alternatively be quantitatively adsorbed on TFEX-CTMA-naphthalene adsorbent packed in a column at a flow rate of 1 - 5 ml/min and determined similarly. A well-defined peak has been obtained in this medium at -0.20 V versus a saturated calomel electrode. Cyclic voltammetry, differential pulse polarography and D.C. polarography studies indicate that uranium has been reduced irreversibly under these conditions. The detection limit is 0.30 microg/ml at the minimum instrumental settings (signal-to-noise ratio of 2) (with a preconcentration factor of 10, the detection limit would be 30 ng/ml for uranium when the volume in the cell is 15 ml). However if the volume in the cell is 5 ml, it would have been 10 ng/ml with a preconcentration factor of 30. Linearity is maintained in a concentration range of 0.5 - 19.0 microg/ml (2.1 - 79.83 x 10(-9) M) with a correlation factor of 0.9994 and a relative standard deviation of +/-1.1% (in this case 7.5 microg may be concentrated from 150 ml of the aqueous sample where its concentration is as low as 50 ng/ml). Various parameters, such as the effect of the pH, volume of the aqueous phase, flow rate and the interference of a large number of metal ions and anions on the determination of uranium, have been studied in detail to optimize the conditions for its trace determination in various complex materials, like alloys, coal fly ash, biological, synthetic, and waste-water samples. 相似文献
87.
88.
Louis A.P. Balázs 《Physics letters. [Part B]》1977,71(1):216-218
A simple planar cluster-multiperipheral model with a finite-energy sum rule constraint is set up, and self-consistency is imposed. This dynamically generates a zero-parameter infinitely-rising vector-tensor Regge trajectory which is in good agreement with experiment. 相似文献
89.
Bal.K. Agrawal 《Solid State Communications》1981,37(3):271-274
A five-atom cluster Bethe lattice method treating the short-range order with proper statistical effects has been proposed for understanding the crystalline and amorphous alloys. Numerical results for Ge1?xSix alloys are in excellent agreement with the experimental data. In the system studied the network is random but the nearest-neighbour coordination should be treated exactly. The long-range coordination is seen to be concentration-dependent in the crystalline alloys but concentration-independent in the amorphous alloys. 相似文献
90.
We have found a surfactant-promoted novel reductive synthesis of metallic Cu nanoclusters on metal oxides under hydrothermal synthesis conditions, which are active for the selective dehydrogenation of methanol. 相似文献