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1.
In solid state fermentation, Pleurotus sajor-caju has been found to be able to degrade at least 30% oil palm empty Fruit Bunch (EFB) fibre leaving 70 % useful materials. Conditions under which fermentation carried out were investigated. It was found that, in the temperature range between 25– 28 °C, relative ph between 6–8, moisture between 60–70 % and medium composition of CaCO3: rice bran 2 %: 5 % were the optimum conditions. The results showed in fermented products that, there were substantial reduction in cellulosic component such as Crude Fiber (CF, 18 %); Acid Detergent Fibre (ADF, 45 %), Neutral Detergent Fibre (NDF, 61 %) and Acid Detergent Lignin (ADL, 14 %). However, Crude Protein (CP, 10%) increased resulted from single cell protein enrichment of mycelial microbial mass. The mass reductions of substrate in fermentation process corresponds to the CO2 released during fermentation. Hence, attributable to the decreased in content of CF, ADF, NDF, and ADL. The digestibility study has also been carried out to determine the useful level of this product to ruminant. Aflatoxin content was detected low in both the initial substrates and products. Based on nutritional value and low content of aflatoxin, the product is useful as a source of roughage to ruminant.  相似文献   
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Optimality conditions are derived for a nonliear program in which a support function appears in the objective as well as in each constraint function. Wolfe and Mond-Weir type duals to this program are presented and various dualityresults are established under suitable convexity and generalized convexity assumptions. Special cases that often occur in the literature are those in which a support function is the square root of a positive semidefinite quadratic form or anLp norm. It is pointed out that these special cases can easily be generated from our results.  相似文献   
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A capillary GC method employing an internal standard has been developed and successfully used for quantitative determination both of the raw materials used for the manufacture of m-phenoxybenzaldehyde and for the components of the reaction mixtures obtained at various stages of the development of the process. A complete analysis can be performed in a single temperature programmed run.  相似文献   
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The capability of inductively coupled plasma mass spectrometry in determining trace levels of As, Se, and Sb in cloud water was evaluated. Preliminary studies focused on identifying and eliminating potential interferences in the cloud water matrix, the choice of appropriate internal standards, and system optimization. The detection limits for As, Se, and Sb were 20, 100, 20 pg/mL using pneumatic nebulization, and 5, 25, 5 pg/mL, respectively, using ultrasonic nebulization with a precision of better than 5% RSD. The accuracy was demonstrated by the analysis of a NIST commercial reference material, SRM 1643d. In all cases, the results from ICP-MS analysis agreed within 4% of the certified values. Comparative analysis of cloud water samples obtained from a site downwind from large pollution sources (Whiteface Mountain, New York) and Changlagali Pakistan, a rural mountain peak, was carried out by hydride generation atomic absorption (HGAA) spectrometry. There was excellent agreement between the ICP-MS and HGAA results. Received: 31 July 1997 / Revised: 28 October 1997 / Accepted: 31 October 1997  相似文献   
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The collisional behaviour of electronically excited silicon atoms in the optically metastable 3p2(1D2) state (0.781 eV) is investigated by time-resolved resonance absorption in the ultraviolet. Si(3 1D2) was generated by the repetitive pulsed irradiation of SiCl4 at λ > 165 nm in a flow system, and monitored by attenuation of resonance radiation at λ = 288.16 nm (4s(1P01) ← ep2(1D2)) using signal averaging. Absolute second-order rate constants (kR, cm3 molecule?1 s?1, 300 K) are reported for the gases: H2[(8.1 ± 1.5) × 10?11], O2[(2.3 ± 0.4) × 10?11], He (? 10?15) and SiCl4 [(2.9 ± 0.4) × 10?10]. These results are compared with the analogous data reported hitherto for Si(33PJ) and Si(3 1S0). Those for H2 and O2 are discussed within the context of symmetry arguments on the nature of the potential surfaces involved using the weak spin orbit coupling approximation. Finally, pulsed stimulated emission operating on the transition Si(3P2)(1So → 1D2) (λ = 1.0995 μ) was not detected in high energy pulse experiments using a confocal cavity, despite the population inversion between Si(3 1S0 and Si(3 1D2) observed by resonance absorption following the photolysis of SiCl4.  相似文献   
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A microwave digestion method in a closed vessel was developed for the determination of trace metals in atmospheric aerosols using inductively coupled plasma mass spectrometry (ICP-MS). A recovery study for the elements V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Cd, Sb, and Pb was conducted using multi-elemental standard solutions, NIST 1633b Trace Elements in Coal Fly Ash, and NIST 1648 Urban Particulate Matter. A simple digestion method using only HNO3/H2O2 gave good recoveries (90%-108%) for all elements except Cr in SRM 1648, but yielded low recoveries for SRM 1633b. A more robust method using HNO3/H2O2/HF/H3BO3 yielded higher recoveries (82%-103%) for the lighter elements (V-Zn) in SRM 1633b, and improved the Cr recovery in SRM 1648, but decreased the Se recovery in both SRMs. A comparative analysis of aerosol samples obtained at a remote mountain location Nathiagali, Pakistan (2.5 km above mean sea level), and Mayville, New York, downwind from the highly industrialized Midwestern United States, was carried out using Instrumental Neutron Activation Analysis (INAA) for the elements Cr, Mn, Fe, Co, Zn, As, Se, and Sb. The simple digestion method yielded excellent agreement for Cr, Fe, Zn, As, Se, and Sb, with slopes of the ICP-MS vs. INAA regressions of 0.90-1.00 and R2 values of 0.96-1.00. The regressions for Mn and Co had slopes of 0.82 and 0.84 with R2 values of 0.83 and 0.82, respectively. Addition of HF/H3BO3 did not improve the correlation for any of the elements and degraded the precision somewhat. The technique provides sensitivity and accuracy for trace elements in relatively small aerosol samples used in atmospheric chemistry studies related to SO2 oxidation in cloud droplets. The ability to determine concentrations of a very large number of elements from a single analysis will permit source apportionment of various trace pollutants and hence strategies to control the sources of air pollution. This is particularly important as the health effects of particulate matter are increasingly recognized.  相似文献   
9.
The collisional behaviour of electronically excited silicon atoms in the 3p2(1S0) state, 1.909 eV above the 3p2(3P0) ground state, is investigated by time-resolved attenuation of atomic resonance radiation at λ = 390.53 nm (4s(1Po1)←3p2 (1S0)). The optically metastable Si(31S0) atoms were generated by the repetitive pulsed irradiation of SiCl4 and their decay monitored in the presence of added gases. Absolute quenching rate constants (kQ, cm3 molecule?1 s?1, 300 K) are reported for the following collision partners: He (?1.3 × 10?15), SiCl4 ((9.1 ± 1.4) × 10?11), O2 ((1.5 ± 0.2) × 10?11) and N2O ((4.3 ± 0.4) × 10?11). The results for O2 and N2O are compared with analogous data reported hitherto for Si(3p2(3PJ)) and with those for the other np2(1S0) states of the group IV atoms C, Ge, Sn and Pb. The rate data for the silicon atoms are considered in terms of the nature of the potential surfaces arising from symmetry arguments based on the weak spin orbit coupling approximation.  相似文献   
10.
The ultraviolet spectra of Na2 and K2 molecules have been investigated. These studies were made in absorption in the second order of a 3.4 m Ebert Spectrograph with a reciprocal dispersion of 2.6 Å/mm. A number of new bands in the spectra of both the molecules not previously reported have been observed. Computer methods have been used to calculate the term values and to evaluate molecular constants.  相似文献   
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