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21.
Gurusamy Ramani Balasubramanian Meera Chinnathambi Vanitha Mala Rao Paramasamy Gunasekaran 《Applied biochemistry and biotechnology》2012,167(5):959-972
Penicillium funiculosum NCL1, a filamentous fungus, produced significantly higher levels of ??-glucosidase. The effect of initial pH, incubation temperature, and different carbon sources on extracellular ??-glucosidase production was studied in submerged fermentation. At 30?°C with initial pH 5.0, enzyme production was increased by 48-fold upon induction with paper mill waste, as compared to commercial cellulose powder. In zymogram analysis, four isoforms of ??-glucosidases were observed with wheat bran whereas a minimum of one isoform was observed with other carbon sources. A major ??-glucosidase (Bgl3A) with the apparent molecular weight of ~120?kDa, induced by paper mill waste, was purified 19-fold to homogeneity, with a specific activity of 1,796 U/mg. Bgl3A was a monomeric glycoprotein with 29% of neutral carbohydrate content. It showed optimum activity at pH 4.0 and 5.0, optimum temperature at 60?°C, and exhibited a half-life of 1?h at 60?°C. K m of Bgl3A was found to be 0.057?mM with p-nitrophenyl ??-d-glucoside and V max was 1,920 U/mg. The purified enzyme exhibited glucose tolerance with a K i of 1.5?mM. Bgl3A readily hydrolyzed glucosides with ??-linkage. Bgl3A activity was enhanced (156%) by Zn2+ and was not affected by other metal cations and reagents. The supplementation of Bgl3A (5 U/mg) with Trichoderma reesei cellulase complex (5 FPU/mg) resulted in about 70% of enhanced glucose production, which emphasizes the industrial importance of Bgl3A. 相似文献
22.
Gaffney Alexea M. Markov Sergei A. Gunasekaran M. 《Applied biochemistry and biotechnology》2001,91(1-9):185-193
The effectiveness of photosynthetic free-living and polyurethane foam (PU) immobilized Anabaena variabilis cells for, removal of orthophosphate (P) from water in batch cultures and in a photobioreactor was studied. Immobilization
in PU foams was found to have a positive effect on P uptake by cyanobacteria in batch cultures. The efficiency of P uptake
by immobilized cells was higher than by free-living cells. A laboratory scale photobioreactor was constructed for removal
of P from water by the immobilized cyanobacteria. The photobioreactor was designed so that the growth medium (water) from
a reservoir was pumped through a photobioreactor column with immobilized cyanobacteria and back to the reservoir. This created
a closed system in which it was possible to measure P uptake. No leakage of cells into the photobioreactor medium reservoir
was observed during the operation. The immobilized cells incorporated into a photobioreactor column removed P continuously
for about 15 d. No measurable uptake was demonstrated after this period. Orthophosphate uptake efficiency of 88–92% was achieved
by the photobioreactor. 相似文献
23.
Cadmium Magnesium Tetra Thiocyanate, CdMg(SCN)4, [CMTC] belongs to bimetallic thiocyanate complexes. CMTC crystals has been grown by solution growth technique at room temperature. The morphologies of the grown crystals are identified by single crystal analysis. Also the Powder X‐ray Diffractogram of the crystal has been recorded and the various planes of reflection are identified. The title compound crystallizes under triclinic structure with lattice parameters a = 10.0976 Å, b = 7.5015 Å, c = 5.7720 Å and β = 90.2135°. The presence of magnesium and cadmium in the grown crystals were confirmed through Atomic Absorption Spectroscopy. The grown crystals are analysed qualitatively by Fourier Transform Infrared (FTIR) and Fourier Transform Raman spectral measurements. The transmittance spectrum of the crystal in the UV‐Visible region has been recorded and analysed. The dielectric measurements for the crystals were carried out in the microwave region. The thermal stabilities of the crystals were studied by using different thermal analyses like Thermo Gravimetric Analysis (TGA), Differential Thermal Analysis (DTA) and Differential Scanning Calorimetry (DSC). (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
24.
K. Rameshbabu P. Kannan M. Gunasekaran P. Srinivasan R. Ramesh Babu R. Gopalakrishnan P. Ramasamy 《Crystal Research and Technology》2006,41(7):718-722
4,4′‐dihydroxy‐α‐methylstilbene (DHAMS) was synthesized by condensation reaction with chloroacetone and phenol in the presence of concentrated sulfuric acid, and has been successfully grown by solution growth technique. This is the first report in the literature on the crystallization of DHAMS and exhibited the birefringent melt (liquid crystal property) of the optical properties. FTIR and FTNMR studies are in accordance with the structure. Good quality crystals were grown by slow evaporation technique by acetone as solvent. A transmission spectrum of the crystal was obtained in the region of 285 nm. The structural and optical properties were studied. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
25.
S. Seshadri S. Gunasekaran S. Muthu S. Kumaresan R. Arunbalaji 《Journal of Raman spectroscopy : JRS》2007,38(11):1523-1531
The FT Raman and FTIR spectra of flucytosine were recorded in the region 3500–100 cm−1 and 4000–400 cm−1, respectively. The optimized geometry, wavenumber and intensity of the vibrational bands of flucytosine were obtained by ab initio and density functional theory (DFT) levels with complete relaxation in the potential energy surface using the 6‐31G(d,p) and 6‐311G(d,p) basis sets. A complete vibrational assignment aided by the theoretical harmonic frequency analysis is proposed. The harmonic vibrational wavenumbers calculated are compared with experimental FTIR and FT Raman spectra. The observed and the calculated wavenumbers are found to be in good agreement. The experimental spectra also coincide satisfactorily with those of theoretically constructed bar‐type spectrograms. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
26.
A Gunasekaran 《The Journal of the Operational Research Society》1998,49(7):758-765
Concurrent Engineering (CE) is a systematic approach to the integrated, simultaneous design of both products and their related processes, including production. A number of research reports are available in the literature to deal with CE and its applications in manufacturing industries. However, the application of CE in Process Industries (PI) has not received enough attention from researchers and practitioners for improving productivity and quality. To use CE effectively in process industries requires accuracy of data and a common architecture. In PI, the products are processed with minimal interruptions in any one production run or between production runs of products that exhibit process characteristics, such as liquids, fibres, powders and gases. The general characteristics of this industry add value to materials by mixing, separating, forming, or chemical reactions. PI often initiate their flow with only a few raw materials and subsequently process a variety of blending and resplitting operations. Nevertheless, there are many common characteristics such as material and information flow between manufacturing and PI. This indicates the application areas of CE in PI and hence to improve the competitiveness of PI in terms of flexibility and responsiveness. An attempt has been made in this paper to study how CE can be utilized to design products, production system, and production planning and control (PPC) system for improving productivity and quality in PI. 相似文献
27.
Rajendran P Ashokkumar B Muthukrishnan J Gunasekaran P 《Applied biochemistry and biotechnology》2002,102(1-6):201-206
Chemical analysis of electroplating effluent revealed the presence of very high concentrations of nickel (393 ppm) in the
effluent. Bioassay was carried out to test the toxicity of nickel chloride to Aspergillus niger. In contrast to 50% conidial inhibition at 1.7 mM nickel, hyphal extension was affected even at a lower concentration (0.4 mM), suggesting that hyphae are more sensitive than conidia to nickel. An increase in nickel concentration resulted in a proportionate
decrease in the hyphal extension. Nickel (II)-resistant mutants of A. niger M1, M2, and M3, were obtained using direct selection, stepwise adaptation, and ultraviolet mutation techniques. Biosorption
of Ni (II) by the mutant M3 was 50% more than that of its parent strain. 相似文献
28.
29.
A Gunasekaran 《The Journal of the Operational Research Society》2000,51(5):640-641
30.