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1.
The redox reaction between the ferric complex of hydrophobic porphyrin and sodium dithionite in two different phases occurring at the interface between two immiscible liquids has been investigated by Volta potential measurements and spectroscopy. The reduction of the ferric complex of hydrophobic porphyrin adsorbed at the interface was found to be accompanied by a potential shift in the negative direction and to depend significantly on the nature of the anion and the ionic strength of the supporting electrolyte. Specifically adsorbed halogen anions inhibited the redox reaction in the sequence: Cl?, Br?, I?. Depending on pH, the ferric complex of hydrophobic porphyrin exists in the uncharged (FeP-O-PFe) form or in the cation FeP+ form. The interaction between the ferric complex hydrophobic porphyrin and water has also been investigated.  相似文献   
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Sphingolipids and glycolipids including previously unknown (2S,3S,4R)-1,3,4-trihydroxy-2-(2-(R)-hydroxyoctadecanoylamino)octadec-8E-ene, (2S,3R)-1,3-dihydroxy-2-octadecanoylamino-4E,8E-hexadecadiene, and (2-hydroxy-3-hexadecyloxypropyl)--L-fucopyranoside were isolated from soft corals collected on the shelf near the Andaman Islands (Indian Ocean). The structures of all compounds were established by spectroscopic methods and chemical analyses. The lipids possessed antibacterial activity against Bacillus subtilis, Bacillus pumilus, Escherichia coli, and Pseudomonas aeruginosa and antifungal activity against Aspergillus niger, Rhizopus oryzae, and Candida albicans.  相似文献   
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The multiplicity distribution for 11558 events in pp interactions at 22.4 GeVc was analyzed. The average charged multiplicity 〈nch〉 for inelastic events was found to be 4.69 ±0.05 and 〈nchD=2.04 ± 0.05. The early KNO scaling of normalized topological cross sections has been tested.  相似文献   
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We consider systems of homogenous polynomial equations of degreedin a projective space mover a finite field q. We attempt to determine the maximum possible number of solutions of such systems. The complete answer for the caser= 2,d<q− 1 is given, as well as new conjectures about the general case. We also prove a bound on the number of points of an algebraic set of given codimension and degree. We also discuss an application of our results to coding theory, namely to the problem of computing generalized Hamming weights forq-ary projective Reed–Muller codes.  相似文献   
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Partially hydrolyzed polyarbutin-containing benzoquinone groups were synthesized by using chemoenzymatic methods. This polymer was used as a mediator for the oxidation of pyrroloquinoline quinone-dependent glucose dehydrogenase. Polymer was covalently attached to the enzyme through the glucose moiety of the polymer and amine residues in the protein. Electrochemical studies show that the oxidized benzoquinone attached to the enzyme can act as a mediator for the reoxidation of the enzyme at carbon electrode surfaces. The apparent Michaelis constant and inactivation rate constant of the coupled enzyme were found to be similar to these parameters of the native enzyme.  相似文献   
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The 22.4 GeV/c \(\bar p\) p interactions with the leading particle and the slow proton subtracted are used as data on soft processes. Considerable similarity between them and hard processes, such ase + e ? annihilation into hadrons, is found by means of studying charged multiplicities, KNO scaling and longitudinal as well as transverse spectra.  相似文献   
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Paramagnetic copper(II) complexes with N-(3-hydroximino-2-methylbutan-2-yl)methylamine (HL), namely, Cu(HL)Cl2(I), Cu(HL)(SO4) · 2H2O (II), and Cu(HL)(NO3)2(III), were obtained. The crystal structures of I and II were determined. The blue crystals of these compounds are monoclinic. For I(C6H14Cl2CuN2O): a = 8.820(1) Å, b = 6.511(1) Å, c = 18.255(2) Å, = 92.86(1)° V = 1047.0(2) Å3, space group P21/c, calcd = 1.679 g/cm3, Z = 4 for R 1 = 0.0250; for II(C6H18CuN2O7S): a = 9.999(2) Å, b = 9.927(2) Å, c = 12.963(3) Å, = 106.37(3)°, V = 1234.5(4) Å3, space group P21/c, calcd = 1.753 g/cm3, Z = 4 for R 1 = 0.0324. Crystals of I have a molecular structure. The Cu coordination polyhedron is a square bipyramid (2N + 2Cl + Cl + Cl) due to additional contacts with two Cl atoms from the neighboring molecules. Structure II is built from polymeric chains. The environment of the Cu atom is a distorted cis-octahedron (2N + 2O(H2O) + 2O(SO4)). Complexes IIIIare characterized by IR and EPR spectroscopy.  相似文献   
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