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31.
Latent damage tracks of energetic40Ar ions (18·56 MeV/u) have been recorded in Lexan polycarbonate detector. Bulk and track-etch parameters are evaluated under successive chemical
etching. Our results show a linear correlation between the measured track-etch rate along the track and the corresponding
total energy-loss rate and predict a threshold value of 5·0 MeV mg−1 cm2 for track registration. Maximum etchable track lengths of40Ar ions as a function of energies have also been measured and compared with three different sets of theoretical ranges. 相似文献
32.
The aggregation/deaggregation of chlorin p6 with the surfactants CTAB, SDS, and TX 100 have been studied by using absorption, fluorescence, and light scattering techniques. The ionic surfactants are found to cause aggregation of fluorophore at submicellar concentrations. The aggregates dissolve at higher surfactant concentrations to yield micellized monomers. This is rationalized by the interplay of electrostatic and hydrophobic effects. A prominent pH effect is observed in the ionic surfactant induced aggregation process as the charge on the fluorophore is controlled by the pH of the medium. Interestingly, the neutral TX-100 also induces aggregation of chlorin p6 at low concentrations, indicating that hydrophobic effects by themselves can cause aggregation unless there is a hindrance by repulsive electrostatic effects. 相似文献
33.
Jaya N. Iyer 《Compositio Mathematica》2003,136(3):317-321
In this paper, we show that the Chern classes c
k
of the de Rham bundle
defined on any good toroidal compactification
of the moduli space of Abelian varieties of dimension g are zero in the rational Chow ring of
, for g=4, 5 and k>0. 相似文献
34.
Jaya N. Iyer 《Transactions of the American Mathematical Society》2003,355(8):3209-3216
We show that ample line bundles on a -dimensional simple abelian variety , satisfying 2^g\cdot g!$">, give projective normal embeddings, for all .
35.
Various empirical theories of ultrasonic velocity have been applied to three binary liquid mixtures, under pressures up to
200 MPa and their validity have been tested. A pressure dependent study of ultrasonic velocities has been made at 303.15 K.
The agreement between theory and experiment is found to be quite satisfactory. 相似文献
36.
Jaya Ram Simkhada Seung Sik Cho Seong Ju Park Poonam Mander Yun Hee Choi Hyo Jeong Lee Jin Cheol Yoo 《Applied biochemistry and biotechnology》2010,162(5):1457-1470
Organic solvent- and detergent-resistant proteases are important from an industrial viewpoint. However, they have been less
frequently reported and only few of them are from actinomycetes. A metalloprotease from Streptomyces olivochromogenes (SOMP) was purified by ion exchange with Poros HQ and gel filtration with Sepharose CL-6B. Apparent molecular mass of the
enzyme was estimated to be 51 kDa by sodium dodecyl sulfate–polyacrylamide gel electrophoresis and gelatin zymography. The
activity was optimum at pH 7.5 and 50 °C and stable between pH 7.0 and 10.0. SOMP was stable below 45 °C and Ca2+ increased its thermostability. Ca2+ enhanced while Co2+, Cu2+, Zn2+, Mn2+, and Fe2+ inhibited the activity. Ethylenediaminetetraacetic acid and ethylene glycol-bis (β-aminoethyl ether)-N,N,N′,N′-tetraacetic acid, but not phenylmethylsulfonyl fluoride, aprotinin, and pefabloc SC, significantly suppressed the activity,
suggesting that it might be a metalloprotease. Importantly, it is highly resistant against various detergents, organic solvents,
and oxidizing agents, and the activity is enhanced by H2O2. The enzyme could be a novel protease based on its origin and peculiar biochemical properties. It may be useful in biotechnological
applications especially for organic solvent-based enzymatic synthesis. 相似文献
37.
C B Dwivedi 《Pramana》2000,55(5-6):849-854
Theoretical prediction of a new kind of normal mode behaviour of electro-mechanical nature was first time reported by Dwivedi
and Das in 1992 in the context of mesospheric modeling of observed neutral induced turbulence. Local dynamo action (due to
relative neutral flow) governs the basic physical principle for linear excitation of the neutral induced low frequency instability
(NILF) in mesospheric plasma, which comprises of weakly ionized inhomogeneous gas confined by the external gravity and ambient
magnetic field. The present contribution offers physical explanation in terms of dynamo transformation of neutral drag effect
as a source to understand complete suppression of the usual collisional R-T and in turn linear driving of the NILF. It is
therefore emphasized, worth calling it as the dynamo instability. 相似文献
38.
We study projective curvature tensor in K-contact and Sasakian manifolds. We prove that (1) if a K-contact manifold is quasi projectively flat then it is Einstein and (2) a K-contact manifold is ξ-projectively flat if and only if it is Einstein Sasakian. Necessary and sufficient conditions for a K-contact manifold to be quasi projectively flat and φ-projectively flat are obtained. We also prove that for a (2n + 1)-dimensional Sasakian manifold the conditions of being quasi projectively flat, φ-projectively flat and locally isometric to the unit sphere S
2n+1 (1) are equivalent. Finally, we prove that a compact φ-projectively flat K-contact manifold with regular contact vector field is a principal S
1-bundle over an almost Kaehler space of constant holomorphic sectional curvature 4. 相似文献
39.
40.
Bahl and Zionts [H.C. Bahl, S. Zionts, A noniterative multiproduct multiperiod production planning method, Operations Research Letters 1 (1982) 219-221] formulated a problem for planning multiproduct multiperiod production on a single facility. They developed a column-minima noniterative method and claimed that it gave an optimal solution. We show that the claim is incorrect. 相似文献