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1.
Rathore Vikas Tiwari Budhi Sagar Nema Sudhir Kumar 《Plasma Chemistry and Plasma Processing》2022,42(1):109-129
Plasma Chemistry and Plasma Processing - The present study has been carried to investigate the interaction and effect of plasma activated water (PAW) on pea seeds. PAW is produced with the... 相似文献
2.
Ashish Goel Monika R. Henzinger Serge Plotkin Eva Tardos 《Journal of Algorithms in Cognition, Informatics and Logic》2003,48(2):314-332
In this paper we consider the online ftp problem. The goal is to service a sequence of file transfer requests given bandwidth constraints of the underlying communication network. The main result of the paper is a technique that leads to algorithms that optimize several natural metrics, such as max-stretch, total flow time, max flow time, and total completion time. In particular, we show how to achieve optimum total flow time and optimum max-stretch if we increase the capacity of the underlying network by a logarithmic factor. We show that the resource augmentation is necessary by proving polynomial lower bounds on the max-stretch and total flow time for the case where online and offline algorithms are using same-capacity edges. Moreover, we also give polylogarithmic lower bounds on the resource augmentation factor necessary in order to keep the total flow time and max-stretch within a constant factor of optimum. 相似文献
3.
We present a characterization of confluence for term rewriting systems, which is then refined for special classes of rewriting systems. The refined characterization is used to obtain a polynomial time algorithm for deciding the confluence of ground term rewrite systems. The same approach also shows the decidability of confluence for shallow and linear term rewriting systems. The decision procedure has a polynomial time complexity under the assumption that the maximum arity of a function symbol in the signature is a constant. 相似文献
4.
A triangulation of a connected closed surface is called weakly regular if the action of its automorphism group on its vertices
is transitive. A triangulation of a connected closed surface is called degree-regular if each of its vertices have the same
degree. Clearly, a weakly regular triangulation is degree-regular. In [8], Lutz has classified all the weakly regular triangulations
on at most 15 vertices. In [5], Datta and Nilakantan have classified all the degree-regular triangulations of closed surfaces
on at most 11 vertices.
In this article, we have proved that any degree-regular triangulation of the torus is weakly regular. We have shown that there
exists ann-vertex degree-regular triangulation of the Klein bottle if and only if n is a composite number ≥ 9. We have constructed two
distinctn-vertex weakly regular triangulations of the torus for eachn ≥ 12 and a (4m + 2)-vertex weakly regular triangulation of the Klein bottle for eachm ≥ 2. For 12 ≤n ≤ 15, we have classified all then-vertex degree-regular triangulations of the torus and the Klein bottle. There are exactly 19 such triangulations, 12 of which
are triangulations of the torus and remaining 7 are triangulations of the Klein bottle. Among the last 7, only one is weakly
regular. 相似文献
5.
Spectral data during a chelatometric titration were utilized for determining an equivalence point of the titration. Three-dimensional titration data were analyzed by fitting to a theoretical equation that was derived from equilibrium equations among a metal ion, an indicator and EDTA. The equation with optimized parameters successfully explained the three-dimensional titration data. This method was applied to EDTA titration systems of zinc, cadmium and lead with xylenol orange (XO) as an indicator. These systems were analyzed while taking the formation of 1:1 and 2:1 metal-indicator complexes into account. By this method, an accurate equivalence point was determined as well as stability constants and molar absorption spectra of metal-indicator complexes in each titration system. Moreover, the comparability among the concentrations of the metal standard solutions prepared from pure metals (Zn, Pb, and Cd) was also confirmed by the proposed evaluation method. 相似文献
6.
S. C. Tiwari 《Foundations of Physics Letters》2006,19(1):51-62
Advances in gauge theories and unified theories have not thrown light on the meaning of electron. The problem of the origin
of electronic charge is made precise, new insights gained from Weyl space are summarized, and the origin of charge in terms
of fractional spin is suggested. A new perspective on the abelian Chern-Simons theory is presented to explain charge. 相似文献
7.
8.
C. P. Painuli B. P. Bahuguna B. D. Indu M. D. Tiwari 《International Journal of Theoretical Physics》1992,31(1):81-108
The theory of first-, second-, and third-order Raman scattering is investigated for isotopically disordered anharmonic crystals. The theory of time-dependent thermodynamic Zubarev Green's functions is adopted to obtain the Raman tensor, intensity of Raman lines, and differential cross sections of various orders of scatterings. It is observed that each class of scattering can be separated into diagonal and nondiagonal parts. The first-order and nondiagonal parts are absent in the case of chemically pure crystals. The diagonal parts are separated into anharmonic and interference terms. The interference terms arise due to the interactions of anharmonic phonons with the local phonons. The temperature and defect dependencies are discussed in detail along with the nature of continuous and line spectra. It is proposed that very high-power laser sources will reveal the third-order spectra, and that the resulting structure can be explained with the help of temperature-dependent one-, two-, and three-phonon density of states. 相似文献
9.
It has been found that the states of the 2-charge extremal D1–D5 system are given by smooth geometries that have no singularity and no horizon individually, but a ‘horizon’ does arise after ‘coarse-graining’. To see how this concept extends to the 3-charge extremal system, we construct a perturbation on the D1–D5 geometry that carries one unit of momentum charge P. The perturbation is found to be regular everywhere and normalizable, so we conclude that at least this state of the 3-charge system behaves like the 2-charge states. The solution is constructed by matching (to several orders) solutions in the inner and outer regions of the geometry. We conjecture the general form of ‘hair’ expected for the 3-charge system, and the nature of the interior of black holes in general. 相似文献
10.
The analytical potential of water as an eluent in thin layer chromatographic separation of various anions on plain adsorbent layers (silica gel "G" alumina, and cellulose) as well as on beds containing different combinations of silica gel, alumina, or cellulose has been investigated. In addition to some important separation of anions, microgram separation of IO−4 from milligram quantities of IO−3, Bro−3, MoO2−4, and Fe (CN)3−6 has been realized. The effect on pH of the sample in the separation of IO−4 from accompanying ions has also been studied. The limits of detection and dilution limits of anions on alumina thin layers have been determined. NO−2 in artificial seawater has been detected. The effect of CaCl2, MgCl2, and NaHCO3 on some ternary separations of analytical importance has been examined. 相似文献