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141.
Summary
N-benzamidosalicylaldimine (H2L) complexes of CuII, NiII, CoII, FeII, MnII. VOIV and TiOIV have been prepared. The ligand probably coordinates to the metal from the hydroxyl, carbonyl and imino groups. 相似文献
142.
In this paper, we propose a reliable algorithm to develop exact and approximate solutions for the linear and nonlinear Schrödinger equations. The approach rest mainly on two-dimensional differential transform method which is one of the approximate methods. The method can easily be applied to many linear and nonlinear problems and is capable of reducing the size of computational work. Exact solutions can also be achieved by the known forms of the series solutions. Several illustrative examples are given to demonstrate the effectiveness of the present method. 相似文献
143.
Ramu Rajasekaran Prakasarao Aruna Dornadula Koteeswaran Munusamy Baludavid Singaravelu Ganesan 《Journal of fluorescence》2014,24(4):1199-1205
Urine is one of the diagnostically potential bio fluids, as it contains many metabolites and some of them are native fluorophores. These fluorophores distribution and the physiochemical properties may vary during any metabolic change or at different pathologic conditions. Since urine is a multicomponent fluid, synchronous luminescence technique, a powerful tool has been adopted to analyse multicomponents in single spectrum and to resolve emission spectrum without much of photobleaching of fluorophores. In this study, urine samples of both normal subjects and cancer patients were characterised using synchronous luminescence spectroscopy with a Stokes shift of 20 nm. Different ratio parameters were calculated from the intensity values of the synchronous luminescence spectra and they were used as input variables for a multiple linear discriminant analysis across normal and cancer groups. The stepwise linear discriminant analysis classifies 90.3 % of the original grouped cases and 88.6 % of the cross-validated grouped cases correctly. 相似文献
144.
We classify the smallest two fold blocking sets with respect to the (n−k)-spaces in PG(n, 2). We show that they either consist of two disjoint k-dimensional subspaces or are equal to a (k + 1)-dimensional space minus one point. 相似文献
145.
The quantification of biofilm mechanical properties can serve as a basis for understanding biofilm resilience and for developing biofilm control strategies. One aspect of tensile testing that is likely to be important for a viscoelastic material such as bacterial biofilm, but unfortunately is often overlooked (i.e., not controlled or reported), is the strain rate used during testing. Thus, we performed tensile testing on intact S. epidermidis biofilms using the microcantilever method at 12 strain rate values ranging over approximately 3 orders of magnitude (0.013-9.07 s(-1)). Ultimate or cohesive strength, elastic modulus, and toughness increased with increasing strain rate and approached a plateau at approximately 1.3 s(-1). Failure strain, on the other hand, did not exhibit any trend with strain rate. Given that the mean values of some parameters increased by as much as 1 order of magnitude over the strain rate range used in this work, we suggest that the strain rate during tensile testing should be carefully controlled and reported to facilitate comparisons among different studies. Furthermore, the quantitative expressions developed in this work that relate mechanical property values with strain rate may be useful for modeling the deformation of bacterial biofilms under applied loads. 相似文献
146.
147.
Murudkar S Mora AK Singh PK Nath S 《Chemical communications (Cambridge, England)》2012,48(43):5301-5303
Structural changes in nucleic acids in the premelting region (T < melting temperature, T(m)) play an important role in the biological activity of DNA at physiological temperature. In the present communication we report the use of an ultrafast molecular rotor as an extrinsic fluorescence sensor to monitor the structural changes in natural DNA at T < T(m), which could not be detected even by circular dichroism spectroscopy. Further, the fluorescence sensor used in the present study is superior than most commonly used DNA stains. 相似文献
148.
Catherine J. Fletcher Daniel J. Blair Katherine M.P. Wheelhouse Varinder K. Aggarwal 《Tetrahedron》2012,68(37):7598-7604
A concise, highly enantioselective synthesis of sesquiterpene natural products (?)-debromoaplysin and (?)-aplysin has been completed. The key steps included lithiation–borylation of a secondary benzylic carbamate to give a tertiary boronic ester followed by propenylation which installed the quaternary stereocenter with complete enantioselectivity. Subsequent RCM followed by deprotection and in situ cyclization led to debromoaplysin with good diastereoselectivity from which the target compound was prepared in just eight overall steps. 相似文献
149.
Isotopic composition of uranium obtained from irradiated thorium dioxide was determined using alpha spectrometry by employing WinALPHA for the deconvolution of the alpha spectra recorded using electrodeposited sources. The results obtained were found to agree within 1% with those determined by thermal ionization mass spectrometry. The deconvolution methodology is important since it is possible to account for the in-growth of 228Th, which interferes in the determination of 232U by alpha spectrometry. The present methodology has the potential to determine isotopic composition of uranium in the irradiated thorium based nuclear fuels, employing alpha spectrometry. 相似文献