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82.
Mazzotti FJ Achkasova E Chauhan R Tulej M Radi PP Maier JP 《Physical chemistry chemical physics : PCCP》2008,10(1):136-141
Four-wave mixing techniques have been used for the measurement of electronic transitions of cold transient species generated in a supersonic slit-jet discharge expansion. The origin band of the d(3)Pi(g)-a(3)Pi(u) system of C(2) and A(2)Pi(3/2)-X[combining tilde](2)Pi(3/2) electronic transition of HC(4)S were recorded. A signal-to-noise ratio of 10(4) in the spectra was achieved, resulting in detection limits of 10(10) cm(-3) for these two molecules. Application of selective two-color resonant four-wave mixing is used for the spectral assignment utilizing the double-resonance nature of the method. The combination of these techniques with a slit source proves to be a sensitive approach for the detection of transient molecules in a molecular beam discharge. 相似文献
83.
The non-relativistic radial Schrödinger equation is analytically solved using asymptotic iteration method within the framework of a general interaction potential whose special cases are the Cornell and Cornell plus harmonic potentials. The energy eigenvalues expression is derived in three dimensional space, which is further used to calculate the mass spectra of cc, bb, bc, cs, bs and bq mesons. The obtained results of this work are in good agreement with experimental and other relativistic results and also improved in comparison with other non-relativistic recent studies. 相似文献
84.
Suma C. Pemmaraju Deepak Sharma Nivedita Singh Richa Panwar Swaranjit S. Cameotra Vikas Pruthi 《Applied biochemistry and biotechnology》2012,167(5):1119-1131
The indigenous microbial community utilizing aliphatic, aromatic, and polar components from the oily sludge as sole source of carbon and energy was selected from the soil samples of Ankleshwar, India for biosurfactant production. Evaluation of biosurfactant production was done using screening assays such as surface tension reduction, hemolytic activity, emulsification activity, drop-collapse assay, and cell surface hydrophobicity studies. Maximum biosurfactant (6.9?g/l) production was achieved after 5?days of growth from Bacillus subtilis DSVP23 which was identified by 16S RNA technique (NCBI GenBank accession no. EU679368). Composition of biosurfactant showed it to be lipopeptide in nature with 15.2% protein content and 18.0% lipid content. Functional group analysis was also done by using Fourier transform infrared spectroscopy which showed it to be a protein-bound lipid thereby imparting them special properties. Analysis by matrix-assisted laser desorption/ionization time-of-flight mass spectrometric and nuclear magnetic resonance revealed that the major constituents of lipopeptide are leucine and isoleucine. Gas chromatographic analysis data indicated that oily sludge components of chain length C12?CC30 and aromatic hydrocarbons were degraded effectively by B. subtilis DSVP23 after 5?days of incubation. These results collectively points toward the importance of B. subtilis DSVP23 as a potential candidate for bioremediation studies. 相似文献
85.
Rajesh Kumar Richa Nitin H. Andhare Amit Shard Dr. Arun K. Sinha 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(44):14798-14803
86.
T. Maiyalagan C. Mahendiran K. Chaitanya Richa Tyagi F. Nawaz Khan 《Research on Chemical Intermediates》2012,38(2):383-391
Poly (o-phenylenediamine) (PoPD) microrods were obtained by interfacial polymerization using ferric chloride as oxidant and without any template or functional dopant. Pt/PoPD nanocatalysts were prepared by the reduction of chloroplatinic acid with sodium borohydride, and the composite catalysts formed were characterized by X-ray diffraction and electrochemical methods. The nanocomposite of Pt/PoPD microrods has been explored for their electro-catalytic performance towards oxidation of methanol. The electro-catalytic activity of Pt/PoPD was found to be much higher (current density 1.96?mA/cm2 at 0.70?V) in comparison to Pt/Vulcan electrodes (the current density values of 1.56?mA/cm2 at 0.71?V) which may be attributed to the microrod morphology of PoPD that facilitate the effective dispersion of Pt particles and easier access of methanol towards the catalytic sites. 相似文献
87.
During the aerosolization process at the sea surface, halides are incorporated into aerosol droplets, where they may play an important role in tropospheric ozone chemistry. Although this process may significantly contribute to the formation of reactive gas phase molecular halogens, little is known about the environmental factors that control how halides selectively accumulate at the air-water interface. In this study, the production of sea spray aerosol is simulated using electrospray ionization (ESI) of 100 nM equimolar solutions of NaCl, NaBr, NaI, NaNO(2), NaNO(3), NaClO(4), and NaIO(4). The microdroplets generated are analyzed by mass spectrometry to study the comparative enrichment of anions (f(X(-))) and their correlation with ion properties. Although no correlation exists between f(X(-)) and the limiting equivalent ionic conductivity, the correlation coefficient of the linear fit with the size of the anions R(X(-)), dehydration free-energy ΔG(dehyd), and polarizability α, follows the order: R(X(-))(-2) > R(X(-))(-1) > R(X(-)) > ΔG(dehyd) > α. The same pure physical process is observed in H(2)O and D(2)O. The factor f(X(-)) does not change with pH (6.8-8.6), counterion (Li(+), Na(+), K(+), and Cs(+)) substitution effects, or solvent polarity changes in methanol- and ethanol-water mixtures (0 ≤ x(H(2)O) ≤ 1). Sodium polysorbate 20 surfactant is used to modify the structure of the interface. Despite the observed enrichment of I(-) on the air-water interface of equimolar solutions, our results of seawater mimic samples agree with a model in which the interfacial composition is increasingly enriched in I(-) < Br(-) < Cl(-) over the oceanic boundary layer due to concentration effects in sea spray aerosol formation. 相似文献
88.
Kumar R Shard A Bharti R Thopate Y Sinha AK 《Angewandte Chemie (International ed. in English)》2012,51(11):2636-2639
All in one: a tandem strategy has been developed wherein secondary aryl alcohols are directly coupled with aryl halides to provide stilbenoids through a dehydrative Heck sequence in the ionic liquid [hmim]Br, and with water as a by-product under microwave irradiation. Classical methods do not permit this sequence to proceed in one pot, and some methods require multiple steps. hmim=1-n-hexyl-3-methylimidazolium. 相似文献
89.
A novel anthraquinonoidal calix[4]arene derivative was designed and synthesized for the preferential recognition of biologically important zinc in preference to prominently similar cadmium ions and other metal ions via quenching of fluorescence intensity. The stoichiometry of host guest complexation has been determined to be 1:1. The fluorescence changes associated with the recognition event may be attributed to the interaction of zinc ions with the nitrogenous functionality attached at the lower rim of calix[4]arene cavity which allows spatial disposition of the anthraquinonoid segments. 相似文献
90.
Gupta RK Trivedi R Awasthi R Paliwal VK Prasad KN Rathore RK 《Magnetic resonance imaging》2012,30(1):104-111
Diffusion tensor imaging (DTI) was performed on 25 patients with neurocysticercosis (NCC). The aim of this study was to investigate the changes in DTI measures during the evolutionary course of NCC lesions from vesicular to calcified stage in the brain. DTI measures were quantified from the NCC lesions of all patients. On the basis of conventional imaging findings, NCC lesions were classified into vesicular, vesicular colloidal, granular nodular and calcified stages. Significant inverse correlation was observed between the evolutionary stage of NCC lesion and mean diffusivity (MD; r=−0.748, P<0.001) and spherical anisotropy (CS; r=−0.585, P<.001) values. Significant direct correlations were observed between evolutionary stages of NCC lesion and mean fractional anisotropy (FA; r=0.575, P<0.001), linear anisotropy (CL; r=0.478, p<0.001) and planar anisotropy (CP; r=0.561, p<0.001) values. Successive decrease in MD values calculated from NCC lesions was observed, moving from vesicular to granular nodular stage. On FA, CL and CP maps, a significant increase in signal intensity value was observed in calcified as compared to other stages. We conclude that DTI measures may indicate the evolutionary changes in NCC from vesicular to calcified stage. 相似文献