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81.
Tripathi V Navin A Mahata K Ramachandran K Chatterjee A Kailas S 《Physical review letters》2002,88(17):172701
Results for the cross section and average angular momentum for complete fusion at energies around the Coulomb barrier are presented for 7Li with 165Ho. Comparison of the cross sections with a one-dimensional barrier penetration model, using a potential consistent with the measured elastic scattering, showed a reduction above the barrier and an enhancement below it. An increase in the measured average angular momentum, , above the barrier and its consistency with that obtained from the fusion excitation function for weakly bound nuclei, is reported. These results together with a reanalysis of existing data conclusively demonstrate that the effect of breakup on fusion is coherent, like coupling to any nonelastic channel. 相似文献
82.
Background
The mechanism of aluminum-induced neurotoxicity is not clear. The involvement of glutamate in the aluminium-induced neurocomplications has been suggested. Brain glutamate levels also found to be altered in protein malnutrition. Alterations in glutamate levels as well as glutamate-α-decarboxylase in different regions of rat brain has been reported in response to aluminum exposure. Thus the study of glutamate metabolising enzymes in different brain regions of rats maintained on either normal or restricted protein diet may be of importance for understanding the neurotoxicity properties of aluminium. 相似文献83.
Preparation and properties of the following NiII and CuII complexes of the Schiff base derived from acetophenone and ethylenediamine (BAPE) and also of the mixed NiII and CuII chelates with BAPE and acetylacetone (acac-H) are described: In each case the Schiff base, BAPE, acts as a neutral bidentate ligand. The complexes are characterised by electronic spectra, magnetic susceptibilities, conductivities and elemental analyses. Pseudotetrahedral structure is proposed for M(BAPE)C12, while tetragonal structure for [M(BAPE)(acac)(H2O)2]ClO4 (M = Ni and Cu). The complex [Ni(BAPE) (acac)]ClO4 has been found to be square planar. 相似文献
84.
S. K. Chatterjee V. B. Agrawal 《Journal of polymer science. Part A, Polymer chemistry》1971,9(11):3225-3232
p-Aminobenzoic acid and formaldehyde were condensed in the presence of acid catalyst. The linear condensation polymer thus obtained was then separated into four fractions by a fractional precipitation method. Conductometric titrations were carried out on these four polymer fractions and the conglomerate in nonaqueous solvents with acid as well as base. The titration curves indicated a large number of additional breaks before the complete neutralization of COOH or NH2 groups. These observations have been interpreted in terms of degree of polymerization and the structure of the polymer. 相似文献
85.
86.
M. Spiteller-Friedmann R. Kaschnitz G. Spiteller A. Chatterjee N. Adityachaudhury G. Ganguli 《Monatshefte für Chemie / Chemical Monthly》1964,95(4-5):1228-1233
Rhazidin kann durch LiAlH4-Reduktion in Quebrachamin übergeführt werden. Für den basischen Bestandteil des Alkaloides ergibt sich daher Formel V. Umgekehrt ist die Verbindung V durch Oxydation von Quebrachamin mit Peressigsäure in guter Ausbeute zugänglich.
Mit 1 Abbildung 相似文献
Mit 1 Abbildung 相似文献
87.
We demonstrate a new technique for saturated-absorption spectroscopy by use of copropagating beams that does not have the problem of crossover resonances. The pump beam is locked to a transition, and its absorption signal is monitored while the probe beam is scanned. As the probe comes into resonance with another transition, the pump absorption is reduced and the signal shows a Doppler-free dip. We use this technique to measure hyperfine intervals in the D2 line of 85Rb with a precision of 70 kHz and to resolve hyperfine levels in the D2 line of 39K that are less than 10 MHz apart. 相似文献
88.
89.
90.
Immunomagnetic nanoparticle based quantitative PCR for rapid detection of Salmonella 总被引:1,自引:0,他引:1
Padmavathy Bakthavathsalam Vinoth Kumar Rajendran Uttara Saran Suvro Chatterjee Baquir Mohammed Jaffar Ali 《Mikrochimica acta》2013,180(13-14):1241-1248
We have developed a rapid and sensitive method for immunomagnetic separation (IMS) of Salmonella along with their real time detection via PCR. Silica-coated magnetic nanoparticles were functionalized with carboxy groups to which anti-Salmonella antibody raised against heat-inactivated whole cells of Salmonella were covalently attached. The immuno-captured target cells were detected in beverages like milk and lemon juice by multiplex PCR and real time PCR with a detection limit of 104 cfu.mL?1 and 103 cfu.mL?1, respectively. We demonstrate that IMS can be used for selective concentration of target bacteria from beverages for subsequent use in PCR detection. PCR also enables differentiation of Salmonella typhi and Salmonella paratyphi A using a set of four specific primers. In addition, IMS—PCR can be used as a screening tool in the food and beverage industry for the detection of Salmonella within 3–4 h which compares favorably to the time of several days that is needed in case of conventional detection based on culture and biochemical methods.
The method uses silica coated magnetic nanoparticles immobilized with anti-Salmonella antibody for immunomagnetic separation of Salmonella from beverages followed by detection by multiplex PCR (mPCR) and real time PCR (qPCR). This methodology contributes to rapid screening and accurate detection of Salmonella contaminations in beverages. 相似文献