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121.
122.
R. Acharya K. K. Swain Amit Kumar Nicy Ajith R. Verma A. V. R. Reddy 《Journal of Radioanalytical and Nuclear Chemistry》2010,286(2):507-511
For standardization of k 0-based instrumental neutron activation analysis, k 0-factors for short-lived nuclides (half-lives—11 s to 37 min) of elements F, Se, Sc, Al, V, Ti, Cu, Ca, Mg, I, and Cl with respect to gold (197Au) were determined using pneumatic carrier facility (PCF) at CIRUS reactor of BARC, Mumbai. Characterization of PCF was carried out by cadmium-ratio method using Au and Zr. The experimental k 0-factors of the isotopes were found to be in good agreement with the recommended k 0-factors in most of the cases, as evident from the values of % error and U-score at 95% confidence level. The method was validated by determining concentrations of elements through their short-lived nuclides in one type of the synthetic multielement standards (SMELS-I) obtained from SCK-CEN, Belgium. The method was also applied for determination of concentrations of some of the elements in two reference materials of IAEA, SL-3, and SL-1. 相似文献
123.
Hydrogenated amorphous silicon carbon nitride (a-SiCN:H) thin films were deposited by hot wire chemical vapor deposition (HWCVD) using SiH4, CH4, NH3 and H2 as precursors. The effects of the H2 dilution on structural and chemical bonding of a-SiCN:H has been investigated by Raman and X-ray photoelectron spectroscopy (XPS). Increasing the H2 flow rate in the precursor gas more carbon is introduced into the a-SiCN:H network resulting in decrease of silicon content in the film from 41 at.% to 28.8 at.% and sp2 carbon cluster increases when H2 flow rate is increased from 0 to 20 sccm. 相似文献
124.
Adam V. Marsh Nathan J. Cheetham Dr. Mark Little Dr. Matthew Dyson Dr. Andrew J. P. White Dr. Peter Beavis Dr. Colin N. Warriner Dr. Anthony C. Swain Prof. Paul N. Stavrinou Prof. Martin Heeney 《Angewandte Chemie (International ed. in English)》2018,57(33):10640-10645
The synthesis of a highly twisted chrysene derivative incorporating two electron deficient o‐carboranyl groups is reported. The molecule exhibits a complex, excitation‐dependent photoluminescence, including aggregation‐induced emission (AIE) with good quantum efficiency and an exceptionally long singlet excited state lifetime. Through a combination of detailed optical studies and theoretical calculations, the excited state species are identified, including an unusual excimer induced by the presence of o‐carborane. This is the first time that o‐carborane has been shown to induce excimer formation ab initio, as well as the first observation of excimer emission by a chrysene‐based small molecule in solution. Bis‐o‐carboranyl chrysene is thus an initial member of a new family of o‐carboranyl phenacenes exhibiting a novel architecture for highly‐efficient multi‐luminescent fluorophores. 相似文献
125.
Polyvinyl acetate based strippable polymer has been developed for surface decontamination. Stainless steel, mild steel, polyvinyl
chloride and rubber have been selected as candidate materials for the radioactive decontamination studies. The ease of strippability
and homogeneity of the polymer coating has been studied using infrared spectrophotometer. Decontamination of used radioactive
respirator has been carried out and the peels obtained have been subjected to leaching and incineration studies. The infrared
spectrophotometric studies also have been counducted to study the interaction between polyvinyl acetate and ions, like cesium,
strontium and cobalt.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
126.
Bimal P. Singh Sanjaya K. Swain Shashi K. Dash Sarama Bhattacharjee 《Journal of Dispersion Science and Technology》2013,34(2):251-258
Dispersion stability of highly concentrated ceramic suspensions using different dispersants required for colloidal processing can be assessed by measuring capillary suction time (CST). A systematic evaluation of dispersibility characteristics of colloidal alumina suspension is reported in the presence of three commonly used dispersants, namely, Dispex N 100, Darvan C, and Aluminon by employing the CST technique. The correlation between dispersibility of ceramic suspension and capillary suction time has been established. It has been found that higher the CST value of a suspension, the greater is the stability of the suspension and viceversa. In this investigation, this technique is employed both to choose suitable dispersant and to characterize the suspension. It has been concluded that higher the dispersion ratio (DR) of a suspension above unity the better is the stability and the lower the DR value below unity, the better is the aggregation tendency of the suspension. Quantitative estimation of dispersibility of an aqueous suspension is reported in terms of dispersion ratio. The CST technique has been found to be very useful and suitable for obtaining information for assessing stability of ceramic suspensions and characterizing concentrated ceramic slurry. 相似文献
127.
John Swain 《The European Physical Journal C - Particles and Fields》2011,71(1):455-457
The final states for the processb??sy have been extensively discussed in the literature. Similarly-detailed analyses for the caseb??s gluon have not been performed. Generally this process is searched for in 2-body decays such as B0??K+ ?? ?. We present simple arguments to suggest that most of the time the quark-level process will give rise to final states with rather high multiplicities. Comments are made about the applicability of these results tob??d gluon and hadronicb??u decays. 相似文献
128.
Soy protein concentrate, a biodegradable renewable resource agricultural biopolymer, has been cross-linked with formaldehyde for better processing material. Thermogravimetric analysis of the biopolymer has been followed using a computer analysis method, Lotus package, developed by us for assigning the degradation mechanism. A number of equations have been used to evaluate the kinetic parameters. The mechanism of degradation of the biopolymer is explained on the basis of the kinetic parameters. 相似文献
129.
Prafulla K. Sahoo Pradeep K. Rana Nandalal Deb Sarkar Anusmita Sahoo Sarat K. Swain 《Journal of polymer science. Part A, Polymer chemistry》2003,41(17):2696-2703
Jute fiber (Corchorus capsularis, JRC‐321 variety), an environmentally and ecologically friendly product, was chemically modified by the cooking alkaline sulfite process to unbleached and bleached pulps, which were further modified via graft copolymerization with acrylamide monomer with a complex initiating system: CuSO4/glycine/KHSO5. The above samples were characterized and morphologically analyzed by IR, thermogravimetric analysis, differential scanning calorimetry, scanning electron microscopy, and X‐ray diffraction. The biodegradability and superabsorbency of the samples were also evaluated for their novel commercial importance as jute‐based superabsorbents. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2696–2703, 2003 相似文献
130.
Employing Maxwell’s equations as the field theory of the photon, quantum mechanical operators for spin, chirality, helicity, velocity, momentum, energy, and position are derived. The photon “Zitterbewegung” along helical paths is explored. The resulting non-commutative geometry of photon position and the quantum version of the Pythagorean theorem is discussed. The distance between two photons in a polarized beam of given helicity is shown to have a discrete spectrum. Such a spectrum should become manifest in measurements of two photon coincidence counts. The proposed experiment is briefly described. 相似文献