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21.
Ankita Bose Nandini Das Somendra N. Roy Nitesh Goswami Soumitra Kar R.C. Bindal P.K. Tewari 《International Journal of Hydrogen Energy》2014
An all silica DDR (deca dodecasil rhombohedral) zeolite membrane with dense, interlocked structure has been developed for separation of H2 from HI/I2 mixture of HI decomposition reaction. In this work, the DDR zeolite membrane was synthesized on the seeded clay-alumina substrate within 5 days. The seeds were synthesized by sonication mediated hydrothermal process within short crystallization time which enhanced the nucleation for the membrane growth. The synthesized membranes along with seed crystals were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR), Field emission scanning electron microscope (FESEM) and energy dispersive X-ray spectroscopy (EDAX). The selectivity of hydrogen with respect to CO2 and Ar was evaluated by single gas permeation studies at room temperature. The tests for corrosion resistance were carried out upto 120 h with both support and DDR membrane at 130 °C which confirmed the stability of membrane under the harsh HI/I2 environment. 相似文献
22.
Rajesh B. Gujar Parveen K. Verma Bholanath Mahanty Seraj A. Ansari Dibakar Goswami 《分离科学与技术》2020,55(14):2560-2569
ABSTRACT Solvent extraction studies were performed to understand the extraction behavior of Np4+ and NpO2 2+ from acidic feeds with CMPO (octyl (phenyl)-N,N-diisobutyl carbamoyl methyl phosphine oxide) dissolved in 1-butyl-3-methylimidazolium bis(trifluoromethane sulfonyl)imide, a water immiscible ionic liquid. Slope analyses on the distribution data revealed the extraction of ML2 type species, where M = Np4+ or NpO2 2+, and L = CMPO. Studies were also carried out with Pu4+ and UO2 2+ under identical conditions. The nature of the extracted species was found to vary with the nature of the ionic species. 相似文献
23.
Two dimensional transport characteristics of surface stabilized zero-valent iron nanoparticles in porous media 总被引:2,自引:0,他引:2
Kanel SR Goswami RR Clement TP Barnett MO Zhao D 《Environmental science & technology》2008,42(3):896-900
Zero-valent iron nanoparticles (INP) were synthesized and stabilized using poly acrylic acid (PAA) to yield stabilized INP (S-INP). A two-dimensional physical model was used to study the fate and transport of the INP and S-INP in porous media under saturated, steady-state flow conditions. Transport data for a nonreactive tracer, INP, and S-INP were collected under similar flow conditions. The results show that unstabilized INP cannot be transported into groundwater systems. On the other hand, the S-INP can be transported like a tracer without significant retardation. However, the S-INP plume migrated downward as it moved horizontally in the physical model, indicating that small density gradients have significant influence on two-dimensional transport. The variable-density groundwater flow model SEAWAT was used to model the observed density-driven transport patterns. This is the first time a two-dimensional transport data set is reported for demonstrating the multidimensional transport characteristics of nanoparticles. The data shows the importance of density effects, which cannot be fully discerned using one-dimensional, column experiments. Finally, we also demonstrate that the numerical model SEAWAT can be used to predict the density-driven transport characteristics of S-INP in groundwater aquifers. 相似文献
24.
Lactobacillus is among the most important GRAS food lactic acid bacteria, with nearly 140 species at present, mostly of industrial importance. Being part of the natural flora of a range of food products like raw milk, fermented dairy products, fruits, vegetables, meat products they also serve as starters for a number of fermented food products either to enhance the quality or to add health benefits. These groups of economically important species are often alike in phenotypic and physiological characteristics, probably due to their co-evolution in the same ecological niches; hence they are difficult to be differentiated. This demands advanced methods for their proper identification and characterization. With the advancement of molecular biology, a range of DNA-based molecular techniques has replaced the largely cumbersome phenotypic methods. This review summarizes the various molecular techniques available for detection and identification within the genus Lactobacillus, with special emphasis on the four groups of closely resembling species: L. casei group, L. acidophilus group, L. delbrueckii subspecies, and L. plantarum group. This review also provides insights into current trends for alternative molecular markers other than 16S rRNA to resolve the ambiguity within phylogenetically close species in the genus Lactobacillus. 相似文献
25.
G.C. Mahata A. Goswami D.K. Gupta 《Computers & Mathematics with Applications》2005,50(10-12):1767-1790
This paper investigates a group of computing schemas for joint economic lot size as fuzzy values of the economic lot size model for purchaser and vendor. We express the fuzzy order quantity/production lot size for the purchaser/vendor as the normal triangular fuzzy number (q1, q0, q2) and then we solve the aforementioned optimization problem under the condition 0 < q1 < q0 < q2. We find that, after defuzzification, the joint total relevant cost is slightly higher than in the crisp model. 相似文献
26.
S. C. Sabharwal Sangeeta Madhumita Goswami S. K. Kulkarni B. D. Padalia 《Journal of Materials Science: Materials in Electronics》2000,11(4):325-329
Beta barium borate (-BBO) crystals have been grown by the top seeded solution growth technique (TSSG) using Na2O as a flux. The crystals exhibited high transparency and the absence of inclusions and found to have sodium contamination in the range 150 to 230 p.p.m. The effect of this contamination on some crystal properties of interest has been investigated. The presence of impurities causes optical absorption below 550 nm in BBO crystals of both and -phases. X-ray photo emission spectroscopy (XPS) measurements performed on these crystals show that sodium gives rise to a measurable shift in the binding energies of the constituent ions. Further, the results show that Na+ ions enter into the lattice substitutionally and provide charge trapping sites close to the band edge. 相似文献
27.
Human glioblastoma multiforme cell lines, brain tumor biopsy tissue, and normal human fetal brain synthesize interleukin (IL)-6 and IL-6 receptor (IL-6R). Neither of these is expressed in human neurons or neuroblastoma cell lines in culture. Astrocytes from fetal brain grown in culture retain the ability to synthesize IL-6 but do not express IL-6R as inferred from RT-PCR and Southern blot studies. Coexpression of IL-6 and IL-6R in the glioblastoma cell line U87MG is confirmed by immunofluorescence staining. Both specific monoclonal antibodies against IL-6 and IL-6R and antisense oligonucleotide to IL-6 mRNA inhibit the growth of U87MG cells in culture, suggesting the existence of a functional autocrine growth loop. Anti-IL-6 antibodies also inhibit the growth of glioblastoma cell lines U373 and U118. The expression of IL-6 by human fetal astrocytes in culture is highly suggestive of its role as an oncofetal protein responsible for rapid proliferation of fetal and tumor cells but not cells of adult brain. 相似文献
28.
American document design process models reflect the assumption that comprehension and usability are the most important characteristics of effective documents, but it is increasingly evident that other cultures value other communicative features of documents and that purposes and intentions vary across cultures. This case study examines the responses of four sets of American readers (three sets familiar with American document design research and practice and one set of content specialists-engineers by training) to the visual aspects of an annual report. The original document was prepared for a mid-sized Japanese corporation and published and distributed in Japan; the American version is an almost literal translation of the original document from Japanese to English, with no changes in visuals, graphic design or format. Protocol analyses of readers' responses revealed distinct patterns of expectations and preferences based on (1) cultural biases, (2) degree of familiarity with the American document design model, and (3) ignorance of Japanese culture and corporate communicative practices. This study raises questions about the effectiveness in terms of cultural sensitivity of what we have called the “American” document design process model and usability testing procedures, and calls for extensive collaborative research designed to describe and analyze current practice in international settings 相似文献
29.
Bachan S. Rawat Amar N. Goswami Sri Krishna 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1980,30(1):557-562
Isobaric vapour-liquid equilibria for the ternary system hexane-benezene-sulpholane have been determined at 760 mmHg pressure. The data have been compared with those calculated using the NRTL equation. The NRTL constants obtained from the literature were evaluated from ternary liquid-liquid equilibrium data for this system. The agreement between experimental and calculated values is reasonable. 相似文献
30.
J. Pal S. Ghosh M. C. Goswami D. P. Singh Manoj Kumar R. K. Minj A. K. Upadhyay 《国际钢铁研究》2007,78(8):588-594
Electric arc furnace steel contains about 70‐120 ppm nitrogen. There is no suitable method for nitrogen removal from electric arc furnace steel up to the level desired for good quality bars and flat rolled products (30 ppm max). The existing process based on vacuum degassing can remove only up to 20% of nitrogen in steel. In the present study DRI fines have been injected into a steel bath which can drift out nitrogen in steel through production of fine CO bubbles in‐situ on reaction with residual FeO in DRI fines and C in bath. For high and medium carbon steel, nitrogen got reduced to 30 ppm and 60 ppm respectively where initial nitrogen was 150 – 200 ppm in steel. Nitrogen removal also depends upon bath depth and addition level of DRI. 相似文献