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41.
The present study was carried out to evaluate the effects of ozone on rice grains for the following three conditions: saturation time, decay rate, and half-life of ozone. Experiments were performed in different bed thicknesses (5 and 10 cm) and moisture content (11.4 and 14.2% wb) at atmospheric conditions. The lowest saturation time of ozone was 119 min, with the concentration of 516 ppm for rice grains ozonated at 5-cm bed thickness with 11.4% (wb) moisture content. The decay rate kinetics of ozone obtained were consistent with a first-order model. Regarding the half-life of ozone, the lowest value obtained was 6.78 min for rice grains ozonated at 10-cm bed thickness with 14.2% (wb) moisture content.  相似文献   
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A high conversion light water reactor lattice has been analysed using the code DRAGON Version4. This analysis was performed to test the performance of the advanced self-shielding models incorporated in DRAGON Version4. The self-shielding models are broadly classified into two groups – “equivalence in dilution” and “subgroup approach”. Under the “equivalence in dilution” approach we have analysed the generalized Stamm’ler model with and without Nordheim model and Riemann integration. These models have been analysed also using the Livolant–Jeanpierre normalization. Under the “subgroup approach”, we have analysed Statistical self-shielding model based on physical probability tables and Ribon extended self-shielding model based on mathematical probability tables. This analysis will help in understanding the performance of advanced self-shielding models for a lattice that is tight and has a large fraction of fissions happening in the resonance region. The nuclear data for the analysis was generated in-house. NJOY99.90 was used for generating libraries in DRAGLIB format for analysis using DRAGON and A Compact ENDF libraries for analysis using MCNP5. The evaluated datafiles were chosen based on the recommendations of the IAEA Co-ordinated Research Project on the WIMS Library Update Project. The reference solution for the problem was obtained using Monte Carlo code MCNP5. It was found that the Ribon extended self-shielding model based on mathematical probability tables using correlation model performed better than all other models.  相似文献   
44.
The rapid accumulation of the p53 gene product is considered to be an important component of the cellular response to a variety of genotoxins. In order to gain insights on the biochemical pathways leading to p53 stabilization, the effect of (+/-) 7,8-dihydroxy-anti-9, 10-epoxy-7,8,9,10-tetrahydrobenzo(a)-pyrene [(+/-)-anti-BPDE] induced DNA damage on p53 protein levels was investigated in various repair-proficient and repair-deficient human cells. Brief exposure of normal human fibroblasts to 0.05-1 microM (+/-)-anti-BPDE resulted in elevated p53 protein levels as compared to the constitutive levels of control cells. The rapid induction response, detectable within a few hours, was sustained up to a period of at least 24 h. Repair-proficient and repair-deficient (XPA) human lymphoblastoid cells showed a similar response. The poly(ADP-ribose) polymerase inhibitor, 3-aminobenzamide (3-AB), diminished the p53 induction response by concomitantly decreasing the extent of (+/-)-anti-BPDE induced DNA damage in cells pretreated with the inhibitor. However, the direct involvement of poly ADP-ribosylation was also apparent as 3-AB was able to attenuate (approximately 50%) the p53 response by post-damage inhibitor treatment of the cells. Inhibition of cellular DNA replication by hydroxyurea and AraC, in the presence or absence of DNA damage, also resulted in rapid p53 accumulation in repair-deficient cells. On the contrary, inhibition of protein kinase C (PKC) by calphostin-C led to an abrogation of (+/-)-anti-BPDE mediated p53 induction. Analysis of the downstream effects of carcinogen treatment showed that the lymphoblastoid cells undergo DNA fragmentation indicative of apoptosis while fibroblasts exhibit cell cycle arrest at the G1-S boundary.  相似文献   
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Acid hydrolysis of horn meal (obtained from raw horns of slaughtered cattle and buffaloes) yields a mixture of water soluble and low molecular weight peptides with average particle size of 3,838 nm (3.84 μm) and mean intensity of 5,243.7 nm (5.24 μm) and mean volume of 6,228.1 nm (6.23 μm). These peptides on reaction with Cr(III) yield a product that exhibits high exhaustion of chromium bath (above 92%) during tanning of hides and skins. To consolidate the results, the process was up-scaled in Central Leather Research Institute (CLRI) pilot plant for commercial trials. This material is applied directly to the pickled pelts at 8% w/w level and then the pelt is converted to wet blues and crust leathers. Control leathers were also processed concurrently using standard chrome tanning salts (8% w/w). Leathers showed the desired level of softness, fullness, shrinkage temperature and physical properties, and are comparable with control ones. Our results have indicated the use of Cr(III)–keratin complex could considerably reduce pollution load of Cr salts in leather processing.  相似文献   
47.
A cobalt-base refractory alloy containing W, Ni, and Cr, which is widely used for making spacecraft components operating at high temperatures, is studied. Changes in the microstructure of the alloy are studied depending on the heat treatment, and the effect of these changes on mechanical properties at room and high temperatures is determined.  相似文献   
48.
The International Journal of Advanced Manufacturing Technology - This study attempts to incorporate SiC particles in the weld zone during friction stir welding of Al 6351 alloy. SiC particles of...  相似文献   
49.
A state variable block diagram method is given for the realization of universal biquadratic transfer functions employing second-generation current-controlled conveyors (CCCIIs). Using minimum number of passive components and properly adjusting the bias currents of CCCIIs, the proposed circuits can realize all the tunable frequency standard filter functions: high-pass, band-pass, low-pass, notch-pass, and all-pass by choosing appropriate input branches without changing the passive elements. These presented circuits are in current-mode and voltage-mode separately. The non-ideality analyses of these configurations are given. Additionally, a high-order low-pass filter derived from the proposed voltage-mode biquadratic filter is introduced. PSPICE simulation results are included to verify the theory.  相似文献   
50.
Mobile Networks and Applications - 5G/6G communication are first generation high speed wireless communication network which integrates the aerial data, terrestrial data and maritime data via...  相似文献   
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