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本文叙述过氧化钙的性质,并以实例说明过氧比钙在水产养殖、食品加上、果蔬保鲜。环境保护、农作物栽培、橡胶及化工等奋方面的应用。  相似文献   
3.
《Fusion Engineering and Design》2014,89(7-8):1195-1200
SYCOMORE, a fusion reactor system code based on a modular approach is under development at CEA. Within this framework, this paper describes the relevant sub-modules which have been implemented to model the main outputs of the breeding blanket and shield block of the system code: tritium breeding ratio, peak energy deposition in toroidal field coils, reactor layout and power deposition, blanket pressure drops and materials inventory.Blanket and shield requirements are calculated by several sub-modules: the blanket assembly and layout sub-module, the neutronic sub-module, the blanket design sub-module (thermal hydraulic and thermo-mechanic pre-design tool). A power flow module has also been developed which is directly linked to the blanket thermo-dynamic performances, which is not described in this paper.For the blanket assembly and layout and the blanket module design sub-modules, explicit analytic models have been developed and implemented; for the neutronic sub-module neural networks that replicate the results of appropriate simplified 1D and 2D neutronic simulations have been built. Presently, relevant model for the Helium Cooled Lithium Lead is available.Sub-modules have been built in a way that they can run separately or coupled into the breeding blanket and shield module in order to be integrated in SYCOMORE.In the paper, the objective and main input/output parameters of each sub-module are reported and relevant models discussed. The application to previous studied reactor models (PPCS model AB, DEMO-HCLL 2006–2007 studies) is also presented.  相似文献   
4.
The effective neutron multiplication factor (keff) as a function of burnup for different volume coolant (CoR) and fuel (FR) to cell ratio is presented. Additionally the Conversion Ratio (CR) of Th-232 to U-233, concentration of U-233, fissile and fission products calculation as a function of burnup are presented. The assembly is a critical reactor which makes volumes of coolant and fuel changes possible. In addition, an analytical model of calculation of keff as a function of U-233 and a poison concentration in equilibrium state are presented. One can achieve the criticality of Thorium Breeder Reactor (TBR) for enough high average neutron energy which one can obtain in Fast Breeder Reactor (FBR) only. The maximal value of CR and burnup for case of keff ≥ 1 achieves 1.4 and 360 GWd/MTU, correspondently. The calculations were done with a MCNPX 2.7 code using F2Be, Na and Pb coolants.  相似文献   
5.
From her early photographs of the ruinous aftermath of the Lebanon War in Beirut (1982) to her more recent images of bomb craters in Eleven Blowups (2006), the French artist Sophie Ristelhueber has been intent to maintain, in her own metaphor, ‘the analytical distance of an anatomy lesson’. Exhibiting the evidence of warfare but withholding their explanation, Ristelhueber’s provocative gesture of making art of war, removing human conflicts from their political contexts to render them as still-lifes, ready-mades, earthworks, or surrealist poems, is patently anti-journalistic. In keeping with the artist’s surgical analogy, this article explores Ristelhueber’s aesthetic mode of address as one that shares its fundamental operation with that of photography – namely, to make a cut. Retracing the morphology of recurring imprints and injuries that appear across the terrestrial and corporeal expanses traversed in her work, the article considers the ways in which these cuts pertain to the transformative power of violence and images alike.  相似文献   
6.
《Fusion Engineering and Design》2014,89(9-10):2088-2092
Three ITER equatorial port cells are dedicated to the assessment of six different designs of breeding blankets, known as Test Blanket Modules (TBMs). Several high temperature components and pipework will be present in each TBM port cell and will release a significant quantity of heat that has to be extracted in order to avoid the ambient air and concrete wall temperatures to exceed allowable limits. Moreover, from these components and pipes, a fraction of the contained tritium permeates and/or leaks into the port cell. This paper describes the optimization of the heat extraction management during operation, and the tritium concentration control required for entry into the port cell to proceed with the required maintenance operations after the plasma shutdown.  相似文献   
7.
We determined whether Allanblackia floribunda, a forest tree species that is valued for the fat extracted from its seeds, could be genetically improved for fruit/seed production by sampling 17–40 fruits from each of 70 trees that were distributed among four sites in wild stands. Fat was extracted from the seeds, and stearic and oleic acid content of the fat was estimated. Highly significant (P < 0.0001) between- and within-tree variation characterised fruits and seed characters. Between-site phenotypic variation was not significant. Stearic and oleic acid percentages in seed fat ranged from 44.16% to 66.12%, and from 24.95% to 48.42% per tree sample, respectively. Moderate repeatabilities were identified in fruit characters and mean seed mass. Moderate positive relationships were found between stearic and oleic acid percentages. Seed fat profiles were not found to vary with other fruit characters. Twenty “plus trees” were selected for breeding.  相似文献   
8.
高产酒精酵母菌种的选育   总被引:12,自引:1,他引:12  
从黄酒酒醅等样品中分离筛选并以热冲击处理,紫外线和Co^60-r射线照射获得一支高产酒精酵母种MHY4-36,以玉米淀粉为原料32℃发酵60-68h,可产酒精度17.5%(v/v)以上,耐酒精度20%(v/v )以上,并适合边糖化边发酵工艺。  相似文献   
9.
The aim of this study is to establish whether it is possible to select malting barley showing high quality under Australian conditions on the basis of malting quality data from the crop of the same genotype grown at a breeding station in Japan. Two approaches were taken to analyse the data obtained over several years. The first was a bivariate mixed model used to obtain variety estimates for the various quality traits of interest. The second approach used a univariate mixed model to determine the correlation between the same genotype grown in Australia and Japan, as well as the correlation between the same genotype grown at trial sites within a country. The first analysis found that nitrogen was related to most malting quality traits except for viscosity. The second analysis showed that the performance in Australia and Japan is similar for all malting quality traits. It may therefore be possible to select barley showing high malting quality under Australian conditions on the basis of malting quality data from the Japanese crop of the same genotype.  相似文献   
10.
通过多年来甜菜抗丛根病育种的实践与体会,概述了获得甜菜抗丛根病种质资源的手段与方法,筛选出了抗丛根病的甜菜新品系NC-7和NC-8及雄性不育系杂交组合NC203。在严重发病田其块根产量分别比感病品种甘糖1号增产403.1%、448.9%和562.5%;含糖率分别比甘糖1号增加79.9%,60.2%和29.2%。  相似文献   
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