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Similarly to but quite different from the xenon poisoning effects resulting from fission-produced iodine during the restart-up process of a fission reactor, we introduce a completely new concept of the tritium burn-up depth and tritium break-even time in the fusion energy research area. To show what the least required amount of tritium storage is used to start up a fusion reactor and how long a time the fusion reactor needs to be operated for achieving the tritium break-even during the initial start-up phase due to the finite tritium breeding time that is dependent on the tritium breeder, specific structure of breeding zone, layout of coolant flow pipe, tritium recovery scheme, extraction process, the tritium retention of reactor components, unrecoverable tritium fraction in breeder, leakage to the inertial gas container, and the natural decay etc., we describe this new phenomenon and answer this problem by setting up and by solving a set of equations, which express a dynamic subsystem model of the tritium inventory evolution in a fusion experimental breeder (FEB). It is found that the tritium burn-up depth is 317g and the tritium break-even time is approximately 240 full power days for FEB designed detail configuration and it is also found that after one-year operation, the tritium storage reaches 1.18kg that is more than the least required amount of tritium storage to start up three of FEB-like fusion reactors. 相似文献
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995.
Self-Organization of Topology and Weight Dynamics on Networks from Merging and Regeneration 总被引:1,自引:0,他引:1
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We propose a model of weighted networks in which the structural evolution is coupled with weight dynamics. Based on a simple merging and regeneration process, the model gives powel-law distributions of degree, strength and weight, as observed in many real networks. It should be emphasized that, in our model, the nontrivial degree-strength correlation can be reproduced and in agreement with empirical data. Moreover, the size-growing evolution model is also presented to meet the properties of real-world systems. 相似文献
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997.
JunBoWANG ChunHaoYANG XueMingYAN XiHartWU YuYuanXIE 《中国化学快报》2005,16(7):859-862
The novel bone-targeted agents were designed and synthesized by the combination of raloxifene and bisphosphonates. The anti-osteoporosis effect was evaluated by bone mineral density (BMD) obtained from OVX mice in vivo. The results indicated that the compound 8, 9 not only prevented ovariectomy induced loss of bone but also enhanced BMD to 0.87% and 19.67% compared to Sham, respectively. 相似文献
998.
该文讨论了带脉冲的Emden Fowler方程次线性奇异Dirichlet边值问题,利用上下解方法得到了该类问题正解存在的充分必要条件. 在脉冲的影响下得到了多解的存在性结果。 相似文献
999.
Kai Jun LIAO Xiao Hua YAN Dong Yun ZHAO Xue Yi MA* Department of Chemistry National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 《中国化学快报》2002,(3)
Lappaconitine (Figure 1) is a diterpenoid alkaloid, naturally occurring in roots and rhizomes of Aconitum and delphinium1. Lap reveals bradycardic and hypotensive activity2. But its application is restrained owing to its poor water solubility, toxicity and side effects on humans. In a number of pharmaceutical studies, b-CD has been reported to interact with many drug molecules to form inclusion complexes for improving the water solubility of drugs, and reducing their toxicity3. We have p… 相似文献
1000.
I.IntroductionInrecentyears,manyhomeandabroadscholarshavedoneagreatdealofstudiesontissuecharacterizationusingacousticparametersincludingultrasonicattenuationcoefficient,scatteringcoefficiellt,andnonlinearparameterB/Aofbiologicaltissue.Theseresearcheshavelearntmuchknowledgeoftheacousticpropertiesofsofttissue.Butbecauseofthedifferenceinresearchmethodsandtestingconditions,thediscrepa-nceofmeasuredresultsisstilllargeandnosteadycharacterizationmodelcanbeformed-Atthesametime,thestudyofrevealingthe… 相似文献