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1.
对UO2-Cd2O3可燃毒物芯块密度的影响因素进行了详细研究。试验表明:烧结时间、烧结温度、生坯密度、Gadox(含Gd的U3O8)、A.O(草酸铵)等条件与UO2-Gd2O3芯块密度存在一定关系。 相似文献
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3.
NanoSolve--一种包裹亲油性活性物的新技术 总被引:1,自引:0,他引:1
说明厂磷脂是天然化妆品成分,指出传统加溶方式的缺点,介绍了一种用磷脂包裹亲油性活性物的新技术、NanoSolve的原理和优点及其在护肤品等领域的应用。 相似文献
4.
Schistosome adults attract each other in vitro and the attraction is chemically mediated. InSchistosoma mansoni adults, excretory-secretory (ES) products of worms of one sex attract worms of the opposite sex, and at least the lipophilic fraction is attractive. Intra- and interspecific attraction occurs inSchistosoma mansoni, S. japonicum, andS. haematobium adults. Current knowledge of schistosome behavior in vitro is reviewed. 相似文献
5.
针对海洋水产品腹泻性毒素检测问题,设计了一种新型的基于细胞阻抗传感器(ECIS)的毒素快速检测分析系统。相对于传统的毒素检测方法,该系统具有操作简便,高一致性和高通量等特点。介绍了系统的硬件设计和软件设计,通过对系统整体性能测试以及使用神经母细胞瘤细胞(Neuro-2a)对腹泻性贝毒(DSP)大田软海绵酸(OA)进行毒性检测实验,用以验证系统平台的可行性。实验结果表明,基于细胞传感器的海洋水产品腹泻性毒性检测系统具备快速,长期,无损和高通量测量的特点,为腹泻性毒素检测提供了新的平台。 相似文献
6.
John I. Glendinning 《Journal of chemical ecology》1992,18(9):1559-1575
I compared the feeding responses of five species ofPeromyscus mice (aztecus, polionotus, melanotis, leucopus, andmaniculatus) to three bitter-tasting cardenolides (ouabain, digoxin, and digitoxin) that differ greatly in lipophilic character.Peromyscus, like other muroid rodents, are unusual in that they can ingest relatively large amounts of cardenolides without adverse physiologic effects. In experiment 1, I determined avoidance thresholds for the three cardenolides with 48 hr, two-choice tests. Mice exhibited large interspecific differences in avoidance threshold, and the interspecific ranking of the thresholds (maniculatus=leucopus >melanotis >polionotus >aztecus) was the same for each of the cardenolides. In experiment 2, I reevaluated the avoidance thresholds, but this time monitored the pattern of intake (i.e., bout lengths) during initial feeding encounters with cardenolidelaced diets. For each cardenolide, mice were subjected to three tests. In test 1, they received a control diet; in test 2, a diet containing the cardenolide at a concentration 1 log, unit below the avoidance threshold (as determined in experiment 1); and in test 3, a diet containing the cardenolide at the avoidance threshold concentration. Results were similar across all species and cardenolide types: Bout lengths in tests 1 and 2 were statistically equal, whereas those in test 3 were significantly shorter than those in test 1. The rapid rejection of cardenolide-laced diets in test 3 is consistent with a preingestive (i.e., gustatory) mechanism underlying the avoidance thresholds. I conclude (1) thatPeromyscus species differ substantially in taste sensitivity to cardenolides and that these differences may influence each species' respective ability to eat cardenolide-laced insects; and (2) that a species' relative taste sensitivity to one cardenolide predicts its sensitivity to other cardenolides. 相似文献
7.
在pH=5.2的HAc-NaAc缓冲液中,运用方波溶出伏安法同时测定贝类样品中的铅、镉离子。通过优化方波伏安检测条件,得到该检测方法的最佳参数:方波频率25Hz,方波振幅25mV,扫描速度4mV,沉积电位-1.1V,沉积时间120s。铅、镉离子分别在电位-0.571V与-0.743V附近产生灵敏的方波伏安溶出峰,在1×10-8-4×10-6mol/L范围内铅、镉离子的溶出峰电流与其物质的量浓度呈良好的线性关系,检出限分别为0.267μg/L,0.374μg/L,相关系数分别为0.9975,0.9995。该方法具有成本低廉、灵巧轻便、检测迅速等优势,可广泛应用于贝类等海产品的检测。 相似文献
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9.
It has been said that nuclear energy is an important option for especially developing countries to satisfy their increasing energy demand. However, it will be difficult to deploy first of a kind nuclear power plant in developing countries because extensive safety demonstration has to be conducted in industrialized countries. On the other hand, it will be essential to present rigid proof of reliable operational experience to develop proper understanding of the safety features of new reactor systems among the people around the demonstration plant sites. One of the ways to solve the issue is to integrate existing technologies supported by a great deal of data and experience into a new reactor design. Based on the consideration, a small-sized district heating reactor system based on the pressurized water reactor (PWR) technologies combined with the fuel concept of high temperature gas cooled reactors (HTGRs) has been studied. The purpose of the combination of these two existing concepts is to take the best advantages of both excellent operational experience of PWRs and the integrity of HTGR fuel, coated particle fuel, against fission products release even at high temperature. We expect that this approach will help create a breakthrough to the current stagnation of nuclear power deployment. 相似文献
10.
Marius Tchonang Pokaha Dawid E. Serfontein 《Journal of Nuclear Science and Technology》2018,55(8):843-849
In a previous study using a mixture of thorium and 20 a/o% LEU at 16 gram per fuel sphere heavy metal loading and adjusting the effective fuel enrichment to produce the same amount of cumulative energy per fuel sphere as with the 10 a/o% Low Enriched Uranium (LEU), the maximum Depressurized Loss Of Forced Cooling (DLOFC) temperature was reduced from 2273 to 1925 °C and 1811 °C for a symmetric and asymmetric core, respectively using an once-through-then-out (OTTO) fuelling scheme. This article presents an additional strategy for reducing the maximum DLOFC temperature by placing an optimized distribution of neutron poisons in the central reflector. This strategy produced maximum DLOFC temperatures of 1509 and 1448 °C for the symmetric and the asymmetric cores, respectively. These results are impressive as it means that the less complicated OTTO cycle with its lower capital cost achieved the same cumulative energy produced per fuel sphere than the standard six-pass refuelling scheme and that at substantially lower maximum DLOFC temperatures. Both the addition of the neutron poisons to the central reflector and the creation of a radially asymmetric core resulted in lower burn-ups that had to be reversed by increasing the enrichment of the fuel. 相似文献