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71.
An updated version of the ITER Preliminary Safety Report has been produced and submitted to the licensing authorities. It is revised and expanded in response to requests from the authorities after their review of an earlier version in 2008, to reflect enhancements in ITER safety provisions through design changes, to incorporate new and improved safety analyses and to take into account other ITER design evolution. The updated analyses show that changes to the Tokamak cooling water system design have enhanced confinement and reduced potential radiological releases as well as removing decay heat with very high reliability. New and updated accident scenario analyses, together with fire and explosion risk analyses, have shown that design provisions are sufficient to minimize the likelihood of accidents and reduce potential consequences to a very low level. Taken together, the improvements provided a stronger demonstration of the very good safety performance of the ITER design.  相似文献   
72.
A technical dye of the anthraquinone type was analyzed by GPC, mass spectroscopy, and elemental analysis. Along with the polymerizable component, N-[4-amino-3-methoxyanthraquinonyl-(1)] methacrylamide (I), it contained a saturated admixture, N-[4-amino-3-methoxyanthraquinonyl-(1)]-2-chloro-2-methylpropionamide (II). The homopolymerization of I was carried out, and admixture II was isolated and characterized. The copolymerization of the dye with styrene and methyl methacrylate was verified, and the retardation effect of II on the polymerization of these monomers was evaluated.  相似文献   
73.
平锻机用于长杆类锻件局部多工位成形,可完成镦粗、冲孔、切边、镦挤、切断、弯曲等工作(图1)。平锻机一般有垂直分模式平锻机和水平模式平锻机两种。锻模分模方式给平锻机结构带来了明显的差别。垂直分模式平锻机在最近30~40年虽结构上变化不大,但耐用性逐步提高,表现在其自身的刚性、工艺适应性及能耗指标均有改善;水平分模式平锻机则相比之下仍处于研制和完善过程之中。1两种平锻机的比较(1)垂直分模式平锻机该类平锻机可靠性高,使用寿命长,工作区域操作方便,锻模更换容易,氧化皮易于从工作区域清理,提高了锻模的寿命。但该类平锻机难于…  相似文献   
74.
This paper considers unconditionally secure protocols for reliable broadcast among a set of n players, where up to t of the players can be corrupted by a (Byzantine) adversary but the remaining h = n - t players remain honest. In the standard model with a complete, synchronous network of bilateral authenticated communication channels among the players, broadcast is achievable if and only if 2n/h < 3. We show that, by extending this model by the existence of partial broadcast channels among subsets of b players, global broadcast can be achieved if and only if the number h of honest players satisfies 2n/h < b + 1. Achievability is demonstrated by protocols with communication and computation complexities polynomial in the size of the network, i.e., in the number of partial broadcast channels. A respective characterization for the related consensus problem is also given.  相似文献   
75.
The authors have been investigating the adsorption and desorption dynamics of nonionic water soluble polymers on inorganic particles. The influence of the nature of polymers with and without associating hydrophobic end groups, the nature of adsorbents [TiO2, Al2O3 (neutral, acid and basic), and SiO2], polymer concentrations, linear velocity of fluids, and mutual diffusion of polymer molecules on the patterns of adsorption and desorption distribution of polymer concentrations are shown. The model polymer is a nonionic polyurethane polymer based on ethylene oxide. The polymer's structure is R-O-(DI-PEO)6-DI-O-R (R is C16H33, DI is isophorone diisocyanate, and PEO is CARBOWAXTM with a molecular weight of 8200). The phenomenological models of association and dissociation kinetics of associative polymers are suggested. The half-lives of clusters into adsorption and desorption layers are estimated. It is shown that heats of desorption of associative polymers are dependent essentially on heats of dissociation of clusters.  相似文献   
76.
Objects of geological investigations, with subsequent technologic impact (e.g., secondary and tertiary recovery) on them, are dynamic systems. They change either in geologic or “technologic” time scale. Thus, in order to develop adequate models of geologic and technologic processes, it is necessary to introduce time factor.The writers offer two methods in constructing such models: analytical and statistical. They allow construction of a series of models for geologic and geotechnologic processes, such as (1) compaction of sediments, (2) development of geofluidal pressures (pore fluid pressures), (3) accumulation of hydrocarbons at depth and in local traps, (4) changes in water saturation of reservoir during its development, and (5) changes in physical and reservoir properties of rocks with time. The writers propose algorithms for computer analysis of data. All models found application in solving practical and theoretical exploration and development problems of oil and gas deposits.  相似文献   
77.
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79.
The heterobimetallic lantern complex Pd(μ-OOCMe)4Zn(OH2) was found to be readily reduced with H2 under fairly mild conditions (150–250 °C, 5–10% H2/He) both in the carbon-supported and crystalline states to afford a Pd–Zn nanoalloy as evidenced by the ICP elemental analysis, EXAFS, XANES and XRD data.   相似文献   
80.
Objectives: To assess potential infant exposure to bupropion and its active metabolites in breast milk such as would occur during treatment to prevent post-partum relapse to tobacco use, and to compare the concentrations of bupropion in urine and saliva with plasma and breast milk.

Design and setting: Cohort study, outpatient clinical research centre.

Subjects: Ten healthy post-partum volunteers who agreed to take bupropion for seven days, pump and discard their breast milk, and have samples of breast milk, plasma, saliva, and urine analysed.

Intervention: Bupropion 150 mg a day for three days and then 300 mg a day for four days.

Main outcome measures: Concentrations of bupropion and its active metabolites (hydroxybupropion, erythrohydrobupropion, threohydrobupropion) in breast milk, plasma, saliva, and urine. Determination of average infant exposure.

Results: The calculated average dosage of bupropion in breast milk was 6.75 µg/kg/day. Therefore, the average infant exposure is 0.14 % of the standard adult dose of bupropion, corrected for the difference in body weight. Considering the sum of bupropion and its active metabolites, the average infant exposure is expected to be 2% of the standard maternal dose on a molar basis. The concentration of bupropion and its active metabolites in breast milk was not associated with age, body mass index, use of oral contraceptive pills, age of infant, or the frequency of breast feeding at the time the study was initiated. The coefficient of determination (r2) between the concentration of bupropion in breast milk and in urine was 0.77 (p < 0.01).

Conclusions: Bupropion and its active metabolites are present in the breast milk of lactating women. The concentrations of bupropion in breast milk and urine were highly correlated. These results indicate that the daily dose of bupropion and metabolites that would be delivered to an infant of a woman taking a therapeutic dose of bupropion is small. These results suggest that the effectiveness of bupropion to prevent post-partum relapse to tobacco use should be evaluated without excluding women who plan to breast feed.

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