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91.
Rob N.J. Comans 《Water research》1987,21(12):1573-1576
Adsorption, desorption and isotopic exchange of Cd on illite clay have been studied at low Cd concentrations and low ionic strength. The results indicate that under the conditions of the experiments Cd sorption on illite is completely reversible. Long equilibration times (7–8 weeks) were shown to be essential because of slow desorption kinetics.  相似文献   
92.
Salmonellosis is the 2nd most common cause of human bacterial food poisoning and can be acquired from meat or eggs, either via direct consumption or cross‐contamination in the kitchen. The European Commission has set the criteria to control Salmonella infections within the poultry sector and it is proposed that the swine sector should follow. Pork is considered, after eggs, the major source of infection in humans in the EU, with Salmonella typhimurium, including monophasic strains, being frequently implicated. Good control measures at the farm level are likely to correspond with lower prevalence of Salmonella infection and, subsequently, a reduction of cross‐contamination of carcasses processed at the slaughterhouse and a reduction in human salmonellosis. This review focuses on biosecurity measures in pig farms that can help to control important pig diseases at the same time as reducing the within‐herd prevalence of Salmonella. This information is likely to provide an economic incentive for farmers to apply improved general standards of farm biosecurity and hygiene management that would have a positive impact in food safety.  相似文献   
93.
Detector physics and simulation of resistive plate chambers   总被引:1,自引:0,他引:1  
We present a simulation model suited to study efficiency, timing and pulse-height spectra of Resistive Plate Chambers. After discussing the details of primary ionisation, avalanche multiplication, signal induction and frontend electronics, we apply the model to timing RPCs with time resolution down to 50 ps and trigger RPCs with time resolution of about 1 ns.  相似文献   
94.
We present congruence formats for η- and rooted η-bisimulation equivalence. These formats are derived using a method for decomposing modal formulas in process algebra. To decide whether a process algebra term satisfies a modal formula, one can check whether its subterms satisfy formulas that are obtained by decomposing the original formula. The decomposition uses the structural operational semantics that underlies the process algebra.  相似文献   
95.
Multimedia Tools and Applications - Personalization is an upcoming trend in gamification research, with several researchers proposing that gamified systems should take personal characteristics into...  相似文献   
96.
In this paper we analyze the problem of a penny-shaped hydraulic fracture propagating parallel to the free-surface of an elastic half-space. The fracture is driven by an incompressible Newtonian fluid injected at a constant rate at the center of the fracture. The flow of viscous fluid in the fracture is governed by the lubrication equation, while the crack opening and the fluid pressure are related by singular integral equations. We construct two asymptotic solutions based on the assumption that either the solid has no toughness or that the fluid has no viscosity. These asymptotic solutions must be understood as corresponding to limiting cases when the energy expended in the creation of new fracture surfaces is either small or large compared to the energy dissipated in viscous flow. It is shown that the asymptotic solutions, when properly scaled, depend only on the dimensionless parameter cal R cal, the ratio of the fracture radius over the distance from the fracture to the free-surface. The scaled solutions can thus be tabulated once and for all and the dependence of the solution on time can be retrieved for specific parameters, through simple scaling and by solving an implicit equation.  相似文献   
97.
98.
The shift of electronics industry towards the use of lead-free solders in components manufacturing brought also the challenge of addressing the problem of tin whiskers. Manufacturers of high reliability and safety critical equipment in sectors such as defence and aerospace rely increasingly on the use of commercial-of-the-shelf (COTS) electronic components for their products and systems. The use of COTS components with lead-free solder plated terminations comes with the risks for their long term reliability associated with tin whisker growth related failures. In the case of leaded type electronic components such as Quad Flat Package (QFP) and Small Outline Package (SOP), one of the promising solutions to this problem is to “re-finish” the package terminations by replacing the lead-free solder coatings on the leads with conventional tin–lead solder. This involves subjecting the electronic components to a post-manufacturing process known as Hot Solder Dip (HSD). One of the main concerns for adopting HSD (refinishing) as a strategy to the tin whisker problem is the potential risk for thermally induced damage in the components when subjected to this process.  相似文献   
99.
The related goals of the research were to delineate the domain of discontinuity, 1st by demonstrating its occurrence in a nonmatrix situation and, 2nd, by establishing the antecedent outcome conditions necessary for producing a discontinuity effect. The 1st goal was met by designing a mixed motive situation involving the production of origami products. Under these conditions, the magnitude of the discontinuity effect did not significantly differ from that in a matrix-only condition. The 2nd goal was met by a separate experiment that used H. H. Kelley and J. W. Thibaut's (1978) analysis of degree of noncorrespondence of outcomes. This experiment demonstrated that as noncorrespondence increased, so did the rate of competitive responding by groups but not by individuals. This pattern was qualified by an interaction with gender such that competitiveness was more markedly affected by noncorrespondence for groups of women than for groups of men. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
100.
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