Influence of Ignition Sources on Heat Release Rate in the Furniture Calorimeter

When measuring the production rates of heat and smoke of upholstered furniture the ignition source must not influence the test results. In this paper variations in the strength, application time and geometry of the ignition burner used in the furniture calorimeter are studied. Results from replicate furniture calorimeter chair test show that the burning behaviour is almost independent of the burner intensity in the applied regime. Tests on six different furniture items were performed in the furniture calorimeter. The test objects were exposed to three intensity levels of ignition source. The sources were: a large propane burner giving 30 kW during 120 s and a smaller propane burner used at two levels of heat output, 1.7 and 5.8 kW during 90 s. The results showed that the burning behaviour of the furniture was very similar regardless of which burner was used. This was especially evident when the time regime between 50 and 400 kW was studied. The length of this period is a measurement on how quick untenable conditions are developing in a single, well-ventilated compartment.     

PM Aluminum Camshaft Belt Pulleys for Automotive Engines

Light and wear resistant Al camshaft belt pulleys for engines were produced from standard Al powder mixtures with addition of hard particles. Pre-screening tests of numerous inclusions showed 10 mass% ZrSiO₄ to be the best choice. Full size belt pulleys were produced by pressing, sintering at optimized parameters, and sizing. Wear testing was carried out on pin-disc testers and special belt pulley testbeds. Both dimensional and wear properties were found to be well comparable to those of conventional iron pulleys, with the exception of some attack on the belt by protruding particles after prolonged testing.     

用于后端工艺中铜/低k材料金属去除的实验数值研究

1 Introduction The consumer electronics market demands high-er speeds and more functionality of ICs. Speed and functionality of an IC are related to the amount of cir- cuitry (such as transistors), which is packed on eachchip. Therefore, the dimensions of the transistors need to be reduced. The interconnect structure, which con- nects the transistors, must become smaller too to com- ply with the small dimensions of the transistors. In or- der to reduce undesirable effects[1], which follow fr…     

Hanging cloths and dangling rods: A unified approach to constraints in computer animation

A simple unified approach for dealing with constraints on real-valued parameters in computer simulations and computer animation is described. The main characteristics of the approach are its flexibility (it works for a variety of constraint-types and it can be implemented to handle both under- and over-constrained systems in a stable way) and its ease for distributed computation. The method is based on the idea of genetic algorithms. The mathematical merits of the method for one constraint-type are discussed in some detail and some examples of applications are given.     

The Dehydration of Fructose Towards 5-Hydroxymethylfurfural Using Activated Carbon as Adsorbent

5-Hydroxymethylfurfural (HMF) can be selectively adsorbed onto activated carbon with loadings up to 30% (w/w), depending on the type of carbon used. Adsorption isotherms of HMF on several types of carbon and in different solvents are presented. Activated carbon is used in in the dehydration of fructose towards HMF in order to suppress the formation of side-products (e. g. levulinic acid). A dehydration set-up in which the formation and adsorption of HMF take place at different temperatures is presented. The HMF is recovered by extraction of the loaded activated carbon with organic solvent.     

Preparation and Calcium Complexation of Oxidized Polysaccharides. Part I: Oxidation of Maltodextrins and Starch with Alkaline Sodium Hypochlorite

The oxidation of maltodextrins and starch with aqueous alkaline sodium hypochloride has been studied. At an oxidant level of 3 moles hypochlorite per anhydroglucose unit at pH 8–9, a C2, C3-glycol-cleaved dicarboxy polysaccharide was obtained containing up to 45% ring-opened glucose units. Hydrolysis of the oxidation products yielded (apart from glucose) erythronic and glyoxylic acids, but no glucuronic acid evidencing the absence of C6-oxidation. The average degree of polymerization of the products ranged from 14 to 87 and indicated severe chain degradation during the oxidation. The products were shown to be effective calcium complexing agents and behaved as regular polyelectrolytes with identical complexing sites.     

On the Origin of a Low Angle Spacing in Starch

The structure of starch granules from different botanical sources was studied by transmission electron microscopy and small-angle X-ray diffraction. Electron micrographs of negatively stained starch granule fragments show a rippled fibrous structure. The ripples are interpreted as being stacks of thin crystalline lamellae comprising the linear α-(1→4) chains of the amylopectin. Optical diffraction analysis of the electron micrographs showed that the spacing of the ripples varies from 9.2 nm in potato starch to 10.4 nm in barley starch. This correlates well with the position of a Bragg peak at appr. 10 nm measured by small-angle X-ray diffraction. These observations indicate that the Bragg peak arises from the alternating amorphous and crystalline regions seen as ripples in the electron micrographs.     

Vapor- and liquid-phase adsorption of alcohol and water in silicalite-1 synthesized in fluoride media

In this work, batch-adsorption experiments and molecular simulations are employed to probe the adsorption of binary mixtures containing ethanol or a linear alkane-1,n-diol solvated in water or ethanol onto silicalite-1. Since the batch-adsorption experiments require an additional relationship to determine the amount of solute (and solvent) adsorbed, as only the bulk liquid reservoir can be probed directly, molecular simulations are used to provide a relationship between solute and solvent adsorption for input to the experimental bulk measurements. The combination of bulk experimental measurements and simulated solute–solvent relationship yields solvent and solute loadings that are self-consistent with simulation alone, and allow for an assessment of the various assumptions made in the literature. At low solution concentrations, the solute loading calculated is independent of the assumption made. At high concentrations, a negligent choice of assumption can lead to systematic overestimation or underestimation of calculated solute loading.