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71.
Needles and noodles: Studying amyloid toxicity is important for understanding protein misfolding diseases. Using a luminescent conjugated polythiophene, we found that cell binding of nontoxic filamentous amyloids of insulin and β2-microglobulin was less efficient than that of toxic fibrillar amyloids; this suggests a correlation between amyloid toxicity and cell binding.  相似文献   
72.
An increasing number of components in automotive structures are today made from advanced high strength steel (AHSS). Since AHSS demonstrates more severe springback behaviour than ordinary mild steels, it requires more efforts to meet the design specification of the stamped parts. Consequently, the physical fine tuning of the die design and the stamping process can be time consuming. The trial-and-error development process may be shortened by replacing most of the physical try-outs with finite element (FE) simulations of the forming process, including the springback behaviour. Still it can be hard to identify when a stamped part will lead to an acceptable assembly with respect to the geometry and the residual stress state. In part since the assembling process itself will distort the components. To resolve this matter it is here proposed to extend the FE-simulation of the stamping process, to also include the first level sub-assembly stage. In this study a methodology of sequentially simulating each step in the manufacturing process of an assembly is proposed. Each step of the proposed methodology is described, and a validation of the prediction capabilities is performed by comparing with a physically manufactured assembly. The assembly is composed of three sheet metal components made from DP600 steel which are joined by spot welding. The components are designed to exhibit severe springback behaviour in order to put both the forming and subsequent assembling simulations to the test. The work presented here demonstrates that by using virtual prototyping it is possible to predict the final shape of an assembled structure.  相似文献   
73.
Lipozyme IM‐catalyzed interesterification of the oil blend between palm stearin and coconut oil (75/25 w/w) was studied for the production of margarine fats in a 1 kg scale batch stirred tank reactor. Parameters such as lipase load, water content, temperature, and reaction time were investigated. The reusability of Lipozyme IM was also studied under optimized conditions. The interesterification products were monitored by analysis of triacylglycerol profiles, the contents of diacylglycerols, free fatty acids (FFA), and solid fat contents. The contents of some triacylglycerol species, which were categorized by equivalent carbon number (ECN), namely ECN34, 36, 48, and 50, decreased by 6.0, 5.9, 5.8, and 13.7%, respectively, after enzymatic interesterification, similar to the reduction of those species after chemical interesterification, 6.6, 6.0, 7.1, and 12.9%, respectively. On the other hand, those of ECN38, 40, 42, 44, and 46 increased by 1.1, 1.6, 6.8, 16.7, and 6.5%, respectively, in comparison with the increase of those species after chemical interesterification, 0.2, 1.5, 6.5, 17.0, and 9.2%, respectively. Lipase load and reaction time had great influence on the degree of interesterification. A Lipozyme IM load of 6% was required for a reaction of 6 h and at 60 °C, to reach a stable degree of interesterification. Temperature variation in the range of 50—75 °C did not affect the reaction degree as well as the contents of diacylglycerols, but the content of FFA slightly increased with higher temperature. Addition of water to the enzyme increased the contents of diacylglycerols and FFA in the products linearly. However, it had no effect on the degree of interesterification for the first batch when the enzyme was reused. Lipozyme IM was stable in the 10‐batch test after adjusting the water content in the system. The relationship between the content of water in the system and that of FFAs in the products was evaluated and discussed.  相似文献   
74.
Light up galectin: Photoprobes based on thiodigalactoside were prepared for galectin‐3, a lectin linked to cancer. The probes contained either benzophenone or acetophenone moieties as the photolabel for covalent attachment to the protein. One particular probe labeled galectin‐3 selectively, even in the presence of cell lysate.

  相似文献   

75.
Incremental pressure programming was demonstrated to be an effective technique for increasing the yield of 90% pure allcis-5,8,11,14,17-ethyl eicosapentaenoate (EPA) in the fractionation of urea-crystallized fish oil ethyl esters using supercritical fluid CO2. The fractionations, which also produced high purity allcis-4,7,10,13,16,19-ethyl docosahexaenoate (DHA), were performed using a column temperature gradient. In initial experiments, the maximum temperature of the superimposed gradient was 80°C, and processing pressures ranged from 1900–2200 psi. By reduction of processing pressures, comparable yields of EPA were obtained from fractionations in which the maximum temperatures in the gradient were 70°C and 60°C.  相似文献   
76.
A strategy that combines virtual screening and structure‐guided selection of fragments was used to identify three unexplored classes of human DHODH inhibitor compounds: 4‐hydroxycoumarins, fenamic acids, and N‐(alkylcarbonyl)anthranilic acids. Structure‐guided selection of fragments targeting the inner subsite of the DHODH ubiquinone binding site made these findings possible with screening of fewer than 300 fragments in a DHODH assay. Fragments from the three inhibitor classes identified were subsequently chemically expanded to target an additional subsite of hydrophobic character. All three classes were found to exhibit distinct structure–activity relationships upon expansion. The novel N‐(alkylcarbonyl)anthranilic acid class shows the most promising potency against human DHODH, with IC50 values in the low nanomolar range. The structure of human DHODH in complex with an inhibitor of this class is presented.  相似文献   
77.
Experiments were carried out in a laboratory fluidized bed (FB) to characterize the devolatilization behavior of wood and various wastes at temperatures applicable to FB gasification and combustion, i.e. 750-900 °C. The fuels tested were pellets made of wood, meat and bone meal, and compost (from municipal solid wastes), as well as dried granulates of sewage sludge (DSS). Determination of yields of char, condensate and light gas, as well as the composition of the gas and the time of devolatilization during the pyrolysis of single fuel batches was made. A simple model was developed to analyze the mode of conversion of a single wood pellet and DSS granulate, giving insight on the controlling mechanisms during devolatilization. The devolatilization kinetics of DSS was determined by tests using fine granulates. The model was successfully applied to simulate the conversion of large DSS granulates and wood pellets under the whole range of temperatures analyzed.  相似文献   
78.
79.
A dynamic mathematical model for simulating the coupled heat and moisture migration through multi-layer porous building materials was proposed. Vapor content and temperature were chosen as the principal driving potentials. The discretization of the governing equations was done by the finite difference approach. A new experimental set-up was also developed in this study. The evolution of transient temperature and moisture distributions inside specimens were measured. The method for determining the temperature gradient coefficient was also presented. The moisture diffusion coefficient, temperature gradient coefficient, sorption–desorption isotherms were experimentally evaluated for some building materials (sandstone and lime-cement mortar). The model was validated by comparing with the experimental data with good agreement. Another advantage of the method lies in the fact that the required transport properties for predicting the non-isothermal moisture flow only contain the vapor diffusion coefficient and temperature gradient coefficient. They are relatively simple, and can be easily determined.  相似文献   
80.
Unannounced evacuation experiments in a cinema theatre were analysed. The analysis focused on investigating if people are influenced by others during the initial phase of a fire evacuation. This type of influence is called social influence. Three separate behaviour types were identified and studied and the recognition and pre-movement time was measured. The results suggest that social influence is an important factor and that it becomes more important when the fire cue, e.g., the alarm, is unclear or uninformative. Results also indicate that social influence increases with decreasing distance between visitors. This result implies that individuals are influenced more by people who are close than by people who are further away.  相似文献   
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