Synthesis and morphology of new functional polyimide/titania nano hybrid materials

The synthesis and full characterization of 3,5-diamino-N-(1-oxo-3-phenyl-1-(phenylamino)propan-2-yl)benzamide (5), as a new diamine monomer containing l-phenylalanine fractions in the structure of pendant group is presented. The stated diamine is employed as a key monomer for the in situ sol–gel fabrication of polyimide/titania nano hybrid thin films containing different titania contents. It is shown that titania particles are created in the size range of 20–80 nm, well-dispersed and enjoy the favorable spherical shapes supposing the constructive organic–inorganic interactions. The superior thermal stabilities of resulted nanocomposite films are confirmed using thermal analysis techniques. Moreover, the UV–Vis spectroscopy has shown the growing up in blocking efficiency along with the increase in titania contents. Predictably, the produced titania nanoparticles have amorphous structures.     

Effect of thermal treatments on functional properties of cress seed (Lepidium sativum) and xanthan gums: A comparative study

Foods are generally subjected to thermal treatments during processing operations, which affect on the functional properties of hydrocolloid solutions. In this paper, the effect of different thermal conditions (60 °C-30 min, 80 °C-23 min, 100 °C-18 min and 121 °C-15 min) on functional properties (rheological, emulsifying and foaming properties) of cress seed gum and xanthan gum were investigated. The results demonstrated that cress seed gum solutions had desirable rheological, emulsifying and foaming properties. When the hydrocolloid samples were heated, an irreversible increase in viscosity of cress seed gum solutions was observed and as a result, the emulsification and foaming properties improved. Whereas, xanthan gum would not have the ability to stand against heat treatment and its viscosity decreased. Nevertheless, the viscosity values of xanthan gum solutions were always higher than cress seed gum in all conditions.     

Pull-in behavior of functionally graded micro/nano-beams for MEMS and NEMS switches

Microsystem Technologies - In this paper, pull-in behavior of cantilever micro/nano-beams made of functionally graded materials (FGM) with small-scale effects under electrostatic force is...     

Temporal flux and spatial dynamics of nutrients, fecal indicators, and zoonotic pathogens in anaerobic swine manure lagoon water

Confined animal feeding operations (CAFOs) often use anaerobic lagoons for manure treatment. In the USA, swine CAFO lagoon water is used for crop irrigation that is regulated by farm-specific nutrient management plans (NMPs). Implementation of stricter US environmental regulations in 2013 will set soil P limits; impacting land applications of manure and requiring revision of NMPs. Precise knowledge of lagoon water quality is needed for formulating NMPs, for understanding losses of N and C in ammonia and greenhouse gas emissions, and for understanding risks of environmental contamination by fecal bacteria, including zoonotic pathogens. In this study we determined year-round levels of nutrients and bacteria from swine CAFO lagoon water. Statistical analysis of data for pH, electrical conductivity (EC), inorganic and organic C, total N, water-soluble and total minerals (Ca, Cu, Fe, K, Mg, Mn, P, and Zn) and bacteria (Escherichia coli, enterococci, Clostridium perfringens, Campylobacter spp., Listeria spp., Salmonella spp., and staphylococci) showed that all differed significantly by dates of collection. During the irrigation season, levels of total N decreased by half and the N:P ratio changed from 9.7 to 2.8. Some seasonal differences were correlated with temperature. Total N and inorganic C increased below 19 °C, and decreased above 19 °C, consistent with summer increases in ammonia and greenhouse gas emissions. Water-soluble Cu, Fe, and Zn increased with higher summer temperatures while enterococci and zoonotic pathogens (Campylobacter, Listeria, and Salmonella) decreased. Although their populations changed seasonally, the zoonotic pathogens were present year-round. Increasing levels of E. coli were statistically correlated with increasing pH. Differences between depths were also found. Organic C, total nutrients (C, Ca, Cu, Fe, Mg, Mn, N, P, and Zn) and C. perfringens were higher in deeper samples, indicating stratification of these parameters. No statistical interactions were found between collection dates and depths.     

Laminar heat transfer of non-Newtonian nanofluids in a circular tube

Forced convection heat transfer behavior of three different types of nanofluids flowing through a uniformly heated horizontal tube under laminar regime has been investigated experimentally. Nanofluids were made by dispersion of γ-Al₂O₃, CuO, and TiO₂ nanoparticles in an aqueous solution of carboxymethyl cellulose (CMC). All nanofluids as well as the base fluid exhibit shear-thinning behavior. Results of heat transfer experiments indicate that both average and the local heat transfer coefficients of nanofluids are larger than that of the base fluid. The enhancement of heat transfer coefficient increases by increasing nanoparticle loading. At a given Peclet number and nanoparticle concentration the local heat transfer coefficient decreases by axial distance from the test section inlet. It seems that the thermal entry length of nanofluids is greater than the base fluid and becomes longer as nanoparticle concentration increases.     

High-Performance Computing for Large-Scale Analysis, Optimization, and Control

Research papers published on parallel processing, supercomputing, and distributed computing since 1994 are reviewed in this article. The focus is on review of the archival journal articles published in three areas: analysis, optimization, and control. The review is divided into three main sections: (1) parallel processing on dedicated shared memory and distributed memory parallel machines; (2) distributed computing on a cluster of networked workstations; and (3) parallel computing and object-oriented programming. The great majority of the journal articles published since 1987 deal with fundamental issues and academic problems. The trend in the future, at least in part, should be more toward solution of large-scale and complicated real-life engineering problems, the kind of problems that cannot be solved readily by conventional uniprocessor computers.     

Apolipoprotein B is intracellularly associated with an ER-60 protease homologue in HepG2 cells

Two ALLN (N-acetyl-leucyl-leucyl-norleucinal)-sensitive endoplasmic reticulum (ER)-localized proteases (ER-60 and ER-72) were recently purified from rat liver. We used an antibody to rat ER-60 to investigate the possible role of this protease in apolipoprotein B (apoB) degradation. First, immunoprecipitation and immunoblotting experiments with the anti-rat ER-60 antibody suggested that HepG2 cells contain a homologue of ER-60 with an approximate molecular mass of 58-60 kDa. The ER-60 homologue was mostly associated with the luminal contents of HepG2 microsomes. Evidence from co-immunoprecipitation and cross-linking experiments appear to suggest that the ER-60 homologue in HepG2 cells is associated with apoB intracellularly. A small pool of apoB was recovered when HepG2 lysates were subjected to immunoprecipitation with anti-rat ER-60 antibody followed by a second immunoprecipitation with anti-apoB antibody. Furthermore, cross-linking of permeabilized cells with dithiobis(succinimidylpropionate) further demonstrated association of apoB with the ER-60 homologue in HepG2 cells. Three polypeptides with molecular masses of 78, 66, and 50 kDa were consistently found to be associated with apoB as well as the 58-kDa ER-60 homologue. The 78-kDa protein associated with both apoB and ER-60 appeared to represent immunoglobulin heavy chain-binding protein (BiP) based on immunoprecipitation with a monoclonal antibody. Cross-linking and immunoblotting experiments suggested the association of the 78-kDa BiP with both the 58-kDa ER-60 homologue as well as the 550-kDa apoB. In summary, the data suggests that HepG2 cells contain a 58-kDa protein which is homologous to the rat liver ER-60 in size, antigenecity, and intracellular localization. The ER-60 homologue in HepG2 cells appears to be closely associated with apoB, as well as other proteins possibly representing ER chaperones such as BiP. We hypothesize that the ER-60 homologue may be involved in the degradation of apoB in the ER lumen of HepG2 cells.     

Intracellular translocation and stability of apolipoprotein B are inversely proportional to the length of the nascent polypeptide

We have studied the relationship between the length of apolipoprotein B (apoB) and its intracellular translocation and stability using McArdle RH7777 (McA-RH7777) cells expressing recombinant human apoB variants, ranging in size from B15 to B100. The translocational status of apoB was assessed based on trypsin sensitivity of apoB using isolated microsomes as well as permeabilized cells. In isolated microsomes, shorter apoB variants (相似文献