The Conversion of a Boron-Containing Pyrotechnic Mix to a “Ceramic-Like” Material by Electron Beam Interaction

The transformation of a boron-containing pyrotechnic mix to a “ceramic” vitreous-like material by the impingement of an electron beam on a boron-barium chromate pyrotechnic, in a scanning electron microscope, is reported. The thickness of the “ceramic”-like material is ×250 the penetration depth for the electron beam and indicates that a self-sustaining chemical reaction was induced by interaction of the energetic material with the electron beam at temperatures well below the mix's ignition temperature of over 1000?°C. This links with earlier observations on the low-temperature liquefaction of boron to boron suboxides in an electron microscope.     

GROWTH DYNAMICS OF INDIGENOUS MICROBIAL POPULATIONS ON VEGETABLES AFTER DECONTAMINATION AND DURING REFRIGERATED STORAGE

To ensure microbiological stability and safety in minimally processed (MP) salad vegetables, it is essential to consider the microbiology of this produce during cultivation and harvesting, and the potential changes to this microbiology through preparation, distribution and storage. This study takes two salad vegetables (lettuce and white cabbage) and, having enumerated a range of different physiological groups of microorganisms present on unwashed produce, determines the impact on each microbial group of applying a decontamination step in the preparation protocol. The disinfectant used was sodium dichloroisocyanurate. Decontamination reduced the total microbial load significantly on both vegetables. The levels of different microbial groups enumerated differed significantly between vegetables. All the microbial populations were reduced, but the biocidal effect of chlorine treatment varied with vegetable type. Reduction of the levels of lactic acid bacteria and aerobic psychrotrophs on cabbage was only achieved with inclusion of the decontamination step, and this effect, in general, did not last more than 3 days. Decontamination significantly reduced the levels of coliforms, and although the levels increased during refrigerated storage, they did not exceed initial levels found on unwashed produce. In addition, the levels found on treated cabbage remained lower than produce washed with water only.     

EVALUATION OF SWEET POTATO CULTIVARS AND HEATING METHODS FOR CONTROL OF MALTOSE PRODUCTION, VISCOSITY AND SENSORY QUALITY

Two varieties of sweet potato were subjected to four cooking temperature‐time combinations. A fifth treatment involved adding maltose syrup. Raw comminuted sweet potato mash and cooked sweet potato puree were evaluated for total solids, alcohol insoluble solids, commonly occurring sugars, viscosity (puree only) and for starch gelatinization temperatures. The uncooked Owairaka Red variety was higher in total solids and in alcohol insoluble solids than the Toka Toka Gold. With the exception of the cooked puree with added maltose, baking at 200C resulted in puree with the highest maltose levels. A very fast cooking procedure tended to result in puree with lower levels of maltose and high viscosity. Sensory studies revealed that the Owairaka Red variety produced puree with more viscous and adhesive mouth feel. It was concluded that cooking alone could not be used to optimize both maltose production and viscosity.     

DISINFECTION OF SHREDDED SALAD INGREDIENTS WITH SODIUM DICHLOROISOCYANURATE

Raw salads are frequently subjected to hypochlorite wash to reduce microbial numbers, retard enzymatic activity and improve shelf-life of sensory quality. Hypochlorite dips significantly reduce the initial population of natural contaminants on lettuce. However, populations on treated and untreated samples are not significantly different after four days storage at refrigeration temperature. Increasing the level of free available chlorine does not improve the microbicidal effect.
In this study sodium dichloroisocyanurate (NaDCC) was used to disinfect salad vegetables. Though the principal salad vegetable used was butterhead lettuce, results show that the efficacy of NaDCC in reducing total aerobic mesophile levels varies with vegetable type. NaDCC gives an acid pH in solution and has significantly higher activity than sodium hypochlorite.
For longer term storage, preparation of lettuce which included a 30 min soak in NaDCC improved the microbiological quality of the produce at the end of the storage period. The microbial load on disinfected produce was between 0.62 and 0.98 log cycles lower than on lettuce prepared without a disinfection step for up     

EFFECT OF A VERTICAL FRACTURE ON HORIZONTAL UNSATURATED SEEPAGE FLOW

The movement of water flow in unsaturated fractured rock was investigated with the sandstone sample through experimental research and numerical simulation.The experimental results show that the arriving time of wetting front is delayed by the fracture,resulting in the increase of water saturation in the domain on the upstream side of the fracture,which will locally enhance water flow through the matrix.The numerical simulation with the finite volume method captures effectively these characteristics.The comparison between simulated and observed travel time and arriving time of wetting front shows that their difference are very small and the simulated results are in agreement with the observed results,which implies calibrated parameters are reliable and effective.Then according to the calibrated parameters,fractured models were established to examine how the change of large fractured aperture would affect the arriving time of wetting fronts,pressure heads and water saturation on the upstream and downstream sides of fracture.     

Historical continuity and post‐1945 urban redevelopment: the example of Lee Bank,Birmingham, UK

The reconstruction of British cities following World War II is characterized by a marked gap between the rhetoric and the reality. Visions for ideal cities, in particular those growing out of the modern movement in architecture, were diluted and warped by the ‘messy’ business of reconstructing actual cities, filled with real people whilst operating within democratic structures. This paper examines elements of this confrontation of the ideal and the real, by looking at the context for changes to the urban fabric within a single housing estate in Birmingham, self‐nominated ‘second city’ of Britain. The overarching theme is of historical continuity and change – the extent to which the urban fabric has been destroyed and remade. As such, the paper examines not only the nominally ‘modern’ post‐war reconstruction, but also how a contemporary, ‘post‐modern’ phase of redevelopment is dealing with the city form created in the 1950s and 1960s.     

把云内容引入汽车连接服务与应用的路线图指明方向

由于智能手机,最近汽车信息娱乐更加受到欢迎,正在改变客户对于信息娱乐解决方案功能与用途的期望.     

CONSUMER RESPONSE TO INFORMATION ON INTEGRATED PEST MANAGEMENT

Risk communication theory is used to address consumer concerns about food safety and pesticide residues. Risk perception is a function of actual hazard and "outrage"factors. If concerns are acknowledged and information is provided on how risks are being addressed, the outrage component of perception is reduced. Two 2-min videos were prepared to present information on the environmentally responsive integrated pest management (IPM) approach to farming. The video was shown to a total of 197 consumers in controlled group settings. Although about 90% of participants expressed confidence in the safety of produce grown in California and the United States, 40% said they avoided some produce items due to safety concerns. Pre-and post-attitude assessments and group discussions documented a significant change in attitudes toward food safety, farming practices, and university efforts to help farmers. This project indicates that consumer concerns are significantly reduced when their knowledge of IPM practices is increased.