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71.
The Victoria Planning Provisions (VPPs) include siting and design regulations incorporated into local government planning schemes to mitigate risk in areas prone to bushfires. Introduced in 1997, these provisions were previously called the Wildfire Management Overlay (WMO). Now updated and renamed the Bushfire Management Overlay (BMO), the provision's ongoing development has been informed by fire behaviour and how houses ignite. The aim of the research reported here, conducted following the catastrophic February 2009 Victorian fires, was to review dwelling losses in terms of the WMO's effectiveness. Empirical evidence compares house losses of dwellings referred to the Country Fire Authority (CFA) via the WMO, with overall house losses. The results suggest that proportionately fewer houses referred to the CFA were lost, compared with those not assessed under the WMO. It should be noted that other factors influenced the results, such as the houses assessed under the WMO being generally newer. 相似文献
72.
Entwicklung eines optisch zugänglichen Reaktors zur Thermographiemessung in einer Katalysatorschüttung
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To measure the microkinetics in heterogeneously catalyzed strongly exothermic gas phase reaction heat and mass transfer limitations should be excluded. Also an unequal distribution of temperature in the catalyst fixed bed, like a hot spot, distorts the results of microkinetic investigations. A promising approach to measure the temperature contactless is thermography. For this work, an optically accessible reactor is developed to measure the temperature in a catalytically powder fixed bed. In the scope of this work, this technique is used to investigate the temperature development and distribution during the exothermal CO2 methanation depending on the bed and gas dilution and the reactor performance. 相似文献
73.
James A. Birrell Kathrin Wrede Krzysztof Pawlak Patricia Rodriguez-Maciá Olaf Rüdiger Edward J. Reijerse Wolfgang Lubitz 《Israel journal of chemistry》2016,56(9-10):852-863
Hydrogenases catalyze the reduction of protons and oxidation of molecular hydrogen with high turnover frequencies and low overpotentials under ambient conditions. The heterodimeric [FeFe] hydrogenase from Desulfovibrio desulfuricans has an exceptionally high activity, and can be purified aerobically in an oxygen-stable inactive state. Recently, it was demonstrated that monomeric [FeFe] hydrogenases produced recombinantly in Escherichia coli can be artificially maturated by simply incubating the inactive “apo” enzymes with the synthetic [2Fe] cofactor mimic [Fe2(adt)(CO)4(CN)2]2−. Here, we use the same technique to produce the heterodimeric “apo” hydrogenase from D. desulfuricans in E. coli with a high yield and purity, and maturate the “apo” enzyme with [Fe2(adt)(CO)4(CN)2]2− to generate fully active “holo” enzyme. Interestingly, the rate of the artificial maturation process with D. desulfuricans is significantly slower than that for all other hydrogenases tested so far. The artificially maturated enzyme is spectroscopically and electrochemically identical to the native enzyme and shows high rates of hydrogen production (3700 s−1) and hydrogen oxidation (63,000 s−1). We expect that our highly efficient production method will facilitate future studies of this enzyme and other related [FeFe] hydrogenases from Desulfovibrio species. 相似文献
74.
75.
New concepts for the utilisation of residual products from food industry - Prospects for the potato starch industry. In disposed waste are quite a lot of reusable substances of high value. These residual products can be transferred into commercial products in dependency to the adequate technology either as raw material for secondary processes, as operating supplies or as ingredients of novel products. Numerous valuable substances in food production are suitable for separation and recycling at the end of their life cycle even though present separation and recycling processes are not absolutely cost saving. Based on a concept of food production in its entirely the actual state is exemplary demonstrated at the potato starch industry in its occurrence, quantity and utilisation of the residual products. The target state of a clean production process will be realised by the development of multifunctional food ingredients. The outlined concept can be naturally transferred to several areas of industrial food production. The intentions of this research area are located at the development of techniques, which fulfil the conditions of environmental protection with costs to a minimum. 相似文献
76.
Eckhart Nietzschmann Olaf Bge Alfred Tzschach 《Advanced Synthesis \u0026amp; Catalysis》1991,333(2):281-284
Ultrasound-induced Synthesis of Trimethylsilylacetic Acid Trimethylsilylester . The reaction of bromoacetic acid trimethylsilylester with zinc in presence of chlorotrimethylsilane is promoted by sono-waves. The trimethylsilylacetic acid trimethylsilylester could be obtained in high yield. Different products are observed in presence of dichloro dimethylsilane. Mechanical aspects are discussed. 相似文献
77.
Schecter A Harris TR Shah N Musumba A Päpke O 《Molecular nutrition & food research》2008,52(2):266-272
We and others recently began studying brominated flame retardant levels in various matrices in the US including human milk and other food. This paper reviews the food studies. In our studies, ten to thirteen polybrominated diphenyl ether (PBDE) congeners were measured, usually including BDE 209. All US women's milk samples were contaminated with PBDEs from 6 to 419 ng/g, lipid, orders of magnitude higher than levels reported in European studies, and are the highest reported worldwide. We compared our market basket studies of meat, fish and dairy products with other US food studies of meat and fish. US studies showed somewhat higher levels of PBDEs than reported elsewhere. Fish were most highly contaminated (median 616 pg/g), then meat (median190 pg/g) and dairy products (median 32.2 pg/g). However, unlike some European countries where fish predominates, dietary intake of PBDEs in the US is mostly from meat, then fish and then dairy products. Broiling can decrease the amount of PBDEs per serving. We also measured levels of hexabromocyclododecane (HBCD), another brominated flame retardant, in human milk. The levels are lower than PBDEs, 0.16-1.2 ng/g, similar to European levels, unlike PBDEs where US levels are much higher than European levels. 相似文献
78.
Ga2O3/GdGaO dielectric stacks have been grown on GaAs for MOSFETs. This paper highlights variations in the characteristics of GdGaO as the Gd flux, Ga2O flux and substrate temperature are changed. The growth rate, composition, crystallinity are discussed and the sheet resistance of final MOSFET structures are presented. The Gd compositional variation with depth is examined using Rutherford back scattering (RBS) and electron energy loss spectroscopy (EELS). 相似文献
79.
Abstract The relationship between microsystems and macrosystems is considered in the context of quantum field formulation of statistical mechanics: it is argued that problems on foundations of quantum mechanics can be solved relying on this relationship. This discussion requires some improvement of non-equilibrium statistical mechanics which is briefly presented. 相似文献
80.
Olaf Ostwald 《Cryptologia》2017,41(5):395-421
“Breaking German Army Ciphers” is the title of a Cryptologia article from 2005, describing the lucky survival of several hundred authentic Enigma messages of World War II, and an account of a ciphertext-only cryptanalysis of a large number of these messages, leaving only a few (mostly short messages) unbroken. After reviewing the work done, and investigating the reasons for both lucky breaks and close misses, the modern ciphertext-only attack on Enigma messages is improved, especially on genuine ones with short lengths and/or many garbles. The difficulties of a proper measure for the candidate’s closeness to a plaintext are clarified. The influence on the decryption process of an empty plugboard and one with only a few correct plugs is examined. The method is extended by a partial exhaustion of the plugboard combined with an optimized hillclimbing strategy. The newly designed software succeeds in breaking formerly unbroken messages. 相似文献