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81.
Summary Methacrylate-type poly(vinylidene fluoride) macromonomer was synthesized from vinylidene fluoride via hydroxy-ended poly(vinylidene fluoride). The macromonomer copolymerized easily with methyl methacrylate, but homopolymerization did not proceed completely.  相似文献   
82.
83.
MRI study of bread baking: experimental device and MRI signal analysis   总被引:1,自引:0,他引:1  
An oven dedicated to a magnetic resonance imager (MRI) was designed and constructed for continuous monitoring of the entire baking process. The general aim was to test whether response variables conventionally measured on bread loaves, such as temperature, density, and water loss, were consistent with those reported for similar products baked in classical convection ovens. MRI images acquired during baking are presented and discussed, emphasising the need to develop quantitative MRI methods allowing conversion of the MRI signal into one variable of interest, such as local density or local water content.  相似文献   
84.
Careful structural investigations have been carried out on the Bi1.5ZnNb1.5O7 based dielectric system (of A 2 B 2O7 pyrochlore structure type) in an attempt to understand the origin and tolerance of relaxor behavior in such materials. A highly structured, characteristic diffuse intensity distribution was observed in electron diffraction patterns, which arises from static disordering caused by local short range ordering of Bi and Zn ions on the pyrochlore A sites and associated structural relaxation of the O’A 2 sub-structure. This structural disordering is not affected by B site substitution of the Nb5+ ions by Sn4+ or Ti4+ ions. The result is of significance for optimizing the dielectric properties of bismuth-based advanced ceramics.  相似文献   
85.
Due to the language barrier, non-English users are unable to retrieve the most updated medical information from the U.S. authoritative medical websites, such as PubMed and MedlinePlus. However, currently, there is no any cross-language medical information retrieval (CLMIR) system that can help Chinese-speaking consumers cross the language barrier in finding useful English medical information. A few CLMIR systems utilize MeSH (Medical Subject Headings) to help overcome the language barrier. Unfortunately, the traditional Chinese version of MeSH is currently unavailable.In this paper, we employ a semi-automatic term translation method to construct a Chinese–English MeSH by exploiting abundant multilingual Web resources, including Web anchor texts and search–result pages. Through this method, we have developed a Chinese–English Mesh Compilation System to assist knowledge engineers in compiling a Chinese–English medical thesaurus with more than 19,000 entries. Furthermore, this thesaurus has been used to develop a prototypical system for cross-language medical information retrieval, MMODE, which can help consumers retrieve top-quality English medical information using Chinese terms.  相似文献   
86.
Fair-exchange is an important property that must be ensured in all electronic commerce environments where the merchants and the customers are reluctant to trust each other. This property guarantees that none of the transacting parties suffer because of the fraudulent behavior of the other party in the transaction. In this paper, we describe our experiences in developing a new e-commerce protocol to address the problem of fair-exchange for digital products. The protocol is based on a novel cryptographic technique that we had proposed earlier. We show how to use common off-the-shelf software components to develop such a protocol.  相似文献   
87.
The process of making decisions about the conception, design, development, deployment and regulation of complex information and communications technologies (ICT) systems with the potential to effect significant changes in society could be labelled ‘digital decision making’ (or DDM, for short). DDM is not the rational process that we might assume or wish it to be. It can even be difficult to define the boundaries of the social, political or technical environments to which the process applies. It depends on craft knowledge, power and agenda, politics and situational messiness, personal values, law and environment, and a host of other factors starkly illustrated by cases ranging from the Three Mile Island to the space shuttle Challenger disasters. Too often DDM leads to information systems failures, and it is time we started to learn from those past failures.  相似文献   
88.
89.
Recent efforts to influence the efficiency and timing of urban indoor water use through education, technology, conservation, reuse, economic incentives, and regulatory mechanisms have enabled many North American cities to accommodate population growth and buffer impacts of drought. It is unlikely that this approach will be equally successful into the future because the source of conservation will shift from indoor to outdoor use. Outdoor water is climate sensitive, difficult to measure, hard to predict, linked to other components of complex and dynamic urban resource systems, imbued with behavioral and cultural dimensions, and implicated in societal conflicts about climate risk, modern lifestyles, social justice, and future growth. Outdoor water conservation is not a traditional management problem focused on the water sector, assuming a stationary climate, and set aside from public debate. Instead, outdoor water is an adaptation problem, involving complex and uncertain system dynamics, the need for cross-sector coordination, strategies for dealing with climatic uncertainty, and mechanisms for engaging stakeholders with differing goals. This paper makes the case for treating outdoor water as an adaptation problem and offers a six-point strategy for how cities can better prepare their water systems for the uncertainties of climate and societal change.  相似文献   
90.
In this work, electrotreatment of nickel and boron containing plating rinse effluents was studied with mild steel and aluminum electrodes. Industrial effluent treatment directly by an electrochemical technique is capable of removing 80–85 % nickel. The residual nickel interfered with boron determination by curcumin method. The pH fall during electrotreatment in industrial effluent is due to electrodeposition of nickel at the cathode surface, evidenced by simulated effluent treatment. Nickel concentration can be reduced below the discharge limit from the industrial plating effluent by chemical precipitation and coagulation at pH above 8. Chemical precipitation showed maximum boron removal of about 50 %. Boron removal was 29.3–41.9 % and 20.6–33.1 % with ferric chloride and aluminum sulfate, respectively. A combination of chemical precipitation at pH 8.7 followed by electrotreatment reduces nickel to the discharge limit and also maximizes boron removal up to 59 %.  相似文献   
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