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241.
Chemical recycling of waste poly(carbonate) (PC) to coproduce bisphenol A (BPA) and carbohydrate carbonates was studied by selecting glycerol (Gly) and glucose (Glu) as model carbohydrates (CHs). In advance of the reaction of PC with CHs, reactions with diphenyl carbonate were examined as a model PC. In dioxane at 100°C using NaOH as catalyst, Gly was converted to cyclic carbonate hydroxymethyldioxolane (HMDO) at 98% and Glu was converted to the dicarbonate (Glu-DC) at 46%, in pyridine, in addition to the production of phenol. Similar treatment of PC with Gly using KOH as a catalyst produced HMDO and BPA at very high yields and treatment with Glu produced Glu-DC and BPA in 38%–42% yields. Chemical Feedstock Recycling & Other Innovative Recycling Techniques 6  相似文献   
242.
Yang J  Kunito T  Anan Y  Tanabe S  Miyazaki N 《Chemosphere》2008,70(7):1203-1210
Total and subcellular renal Zn, Cu, Se, Mn, V, Hg, Cd and Ag were determined by a mother-fetus pair of Dall's porpoises (Phocoenoides dalli). All element concentrations in the maternal individual were higher than those in the fetal individual. Most of total renal elements studied were present in the cytosol of both animals. In maternal cytosol, Mn, Hg and Ag were present in high molecular weight substances (HMW); Se was in low molecular weight substances (LMW); Zn, Cu, and Cd were in metallothionein (MT), mostly; and the distribution of V in percentage among the three renal cytosolic fractions was similar. In fetal cytosol, Zn, Mn, Hg, V, Cd, and Ag were present in HMW, Cu was present in MT, mostly. In contrast, Se was observed mostly in both LMW and HMW. MT isoforms were characterized. Three obvious peaks in retention time were found in either the maternal or fetal MT. The highest elemental ion intensities were in the 7.8min peak for the mother, and in the 4.3min peak for the fetus, respectively, implying that different MT isoforms may be closely associated with elemental accumulation between maternal and fetal renal cytosols.  相似文献   
243.
Rice plays a major role in the global supply and demand for sustainable food production. The constraints of maintaining sustainable rice production are closely linked to the relationship between the distribution patterns of human activity on the planet and economic growth. Global patterns of rice production can be mapped by using various criteria linked to domestic income, population patterns, and associated satellite brightness data of rice-producing regions. Prosperous regions have more electric lighting, and there are documented correlations between gross domestic product (GDP) and nighttime light. We chose to examine global rice production patterns on a geographical basis. For the purposes of this study, each country is considered to be made up of regions, and rice production is discussed in terms of regional distribution. A region is delineated by its administrative boundaries; the number of regions where rice is produced is about 13,839. We used gridded spatial population distribution data overlain by nocturnal light imagery derived from satellite imagery. The resultant relationship revealed a correlation between regional income (nominal values of GDP were used) and rice production in the world. The following criteria were used to examine the supply and demand structure of rice. Global rice consumption = “caloric rice consumption per capita per day” multiplied by “regional population values”. Regional rice yields = “country-based production” divided by “harvested area” (multiple harvests are taken into account). Regional rice production = “regional harvested areas” multiplied by “rice yield values”. We compared regional rice consumption and production values according to these methods. Analysis of the data sets generated a map of rice supply and demand. Inter-regional shipping costs were not accounted for. This map can contribute to the understanding of food security issues in rice-producing regions and to estimating potential population values in such regions.  相似文献   
244.
The University of Tokyo started its Graduate Program in Sustainability Science (GPSS), offering a master of sustainability science degree, in 2007. The GPSS curriculum consists of: (1) knowledge and concept oriented courses, which cover sustainability-related subjects from a holistic viewpoint; (2) experiential learning and skills oriented practical courses, which offer practical exercises to acquire the skills and sensibility required of future leaders; and (3) the Master’s thesis, for which students are encouraged to address complex sustainability problems through a transdisciplinary approach. Sustainability science is not a discipline that can be defined simply by the subjects it deals with, but is an academic field characterized by core principles that include holistic thinking, transdisciplinarity, and respect for diversity. The GPSS has been designed so that students may gain the capacity to understand and practice these principles. The present paper describes how the GPSS has defined sustainability education and designed its curriculum accordingly.  相似文献   
245.
Local residents often oppose some types of facilities because of their negative side effects, even though they are claimed to be necessary for the public good. These facilities are known as locally unwanted-land-uses, and local opposition to them is often referred to as not-in-my-backyard, usually with a pejorative connotation. However, some studies have challenged this conventional view of local opposition. Given these conflicting views, the present article explores how local mobilisation should be evaluated, focusing particularly on distributive justice. First, the study illuminates how different interpretations of distributive justice lead to difference in views on local opposition. Then, by comparing three waste disposal facility cases in Japan, a distinction between cost sharing and cost overlapping cases is illuminated. The study further develops discussions by pointing out the limits of using this distinction to evaluate local opposition movements and provides insights that can contribute to a fuller understanding of siting conflicts.  相似文献   
246.
Objective: Hazard perception (HP) is the ability to identify a hazardous situation while driving. Though HP has been well studied among neurologically intact populations, little is known about the HP of neurologically impaired populations (in this study, stroke patients). The purpose of this study is, first, to investigate the HP of stroke patients and, second, to verify the effect of lesion side (right or left hemisphere) on HP, from the viewpoint of hazard types.

Methods: Sixty-seven neurologically intact age-matched older drivers and 63 stroke patients with valid driver’s licenses conducted a video-based Japanese HP task. Participants were asked to indicate the hazardous events in the driving scenario. These events were classified into 3 types: (1) behavioral prediction hazards (BP), which are those where the cause is visible before it becomes a hazard; (2) environmental prediction hazards (EP), which are those where the ultimate hazard may be hidden from view; and (3) dividing and focusing attention hazards (DF), which are those where there is more than one potential hazard to monitor on approach.Participants also took part in the Trail Making Test (TMT) to evaluate visual information processing speed.

Results: The results showed that the number of responses was significantly fewer for stroke patients than for age-matched drivers for all hazard types (P < .001), and this difference was not affected by lesion side (P > .05). It was also found that stroke patients showed a slower response time than age-matched drivers only for BP (P < .001). The lesion side did not affect response latency (P > .05). Results of the TMT revealed that age-matched drivers completed the task significantly faster than stroke patients (P < .001) and that neither TMT-A nor TMT-B differentiated between patients with left hemisphere damage and patients with right hemisphere damage (P > .05).

Conclusions: Firstly, HP in stroke patients is low compared to age-matched drivers. Secondly, even if stroke patients notice hazards, their response may be delayed in a BP situation, due to a slower visual information processing speed. Thirdly, the lesion side does not appear to affect HP.  相似文献   

247.
Appropriate treatment of asbestos-containing wastes is a significant problem. In Japan, the inertization of asbestos-containing wastes based on new treatment processes approved by the Minister of the Environment is promoted. A highly sensitive method for testing asbestos fibers in inertized materials is required so that these processes can be approved. We developed a method in which fibers from milled treated materials are extracted in water by shaking, and are counted and identified by transmission electron microscopy. Evaluation of this method by using asbestos standards and simulated slag samples confirmed that the quantitation limits are a few million fibers per gram and a few μg/g in a sample of 50 mg per filter. We used this method to assay asbestos fibers in slag samples produced by high-temperature melting of asbestos-containing wastes. Fiber concentrations were below the quantitation limit in all samples, and total fiber concentrations were determined as 47–170 × 10?6 f/g. Because the evaluation of treated materials by TEM is difficult owing to the limited amount of sample observable, this testing method should be used in conjunction with bulk analytical methods for sure evaluation of treated materials.  相似文献   
248.
Environmental Science and Pollution Research - Source-specific elucidation of domestic sewage pollution caused by various effluent sources in an urban river water, as conducted for this study,...  相似文献   
249.
This study explores the politics of distributive fairness in Locally-Unwanted-Land-Uses (LULUs) siting by looking into how a movement in LULU disputes changes its attitude towards a frame of distributive fairness over a long period of time. Some kinds of facilities are often opposed by local residents because of negative side-effects, even as they are claimed to be necessary for the well-being of the wider public. Framing refers to actors’ signifying work, and how to frame distributive fairness plays a significant role in conflicts over such controversial land uses. In the 23 wards of Tokyo, distributive fairness in waste disposal among the wards has been a crucial issue. In the early 1970s, Koto Ward, which suffered a disproportionate burden of waste disposal, launched a campaign to rectify the unfairness. In-Ward Waste Disposal (IWWD), a frame of distributive fairness, played a central role in this movement. However, Koto Ward’s attitude towards this frame of distributive fairness changed over time. By examining why Koto Ward’s advocacy for IWWD varied over time, this study shows how Koto Ward’s stance on IWWD changed in conjunction with economic, policy, and political circumstances, thereby illuminating the importance of integrating socio-politico-economic contexts in framing analysis.  相似文献   
250.
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