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851.
Environmental Science and Pollution Research - Tetracycline hydrochloride (TCH) electro-oxidation by commercial DSA® and commercial DSA® modified by platinum electrodeposition was...  相似文献   
852.
The <8 mm fraction of aged incinerator bottom ash from a commercial incinerator (energy from waste) plant has been collected at regular intervals, characterised and processed to form ceramic materials. Ashes were sieved, wet ball milled, dried, compacted and sintered at temperatures between 1080 and 1115 degrees C. Variations in the chemical composition and mineralogy of the milled ash, and the mineralogy, physical properties and leaching of sintered products have been assessed. Milling produces a raw material with consistent chemical and mineralogical composition with quartz (SiO(2)), calcite (CaCO(3)), gehlenite (Ca(2)Al(AlSi)O(7)) and hematite (Fe(2)O(3)) being the major crystalline phases present. Different batches also milled to give consistent particle size distributions. Sintering milled incinerator bottom ash at 1110 degrees C produced ceramics with densities between 2.43 and 2.64 g/cm(-3) and major crystalline phases of wollastonite (CaSiO(3)) and diopside (CaMgSi(2)O(6)). The sintered ceramics had reduced acid neutralisation capacity compared to the as-received ash and exhibited reduced leaching of Ca, Mg, Na and K under all pH conditions. The leaching of heavy metals was also significantly reduced due to encapsulation and incorporation into glassy and crystalline phases, with Cu and Al showing greatly reduced leaching under alkali conditions.  相似文献   
853.
854.
The objective of this study was to identify the relative importance of culturally relevant professional problems and the degree of control over them, as perceived by dentists and dental students in Mexico City, Mexico. The dentists and students ranked 13 problems according to importance and then according to the perceived degree of control over each one. Novice clinicians were less secure about their ability to cope with the legal, financial, and clinical performance problems, whereas experienced clinicians were more concerned about occupational hazards and the dental market and culture. Both reported similar perceptions of their control of the problems. This preliminary information should support introducing into dental schools relevant practice-management courses, targeting continuing education efforts, and instituting professional counseling measures to meet the challenges posed by these problems.  相似文献   
855.
Background. Pathogens can be transmitted to health professionals after contact with biological material. The exact number of infections deriving from these events is still unknown, due to the lack of systematic surveillance data and under-reporting. Methods. A cross-sectional study was carried out, involving 451 nursing professionals from a Brazilian tertiary emergency hospital between April and July 2009. Through an active search, cases of under-reporting of occupational accidents with biological material by the nursing team were identified by means of individual interviews. The Institutional Review Board approved the research project. Results. Over half of the professionals (237) had been victims of one or more accidents (425 in total) involving biological material, and 23.76% of the accidents had not been officially reported using an occupational accident report. Among the under-reported accidents, 53.47% were percutaneous and 67.33% were bloodborne. The main reason for nonreporting was that the accident had been considered low risk. Conclusions. The under-reporting rate (23.76%) was low in comparison with other studies, but most cases of exposure were high risk.  相似文献   
856.
857.
Environment, Development and Sustainability - In order to adequately assess energy policies and set clear objectives, a key preliminary step is to know the energy use patterns of the different...  相似文献   
858.
Environment, Development and Sustainability - This paper evaluates compliance with environmental laws in the municipality of Sorriso and the impact of changing legislation on vegetation. To verify...  相似文献   
859.
Environment, Development and Sustainability - The increasing mortality of COVID-19 can aggravate soil contamination by metals, harmful to the health of the population, requiring new projects for...  相似文献   
860.
Service quality in a construction technology laboratory can result in an improvement in construction companies’ competitiveness. This research aims to evaluate the service quality provided by a construction technology laboratory, specifically in the segment of performing testing through the rupturing of concrete samples. For this research, a survey was conducted using a structured questionnaire that was created based on a literature review regarding the surveying of laboratory customers at a university in the south of Brazil. Our research was both exploratory and quantitative, and the data were analyzed by applying multivariate data analysis. The conclusions of this study show that the dimensions of quality services are: communication, reliability, responsiveness, credibility, and tangibility. These five dimensions together provide a high explained variance standard of 79.75%. Having a suitable number of attendants available to serve customers and presenting agility in the construction laboratory is one of the managerial research contributions. Moreover, through information availability, this research generates greater traceability that can be used both by customers and by institutional management. Constantly and thoroughly monitoring the customer service cycle is another relevant factor that can improve the quality of the services provided.  相似文献   
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