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101.
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The development of new tanning agents and new technologies in the leather sector is required to cope with the increasingly higher environmental pressure on the current tanning materials and processes such as tanning with chromium salts. In this paper, the use of titanium wastes (cuttings) resulting from the process of obtaining highly pure titanium (ingots), for the synthesis of new tanning agent and tanning bovine hides with new tanning agent, as alternative to tanning with chromium salts are investigated. For this purpose, Ti waste and Ti-based tanning agent were characterized for metal content by inductively coupled plasma mass spectrometry (ICP-MS) and chemical analysis; the tanned leather (wet white leather) was characterized by Scanning Electron Microscope/Energy Dispersive Using X-ray (Analysis). SEM/EDX analysis for metal content; Differential scanning calorimetric (DSC), Micro-Hot-Table and standard shrinkage temperature showing a hydrothermal stability (ranged from 75.3 to 77 °C) and chemical analysis showing the leather is tanned and can be processed through the subsequent mechanical operations (splitting, shaving). On the other hand, an analysis of major minor trace substances from Ti-end waste (especially vanadium content) in new tanning agent and wet white leather (not detected) and residue stream was performed and showed that leachability of vanadium is acceptable. The results obtained show that new tanning agent obtained from Ti end waste can be used for tanning bovine hides, as eco-friendly alternative for chrome tanning.  相似文献   
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Static and dynamic adsorption studies of Co (II) ions have been undertaken at fixed pH and ionic strength taking binary biopolymeric beads of cross-linked calcium alginate and carboxy methylcellulose as biosorbents. The adsorption data were applied to Langmuir and Freundlich isotherm equations and various static parameters were calculated. The dynamic nature of adsorption process was quantified in terms of several kinetic constants such as rate constants for adsorption (K) and Lagergreen rate constant (K ad). The influence of various experimental parameters such as solid-to-liquid ratio, pH, and temperature, the presence of salts and chemical composition of biopolymeric beads were investigated on the adsorption of cobalt ions.  相似文献   
105.
This paper criticises the conclusions and the unanswered questions in the National Institute of Standards and Technology (NIST)'s official report on the evacuation of the World Trade Center in New York City, United States, on 11 September 2001. It reviews the extent to which the report disregards several conventional statistical methods and comments on the NIST's refusal to share the machine‐readable data file with the scientific community for replication and further analysis. Problems lie in the sampling methods employed, the treatment of missing data, the use of ordinary least squares (OLS) with binary dependent variables, the failure to document the scalability of the scales used, the lack of tests to check for constant error variance, and the absence of overall fit tests of the model. There are also conceptual and theoretical issues, such as the absence in the report of considerations of the influence of group‐level processes and their impact on the collective behaviour of evacuating collectivities.  相似文献   
106.
This study investigates the factors determining an individual's response to official recommended protective measures, based on the Health Belief Model and the Protective Action Decision Model, to understand the adoption of protective behaviour during an H7N9 (Avian Influenza A) emergency. A public survey involving 1,375 respondents was conducted in Anhui Province, China, during the 2013 H7N9 outbreak to test the research model and hypotheses. The results indicate that protective, stakeholder, and risk perceptions influence positively an individual's willingness to take recommended actions. Protective and stakeholder perceptions also have a positive bearing on lay people's risk perceptions. A stakeholder perception is a vital determinant of a protective perception. More importantly, the effects of protective and stakeholder perceptions on behavioural responses to recommendations are mediated in part by risk perception. These findings can help public health officials to develop messages to encourage members of the population to protect themselves effectively during an influenza crisis.  相似文献   
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108.
The main constraints on energy exploration in the Australian arid zone are logistic, with limited additional constraints from Aboriginal reserves. The main consequence is increased access, with possible introduction of weeds and expansion of tourism and cattle grazing in consequence.  相似文献   
109.
In regulatory practice, the principle of precaution is hardly linked to the ideal of sustainable development. In this article, we argue that it should be. We argue that sustainable development is the sense of an ethics of co-responsibility, while precaution is the attitude needed to realize this sense. From this perspective, we comment on some regulatory practices within the European context regarding authorization requests for deliberate releases of genetically modified crops and show some problems that are popping up there, for example, the difficulties in interpreting the meaning of harm” (and of benefit”), the symptomatic gap between regulatory rule and political practice. Finally, we suggest that, in order to respond to such problems, precaution should find an appropriate translation in the fields of both research and innovation policy, of authorization policy and of economic policy.  相似文献   
110.
A methodology for the long-term assessment of prices is designed and applied to the international markets for coal, oil and natural gas and likely price developments between 1990 and 2000 are explored. The coal market will remain competitive, and the long-term price will be determined by the total cost of marginal supply. The oil price will be set, even in the long term, substantially above the competitive level, by those who control the exceptional Middle East resource base. The traditional link between gas and oil prices will erode in the 1990s, and gas will be independently and competively priced by the turn of the century. Resource constraints are not expected to push prices upwards within the time horizon of the study. The relative price of gas will fall over the forecast period, and its market share will increase as a consequence.  相似文献   
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