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Eco-driving has been proposed as an approach to significantly reduce greenhouse gas emissions arising from personal automobile use. Eco-driving is the adoption of a measured driving style, minimising unnecessary breaking and aggressive acceleration. Eco-driving can be seen as a low cost and immediate approach to emission reduction as it involves the modification of drivers’ behaviours as opposed to the development and implementation of newer, more efficient technology. Despite the proposed benefits of eco-driving, numerous challenges are faced in order to encourage the adoption of these behaviours and maintain them long term. This narrative review presents the concept of eco-driving, with a focus on the long-term maintenance of these behaviours, including training programmes and feedback devices. It is clear within current literature that, despite the economic and environmental benefits of adopting eco-driving, drivers require feedback on their actions in order to promote long-term, behavioural, change. 相似文献
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In many areas of Northern and Western Alaska, small streams and shallow lakes serve as community raw water supplies. These water supplies freeze completely during winter. In order to supply drinking water during the 6–9 month winter, communities store water that was treated during summer. A chlorine residual is maintained in the stored water. Raw water sources derived from surface water may be heavily laden with dissolved organic matter. At utilities where organic matter escapes treatment, the potential for accumulation of disinfection by-products (DBPs) during storage is a significant health concern. The following study was performed to evaluate this potential threat. Water was collected from five operating utilities, four that normally store water for 6–9 months and one that produces drinking water year-round. Raw, filtered (i.e., unchlorinated) and “finished” (i.e., filtered and chlorinated) water samples were collected during the summer pumping season and stored in the laboratory for 8 months. In order to mimic practice in the field, the chlorine residual was maintained in the finished water for the full storage period. While the concentration of DBPs in the finished water varied over the study period, there was not a statistically significant trend from the third to the eighth month of storage. The observed DBP values were strongly a function of the type of treatment system used. Those systems passing more organic matter had higher DBP values throughout the storage period. The ultraviolet absorbance at 254 nanometers ?start(UV254)end? decreased continuously in the finished water coincident with chlorine consumption. ?startUV254end?, often used as a surrogate for DBPs, remained constant during the entire storage periodin raw and filtered water samples. Filtered water that was stored prior to chlorination accumulated fewer DBPs than finished water that was continuously chlorinated during the storage period. This result suggests that storing filtered water instead of finished water for long periods would limit DBP exposure to consumers. This conclusion was based on a comparison of DBP formation potentials (i.e., raw and filtered water) to DBPs (i.e., finished water). It is important to note that DBP formation potentials are based on a ?start24?hend?chlorine contact time. If long term storage were provided for filtered water, a smaller volume of secondary storage would still be needed to provide contact time for disinfection. 相似文献
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IS Varga B Matkovics DQ Hai M Kotormán T Takács M Sasvári 《Canadian Metallurgical Quarterly》1997,85(2):129-138
The World Wide Web-based form is a promising method for the construction of an on-line data collection system for clinical and epidemiological research. It is, however, laborious to prepare a common gateway interface (CGI) program for each project, which the World Wide Web server needs to handle the submitted data. In medicine, it is even more laborious because the CGI program must check deficits, type, ranges, and logical errors (bad combination of data) of entered data for quality assurance as well as data length and meta-characters of the entered data to enhance the security of the server. We have extended the specification of the hypertext markup language (HTML) form to accommodate information necessary for such data checking and we have developed software named AUTOFORM for this purpose. The software automatically analyzes the extended HTML form and generates the corresponding ordinary HTML form, 'Makefile', and C source of CGI programs. The resultant CGI program checks the entered data through the HTML form, records them in a computer, and returns them to the end-user. AUTOFORM drastically reduces the burden of development of the World Wide Web-based data entry system and allows the CGI programs to be more securely and reliably prepared than had they been written from scratch. 相似文献
77.
A program to demonstrate high temperature hyperfiltration to renovate hot industrial wastewater for direct recycle is in Phase 2; the installation of a ~10m /hr membrane system to achieve closed cycle operation of a textile dye range. Hydrous-zirconium oxide-polyacrylate (ZOPA) membranes dynamically formed on porous sintered stainless steel tubes arranged in a Single Pass system will be supplied by the Mott-Brandon Corporation. Phase I of the program involved on-site pilot testing of several membranes, the procurement of competitive bids for the membrane system and the complete installation including all interface controls required for the dye operation.The 180°F (82°C) dye wash water contains residual dyes, auxiliary detergent and wetting agents, and guar gum. The total solids in the wash water range from 130 to 7000mg/l with the suspended solids ranging from 2 to 90 mg/l. The membrane system will be operated at 96% recovery. The concentrated residue is being studied for reuse or ultimate disposal through evaporation and/ or incineration. The performance of the membranes during the pilot tests, the laboratory evaluation of the reuse, and the complete recovery system are described. 相似文献
78.
采用钛盐光度法测定O3/H2O2系统中的/H2O2,考察了pH值、O3/H2O2摩尔比、钛盐用量和显色时间的影响,确定了最佳的测定条件;通过加标回收率实验和对比实验,证明了该方法的可靠性.结果表明,pH值为3.0、λ=385nm、草酸钛钾浓度2.5mmol·L-1和显色时间8min条件下,H2O2浓度0~45mg·L-... 相似文献
79.
Yunxia Yang Craig M. Brown Chunxia Zhao Alan L. Chaffee Burke Nick Dongyuan Zhao Paul A. Webley Jacob Schalch Jason M. Simmons Yun Liu Jae-Hyuk Her C.E. Buckley Drew A. Sheppard 《Carbon》2011,(4):1305-1317
Ordered microporous carbons containing dispersed platinum nanoparticles were fabricated and chosen as suitable models to investigate micro-structure development and hydrogen transport properties of zeolite-templated carbons. X-ray photoelectron spectroscopy analysis revealed that the enhanced heat of adsorption is related to the narrow micro-channels templated from the zeolite and the presence of certain CO groups on the carbon. The lack of a well-defined and intense rotational transition line and the persistent broad H2 recoil spectrum in neutron scattering results suggests a distribution of binding sites. Most interestingly, hydrogen diffusion occurs on two time scales, consisting of a fast liquid-like jump diffusion on the timescale of picoseconds along with an even faster bulk-like diffusion. The liquid-like motion is characterized by a diffusion constant of (2.1 ± 0.3) × 10−8 m2/s with an activation energy of ca. 77 K; both values indicate somewhat lower mobility than similar dynamics of H2 on nanotubes, activated carbon XC-72, or Grafoil, yet greater mobility than that of bulk liquid. These unusual characteristics for hydrogen in carbons are believed to arise from the network of narrow pores in this zeolite-templated image of the zeolite. In fact, the diffusion constants of the templated carbons are extremely similar to those measured for zeolite 13X. 相似文献
80.
Craig Frear Zhi‐Wu Wang Chenlin Li Shulin Chen 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(1):145-152
BACKGROUND: There remain technological deficiencies in the economical anaerobic digestion of the entire flow of flushed dairy manure on farms within cold climates. In order to develop an anaerobic digester tailored for this purpose, this study investigated the distributions of biomass and biogas generated in three particle‐size‐characterized zones of flushed dairy manure. RESULTS: Results demonstrate that comparable biogas generations are equally distributed between the solids and liquid phases of flushed dairy manure, implying that at least 50% of methane generation might be lost when utilizing existing processes that only selectively handle the liquid or solids phases. Microscopic and kinetic studies show that the majority of microorganisms in the manure are attached to the surface of undigested dairy manure fibrous solids. In particular, greater than 70% of acetate‐utilizing methanogens were found closely associated with the indigestible solids. This high microbial affinity to the dairy manure solids phase can be traced back to the selection pressure driven bacterial immobilization mechanism in cattle rumen. CONCLUSION: This study shows that dairy manure fibrous solids have the potential to act as effective natural biomass carriers for high rate and simultaneous methanation of both solids and liquid phases of flushed dairy manure in one digester. Copyright © 2010 Society of Chemical Industry 相似文献