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41.
Natural ventilation is one of the most effective techniques for cooling. Its potential for cooling may be assessed by using a method based on the indoor–outdoor temperature difference of the free-running building, the adaptive comfort criteria and the outdoor temperature. It is demonstrated that the free-running temperature may be used instead of the balance temperature in energy estimation methods. The indoor–outdoor temperature difference of the free-running building becomes a characteristic of the thermal behavior of the building which is decoupled from comfort range and outdoor temperature. A measure related to the energy saved and the applicability of free-cooling is given by the probabilistic distribution of the degree-hours as a function of the outdoor temperature and time. Weather data for this method are available in public domain from satellite investigation. The method can be applied when buildings similar to existing ones are constructed in a new location, when existing buildings are retrofitted or when completely new buildings are designed. The method may be used to interpret the results of building simulation software or of the field measurements. 相似文献
42.
Norma Graf Francesco Albertini Tristan Petit Erik Reimhult Janos Vörös Tomaso Zambelli 《Advanced functional materials》2011,21(9):1666-1672
Triggered release of an entrapped dye from vesicles embedded in a polyelectrolyte multilayer (PEM), as a consequence of the electrochemically induced local pH change in the vicinity of the electrode, is reported. The PEM was deposited on an indium tin oxide (ITO) electrode wherein lipid vesicles filled with a fluorescent dye were embedded. The use of vesicles with a strong negative charge and the polyelectrolyte species of the PEM matrix with a polycation as topmost layer enabled the generation of a stable layer of liposomes in the PEM. 相似文献
43.
Richardson GM Wilson R Allard D Purtill C Douma S Gravière J 《The Science of the total environment》2011,409(20):4257-4268
Dental amalgam is 50% metallic mercury (Hg) by weight and Hg vapour continuously evolves from in-place dental amalgam, causing increased Hg content with increasing amalgam load in urine, faeces, exhaled breath, saliva, blood, and various organs and tissues including the kidney, pituitary gland, liver, and brain. The Hg content also increases with maternal amalgam load in amniotic fluid, placenta, cord blood, meconium, various foetal tissues including liver, kidney and brain, in colostrum and breast milk.Based on 2001 to 2004 population statistics, 181.1 million Americans carry a grand total of 1.46 billion restored teeth. Children as young as 26 months were recorded as having restored teeth. Past dental practice and recently available data indicate that the majority of these restorations are composed of dental amalgam.Employing recent US population-based statistics on body weight and the frequency of dentally restored tooth surfaces, and recent research on the incremental increase in urinary Hg concentration per amalgam-filled tooth surface, estimates of Hg exposure from amalgam fillings were determined for 5 age groups of the US population.Three specific exposure scenarios were considered, each scenario incrementally reducing the number of tooth surfaces assumed to be restored with amalgam. Based on the least conservative of the scenarios evaluated, it was estimated that some 67.2 million Americans would exceed the Hg dose associated with the reference exposure level (REL) of 0.3 μg/m3 established by the US Environmental Protection Agency; and 122.3 million Americans would exceed the dose associated with the REL of 0.03 μg/m3 established by the California Environmental Protection Agency.Exposure estimates are consistent with previous estimates presented by Health Canada in 1995, and amount to 0.2 to 0.4 μg/day per amalgam-filled tooth surface, or 0.5 to 1 μg/day/amalgam-filled tooth, depending on age and other factors. 相似文献
44.
The paper explores the potential uses of parametric modeling to embed construction and structural design knowledge in the form of generative rules and feedback rule-checking functions. The goal of the research reported here is to relate knowledge regarding constructive and structural principles during conceptual design in order to improve early decision-making. For that purpose we have developed a series of functions to guide conceptual design exploration by providing timely evaluation of design alternatives. The research focuses on load-bearing concrete masonry walls, and on basic requirements for doubly curved walls as a design case study. The research extends the Building Object Behavior methodology developed by Lee and others to elucidate, translate and implement design expertise into parametric rules and behaviors. The paper introduces the methodology in the context of a prototype modeling tool for early-stage design of concrete masonry walls and discusses the implications of a parametric modeling approach for conceptual design and collaboration. 相似文献
45.
P Milochau B Talarmin Y Le Ru G Allard P Plantin 《Canadian Metallurgical Quarterly》1997,124(9):612-614
INTRODUCTION: Pyomyositis are relatively rare in our countries. CASE REPORT: A 73-year-old-man presented with leg pains and septicemia. Diagnosis of pyomyositis was made and a large incision was performed after which the patient had a progressive improvement. DISCUSSION: Diagnosis of pyomyositis may be difficult in early stages. Diagnosis is greatly facilitated by magnetic resonance imaging. Responsibility of Staphylococcus aureus in cases of pyomyositis due to methi-resistant Staphylococcus aureus may be evocated even if patients was not hospitalized. 相似文献
46.
This prospective study was designed to assess the prognostic value of tumor-associated antigens, designated 19A211, M344, T138, and T43, with respect to recurrence of primary superficial bladder cancer. Between September 1990 and April 1992, all patients with primary superficial bladder tumors treated by endoscopic resection in 15 participating hospitals were enrolled. Immunostaining for 19A211 and M344 was performed on paraffin-embedded material, and for T43 and T138 on frozen tissue. Antigenic expression was evaluated blindly by a single pathologist. Patients were followed up with the standard schedule of control cystoscopies. Cox regression was used to estimate hazard ratios (HRs) for first recurrence, and Poisson regression was used to estimate recurrence rate ratios and tumor rate ratios adjusted for primary tumor characteristics. By March 1994, 2254 follow-up cystoscopies had been performed on 368 of the 382 study patients, and tumor recurrence was detected in 55.7% of patients. Positivity to 19A211 was detected in 90% of primary tumors, its expression being associated with a decrease in first recurrence hazard ]HR, 0.65; 95% confidence interval (CI), 0.42-1.03] and in recurrence rate (recurrence rate ratio, 0.70; 95% CI, 0.53-0.92). Positivity to T138 was detected in 15% of tumors, and its expression was associated with an increase in first recurrence hazard (HR, 1.43; 95% CI, 0.92-2.22) and in recurrence rate (recurrence rate ratio, 1.31; 95% CI, 1.00-1.72). Positivity to M344 was detected in 71% of tumors, and its expression was associated with an increase in tumor rate (tumor rate ratio, 1.77; 95% CI, 1.41-1.97). T43 expression was not associated with recurrence end points. In conclusion, recurrence of superficial bladder cancer was associated with antigenic expression of 19A211, T138, and M344, independently of primary tumor characteristics. 相似文献
47.
A new concept for infrared imaging using a pixelless photon frequency up-conversion device together with a CCD array is presented. The concept is applicable to wavelengths longer than the CCD response range (longer than about 1.1 μm). Preliminary imaging results using a quantum well infrared photodetector integrated with a light emitting diode are also presented 相似文献
48.
There is an increasing need for heat- and flame-resistant fibres. Among these fibres a new class has been developed under the trademark Kermel: the aromatic Polyamide-Imides. Different methods of polymer preparation are reviewed. A direct polycondensation process in polar solvents is described, starting from trimellitic anhydride and aromatic diisocyanates. The inherent viscosity and the mechanical pr?operties of the corresponding fibres depend strongly on the solvent, the diisocyanate and eventually another difunctional comonomer. The fibres prepared by dry or wet spinning processes are characterized by a high level of heat and flame-resistance together with good textile properties, as compared with other fibers. In relation to their inherent properties, the main applications are the highly safe professionnal protective clothing, non flammable furnishings and some other technical applications. 相似文献
49.
50.
Cossé AA Bartelt RJ Zilkowski BW Bean DW Petroski RJ 《Journal of chemical ecology》2005,31(3):657-670
The leaf beetle Diorhabda elongata Brullé (Coleoptera: Chrysomelidae)has been introduced as a biological control agent for saltcedars, Tamarix spp., an exotic, invasive weedy tree in the western United State. Gas chromatographic (GC) analysis of volatiles collected from feeding male or female beetles, or saltcedar foliage alone, showed two components produced almost exclusively by males. These compounds elicited responses from antennae of male and female beetles in GC-electroantennographic detection (EAD) analyses. The compounds were identified as (2E,4Z)-2,4-heptadienal (1) and (2E,4Z)-2,4- heptadien-1-ol (2) by GC-mass spectrometry (MS), and confirmed with authentic standards. The two compounds were also detected at trace levels from feeding females and foliage controls, but the amounts from feeding males were 8-40 times higher, typically 55-125 ng per day per male. The amounts of 1 and 2 in collections from females did not differ significantly from amounts collected from control foliage. In field trials, 2 as a single component was as attractive as a 1:1 blend of 1 and 2. Compound 1 as a single component was more attractive than controls, but much less attractive than 2 or the blend. Males and femaleswere attracted in about equal numbers, indicating that this is an aggregation pheromone.Mention of trade names or commercial products in this article is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the U.S. Department of Agriculture. 相似文献