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Unlike the residential building stock, most countries have poor information on their non-domestic stock. This necessitates the use of other data sources. In the mid-1980s the (then) New Zealand Department of Valuation digitized its valuation records. This permitted the first analysis of an entire country's non-domestic buildings. A very long-tail probability density function was identified, with the largest 5% of buildings containing more than 40% of the floor space. This knowledge informed the development of research for understanding non-domestic buildings as well as underpinning the 1996 revision of the NZ Building Code Clause H1 Energy Efficiency. More recently an analysis of valuation data has provided the Building Energy End-use Study (BEES) with a national sampling frame to examine energy and water end-uses in non-domestic buildings. The development of processes for collecting and analyzing data is described. Considerable changes in understanding of valuation data have occurred for documenting the non-domestic building stock. New online and geographic information sources can validate and improve building data. The use of such a database supports improved understanding of the changing nature of the building stock and potential intervention points, as well as harnessing regulatory and market forces. 相似文献
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Synthetic Crystals of Silver with Carbon: 3D Epitaxy of Carbon Nanostructures in the Silver Lattice 下载免费PDF全文
Lourdes G. Salamanca‐Riba Romaine A. Isaacs Melburne C. LeMieux Jiayu Wan Karen Gaskell Yeping Jiang Manfred Wuttig Azzam N. Mansour Sergey N. Rashkeev Maija M. Kuklja Peter Y. Zavalij Jaime R. Santiago Liangbing Hu 《Advanced functional materials》2015,25(30):4768-4777
Only minimum amounts of carbon can be incorporated into silver, gold, and copper in a thermodynamically stable form. Here, the structure of stable silver carbon alloys is described, which are produced by thermoelectrically charging molten silver with carbon ions. Transmission electron microscopy and Raman scattering are combined to establish that large amount of carbon is accommodated in the form of epitaxial graphene‐like sheets. The carbon bonds covalently to the silver matrix as predicted from density functional theory (DFT) calculations with bond energies in the range 1.1–2.2 eV per atom or vacancy. Graphitic‐like sheets embedded in the crystal lattice of silver form 3D epitaxial structures with the host metal with a strain of ≈13% compared to equilibrium graphene. The carbon nanostructures persist upon remelting and resolidification. A DFT‐based analysis of the phonon density of states confirms the presence of intense vibration modes related to the Ag? C bonds observed in the Raman spectra of the alloy. The solid silver–high carbon alloy, termed “Ag‐covetic,” displays room temperature electrical conductivity of 5.62 × 107 S m?1 even for carbon concentrations of up to ≈6 wt% (36 at%). This process of incorporation of carbon presents a new paradigm for electrocharging assisted bulk processing. 相似文献
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AD Gribble RJ Ife A Shaw D McNair CE Novelli S Bakewell VP Shah RE Dolle PH Groot N Pearce J Yates D Tew H Boyd S Ashman DS Eggleston RC Haltiwanger G Okafo 《Canadian Metallurgical Quarterly》1998,41(19):3582-3595
A series of (3R,5S)-omega-substituted-3-carboxy-3, 5-dihydroxyalkanoic acids have been synthesized and evaluated as inhibitors of the recombinant human form of ATP-citrate lyase. The best of these have Ki's in the 200-1000 nM range. As the corresponding thermodynamically favored gamma-lactone prodrugs, a number of compounds are able to inhibit cholesterol and fatty acid synthesis in HepG2 cells and reduce plasma triglyceride levels in vivo. The best of these, compound 77, is able to induce clear hypocholesterolemic and hypotriglyceridaemic responses when administered orally to rat and dog. These results provide evidence to support the hypothesis that compounds which inhibit ATP-citrate lyase have the potential to be a novel class of hypolipidemic agent, which possess combined hypocholesterolemic and hypotriglyceridemic activities. 相似文献
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JS Starreveld MJ Kroos JD Van Suijlen CE Verrijt HG Van Eijk JP Van Dijk 《Canadian Metallurgical Quarterly》1995,16(4):383-395
The present study aims at the role of ferritin in the regulation of syncytiotrophoblast free iron levels. The differentiated cytotrophoblast cell in culture is used as a model for this maternal-fetal interface. Cytotrophoblast cells isolated from term placentae are cultured in iron-poor (Medium 199), iron-depleted [desferrioxamine(DFO)] and iron-supplemented [diferric transferrin (hTF-2Fe), ferric ammonium citrate (FAC)] medium. Distribution and de novo synthesis of isoferritins is studied, together with the cellular iron concentration and the ferritin iron saturation. Compared to ferritin isolated from total placenta, ferritin obtained from villous tissue is enriched with acidic isoforms. This observation is in agreement with measured light (L) to heavy (H) subunit ratios < 1 of de novo synthesized ferritin in cultured cytotrophoblast cells. Neither iron-poor culture medium, nor hTf-2Fe supplemented medium affects the cellular iron or ferritin concentration. FAC increased the cellular ferritin iron saturation and (by synthesis) the acidic isoferritin concentrations. The results strongly suggest, that the term syncytiotrophoblast is able to balance transferrin-mediated iron uptake and iron release. In case of FAC supplementation, the syncytiotrophoblast is unable to keep intracellular iron low, and ferritin synthesis is stimulated. The predominance of acidic ferritins and the preferential synthesis of H subunits can be functionally explained by the established fact that iron incorporation in acidic ferritins is faster due to the presence of ferroxidase centres. Damage by free iron catalysed hydroxyl radical formation is therefore minimized. 相似文献
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CE De Laet BA Van Hout H Burger AE Weel A Hofman HA Pols 《Canadian Metallurgical Quarterly》1998,13(10):1587-1593
The aim of our study was to validate a hip fracture risk function, composed of age and femoral neck bone mineral density (BMD). This estimate of the 1-year cumulative risk was previously developed on the basis of Dutch hip fracture incidence data and BMD in men and women. A cohort of 7046 persons (2778 men) aged 55 years and over was followed for an average of 3.8 years. The 1-year hip fracture risk estimate was calculated for each participant according to the risk function and categorized as low (<0.1%), moderate (0.1 to < 1%), or high (> or =1%). Observed first hip fracture incidence was then analyzed for each of these risk categories by age and gender. Additionally, we calculated the relative risk per standard deviation (SD) decrease in femoral neck BMD in this population. At baseline, 2360 individuals were categorized as low risk, 2567 as moderate risk, and 378 as high risk During follow-up, 110 first hip fractures were observed corresponding to an incidence rate of 4.1/1000 person-years (pyrs) (95% confidence interval 3.4-5.0). The observed incidence rate in the low risk group was 0.2/1000 pyrs (0.1-0.9), 2.7/1000 pyrs (1.8-3.9) in the moderate risk group, and 18.4/1000 pyrs (12.4-27.2) in the high risk group. Below the age of 70 years, incidence was low in all categories, and very few individuals were considered at high risk Above the age of 70 years, the observed incidence was high in the high risk group, while in the low and moderate risk groups, the incidence remained low even over 80 years of age. In women, the age-adjusted relative risk for hip fractures was 2.5 per SD decrease in femoral neck BMD (1.8-3.6), while in men this relative risk was 3.0 per SD (1.7-5.4). In conclusion, we observed a similar relation of hip fracture with femoral neck BMD in men and women and were able to predict accurately hip fracture rates over a period of almost 4 years. 相似文献