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81.
The complex procurement process entailed by the private finance initiative (PFI) means that clients need new capacities to manage their relationships with bidders and to assess project proposals if the desired level of design quality is to be achieved. To assist local authorities in their client role, a new Architectural Design Quality Evaluation Tool was developed. The aim was to improve the quality of design in residential sheltered housing, procured through the PFI. The tool was developed for and applied to a programme that will see the replacement of a local authority's entire sheltered housing stock. The tool has two functions: (1) to inform the client's assessment process and assist with the selection of the preferred bidding consortium through a series of stages in the PFI process; and (2) to improve the quality of all the submitted designs through an iterative process. Although several existing mechanisms are available for evaluating the performance attributes of buildings, few also tackle the less tangible amenity attributes, which are vital to the feeling of home. The new tool emphasizes the amenity attributes without neglecting performance.  相似文献   
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How green is my river? A new paradigm of eutrophication in rivers   总被引:4,自引:0,他引:4  
Although the process of eutrophication is reasonably well understood in lakes, there is currently no conceptual understanding of how eutrophication develops in rivers. This issue is addressed here. A review of the main processes controlling the development of eutrophication in lakes has been carried out as a precursor to considering the effect in rivers. The importance of hydraulic flushing in controlling algal growth suggests that short-retention-time rivers will show different effects compared to long retention-time, impounded rivers. The latter are likely to operate like lakes, moving from macrophyte domination to phytoplankton domination whereas the former move to benthic and filamentous algal domination. Subsequently, a conceptual model of the development of eutrophic conditions in short-retention-time rivers is developed. Although there is general agreement in the literature that an increase in nutrients, particularly phosphorus, is a pre-requisite for the eutrophic conditions to develop, there is little evidence in short-retention-time rivers that the plant (macro and micro) biomass is limited by nutrients and a good case can be made that the interaction of hydraulic drag with light limitation is the main controlling factor. The light limitation is brought about by the development of epiphytic algal films on the macrophyte leaves. The implications of this conceptual model are discussed and a series of observable effects are predicted, which should result if the model is correct.  相似文献   
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The objective was to characterize and associate the receptor reactivities of fibroblastic growth factor (FGF)‐2, FGF‐7, FGF‐8, epidermal growth factor (EGF), α‐actin and vimentin in relation to the androgen receptor (AR), α and β estrogen receptors (ERα and ERβ), and prolactin receptor in the prostate of elderly men showing low‐ and high‐grade adenocarcinoma. Thirty prostatic samples were taken from 60‐ to 90‐year‐old patients without prostatic lesions and with low‐grade cancer and high‐grade cancer, from the University Hospital, School of Medicine, the State University of Campinas. The results showed that increased FGF‐2, FGF‐7, and FGF‐8 receptor reactivities and decreased AR reactivity were verified in both high‐ and low‐grade cancer. However, the FGF‐8 receptor showed greater involvement at the beginning of the malignancy alterations. Increased EGF receptor (EGFR) reactivity and diminished α‐actin immunohistochemistry were identified in both cancer groups. Also, increased ERα, PR, and vimentin receptors were verified in both cancer groups. To conclude, the ERα involvement in the reactive stroma activation led to a microenvironment, which was favorable to cancer progression, due to maximizing stromal imbalance. The prolactin could be related to cancer progression due to its interaction with ERα action, indicating that this hormone could be a relevant target to prevent the estrogenic effects in the prostatic lesions. Both FGF receptor (FGFR)‐2 and FGFR‐8 play a fundamental role in the early stages of prostate cancer, suggesting that these molecules could be a promising therapeutic target. The differential localization of the fibroblastic factors between the prostatic epithelium and stroma of elderly men, who presented prostate cancer, could indicate a favorable distinction for tumoral progression. Microsc. Res. Tech. 76:321–330, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
87.
A capillary viscometer was used to measure viscosity as a function of pressure, temperature, and shear stress for a number of lubricants. Measurements were made at 38 C, 99 C, and 149 C (100 F, 210 F, and 300 F), gauge pressure to 5.5 × 108 N/m2 (8 × 104 psi), and shear stresses to 106 N/m2 (14.5 psi). At 38 C (100 F), the order of the pressure-viscosity coefficients for the unformulated fluids was: fluorinated polyether > synthetic hydrocarbon > naphthenic mineral oil > synthetic paraffinic oil (lot 4) > C-ether ? synthetic paraffinic oil (lot 3) > polyalkyl aromatic > advanced ester. All pressure viscosity coefficients decreased with increasing temperature. Fair agreement was obtained when pressure-viscosity coefficients at 38 C (100 F) and 6.9 × 107 N/m2 (104 psi) were compared to data from other investigators using different techniques (optical elastohydrodynamics, oscillating crystal, and low shear capillary viscometry).  相似文献   
88.
Many of today's spaceraft have long mission lifetimes. Whatever the lubrication method selected, the initial lubricant charge is required to last the entire mission. Fluid lubricant losses are mainly due to evaporation, tribo-degradation, and oil creep out of the tribological regions.

In the past, several techniques were developed to maintain the appropriate amount of oil in the system. They were based on oil reservoirs (cartridges, impregnated porous parts), barrier films, and labyrinth seals. Nevertheless, all these systems have had limited success or have not established a proven record for space missions.

The system reported here provides to the ball-race contact fresh lubricant in-situ and on demand when the ball bearing is close to failure. The lubricant is stored in a porous cartridge attached to the inner or the outer ring of a ball bearing. The oil is released by heating the cartridge to eject oil, taking advantage of the greater thermal expansion of the oil compared to the porous network. The heating may be activated by torque increases that signal the depletion of oil in the contact. The low surface tension of the oil compared to the ball bearing material is utilized and the close proximity of the cartridge to the moving balls allows the lubricant to reach the ball-race contacts. This oil re-supply system avoided a mechanism failure, reduced torque to an acceptable level, and extended the life of the component.  相似文献   
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We have combined the use of a molecular beam reactor with ‘fast’ XPS in order to correlate changes in the rate of CO oxidation with the coverages of the adsorbates and intermediates on the surface. In the reactor CO oxidation exhibits an isothermal ‘light-off’ phenomenon in which the rate autocatalytically increases with time. This is due to the desorption of CO which releases extra sites for O2 dissociation which, in turn, removes more CO, and hence the self-acceleration. In effect the reaction can be written as 2COa + O2g + 2S → 2CO2g + 4S, the acceleration coming from the release of extra adsorption sites, S, which are involved in the reaction itself. ‘Fast XPS’, carried out in-situ during the course of the reaction, shows domination of the surface by COa below 390 K and by Oa above that temperature, with a rapid change in surface coverage over a very narrow temperature window. This is an advance on earlier work, since our measurements are made in a single, continuous experiment, due to the high brightness of the synchrotron source. This also allows the data to be obtained at high energy resolution, in the presence of both gases, and without contamination. On high surface area samples this acceleration is further reinforced due to a rapid temperature increase because of the highly exothermic nature of the overall reaction.  相似文献   
90.
Using a 1,3-regioselective lipase as a catalyst, soybean oil and olive oil were interesterified with the short-chain triacylglycerol tributyrin (1,2,3-tributyrylglycerol) to produce mixtures of structured triacylglycerols (SL-TAG). The SL-TAG were purified by column chromatography and analyzed by both normal-phase (silica column; NPSIL) and reversed-phase [octadecyl silane (ODS) column] high-performance liquid chromatography (HPLC). Individual SL-TAG molecular species were detected by evaporative light-scattering detection, and characterized by mass spectrometry. NPSIL HPLC successfully separated the newly synthesized SL-TAG into two groups of TAG: one composed of one butyryl group and two long-chain fatty acyl groups (from soybean or olive oil); the second was composed of two butyryl groups and one long-chain fatty acyl group. The SL-TAG species were further analyzed by reversed-phase HPLC which gave a more detailed separation of the TAG species present in the two SL-TAG.  相似文献   
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