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1.
New relationships between energy efficiency, illuminance uniformity, spacing and mounting height in public lighting installations were derived from the analysis of a large sample of outputs generated with a widely used software application for lighting design. These new relationships greatly facilitate the calculation of basic lighting installation parameters. The results obtained are also based on maximal energy efficiency and illuminance uniformity as a premise, which are not included in more conventional methods. However, these factors are crucial since they ensure the sustainability of the installations. This research formulated, applied and analysed these new equations. The results of this study highlight their usefulness in rapid planning and urban planning in developing countries or areas affected by natural disasters where engineering facilities and computer applications for this purpose are often unavailable. 相似文献
2.
Biosynthesis and purification of histidine‐tagged human soluble catechol‐O‐methyltransferase 下载免费PDF全文
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Production of polyhydroxybutyrate (PHB) of high and ultra‐high molecular weight by Azotobacter vinelandii in batch and fed‐batch cultures 下载免费PDF全文
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对许多需要数安培供电电流的应用而言,三端输出可调线性稳压器有易用.低成本和完全片上过载保护等特点,如美国国家半导体公司的LM317。增加数个元器件可以使三端稳压器具备一种高速度的短路限流能力,从而提高可靠性。限流器可将最大输出电流限制在一个安全的恒定水平IMAX上,避免稳压器的损坏。当出现一个故障状况时,传输晶体管上的功耗近似于VIN×IMAX。要让设计的稳压器能承受过载,就需要谨慎地选择元器件的额定值(经常是留了过大的余地),除非可以在故障发生时降低或折叠(foldback)输出电流。 相似文献
6.
Fernanda de Carvalho Panzeri Pires‐de‐Souza Renata Espíndola Silveira Gabriel Abuna Michelle Alexandra Chinelatti Carla Cecilia Alandia‐Román Mario Alexandre Coelho Sinhoreti 《Microscopy research and technique》2015,78(12):1062-1068
The purpose of this study was to analyze, by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM), the morphology of sealant/enamel interface after surface treatment with Biosilicate. Before pits and fissures sealing, the occlusal surfaces of 10 sound human molars were sectioned perpendicularly at the fissures in order to obtain three slices for each tooth. Slices were randomly assigned into three groups (n = 10) according to sealing protocol: Group 1‐ Acid etching + Biosilicate + glass ionomer‐based sealant (Clinpro XT Varnish, 3M ESPE); Group 2‐ Acid etching + glass ionomer‐based sealant (Clinpro XT Varnish, 3M ESPE); Group 3‐ No sealing. All slices were subjected to thermal cycling (5,000 cycles; 5–55°C; dwell time: 30s). Half of the slices from each group (n = 5) were analyzed by CLSM and the other half by SEM. Groups 1 and 2 were also submitted to EDS analysis and their data were evaluated by Two‐Way ANOVA e Tukey's test (α=5%). EDS data analysis showed higher amounts of silicon (Si) ions than calcium (Ca) ions in Group 1 (P < 0.05); Group 2 presented higher amounts (P < 0.05) of Ca ions than Si ions. It may be concluded that the use of Biosilicate for surface treatment did not affect the morphology of glass ionomer‐based sealant/enamel interfaces. Microsc. Res. Tech. 78:1062–1068, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
7.
Marcelo F. Alfradique Rogério O. EspÓSITO Marcelo Castier 《Chemical Engineering Communications》2013,200(5):657-674
We successfully extended a computer algebra program (Thermath), orginally developed for the automatic computer implementation of physical property calculations, in order to perform the global phase stability test and to generate code for the steady state simulation of multistage separators. Analytical derivatives of the modeling equations and of the thermodynamic properties were rapidly obtained and automatically implemented in Fortran 77 using Thermath. Even though the final assembly of the code was doen manually, the largest portion of the program corresponds to automatically generated code. A program for the simulation of extraction columns was developed and showed excellent agreement with results available in the literature. The global phase stability program was tested in the identification of liquid-liquid phase transitions, showing results coherent with those from the extraction column program. Quadratic convergence rates in the Newton-Raphson method were obtained with both programs, as should be expected when the functions and their derivatives are correctly implemented. 相似文献
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EA Galati VL Nunes ME Dorval ET Oshiro G Cristaldo MA Espíndola HC da Rocha WB Garcia 《Canadian Metallurgical Quarterly》1996,30(2):115-128
Interleukin-1 beta (IL-1 beta) significantly inhibits insulin secretion from glucose stimulated islet cells. The mechanism for this inhibition has been hypothesized to be due to stimulation of the inducible form of nitric oxide synthase and a resulting increase in nitric oxide (NO) concentration. Ways to block the effect of IL-1 beta have focused on blocking the binding of IL-1 beta to the IL-1 receptor and the use of antioxidants to neutralize increases in NO. This report focuses on a 33 residue peptide synthesized based on the C-terminal region of the IL-1 beta molecule, a reported binding site of the IL-1 beta molecule, and the redoxcycling antioxidant pyrroloquinoline quinone (PQQ). The 33 residue peptide did not function as an antagonist, but as a weak agonist. High concentrations of PQQ itself inhibited glucose-dependent insulin release while low concentrations did not. PQQ had no effect on the actions of IL-1 beta. Three isosteric and isomeric analogues of PQQ were also investigated. One of the PQQ isomers had an inhibitory effect on insulin secretion at low concentrations where PQQ had no effect. These results reflect the sensitivity of islets to oxidative stress. 相似文献
10.
Antonio González‐Sarrías Juan A. Giménez‐Bastida María T. García‐Conesa María B. Gómez‐Sánchez Noelia V. García‐Talavera Angel Gil‐Izquierdo Carmen Sánchez‐Álvarez Luis O. Fontana‐Compiano Juan P. Morga‐Egea Francisco A. Pastor‐Quirante Francisco Martínez‐Díaz Francisco A. Tomás‐Barberán Juan Carlos Espín 《Molecular nutrition & food research》2010,54(3):311-322
Epidemiology supports the important role of nutrition in prostate cancer (PCa) prevention. Pomegranate juice (PJ) exerts protective effects against PCa, mainly attributed to PJ ellagitannins (ETs). Our aim was to assess whether ETs or their metabolites ellagic acid and urolithins reach the human prostate upon consumption of ET‐rich foods and to evaluate the effect on the expression of three proliferation biomarkers. Sixty‐three patients with BPH or PCa were divided into controls and consumers of walnuts (35 g walnuts/day) or pomegranate (200 mL PJ/day) for 3 days before surgery. Independently of the ETs source, the main metabolite detected was urolithin A glucuronide, (3,8‐dihydroxy‐6H‐dibenzo[b,d]pyran‐6‐one glucuronide) (up to 2 ng/g) together with the traces of urolithin B glucuronide, (3‐hydroxy‐6H‐dibenzo[b,d]pyran‐6‐one glucuronide) and dimethyl ellagic acid. The small number of prostates containing metabolites was likely caused by clearance of the compounds during the fasting. This was corroborated in a parallel rat study and thus the presence of higher quantities of metabolites at earlier time points cannot be discarded. No apparent changes in the expression of CDKN1A, MKi‐67 or c‐Myc were found after consumption of the walnuts or PJ. Our results suggest that urolithin glucuronides and dimethyl ellagic acid may be the molecules responsible for the beneficial effects of PJ against PCa. 相似文献