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91.
2,1,3‐Benzothiadiazole‐5,6‐Dicarboxylic Imide – A Versatile Building Block for Additive‐ and Annealing‐Free Processing of Organic Solar Cells with Efficiencies Exceeding 8%
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92.
A Thieno[3,2‐b][1]benzothiophene Isoindigo Building Block for Additive‐ and Annealing‐Free High‐Performance Polymer Solar Cells
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93.
Management of infrastructure projects is becoming increasingly challenging due to inherent uncertainties. The most effeective way to deal with uncertainty is to collect supplementary information and knowledge. When expensive or infeasible, quantification of uncertainty may be performed using analytical or simulation techniques. The City of Edmonton, Canada has approximately 4600 km of sewer pipes in the combined, sanitary, and storm sewer local systems with uncertainty issues related to deterioration. The City has taken a proactive approach with respect to sewer rehabilitation, as it is more cost-effeective to repair a defective pipe prior to failure rather than after a collapse. This article demonstrates an approach for predicting the condition of a sewer pipe and the related cost of rehabilitation, given the limited data. Three models are described in this article that are developed to assist the City of Edmonton to effeectively plan maintenance expenditure. Each model uses a combination of rule-based simulation and probability analysis to assist in the planning of future expenditures for sewer maintenance, thereby producing an invaluable planning tool. 相似文献
94.
Silicon - Silicon (Si) is very effective in the amelioration of heavy metal (HM) stress in different crop plants. This investigation was conducted to assess the protective role of Si in modulating... 相似文献
95.
Yasir Ul Haq Imran Murtaza Sadaf Mazhar Naeem Ahmad Awais A. Qarni Zeeshan Ul Haq Shahid A. Khan Mahmood Iqbal 《应用聚合物科学杂志》2020,137(40):49197
Electric power system applications demand for high-temperature dielectric materials. The improved performance of polymer nanocomposites requires improvement in their thermal conductivity & stability, dielectric stability and processing technique. However, they often lose their dielectric properties with a rise in temperature. Here, we offer a solution by incorporating electrically conducting material (MXene) and semiconducting inorganic nanoparticles (ZnO NPs) into an insulating PMMA polymer matrix to maintain high dielectric constant, both at the room and high temperature. Therefore, to achieve desirable thermal and dielectric properties is the main objective of the present study based on the homogeneous distribution of the nanofillers by in-situ bulk polymerization assisted by strong sonication in the corresponding polymer. The introduction of MXene and ZnO NPs into the PMMA not only acquires a substantial increment in the dielectric constant, to attain a value 437, with minimum energy loss of 0.36 at 25 Hz, but also improves the thermal conductivity of PMMA up to 14 times by causing the reduction of thermal resistance, which is actually responsible for the poor thermal conductivity of amorphous pure PMMA polymer. More importantly, hybrid PMMA/4:2 wt% MXene:ZnO nanocomposite leads to an excellent thermal stability. Moreover, further characterization of the synthesized nanocomposites by FTIR, SEM and XRD leads to the evaluation of strong interaction of ternary components with PMMA matrix. 相似文献
96.
<正>尽管在单壁碳纳米管(SWNTs)的合成和表征方面已经取得了重大进展,但还有一重大挑战,即寻找一条有效途径来接通纳米管及工程材料和结构之间的尺寸和性能的通道。为了将SWNT的超性能转化到中型和大型结构中,人们已经花费了很大精力来开发线性和平面SWNT组件。本文描述的静电 相似文献
97.
98.
During 2001-2005, 210 Salmonella enterica strains were isolated from seafood samples imported into US. Strains of S. enterica serovar Weltevreden were the most predominantly found among the 64 different serovars isolated. A total of 37 Salmonella Weltevreden isolates were characterized by pulsed-field gel electrophoresis (PFGE), plasmid profiles and antibiotic susceptibility to assess genetic diversity. Our results showed a low frequency of antibiotic resistance; 35 of the 37 isolates were sensitive to ampicillin, tetracycline, chloramphenicol, gentamicin, sulfisoxazole, streptomycin and kanamycin. Only two isolates, from samples originating in the Philippines and India, showed resistance to ampicillin and tetracycline and to streptomycin, sulfisoxazole and tetracycline, respectively. Of the 37 isolates, two isolates did not carry any plasmid and 35 isolates harbored several small and mega-plasmids. These isolates were differentiated into 10 distinct types based on plasmid profiles. Four different PFGE clusters were obtained with a genetic similarity of 66-76%. Four groups of isolates (formed by two or three isolates each) showed 100% similarity in the PFGE profiles. One of these groups included strains isolated in Vietnam in 2003, 2004 and 2005 from fish and shrimp. The other groups included strains isolated in Vietnam, Indonesia and Thailand in 2000, 2004 and 2005 from snail, shrimp and fish. Our findings show genetic diversity and temporal persistence of S. enterica serovar Weltevreden in recently monitored seafood imports. 相似文献
99.
Microbiological survey of tofu sold in a rural Illinois county. 总被引:1,自引:0,他引:1
The purpose of this study was to determine the microbial status of tofu sold in a rural Illinois county and assess the factors contributing to the safety of tofu. Six brands of tofu from eight different stores (60 total samples) were purchased and analyzed for temperature, pH, total aerobic bacteria, and the presence of coliforms. Relationships between age, temperature, pH of tofu, and total aerobic bacteria were tested. An analysis of variance was also performed to test for differences in total bacterial counts among the brands. Mean aerobic bacterial counts ranged from 0 to 7.76 x 10(7) CFU/g. Fifty-five percent of the tofu tested fell within the excellent range for freshness as delineated by the standards developed by the Soyfoods Association of North America, 6.7% fell within the acceptable range, 6.7% within the marginal range, and 28% within the unacceptable range. Sixteen percent of the samples contained coliform bacteria. No significant correlation was found between variables, except pH with total aerobic bacterial counts (r = -0.51) and pH with eosin-methylene blue agar counts (r = -0.67). Most of the tofu was displayed at unsafe temperatures (>5 degrees C) for potentially hazardous foods. This study confirmed the concerns regarding safety of tofu sold in the grocery stores. Based on these results, special training on tofu storage and handling is recommended for grocery stores selling this food product. 相似文献
100.
Andro Mondala Rafael Hernandez William Holmes Todd French Linda McFarland Darrell Sparks Monica Haque 《American Institute of Chemical Engineers》2013,59(11):4036-4044
The co‐fermentation of glucose and xylose by activated sludge microorganisms for the production of microbial oils for use as biodiesel feedstock was investigated. Various carbon sources at initial concentration of 60 g/L and C:N ratio 70:1 were investigated: xylose, glucose, and 2:1 and 1:2 (by mass) glucose/xylose mixtures. Oil accumulation ranged between 12 to 22% CDW, the highest of which was obtained when xylose was the sole substrate used. Kinetic modeling of the fermentation data showed that specific growth and oil accumulation rates were similar in all substrate types and the lipid coefficient ranged from 0.02 to 0.06 g/g of sugar consumed. The fatty acid methyl ester yield and composition of the lipids showed their suitability for conversion to biodiesel. Based on the results, lignocellulose sugars could be used as fermentation substrates by activated sludge microorganisms for enhancing the oil content of sewage sludge for its use as a sustainable biofuel feedstock source. © 2013 American Institute of Chemical Engineers AIChE J, 59: 4036–4044, 2013 相似文献