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排序方式: 共有625条查询结果,搜索用时 15 毫秒
61.
Novel Brönsted acid functionalized magnetic polymeric nanocomposite, Ba0.5Sr0.5Fe12O19@PU-SO3H, has been successfully synthesized and characterized by field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), Fourier transform infrared spectroscopy (FT-IR), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM) and thermogravimetric analysis (TGA) techniques. The catalytic activity of the nanocomposite was tested in the regioselective synthesis of 7-aryl-benzo[h]tetrazolo [5,1-b] quinazoline-5,6-diones in an eco-friendly and recyclable media, deep eutectic solvent (DES), based on choline chloride and urea. This novel method offers several advantages, such as high yields, short reaction time, environmentally friendly reaction media, easy isolation of the product, and also offers an easy method for the synthesis of nanocatalysts. The catalyst was readily recycled by the use of an external magnetic field and could be reused 6 times without significant loss of activity or mass. DES as one of the most promising environmentally benign and cost-effective alternatives to conventional ionic liquids and volatile organic solvents was recovered from the aqueous filtrate by evaporating the water under vacuum. The recycled DES was used up to 4 runs without any loss in activity. 相似文献
62.
A multiagent framework for coordinated parallel problem solving 总被引:1,自引:1,他引:0
Today’s organizations, under increasing pressure on the effectiveness and the increasing need for dealing with complex tasks beyond a single individual’s capabilities, need technological support in managing complex tasks that involve highly distributed and heterogeneous information sources and several actors. This paper describes CoPSF, a multiagent system middle-ware that simplifies the development of coordinated problem solving applications while ensuring standard compliance through a set of system services and agents. CoPSF hosts and serves multiple concurrent teams of problem solving contributing both to the limitation of communication overheads and to the reduction of redundant work across teams and organizations. The framework employs (i) an interleaved task decomposition and allocation approach, (ii) a mechanism for coordination of agents’ work, and (iii) a mechanism that enables synergy between parallel teams. 相似文献
63.
Planning theory is increasingly concerned with how urban planning is engaged in the management of cultural difference and diversity. But there is a need to consider the conditions by which difference is ‘allowed’ in processes of planning and urban development. This paper explores the conditions under which the Roma is admitted into the image of Jungbusch, Mannheim, as a ‘diverse’ neighbourhood, and thereby into the category of diversity in the local discourse of planning. We argue that cultural differences are allowed in the category of diversity to the degree that they contribute to the economic and normative aims of managed diversity. 相似文献
64.
Lara Valentín Beata Kluczek‐Turpeinen Pekka Oivanen Annele Hatakka Kari Steffen Marja Tuomela 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(6):851-858
BACKGROUND: For most dioxin‐contaminated sawmill soils, combustion is recommended. However, the process may be inefficient if the soil has a high organic matter content. The use of saprotrophic basidiomycetous fungi is an alternative for pretreatment of this kind of soil. A total of 147 fungi were evaluated for their ability to grow in sawmill soil. From this screening, the best soil colonizing fungi were selected to study their enzyme activities and degradation of soil organic matter. Pine (Pinus sylvestris) bark was used as a co‐substrate to propagate the fungi into the soil. The activities of manganese peroxidase (MnP), laccase, endo‐1,4‐β‐glucanase, endo‐1,4‐β‐xylanase, and endo‐1,4‐β‐mannanase were analysed from the inocula and fungal treated soil. RESULTS: The screening revealed that 56 out of 147 fungi were able to grow in non‐sterile soil, and most of them were litter‐decomposing fungi (LDF). In pine bark cultures, the highest enzyme activities were observed with Phanerochaete velutina, which produced 5 U g?1 of MnP. The activity of endo‐1,4‐β‐glucanase was generally higher than that of other hydrolytic enzymes. The highest carbon loss from soil with a high organic matter content was achieved by P. velutina (3.4%) and Stropharia rugosoannulata (2.4%). CONCLUSIONS: Many LDF, and in addition the white‐rot fungus P. velutina, are potential degraders of soil organic matter since they showed good growth and respiratory activity. Pine bark was a suitable lignocellulosic co‐substrate and a good promoter of MnP activity. Copyright © 2009 Society of Chemical Industry 相似文献
65.
The Federal Rules of Evidence prohibit disclosure to civil jurors of information that is arguably related to their decision-making (e.g., that either party is insured). The basis for so-called "blindfolding" is that a jury might be biased by this information to alter its appraisal of the evidence to reach a desired verdict. The purpose of this study was to examine the extent to which mock juries in an automobile negligence case discuss several "silent factors" during deliberation (viz., insurance carried by the parties, the payment of attorneys' fees, and previous settlements between the plaintiff and other defendants) and the effects of such discussion on their compensatory damage award. We presented summaries of the evidence that varied in the severity of the plaintiff's injuries and the reprehensibility of the defendant's conduct. These variables influenced judgments of liability and damage awards. Analysis of the content of jury deliberations regarding damages showed that, although nearly all juries talked about silent factors, the size of their damage awards was unrelated to the frequency of these discussions and that such discussion accounted for only a very small portion of the variance in awards. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
66.
An experimental study of an alkaline fuel cell test plant with a 0.5 kW fuel cell module is presented in this paper. The characteristics of the fuel cell module are measured in different steady state load conditions and with different electrolyte temperatures. The results are analysed by calculating the different efficiencies of the module. 相似文献
67.
冲击干燥提高效率和产能 总被引:1,自引:0,他引:1
Kari Juppi Petri Norri 《中华纸业》2008,(22)
对美卓造纸机械的冲击干燥装置进行了简述。将冲击干燥与传统干燥的蒸发效率进行了比较,对比结果表明了冲击干燥装置的优越性。 相似文献
68.
Koskinen MT Wellenberg GJ Sampimon OC Holopainen J Rothkamp A Salmikivi L van Haeringen WA Lam TJ Pyörälä S 《Journal of dairy science》2010,93(12):5707-5715
Fast and reliable identification of the microorganisms causing mastitis is important for management of the disease and for targeting antimicrobial treatment. Methods based on PCR are being used increasingly in mastitis diagnostics. Comprehensive field comparisons of PCR and traditional milk bacteriology have not been available. The results of a PCR kit capable of detecting 11 important etiological agents of mastitis directly from milk in 4h were compared with those of conventional bacterial culture (48h). In total, 1,000 quarter milk samples were taken from cows with clinical or subclinical mastitis, or from clinically healthy quarters with low somatic cell count (SCC). Bacterial culture identified udder pathogens in 600/780 (77%) of the clinical samples, whereas PCR identified bacteria in 691/780 (89%) of the clinical samples. The PCR analysis detected major pathogens in a large number of clinical samples that were negative for the species in culture. These included 53 samples positive for Staphylococcus aureus by PCR, but negative by culture. A total of 137 samples from clinical mastitis, 5 samples from subclinical mastitis, and 1 sample from a healthy quarter were positive for 3 or more bacterial species in PCR, whereas culture identified 3 or more species in 60 samples from clinical mastitis. Culture identified a species not targeted by the PCR test in 44 samples from clinical mastitis and in 9 samples from subclinical mastitis. Low SCC samples provided a small number of positive results both in culture (4/93; 4.3%) and by PCR (7/93; 7.5%). In conclusion, the PCR kit provided several benefits over conventional culture, including speed, automated interpretation of results, and increased sensitivity. This kit holds much promise as a tool to complement traditional methods in identification of pathogens. In conventional mastitis bacteriology, a sample with 3 or more species is considered contaminated, and resampling of the cow is recommended. Further study is required to investigate how high sensitivity of PCR and its quantitative features can be applied to improve separation of relevant udder pathogens from likely contaminants in samples where multiple species are detected. Furthermore, increasing the number of species targeted by the PCR test would be advantageous. 相似文献
69.
70.
A. Nevalainen P. Partanen E. Jskelinen A. Hyvrinen O. Koskinen T. Meklin M. Vahteristo J. Koivisto T. Husman 《Indoor air》1998,8(Z4):45-49
Abstract A random sample of 450 houses representing various decades was surveyed by trained civil engineers for signs of water leaks or condensation. In 80% of the houses, signs of current or previous moisture fault were observed. In most houses, the surveyors made at least two separate observations of moisture but the occupants missed one in every two of these signs of moisture damage. Part of the faults were caused by flaws in design or construction, and part were due to aging of materials. Approximately 55% of the Finnish houses (i.e., a total of nearly 500 000 houses), were assessed to be in need of repair or more thorough inspection. The observations were equally frequent in the houses of different age, but certain types of moisture damage were characteristic of certain types of buildings or constructional methods used in different eras. Roof geometry was a significant factor accounting for roof leakages. The majority of the faults could be repaired at reasonable cost. 相似文献