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101.
介绍了一种新的改进的烃回收(IHR)筛查方法:将大量的不同的储层通过IHR过程筛选;生成的初步的成分然后通过通用建模与仿真领域的代理。该方法是一种可以利用储层岩石/流体性质和技术经济的不同筛选标准快速筛选进而提高采收率的技术——定量的选择性的提高采收率。 相似文献
102.
Usefulness of a set of simple in vitro tests for the screening and identification of probiotic candidate strains for dairy use 总被引:1,自引:0,他引:1
Gabriel Vinderola Barbara Capellini Fernanda Villarreal Viviana Surez Andrea Quiberoni Jorge Reinheimer 《LWT》2008,41(9):1678-1688
A set of simple in vitro tests (identification by species-specific PCR, genetic diversity, phage sensitivity, growth and viability in milk, resistance to salts and flavor compounds, bacterial interactions, tolerance to simulated gastric juice and bile, bile salts deconjugation, hydrophobicity and β-galactosidase and antibacterial activities), that can be carried out in almost every laboratory of microbiology, mainly in developing countries where there is often limited access to sophisticated techniques, allowed us to identify, among 19 intestinal human isolates, a potential candidate for new probiotic dairy foods for the local market. Lactobacillus gasseri LgF37/1 performed well in the culture media used for the enumeration of probiotic bacteria in argentinian dairy products. This strain showed also high tolerance to the technological challenges assessed, bile salts resistance, the capacity to produce bacteriocin-like metabolites, to inhibit pathogenic bacteria, to deconjugate bile salts and high hydrophobicity. Further in vivo research should be carried out with this strain before claiming probiotic properties for it. However, the use of a set of simple in vitro techniques proved to be important to determine which strains should undergo future and more complex studies. 相似文献
103.
In the present work different energy reduction schemes (ERSs), used to reduce the consumption of steam for a multiple effect evaporator (MEE) system, are developed. These ERSs are condensate-, feed- and product-flashing and vapor bleeding. Further, a new scheme is proposed where condensate of vapor chest of an effect is used to preheat the liquor, which is entering into that effect using a counter current heat exchanger. This work also presents a comparative study between existing ERSs and selects the best ERS amongst these based on steam consumption as well as number of units involved. Further, in the present paper a simple graphical approach named “modified temperature path (MTP)” is developed for the analysis of different feed flow sequences of a MEE system to screen best possible feed flow sequence. To study the effect of different ERSs on steam consumption and MTP analysis an example of septuple effect flat falling film evaporator (SEFFFE) system, employed for concentrating weak black liquor in an Indian Kraft Paper Mill, is considered. The results show that ERSs reduce the steam consumption up to 24.6%. 相似文献
104.
随着裙带菜加工产量的增加,大量高盐加工尾水的排放对海洋环境造成了严重的污染。本研究以裙带菜盐渍加工尾水为培养基,根据化学需氧量(CODMn)去除率、甘露醇去除率以及生物量筛选出4株耐盐菌株。将这4株菌株分别应用于裙带菜盐渍加工尾水中,以CODMn去除率为主要指标测定72h生长曲线,优选出各菌株的最佳培养时间。最后将这4株菌株混合应用于裙带菜盐渍加工尾水。经鉴定4株菌株分别为:二尖梅奇酵母菌(Metschnikowia bicuspidata)、鞘氨醇菌(Sphingomonas)、胶红酵母菌(Rhodotorula mucilaginosa)、盐单胞菌(Cobetia)。各菌株对裙带菜加工尾水处理后CODMn去除率均在48h后达到最大值,去除率分别为84.90%,77.40%,79.20%,70.80%。4种混合菌株在28℃、150r/min摇床反应条件下的最佳接种量为3%,最佳培养时间为60h,CODMn去除率达到83.49%。 相似文献
105.
A new grade efficiency function T(x, α′, β) for the stationary screening process is presented. It is a function of particle size x, separation sharpness α′, and the newly introduced separation efficiency β. With this new grade efficiency, the screening classification process can be described exactly. Especially in the fine and coarse material range, a very good correlation with the measured values can be observed. A comparison of the grade efficiency function with separation sharpness α′, separation efficiency β and only with the measure for separation efficiency has shown that the new grade efficiency allows a significant improvement in the characterization of the stationary screen classification process. The new model of the grade efficiency function T(x, α′, β) shows a significant higher correlation with the measured values compared to other models, and is therefore very well suited to describe a grade efficiency for the stationary screening process. 相似文献
106.
凹山选矿厂通过进行中碎前安装圆振筛、一次磁选后加筛分作业、二次精选精矿用细筛把关、中矿再磨再选三项优化技术改造措施,使生产工艺流程基本适应原矿性质的变化,达到了生产能力、精矿品位、回收率三提高。 相似文献
107.
In examining the performance of screening scales, a distinction should be made between principal and additional diagnoses. The Psychiatric Diagnostic Screening Questionnaire (PDSQ) is a brief, psychometrically strong self-report scale designed to screen for the most common Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) Axis I disorders encountered in outpatient mental health settings. In the present report, the authors compared the performance of the PDSQ in identifying principal and comorbid disorders. Seven hundred ninety-nine psychiatric outpatients completed the PDSQ and were interviewed with the Structured Clinical Interview for DSM-IV. The sensitivity and negative predictive values of the PDSQ subscales were similar for principal and additional diagnoses. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
A. OHagan 《Reliability Engineering & System Safety》2006,91(10-11):1290-1300
The Bayesian approach to quantifying, analysing and reducing uncertainty in the application of complex process models is attracting increasing attention amongst users of such models. The range and power of the Bayesian methods is growing and there is already a sizeable literature on these methods. However, most of it is in specialist statistical journals. The purpose of this tutorial is to introduce the more general reader to the Bayesian approach. 相似文献
109.
This is a review paper. It describes the state-of-the-art of the research on reliability indicators for either electronic or mechanical components. Typical component failure patterns are presented and discussed. The concept of component screening using reliability indicators is then outlined. The paper sketches a theoretical approach to the problem of detecting flaws in components. The approach is based on an old concept of energy imbalance in flawed objects. 相似文献
110.
Bioprospecting in developing countries must be operated on a commercial scale as a biotechnology-based business that adds value to a natural resource, if it is to provide incomes to developing countries and their traditional peoples and incentives for the conservation of biodiversity resources. For example, the value of extracts of samples derived from plant or animal species may be increased by processing them into 96-well plates ready for high throughput screening. More advanced developing countries may wish to aquire their own screening capacity and thereby to participate directly in the process of new product discovery and to lay the basis for a local biotechnology industry. Either way, the developing country must normally enter into a commercial partnership with a company in an advanced country that can supply, in addition to the technology, the marketing know-how to guide screening efforts and the capacity to develop the market for the eventual new product and to manufacture and distribute it. A developing country that wishes a significant share in the intellectual property deriving from a successful development must be prepared to make a significant financial investment, to share the risk of failure and to delay the receipt of cash income. A developing country may seek quicker returns, with fewer risks and delays, by undertaking to develop new phytomedicines (herbal extracts sold directly for medicinal purposes), personal care products and nutriceuticals (food supplements). Alternatively, it may eschew the hope of large financial gains and devote itself to improving traditional medicines or finding cures for tropical diseases that affect poor people. 相似文献