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71.
Sam C. Saunders 《技术计量学》2013,55(2):361-377
If the distribution of life length is a member of a specified subset of distributions which have increasing failure rates, we find a method of determining functions of the sample data which can be used to provide lower tolerance bounds of given confidence or a service life with specified assurance of no failures among a given number of items to be produced. The method of finding such functions of the observations is shown to be optimal in a sense and the calculation of a lower bound for the probability of no failure in the future production is carried out when such functions are used. The confidence in the tolerance bound and the assurance of no failure in a production lot of specified size are compared when using bounds obtained from these functions. 相似文献
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73.
In this study, carboxymethyl sago pulp (CMSP) derived from sago waste was successfully crosslinked with ferric ions in the presence of chitosan forming a novel immobilization matrix for p-nitrophenol (PNP)-acclimated activated sludge. On the basis of the shortest biodegradation time of PNP, the optimized operational conditions of immobilization were found to be: 7 w/v% CMSP, 9 g L−1 of activated sludge, 0.1 M ferric ion, and 15 min of crosslinking time. Observable inhibited PNP biodegradation was exhibited by the suspended activated sludge at the initial PNP concentration of 400 mg L−1. In contrast, complete mineralization was achieved by the CMSP/chitosan-immobilized activated sludge (CMSP/Ch-AS) beads. The results revealed the important role of CMSP/Ch hydrogel in protecting activated sludge from the toxicity of PNP. The CMSP/Ch-AS beads could be reused consecutively up to three and two cycles, respectively, for the biodegradation of PNP at 200 and 400 mg L−1, with the attainment of more than 99% of PNP removal at each cycle. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47531. 相似文献
74.
Nanoparticles have great potential as nanotherapeutics, delivery vectors, and molecular imaging agents due to their flexible properties. Although intracellular and nuclear delivery of nanoparticles is desirable for therapeutic applications, it remains a challenge. Cell penetrating peptides (CPPs) are a powerful tool for the intracellular delivery of various cargoes. Here it is reported that functionalization of nanoparticles with a myristoylated oligoarginine CPP promotes cellular uptake without increased toxicity. It is evident that the myristoylated CPP is much more effective in transporting nanoparticles than the unmodified CPPs. 相似文献
75.
This investigation presents an optimization of laminated cylindrical panels based on fundamental natural frequency. Also, trends of change in optimum stacking sequence while the proportions of structures vary, are studied which can be insightful for design purposes. A displacement based finite element model is used, in order to extract fundamental natural frequencies of T300/5208 Carbon/Epoxy cylindrical panels. To obtain optimum designs, the Globalized Bounded Nelder–Mead (GBNM) algorithm is employed. Predictions are compared with the results of Genetic Algorithm (GA) method and show faster and more accurate convergence to the global optimum, while variables are continuous in GBNM and discrete in GA. Moreover, verification of novel convergence criteria to ameliorate local searcher in GBNM is examined. 相似文献
76.
Sam Fletcher Mike J. S. Lowe Madis Ratassepp Colin Brett 《Journal of Nondestructive Evaluation》2012,31(1):56-64
The implementation of synthetic guided wave focusing to locate axially aligned defects in pipes has been investigated. Results
from both finite element computer models and experiments on real pipes are presented and the data show good agreement. Focusing
is necessary to improve the reflection coefficient from axially aligned defects, as the signals are very weak. The Common
Source Method (CSM) of synthetic focusing has been applied which makes it possible to apply focusing via post processing to
previously collected data. The dependence of reflection coefficient on crack length was measured for both through thickness
and part depth axially aligned defects, at a range of frequencies, using the torsional guided wave family. The results show
that the reflection coefficient is approximately doubled when focusing is employed, compared to the sensitivity for unfocused
fundamental torsional waves. However the sensitivity is still very low, so in practise this approach could only be used to
find severe defects. 相似文献
77.
78.
Sam van Haute Liesbeth Jacxsens Mieke Uyttendaele 《Critical reviews in food science and nutrition》2015,55(11):1529-1551
This paper comprises a selection tool for water disinfection methods for fresh produce pre- and postharvest practices. A variety of water disinfection technologies is available on the market and no single technology is the best choice for all applications. It can be difficult for end users to choose the technology that is best fit for a specific application. Therefore, the different technologies were characterized in order to identify criteria that influence the suitability of a technology for pre- or postharvest applications. Introduced criteria were divided into three principal components: (i) criteria related to the technology and which relate to the disinfection efficiency, (ii) attention points for the management and proper operation, and (iii) necessities in order to sustain the operation with respect to the environment. The selection criteria may help the end user of the water disinfection technology to obtain a systematic insight into all relevant aspects to be considered for preliminary decision making on which technologies should be put to feasibility testing for water disinfection in pre- and postharvest practices of the fresh produce chain. 相似文献
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