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1.
Xiaoshuang Luo Xinxian Qin Zhengyi Liu Dan Chen Weiwei Yu Kankan Zhang Deyu Hu 《Biomedical chromatography : BMC》2020,34(1):e4694
A simple and rapid analytical method for the detection of trifloxystrobin, trifloxystrobin acid and tebuconazole in soil, brown rice, paddy plants and rice hulls was established and validated by liquid chromatography with tandem mass spectrometry. Acceptable linearity (R2 > 0.99), accuracy (average recoveries of 74.3–108.5%) and precision (intra- and inter-day relative standard deviations of 0.9–8.8%) were obtained using the developed determination approach. In the field trial, the half-lives of trifloxystrobin and tebuconazole in paddy plants were 5.7–8.3 days in three locations throughout China, and the terminal residue concentrations of trifloxystrobin and tebuconazole were <100 and 500 μg/kg (maximum residue limits set by China), respectively, at harvest, which indicated that, based on the recommended application procedure, trifloxystrobin and tebuconazole are safe for use on rice. The risk assessment results demonstrated that, owing to risk quotient values of both fungicides being <100%, the potential risk of trifloxystrobin and tebuconazole on rice was acceptable for Chinese consumers. These data could provide supporting information for the proper use and safety evaluation of trifloxystrobin and tebuconazole in rice. 相似文献
2.
属性区间识别理论模型研究及其应用 总被引:15,自引:3,他引:12
根据程乾生教授创立的属性识别理论模型[1] ,提出了属性测度区间的概念 ,建立了属性区间识别理论模型 ,并在自然科学学术期刊质量评价中进行了应用 . 相似文献
3.
物理实验课程考核、评估体系初探 总被引:4,自引:0,他引:4
对物理实验课程考核、评估方法进行了探讨,提出了物理实验课程考核、评估体系及实施细则.重点介绍了体系中的核心部分——正规的物理实验课程考试. 相似文献
4.
JOHN POPE 《Natural Resource Modeling》2003,16(4):439-464
ABSTRACT. The paper is an attempt to refute Quinn's ‘the Golden Age of fisheries population models has ended “hypothesis. The approach is to show it is possible to provide simple matrix based theory for use with delay difference equations applied to products of the 0th to 4th powers of length and numbers at length (Alias” proto‐moments“). It compares these to models just based upon numbers and biomass. It also shows examples (of comparatively little moment) indicating how using multiple proto‐moments could improve the ability of delay difference equations to handle the size dependent processes of maturity, selection, natural mortality rates and predation rates and thus improving the biological reality of these models. 相似文献
5.
Solveig Linko 《Accreditation and quality assurance》2002,7(2):55-59
Internal audits inherently effect quality improvement, and concrete results can be expected by careful planning. As audits
should improve the quality system in situ, the development of audits should not be neglected. ISO/IEC 17025 describes the
objectives of internal audits and management reviews in more detail compared to the former standards EN 45001 and ISO/IEC
Guide 25, although the main features are unchanged. This addresses continuous surveillance of the current practice. A brief
questionnaire on vertical audits was distributed to 74 of 120 employees at a Finnish private medical laboratory, Medix Laboratories
Ltd. A positive feed-back was received from the current management of audits. However, the study revealed that continuous
supervision of audits is needed. Many employees were not willing to perform audits if they had no previous experience. Additionally,
audits performed at the workbench were not considered as the best possible for fruitful discussions.
Received: 20 February 2001 Accepted: 30 November 2001 相似文献
6.
SUMMARY: In recent years, the multiparametric approach for evaluating perceptual rating of voice quality has been advocated. This study evaluates the accuracy of predicting perceived overall severity of voice quality with a minimal set of aerodynamic, voice range profile (phonetogram), and acoustic perturbation measures. One hundred and twelve dysphonic persons (93 women and 19 men) with laryngeal pathologies and 41 normal controls (35 women and six men) with normal voices participated in this study. Perceptual severity judgement was carried out by four listeners rating the G (overall grade) parameter of the GRBAS scale. The minimal set of instrumental measures was selected based on the ability of the measure to discriminate between dysphonic and normal voices, and to attain at least a moderate correlation with perceived overall severity. Results indicated that perceived overall severity was best described by maximum phonation time of sustained /a/, peak intraoral pressure of the consonant-vowel /pi/ strings production, voice range profile area, and acoustic jitter. Direct-entry discriminant function analysis revealed that these four voice measures in combination correctly predicted 67.3% of perceived overall severity levels. 相似文献
7.
Thomas P J Linsinger Alexander Bernreuther Philippe Corbisier Marta Dabrio Håkan Emteborg Andrea Held Andrée Lamberty Gaida Lapitajs Marina Ricci Gert Roebben Stefanie Trapmann Franz Ulberth Hendrik Emons 《Accreditation and quality assurance》2007,12(3-4):167-174
The potential approaches for third-party assessment of reference material producers are revisited and the activities of the
Reference Materials (RM) Unit of the Institute for Reference Materials and Measurements (IRMM) to obtain accreditation to
ISO Guide 34 and ISO 17025 are described. Accreditation was related to the Unit as all matrix RM activities of the institute
are concentrated there. A management system was established that allows sufficient flexibility to be applicable to a wide
range of RMs while being precise enough to ensure compliance with ISO Guides 30, 31 and especially 34 and 35. Accreditation
was achieved in 2004 with independent scopes for testing and RM production and was confirmed and extended in 2005. The key
aspects of the RM Unit's management system for RM production are presented.
Presented at BERM-10, April 2006, Charleston, SC, USA 相似文献
8.
Rashid A. Zeineh George Kyriakidis Roger Acey Christopher Smith 《Applied biochemistry and biotechnology》1986,13(2):119-125
Citrus tristeza virus (CTV) extracted from Etrog citron (C.medica L.) was immunoprecipitated. The immunoprecipitate was fractionated by SDS-PAGE and western blotted onto nitrocellulose. The CTV
antigens were determined by immunoblot analysis using rabbit anti-CTV IgG, and the protein-band pattern exhibited on the nitrocellulose
was assessed by soft-laser scanning densitometry. The densitometric tracing revealed the presence of bands that were not visible
to the naked eye. Using the superimposition mode of the instrument, it was also revealed that the protein-band patterns of
different CTV samples were not identical. Computer-aided soft-laser scanning densitometry proved to be a powerful approach
in the detection and assessment of protein bands revealed on nitrocellulose immunoblots, which we were previously unable to
do employing conventional methods. 相似文献
9.
为研究四川省重点河段水环境的安全性,利用综合评价指数法和模糊综合评价决策的数学模型对主要水系干流和支流河段的水质安全性做出了评价.结果显示,岷江流域的水质安全性较差,主要的污染物为重金属汞和铁,沱江和涪江流域的水质安全性较好. 相似文献
10.
Tamas Benko Agnes Szanyi Peter Mizsey Zsolt Fonyo 《Central European Journal of Chemistry》2006,4(1):92-110
The sustainable development and consumption need more efficient use of natural resources. As a consequence, the use of industrial
solvents demands their recovery instead of end-of-pipe treatment. It is not always clear, however, which treatment alternative
should be applied. Based on an industrial case study, the environmental and economic evaluation and comparison of the treatment
alternatives of a non-ideal solvent mixture containing azeotropes is investigated for determining the preferable option. For
the recovery of the industrial solvent mixture, two different separation alternatives are evaluated: a less effective alternative
and a novel design based on hybrid separation tools. An end-of-pipe treatment alternative, incineration, is also considered
and the split of the solvent mixtures between recovery and incineration is investigated. The environmental evaluation of the
alternatives is carried out using ‘Eco-indicator 99 life-cycle impact assessment methodology’. Economic investigation is also
accomplished. The economic features clearly favour the total recovery, however, the environmental evaluation detects that
if a recovery process of low efficiency is applied, its environmental burden can be similar or even higher than that of the
incineration. This motivates engineers to design more effective recovery processes and reconsider the evaluation of process
alternatives at environmental decision making. 相似文献