阿莫西林克拉维酸钾片含量测定方法的改进

为解决实际应用中克拉维酸钾峰与后相邻杂质的分离度达不到要求的问题,建立了一种同时测定阿莫西林克拉维酸钾片中阿莫西林和克拉维酸钾含量的新方法,采用反相高效液相色谱法(RP-HPLC),Ultimate AQ-C_(18)色谱柱(4.6mm×250 mm,5μm),以pH值为4.4的0.05 mol/L磷酸二氢钠缓冲液为流动相,柱温为35℃,流速为1.0mL/min,检测波长为220nm。结果表明:阿莫西林和克拉维酸钾两主峰与相邻杂质得到完全基线分离,分离度大于1.5;克拉维酸钾对照品溶液质量浓度为0.050 0~0.500 1mg/mL时与峰面积的线性关系良好(r=0.999 8),平均回收率(n=9)为100.14%,RSD值为0.24%;阿莫西林对照品溶液质量浓度为0.100 0~1.000 1mg/mL时与峰面积的线性关系良好(r=0.999 9),平均回收率(n=9)为100.45%,RSD值为0.17%。与原有的《中华人民共和国药典》方法相比,新的阿莫西林克拉维酸钾片含量测定方法专属性好,准确度高,操作简便快捷,结果可靠,可作为一种质量控制方法。     

The impact of purchasing strategy-structure (mis)fit on purchasing cost and innovation performance

The organizational design literature strongly supports the notion of “structure follows strategy”, and suggests that a misfit between the two has a negative effect on performance. Building on this line of argument, we examine to what extent the (mis)fit between purchasing strategy and purchasing structure impacts purchasing performance. We focus on cost and innovation purchase category strategies, and examine how the deviation from an ideal purchasing structure defined along three dimensions (centralization, formalization, and cross-functionality) impacts purchasing performance. Analysing data collected from 469 firms in ten countries, we demonstrate that a strategy-structure misfit negatively impacts purchasing performance in both cost and innovation strategies. We also find that purchasing proficiency is a mediator in this relationship between misfit and performance. Our findings aid managerial decision making by empirically validating the necessity of having the right purchasing structure for successfully executing different purchasing strategies.     

The ‘Blogosphere’ as a platform for interpretative phenomenological analysis: the case of TEFL tourism

The use of the Internet is becoming increasingly integral to the day-to-day operations of society, facilitating an interconnected and globalised world, where geographic barriers are no longer a defining criteria for communication. This opens the researcher up to a realm of research opportunities, which to-date have been under-exploited. This paper contributes to the wider body of literature addressing the concept of Online research, demonstrating in practice how it can be utilised in the context of interpretative phenomenological analysis. It is argued that netnography is akin to interpretative phenomenological analysis (IPA) in that it accounts for an individual’s personal perception or account of an event or state, as opposed to attempting to produce an objective record. This paper outlines how blog analysis can be utilised in the context of IPA, demonstrating how this worked in practice during the initial exploratory research phase of the teaching English as a foreign language tourism phenomenon.     

Three decades of productivity change in French beef production: a Färe‐Primont index decomposition

The Färe‐Primont index is used to evaluate total factor productivity (TFP) change and its components for a sample of French suckler cow farms in grassland areas in 1985–2014. The results reveal an increase in TFP of 6.6 per cent over the whole observation period, with technological progress being the major source of productivity growth. Meanwhile, efficiency decreased. Farms experienced great technological progress from 1991 to 2000. From a methodological point of view, the comparison with results obtained with Malmquist indexes shows similar trends but different magnitudes, with the Malmquist index overestimating the TFP and technological changes compared to the Färe‐Primont index. In addition, the use of a sequential approach that restricts technological change to being positive or null allows for the precise calculation of technology changes, disregarding the effects of external conditions that are captured in efficiency changes. Finally, the estimation of full dimensional efficient facets (FDEFs) that guarantees the positivity of all shadow prices used to assess the mix efficiency component of TFP change is promising.     

Consumer Preferences for Fresh Tomatoes in Benin using a Conjoint Analysis

Constraints related to the technical and socioeconomic aspects of adopting tomato varieties are well documented. However, preferences relating to the demand for this fruit are rarely studied. In fact, demand for the different varieties of tomatoes might be related to consumers’ preferences for the extrinsic (color, size) and intrinsic (taste, nutritive value, water content) characteristics specific to each variety. It is therefore indispensable to determine the characteristics of tomatoes preferred by consumers. We examine consumers’ preferences for tomato attributes among a sample of 600 consumers in four representative markets in the main cities in southern Benin. The study also identifies potential segments of consumers and the market shares of each profile for each segment. The study identifies four potential tomato market segments, two of which have a strong preference for local tomatoes, namely, those that can be conserved for long periods and those with a firm consistency.     

Measuring industrial upgrading: applying factor analysis in a global value chain framework

ABSTRACT

A key question for promoting international competition is how to improve the position of countries and industries in global value chains (GVCs). The first step is to properly measure industrial upgrading in GVCs. This is not a trivial issue because upgrading has not been defined unambiguously. Several authors have used different (and sometimes related) measures, all of which indicate certain aspects of upgrading. Rather than trying to find the single, ultimate measure of upgrading, we propose a different approach. We examine the multidimensionality of industrial upgrading, using eight indicators in factor analysis. Four of the eight indicators adopt the GVC perspective and include, for example, the growth of the share in value-added exports. We provide three quantitative dimensions of industrial upgrading: process upgrading, product upgrading, and skill upgrading. With these dimensions, we compare and analyze the upgrading of different countries and industries using the World Input–Output Database.     

Structural production layer decomposition: a new method to measure differences between MRIO databases for footprint assessments

Recent empirical assessments revealed that footprint indicators calculated with various multi-regional input–output (MRIO) databases deliver deviating results. In this paper, we propose a new method, called structural production layer decomposition (SPLD), which complements existing structural decomposition approaches. SPLD enables differentiating between effects stemming from specific parts in the technology matrix, e.g. trade blocks vs. domestic blocks, while still allowing to link the various effects to the total region footprint. Using the carbon footprint of the EU-28 in 2011 as an example, we analyse the differences between EXIOBASE, Eora, GTAP and WIOD. Identical environmental data are used across all MRIO databases. In all model comparisons, variations in domestic blocks have a more significant impact on the carbon footprint than variations in trade blocks. The results provide a wealth of information for MRIO developers and are relevant for policy makers designing climate policy measures targeted to specific stages along product supply chains.     

基于循环经济的绍兴休闲观光农业发展研究

［目的］休闲观光农业建设是绍兴市产业转型升级的关键一步，探寻休闲观光农业新模式，能够为休闲农业发展提供理论参考。［方法］文章采用变异系数法确定指标权重，多因素综合分析法测算观光农业发展水平，从循环经济角度出发，评价2001—2016年绍兴市休闲观光农业发展可持续性，提出发展中存在的问题并探索循环型的休闲观光农业新模式。［结果］（1）2001—2016年以来，经济发展可持续性得分较高，资源环境可持续得分次之，循环经济可持续发展偏低。（2）现阶段绍兴市休闲观光农业发展主要存在休闲观光农业自然环境不断遭到破坏，休闲观光农业缺乏整体规划，休闲观光农业旅游支撑体系不够健全等问题。（3）未来发展中，循环经济发展下的休闲观光农业可以开发建设时空复合循环型、资源综合利用循环型、能量多级利用循环型、综合开发利用循环型等4种模式。［结论］未来绍兴市应将循环经济的理念融入到休闲观光农业中，因地制宜，科学选择循环型休闲观光农业发展模式； 规划先行，科学利用农业旅游资源； 强化保障，建立休闲观光农业支撑体系，全面推动休闲观光农业健康持续发展。     

The Urban–Rural Gap of Chinese Household Finance

Using data from a large household survey, we investigate the size of China’s urban–rural gap in ownership of bank deposits, risky financial assets, and credit cards. We further examine the factors underlying the gap using decomposition analysis. Compared to their urban counterparts, rural Chinese are much less likely to own a variety of financial products. Both demand-side barriers and supply-side barriers to financial inclusion exist in China. More, we use instrumental variable analysis to address the endogeneity of the local supply of financial service. Above all, our study indicates that a large financial services vacuum in rural areas needs to be filled.     

福鼎市桐江溪卤乙酸分布特征及潮汐影响分析

为了掌握福鼎市桐江溪卤乙酸(HAAs)的含量、时空分布规律及其来源,对水体中HAAs化合物进行取样调查。根据桐江溪水文情势及沿岸特点设置10个取样点,于2017年12月及2018年7月按照涨潮、退潮情况分别对水样进行采集,检测HAAs分布情况,同时将卤乙酸(HAAs)与水质特性、涨退潮进行了相关性分析。研究发现,HAAs是普遍存在于桐江溪中的污染物质。其中,一氯乙酸(MCAA)、二氯乙酸(DCAA)、三氯乙酸(TCAA)、一溴乙酸(MBAA)、二溴乙酸(DBAA)等5种卤乙酸(HAA_5)质量浓度为0.44～3.39μg/L;一氯乙酸(MCAA)、二氯乙酸(DCAA)、三氯乙酸(TCAA)、一溴乙酸(MBAA)、二溴乙酸(DBAA)、三溴乙酸(TBAA)、一溴一氯乙酸(BCAA)、一溴二氯乙酸(BDCAA)、二溴一氯乙酸(CBDAA)等9种卤乙酸(HAA_9)质量浓度为0.83～56.15μg/L。桐江溪中HAAs主要为DCAA,TCAA,TBAA 3种,其中DCAA为制药厂及医院排水导致,主要分布在下游;TCAA主要来源于河段上游的农业生产活动;TBAA为上游沸石矿尾矿库受雨水冲刷而流入的Br~-所生成,主要分布于河流中下段。相关性分析结果表明,温度与HAA_5,HAA_9质量浓度呈现正相关,pH值与HAA_5,HAA_9质量浓度呈现负相关;TCAA质量浓度于相同季节不同潮汐及不同季节相同潮汐时均呈现上游高于下游的现象,其他HAAs均不因涨潮、退潮的差异造成质量浓度分布的变化。掌握桐江溪HAAs的含量、时空分布规律及来源,探讨其与水质的相关性,对于净水工艺选择、水厂出水HAAs含量的溯源分析、水体环境风险评估以及研究水生生物体内HAAs的累积效应等有重要意义。