The photodegradation of metronidazole in the presence of coexisting pharmaceuticals

The objective of this study was to investigate if coexisting compounds could affect the fate of pharmaceuticals in surface water under solar irradiation. The degradation of metronidazole (MET) in the presence of different coexisting pharmaceuticals was investigated in batch experiments with exposure to sunlight. Tinidazole, which has a similar structure to MET, was employed as an analogue. The results indicated that the presence of an analogue with a similar photosensitive group to MET could inhibit the photodegradation of MET. In addition, the effect of coexisting pharmaceuticals with different absorption spectra on the degradation of MET was investigated. The results showed that the effect depended on the degree of overlapping absorption spectra between MET and the coexisting pharmaceuticals. The relationship between the degree of the influence and the ultraviolet absorption spectra of coexisting pharmaceuticals found in this study could give guidance in assessing the fate of pharmaceuticals in environmental water.     

库什塔依水电站工程建设质量管理

库什塔依水电站工程面临着工期紧、任务重、沥青混凝土冬季施工等问题,给现场的施工管理带来了挑战。在建设过程中严格执行中电投新疆公司管理制度,通过建立健全质量保证体系,完善质量保证措施,强化参建各方的质量责任意识,加强过程监控,实现了工程建设的质量目标。     

Biochemical responses of the copepod Centropages tenuiremis to CO(2)-driven acidified seawater

An ecophysiological experiment was conducted to examine the biochemical effects of acidified seawater containing elevated concentration of CO(2) (C(CO2) 0.08, 0.20, 0.50 and 1.00%) on the copepod Centropages tenuiremis. AchE, ATPase, SOD, GPx, GST, GSH level and GSH/GSSG ratio of the copepod were analyzed. The results showed that elevated C(CO2) and the duration of culture time significantly influenced several biochemical indices in C. tenuiremis (ATPase, GPx, GST, GSH and SOD). Furthermore, the principal component analysis results indicated that 72.32% of the overall variance was explained by the first three principal components (GPx, SOD and GSH). Changes in GPx and GSH levels may play a significant role in the antioxidant defense of copepods against seawater acidification. The long-term response of copepods to seawater acidification and the synergistic effects of acidification with other environmental factors, such as temperature, salinity and trace metal need further investigation.     

中国西南易旱地区识别的探讨

利用中国西南地区13个气象站56年以上的长系列月降雨量资料,统计分析了降雨的多年变化、季节变化特征,以及连续少雨时间段事件,探讨了易旱区识别的定性定量分析方法,初步建立了气象易旱区识别指标及标准,将5个地区识别为易旱地区,5个地区识别为较易旱地区,3个地区识别为不易旱地区,将6个地区识别为易发长时间干旱地区,并对识别方法进行了讨论,为进一步的易旱区综合识别研究提出了建议。     

唐山市工业用水效率分析与控制

从万元工业取水量、用水重复利用率和万元工业取水量累积下降百分比3个方面,对唐山市近年来工业用水效率变化情况进行了分析计算,根据分析结果和唐山市工业用水存在问题,提出了坚持产业结构调整、提高用水技术、增加非常规水利用率等提高工业用水效率的控制方法及措施.     

对中央部门机关政府采购开展绩效评价的几点思考

中央部门机关政府采购绩效评价,应该以党和国家关于缋效管理和政府采购的一系列重要文件为指导,针对政府采购工作全过程,以绩效目标为牵引,以绩效指标和评价标准为重点,以完善的评价组织方法为推动力,贴近实际、注重实效,按照事前、事中、事后三个阶段,客观评定中央部门机关政府采购工作投入产出比,以及工作的效益和效率情况,为政府采购工作的开展提供借鉴.     

How Often to Sample a Continuous-Time Process in the Presence of Market Microstructure Noise

In theory, the sum of squares of log returns sampled at highfrequency estimates their variance. When market microstructurenoise is present but unaccounted for, however, we show thatthe optimal sampling frequency is finite and derives its closed-formexpression. But even with optimal sampling, using say 5-minreturns when transactions are recorded every second, a vastamount of data is discarded, in contradiction to basic statisticalprinciples. We demonstrate that modeling the noise and usingall the data is a better solution, even if one misspecifiesthe noise distribution. So the answer is: sample as often aspossible.     

美国稳定价值基金探讨

稳定价值基金（Stable Value Fund）通过保证本金和累计利息达到避免净值波动和收益稳定的投资目标，实现货币市场基金高流动性和债券基金更高收益的最佳组合，为投资者提供稳定的投资价值。本文介绍了美国稳定价值基金的发展概况，分析了其运作机制、核心优势及其发展的历史原因，并对稳定价值基金与保本基金做了比较。     

明明白白话治理

治理(governance)已成为现代经济社会的一句口头禅。譬如会计师事务所治理,就是指一整套符合执业机构发展规律的权利安排、责任分工和约束机制。检视整个事务所治理链条,缺少合格的合伙人或领导人队伍无疑是其中最薄弱的一环。我国目前的合伙人构成大约有四种类型:——学者型。这类合伙人原来的身份主要为大学学者、机关企事业单位从事财会、审计工作的高管人员。他们通常具有较高的学历,有较深的理论功底,对新事物的脉动较为敏感。——商人型。这类合伙人只在乎“孔方兄”,名曰一切为了收费。什么“专业形象”,什么“职业操守”,什么“公众…     

审计期望差产生的经济学分析

本文运用经济学的供给和需求分析框架,结合信息经济学理论分析了审计需求和审计供给,剖析了两类审计期望差的成因,认为合理的期望差源于给定审计需求下的审计供给不足,而不合理的期望差源于信息不对称条件下的审计需求过度,提出审计理论上应提倡社会调查等实证研究方法,实务上应改进审计报告的披露内容,以期缩小审计期望差。