安昌河绵阳段水体中TOC、COD_(Cr)、BOD_5、DO的相关关系研究

本文选取安昌河绵阳段6个断面,研究其水体中总有机碳(TOC)、化学需氧量(CODCr)、生化需氧量(BOD5)和溶解氧(DO)之间的内在联系与相关性.结果表明TOC与CODCr、BOD呈线性相关性,其中CODCr=2.406TOC-34.186,r=0.78,在BOD5和TOC相关性分析中,将各采样点的BOD5和TOC值进行一元线性回归可得出0.786BOD5和TOC之间存在显著的线性相关性;CODCr与BOD5之间同样存在着线性相关性,但相关性不显著;DO和TOC、CODCr、BOD5之间存在着负相关关系.通过对四个指标的相关性分析,建立各指标之间的相互关系模型来探讨不同指标间替代的可能性.本研究结果对环保部门进行污染治理和环境管理的科学决策具有重要意义.     

用溶氧仪测定水样BOD5的方法

废水、工业废水、地表废水的BOD是用来描述水中有机物进行生物化学过程消耗的溶解氧的程度。在污水处理厂和地表水处理系统中，测量BOD是一种重要的分析手段，用来检测处理程度的好坏。该文介绍采用氧电极法对葡萄糖溶液、谷氨酸溶液的BOD，进行测定，并与5天培养法（GB7488--87）相比，可简化操作，不消耗药品，准确度较高，适用于大批试样的同时测定和教学需要。     

污水样微核率与COD值和BOD值的关系

利用蚕豆根尖细胞微核试验检测湛河水体中是否存在致突变因子污染,方法准确可靠,但工作量较大。针对固定的监测水体,利用微核率与COD值和BOD值的相关性,建立回归方程,便可用水样的COD值或BOD值来估计其微核率。沿湛河采集18个样点的污水作为水样测定其微核千分率（MCN‰）、COD值和BOD值,分析表明,CODMn和BOD与微核千分率的相关系数（r）分别为0．91和0．93,均存在极显著的相关关系,由此分别建立其回归方程为Y=0．0737XCOD＋3．2853,Y=0．161XBOD＋5．9622。     

BOD5与DO相关分析的探讨

通过分析得知,本地区生活污水及水温大于10℃的地面水,其BOD5与DO呈显著负相关。回归方程分别为BOD5=21．54—2DO,BOD5=8．83—0．65DO。这样,已知DO可估算出BOD5,再由BOD5计算公式求出水样在稀释水中所占的比例。多年来对各种生活污水和水温大于10℃的地面水的测试验证,表明此方法简便易行。     

生化需氧量在污水检测中的应用研究

近年来,城市化发展日益迅速、工业化进程推进加快,水污染越来越严重,水环境保护的压力日益加大,城市污水检测、处理水平已成为一个城市文明程度的重要标志,成为制约城市可持续发展的重要因素。文章就如何运用生化需氧量检测污水做相关探讨,希望能为污水处理探索一条便捷之路。     

五日生化需氧量(BOD5)测定中接种液的几种获取方法

在对抚仙湖入湖河流BOD5进行分析的过程中,对几种接种液的来源、配比、预处理及接种稀释水的配制方法进行了研究,并通过一系列的实验数据说明了这些配制方法的可行性.     

BOD5测定中硝化作用的干扰和消除

探讨生物处理净化出水的BOD5测定了硝化作用产生的干扰问题，验证氨氮硝化的耗氧量对BOD5测定结果的影响，为得到BOD5的准确结果，可以在生物处理净化后的水样中加入ATU，消除干扰。     

CASS工艺处理油漆生产废水

采用隔油——气浮——CASS——过滤工艺处理高浓度油漆生产废水，工程运行稳定，出水水质达到国家一级排放标准。     

Body composition in athletes: A comparison of densitometric methods and tracking of individual differences

Abstract

Measuring body composition in athletes can provide valuable information on training and nutritional status. The aim of this study was to compare percentage body fat (PF) obtained by hydrostatic weighing (HW) to PF via air-displacement plethysmography (ADP), and to evaluate tracking of individual differences between both methods over time in elite college athletes. Thirty-one male and 33 female athletes (18.0–36.4 years) were measured by ADP and HW. Twenty-one subjects (10 men, 11 women) were measured again 61±11 days later to evaluate consistency of individual differences between methods. Mean PF differed significantly in men (HW: 9.4±2.4%, ADP: 11.3±3.4%, P<0.05) but not in women (HW: 19.1±2.4%, ADP: 19.5±3.7%). A significant trend in mean bias was found in both genders between HW-ADP suggesting an underestimation of PF by ADP at lower mean PF and an overestimation of PF by ADP at higher mean PF. Up to 73% of variance in differences between methods at follow-up was explained by differences between methods at the first measurement occasion. Both densitometric methods cannot be used interchangeably when measuring and tracking the body composition of individual elite athletes using a 2-component model of body composition. Differences between methods appear to track within an individual. The individual-specific causes of these differences remain to be determined.