精确曝气系统在污水厂中应用

精确曝气系统旨在通过污水厂区进水参数数据来精确控制生物池的溶解氧DO值,即合理控制曝气量,实现自动对风机风量的控制,对风机的能源损耗有一定降低。     

浑河(抚顺市区段)溶解氧的分布特征分析

本文以浑河(抚顺市区段)2011―2014年溶解氧分布情况为对象,并对其分布特征进行了分析和探讨。结果表明:溶解氧空间分布上有沿程降低的趋势;时间分布上,2012―2014年溶解氧均值相比2011年均有升高,其中2012年溶解氧均值含量最高,年内变化具有显著的季节性特征,上游溶解氧含量变化呈"凹"型,夏季7、8月份低,下游溶解氧含量呈"凸"型,冬季12月、1月、2月份低。入河污染物的排放是影响溶解氧分布最重要的因素,其次,温度、径流量、支流水质状况等对溶解氧分布也产生一定影响。     

LATITUDINAL VARIATION OF DEEP SCATTERING LAYER IN THE WESTERN PACIFIC

The acoustic Echo Intensity (EI) was recorded with 38k shipborne Acoustic Doppler Current Profiler (ADCP) in the Western Pacific in four cruises between Sept. 2001 and Oct. 2002. The main Deep Scattering Layer (DSL) was observed at 400m-600 m depth in the four cruises. The latitudinal variation of the main DSL, which has high level of backscatter strength (BS) at high latitude, is prominent during both nighttime and daytime. The influences of environmental conditions on the DSL are discussed. Since high-oxygen water in the north is a friendly environment of marine animals which form the main DSL, more animals are expected to aggregate in the 400dbars-600dbars layer in the north. Dissolved Oxygen (DO) is the principal factor that causes the main DSL to vary with latitude, and its spatial distributions result from formation and transport of North Pacific Intermediate Water (NPIW).     

化学需氧量快速测定法和国标法对比研究

通过对化学需氧量快速测定法与GB 11914-89《水质化学需氧量的测定——重铬酸盐法》进行比对,从精密度、准确度等方面进行试验,验证了快速测定法在日常监测中能够代替国标法的可行性。     

某S135钻杆腐蚀穿孔失效分析

通过宏观形貌分析、力学性能测试、金相显微组织和微观形貌及物相分析,并结合钻杆的使用状况,对某S135钻杆管体穿孔失效原因进行了分析。结果表明,钻杆内加厚过渡区及紧邻的管体部分内壁的一侧集中分布着大量的深腐蚀坑,腐蚀坑主要是由于氧腐蚀形成的,钻杆的穿孔失效属于氧腐蚀失效。     

溶磷和pH值对杀真菌素链霉菌合成恩拉霉素的影响

研究了培养基灭菌后溶磷和发酵过程pH值等对杀真菌素链霉茵(Streptomyces fungicidicus)JZ-14-056D3合成恩拉霉素的影响,通过发酵尾气成分的测量和OUR,DO等参数的分析,发现培养基灭茵后溶磷质量浓度控制在0.65μg/mL,控制发酵过程pH值为7.0,192 h发酵单位最高可达5 710...     

电控汽车氧传感器的检测与诊断

在电喷发动机控制系统中,氧传感器作为关键的传感部件,同时又是控制燃油质量的关键部件。随着节能减排的不断推进,氧传感器的作用日益凸显。本文通过对氧传感器进行详细分析,同时对汽车上的氧传感器进行论述,进而为电控汽车氧传感器的检修和诊断提供参考依据。     

INVERTEBRATE AND FISH ASSEMBLAGE RELATIONS TO DISSOLVED OXYGEN MINIMA IN LOWLAND STREAMS OF SOUTHWESTERN LOUISIANA

Dissolved oxygen (DO) concentrations in lowland streams are naturally lower than those in upland streams; however, in some regions where monitoring data are lacking, DO criteria originally established for upland streams have been applied to lowland streams. This study investigated the DO concentrations at which fish and invertebrate assemblages at 35 sites located on lowland streams in southwestern Louisiana began to demonstrate biological thresholds. Average threshold values for taxa richness, diversity and abundance metrics were 2.6 and 2.3 mg/L for the invertebrate and fish assemblages, respectively. These thresholds are approximately twice the DO concentration that some native fish species are capable of tolerating and are comparable with DO criteria that have been recently applied to some coastal streams in Louisiana and Texas. DO minima >2.5 mg/L were favoured for all but extremely tolerant taxa. Extremely tolerant taxa had respiratory adaptations that gave them a competitive advantage, and their success when DO minima were <2 mg/L could be related more to reductions in competition or predation than to DO concentration directly. DO generally had an inverse relation to the amount of agriculture in the buffer area; however, DO concentrations at sites with both low and high amounts of agriculture (including three least‐disturbed sites) declined to <2.5 mg/L. Thus, although DO fell below a concentration that was identified as an approximate biological threshold, sources of this condition were sometimes natural (allochthonous material) and had little relation to anthropogenic activity. Copyright © 2012 John Wiley & Sons, Ltd.     

论储粮技术有利于粮仓防火安全

灭火系统不论是人工操作的消火栓系统或自动动作的喷水灭火系统、水喷雾灭火系统和气体灭火系统,无一例外的都是在火灾发生后,灭火系统才进行扑救,这种方式必然存在火灾损失,同时还伴随有水渍损失和污染损失。而防火系统则是使火灾不能发生,从而将防火从被动、消极状态转化为主动、积极状态。如何在粮食仓库采用防火而不是灭火？通过对燃烧条件的分析,结合粮食储粮技术情况,论述了现代储粮技术有利于粮库的安全防火。     

高压氧的应用以及安全使用探讨

文章探讨了在高压氧使用中应注意的几个关键因素,为促进高压氧的安全使用提供了经验积累。