基于模糊数学的四川省西充河水质评价

本文利用模糊数学法,选取溶解氧(DO)、5日生化需氧量(BOD5)、氨氮(NH4+-N)、总氮(TN)、总磷(TP)5项指标,对比四川省西充河雷打石和拉拉渡两个断面,对西充河2003～2010年水质进行评价。评价结果表明:2003～2010年西充河的水质为劣Ⅴ类,达不到国家要求的Ⅲ类水质标准;TN为西充河主要污染指标,西充河溶解氧偏低而氮和BOD5超标严重。为尽快使西充河的水质达标,对其进行有效治理迫在眉睫。     

典型城市污水处理厂污泥无机质含量及含砂率分析

对青岛5个典型城市污水处理厂污泥无机质含量与含砂率进行了调查研究,结果表明,以生活污水为主的A厂(90%为生活污水)和B厂(85%为生活污水)的污泥无机质含量在20%³0%,而以工业废水为主的C厂(50%为工业废水)、D厂(50%为工业废水)和E厂(70%为工业废水)的污泥无机质含量在50%30%,而以工业废水为主的C厂(50%为工业废水)、D厂(50%为工业废水)和E厂(70%为工业废水)的污泥无机质含量在50%⁷0%;各污水厂污泥含砂率相差较大,而且污泥无机质含量较高的C厂、D厂和E厂,其含砂率普遍较高,而污泥无机质含量较低的A厂和B厂,其含砂率也较低。对其中砂质进行粒径分布与显微检测分析,并对污泥含砂特性进行了深入探讨,结果表明,各污水处理厂污泥含砂主要为淡黄色硅质无机砂质颗粒和黑色磁性无机砂质颗粒,各污水处理厂污泥含砂属性主要与污水处理厂服务区域的地理环境以及进水性质有关。     

Starch/polyvinyl alcohol blended materials used as solid carbon source for tertiary denitrification of secondary effluent

Starch/polyvinyl alcohol （PVA） blended materials for using as a solid carbon source （SCS） were prepared by blending PVA and gelatinized starch in an aqueous solution system, in which PVA served as framework material and starch as carbon source. The optimization of starch content and temperature effects were investigated. It was indicated that higher denitrification efficiency could be achieved with more starch in the materials. The average specific denitrification rates were 0.93, 0.66, 0.37 and 0.36 mg/（g·day） corresponding to starch content of 70%, 60%, 40% and 30% respectively at 37℃. The denitrification rates increased when operating temperature was raised from 23℃ to 30℃ and then 37℃. The mechanism of carbon release was analyzed incorporating the experimental results of abiotic release in deionized water. The organic carbon was mainly hydrolyzed by microbes, and the biological release efficiencies were at the range of 89.2% to 96.0%. A long-term experiment with a continuous flow reactor with SCS material containing 70% starch was conducted to gain some experience for practical application. When the influent nitrate concentration was in the range of 35.2 to 39.1 mg/L, hydraulic retention time of 4 hr, and operating temperature of 30℃, a nitrogen removal efficiency up to 94.6% and denitrification rate of 0.217 kg/（m3.day） was achieved. The starch-based materials developed in this study can be used as a solid carbon source for tertiary nitrogen removal from secondary effluent.     

管-土相互作用模型试验的尺寸效应及可靠性分析

为了分析北京地区粉质黏土场地中管-土相互作用土弹簧模型参数,进行了一系列管土相互作用试验。由于人力、经费、场地等原因,模型箱尺寸无法取到无限大,模型箱的尺寸效应有可能使试验数据出现一定偏差。为了检验已开展模型试验结果的可靠性,基于ABAQUS有限元软件进行了数值仿真,探讨了土体的破坏模式,研究了管-土相互作用试验的尺寸效应,并得到如下结论:土体破坏模式可分为深埋和浅埋两种破坏模式;模型箱下方和后方边界对试验结果影响较小,当深径比大于6时,前方边界开始对试验结果产生影响。最后,分析和修正了试验结果并对类似试验中的模型箱尺寸选取给出了建议。     

春播一粒种 秋收一壶油--石油也可以种出来

据有关专家预测，地球上现有的矿物能源乐观估计也不过再用100年，加上科技文明的飞速发展，能耗的成倍增加，新的可再生能源的开发越来越紧迫地摆在人类面前。且不说矿物能源这种日趋枯竭的危机局面，仅从它们对环境的污染而言也足以令人扼腕了。人们长久期盼着能找到一种“石油植物”，像稻米的春种秋收一样，春播绿草，秋收石油。     

Zeolite (Na) modified by nano-Fe particles adsorbing phosphate in rainwater runoff

Zeolite (Na) modified by self-synthesized nano-Fe particles was used as infiltration media to adsorb phosphate in rainwater runoff. The adsorption capacities increased up to 75 times that of natural zeolite at a saturated equilibrium phosphate concentration of 0.42 mg/L. The correlation of capacity and material-specific surface area indicated that specific surface area was not the key factor contributing to the capacity improvement. SEM and XRD analysis showed that chemical reaction between Fe and P to form new products like cacoxenite is the main reason for the increased capacity, and that the method of adding metal ions or particles to improve the adsorption capacity for phosphate is feasible.     

河坝1井“三高”气井固定式节流阀的应用

通过对河坝1井高压区固定式节流阀在实际运用情况的分析,指出了“三高”气井的固定式节流阀选择为安全开采这类气井的关键,分析得出国产普通固定式节流阀不适合河坝1井高压节流的需要,改进的固定式节流阀基本能够满足生产需要,进口固定式节流阀完全能够满足生产需要,但这3种固定式节流阀流向均不符合API 6A要求,存在一定的安全隐患,提出了改进建议.     

某边坡地震工况下的稳定性数值模拟分析

地震是引起边坡失稳的重要因素之一,文章以怒江上游干流左岸一边坡为例,利用Flac3D软件对其在地震工况下的稳定性进行了数值模拟分析。通过对比得出:在天然工况下,边坡塑性区域分布范围较小且零星,剪应变增量和位移场分布均合理分布,边坡处于稳定状态;在地震工况下,塑性区域形成贯通面,剪应力增量集中分布在基岩与变形带分界面,并且位移大幅增加,此时边坡处于失稳破坏状态。文章对揭示边坡在地震作用下失稳机制提供有益参考。     

A survey and analysis on public awareness and performance for promoting circular economy in China: A case study from Tianjin

The main objective of this study is to create a better understanding of public awareness and performance in the promotion of a Circular Economy (CE) in Tianjin, China. The data and information used in this paper were collected by distributing questionnaires randomly in 6 urban districts and interviewing 600 respondents. The results indicate that the residents have limited awareness and a poor understanding about the CE program. However, they hold a positive attitude toward garbage sorting while most of the residents simply classify the garbage into categories that can be sold, reused or exchanged for new ones. People's awareness of the CE program has a positive correlation to their educational level, whereas their pro-environmental and resource conservation behavior has a positive correlation to the age of the respondents.     

IT公司员工薪酬激励方案

王燕是某IT公司信息产品事业部的人力资源经理,最近有件事令她比较头疼：公司里已有好几个业务骨干纷纷跳槽到了其他公司,公司员工之间私下也传,有几个能力比较强的员工也不太稳定,准备走人.