基于反赋权与MBCT-SR多维云模型算法岩爆预测研究

基于岩爆事故的模糊性与随机性特征,为解决在当前岩爆烈度等级预测研究中,通过正向云发生器经验式计算多维云模型特征值进而导致预测结果主观性较强的问题.本文选取应力比Ts=σθ/σt、岩石脆性指数B=σc/σt以及弹性应变储能指数Wet作为评价指标,结合机器学习理论,采用多维逆向MBCT-SR云发生器算法对岩爆等级进行预测,...     

天然气汽车加气站压缩机房火灾爆炸事故故障树分析

压缩天然气汽车加气站压缩机房具有高压、易泄漏、易爆炸等危险性特点。根据其运行的实际情况,对压缩机房火灾爆炸事故原因运用故障树进行了深入分析,提出了压缩机房火灾爆炸事故预防对策。     

观历史印尼的几次大地震

印尼苏门答腊南部海域地震 1994年2月16日0时07分,印尼苏门答腊南部发生里氏6．5级地震。震中位于首都雅加达西北250公里,直落勿洞西北36公里处的海域,震源深度为58公里。地震造成215人死亡,3000多人受伤,40010多间房屋彻底被毁,6500座建筑物遭到不同程度的破坏;数以万计的人无家归;震后又降起大雨,多处山体发生塌方,交通、电力和通讯中断,经济损失达1．7亿美元。距里哇市24公里拥有近千名居民的辛加岛还遭到了海啸的袭击,致使150人丧生。     

AB法在虹桥污水处理厂的应用

乌鲁木齐虹桥污水处理厂采用AB活性污泥工艺,设计处理污水3×104m3/d,介绍了虹桥污水处理厂的工艺流程、设计参数、主要处理构筑物、运行状况、影响因素,并对AB活性污泥法的发展运行状况进行了分析和探讨。     

超临界水氧化法处理制浆黑液

造纸黑液是较难处理的工业废水。以工业纯氧为氧化剂,采用自制的间歇式超临界水氧化系统对麦草制浆黑液进行处理,根据实验数据分析了超临界水氧化过程中不同反应温度,时间,氧气浓度对该废水COD处理效率的影响。实验结果表明,选定合理的实验参数,COD去除率可达99.8%。     

三种类型森林林下植物多样性及生物量比较

对相同立地条件下海南天然次生林、桉树和马占相思林的林下植物多样性及生物量进行调查,通过比较,灌木植物的物种丰富度S、多样性Simpson指数、Shannon-wiener指数,Margalef指数、均匀度Pielou指数为:天然次生林＞桉树人工林＞马占相思人工林,方差分析前两者之间差异不显著,后两者之间差异极显著;而草本植物的变化趋势为:桉树人工林＞天然次生林＞马占相思人工林,方差分析结果前二者间除均匀度Pielou指数差异不显著外,其它多样性指数间差异极显著,后二者间差异不显著.灌木植物地上部分总生物量的变化趋势为:天然次生林＞桉树人工林＞马占相思人工林,草本植物的变化趋势为:桉树人工林＞马占相思人工林＞天然次生林.     

Catalytic decomposition of low level ozone with gold nanoparticles supported on activated carbon

Highly dispersed gold nanoparticles were supported on coal-based activated carbon (AC) by a sol immobilization method and were used to investigate their catalytic activity for low-level ozone decomposition at ambient temperature. Nitrogen adsorption-desorption, scanning electron microscope (SEM), and X-ray photoelectron spectroscopy (XPS) were used to characterize the catalysts before and after ozone decomposition. The results showed that the supported gold nanoparticles prepared with microwave heating were much smaller and more uniformly dispersed on the activated carbon than those prepared with traditional conduction heating, exhibiting higher catalytic activity for ozone decomposition. The pH values of gold precursor solution significantly influenced the catalytic activity of supported gold for ozone decomposition, and the best pH value was 8. In the case of space velocity of 120000h⁻¹, inlet ozone concentration of 50mg/m³, and relative humidity of 45%, the Au/AC catalyst maintained the ozone removal ratio at 90.7% after 2500min. After being used for ozone decomposition, the surface carbon of the catalyst was partly oxidized and the oxygen content increased accordingly, while its specific surface area and pore volume only decreased a little. Ozone was mainly catalytically decomposed by the gold nanoparticles supported on the activated carbon.     

Fate of proteins of waste activated sludge during thermal alkali pretreatment in terms of sludge protein recovery

Maillard reaction between reducing sugars and amides happened during pretreatment. Over 90 min of TAH at the optimal condition, 67.59% sludge proteins was solubilized. 15.84% soluble proteins broke down to materials with small molecular weight. Proteins are the major organic component s of waste activated sludge (WAS); the recovery of sludge proteins is economically valuable. To efficiently recover sludge proteins, WAS should undergo hydrolysis pretreatment to fully release proteins from sludge flocs and microbial cells into aqueous phase. One of the most widely used chemical methods for that is thermal alkali hydrolysis (TAH). Here, the soluble protein concentration achieved the highest level over 90 min of TAH pretreatment at 80°C; the sludge floc disintegration and microbial cell destruction were maximized according to the content profiles of bound extracellular polymeric substance (EPS) and ribonucleic acid (RNA) of sludge. Both less proteins broken down to materials with small molecular weight and less melanoidin generated were responsible. TAH pretreatment at 80°C for 90 min resulted in the solubilization of 67.59% of sludge proteins. 34.64% of solubilized proteins was present in soluble high molecular; 1.55% and 4.85% broke down to polypeptides and amino acids. The lost proteins via being converted to ammonium and nitrate nitrogen accounted for 9.44% of solubilized proteins. It was important to understand the fate of sludge proteins during TAH pretreatment in terms of protein recovery, which would be helpful for designing the downstream protein separation method and its potential application.     

石灰湿式脱硫新型添加剂研究

在恒温器中利用工业上常见的工业原料合成高分子物质,筛选出溶解性能合格的高分子物质作为脱硫添加剂,对添加剂的缓冲性能进行了系列研究,并且在液气比L／Q=5．0、石灰浆质量分数w=3％的条件下,对二氧化硫烟气进行脱硫对比试验研究。结果表明：添加剂作用效果明显,具有很强的缓冲性能;添加一定量的添加剂,脱硫效率上升4％;添加剂还具有一定的缓冲功能。     

浅析北京地铁的灭火救援

本文介绍了北京地铁的运营及灭火救援准备工作现状,指出了一些影响灭火救援工作的问题,并提出了相应的解决方法.