前缘增生组合式滑坡群的发育特征与形成机理

通过采用系统论理念和构造体系观点来研究滑坡群,指出前缘增生组合式滑坡群是最新研究认识的3种基本型式滑坡群中较简单、较常见、较重要的类型;并介绍了该类型滑坡群的平面组合、构图特点和发育特征,分析、探讨了该类型滑坡群的形成条件、形成机理及演化过程;揭晓了增生滑坡为什么会出现在老滑坡或古滑坡的某一特定部位这一滑坡群研究的核心或关键问题,认为解决这一问题就可以把握增生滑体出现在什么部位的规律,从而可为较大尺度滑坡灾害的风险评估和预测、预警分析提供必要的依据。     

负载型纳米金催化剂对室内空气中甲醛的去除

采用沉积-沉淀法(deposition precipitation,简称DP法)和共沉淀法(coprecipitation,简称 CP法)制备了负载型纳米金催化荆Au/Fe2O3,催化剂中金含量(质量分数)小于1%.并以甲醛完全氧化反应作为研究的目标反应.这个反应可以有效地去除室内空气中的有害成分甲醛.通过催化活性的测试和XRD、TEM、TPR等技术对催化剂进行了表征.结果表明,两种方法制备的催化剂有各自的优势和特点,其中DP法制备的催化剂金含量(质量分数)只有0.67%的情况下,经过条件优化,甲醛完全转化温度为80℃,是一个较好的结果;而CP法制备的样品有较好的抗热性,可能有利于催化剂的使用寿命.因此,本工作为该类催化剂实用化提供了有价值的信息和依据.     

Effect of background electrolytes on the adsorption of nitroaromatic compounds onto bentonite

To further elucidate interaction of nitroaromatic compounds with mineral surface, the sorption of m-dinitrobenzene (m-DNB) and nitrobenzene to original bentonite in aqueous solution containing di erent electrolytes (i.e., KCl, NH4Cl, CaCl2 and Tetramethylammonium bromide (TMAB)) was studied. The sorption of m-DNB was greatly enhanced with the presence of KCl and NH4Cl, while little influence was observed with CaCl2 and TMAB, following the order of KCl > NH4Cl TMAB, CaCl2, or DI water. For nitrobenzene, sorption enhancement only occurred at high nitrobenzene concentrations in the presence of KCl, and the solute equilibrium concentration at inflexion point was lowered with increasing KCl concentration. These sorption enhancements were significantly promoted with the increase of electrolyte concentration. The salting-out e ect is insu cient to account for the sorption enhancement by original bentonite with increasing KCl or NH4Cl concentration. X-ray di raction patterns of bentonite suspensions indicated that the sorption enhancement of m-DNB was attributed to the intercalation of K+ or NH4 + into bentonite interlayer and then dehydration with m-DNB to form inner-sphere complexes, which caused previously expanded bentonite interlayers to collapse in aqueous suspension, thus further enhanced the interaction of phenyl with siloxane surface. In comparison, the sorption enhancement of NB is attributed to the formation of outer-sphere complexes with K+ at high solute-loadings (> 200–400 mg/kg). The sorption of m-DNB to initially modified TMA+-bentonite and K+-bentonite was almost the same as respective sorption to original bentonite in solution containing TMA+ and K+.     

危险废物焚烧烟气净化工艺研究

通过实际工程分析了危险废物焚烧烟气的特性及烟气净化工艺的选择方法,探讨了湿法喷淋塔吸收剂的选取、喷淋吸收后浆液处理,同时分析探讨了烟气净化工艺的各段操作温度如何设定。     

新型旋切式气液两相喷嘴及内部流场数值模拟

本文在对各种气动性喷嘴及其雾化机理分析的基础上提出一种新型雾化喷嘴--旋切式气液两相喷嘴。该喷嘴具有结构简单、喷雾量无限可调、喷雾锥角调整灵活、防堵塞、雾化效果好的优点。通过CFD数值模拟研究发现,在旋切式喷嘴内部液流已经被气流剪切雾化成细小颗粒,其均匀的分散在气流中,在混合室内部形成气液混合流,形成一次雾化。当气液混合流脉冲喷出孔喷时,体积进一步膨胀,同时,高速液滴外部空气相互作用,产生二次雾化,促进了雾化效果。     

黑龙江省中小城镇污水处理现状分析

随着经济社会发展水平的不断进步,黑龙江省内主要干流及支流的水质也发生着相应的变化,特别是不断崛起的中小城镇,其产生并排放的污水给水环境带来巨大的压力,急需加快中小城镇污水处理厂建设,削减污染物负荷,改善相关水环境质量。     

核电厂密封段加速寿命试验研究

堆芯中子注量率测量系统是30万千瓦核电厂监测系统的重要组成部分之一。该系统中的密封段要在工作温度不大于100℃、设计压力为17.16 MPa条件下满足长期密封要求。根据Arrhenius定律及《机械密封试验方法》,计算出了保证密封段正常工作5 a不泄漏需在240℃条件下进行加速寿命试验所需的试验时间。同时还制定了密封段加速寿命试验方案并进行了加速寿命试验,对试验测量参数进行了分析。分析结果表明密封段满足正常工作5 a不泄漏的要求。密封段加速寿命试验是密封段型式试验的重要步骤,还可作为其它密封设备加速寿命试验的参考。     

地震动特征的统计分析

统计了国内外287次5级以上的实际地震记录,研究了地震动峰值不对称比、持时、地震荷载类型的统计特征和规律。结果表明：地震动峰值具有明显的不对称性,可以用峰值不对称比描述,统计结果具有规律性,其平均值总体上随震级加大而略有降低,从5级到8级地震其范围变化为1.4～1.2;地震动持时随震级增大而增大,近似于线性增长,震级从...     

Analysis of risk trade-off relationships between organic solvents and aqueous agents: case study of metal cleaning processes

When substance substitution is implemented to reduce the target risk of production processes, countervailing risks may occur. The goal of this study is to analyze the risk trade-off relationships between organic solvents and aqueous agents in the case study of metal cleaning processes. Global environmental impacts and local risks were evaluated for the eight scenarios by life cycle and risk assessments, respectively. The results show that the contribution of the processes using chlorinated solvents to photochemical ozone creation, human toxicity, ozone depletion, and ecotoxicity was larger than processes using aqueous detergents, while the contribution of aqueous processes to eutrophication was larger than chlorinated processes. Neighbors’ health risk around a cleaning site using chlorinated solvents was sufficiently small in all scenarios, whereas ecological risk due to surfactants which are contained in aqueous detergents and emitted to the local aquatic environment should be reduced. Cleansing agents and process facilities should be selected on the basis of the comprehensive analysis of risk trade-off relationships for feasible and cleaner production.     

亚热带红壤硝化特性的干土效应响应

风干处理常对土壤中的硝化细菌数量和活性造成显著影响.为研究土壤硝化作用的干土效应,以分别发育于第四纪红土(quaternary red earth,Q)和红砂岩(tertiary red sandstone,S),利用方式为水稻(rice,R)与旱地(upland,U)的4个农田土壤的新鲜土与风干土为供试材料,进行35d的室内培养试验.结果表明,对于无外源铵输入的处理而言,旱地土壤QU的新鲜土和风干土的硝化率分别为48%和54%,SU则分别为76%和78%,硝化作用的干土效应均不显著(p0.05);但干土效应却显著影响了水稻土的硝化作用(QR的新鲜土和风干土的硝化率分别为40%和89%,SR分别为76%和94%,p0.01),且其风干土样的硝化作用表现出明显的微生物激活过程.外源铵的加入促进了土壤的硝化作用强度且使得旱地土壤的干土效应显著,所有供试土壤新鲜土的硝化率均显著高于风干土的硝化率.总之,土壤利用方式显著影响了硝化作用对干土效应的响应,而且利用方式和加铵对硝化作用的干土效应有着极显著的交互作用.