中美两国汽车驾驶安全影响因素研究

影响汽车驾驶安全的各国道路交通系统以及驾驶员的驾驶行为等存在着差异性 ,许多差异可以通过统计数据的分析 ,或者其他定量研究方法获取 ,但仍然有许多影响驾驶安全的因素难以发现。笔者通过焦点团体座谈会的方法 ,从驾驶者的角度 ,搜集并分析了中美两国驾驶安全的主要影响因素 ,以及具有美国驾驶经历会对我国驾驶员有何影响。通过中美两国定性数据的对比分析 ,得出了主要影响因素 ,与此同时 ,通过问卷调查定量地分析了这些因素的严重程度。     

Deterioration of Polyamideamine–Epichlorohydrin (PAE) in Aqueous Solutions During Storage: Structural Changes of PAE

Structural changes of polyamideamine–epichlorohydrin (PAE) in solution during storage at 4 °C and pH 4.2–4.5 for up to 8.9 years were studied by ¹H- and ¹³C-NMR analyses, colloidal titration and others. NMR signals due to 3-hydroxy-azetidinium groups of PAE decreased during storage, and correspondingly 2, 3-dihydroxypropyl groups were formed by the ring opening. The content of 3-hydroxy-azetidinium groups in PAE determined by ¹H-NMR were similar to that determined by the colloidal titration, although the former was higher than the latter. About 50% of the 3-hydroxy-azetidinium groups present in the fresh PAE were lost during storage for 8.9 years. Furthermore, ¹³C-NMR analysis revealed that significant depolymerization of polyamideamine chains occurred by hydrolysis of the amide linkages during storage. Rough evaluation of number average degree of polymerization (DPn) of the amideamine repeating unit showed that the DPn decreased from 12 to 2 during storage for 8.9 years.     

Prediction of dust cloud minimum ignition energy for organic dusts from modified hartmann tube data

The modified Hartmann tube apparatus is recognized to give realistic or safe indications of dust explosion violence. Evidence is presented that results from this apparatus can also be used to indicate minimum ignition energy. Published data show a correlation between minimum ignition energy and minimum explosible concentration, which is refined by also taking into account explosive violence. An empirical model has been derived, relating minimum ignition energy to minimum explosible concentration and explosive violence. The model allows estimation of probabilities of minimum ignition energy falling below specified values, such as those recognized as of practical importance by the relevant British Standard. A limited test of the model suggests that it can be applied to modified Hartmann tube data. It is anticipated that the model will be valuable as a screening tool, especially in the early stages of development of a project.     

改性钢渣除磷试验研究

研究了改性钢渣的吸附除磷效果。试验结果表明，钢渣对废水中的磷的去除率较高，当废水中磷质量浓度为10mg／L，pH值为弱酸或弱碱性条件下，钢渣的用量1g/100mL时，在15min内就可使残留液质量浓度降低到0．1mg／L，远远低于国家排放标准，去除率达到99％以上，对水体富营养化处理具有很重要的意义。     

抓好班组长培训夯实安全生产基础

班组长综合素质的高低,可影响安全生产.试图通过叙述抓好班组长培训与搞好安全生产的辩证关系,以期引起工业企业对抓好班组长培训工作的重视.     

改性凹凸棒土及粉末活性炭助凝聚硅硫酸铝消除微污染水中有机氯

以硅酸钠和硫酸铝为原料制备了聚硅硫酸铝絮凝剂(PASS),采用强化混凝的处理方法,对微污染水中有机氯(OCPs)的消除进行了研究.同时,考察了混凝剂投加量、pH值、原水浊度、粉末活性炭和改性凹凸棒土助凝剂等因素对OCPs消除效果的影响.结果表明:PASS投加量为5 mg·L-1时,OCPs的去除率可以达到57%~87%,浊度去除率可以达到99.1%,其效果好于聚合氯化铝(PAC);PASS混凝处理OCPs的最佳pH值范围是6~7;OCPs的去除与浊度的去除具有显著相关性,原水浊度的大小会影响OCPs的去除,低浊条件下OCPs和浊度的去除率明显低于中浊和高浊条件;粉末活性炭和改性凹凸棒土作为助凝剂与PASS复配均可显著提高OCPs的去除率,分别达到78%~100%和72%~95%.相较而言,凹凸棒土储量丰富,廉价易得,因此,以改性凹凸棒土替代粉末活性炭更有优势.     

碳纳米管修饰电极电催化还原去除废水中的氯霉素

为发展废水中抗生素的处理技术、保护水环境质量,采用表面活性剂辅助分散碳纳米管,制备碳纳米管修饰电极,研究了修饰电极对氯霉素的电催化还原能力和动力学特征,初步探讨了氯霉素的还原去除机制.结果表明,双十六烷基磷酸(DHP)可以有效分散碳纳米管,通过优化碳纳米管和DHP的配比、分散液修饰量,制备的碳纳米管修饰电极还原2 mg·L~(-1)氯霉素24 h时的去除率达到97.21%;电催化还原氯霉素的动力学过程符合一级反应动力学模型,去除速率常数为0.157 4 h~(-1),半衰期为4.40 h.采用液相色谱-串联质谱分析法(LC-MS/MS)鉴定了氯霉素的还原产物,分析了氯霉素还原的可能途径,电催化不仅还原了氯霉素中的硝基,还可以进一步还原羰基和脱氯,显著降低氯霉素的毒性.     

应用亲电型悬浮生物载体处理工业废水的现场中试

研究采用本课题组研发的亲电改性聚乙烯为悬浮生物膜载体,构建移动生物膜与活性污泥复合工艺(integrated free-floating biofilm and activated sludge,IFFAS),对东北某工业园区污水处理厂的污水处理进行现场中试。结果表明,当进水ρ(COD)、ρ(NH3-N)、ρ(TN)分别为139~741,19.3~44.9,29.6~148.6 mg/L时,改性载体在10 d左右即可完成挂膜;中试IFFAS工艺稳定运行阶段,出水COD、NH3-N、TN的平均去除率分别高达88%、97%、80%,出水浓度分别为36~48,0.1~0.9,5~14.3 mg/L,达到GB 18918—2002《城镇污水处理厂污染物排放标准》一级A排放标准。出水水质明显优于污水处理厂原有A2/O工艺出水,说明以亲电改性聚乙烯为载体的IFFAS工艺可显著提高净化污水的能力。     

活性炭负载二氧化锰的制备及其对罗丹明B吸附效能

采用颗粒活性炭(GAC)以共沉淀和热分解法制备了改性活性炭(MnO_2-AC),并采用SEM、XRD表征手段对改性前后活性炭进行微观分析;进而研究了GAC和MnO_2-AC随染料初始浓度、活性碳投加量、温度、吸附时间变化对染料废水罗丹明B的吸附效果影响。结果表明:GAC经改性后,活性炭表面变得粗糙,并有MnO_2产生。在MnO_2-AC投加量为0.2 g,罗丹明B浓度为100 mg/L,温度为25℃条件下反应12 h,其吸附量达到36.80 mg/g。另外,MnO_2-AC对罗丹明B的吸附过程符合Langmuir等温模型,并遵循准二级动力学模型。     

载氧化镁水生植物生物炭的特性表征及对水中磷的吸附

为去除富营养化水体中的磷并实现水生植物的资源化利用,以水生植物芦苇和互花米草为原材料,通过MgCl_2改性制备了不同Mg~(2+)和植物配比的共12种生物炭,考察对水体中磷的吸附能力及镁改性前后生物炭特性的差异.结果表明,当Mg~(2+)与芦苇、Mg~(2+)与互花米草的质量比为0.48、0.36时,制得的两种生物炭对20 mg·L~(-1)磷的吸附能力最强,分别为8.52 mg·g~(-1)和9.21 mg·g~(-1),是未改性时的79倍和66倍;对溶液中20mg·L~(-1)磷的去除率分别达到85.2%和92.1%.改性后芦苇和互花米草生物炭C、H、N含量减少,Mg含量分别增加到22.77%和23.46%.芦苇生物炭改性后比表面积减小了118.71 m~2·g~(-1),互花米草生物炭增加了22.59 m2·g~(-1);二者孔容和平均孔径均有所增加.改性前后生物炭的表面官能团种类相同.XRD测试指出MgO为改性生物炭的复合纳米颗粒中最主要的晶相;SEM展现了布满MgO的改性生物炭表面及孔道.机理分析表明,MgO是生物炭吸附磷的关键.