重金属吸附剂壳聚糖的改性研究进展

综述了重金属吸附剂壳聚糖改性研究的新进展,介绍了交联与接枝等改性方式对壳聚糖稳定性的影响及改性后的壳聚糖对水体中重金属离子吸附性能的改善.针对壳聚糖改性中仍然存在的一些问题,指出今后研究中值得关注的方向.     

Biofiltration treatment of odors from municipal solid waste treatment plants

An in situ compost biofilter was established for the treatment of odors from biostabilization processing of municipal solid waste. The concentrations of total volatile organic compounds (VOCs) in odors and their components were measured. Biofilter media was characterized in terms of total carbon (TC), total nitrogen (TN), total phosphorus (TP), organic matter (OM), pH value and determination of bacterial colony structure. Gas chromatography–mass spectrometry (GC–MS) analysis showed that the main components of the produced gas were benzene, toluene, ethylbenzene and xylene (BTEX) along with other alkanes, alkenes, terpenes, and sulphur compounds. The compost biofilter had remarkable removal ability for alkylated benzenes (>80%), but poor removal for terpenes (～30%). Total VOC concentrations in odors during the biostabilization process period ranged from 0.7 to 87 ppmv, and the VOC removal efficiency of the biofilter varied from 20% to 95%. After about 140 days operation, TN, TC, TP and OM in compost were kept almost stable, but the dissolved N, NH₄–N and NO₃–N experienced an increase of 44.5%, 56.2% and 76.3%, respectively. Dissolved P decreased by 27.3%. The pH value experienced an increase in the early period and finally varied from 7.38 to 8.08. Results of bacterial colony in packing material indicated that bacteria and mold colony counts increased, but yeasts and actinomyces decreased along with biofilter operation, which were respectively, 3.7, 3.4, 0.04 and 0.07 times of their initial values.     

膜蒸馏技术在石化废水处理领域的应用进展

综述了一种新型分离技术——膜蒸馏技术在石化废水处理领域的应用现状,重点介绍了在高盐度废水处理和挥发性有机物废水处理两个方面的进展;指出膜蒸馏应用过程中存在的主要问题是膜污染;预测了膜蒸馏及其集成技术在废水处理领域的发展前景。     

废聚碳酸酯水解法制双酚A

以1,4-二氧六环为溶剂、NaOH为催化剂,采用废聚碳酸酯(PC)常压水解法制双酚A(BPA).对反应影响因素进行了研究.实验结果表明,在反应温度为100℃、反应时间为8h、m(NaOH):m(水+溶剂)=1:33、m(溶剂):m(PC)=4:1、m(水):m(PC)=1:1的最佳反应条件下,PC水解率大于98%,BPA收率大于95%.     

N掺杂TiO_2光催化剂的制备及其H_2O_2改性的研究

以钛酸四丁酯为前驱物,采用水解沉淀法制备了N掺杂TiO_2光催化剂和H_2O_2改性的N掺杂TiO_2光催化剂.实验表明,H_2O_2改性的N掺杂TiO_2光催化剂的最佳制备条件为:氨水(质量分数28%)加入量20 mL,焙烧温度500 ℃,H_2O_2(质量分数30%)加入量2.0 mL.日光下,N掺杂TiO_2光催化剂及H_2O_2改性的N掺杂TiO_2光催化剂在反应90 min时的活性红紫去除率达99%,它们对活性红紫的去除率远高于P_(25)TiO_2光催化剂.H_2O_2改性的N掺杂TiO_2光催化剂中N质量分数比改性前明显提高,制备的两种催化剂中不仅含有N元素,同时还含有C和H元素.     

用电解锰阳极泥和含SO_2工业尾气制备硫酸锰

以电解锰阳极泥与电解锌生产中产生的含SO_2尾气为原料,经过反应、浸出、浸出液两次净化和浓缩结晶制备硫酸锰,考察了反应时间、含SO_2尾气的流量及反应温度对Mn~(4+)转化率的影响.实验结果表明:在反应时间45 min、反应温度20～30 ℃、含SO_2尾气流量16 L/min的条件下,Mn~(4+)转化率达90%以上;尾气中SO_2利用率随尾气流量增加而降低;所得MnSO_4·H_2O产品质量达到GB1622-86<工业级硫酸锰标准>.     

pH敏感性β-环糊精微球的制备及其吸附性能

采用反相微悬浮乳液聚合技术制备了β-环糊精(β-CD)微球,用丁二酸酐对β-CD微球进行化学改性,制备了pH敏感性β-CD(pH-β-CD)微球.通过傅里叶红外光谱仪和扫描电子显微镜对微球的结构、粒径和形貌进行了表征.探讨了亚甲基蓝模拟染料废水pH、吸附时间和微球加入量对亚甲基蓝吸附性能的影响.实验结果表明,在亚甲基蓝模拟染料废水pH为10.0、吸附时间为90 min的条件下,当pH-β-CD微球加入量为50 mg时,pH-β-CD微球吸附量为16.1 mg/g;当pH-β-CD微球加入量为250 mg时,pH-β-CD微球对亚甲基蓝的脱色率达96.2%.     

Methanolysis and Hydrolysis of Polycarbonate Under Moderate Conditions

Alkali-catalyzed methanolysis and hydrolysis of polycarbonate (PC) in a solvent in which PC can substantially dissolve such as N-methyl-2-pyrrolidone, 1,4-dioxane, tetrahydrofuran and so on were studied. Reaction conditions were optimized for the purpose of recycling PC in the form of bisphenol A and carbon carbonate. The results showed that both the methanolysis and hydrolysis of PC could take place under moderate conditions. Under the conditions of reaction temperature 40 °C, m(PC):m(MeOH) = 1:1, m(PC):m(NaOH) = 50:1, reaction time 35 min and using tetrahydrofuran as solvent, the methanolysis conversion of PC was almost 100% and the yield of bisphenol A was over 95%. Moreover, under the conditions of reaction temperature 100 °C, m(PC):m(H₂O) = 1:0.7, m(PC):m(NaOH) = 10:1, reaction time 8 h and using 1,4-dioxane as solvent, the hydrolysis conversion of PC was almost 100% and the yield of bisphenol A was over 94%.     

Integrated model of simulated occupant injury risk and real medical costs

Introduction

The purpose of this study was to develop an integrated methodology that links occupant injury risk functions, estimated in the laboratory, with real world medical treatment costs by using the abbreviated injury score (AIS). Using our model, the expected medical treatment costs for crash injuries to various body regions and of different severities can be investigated.

Methods

First, the simulation results are compared with NHTSA crash data. We used a modified kinematics simulation model that incorporates an F = E^b function as a supplement to the previous Steffan's model to obtain a more accurate acceleration history a(t). Second, head injury criteria HIC₃₆ can be calculated from a(t), and we use the injury probability P as a function of HIC_36, as proposed by Kuppa, to obtain the injury risk function for various AIS values. Third, medical treatment cost models for various AIS values can be calculated by using a regression cost model with real world data. Finally, the injury risk function and medical treatment cost models are linked through AIS values. We establish an integrated methodology and predict medical costs and car safety data using real world police reports, medical treatment costs, and laboratory simulation results.

Results

Using head injuries in frontal crashes as an example, we focus on simulation parameters for different vehicle models, with and without airbags. We specifically examine impact closing speed, Delta-V, and impact directions.

Conclusion

Simulation results can be used to supplement insufficient real crash data, in particular ΔV, and injury risk results from police crash reports.

Impact on industry

The proposed integrated methodology may provide the vehicle industry with a new safety assessment method. Real crash data coupling provides consumers with more realistic and applicable information.     

聚硅酸铝铁的合成及絮凝性能研究

以水玻璃、硫酸铝和硫酸铁为原料合成了聚硅酸铝铁,考察了硅酸活化pH值、(Al+Fe)/Si摩尔比、Al/Fe摩尔比、加入量、水样初始pH值等因素对PSAF絮凝性能的影响.PSAF的絮凝效果明显优于聚合氯化铝和硫酸铝,是一种新型无机高分子絮凝剂.