含高浓度 SO42-有机废水混合处理实验研究

研究了含高浓度SO42-废水和农药废水混合进行厌氧处理的工艺,对产气量,COD, SO42-, S2-, TVA, pH 等控制指标进行监测,并在实际工程中得到应用,证明该工艺可行的.     

Lead Phytostabilization and Cationic Micronutrient Uptake by Maize as Influenced by Pb Levels and Application of Low Molecular Weight Organic Acids

ABSTRACT

Phytoremediation is a promising technique to clean up toxic heavy metals including lead (Pb). A greenhouse trial was conducted to evaluate the effectiveness of citric, succinic, malonic and oxalic acids on micronutrient uptake and phytoremediation of Pb contaminated soil by maize under different Pb levels. Mean root and shoot dry weights of maize decreased with increasing Pb levels. At the lowest Pb level, application of citric and oxalic acids caused increase effects on root and shoot dry weight, respectively, as compared to the absence of organic acid. As Pb levels increased, micronutrient uptake in maize shoot decreased. Among the studied organic acids, only the application of oxalic acid increased uptake of all micronutrients in maize shoot as compared to control at the lowest Pb level. Mean root and shoot Pb concentration and uptake and also uptake index noticeably increased at the highest Pb level. All tested acids increased Pb concentration and uptake in maize root. At the highest Pb level, organic acids, except for citric acid, significantly increased shoot Pb uptake and uptake index as compared to the absence of organic acid. Translocation factors less than 1, demonstrated that most of Pb taken up by maize accumulated in root as compared to shoot. According to results reported herein, application of malonic, succinic and oxalic acids is a good strategy to enhance phytostabilization potential of Pb by maize in pb-polluted soils.     

马来酸酐接枝PP/PE共混物及其木塑复合材料

通过聚丙烯(PP)与聚乙烯(PE)机械混合来模拟废旧塑料混合物,利用马来酸酐(MAH)对PP/PE混合物进行接枝改性,然后以接枝共混物作为基体与木纤维复合制备木塑复合材料。通过对比接枝前后的红外光谱图,证明MAH已成功接枝在PP/PE共混物上。力学测试结果显示:基体经过接枝改性后,复合材料的弯曲强度和无缺口冲击强度均大幅度升高,当MAH用量为1%时,弯曲强度提高了50.4%,无缺口冲击强度提高了90.8%,而以废旧塑料为原料制备的复合材料的弯曲强度和无缺口冲击强度分别提高40.2%和53.4%。微观相形态分析表明:通过接枝改性不仅改善了PP/PE共混体系的相容性,同时也显著改善了木纤维与PP/PE共混物之间的界面结合状况,因而宏观上表现为力学性能提高。这表明,共混接枝改性方法可能是利用混合废旧塑料制备高性能木塑复合材料的一条可行途径。     

Endogenous organic acid variations in different chickpea (Cicer arietinum L.) genotypes

Abstract

Changes in cropping systems during the past century have led to selective pressure on weed flora. Species and ecotypes with characteristics enabling them to survive in high-input farmland have increased in numbers, at the cost of plants lacking these characters. Since the 1950s, the perennial weed species Cirsium arvense (L.) Scop. and Sonchus arvensis L. have mainly been controlled by the herbicide group synthetic auxins like MCPA. During recent decades, C. arvense seems to have become less susceptible to MCPA in both Europe and North America but the reasons are unclear.

To study the importance of selective pressure on weed ecotypes, both short- and long-term studies were carried out in Uppsala, Sweden. The first consisted of two growth-characteristic greenhouse experiments. The hypothesis was that ecotypes of C. arvense and S. arvensis from high-input farmland were different and displayed a more competitive growth pattern than did ecotypes from low-input farmland.

The second study was a field experiment with four ecotypes of C. arvense from low-input farmland to study if selective pressure was in force, over a period of six years. The four ecotypes had different growth characteristics and herbicide sensitivity and they were exposed to crop competition and MCPA treatments during the experimental period. The hypothesis was that ecotypes with a more competitive growth pattern and MCPA tolerance would survive to a greater extent than would other ecotypes. For C. arvense, the results from the growth-characteristic experiment showed that the growth pattern of ecotypes from high-input farmland differed, showing a more directly elongated growth pattern with fewer spines on the leaves compared with ecotypes from low-input farmland, which usually were of rosette-type. Results from the field experiment with C. arvense showed that after six years MCPA-sensitive and/or rosette-type ecotypes had almost disappeared while ecotypes with a more directly elongated growth pattern and less sensitive to MCPA survived to a much greater extent. The conclusion was therefore that when exposed to selective pressure like crop competition and herbicide treatments, ecotypes of C. arvense with a more directly elongated growth pattern and less sensitive to herbicide treatment survived to a greater extent compared with ecotypes missing these traits. Ecotypes from high-input farmland had generally fewer leaf spines than did ecotypes from low-input farmland. This may suggest a trade-off between spine formation and rapid competitive growth. In the growth-characteristic experiment with S. arvensis, no differences between ecotypes from high- and low-input farmland regarding growth characteristics or leaf spines could be detected. This might partly be due to a lower exposure of S. arvensis to selective pressure compared with C. arvense, since S. arvensis generally is less sensitive to MCPA.     

抗应激药物对蛋鸡育雏效果的研究

300只母雏随机均分为6组，其中Ⅵ组为对照组，Ⅰ、Ⅱ、Ⅲ、Ⅳ组钦水中分别添加1g/L速补-14、50mg/L维生素C 500mg/L丁二酸钠、100mg/L维生素C和100mg/L丁二酸钠，V组饲料中添加0.15%Vc银翘片，每组两个重复。结果表明：5个试验组鸡的日增重、饲料转化率、均匀度、成活率均明显高于对照组（P＜0.05)。综合比较5种抗应激药物添加效果是：银翘片C＞维生素C＞维生素C 丁二酸钠＞速补-14＞丁二酸钠。Vc银翘片是值得开发的中草药饮料添加剂。     

玉米籽皮稀酸水解液脱毒发酵制备丁二酸的可行性

丁二酸是一种重要的碳四平台化合物,利用非粮生物质替代淀粉制备丁二酸可保证粮食安全并降低原料成本。玉米籽皮是一种廉价的非粮生物质,该文采用稀酸水解玉米籽皮制备混合糖液,并对玉米籽皮稀酸水解液的脱毒条件进行了优化,优化结果为：活性炭用量1%（m/V）、pH4.0、作用温度30℃、作用时间30 min。在此工艺条件下,水解液的脱色率为92.27%,糠醛脱除率75%,5-羟甲基糠醛脱除率53%,多酚类化合物脱除率98%,总糖损失低于5%。经过脱毒处理后,产琥珀酸放线杆菌 NJ113均能利用水解液中的葡萄糖、木糖、阿拉伯糖,培养基总糖浓度为50 g/L时,丁二酸分批发酵的质量收率可达0.68 g/g,浓度可达34.2 g/L,生产强度达0.83 g/(L·h),总糖浓度为68.2 g/L时,丁二酸质量收率仍可达0.62 g/g,浓度42.3 g/L,生产强度0.98 g/(L·h)。发酵试验表明脱毒的玉米籽皮稀酸水解液作为碳源厌氧发酵制备丁二酸具有可行性。     

Plasticization of cellulose derivatives by reactive plasticizers II: characterization of plasticized cellulose acetates and their biodegradability

A plasticization method for cellulose acetates (CAs) has been developed that is based on the reaction with dibasic acid anhydrides and monoepoxides during the melting processing. As a continuation of the discussion in the previous report, additional evidence is presented for the role of grafting oligoesters onto cellulose acetates to prevent the bleeding of homo-oligoesters from the inside of molded articles to their surface. Based on these results, a method for enhancing the amount of grafting has been pursued by varying the combination of dibasic acid anhydrides and monoepoxides. The resulting reactive meltprocessing method allows preparation of biodegradable cellulosic plastics using practical process conditions. Higher biodegradability has been found for the oligoester-grafted CAs than for the unmodified parent CAs.     

4-溴邻苯二甲酸二异辛酯的合成

[目的]考察4-溴邻苯二甲酸二异辛酯的合成工艺条件。[方法]以苯酐、溴素及异辛醇为主要起始原料,经溴化反应得到4-溴邻苯二甲酸,再经酯化反应合成4-溴邻苯二甲酸二异辛酯。通过考察原料的摩尔比、反应时间及催化剂用量等关键因素对试验结果的影响,研究合成的优化条件。[结果]酯化反应中较优的合成条件是：催化剂浓硫酸的用量为总原料质量的4％,4-溴邻苯二甲酸与异辛醇的摩尔比为1：5,反应时间为5h,以苯酐计产品的综合收率为87．13％,试验所得产品经气相色谱分析含量在昕％以上,产品结构经^1H—NMR分析确定与目标产物相符。[结论]产物的表征为,4-溴邻苯二甲酸,^1H—NMR（D2O）：8．52（s,1H）;8．23（s,1H）;7．98（s,1H）;4-溴邻苯二甲酸二异辛酯,^1H—NMR（CDCl3）：8．25（s,1H）;7．97（s,1H）;7．73（s,1H）;4．20—4．28（m,4H）;2．05～2．12（m,2H）;1．25～1．33（m,16H）：0．94～0．99（12H）。     

聚氯乙烯/聚乙烯蜡接枝马来酸酐/竹粉复合材料制备的研究

用自制的聚乙烯蜡接枝马来酸酐(PEW-g-MAH)改性竹粉填充聚氯乙烯(PVC),制备PVC/PEW-g-MAH/竹粉复合材料.通过正交设计法探讨PEW-g-MAH接枝率及用量、竹粉粒径及用量对复合材料力学性能的影响.结果表明,在100gPVC中,加入用0.3g接枝率为1.16%的PEW-g-MAH改性的0.425mm竹粉30g,可得到力学性能较好的PVC/PEW-g-MAH/竹粉复合材料.其拉伸强度和缺口冲击强度分别由添加等量未改性竹粉体系的28.6MPa和3.05kJ/m2提高到30.01MPa和3.86kJ/m2.     

蔗渣纤维与丁二酸酐反应的研究

以蔗渣为原料,探讨了丁二酸酐改性的影响因素,并采用FT-IR半定量法进行了表征。研究发现,采用丁二酸酐直接处理蔗渣可以将羧基引入蔗渣中,羧基化的程度随着反应时间、酸酐用量、反应温度的提高而提高。在超声波处理时间30 m in、反应时间60 m in、反应温度115℃、丁二酸酐与蔗渣质量比1.25∶1的条件下,蔗渣与环状酸酐反应后的质量提高百分数(WPG)为39.4%。采用CP/MAS13C NMR对反应前后的蔗渣试样进行了表征,探讨了反应机理,发现反应后纤维素结晶指数降低,表明碳水化合物和木质素均参与了化学反应。