功能菌强化应急处理苯胺突发污染事故研究

近年来各种环境污染事故频发，据统计仅2001~2003年间，发生的各类环境污染事故就高达5606次，其中水污染事故3235次，占全部的57.7%。这些事故不仅给人民生命财产造成巨大损失，也给生态环境造成严重的破坏。因此开发安全高效的应急处理技术迫在眉睫。本研究以筛选高效苯胺降解菌为基础，通过对高效菌降解性能的研究指导将高效菌作为功能郡主投加到已有生物处理系统强化应急处理苯胺突发污染事故废液，取得了良好的效果。 苯胺高效降解菌AN-P1为红球菌（Rhodococcus sp.），其通过间位途径降解苯胺，AN-P1利用苯胺生长和降解的最佳pH为6，最适浓度为2000 mg/L，最适温度为30 ℃，最佳接种量为0.3‰。AN-P1降解含500 mg/L、1000 mg/L、2000 mg/L苯胺的培养物分别经过28 h、24 h、32 h降解，出水苯胺含量能达到《污水综合排放标准》（GB8978-1996）一级标准。但由于苯胺降解过程中释放了大量氨氮，出水氨氮仍较高未能达标排放。而常规SBR系统应急处理效果较差，苯胺和COD去除率均低于10%，出水未能达标排放。活性碳吸附后的回收和后续处理也会带来操作不变和二次污染问题，且处理后出水往往难于达标排放，尚需进行进一步处理。 生物处理系统应急处理后恢复运行处理效果监测和PCR-DGGE图谱分析显示，用AN-P1菌强化应急处理系统后不仅能快速高效的去除苯胺，而且可以有效保障处理系统对污染物的净化性能，有效的保护系统中的功能微生物免受苯胺毒害。 研究结果表明，从实际处理效果、对原有生物系统性能保护及实际应用操作等多方面考虑，用AN-P1菌强化应急处理苯胺突发污染事故在技术上都是可行的。本研究为应急处理苯胺突然污染事故废液提供了新的方法。 Recent years, environment pollution accidents happened frequently, the data showed that there are 5606 accidents between 2001 and 2003, including 3235 water environment accidents, which is 57.7% of all. These accedents not only caused money lost and life lost but also caused serious damage to the ecologicl environment. So exploring highly-effective and secure methods to solve these accidents is an urgent mission. We screened a highly-effective aniline-degrading bacterium and did some researches on its ability to degrade aniline, in order to guide the emergency treatment of aniline containing wastewater that caused by sudden accident pollution with bioaugmentation. A highly-effective aniline-degrading bacterium AN-P1 was isolate and characterized as Rhodococcus sp. It degrades aniline through meta-cleavage pathway. The optimal pH and temperature for cell growth and aniline degradation were 6 and 30 ℃, respectively, and the opitimal concentration of aniline was 2000 mg/L, the optimal inoculation amount was 0.3‰.It took bacterium AN-P1 only 18 h, 24 h and 32 h, respectively, for the treatment of MSB containing 500 mg/L, 1000 mg/L, 2000 mg/L aniline to meet the first grade of national some of the NH4+-N which caused by aniline degradation. It took bacterium AN-P1 only 10 h, 20 h and 32 h, respectively, for the treatment of wastewater containing 500 mg/L, 1000 mg/L, 2000 mg/L aniline to meet the first grade of national integrated wastewater discharge standard. The bacterium AN-P1 can also remove some of the NH4+-N which caused by aniline degradation. It took bacterium AN-P1 only 10 h, 20 h and 32 h, respectively, for the treatment of wastewater containing 500 mg/L, 1000 mg/L, 2000 mg/L aniline to meet the first grade of national integrated wastewater discharge standard. By combing AN-P1 with regular SBR system, it took only 36 h for the emergency treatment of wastewater containing 2000 mg/L aniline under simulating engineering conditions to meet the discharge standard. While the NH4+-N of effluent can not meet the standard because of the high amount NH4+-N caused by aniline degradation. The regular SBR system was not good at aniline and COD removal. The removal efficiency of which are less than 10%. It cost 67.8 g activated carbon to absorbed 1000 mg aniline. It is inconvenient to transport and use it for the emergency treatment of aniline when the sudden pollution accident happened. Meanwhile, it was complex ad hard to recycle the activated carbon and treat the aniline wastewater get from activated carbon recycling too. Hard to meet the effluent standard was also a problem of activated carbon absorption method. According to the PCR-DGGE profile and removal efficiency of pollutants and COD when the systerm recover from emergency treatment, AN-P1 can efficiently protect the microbial community of regular activated sludge system against the aniline. It proved that combing AN-P1 with regular biological system is a feasible strategy for emergency treatment of aniline sudden pollution accident. The research offered a new way for emergency treatment of aniline sudden pollution accident.

重离子束在微生物诱变育种及生物能源开发中的应用

作为一种新型的辐射诱变源,重离子束在辐射诱变育种中的优越性已经显现。在此基础上综述了重离子束用于微生物诱变育种的基本原理、独特优点、所取得的成果及研究进展,并对其在新型生物能源开发中的潜力进行了展望。

逆运动学弹性共振散射方法在非束缚核结构研究中的应用

简要介绍了近几年发展起来的厚靶逆运动学弹性共振散射方法在非稳定核结构测量中的应用。它是研究非束缚态核结构的实验方法之一。通过测量反冲轻核的激发函数,提取共振态的能量、自旋宇称和衰变宽度等。主要用于研究非稳定核素的结构、核天体物理中相关核的阈能共振态的能级参数测量等。

进一步指认近质子滴线核~(129)Pm的衰变

20 0 4年曾报道过利用4 0 Ca + 92 Mo融合蒸发反应产生了近质子滴线新核素12 9Pm ,并首次观测到它 (EC + β+)衰变产生的能量为 99keV的γ射线 .为了进一步确认上述指认 ,以下提供了三方面的新证据 :1)在 16 4— 190MeV能量范围内测量了 99keV衰变γ射线的激发函数 ;2 )进行了交叉反应36 Ar + 96 Ru的实验 ,观察到了相同的 99keV衰变γ射线 ;3)用Woods SaxonStrutinsky方法计算了12 9Pm的核势能面 ,其基态自旋宇称被预言为 5 / 2 - ,所以12 9Pm的 (EC + β+)衰变有利于馈送到子核12 9Nd的 5 / 2 - 的低位态 ,这也与前期报道相符 .

14MeV中子反应和远离核研究

指出了中子源的重要性,扼要地说明了加速器中子源的特点。简单地介绍了14 MeV中子引起的核反应,发现了14 MeV中子可以引起重核的奇异(n,2p)反应,并以此为基础,形成了合成和研究重丰中子新核素的一条物理思想和生成、分离鉴别技术路线;先后合成和研究了~(185)Hf、~(237)Th、~(175)Er和~(197)Os等四种重丰中子新核素。

2003年秋季西安大气中黑碳气溶胶的演化特征及其来源解析

IEECAS SKLLQG

一台300kV电子帘加速器辐照箱屏蔽物理设计

介绍一台电子能量为 30 0keV、束流强度为 6 0mA的电子帘加速器辐照箱的屏蔽物理设计。箱体厚度为 1.5cm的铅。

The stripper design and test at HIRFL-CSR

Charge stripping is employed to produce multi-charged ions for injecting the cooling storage ring After penetrating through the carbon foil, the widened distribution of ion charge states poses a limit to the ion injection Therefore, the carbon foil plays a key role in the charge snipping injection In this paper, foul strippers for Heavy Ion Research Facility at Lanzhou (HIRFL) and Cooling Sun age Ring (CSR) are introduced The charge state distribution of the stripped ions is measured and the stripping efficiency of the foils is investigated The experimental results are consistent with the theoretical values

丰中子新核素238Th的合成、鉴别和230Ac b 延发裂变的观测

新核素的合成及衰变性质的研究一直是核物理科学的前沿领域，它对于人类拓广对原子核运动规律的认识有着十分重要的意义。本文首先概述了新核素合成的意义、方法，并简要阐述了一种奇异的衰变方式—β~-延发裂变，为实验部分的论述提供理论基础。在实验部分，本文阐述了用放射化学方法研究了钍、钡、镭等复杂反应产物的化学分离。通过在Th的分离中引用PMBP萃取和反萃体系，并采用氧化还原体系有效地去除了绝大多数杂质元素，特别是非常好的去除了碘和溴离子的沾污，较好地完成了Th与其它反应产物的分离。对Ba、Ra的分离主要采用快速的阳离子交换流程，达到了满意的分离效果。对用中能~(18)O离子束照射铀、钍的反应产物进行分离，对分离出的钍、钡、镭样品进行了γ（X）单谱和时间序列谱测量。并对记录下来的样品的谱图进行了分析。使用上述方法，我们在兰州重离子加速器（HIRFL）上用~(18)O离子照射重铀酸铵靶，通过多核子转移反应，首次合成并鉴别了新核素不相识~(238)Th。 同时通过不同的反应道产生~(237)Th，并对~(237)Th的半衰期进行了测定；在HIRFL上用~(18)O离子照射氧化钍靶对~(230)Ra的子体~(230)Ac的β~-延发裂变现象进行了观测，在被Ra样品爆光的云母径迹探测器上观察到了两个裂变径迹，从ThO_2靶中用三次BaCl_2沉淀法分离出钡、使用γ谱学这技术测定了十多个Ba的放射性同位素的截面。

近垒及垒下能区重离子熔合-裂变反应机制的研究

本工作用固体云母核径迹探测器测量了质心能量为73.7至93.4MeV的~(16)O + ~(238)U和能量为57.9至76.0MeV的~(12)C + ~(237)Np系统熔合裂变碎片角分布和截面；首次用双栅位置灵敏雪崩计数器[DGAC]测量了质心能量为46.5至56.2 MeV的~(11)B + ~(238)U和能量为58.9至76.0 MeV的~(12)C + ~(237)Np及84.0MeV的~(16)O + ~(238)U系统熔合裂变碎片角关联和截面。研究结果表明：使用二种测量方法得到的熔合裂变截面和裂变碎片角分布是一致的，对于三个反应系统熔合裂变截面用考虑靶核形变的耦合道理论能得到合理的描述；而从计算熔合截面中提取穿透系数，从有限力程转动液滴模型中提取有效转动惯量，用鞍点过渡态理论计算裂变碎片角分布，发现裂变碎片角分布各向异性异常；随入射能量减少，各向异性并不是单调地变化，而是呈现异常的“鼓包”；裂变碎片各向异性还有明显的入射道效应，在近垒和垒上能区~(12)C + ~(237)Np和~(11)B + ~(238)U系统裂变碎片角分布可以用鞍点过渡态理论描述，没有发现异常；而对于~(16)O + ~(238)U系统裂变碎片角分布都有大于理论的异常，而且在垒上低能端异性度随能量的变化走向不同于以前测量的结果。虽然入射道效应证明了前平衡裂变的理论预言，但对于垒下能区，碎片异性度的异常依然存在，表明仅用前平衡裂变理论解释裂变碎片角分布的异常是不够的。为了澄清转移裂变对角分布异常的贡献，采用了角关联技术成功地区分出复合核裂变和转移裂变，实现了对纯复合核裂变碎片角分布各向异性的研究。在被研究的能区内，转移裂变占总裂变截面10%以下，而且它的各向异性度比复合核裂变的要小，扣除转移裂变的贡献使裂变碎片异性度提高5%，因此角分布异常不可能起源于转移裂变的贡献

Methanol synthesis from CO2 using a silicone rubber/ceramic composite membrane reactor

A one-dimensional isothermal pseudo-homogeneous parallel flow model was developed for the methanol synthesis from CO2 in a silicone rubber/ceramic composite membrane reactor. The fourth-order Runge-Kutta method was adopted to simulate the process behaviors in the membrane reactor. How those parameters affect the reaction behaviors in the membrane reactor, such as Damkohler number Da, pressure ratio p(r), reaction temperature T, membrane separation factor alpha, membrane permeation parameter phi , as well as the non-uniform parameter of membrane permeation L-1, were discussed in detail. Parts of the theoretical results were tested and verified; the experimental results showed that the conversion of the main reaction in the membrane reactor increased by 22% against traditional fixed bed reactor, and the optimal non-uniform parameter of membrane permeation rate, L-1.opt ,does exist. (C) 2003 Elsevier B.V All rights reserved.