Study on Existent Form of Mercury in Sediments of Miyun Reservoir,Beijng

在改进Tessier方法的基础上,利用冷原子吸收对北京密云水库沉积物中汞的形态进行研究,发现密云水库沉积物的总汞含量较高,沉积物中的汞主要以气态汞、有机汞和硫化物汞的形式存在,生物可以直接利用的汞较低,但一些目前不能直接利用的汞在一定条件下可以转化为可利用的汞,需要对此加以关注。On the bases of modified Tessier method,the existent forms of mercury in sediments of Miyun reservoir,Beijing were determined with cold vapor atomic absorption(CVAA).The results showed that total mercury in the sediments is high,and that gaseous mercury,organic mercury and sulfide mercury(residual mercury) are the main form of mercury.Most of them can not be used by biomass,but,what should be noted is that some unusable mercury can be transformed usable mercury under special conditions..国家自然科学基金(20077016);; 中国博士后基金(2002032148);; 厦门大学行动计划联合资助项

Pollution and Assessment of Heavy Metals in Huangpu River Sediments

采用地积累指数法和潜在生态危害指数法对黄浦江沉积物中的重金属进行了评价研究,解释了两种评价方法结果存在差异的原因。两种评价方法的结果均表明,黄浦江砷污染严重,镉中等程度污染,且各个江段均受到了一定程度的污染。Based on the principle of sedimentology and environmental behavior of heavy metals, the index of geoaccumulation and potential ecological risk index were used to evaluate heavy metals pollution in sediments of Huangpu River, Shanghai. The difference between these two methods was explained as well. Results showed that each section of the River has been polluted with As and Cd as the major heavy metal pollution.国家自然科学基金委员会(20077016);; 中国博士后基金(2002032148);; 厦门大学行动计划(0660-X01114

微通道反应器中催化裂解合成nn二甲基丙烯酰胺新工艺研究

N，N-二甲基丙烯酰胺（DMAA）是一种具有广泛开发应用前景的精细化工原料，在石油开采、纤维塑料改性、精细化工、生命科学等领域有广阔应用前景。研究了微通道反应器中以3-（N,N-二甲氨基）-N，N-二甲基丙酰胺（DMDA）为原料、四丁基溴化铵（TBAB）为催化剂合成DMAA的催化裂解新工艺。考察了催化剂用量、体积流速、反应温度对DMDA单程转化率的影响。优化选择了较优工艺参数组合：催化剂用量m（TBAB）：m（DMDA）为0.02，体积流速0．24mL·min^-1，反应温度270℃，DMDA单程转化率达17．0％，时空转化率（STC）达2．36×10^9mol·m^-3·h^-1。微通道反应器中时空收率是常规反应器的1500倍

壳寡糖对猪蓝耳病灭活疫苗的佐剂活性研究

目的研究探讨不同聚合度、不同脱乙酰度的壳寡糖对猪蓝耳病灭活疫苗(PRRSV)的免疫佐剂活性。方法不同聚合度和脱乙酰度的壳寡糖COS(聚合度2-8,脱乙酰度>95%)、COSNAC(聚合度2-8,乙酰度>90%)、HCOS(聚合度2-20,脱乙酰度>95%)、50%COS(聚合度2-8,脱乙酰度≈50%)、生理盐水和油乳佐剂ISA206分别与PRRSV灭活疫苗配伍,以肌肉注射的方式免疫BalB/C小鼠,以单独注射生理盐水的小鼠作为空白对照组,初次免疫四周后进行加强免疫,加强免疫四周后进行再次加强免疫,每次免疫两周后ELISA法检测小鼠血清中PRRSV特异性N蛋白抗体的滴度及亚型、亚类;再次加强免疫两周后MTT法测定免疫小鼠脾脏淋巴细胞增殖反应,流式细胞术测定免疫小鼠脾脏淋巴细胞CD4~+、CD8~+、CD3~+和CD19~+细胞亚群的比例,中性红比色法检测免疫小鼠腹腔巨噬细胞的吞噬功能。结果再次加强免疫后,寡糖COSNAC可显著增强小鼠血清中PRRSV抗体的滴度,其增强作用弱于阳性对照组;COSNAC可显著提高免疫小鼠血清中IgGl、IgG2a、IgG2b抗体的含量;COSNAC组、50%COS组IgG2b亚类抗体与PRRSV组相当,其中以COSNAC组IgG2b抗体产生的水平最高,但不及ISA206组。COSNAC组、50%COS组IgM亚类抗体显著高于PRRSV组;MTT法的结果表明,与抗原对照组和阳性对照组相比较,HCOS能明显增强免疫小鼠脾脏T淋巴细胞和B淋巴细胞的增殖反应,并且HCOS促进B淋巴细胞增殖的作用明显强于ISA206组;经流式细胞术测定,寡糖COS、HCOS、COSNAC均可显著提高免疫小鼠脾脏淋巴细胞CD4~+T细胞和CD8~+T细胞的比例,寡糖COS、HCOS、COSNAC均可显著提高CD3~+细胞的含量及CD3~+/CD19~+细胞的比值,此外50%COS可显著提高CD19~+细胞的比值,并且显著降低CD3~+/CD19~+细胞的比值;经中性红比色法测定,与ISA206组相比较,COSNAC免疫后小鼠腹腔巨噬细胞的吞噬功能显著提高,该作用经LPS和PRRSV抗原诱导后明显增强。结论壳寡糖可增强小鼠对PRRSV灭活疫苗的免疫应答,是一种新型的免疫佐剂,可用于猪蓝耳病等灭活疫苗的开发中

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies