Road Dust Loading and Chemical Composition at Major Cities in Fujian Province

采集并分析了福建省重点城市厦门、漳州、泉州和莆田城区具有代表性的57个地面扬尘和16个土壤样品的26种无机元素、8种水溶性离子和碳成分等组成.不同城市粒径≤100μM的路面尘负荷平均值在6.99 g.M-2与10.11 g.M-2之间,而粒径≤2.5μM的路面尘(PM2.5)负荷平均值在4.0 Mg.M-2和12.5 Mg.M-2之间.不同城市土壤尘和路面尘PM2.5中浓度最高的元素都是SI、CA、Al、fE和k,路面尘中CA元素明显富集,而主要人为来源的重金属元素如Cu、Pb、zn、Cr在路面尘PM2.5中的浓度显著高于土壤尘.漳州城区路面尘PM2.5中二次离子nH4+、nO3-和SO24-的含量明显高于其它地区,厦门、漳州和泉州城区路面尘PM2.5中Mg2+和CA2+之间都存在显著的正相关关系.四城市路面尘中有机碳(OC)的含量均高于济南、石家庄以及北京地面扬尘OC的含量,元素碳(EC)的含量均低于北京地区路面扬尘EC的含量.泉州和莆田两地OC和EC的相关性较好,说明路面尘中OC和EC有相同或相似的来源.质量平衡结果显示泉州和莆田路面尘PM2.5中含量最高的是土壤尘,其次为有机物.按化学组成特征对路面尘PM2.5进行聚类解析,得到受大气沉降影响、受土壤尘影响、受大气沉降和土壤尘共同作用以及受土壤尘和建筑尘共同作用4类样品.A total of 57 road dust and 16 urban soil samples were collected from four cities,Xiamen,Zhangzhou,Quanzhou and Putian in Fujian Province,China.Twenty-six elements,eight water soluble ions,organic carbon and elemental carbon in the fraction of particulate diameter less than 2.5 μm(PM2.5) derived through a suspension chamber were analyzed.The average loading of road dust with diameter less than 100 μm in the four cities ranged from 6.99 g·m-2 to 10.11 g·m-2,while the loading of PM2.5 ranged from 4.0 mg·m-2 to 12.5 mg·m-2.Both the soil and road dust samples were characterized with much higher concentrations of Si,Ca,Al,Fe and K.But for the anthropogenic elements such as Cu,Pb,Zn,Cr and Ti,much lower levels were found in the soil PM2.5 than those in the road dust PM2.5.Significantly higher levels of NH+4,NO-3 and SO2-4 were found in the road dust PM2.5 from Zhangzhou in comparison with those from other cities in this study.The calcium ion(Ca2+) content was significantly positively correlated with the Mg2+ content in the road dust PM2.5 from Xiamen,Zhangzhou and Quanzhou.The levels of organic carbon(OC) in the road dust PM2.5 in these four cities were higher than those reported in Ji'nan,Shijiazhuang and Beijing while the levels of elemental carbon(EC) were all lower than those in the urban road dust from Beijing,Significant positive correlation between EC and OC was found in samples from Quanzhou and Putian,suggesting the same and/or similar sources.The result of mass balance indicated that higher percentage compositions were soil and OM in both Quanzhou and Putian.Based on the cluster analysis,the 57 road dust samples were divided into four types: influenced by atmospheric deposition,influenced by soil dust,influenced by atmospheric deposition and soil dust,and influenced by soil and construction dust.国家自然科学基金项目(40971257;41171365); 环境保护公益性行业科研专项(201009004); 福建省自然科学基金计划项目(2009J05106

Uncertainty Analysis of Gas/Particle Partitioning of Atmospheric Polycyclic Aromatic Hydrocarbons

于2010年8月10~14日用双层石英膜和双层聚氨酯泡沫(Puf)的方法采集并分析了厦门大学海洋楼顶大气中气态和颗粒态多环芳烃(PAHS),并采用标准误差传递方法对气/粒分配系数(kP)的不确定度进行了分析.测量结果显示,低分子量PAHS如萘、苊、二氢苊和芴在Puf吸附体系中的穿透能力最强,穿透率接近50%;如考虑第一层石英滤膜对气态萘、苊和二氢苊的吸附影响,则校正后的kP值比校正前相应的kP值低1个数量级以上.采用标准误差传递方法得到PAHS气/粒分配系数kP的不确定度,介于28.14%~50.37%之间,且表现为易挥发和难挥发性PAHS的kP值皆具有较高的不确定度,而半挥发性PAHS的kP值的不确定度则较小.kP值的不确定度来源分析显示,气态PAHS浓度的不确定度的影响最大(方差贡献均值=77.9%),其次为颗粒态PAHS浓度的不确定度(方差贡献均值=22.0%),大气颗粒物浓度的不确定度影响最小(方差贡献均值=0.1%).因此,选择合适的采样系统以获取更加准确的气态PAHS的浓度,是提高PAHS气/粒分配系数准确度的关键.During the period from August 10,2010 through August 14,2010,particle and gas phase PAHs were collected and analyzed using double filters plus PUFs(Poly Urethane Foam) sampling system,and the uncertainties of gas/particle partitioning coefficients of PAHs were investigated using the propagation of errors formulas.The results showed that low-molecular weight PAHs such as naphthalene,acenaphthylene,acenaphthene and fluorene possessed the strong breakthrough capacity with the breakthrough rates close to 50% in double PUF cartridges.The corrected Kp values based on the sorption of PAHs to the primary filter were more than an order of magnitude higher than those without sorption correction for naphthalene,acenaphthylene and acenaphthene.The uncertainties for all the 19 PAHs ranged from 28.14% to 50.37% based on the standard error propagation formulas,with higher values for volatile and involatile PAHs and lower values for semi-volatile PAHs.The results also showed that the uncertainties of Kp were mainly contributed from the measurements of particle(average variance contribution was 77.9%) and gas(average variance contribution was 22.0%) phase PAHs while the contributions of total suspended particle were ignorable.Thus,getting more accurate data for gaseous PAHs using an appropriate sampling system is the key to increase the accuracy of gas/particle partitioning coefficients of PAHs.国家自然科学基金项目(40971257);环保公益性行业科研专项项目(201009004);国家海洋局近海海域生态环境重点实验室开放基金项目(200911

Screening of α-glucosidase Inhibitors in Active Constituents from Portulaca oleracea L.

[目的]观察马齿苋活性成分对兔小肠黏膜α-葡萄糖苷酶活性的影响,筛选α-葡萄糖苷酶抑制剂。[方法]提取分离马齿苋活性成分,在体外建立微量酶反应体系,PnPg作为底物,以阿卡波糖为参照,检测马齿苋活性成分对α-葡萄糖苷酶活性的影响。[结果]马齿苋总提取液、粗多糖和总生物碱对α-葡萄糖苷酶具有明显抑制作用,抑制效果接近于阿卡波糖,不饱和脂肪酸和总黄酮无抑制作用。[结论]马齿苋防治糖尿病的主要成分是生物碱和多糖,可能具有阿卡波糖样的降糖机制。[Objective] The research aimed to observe the effects of active constituents from Portulaca oleracea L.on α-glucosidase activity in intestine mucous to screen α-glucosidase inhibitors.[Method] The active constituents were extracted from Portulaca oleracea L..The trace enzyme reaction system was constructed in vitro.Taking the pNPG as substrate,and acarbose as control,the effects of the active constituents from Portulaca oleracea L.on α-glucosidase activity.[Result] Total extraction,alkaloids and polysaccharides from Portulaca oleracea L.could obviously inhibit α-glucosidase activity,but polyunsaturated fatty acid and flavonoids had no inhibition.[Conclusion] The main active constituents are alkaloids and polysaccharides from Portulaca oleracea L.for preventing diabetes,and the hypoglycemic mechanism is similar to acarbose.江西省教育厅科技项目(赣教技字〔2007〕285号);江西科技师范学院人才创新基金项目(2005

一维平推流反应器动态模型的新型求解方法

目前对一维平推流反应器动态模型求解时,常将反应体系中气体的体积流量假设为恒定参数。由于实际过程中气体的体积流量会随着温度等相关参数的改变而不断变化,该假设会对模拟结果带来一定的误差。本文针对此问题提出一种新的求解方法:首先通过有限差分法将动态模型中的空间和时间变量均离散化得到相应的代数方程组,再结合气体状态方程,推导出浓度关于气体摩尔流量和温度的函数,然后联立方程组进行求解;此方法有效克服了动态模拟中由于气体的体积流量变化而导致模型方程难以求解的困难。将所提出的方法应用于丙酮气相裂解生成乙烯酮过程的动态模拟,并将所得到的模拟结果与线上法动态模拟的结果进行比较,结果表明所提出的求解方法得到的模拟结果更加精确。国家自然科学基金面上项目（21576228

Relationship among negative affect,attachment and mindfulness in adults

目的:探讨成人负性情绪与依恋的关系及正念水平对其关系的调节作用。方法:招募&gt;18岁的成人514名,采用抑郁-焦虑-压力量表(DASS-21)、依恋经历量表(ECR)、正念注意觉知量表(MAAS)进行测量。采用一般模型分析、回归分析及简单斜率分析探讨调节作用。结果:DASS-21总分与依恋焦虑、依恋回避得分正相关(r=0.52、0.32,均P&lt;0.01),DASS-21总分及依恋焦虑、依恋回避得分均与MAAS得分负相关(r=-0.51、-0.49、-0.32,均P&lt;0.01)。调节效应检验结果表明,依恋焦虑得分、MAAS得分以及二者交互项均与DASS-21总分相关联(&beta;=0.35、-0.32、-0.11);依恋回避得分、MAAS得分以及二者交互项均均与DASS-21总分相关联(&beta;=0.18、-0.43、-0.08)。结论:成人的负性情绪与依恋的关系密切,正念水平在负性情绪与依恋之间有调节作用。</p

一步炭化磺化法制备煤基固体酸催化剂及其表征Preparation of coal based solid acid catalyst by one-step carbonization sulfonation and its characterization

以胜利褐煤为原料，通过浓硫酸一步炭化磺化法制备煤基固体酸催化剂，以油酸和甲醇的酯化反应评价催化剂的催化活性。采用单因素实验考察了固液比、磺化温度、磺化时间对催化活性的影响。采用红外光谱、元素分析、BET、SEM、XRD、热重分析等对煤基固体酸催化剂进行表征。结果表明，当磺化温度为110 ℃、磺化时间为90 min、固液比为1∶ 17时，煤基固体酸催化剂具有最优的催化活性，其催化油酸和甲醇的酯化反应的酯化率达到93.50%。煤基固体酸催化剂为具有较低石墨化程度的无定形碳结构，磺酸基已成功键合到了碳基载体上，同时具有丰富的含氧官能团，其表面呈现密集孔结构，且以介孔为主。煤基固体酸催化剂在低于140 ℃时具有较好的热稳定性，重复使用5次后，催化酯化率为57.21%。 Using Shengli lignite as raw material, coal based solid acid catalyst was prepared by one-step carbonization sulfonation of concentrated sulfuric acid. The catalytic activity of the catalyst was evaluated by esterification reaction of oleic acid and methanol.The effects of solid-liquid ratio, sulfonation temperature and sulfonation time on the catalytic activity were investigated.The coal based solid acid catalyst was characterized by IR, EA, BET, SEM, XRD and TG-DTG.The results showed that when the sulfonation temperature was 110 ℃, the sulfonation time was 90 min, and the solid-liquid ratio was 1∶ 17, the coal based solid acid catalyst had the best catalytic activity with the esterification rate reaching 93.50%.The catalyst was amorphous carbon structure with low graphitization degree. The sulfonic acid group was successfully bonded to the carbon-based support. The catalyst had abundant oxygen-containing functional groups, and its surface presented dense pore structure, which was mainly mesoporous. The catalyst had better thermal stability below 140 ℃. After repeated use for 5 times, the esterification rate was 57.21%