238U、239Pu在板岩和土壤中迁移速度的实验模拟

以西南某低放废物处置库地质环境中板岩和土壤介质为研究对象,开展了238U和239Pu核素在这两种地质介质中的动态迁移实验研究,通过氚穿透实验(地下水流速=1 mL.min-1、实验柱连续淋洗时间=180 d)得到氚在板岩中的弥散系数DL为0.027 cm2.min-1,弥散度αL为0.324 cm,在土壤中的弥散系数DL为0.064 cm.2min-1,弥散度αL为0.895 cm.通过淋滤实验(地下水流速=0.1 mL.h-1、实验柱连续淋洗时间=350 min),得到了238U在板岩和土壤介质中的迁移速度分别为6.1—8.1 cm.a-1和7.3—8.5 cm.a-1,239Pu在板岩和土壤介质中的迁移速度分别为4.1—6.1 cm.a-1和3.7—4.9 cm.a-1.     

卡瓦胡椒素B对人非小细胞肺癌A549细胞的抑制作用

卡瓦胡椒素B是药用植物卡瓦胡椒根中的一种天然查耳酮类化合物,研究了其对人非小细胞肺癌A549细胞的增殖抑制作用及其诱导细胞凋亡的分子机制.实验结果显示,卡瓦胡椒素B能显著抑制非小细胞肺癌A549细胞的增殖,且随着药物浓度的增加、处理时间的延长其抑制作用呈明显的剂量时间效应;同时,卡瓦胡椒素B能显著诱导A549细胞凋亡、细胞周期阻滞于G2-M期;分子机制研究表明,卡瓦胡椒素B能通过活化JNK激酶活性、下调凋亡抑制蛋白survivin的表达以及激活PARP活性从而导致其对A549细胞的增殖抑制作用.结果表明卡瓦胡椒素B对人非小细胞肺癌的预防与治疗可能具有潜在价值.     

Selenium and hazardous elements distribution in plant–soil–water system and human health risk assessment of Lower Cambrian,Southern Shaanxi,China

The natural selenium poisoning due to toxic Se levels in food chain had been observed in humans and animals in Lower Cambrian outcrop areas in Southern Shaanxi, China. To find out the distribution pattern of selenium and other hazardous elements in the plant, soil and water of Lower Cambrian in Southern Shaanxi, China, and their possible potential health risk, a total of 30 elements were analyzed and the health risk assessment of 18 elements was calculated. Results showed that the soil, plant and natural water of Lower Cambrian all had relatively high Se levels. In Lower Cambrian, the soil was enriched with Se, As, Ba, Cu, Mo, Ni, Zn, Ga, Cd and Cr (1.68 < I_geo < 4.48, I_geo; geo-accumulation index). In same plants, the contents of Se, Cd and Zn (except Cd in corn and rice, Zn in potato and corn) of Lower Cambrian were higher than that of the other strata. Ba and Ga in natural water were higher than that of the other strata, while K and Cs were opposite. The health risk assessment results showed that the people living in outcrop areas of Lower Cambrian had both high total non-carcinogenic risk of 18 elements (HI = 16.12, acceptable range: < 1) and carcinogenic risk of As (3.98E−04, acceptable range: 10⁻⁶–10⁻⁴). High contents of Se, As, Mo and Tl of Lower Cambrian may pose a health risk to local people, and food intake was the major pathway. For minimizing potential health risk, the local inhabitants should use the mix-imported food with local growing foods.

     

How aerosol direct effects influence the source contributions to PM2.5 concentrations over Southern Hebei,China in severe winter haze episodes

The aerosol direct effects result in a 3%–9% increase in PM_2.5 concentrations over Southern Hebei. These impacts are substantially different under different PM_2.5 loadings. Industrial and domestic contributions will be underestimated if ignoring the feedbacks. Beijing-Tianjin-Hebei area is the most air polluted region in China and the three neighborhood southern Hebei cities, Shijiazhuang, Xingtai, and Handan, are listed in the top ten polluted cities with severe PM_2.5 pollution. The objective of this paper is to evaluate the impacts of aerosol direct effects on air quality over the southern Hebei cities, as well as the impacts when considering those effects on source apportionment using three dimensional air quality models. The WRF/Chem model was applied over the East Asia and northern China at 36 and 12 km horizontal grid resolutions, respectively, for the period of January 2013, with two sets of simulations with or without aerosol-meteorology feedbacks. The source contributions of power plants, industrial, domestic, transportation, and agriculture are evaluated using the Brute-Force Method (BFM) under the two simulation configurations. Our results indicate that, although the increases in PM_2.5 concentrations due to those effects over the three southern Hebei cities are only 3%–9% on montly average, they are much more significant under high PM_2.5 loadings (~50 μg·m⁻³ when PM_2.5 concentrations are higher than 400 μg m⁻³). When considering the aerosol feedbacks, the contributions of industrial and domestic sources assessed using the BFM will obviously increase (e.g., from 30%–34% to 32%–37% for industrial), especially under high PM_2.5 loadings (e.g., from 36%–44% to 43%–47% for domestic when PM_2.5>400 μg·m⁻³). Our results imply that the aerosol direct effects should not be ignored during severe pollution episodes, especially in short-term source apportionment using the BFM.     

厌氧折流板式微生物燃料电池堆影响因素研究

微生物燃料电池(MFC)中输出电压/电流的提升,以及反应器体积的扩展放大是其工程化应用的关键。本文构建了一个总体积为6.4 L的新型厌氧折流板式微生物燃料电池堆(ABSMFC)。以葡萄糖作为底物,探讨了阳极材料、液面高程差和水力停留时间(HRT)等因素对ABSMFC性能的影响。结果表明,碳纤维毡作为阳极时,电池单体外电路平均分压(R_(ex)=1 000Ω)为210 mV,填充石墨颗粒后增加到319.8 mV。格室间存在液面高程差时,电池单体、串联和并联的功率密度分别为207.1、181.1和215.7 mW/m~2,当无液面高程差(即水力相连)时为205.8、69.5和151.5 mW/m~2。4个电池单体串联和并联连接时,HRT对ABSMFC的产电稳定性无影响,溶解性COD的去除率和库仑效率均随HRT的增加而升高,且并联效果优于串联。     

污泥水解蛋白液对食用菌生长的影响研究

将污泥(食品工厂污泥)经过酸碱水解制备水解蛋白液(肽类和氨基酸复合物,属于微生物蛋白)、并与豆粕(植物蛋白)、屠宰厂动物羽毛(动物蛋白)水解蛋白液、以及常规食用菌氮源麸皮、大米制糖厂米渣作为平菇栽培氮源或营养添加剂,测试对平菇的菌丝生长、产量和生物转化率的影响。结果表明,几种水解蛋白液对平菇的菌丝生长、产量、生物转化率影响明显,污泥水解蛋白液对菌丝的生长效果最好,其余2种水解蛋白液也有促进作用。添加污泥水解蛋白液最高产量可达806 g/袋,添加豆粕水解蛋白液的最高产量为532 g/袋,添加屠宰厂动物羽毛水解蛋白液的产最高量为525 g/袋;对照为480 g/袋(常规棉籽壳)。生物转化率分别为161.2%、106.4%和105.0%,而对照生物转化率为96%;增产率分别为67.92%、10.83%和9.38%。因此,污泥、豆粕、屠宰厂动物羽毛蛋白水解液可提高平菇产量,该研究也为污泥资源化利用建立了基础。     

固体厌氧消化原料流变特性研究综述

厌氧消化原料的流变特性是厌氧消化工艺设计和运行的重要参数。本文从研究对象、实验操作、研究内容和结果、影响因素以及发展方向等方面对固体厌氧消化原料,特别是污泥的流变特性研究现状进行了概述。研究表明,污泥来源广泛,成分复杂,属于非牛顿流体的范畴,其流变特性受多种因素影响,其中污泥的总悬浮固体(TSS)(或混合液悬浮固体(MLSS))和温度是最主要的影响因素。大部分研究采用层流剪切实验对物料的流变特性进行表征,研究对象范围有待于扩大。尚需针对流体本构方程的改进,共消化对于原料流变特性的影响,混合液固、液相指标与流变参数的关系等方面开展研究,为利用流变参数作为工艺控制参数提供理论依据,并解决工程放大等问题。     

基于资源禀赋特征的怒江流域高山峡谷区经济发展策略思考

怒江流域高山峡谷区域具有集边疆、山区、民族、贫困为一体的特征,是我国典型的欠发达地区.尽管目前怒江流域已经进入工业化初期的经济发展阶段,但是长期闭塞、贫困和工业基础薄弱使流域经济发展动力不足.怒江流域的发展要把握云南建设面向东南亚、南亚开放的重要桥头堡这一战略机遇,立足自身的资源优势,引进外界资本与技术,打造水能资源经济,培育生态服务产业,同时通过交通基础设施建设和人力资本的培育改善发展环境.     

苯并芘和邻苯二甲酸二(2-乙基己基)酯复合暴露对稀有鮈鲫的内分泌干扰效应研究

为评价典型有机污染物共存情况下对长江上游三峡库区特有珍稀鱼类的环境风险,以稀有鮈鲫(Gobiocypris rarus)为对象,研究了多环芳烃和酞酸酯的代表物苯并芘(BaP)和邻苯二甲酸二(2-乙基己基)酯(DEHP)单独及复合暴露而引起的内分泌干扰效应。将成年稀有鮈鲫暴露于不同浓度的BaP(0.1、1μg·L~(-1))、DEHP(10、100μg·L~(-1))和BaP+DEHP((0.1+10)、(1+100)μg·L~(-1))中28 d后,测定了体质系数、性激素含量、下丘脑-垂体-性腺(HPG)轴和肝脏中与生殖相关基因的表达。结果表明:在雌鱼中,单独BaP或DEHP暴露对鱼体性激素含量、基因表达量无显著影响; BaP和DEHP复合暴露时,高浓度组睾酮(T)含量升高但雌二醇(E2)含量下降,fsh、vtg、 cyp17和17β-hsd基因表达量上调,cyp19a则下调,表现出协同毒性。因而雌鱼中性激素水平的改变可能与类固醇合成相关基因表达量的改变有关。而无论在单独暴露或是复合暴露情况下,对雄鱼体内性激素无显著影响。以上检测到的激素或基因表达量的改变主要发生在高剂量的复合暴露组中,而长江上游三峡库区水体中多环芳烃和酞酸酯含量低于暴露的最低浓度,因此推测,库区存在的多环芳烃和酞酸酯同时作用时不会对三峡库区上游水体中的鱼类产生生殖内分泌干扰效应。     

Incidence of polybrominated diphenyl ethers in central air conditioner filter dust from a new office building

This study examined polybrominated diphenyl ethers (PBDEs) in central air conditioner filter (CACF) dust from a new office building in Shenzhen, China. Human exposure to PBDE via dust inhalation and ingestion were also estimated. PBDEs level in CACF dust was lower than those in the other countries and regions. Approximately 0.671 pg/kg bw/day PM_2.5 (Particulate Matter up to 2.5 μm in size) bounded Σ₁₅PBDEs can be inhaled deep into the lungs and 4.123 pg/kg bw/day PM₁₀ (Particulate Matter up to 10 μm in size) bounded Σ₁₅PBDEs tend to be deposited in the upper parts of the respiratory system. The average total intake of Σ₁₅PBDEs via dust inhalation and ingestion for adults reached ∼141 pg/kg bw/day in this building. This value was far below the reference dose (RfD) recommended by United States Environmental Protection Agency. Human exposure to PBDEs via dust inhalation and ingestion in the new building is less than the old ones.