可见光下氮掺杂罗丹明B分子印迹TiO_2的选择性光催化性能

采用溶胶-凝胶法和分子印迹技术,以尿素为氮源、罗丹明B为模板分子制备了氮掺杂罗丹明B分子印迹TiO_2粉末(N-TiO_2-RhB),并对样品进行了XRD、UV-Vis DRS和BET表征。表征结果显示:氮掺杂和分子印迹一定程度改善了样品的孔隙结构和孔径分布,N-TiO_2-RhB的比表面积和孔体积分别为TiO_2的1.9倍和1.5倍;氮掺杂使TiO_2的光吸收带边发生红移,而分子印迹不能改变催化剂的光吸收带边。N-TiO_2-RhB具有最佳的可见光活性和选择性,对罗丹明B的降解率高达92.7%。对罗丹明B、罗丹明6G、甲基紫和甲基绿的降解过程均符合一级反应动力学方程。     

Distal impacts of aquarium trade: Exploring the emerging sandhopper (<Emphasis Type="Italic">Orchestoidea tuberculata</Emphasis>) artisanal shore gathering fishery in Chile

Artisanal fishery activities support the livelihoods of millions of people worldwide, particularly in developing countries. Within these fisheries, distal global drivers can promote switching between alternative target resources. These drivers can promote the rapid development of new, unregulated and previously unexploited fisheries that pose a threat to the sustainability of ecosystems. In this paper, we describe a new artisanal shore gathering activity that targets a previously unexploited resource: the sandhopper (Orchestoidea tuberculata). The activity is driven by aquarium trade demand for food. We used mixed methods to describe the activity, assessed basic socio-economic incentives, and estimated Catches per Unit Effort. Results show that the sandhopper plays an important role for the livelihoods of shore gatherers engaged in the activity. Gatherers have adapted and developed two main extraction methods with different degrees of investment and extraction rates. Furthermore, gatherers have developed local knowledge regarding the ecology and management of the resource. Results show that economic incentives can motivate a rapid expansion of this unregulated activity. Future research gaps and management options to address the development of this fishery are discussed in light of these findings.     

Achieving biodiversity benefits with offsets: Research gaps,challenges, and needs

Biodiversity offsets are becoming increasingly common across a portfolio of settings: national policy, voluntary programs, international lending, and corporate business structures. Given the diversity of ecological, political, and socio-economic systems where offsets may be applied, place-based information is likely to be most useful in designing and implementing offset programs, along with guiding principles that assure best practice. We reviewed the research on biodiversity offsets to explore gaps and needs. While the peer-reviewed literature on offsets is growing rapidly, it is heavily dominated by ecological theory, wetland ecosystems, and U.S.-based research. Given that majority of offset policies and programs are occurring in middle- and low-income countries, the research gaps we identified present a number of risks. They also present an opportunity to create regionally based learning platforms focused on pilot projects and institutional capacity building. Scientific research should diversify, both topically and geographically, in order to support the successful design, implementation, and monitoring of biodiversity offset programs.     

Genotoxicity assessment of human peripheral Lymphocytes induced by thallium(I) and thallium(III)

Thallium is a non-essential metal with a wide range of industrial uses. However, thallium is also a potential pollutant with high potential toxicity to humans. In the present study, we analyzed and compared the cellular and genotoxic effects of thallium in two main oxidation states by applying chromosome aberration assays to human peripheral lymphocytes. We observed that thallium(I) sulfate reduced the mitotic index at all tested concentrations (0.5, 1, 5, 50 and 100 μg/mL), whereas thallium(III) chloride was toxic at concentrations ≥1 μg/mL. Thallium(I) and thallium(III) treatment significantly increased structural chromosomal aberrations, with and without gaps, and increased the percentage of aberrant cells without gaps. Furthermore, satellite associations and numerical chromosomal aberration tests showed significant differences at a few of the tested concentrations. The satellite association test is related to aneuploidy. Thallium salts increased satellite associations when hyperploid cells were observed. Our results indicated that the two oxidation states of thallium induced toxicity in vitro – i.e. cyto/genotoxic (clastogenic and aneuploidogenic) effects.     

有机磷及氨基甲酸酯类农药单独和联合作用对PC_(12)细胞DNA损伤的影响

研究有机磷类农药毒死蜱和对硫磷、氨基甲酸酯类农药克百威和残杀威单独及联合染毒大鼠嗜铬细胞瘤株(PC12细胞)所致的DNA损伤情况及联合作用模式。分别以0μmol·L~(-1)、50μmol·L~(-1)、100μmol·L~(-1)、200μmol·L~(-1)、400μmol·L~(-1)的有机磷农药毒死蜱、对硫磷与0μmol·L~(-1)、25μmol·L~(-1)、50μmol·L~(-1)、100μmol·L~(-1)、200μmol·L~(-1)的氨基甲酸酯类农药克百威、残杀威单独及两两联合染毒PC12细胞12 h后进行彗星实验,采用彗尾长度、尾部DNA百分含量、尾矩3个指标来衡量DNA损伤程度。结果表明:毒死蜱、克百威、对硫磷、残杀威染毒PC12细胞12 h后,细胞出现拖尾,呈现典型的彗星图像。染毒后PC12细胞彗尾长度、尾部DNA百分含量、尾矩较对照组显著增加,差异有统计学意义(P0.01)。析因分析表明,无论低剂量联合还是高剂量联合,毒死蜱与克百威、对硫磷与残杀威均有交互作用(P0.01),作用模式为协同作用。以上结果提示,有机磷及氨基甲酸酯类农药单独及联合作用均可引起PC12细胞DNA损伤,联合作用后损伤程度要高于单独作用,且低剂量和高剂量联合时均存在交互作用,作用模式为协同作用。     

Are children playgrounds safe play areas? Inorganic analysis and lead isotope ratios for contamination assessment in recreational (Brazilian) parks

Environmental Science and Pollution Research - In city playgrounds, there is a potential risk of harming children’s health by contamination coming from anthropogenic activities. With the aim...     

Tissue distribution, isozyme abundance and sensitivity to chlorpyrifos-oxon of carboxylesterases in the earthworm Lumbricus terrestris

A laboratory-based study was conducted to determine the basal carboxylesterase (CbE) activity in different tissues of the earthworm Lumbricus terrestris, and its sensitivity to the organophosphate (OP) pesticide chlorpyrifos-oxon (CPx). Carboxylesterase activity was found in the pharynx, crop, gizzard, anterior intestine, wall muscle and reproductive tissues of L. terrestris, and multiple tissue-specific isozymes were observed by native gel electrophoresis. Esterase activity and sensitivity to CPx inhibition varied on a tissue- and substrate-specific basis, suggesting isoforms-specific selectivity to OP-mediated inhibition. Three practical issues are recommended for the use of earthworm CbE activity as a biomarker of pesticide exposure: (i) CbE should be measured using several routine substrates, (ii) it should be determined in selected tissues instead of whole organism homogenate, and (iii) earthworm CbE activity should be used in conjuncture with other common biomarkers (e.g., ChE) within a multibiomarker approach to assess field exposure of OPs, and potentially other agrochemicals.     

单液滴微萃取—气相色谱/质谱法检测水中多环芳烃

采用单液滴微萃取-气相色谱/质谱(GC/MS)法建立了检测水中多环芳烃(PAHs)的方法,研究了萃取溶剂种类、萃取时间、搅拌速度对萃取效率的影响,确定了最佳单液滴微萃取条件,该法用于水中PAHs的检测,16种PAHs的线性范围为0.2～7.0μg/mL,相关系数≥0.9784,检出限为0.002～0.190μg/mL,相对标准偏差为7.1%～15.1%,加标回收率在81%～122%.     

生活垃圾卫生填埋场甲烷减排与控制技术研究

系统地研究了生物氧化、生物抑制和风力驱动准好氧填埋的生活垃圾卫生填埋场甲烷减排集成技术.研究表明,喷洒了NMS营养液(80 mL/kg)的矿化垃圾为甲烷氧化覆盖层,可以持续氧化甲烷,第23天后甲烷氧化率稳定在75%左右;当氯仿质量浓度为20 mg/kg或乙炔体积分数达到1.2%时,甲烷产量极少,产甲烷菌几乎被完全抑制;采用风帽技术的改进型准好氧填埋可以利用风速0.5 m/s的自然风,在不增加成本的前提下大幅减少甲烷排放.     

张家界体验旅游产品设计与开发

随着体验经济时代的到来,旅游消费者消费理念日趋成熟,人们寻求个性化的服务,追求灵活性、冒险性与多样性,追求真实与差异,对旅游产品提出了更高的要求.在分析张家界旅游产品现状的基础上,提出开发体验旅游产品的设想以及整体设计方案,并从加强体验意识、明确市场定位等方面提出全面开发体验旅游产品的具体建议.