Antibacterial behavior of silver-modified clinoptilolite-heulandite rich tuff on coliform microorganisms from wastewater in a column system

The water disinfecting behavior of silver-modified clinoptilolite–heulandite rich tuff (ZSAg) as an antibacterial agent against coliform microorganisms from water in a continuous mode was investigated. Silver recovery from the disinfected effluents by the sodium-modified clinoptilolite–heulandite rich tuff (ZSNa) was also considered. Escherichia coli (ATCC 8739) and total coliform microorganisms, as indicators of microbiological contamination of water, were chosen to achieve the disinfection of synthetic wastewater or municipal wastewater. Ammonium (NH₄⁺) and chloride (Cl⁻) ions were added to the synthetic wastewater as an interfering chemical species on the disinfection processes. The antibacterial activity of the ZSAg as a bactericide was measured by the coliform concentration as evaluated by the APHA method. The amount of silver in the disinfected effluents was determined using atomic absorption spectroscopy. The inactivation of the ZSAg was calculated from the breakthrough curves based on the model reported by Gupta et al. It was found that when the silver concentration in the effluent is less than 0.6 μg/mL, the bacterial survival percentage increased and the volume of disinfected water diminished. The total silver amounts found in the effluent at the end of the disinfection processes varied depending on the water treated (synthetic or municipal wastewater). The presence of NH₄⁺ ions in synthetic wastewater influent notably improved the disinfected water volume (zero NVC/100 mL), in comparison to the disinfection of the same influent without NH₄⁺ ions. A contrary water disinfection behavior was observed in the presence of Cl⁻ ions. The silver recovery does not depend on the mass of the sodium zeolitic bed according with the wastewater to be treated (synthetic or municipal wastewater) and the presence of NH₄⁺ or Cl⁻ ions in the influent also influenced the silver recovery from wastewater. The ZSNa did not have antibacterial activity. Therefore the amount of bactericide agent (silver-modified natural zeolite), coliform microorganisms from water (E. coli or consort of coliform microorganisms) as well as the water quality (synthetic wastewater or municipal wastewater) influenced both the disinfection process and the silver recovery in a column system.     

An environmental perspective of the post-tsunami scenario along the coast of Tamil Nadu, India: role of sand dunes and forests

An endeavor to feel the pulse of a coast devastated by a powerful oceanographic event is made. Results of field investigations along Tamil Nadu seaside revealed that the tsunami of December 2004 demolished dwellings within strips ranging from 6 to 132m (average width, 41m) from the dune, and flooded up to 862m (average, 247m) from the shore. The event damaged sand dunes, ripped dune vegetation, created new water bodies and shattered high value assets. Comparatively, casuarina forests performed remarkably. Uprooting of trees was exclusively restricted to a frontal strip ranging from 5 to 25m (average width, 14m) nearest to the shore where the maximum wave run-up was 6.5m above sea level. Sand dunes in general, and casuarina forests in particular, posses an innate capacity to dissipate powerful waves. This inference is supported by (a) negligible over wash along belts characterized by high dune complexes, (b) intact villages shielded by dense forests as well as sand dunes, and (c) maximum destruction of open beach front influenced by intense human activity. In this context, the coastal regulation zone (CRZ) Notification of 1991 offers sufficient scientific validity to be endorsed. However, post-tsunami ecosystem management initiatives lack a scientific basis. Therefore, a coastal hazards policy, that considers adaptation, dune restoration and forested buffer zones, is a sustainable long-term option for Indian coasts.     

A “measurable” definition of sustainable development based on closed cycles of resources and its application to energy systems

Human society consumes resources that it is not able to reproduce. Human activities are still based on “open cycles,” starting from a condition of natural environmental balance and reaching an environmental imbalance. The challenging scope of scientific and technological research towards sustainability appears clear if it is based on this analysis: to find development systems based on “closed cycles” of resources. The challenging objective of realizing closed cycles leads to a definition of sustainability that indicates the path to sustainable development, as well as stating the general principle. It also provides a key to the qualitative measurement of sustainability. This means that the sustainability level of a system can be measured by measuring its capacity to avoid the consumption of resources. Zero consumption is a necessary condition for sustainability, and brings about as a side effect the highly desired “zero-waste” result. Materials entering the proposed endless scheme pass through the process of usefulness without losing their capacity to feed the system again after being used. Thus, the concept of “consumption” itself is replaced by one of “use” when resources are inserted into closed loops capable of feeding human development. The application of the closed cycle sustainability criterion particularly displays its feasibility, and a theoretical guiding role, in the energy sector. Energy vectors such as hydrogen and electricity enable the closure of the energy resources loop by effectively approaching the objective of “zero consumption” (and the side result of “zero waste”) through already demonstrated technological solutions.     

Assessment of the Enabling Rural Innovation (ERI) approach: Case studies from Malawi and Uganda

This paper presents lessons from applying an innovative action research approach for linking smallholder farmers to markets, in eastern and southern Africa. The Enabling Rural Innovation (ERI) approach aims to strengthen social organization and entrepreneurial capacity in rural communities. It focuses on fostering community‐based capacity for the inclusion of rural women and the poor in analyzing and accessing market opportunities. Using case studies from Malawi and Uganda the paper assesses the outcomes of ERI on rural communities with a focus on human capital, gender issues and investment in natural resource management. Results show that households are benefiting significantly from linkages to markets in terms of increasing household incomes, and accumulating assets. Skills in analyzing markets and in negotiating with traders have increased among smallholder farmers. The integration of gender in the approach has led to changes in gender decision making patterns at household and community level towards a more shared decision‐making process. The results however show a difference in skills between men and women, with women showing lower levels of skills acquisition. Farmer participatory research has increased investments in improved technologies such as fertilizer applications for soil fertility management.     

Mapping social vulnerability to natural hazards in Italy: A suitable tool for risk mitigation strategies

Italy is one of the European countries that are most heavily exposed to a wide range of natural hazards, which might cause large economic losses. In this context, the assessment of social vulnerability has an important role for evaluating the capacity of a community to prepare for, respond to and recover from disasters. However there are currently no published studies analysing social vulnerability and its spatial distribution in Italy. Within this framework, this paper aims to apply a proven method for assessing social vulnerability at the national scale, while considering the contribution of the socioeconomic and demographic factors that affect the Italian population. The proposed methodology is based on the Hazard-of-Place Model approach, and uses free and open source software applications (FOSS). Specifically, we selected significant components through Principal Component Analysis and derived their spatial distribution. Using component scores, we derived a social vulnerability index, evaluated its geographic distribution, and performed a cluster analysis on its spatial variation. The analysis identified different spatial patterns across Italy, providing useful information for identifying the communities most likely to experience negative natural disaster impacts due to their socioeconomic and demographic characteristics. This research represents an important contribution to improve the potentiality of risk mitigation strategies and in designing risk custom-made policies.     

超高“Z型”中庭高度对自燃排烟特性影响的数值模拟研究

超过12m的超高中庭发生火灾时,常规排烟方法不能完全满足实际需求。通过FDS软件对某超高"Z型"中庭进行数值模拟,研究中庭高度对自然排烟特性的影响。该"Z型"中庭底层南面是自然进风口,顶层北面是自然排烟口,以烟气最先到达指定楼层人员危险时间值为到达危险时间。实验条件下模拟结果表明:无风情况下,中庭高度增加,到达危险时间增加,自然排烟效果增强。到达危险时间t与中庭高度h之间满足一定指数增长关系:t=y0+Aexp(h/α),中庭火源位置和中庭宽度对y0、A和α有一定影响。有风情况下,外界风向与进风口方向一致时,中庭自然排烟效果优于无风状况,中庭越高效果越强。在外界风向与排烟口方向相反时,烟气倒灌进中庭,自然排烟效果较弱。     

黄河三角洲自然保护区秋冬季水鸟群落组成与生境关系分析

于2014年10月至2015年1月采用样线调查法对黄河三角洲自然保护区秋季迁徙期和越冬期水鸟群落结构进行调查研究,调查共包括8条样线40个观测点.结果表明:(1)秋季迁徙期共记录水鸟6目14科54种,国家Ⅰ级保护鸟类5种,国家Ⅱ级保护鸟类8种;越冬期共记录水鸟5目7科31种,国家Ⅰ级保护鸟类1种,国家Ⅱ级保护鸟类4种.(2)2个时期雁形目水鸟种类和数量均占优势,豆雁(Anser fabalis)、斑嘴鸭(Anas poecilorhycha)、赤膀鸭(Anas strepera)和绿头鸭(Anas platyrhynchos)为优势物种,丹顶鹤(Grus japonensis)、东方白鹳(Ciconia boyciana)和大大鹅(Cygnus cygnus)等珍稀水鸟也有一定的种群数量.(3)秋季迁徙期水鸟种数、数量和ShannonWiener多样性指数多于或高于越冬期.(4)5种典型生境之间水鸟种类和数量存在差异,天然水域是水鸟群落的主要分布区.(5)自然生境内的水鸟种数、数量和Shannon-Wiener多样性指数一般多于或高于人工生境.相似性分析结果表明,自然生境之间水鸟群落结构相似程度高于人工生境.     

An integrated EDIB model for probabilistic risk analysis of natural gas pipeline leakage accidents

Natural gas pipeline construction is developing rapidly worldwide to meet the needs of international and domestic energy transportation. Meanwhile, leakage accidents occur to natural gas pipelines frequently due to mechanical failure, personal operation errors, etc., and induce huge economic property loss, environmental damages, and even casualties. However, few models have been developed to describe the evolution process of natural gas pipeline leakage accidents (NGPLA) and assess their corresponding consequences and influencing factors quantitatively. Therefore, this study aims to propose a comprehensive risk analysis model, named EDIB (ET-DEMATEL-ISM-BN) model, which can be employed to analyze the accident evolution process of NGPLA and conduct probabilistic risk assessments of NGPLA with the consideration of multiple influencing factors. In the proposed integrated model, event tree analysis (ET) is employed to analyze the evolution process of NGPLA before the influencing factors of accident evolution can be identified with the help of accident reports. Then, the combination of DEMATEL (Decision-making Trial and Evaluation Laboratory) and ISM (Interpretative Structural Modeling) is used to determine the relationship among accident evolution events of NGPLA and obtain a hierarchical network, which can be employed to support the construction of a Bayesian network (BN) model. The prior conditional probabilities of the BN model were determined based on the data analysis of 773 accident reports or expert judgment with the help of the Dempster-Shafer evidence theory. Finally, the developed BN model was used to conduct accident evolution scenario analysis and influencing factor sensitivity analysis with respect to secondary accidents (fire, vapor cloud explosion, and asphyxia or poisoning). The results show that ignition is the most critical influencing factor leading to secondary accidents. The occurrence time and occurrence location of NGPLA mainly affect the efficiency of emergency response and further influence the accident consequence. Meanwhile, the weight ranking of economic loss, environmental influence, and casualties on social influence is determined with respect to NGPLAs.     

A data-driven narratives skeleton pattern recognition from accident reports dataset for human-and-organizational-factors analysis

Accidents in the process industry involve several interacting factors, including human and organizational factors (HOFs). A long-standing obstacle to HOFs analysis is lack of data. Accident reports are an essential data source to learn from the past and contain HOFs-related data, but they are usually unstructured text in a not standardized format. Some studies have explored the extraction of information automatically from accident reports based on Natural Language Processing (NLP) techniques. However, they were not dedicated to HOFs. Risk communication is considered an essential pillar in safety and risk science. This research develops a HOFs-focused risk communication framework based on the NLP techniques that can support risk assessment and mitigation. The proposed approach automatically extracts the target groups oriented “Who, When, Where, Why” (4Ws) information from accident reports.This framework was applied to explore the eMARS database. The results show that the “4Ws” skeleton of narratives has appreciated performance in pattern recognition and holistic information analysis. The graphical representation interfaces are designed to display the features of HOFs-related accidents, which can better be communicated to the sharp-end operators and decision-makers.