Oxygen intrusion into waste in old landfills of low organic content.

Oxygen invasion into old landfills was studied by assuming the installation of gas venting pipes to promote stabilization of waste. In an experiment using a column pack with old incombustible waste, oxygen intrusion was observed and the oxygen consumption rate was estimated. Oxygen diffused into the waste layer very quickly in the initial stage of the experiment, but oxygen concentration increased only gradually due to reduced gradient and decreasing oxygen consumption. The maximum oxygen consumption rate in packed waste was one-third of that in loosely deposited waste in a beaker measured in a respiration test. A mathematical model was created which fitted the experimental data well and a three-dimensional simulation of a full-scale landfill and a sensitivity analysis were performed.     

基于关联向量机回归的水质预测模型

提出了一种基于关联向量机回归的水质时间序列预测模型,并以该模型对氢离子浓度指数(p H值)、溶解氧(DO)、高锰酸盐指数(CODMn)和氨氮(NH3-N)4种重要水质指标进行预测.首先采用国家环保部发布的四川攀枝花龙洞水质自动监测数据进行实验,对该模型的有效性进行了验证;然后将关联向量机回归预测模型与支持向量机回归预测模型进行比较.为了比较不同核函数的预测效果,实验中预测模型的核函数分别采用了线性函数和高斯函数.实验结果表明,关联向量机回归模型的预测效果不亚于支持向量机回归模型;且在给出预测值时,还能同时给出预测结果的可信程度.     

SNAKES USED IN ETHNOMEDICINE IN NORTHEAST BRAZIL

This paper documents zootherapeutic practices in Northeast Brazil. It is primarily based on field surveys carried out in fishing villages located in the States of Maranhão and Paraíba, where dwellers provided information on snake species used as medicine, body parts used to prepare the remedies, and the illnesses to which the remedies were prescribed. The species used as medicinal drug and their respective families were: Crotalus durissus (rattlesnake), Bothrops leucurus (‘lance head’, a venomous snake), and Lachesis muta (bushmaster) of the family Crotalidae; and Boa constrictor (boa constrictor), Epicrates cenchria (‘salamanta’), and Eunectes murinus (anaconda) of the family (Boidae). These zootherapeutical resources were used for the cure of 14 illnesses. The most commonly cited species were Crotalus durissus (n=26) e Boa constrictor (n=6), Apparently, the medicinal use of snakes does not pose a threat for their population in the studied sites.     

Mass balance of anti-influenza drugs discharged into the Yodo River system,Japan, under an influenza outbreak

In February 2011, at the peak of an influenza outbreak, we performed a comprehensive analysis of the mass balances of four anti-influenza drugs—oseltamivir (OS), oseltamivir carboxylate (OC), amantadine (AMN), and zanamivir (ZAN)—in the urban area of the Yodo River system. This area includes three main river catchments (the Katsura, Uji, and Kidzu Rivers) and is home to 12 million people, about 10% of Japan’s population. Water was sampled at six main rivers and 13 tributary sites and eight sewage treatment plants (STPs). We concluded that the STP effluents were the major sources of the anti-influenza drug load in the Yodo River system (68–94% of total mass fluxes). Extended measurement throughout the Yodo River system further showed only small fluctuations of the ratio of OS to OC from 0.2 to 0.3, suggesting that OS and its metabolite are environmentally stable. The results also clearly showed the importance of reducing the levels of anti-influenza drugs in the water environment by reducing their emission at STPs.     

Degradation of phenol,Asulam and lignin in aqueous solution by Ozonation

Phenol, the herbicide asulam (methylsulfanilyl carbamate) and lignin were degraded by ozonation. The addition of Fe³⁺ did not affect the disappearance rates of phenol and asulam appreciably, whereas UV illumination accelerated the disappearance rate. Fe³⁺ under UV illumination showed only a slight effect on the disappearance rate, but a fairly large effect on TOC elimination. The degradation of the intermediate compounds of asulam including aromatic compounds and organic acids, under UV illumination was accelerated by the addition of Fe³⁺. A possible degradation process of asulam by ozonation was proposed on the basis of intermediate and final products identified.     

Estimation of the respiratory ventilation rate of preschool children in daily life using accelerometers

Inhalation rate is an essential factor for determining the inhaled dose of air pollutants. Here, accelerometers were used to develop regression equations for predicting the minute ventilation rate (V(E)) to estimate the daily inhalation rate in young children. Body acceleration and heart rate were measured in 29 Japanese preschool children (6 yr of age) during nine different levels of activities (lying down, sitting, standing, playing with plastic bricks, walking, building with blocks, climbing stairs, ball tossing, and running) using the Actical omnidirectional accelerometer, the ActivTracer triaxial accelerometer, and a heart rate monitor. Measurements were calibrated against the V(E) measured by the Douglas bag method. ActivTracer accelerometer measurements gave a strong correlation with V(E) (Pearson's r = 0.913), which was marginally stronger than that for the Actical counts (r = 0.886) and comparable to the correlation between heart rate and logarithmic V(E) (r = 0.909). According to the linear regression equation, the V(E) for lying down, sitting, standing, playing with plastic bricks, walking, and running was overestimated by 14-60% by the Actical and by 14-37% by the ActivTracer. By comparison, for building with blocks, climbing stairs, and ball tossing, the V(E) was underestimated by 19-23% by the Actical and by 13-18% by the ActivTracer. When these three activities were excluded, a stronger correlation was found between the V(E) and ActivTracer measurements (r = 0.949); this correlation was 0.761 for the three excluded activities. Discriminant analysis showed that the ratio between vertical and horizontal acceleration obtained by the ActivTracer could discriminate walking from building with blocks, climbing stairs, and ball tossing with a sensitivity of 75%. The error in estimating V(E) was considerably improved for the ActivTracer measurements by the use of two regression equations developed for each type of activity.     

论小城镇核心竞争力的构建和提升

小城镇作为中国城镇化进程的重要组成部分,对于我国城镇发展的作用举足轻重.研究我国小城镇的核心竞争力问题,有助于加深对小城镇经济发展的认识,帮助政府部门从更高的层次制定小城镇经济发展战略.本文界定了小城镇核心竞争力的概念,探讨了培育和提升小城镇经济核心竞争力的重要意义,并从自然环境、人文环境、基础设施、软件环境、创新能力及产业集群等方面对小城镇核心竞争力的构成进行分析;针对小城镇核心竞争力的构建和提升,提出了优化小城镇发展环境,完善小城镇创新体系,增强小城镇产业集群的发展等建议;得出了发展小城镇经济的关键是要增强其竞争力,而要保持小城镇经济持续的竞争优势,关键在于小城镇经济核心竞争力的培育和提升的结论,为促进我国小城镇经济的持续、快速发展及核心竞争力的构建与提升提供参考和借鉴.     

Tsunami mitigation by coastal vegetation considering the effect of tree breaking

Damage to vegetation by tsunami moment and reduction of potential tsunami force are discussed based on a numerical simulation. A numerical model based on two-dimensional nonlinear long-wave equations that include drag forces and turbulence-induced shear force due to the presence of vegetation was developed to estimate tree breaking. The numerical model was then applied to a coastal forest where two dominant tropical vegetation species, Pandanus odoratissimus and Casuarina equisetifolia, were considered. The threshold water depth for tree breaking increased with increasing forest width, and the analysis was consistent with the field investigation results that the critical tsunami water depth for breaking is around 80% of the tree height for P. odoratissimus. C. equisetifolia is stronger than P. odoratissimus against tsunami action, but P. odoratissimus can reduce a greater tsunami force than C. equisetifolia due to its complex of aerial root structures. Even if breakage occurs, P. odoratissimus still has high potential to reduce the tsunami force due to its dense aerial root structures. Previous numerical models that do not include the breaking phenomena may overestimate the vegetation effect for reducing tsunami force. The combination of P. odoratissimus and C. equisetifolia is recommended as a vegetation bioshield to protect coastal areas from tsunami hazards.     

Photodegradation characteristics of PPCPs in water with UV treatment

The degradation characteristics of PPCPs commonly found in surface water under UV treatment were examined for 30 kinds of PPCPs using a UV/Lamp1 that emits light at a wavelength of 254 nm and a UV/Lamp2 that emits light at 254 nm and 185 nm in pure water. When a UV dose of some 230 mJ/cm² was introduced to the 30 PPCPs, photodegradation rates of about > 3% (theophylline) to 100% (diclofenac) and about > 15% (clarithromycin) to 100% (diclofenac) were observed for UV/Lamp1 and UV/Lamp2, respectively. This study also showed that UV/Lamp2, which photolyzes water molecules and generates OH radicals, is more effective for PPCP removal than UV/lamp1. It was postulated that the degradation rates of sulfamethoxazole, sulfamonomethoxine, sulfadimethoxine and sulfadimidine, all, including sulfamethoxazole, derived from sulfanilamide, under UV/Lamp1 resulted mainly from the bond-breaking reactions occurring between –SO₂– and its side atoms, the C–S bond and the N–H bond. Some PPCPs with amide bonds, such as cyclophosphamide and DEET, were highly resistant to photodegradation by UV/Lamp1. AOPs (Advanced oxidation processes) such as the UV/H₂O₂ or UV/O₃ processes should therefore be considered for their potential to remove these substances effectively.     

Trends in hazardous trace metal concentrations in aerosols collected in Beijing, China from 2001 to 2006

Daily observations of hazardous trace metal concentrations in aerosols in Beijing, China were made in the period from 2001 to 2006. We considered coal combustion as a major source of some anthropogenic metals by achieving a correlation analysis and by investigating enrichment factors and relative composition of metals. A possible extra source of some specific metals, such as Cu and Sb, was brake abrasion particles, however, we did not think the transport-related particle was a major source for the hazardous anthropogenic metals even though they could originate from vehicle exhaust and brake/tire abrasion particles. A time-trend model was used to describe temporal variations of chemical constituent concentrations during the five-year period. Several crustal elements, such as Al, Ti, V, Cr, Mn, Fe, and Co, did not show clear increases, with annual rates of change of -15.2% to 3.6%. On the other hand, serious increasing trends were noted from several hazardous trace metals. Cu, Zn, As, Cd, and Pb, which are derived mainly from anthropogenic sources, such as coal combustion, showed higher annual rate of change (4.9-19.8%, p<0.001) according to the regression model. In particular, the Cd and Pb concentrations increased remarkably. We hypothesize that the trend towards increasing concentrations of metals in the air reflects a change that has occurred in the process of burning coal, whereby the use of higher temperatures for coal combustion has resulted in increased emissions of these metals. The increasing use of low-rank coal may also explain the observed trends. In addition, nonferrous metal smelters are considered as a potential, albeit minor, reason for the increasing atmospheric concentrations of anthropogenic hazardous metals in Beijing city.