A case study of sustainable development in the Sistan-Balochistan province of Iran

Sustainable development is a key factor for economic growth in the twenty-first century. It can be achieved in two stages, the first stage is to conserve and protect forest and other parts of the environment and the second stage is to have an appropriate economic plan to produce more agricultural and industrial goods. This investigation evaluates a possible method for sustainable development in the Sistan-Balochistan Province of Iran. Sistan-Balochistan has the lowest economic growth rate due to severe geographical and environmental constrains.     

Exposure estimates to Fusarium mycotoxins through cereals intake

Mycotoxins are harmful substances produced by fungi in several commodities with a widespread presence in foodstuffs. Human exposure to mycotoxins occurs mainly by contaminated food. The quantitation of mycotoxins in cereal-based food, highly consumed by different age population, is of concern. In this survey, 159 cereal-based samples classified as wheat, maize and rice-based, have been evaluated for the occurrence of patulin, deoxynivalenol, 3-acetyl-deoxynivalenol, fusarenon-X, diacetoxyscirpenol, nivalenol, neosolaniol, HT-2, T-2 and zearalenone by gas chromatography–tandem mass spectrometry. Intakes were calculated for average consumers among adults, children and infants and compared with the tolerable daily intakes (TDI). Data obtained were used to estimate the potential exposure levels. 65.4% of the samples were contaminated with at least one mycotoxin and 15.7% of the analyzed samples showed co-occurrence of mycotoxin. The dietary exposure to HT-2 and T-2 toxins was estimated as 0.010 and 0.086 μg kg⁻¹ bw d⁻¹, amounting to 10% and 86% of the TDI, for adults and infants respectively. These results back up the necessity to take a vigilant attitude in order to minimize human intake of mycotoxins.     

液氦罐车碰撞仿真安全性研究

本文采用s0Mworks、ANSyS／Workbench、LS—DYNA等软件对常温裸形的液氨罐车进行了碰撞仿真研究，获得了多种情形下罐车的碰撞性能，为以后展开实车碰撞提供了重要的技术支撑。     

二元混合液体闪点的计算

以混合溶液纯组分易燃液体闪点的饱和蒸气压为基础,应用乌拉尔定律、双液系的气-液相平衡理论,运用Le Chatelier方程和安托因方程导出二元混合液的闪点计算方法。并例举易燃液体与易燃液体组成的理想混合液、易燃液体与易燃液体组成的非理想混合液、易燃液体与不燃液体组成的非理想混合液的计算过程。乙醇溶液闪点的计算结果与现有的文献资料比较,误差在允许范围内。计算数据用Excel处理,快捷准确,用于确定二元混合液体的火灾危险性。     

Effect of sunlight radiation,rainfall and droplet spectra of sprays on persistence of bacillus thuringiensis deposits after application of dipel® 76af formulation onto conifers

Abstract

The effect of sunlight radiation, rainfall and droplet spectra of sprays on per ‐sistence of a Bacillus thuringiensis subspp. kurstaki (Btk) formulation, DiPel^® 76AF, was examined after application onto spruce [Picea glauca (Moench) Voss] foliage. The investigation consisted of three studies: (i) Study I: a laboratory microcosm study to examine the photostability of DiPel 76AF deposits on foliage after different periods of exposure to two radiation intensities, (ii) Study II: a laboratory microcosm study to examine the rainfastness of foliar deposits after exposure to different amounts of rainfall consisting of two separate droplet spectra, and (iii) Study III: a field microcosm study to investigate the influence of two different droplet spectra of DiPel 76AF sprays on foliar persistence of Btk under natural weathering conditions. In all studies, persistence of Btk was investigated both by bioassay [using spruce budworm (Choristoneura fumiferana Clemens)] and total protein assay.

The findings of Study I indicated that bioactivity of foliar deposits decreased with increasing duration of exposure to radiation, and with increasing radiation intensity. The half‐life (DT₅₀, the exposure period required for 50% of the initial bioactivity to disappear) was 5.1 d for the low intensity, and 3.9 d for the higher intensity. In contrast with the bioassay results, the total protein levels [determined by the bicinchoninic acid (BCA) method] showed no decrease with increasing duration of exposure, or with increasing radiation intensity.

The findings of Study II indicated that bioactivity of foliar deposits decreased with increasing cumulative rainfall. A new term, RF₅₀ [the amount of rain (in mm) required to washoff 50% of the initial deposit], was introduced to understand the relationship between rainfall intensity and reduction in bioactivity. When the same amount of rain was applied in different droplet sizes, the RF₅₀ value was high (5.2 mm) for the small rain droplets, and was low (2.9 mm) for the large rain droplets. Similar to the bioassay results, the total protein concentrations (determined by the BCA method) decreased with increasing amount of rain and with increasing rainfall intensity. The RF₅₀ value (obtained using ng protein /cm²) was 5.4 mm for the small rain droplets, and was 3.4 mm for the large rain droplets.

The field microcosm study indicated that when DiPel 76AF was applied in small droplets (D_v.5 of 65 μm), the persistence of bioactivity was ca 8.0 d, whereas when it was applied in large droplets (D_v.5 of 130 nm) it was ca 11 d. Bioactivity decreased with time after spray, and the DT₅₀ was 1.98 d for the spray of small droplets, and 2.87 d for that of large droplets. Similar to the bioactivity, the total protein concentrations also decreased with time after spray, and the DT₅₀ values for the small and large droplet spectra were 3.45 and 6.07 d respectively.     

China’s Import of Wastes and Its Implications

The trade of wastes in the world has been increasing and China has become the largest importer of wastes. This paper examines the import trend of different wastes and finds out that the total import volume to China approved by the Chinese government keeps increasing and the illegal trade can not be banned despite repeated prohibitions; therefore, China is not only ＂a world factory＂, but actually ＂a global garbage dump＂. In order to well understand the implications of wastes import, this paper further analyzes the resource and environmental effects and risks of different wastes imports as well as the strong driving force of wastes imports. Based on these detailed analysis and solid data, policy recommendations are put forward to reduce the demand for raw materials, to further strengthen the inspection of and supervision over the international trade of the wastes that can be used as raw materials by using the life cycle analysis and risk analysis, to improve the environmental standards and strengthen the disposal capacity, to re-export the raw materials produced from the imported wastes, to develop the long-term planning for the import of wastes and to promote international cooperation.     

Assessment of the use of selected rodents in ecological monitoring

Rodents can be useful in detecting environmental impacts because they are easy to study (easy to capture and handle), they can occur in densities adequate for statistical analysis, and they are ecologically important. In this study the usefulness of rodent populations for ecological monitoring was investigated by examining the effect of variation on the possibility of detecting differences among populations of rodents on 10 trapping grids. The effects of sampling frequencies and dispersal on detecting differences in population parameters among grids was also investigated, as was the possibility of inferring population parameters from correlations with habitat data. Statistically significant differences as small as 4.3Peromyscus maniculatus/ha were detected between grids. Of 10 populations, this comprised 12% of the highest-density population and 44% of the lowest-density population. Smaller and more differences among grids were found by examining only animals surviving from previous months. Dispersal confounds detection of direct impacts to populations, especially during the breeding season. Infrequent sampling fails to detect impacts that occur between sampling periods and will indicate impacts when observed changes result from natural variation. Correlations between population parameters and habitat variables exist but should only be used in predicting, not measuring, impacts. It is concluded that some rodent populations can be used in ecological monitoring. However, intensive sampling is required to account for variation and dispersal.     

基于烦恼改善程度优选噪声控制方案

影响噪声烦恼的声学参量较多,然而在传统噪声控制工程中,往往仅根据A计权声压级所需降低量进行控制方案设计,未能从烦恼改善程度优选方案.为此,本研究提出一种基于烦恼改善程度优选噪声控制方案的方法,并将该方法应用于变电站声屏障噪声控制方案的比选.结果表明,同一声屏障方案对不同关心点噪声烦恼的改善程度差异较大,A计权声压级降低量最大的声屏障方案对噪声烦恼的改善效果未必最好.因此,噪声控制工程设计中,宜根据所关心的声环境保护目标与噪声源的相对位置,选取对保护目标处噪声烦恼改善程度较大的方案.     

微压供热堆压力容器结构设计与力学分析

目的对微压供热堆HAPPY200的压力容器进行结构设计及分析。方法针对HAPPY200的特点,满足堆工、热工等专业要求,完成此微压供热堆堆本体的结构设计,并根据ASME锅炉和压力容器规范(ASME BPVC规范)进行压力容器的力学计算校核。微压供热堆HAPPY200采用池壳结合的方式,反应堆200 MW热功率两回路设计,设计压力1.6 MPa,出口温度120℃。压力容器采用不锈钢材质、35 mm壁厚的设计,采用ASMEBPVC规范对其进行力学计算校核。结果此结构中所得到的力学结果均小于ASMEBPVC标准所要求的限值。结论微压供热堆HAPPY200的压力容器设计满足堆工、热工等专业要求,其力学评定通过ASME BPVC规范要求。     

红枫水库水-气界面二氧化碳分压及扩散通量的时空变化

红枫水库是我国西南喀斯特地区典型的人工湖泊,具有特殊的水文地质特征。准确估算其CO_2排放通量,对了解该水库碳循环具有重要意义。因此,于2017年7月至2018年4月采用走航式监测对库区(南湖和北湖)水气界面二氧化碳分压(pCO_2)和水质参数的时空变化进行了调查。结果表明,红枫水库pCO_2的分布具有明显的时空差异。库区秋、冬季表层水体pCO_2均超过大气pCO_2,表现为CO_2的净排放;春、夏季则相反,表现为CO_2的净吸收。从空间分布上来看,春、秋季北湖pCO_2要明显高于南湖,特别是秋季更为明显。另外,基于高频的走航监测数据,计算得到红枫水库全年CO_2的排放均值约为613mmol/(m~2·d)。