Recovery elemental sulfur from calcium sulfide prepared by red gypsum in sulfuric acid wastewater treatment

Journal of Material Cycles and Waste Management - Red gypsum comes from TiO2 production industry by sulfate method, which comes from the low acidic liquid stream treatment using lime or limestone....     

Highly efficient photocatalytic oxidation of antibiotic ciprofloxacin using TiO2@g-C3N4@biochar composite

Environmental Science and Pollution Research - In this present study, a novel indirect Z-scheme TiO2@g-C3N4@biochar (TiO2@g-C3N4@BC) composite photocatalyst was successfully fabricated and...     

CdS and Ag synergistically improved the performance of g-C3N4 on visible-light photocatalytic degradation of pollution

Environmental Science and Pollution Research - CdS-AgO@g-C3N4 nanocomposites were successfully synthesized and characterized by XRD, N2 physical adsorption, XPS, SEM, TEM, EDX, and UV–Vis DRS...     

Habitat change and biodiversity loss in South and Southeast Asian countries

Environmental Science and Pollution Research - South and Southeast Asia is by far the most populous region in Asia, with the greatest number of threatened species. Changes in habitat are a major...     

Thermal dependency of burrowing in three species within the bivalve genus <Emphasis Type="Italic">Laternula</Emphasis>: a latitudinal comparison

The upper thermal limits for burrowing and survival were compared with micro-habitat temperature for anomalodesmatan clams: Laternula elliptica (Antarctica, 67°S); Laternula recta, (temperate Australia, 38°S) and Laternula truncata (tropical Singapore, 1°N). Lethal limits (LT₅₀) were higher than burrowing limits (BT₅₀) in L. elliptica (7.5–9.0 and 2.2°C) and L. recta (winter, 32.8–36.8 and 31.1–32.8°C) but the same range for L. truncata (33.0–35.0 and 33.4–34.9°C). L. elliptica and L. truncata had a BT₅₀ 0.4 and 2.4–3.9°C, respectively, above their maximum experienced temperature. L. recta, which experience solar heating during midday low tides, had a BT₅₀ 0.7–2.4°C below and a range for LT₅₀ that spanned their predicted environmental maximum (33.5°C). L. recta showed no seasonal difference in LT₅₀ or BT₅₀. Our single genus comparisons contrast with macrophysiological studies showing that temperate species cope better with elevated temperatures. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

不同湿地植物的根系酸化作用与重金属吸收

为研究不同湿地植物根系分泌物对水体的酸化能力与重金属吸收积累能力间的关系,选用六种对废水中重金属吸收能力较强的湿地植物进行了盆栽实验.这六种湿地植物分别是:稗(Echinochloa crus-galli)、空心莲子草(Alternanthera philoxeroides)、茭笋(Zizania latifolia)、鸭舌草(Monochoria vaginalis)、柳叶箬(Isachne globosa)、辣蓼(Polygonum hydropiper).研究结果表明,不同种类的植物对水体的酸化能力存在明显差异,水体pH差异最大可达0.85个单位;不同湿地植物间对重金属的吸收积累能力有显著差异,而且在重金属积累量方面的差异明显高于重金属浓度方面的差异.相关分析表明,不同湿地植物水体pH与植株重金属积累量之间存在较好的负相关关系,相关系数达到或接近P0.05显著水平.研究结果说明,湿地植物对废水中重金属的吸收积累能力在相当大的程度上取决于其根系分泌物对水体的酸化能力.     

Why Singapore's land transportation energy consumption is relatively low

Since the early 1970s, Singapore has enacted a number of measures to tackle traffic congestion, including measures to restrain vehicle ownership. Although Singapore's per capita GDP is comparable to that of OECD countries, the present car-ownership level in Singapore (10 cars per 100 people) is only a fraction of levels in the OECD countries. Traffic flow in this city-State is relatively smooth, even during peak hours. Although the measures taken were aimed primarily at tackling traffic congestion, they have had other positive impacts, such as reducing energy consumption, air pollution and CO₂ emissions. This article presents an overview of the transportation measures and initiatives in Singapore, and analyses two of the transport demand management measures in detail: the vehicle restraint measure, in particular the unique vehicle quota system introduced in 1990; and the two road pricing systems, i.e. the area licensing scheme (ALS) that operated from 1974 to 1998, and the electronic road pricing system (ERP) that went into operation in 1998. Energy and environmental impacts are then discussed, and finally factors contributing to the success of these schemes. Although certain conditions are unique to Singapore, the experience shows that substantial energy and environmental benefits can be achieved through managing urban transportation system in an integrated and innovative way.     

焦化厂多环芳烃成分谱特征的研究

在焦炉顶端采集颗粒物样品,用气相色谱-质谱联用技术测定了其中13种多环芳烃的含 量.通过与燃煤烟尘和交通隧道中BaP含量的比较,说明焦化作业是造成多环芳烃污染的重要 污染源之一.将分析结果进行归一化处理后,确定了焦化厂多环芳烃成分谱,这一成分谱在轮 廓特征和特征比值方面都表现出与燃煤型污染的相似性,而与交通型污染差别较大.     

Influence of environmental temperature and relative humidity on photocatalytic oxidation of toluene on activated carbon fibers coated TiO2

TiO₂ supported on active carbon fiber (TiO₂/ACF), an absorbable photocatalyst, is a new kind of material applied in air purification. In this paper, the influence of environmental temperature (T) and relative humidity (RH) on the gas-solid adsorption of toluene and the photocatalytic oxidation (PCO) efficiency of adsorbed toluene on TiO₂/ACF were studied, and then, the purification capability of TiO₂/ACF was estimated. PCO results showed that although the PCO efficiency increased under high RH and T levels, the amount of adsorption of toluene decreased. Moreover, quantitative analysis results of intermediates indicated that more environmental risk emerged when PCO of toluene was carried out at higher environmental T and RH levels because more toxic intermediates would be accumulated on the TiO₂/ACF. So, it is significant to control the environmental T and RH conditions in the application of the PCO technique. T = 25°C and RH530% is the optimal condition for purifying toluene in our experimental system.     

土地利用方式对紫色土丘陵区土壤剖面碳、氮影响

采取野外调查与室内分析相结合的方法研究了紫色土丘陵区林地、撂荒地、水田、旱地土壤剖面(0～40 cm)有机碳、全氮变化特征.结果表明.有机碳、全氮均随土层深度增加而逐渐减小,且林地、撂荒地有机碳递减幅度高于水田、旱地.相对于撂荒地和旱地,水田、林地更利于有机碳、全氮的积累.林地有机碳和全氮在0～5 cm土层表现出绝对优势;随土层递增,与水田、撂荒地和旱地的差异逐渐减小.水田有机碳和全氮在大于10 cm土层显示最大值.而撂荒地有机碳和全氮仅在土壤表层高于旱地.有机碳与全氮存在显著正相关关系;w(C)/w(N)随土层深度增加而降低,且林地、撂荒地降低幅度较大.因此相对于水田、旱地,林地和撂荒地w(C)/w(N)仅在0～10 cm显示较大值.可见,土地利用方式对陆地生态系统碳、氮蓄积有明显影响,通过旱地还林或撂荒可以增加土壤特别是表层土壤对碳、氮的积累.