The toxicity of cadmium ion (Cd2+) to phycocyanin: an in vitro spectroscopic study

Environmental Science and Pollution Research - The pollution of heavy metals is a severer problem for the ecosystems in waters. The toxicity of Cd2+ on phycocyanin (PC) is studied in molecular...     

Recycling sewage sludge into ceramic materials: A review

Environmental Chemistry Letters - Huge amounts of unwanted sewage sludge are generated in the process of wastewater treatment, calling for methods to recycle sewage sludges into value-added...     

System dynamic analysis of construction waste recycling industry chain in China

Environmental Science and Pollution Research - With the acceleration of China’s urbanization process, construction activities have led to a substantial increase in construction waste....     

Slowest of the slow: latitudinal insensitivity of burrowing capacity in the bivalve <Emphasis Type="Italic">Laternula</Emphasis>

Low temperature limits the rate of biochemical reactions and aerobic scopes of cold water ectotherms. To compensate for this limiting effect, animals living in cold environments often possess physiological or morphological adaptations to maintain vital functions. Cross-latitudinal comparison of aerobic capacities is one method to test which factors constrain activity in thermally distinct environments particularly when congeneric studies are carried out on related species with conservative ecology and habitat. Burrowing is a major aerobic activity of bivalve molluscs that is described here for the first time for the tropical mangrove species Laternula truncata and Laternula boschasina and then compared with their Antarctic congener Laternula elliptica. About 80% of L. truncata (16.3–46.1 mm shell length) and 63% of L. boschasina (11.3–27.7 mm shell length) buried within 24 h at 28°C. The burrowing rate index (BRI = [³√wet weight/time to bury]×10⁴) ranged between 1.1 and 20.2 for L. boschasina and 1.1–32.9 for L. truncata. These values are 2–3 orders of magnitude less than other tropical bivalve molluscs and are amongst the lowest recorded for any bivalve. Comparisons with the Antarctic L. elliptica showed little or no differences in BRI (Q ₁₀ of 1.0–1.2 for specimens of the same size). This is contrary to the general pattern over a wide range of bivalves, where BRI increases with a Q ₁₀ of between 2.9 and 6.4 between high latitudes and the equator. L. elliptica has 25–30% longer relative foot length than tropical congeners of the same size, which could be a morphological adaptation compensating for reduced burrowing speeds in a colder environment. Burrowing rates within the genus Laternula could, however, also be maintained by differing habitat, ecological and physiological constraints on burrowing capability.     

Conservation genetics of <Emphasis Type="Italic">Lumnitzera littorea</Emphasis> (Combretaceae), an endangered mangrove,from the Indo-West Pacific

Mangrove forests, with their ecological significance and economic benefits, are vital inter-tidal wetland ecosystems. Lumnitzera littorea (Combreataceae) is a non-viviparous mangrove distributed in tropical Asia and North Australia. Due to natural and human impacts, populations of this species have been isolated, fragmented, and highly disturbed. In China, L. littorea is an endangered species, restricted to small regions of Hainan Island. The genetic composition of five populations of this species from the Indo-West Pacific (South China, Malay Peninsula, Sri Lanka, North Australia) was assessed using inter simple sequence repeat (ISSR) makers. At the species level, expected mean heterozygosity (He) was 0.240 with 75.6% of loci polymorphic (P). However, genetic variation was much lower at the population level (P = 37.1%, He = 0.118). A high coefficient of gene differentiation (Gst = 0.515) and low level of gene flow (Nm = 0.470) indicated significant genetic differentiation among populations. AMOVA also indicated that more than half the total variation (58.4%) was partitioned among populations. The high degree of differentiation observed among populations emphasizes the need for appropriate conservation measures that incorporate additional populations into protected areas, and achieve the restoration of separate, degraded populations.     

湘南第四纪红壤吸附SO_4~(2-)的机理研究

本文研究了湖南第四纪红粘土及其发育的旱地和水田表层土壤对SO_4~2的吸附.结果表明这三种土壤吸附SO_4~2的顺序为;红粘土>旱地红壤>红壤性水稻土.而且随介质pH的升高,SO_4~2吸附量减少,吸附机理也发生改变:当介质pH6.5以后,解吸占优势.     

The Relationship Between Exposure to Arsenic Concentrations in Drinking Water and the Development of Skin Lesions in Farmers from Inner Mongolia, China

Associations between the concentration of arsenic naturally occurring in drinking water and the development of skin lesions in people have been documented for some years at various locations around the world. Data on the exposure-response relationship between concentrations of arsenic in drinking water and prevalence of skin lesions in farmers from five locations in Inner Mongolia, China have been collected from the original publications and re-analysed together as a meta-study. The calculated data show a positive linear exposure-response relationship without a threshold. The reasons for this linear correlation are discussed and compared with the data from Xinjiang, another arsenism area located in a different geographical area of China. Here a different relationship was recorded that involved a threshold concentration before skin lesions developed. The significance of these two different exposure-response scenarios is discussed.     

聚合氯化铝铁絮凝剂的性能研究

煤矸石是采煤过程之废料。本文利用煤矸石制备出了聚合氯化铝铁（ＰＡＦＣ）：一种新型无机高分子絮凝剂，探讨了Ｆｅ＾３＋的稳定性与溶液离子强度之间的关系，发现溶液的离子强度越大，则产生Ｆｅ（ＯＨ）３沉淀时的ＰＨ越高。研究了ＰＡＦＣ水解产物的ζ电位及絮凝效果随ＰＨ的变化情况，比较了ＰＡＦＣ、ＰＡＣ和ＰＦＳ的除浊性能，ＰＡＦＣ在ＰＨ为７．０－８．２范围内除浊效果最佳，ＰＡＦＣ的除浊效果优于ＰＡＣ。     

湘南红壤对NO_3~-和SO_4~(2-)的吸附机理研究

本文研究了湘南第四纪红粘土发育的红壤对NO_3和SO_4~(2-)的吸附等温线。结果表明红壤对NO_3~-的吸附在浓度低时为负吸附,浓度高时为正吸附,吸附机理为非专性吸附,红壤对SO_4~(2-)的吸附等温式以Freundlich方程最好,在达到最大吸量(X_m)之前,SO_4~(2-)以置换羟基(—OH)的配位吸附为主;而在达到最大吸附量以后,以非专性物理吸附为主。     

城市公共安全规划理论与方法的探讨

分析了进行城市公共安全规划研究的意义和理论基础,并对了城市公共安全规划的方法进行了探讨。