Organochlorine pesticide residues in cow's milk from a tropical region of Mexico

A monitoring study was conducted to assess the magnitude of DDT [(1,1,1-trichloro-2,2-bis( p -chlorophenyl)ethane)] and HCH (hexachlorocyclohexane) contamination of bovine milk from the central tropical region of Mexico as the chemicals are extensively used in livestock and public-health programmes. Among pesticide residues analysed, the milk samples collected from Tlalixcoyan showed a mean level of γ-HCH (0.128 mg kg -1 ), which was significantly higher than residues in milk samples from Medellin (0.049 mg kg -1 ) and Paso San Juan (0.022 mg kg -1 ). The mean level of pp '-DDE in Medellin samples (0.039 mg kg -1 ) was significantly higher than in Paso San Juan (0.018 mg kg -1 ) and Tlalixcoyan (0.024 mg kg -1 ) milk samples. The pp '-DDT mean level from Medellin milk samples (0.089 mg kg -1 ) was significantly higher than the levels detected in the other two areas. The highest mean Σ-DDT level detected in Medellin samples (0.146 mg kg -1 ) was three times the FAO/WHO tolerance level. The highest acceptable daily intakes calculated for Σ-DDT were 0.017 μg kg -1 bw day -1 for adults and 0.530 μg kg -1 bw day -1 for infants; for γ-HCH residues, they were 0.021 μg kg -1 bw day -1 for adults and 0.666 μg kg -1 bw day -1 for infants, indicating that infants are more exposed to pesticide residues. Results indicate that cattle exposure to HCH and DDT results in high levels in dairy milk and a potential health risk for consumers.     

Analysis of Hydrologic Property of Poyang Lake

1　ＮａｔｕｒａｌＧｅｏｇｒａｐｈｉｃａｌＣｏｎｄｉｔｉｏｎｓＰｏｙａｎｇｌａｋｅｉｓｌｏｃａｔｅｄｉｎｔｈｅｎｏｒｔｈｐａｒｔｏｆＪｉａｎｇｘｉＰｒｏｖ ｉｎｃｅａｎｄｔｏｔｈｅｓｏｕｔｈｏｆＣｈａｎｇｊｉａｎｇＲｉｖｅｒ.ＩｔｒｅｃｅｉｖｅｓｗａｔｅｒｆｒｏｍＧａｎｊｉａｎｇ ,Ｆｕｈｅ ,Ｘｉｎｊｉａｎｇ ,ＲａｏｈｅａｎｄＸｉｕｓｈｕｉｒｉｖｅｒｓ(ｒｅｆｅｒｒｅｄｔｏａｓｆｉｖｅ -ｒｉｖｅｒｓｈｅｒｅａｆｔｅｒ)ｏｆｔｈｅｌａｋｅｓｙｓｔｅｍａｎｄｗａｔｅｒｆｒｏｍＢｏｙａｎｇ ,Ｚｈａｎｇａｎｄ…     

太湖湖内综合治理技术

太湖流域水污染严重，加强治理刻不容缓，除加强陆域污染源（工业点源，生活污水，农业面源）治理外，湖内生态治理已是关键。对污染底泥采用生态疏浚，清除表层0～40cm高营养盐含量的表层沉积物，减轻底泥释放的二次污染，依据陆生植物的养分吸收特点，条用水上种植技术净化富营养化水体，美化水域景观，加强对流域湖泊湿地，河流湿地和河口湿地的保护和建设，实施滨湖水生植被修复是行之有效的措施。     

The Sustainable Utilization of Lake Resources in the Middle and Lower Reaches of Yangtze River

1　ＭａｉｎＰｈｙｓｉｃａｌＣｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆＬａｋｅｉｎｔｈｅＭｉｄｄｌｅａｎｄＬｏｗｅｒＲｅａｃｈｅｓｏｆＹａｎｇｔｚｅＲｉｖｅｒ　　ＴｈｅｌａｋｅｓｉｎｔｈｅｒｅｇｉｏｎｏｆｍｉｄｄｌｅａｎｄｌｏｗｅｒｓｔｒｅａｍｏｆＹａｎｇｔｚｅＲｉｖｅｒｄｉｓｔｒｉｂｕｔｅｒｅｌａｔｉｖｅｌｙｄｅｎｓｅｌｙ．ＴｈｅｗａｔｅｒａｒｅａｗｉｔｈｉｎｔｈｅｄｒａｉｎａｇｅｂａｓｉｎｏｆＹａｎｇｔｚｅＲｉｖｅｒｉｓａｂｏｕｔ 8× 10 4ｋｍ2 ａｎｄｔｈｅｌａｋｅａｒｅａｉｎｔｈｅｒｅｇｉｏｎｏｆｍ…     

Can slurry biogas systems be cost effective without subsidy in Mexico?

Biogas from pig slurry in Mexico has potential to produce 21 PJ per year, equivalent to 3.5% of natural gas consumption in 2013. In this paper, three different scenarios are analysed: mono-digestion of pig slurry in a finisher farm (scenario 1); co-digestion of pig slurry and elephant grass in a finisher farm in situ (scenario 2) and co-digestion of pig slurry and elephant grass in centralised biogas plants (scenario 3). The digesters proposed are anaerobic high density polyurethane (HDPE) covered lagoons. HDPE centralised plants can have capital costs 5 times cheaper than European biogas plants. The economics of utilisation of biogas for electricity generation and as biomethane (a natural gas substitute) were investigated. Economic evaluations for on-site slurry digestion (Scenario 1) and on-site co-digestion of elephant grass and pig slurry (Scenario 2) showed potential for profitability with tariffs less than $US 0.12/kWh_e. For centralised systems (Scenario 3) tariffs of $US 0.161/kWh_e to $US 0.195/kWh_e are required. Slurry transportation, energy use and harvest and ensiling account for 65% of the operational costs in centralised plants (Scenario 3). Biomethane production could compete with natural gas if a subsidy of 4.5 c/L diesel (1 m³ of biomethane) equivalent was available.     

舟曲白龙江堰塞排险与应急疏通减灾工程管理认知

介绍了舟曲白龙江堰塞排险与应急疏通工程的基本情况,叙述了方案编制和完善以及实施组织过程中的关键环节和实际考虑等,从目标决策及系统性、动态性等方面阐明了减灾工程管理在应对自然灾害、抢险救援中的重要意义和作用,对进一步提高科学减灾能力进行了探讨。     

Carbon dioxide (CO2) storage and sequestration of land cover in the Leyte Geothermal Reservation

This study estimated the existing stored carbon (C) and rate of sequestration by vegetation that can potentially serve as a sink for the carbon dioxide emitted from eight geothermal plants in Leyte Geothermal Reservation, Philippines. For the 20,438 ha watershed in the vicinity of the power project, the total C storage is 3.84 Mt C (14.10 Mt CO₂) while C sequestration based on biomass change was 47.35 kt C (173.77 kt CO₂). Relative to power plant emission, the C stored in the reserve is equivalent to more than 22 years of CO₂ emission. Annual C sequestration is 27% of CO₂ emission per year. For the next 25 years, two scenarios were projected. Under Scenario I (“Business as Usual”), the forest reserve will be able to store and sequester more than 32 years of CO₂ emission from the power plants. Under Scenario II (“Accelerated Reforestation”), the reserve will be able to store and sequester about 34 years of CO₂ emission.In addition, the rate of C sequestration based on biomass change in vegetation was recorded to assess the optimum land use that can absorb the carbon dioxide emitted by the power project. These are as follows: tree plantations (10.09 tC/ha/yr)>coconut (4.78 tC/ha/yr)>brushland (4.29 tC/ha/yr)>natural forest (0.92 tC/ha/yr).In terms of cost, the power project operator is spending P1.22 per t CO₂ (P4.4 or US$0.12 per tC) for every year of C storage and sequestration. For 25 years, the total cost is P30.40 per tCO₂ (P111.5 or US$2.94 per tC) which is comparable to the cost of C offset in other tropical countries.     

Volatile constituents of exotic fruits from Brazil

Flavor is one of the main attributes of foods and is given by a combination of volatile molecules present in the matrix. This paper reviews the general characteristics and uses and focuses on the volatile composition of selected Brazilian exotic fruits: Brazilian cherry (Eugenia uniflora), acerola (Malpighia glabra L., Malpighia punicifolia L., Malpighia emarginata DC.), jackfruit (Artocarpus heterophyllus), starfruit (Averrhoa carambola) and fruits from the genera Annona (cherimoya, soursop, sugar apple etc.) and fruits from the genera Spondias (S. purpurea, S. mombin and S. tuberosa). This is information important for flavor industry, which use different aroma compounds for the formulation of fragrances and flavorings to be used in foods, cosmetics and perfumes.     

去除盐湖卤水有机物工艺的工业化应用

盐湖卤水中含有的有机物和泥沙对以盐湖卤水为原料的无机盐产品质量有很大影响。本文以去除盐湖卤水中的有机物为主要目的,在小试的基础上,选出两套工业化方案,并进行了中试,最终优选出一套合理经济的工业化方案,得出絮凝剂配合超滤膜过滤的工艺路线是目前去除盐湖卤水有机物的一种最有效的工业方法。