Regenerable adsorbent for removing ammonia evolved from anaerobic reaction of animal urine

The waste gas evolved from biodegradation of animal urine contains ammonia causing environmental concerns. A new and effective method for removing ammonia from such waste gas using reactive adsorption is presented. In the process, activated carbon impregnated with H2SO4（H2SO4/C） is employed. Ammonia in the waste gas reacts with H2SO4 on the adsorbent instantaneously and completely to form （NIL）2SO4. The H2SO4/C adsorbent is high in NH3 adsorption capacity and regenerable. The NH3 removal capacity of this regenerable adsorbent is more than 30 times that of the adsorbents used normally in the industry. The spent H2SO4/C is regenerated by flowing low-pressure steam through the adsorbent bed to remove the （NH4）2SO4 from the adsorbent. The regeneration by-product is concentrated （NH4）2SO4 solution, which is a perfect liquid fertilizer for local use. Re-soaking the activated carbon with H2SO4 solution rejuvenates the activity of the adsorbent. Thus the H2SOJC can be reused repeatedly. In the mechanism of this reactive adsorption process, trace of H20 in the waste gas is a required, which lends itself to treating ammonia gas saturated with moisture from biodegradation of animal urine.     

生物炭在新疆棉田的应用效果研究

农业是新疆经济和社会的基础,维系着全疆广大农牧民的生计,也关系到民族团结、边疆稳定和各族人民生活水平。寻求新技术提高绿洲农业生产力是新时期新疆经济和社会发展的要求。我们将小麦秸秆生物炭应用于喀什绿洲的灌淤土,研究了其对土壤pH和土壤水分的影响以及对棉花生长和产量的促进作用。结果显示,10%生物炭施用量可以倍增田间持水量,并提高土壤pH值0.36。但后一作用会随土壤灌溉和淋滤作用的增加而降低;在混合施用方式下,生物炭显著提高棉花产量,5%的施用量提高皮棉产量26%。这种增产效果产生的原因是生物炭的施用增加了土壤的营养成分和供水能力,从而增强了植株的株高、果枝数和单株铃数等。但条施方式对棉花的增产效果不显著,其施用过程会伤及作物根系和/或纯生物炭的高碱性影响植株的生理作用,从而造成棉株的枯萎、迟滞作物的生长。上述结果表明生物炭技术是提高绿洲农业生产力很有潜力的一条途径,但施用方式是一个很重要的影响因素。本研究结果不仅可以直接指导新疆绿洲的棉花生产,还可以为我国北方广大干旱区农业生产和管理提供借鉴。     

土壤CO2浓度与地表CO2通量的季节变化及其相互关系

采用气相色谱法对贵州喀斯特地区不同土地利用方式土壤剖面CO2浓度与地表CO2通量的季节变化特征进行为期一年的观测.结果表明:土壤CO2浓度和地表CO2通量具有明显的季节变化规律,均表现为:从春季到夏季浓度和通量逐渐增加,而从秋季到冬季浓度和通量又逐渐降低,这与该区域的温度和降雨量变化趋势一致.不同土地利用方式土壤CO2...     

Aerobic granulation of pure bacterial strain Bacillus thuringiensis

The objective of this study is to cultivate aerobic granules by pure bacterial strain, Bacillus thuringiensis, in a sequencing batch reactor. Stable granules sized 2.0–2.2 mm were formed in the reactor after a five-week cultivation. These granules exhibited excellent settling attributes, and degraded phenol at rates of 1.49 and 1.19 g phenol/(g VSS?d) at 250 and 1500 mg/L of phenol concentration, respectively. Confocal laser scanning microscopic test results show that Bacillus thuringiensis was distributed over the initial small aggregates, and the outer edge of the granule was away from the core regime in the following stage.     

Effects of low temperature on aluminum(Ⅲ) hydrolysis: theoretical and experimental studies

In this study, the effects of low temperature on aluminum(III) (Al) hydrolysis were examined both theoretically and experimentally by constructing a solubility diagram for amorphous aluminum hydroxide (Al(OH)3(am)) and a distribution diagram of hydrolyzed Al species. Firstly, thermodynamic data of Al species at 4℃ were calculated from that at 25℃. A well confirmed polymeric Al species, AlO4Al12(OH)247 (Al13), was involved in building the diagrams and, correspondingly, the non-linear simultaneous equations with 13 degrees were resolved. Secondly, polarized Zeeman atomic absorption spectrophotometry (AAS), 27Al nuclear magnetic resonance (NMR) spectroscopy, and ferron-based spectrophotometry were applied for constructing the practical diagrams. The results show that a decrease of temperature from 25 to 4℃ caused the Al(OH)3(am) boundary on the solubility diagram to shift toward the alkaline side by about 1.0 pH unit and the minimum solubility of Al(OH)3(am) to reduce by 1.0 log unit. The distribution diagram indicates that the monomeric Al, Al13, and solid-phase Al(OH)3 were alternately the predominant species with the increase of pH value during Al hydrolysis. At 25℃, Al13 was the dominant species in a pH range of 4.0 to 4.5, whereas at 4℃, Al13 was the leading species in a pH range spaced from 4.5 to 6.3. The predominant species changed from the monomeric Al to the solid-phase Al(OH)3 over the range of 1.8 pH units at 4℃ in comparison with the range of 0.5 pH unit at 25℃.     

珠海空气中可吸入颗粒物(PM10)的时空变化特征

选取2000年6月-2001年5月珠海空气中PM10的观测数据,分析其在3个监测点(香洲、前山和吉大)的时空演变特征.结果表明,珠海PM10的年均质量浓度为40 μg/m\+3(校正后为52 μg/m\+3),低于国家PM10的二级质量标准,与国内外其他城市相比,珠海PM10相对较低,表明珠海的大气颗粒物污染轻微.2001年4月14,15日珠海PM10日均值显著增高,达到92,127 μg/m\+3,对比香港及北方粉尘源区的颗粒物浓度及气团轨迹分析结果可知,珠海也受到了北方沙尘暴的影响.3个站点的PM10月均质量浓度变化主要表现为夏、秋季低,冬、春季高.珠海市大气PM10的日变化形式以白天高、夜晚低为主.      

元素-锶同位素技术在农产品原产地溯源中的应用

农产品质量安全及其产地溯源是当今世界共同关注的问题。国际上,将元素-同位素技术应用到农产品溯源领域正受到极大关注。通过研究农产品原产地土壤、岩石、降水及地表水等环境因子中元素-同位素组成与农产品之间的对应关系,可定位农产品原产地及其生长地域环境地球化学特征。目前,追溯农产品产地的技术方法存在同位素分馏效应,人为干扰因素...     

三江平原保护区社区居民对湿地生态系统服务功能的贡献意愿

为了解社区对维持保护区湿地生态系统服务功能的贡献意愿,研究选取三江平原5个湿地自然保护区及其社区,依据条件价值评估法设计双边界二分式问卷,进行实地走访调查,从居民社会经济背景等方面探讨影响贡献意愿的因素、居民支付意愿（WTP）和劳动意愿（WTW）的差异。结果表明：1）居民对湿地生态系统服务的劳动意愿（73.57%）高于支付意愿（55.65%）,居民的抗议支付率随WTP和WTW投标值增加呈上升趋势,人均WTP为387.25±7.08元/a,WTW为31.40±0.39 h/月;2）月收入水平较高及对支付金钱有较高接受程度的受访居民,其WTP相对较高;加入环保类协会、对付出劳动的接受程度较高、受教育程度较高及男性的受访居民,则有较高的WTW;3）49.46%的居民愿意同时贡献金钱与劳动,远高于其他贡献意愿类型。建议在保护区的资源保护与管理实践中鼓励社区参与,充分发挥社区居民乐于提供志愿服务时间的贡献意愿。     

Cultural Erosion and Biodiversity: Canoe-Making Knowledge in Pohnpei, Micronesia

Abstract:  Erosion of traditional knowledge and practice is a serious and accelerating problem, but quantitative work on traditional knowledge loss and its importance to biodiversity conservation is lacking. We investigated traditional knowledge of canoe making, a skill heavily dependent on plant biodiversity, on Pohnpei, Federated States of Micronesia, through a survey of 180 island residents. Our results showed that there has been an intergenerational erosion of canoe-making skills. Given current trends, the present generation of Pohnpeians may be the last to retain any knowledge of this traditional craft. We also identified several correlates of knowledge loss—including Western educational level and occupation—that highlight potential avenues for skill conservation via governments, traditional leadership, and schools. These institutions could intervene to emphasize traditional knowledge, which would reinforce institutional contexts in which traditional knowledge and practice is valued. The heightened awareness of the value of biodiversity that is linked to traditional knowledge is key to biological conservation on Pohnpei and can help support local conservation programs.