Reduction of nitrogen excretion and emission in poultry: A review for organic poultry

Organic poultry is an alternative to conventional poultry which is rapidly developing as a response to customers' demand for better food and a cleaner environment. Although organic poultry manure can partially be utilized by organic horticultural producers, litter accumulation as well as excessive nitrogen still remains a challenge to maintain environment pureness, animal, and human health. Compared to conventional poultry, diet formulation without nitrogen overloading in organic poultry is even more complicated due to specific standards and regulations which limit the application of some supplements and imposes specific criteria to the ingredients in use. This is especially valid for methionine provision which supplementation as a crystalline form is only temporarily allowed. This review is focused on the utilization of various protein sources in the preparation of a diet composed of 100% organic ingredients which meet the avian physiology need for methionine, while avoiding protein overload. The potential to use unconventional protein sources such as invertebrates and microbial proteins to achieve optimal amino acid provision is also discussed.     

改性纤维素吸附剂的合成及其对铜离子的吸附

建立了一种简单方便的纤维素改性的固相合成方法。采用普遍廉价的滤纸作为原料,用固相合成法将预处理后的滤纸纤维经琥珀酸酐进行酯化改性,制备成新型的纤维素吸附剂,通过质量增比、扫描电镜、傅里叶红外光谱仪和X射线衍射仪对制备的吸附剂进行了分析表征,并且探究了离子初始浓度、溶液p H和吸附时间对改性纤维素吸附铜离子的影响。结果表明,在室温下初始离子浓度为1 000 mg/L,离子溶液体积为50 m L,加入0.1 g纤维改性剂,p H为4.0~5.0,吸附平衡时间为50 min时,滤纸纤维改性后最大吸附铜离子质量可达470 mg/g,铜离子去除率达到94%。     

流化床生物反应器培养青蒿毛状根生产青蒿素

利用自制的流化床生物反应器进行青蒿毛状根多层培养生产青蒿素．对毛状根在生物反应器生长过程的形态特征进行观察,并在合适的工艺条件下,经２０ｄ分批培养获得生物量干重２１．３ｇ／Ｌ,青蒿素产量３４９．８ｍｇ／Ｌ,并对培养过程中底物消耗的动力学进行了研究．     

ELISA detection of multixenobiotic resistance transporter induction in indigenous freshwater Chironomidae larvae (Diptera): A biomarker calibration step for in situ monitoring of xenobiotic exposure

A new simple and sensitive method to distinguish chemically polluted from unpolluted situations in freshwater ecosystems is reported. For this purpose, Chironomus gr thumni larvae were collected from a polluted urban river downstream a sewage treatment plant. For the first time, ELISA assay was used to semi-quantify the multixenobiotic resistance transporters (MXR) in these small pertinent bioindicators. The use of samples immediately fixed in the field gives a delay to isolate larvae and allows multi-sampling along a longitudinal transect in a river at a given time. Results exhibit an induction of MXR proteins in larvae from the polluted river and a deinduction in larvae maintained 11days in unpolluted water. They show new evidences to use midge larvae in biomonitoring environmental programs. They answer to first biomarker calibration steps for the ongoing development of MXR transporters as a detection tool of xenobiotic impacts on bioindicator invertebrates in their freshwater habitats.     

F-T合成技术生产替代燃料对环境的影响及对策

主要介绍了F-T合成柴油的特性,阐述了其作为清洁能源的优越性;利用生命周期清单分析方法,比较了以煤、生物质及天然气为原料采用F-T合成技术生产替代能源的工艺路线前提下,在提取生产、转化精炼、运输分配、最终用途燃烧、全部燃料链各阶段温室气体排放情况,提出了温室气体的减排对策。     

MALDI-TOF-MS鉴定生物脱氮细菌的方法研究

采用基质辅助激光解吸电离-飞行时间质谱(MALDI-TOF-MS)对生物脱氮废水处理系统中分离得到的两株细菌进行蛋白质质量指纹图谱分析。对供试细菌,比较样品处理方法和基质选择对细菌蛋白质质量指纹图谱的影响,获得优化的实验条件,并对方法的重现性进行了研究。建立了一种快速的细菌蛋白质质量指纹图谱鉴定方法。结果显示:该方法灵敏度高,且分析过程简单快速,具有广泛的开发和应用意义。     

Toxicological effects involved in risk assessment of rare earth lanthanum on roots of Vicia faba L. seedlings

Combined chemical analyses and biological measurements were utilized to investigate potential toxicological effects and possible mechanisms involved in risk assessment of rare earth elements (REEs) on Vicia faba L. seedlings, which were hydroponically cultivated and exposed to various concentrations of lanthanum (La) for 15 days. The results showed that La contents in both the solution and roots increased with the increase of extraneous La, contributing to hormetic dose responses of superoxide dismutase (SOD), catalase (CAT), guaiacol peroxidase (GPX), ascorbate peroxidase (APX) and endoprotease (EP) isozymes activities, and HSP 70 production enhanced at low doses but suppressed at higher doses of La. These physiological responses constituted antioxidant and detoxification systems against La-induced oxidative stress. The elevated La levels also contributed to oxidatively modified proteins, which were most responsible for subsequent cell death and growth retardation of the roots. By combination of hormetic and traditional threshold dose levels, the threshold dose range was deduced to be 108-195 μg La/g dry weight in the roots, corresponding to 0.90-3.12 mg/L of soluble La in the culture solution. It suggests that persistent applications of REEs may lead to potential ecological risk in the environment.     

合成氯蒸汽发生器泄漏分析

本文针对某化肥厂合成氨装置的蒸汽发生器发生泄漏的原因进行了分析。该设备的材质为SA336F22（相当于国内2．25Cr-1Mo）,属于高温高压临氢设备,出现了垂直于焊缝方向的横向裂纹．经分析这些裂纹主要是氢浓度过高而引起的氢致延迟裂纹,并结合实际的情况提出了合适的返修措施。     

镉铅复合胁迫下根表铁锰氧化胶膜厚度对美洲商陆富集镉的影响

为了探讨根表铁锰氧化胶膜厚度及共存离子铅(Pb)对美洲商陆富集镉(Cd)影响,采用水培的方法,诱导培育了胶膜厚度具有极显著差异的美洲商陆(低膜美洲商陆、中膜美洲商陆和高膜美洲商陆),分别进行低Cd低Pb、低Cd高Pb、高Cd低Pb、高Cd高Pb等4种不同金属组合的胁迫处理,观察美洲商陆生长状况、测定植株对Cd的富集量、抗胁迫生理活性物质的表达量.结果表明:中膜和高膜美洲商陆侧根发达,新生根较多,高Cd胁迫对根系发育有较强的抑制作用.高Cd条件下,植株对Cd的富集量为高膜美洲商陆中膜美洲商陆低膜美洲商陆,高膜美洲商陆Cd总富集量可达89765.69 mg·kg-1(以干重计).低Cd条件下,植株对Cd的富集量为低膜美洲商陆高膜美洲商陆中膜美洲商陆.高Pb处理,可提高低膜和高膜美洲商陆Cd富集量,但显著降低中膜美洲商陆Cd富集量.根系分泌的可溶性还原糖含量、叶及根部合成的可溶性蛋白含量与根表铁锰氧化胶膜的厚度成正相关.中膜和高膜美洲商陆叶片及根部可溶性蛋白含量还受到不同金属组合胁迫的影响.镉铅复合胁迫使美洲商陆叶片及根部可溶性蛋白含量极显著高于对照组.     

好氧污泥颗粒化过程中Zeta电位与EPS的变化特性

研究了好氧颗粒污泥在形成过程中Zeta电位、胞外多聚物的变化以及两者之间的关系.通过对污泥调控生长,形成完全颗粒化的好氧污泥.在好氧颗粒形成过程中,污泥的Zeta电位由接种时的-19.1 mV逐渐降至-10.1 mV.完全颗粒化以后,成熟后的好氧颗粒污泥Zeta电位稳定维持在-10 mV左右,说明维持污泥较低的Zeta电位是好氧颗粒污泥形成的重要条件.颗粒化过程中污泥EPS中多糖含量基本不变,蛋白含量增加明显,从13.65 mg.g-1增加到54.12 mg.g-1,蛋白/多糖比值从0.67增加到3.31;污泥的Zeta电位与蛋白/多糖的比值呈正相关,相关系数为0.849,这些结果说明蛋白质对降低污泥表面电位,促进污泥聚集以及好氧颗粒污泥的形成生长等可能起着重要作用.