多环芳烃对樟树幼苗土壤微生物的影响

采用室内盆栽实验,定量研究了多环芳烃不同污染水平下樟树幼苗土壤微生物的数量特征.结果表明:多环芳烃改变了土壤中3大类微生物(细菌、真菌、放线菌)的数量及其组成;随着多环芳烃含量的增加,樟树幼苗土壤中细菌、真菌和微生物总数与对照相比均呈下降趋势,放线菌数量4月份的变化特征有所不同;不同多环芳烃含量的土壤中3大类微生物数量都表现为细菌>放线菌>真菌;随着时间的延长,细菌、真菌和微生物总数从10月到翌年4月逐渐增加,4月到7月递减;与对照相比,多环芳烃污染土壤放线菌数量峰值的出现具有时间滞后性.     

基于多环芳烃危害性的环境监测侧重点调查研究

从人类发现多环芳烃具有致癌症肿瘤的严重危害性,并将其作为环境优先污染物至今,各国环境监测部门都公布了优先监测的多环芳烃的种类、浓度或含量。对常见多环芳烃的危害性进行了梳理,并对大气、水体、土壤三种不同载体中多环芳烃的种类及浓度进行了研究,结果发现:大气中的多环芳烃多产生于燃烧活动,居民燃烧产生的多环芳烃浓度比工业燃烧要高;水体中的多环芳烃的种类和含量,与地区的地理位置或城市的功能相关;土壤中的PAHs多通过蔬菜等食物间接进入人体,从而危害人类健康。因此,上述规律为环境监测多环芳烃的侧重点提供了数据及理论基础。     

多指标综合评分法研究姜黄色素的提取工艺

姜黄色素主要含有姜黄素、脱甲氧基姜黄素和二脱甲氧基姜黄素等抗氧化成分。本研究以得率和抗氧化活性为考察指标,在正交试验的基础上,采用多指标综合评分法研究了温度、乙醇体积分数、提取时间和料液比对姜黄色素的得率、二苯基苦基苯肼自由基(DPPH.)和羟基自由基(.OH)清除率的影响。综合评分法得到的姜黄色素优化提取工艺为:提取温度80℃、乙醇体积分数90 %、提取时间1.5h、料液比1∶8(g∶mL),该工艺条件下姜黄色素得率为4.37%,DPPH.清除率8.58%,.OH清除率20.67%。     

樟树色素研究与应用发展现状

樟树色素由樟树叶和果皮提取的红色素、绿色素及其衍生物组成,具有抗氧化性、抑菌性、降血糖、保健等功能活性,是一类来源富足、色彩多样、安全无毒、稳定性较高的天然色素,在食品、纺织、医药和饮料等领域具有巨大的应用潜力和利用价值。为更好地深入研究与开发利用樟树色素,对近年来国内外关于樟树色素的化学组成、理化性质、提取方法、纯化分离、功能活性及应用等方面的研究进行综述,同时对其今后的研究方向与发展前景进行展望。     

全自动索氏提取-气相色谱三重四极杆串联质谱法测定土壤中18种多环芳烃

建立了全自动索氏提取-气相色谱三重四极杆串联质谱法测定土壤中18种多环芳烃的分析方法。土壤经正己烷和乙酸乙酯(1∶1v/v)提取后,硅胶小柱净化,外标法定量。方法对土壤前处理和仪器条件进行了优化,实际测定结果表明:18种多环芳烃含量在2～50μg/L间呈良好的线性关系,相关系数r2均大于0.997;添加0.05～0.50mg/kg浓度,平均回收率在80.2%～92.4%,相对标准偏差(RSD)为3.2%～8.9%,该方法的灵敏度、准确度和精密度均符合测定的技术要求。     

姜黄色素的生物活性和提取分离研究进展

姜黄色素是植物姜黄的有效成分之一,它具有广泛的药理活性.本文论述了姜黄素的抗菌、抗癌、抗氧化、抗炎等生物活性.综述了从姜黄中提取分离姜黄色素的一系列方法,如酶法提取、微波提取、超声提取、超临界流体提取以及大孔树脂分离,以期为开发利用姜黄提供科学依据.     

ABS木塑材料中多环芳烃检测方法研究

研究建立了超声萃取法测定丙烯腈-丁二烯-苯乙烯共聚物(ABS)木塑家具中16种多环芳烃(PAHs)的气相色谱-质谱(GC-MS)方法。以代表性的6种多环芳烃做条件选择,通过正交试验优化,甲苯为提取剂,60℃超声0.5h,萃取液通过气相色谱/质谱-选择离子监测法进行定量分析,16种多环芳烃线性相关系数均大于0.995,方法检出限范围为0.01~0.09 mg/kg,平均回收率80.4%~108.3%,相对标准偏差(n=6)小于10%。该方法简便快速、灵敏度高、定量准确,满足ABS木塑材料中16种多环芳烃的检测要求。     

多环芳烃在土壤-植物系统中的修复研究进展

多环芳烃是一类广泛存在于环境中的有机污染物.综合评述了土壤—植物系统中多环芳烃的含量,阐述了多环芳烃污染土壤的植物修复、微生物修复和植物—微生物联合修复的机理及酶与多环芳烃的相关性,提出了今后研究需重视的问题.     

天然动植物色素的特性及其提取技术概况

综述了天然生物色素在动植物体中的分布和特定生理功能。概括了动植物色素的主要提取方法及其发展状况：直接破碎原料、溶剂浸提、物理技术辅助浸提和现代仪器提取分离等;指出超临界流体萃取(SFE)是较具发展潜力的高效萃取方法,有利于提高色素产品质量。     

多环芳烃及其在土壤中的行为

多环芳烃(PAHs)广泛存在于自然界中,由于它存在的广泛性及其致癌性,EPA规定16种多环芳烃为优先污染物.对多环芳烃来源、在自然界中的分布以及其致癌性做了一个综述,并着重对土壤中多环芳烃的行为做了介绍,包括土壤中PAHs的吸附、迁移转化和降解等.     

Distribution of persistent organic pollutants in aggregate fractions of a temperate forest and semi-rural soil

The fate of persistent organic pollutants(POPs)and their interactions with aggregates of forest soils are not completely understood.Our objectives here were to quantify the distribution of different POPs in waterstable aggregate fractions and to study their influence on soil organic carbon(C_(org)) content.Soil samples were taken from a forest-site,Gogerddan(G) and a semi-rural site,Hazelrigg(H) in Great Britain,from 0–2 and 2–5 cm and 0–4 and 8–12 cm soil depth,respectively.POPs analyzed were PAHs,PCBs,total DDT,PBDEs and HCB.The bulk soil analysis showed that the concentration of POPs was significantly higher(p≤0.05) in forest site G than in semi-rural site H,particularly at the surface soil levels compared to the subsurface soil depths in both sites.Total concentrations of PCBs and PAHs of both sites were positively correlated with C_(org) contents.POPs concentrations and C_(org) ,Ntcontents of forest site G were significantly higher(p≤0.05) in water-stable macro aggregates(0.25,1,2 mm) than the micro aggregates(0.053 mm).The POP concentrations of all aggregate fractions after normalizing to their respective C_(org) content were increased due higher contamination and strong sorption by C_(org) .These results showed a strong effect of C_(org) on the partitioning of organic pollutants to soil aggregate size fractions.The present study affirms the ecological significance of forest soils act as a potential sink of POPs.In summary,our results suggest that aggregate fractions may promote soil C storage and act as a potential POP sink in surface soil without increasing their concentration in the aggregate fraction of subsoil.     

银杏功能活性成分提取分离技术研究进展

概述了银杏天然功能成分黄酮、内酯的化学结构、性质和药用价值,重点介绍了高速逆流色谱、超临界、微波、超声、高效液相色谱等方法的实验原理、优缺点及其在银杏功能成分提取分离中的研究成果,指出了各种技术目前存在的问题,并对银杏功能成分的提取、分离、纯化及深加工产品的开发前景进行了展望。     

六里屯垃圾填埋场调节池生物滤池除臭工程研究

指出了六里屯垃圾填埋场渗滤液臭气是影响六里屯填埋场及周边环境的一个重要因素,其臭气成分主要包括硫化氢、氨气、甲硫醇、甲硫醚、二硫化碳、甲烷等。利用微生物技术对调节池进行了臭气治理,采用惰性填料和生物填料结合的方式,通过添加活性污泥、调节进气量、保证其温湿度及pH值等途径,使调节池出气浓度及周边环境均达到了国家二级标准,有效治理了渗滤液调节池臭气污染。     

活性炭对半乳甘露低聚糖的脱色研究

旨在通过活性炭对半乳甘露低聚糖溶液进行脱色精制,从而提高半乳甘露低聚糖的纯度.首先,运用单因素试验和正交试验方法,获得最佳的脱色条件,最后对脱色后的产物进行红外分析及吸附等温线的测定.研究发现:相比于粉末活性炭和柱状活性炭,颗粒活性炭的选择性脱色精制效果最佳,因此选择颗粒活性炭进行下一步的单因素试验和正交优化试验.首先...     

Use of waste materials as nursery growing media for <Emphasis Type="Italic">Pinus halepensis</Emphasis> production

Peat moss is gradually being replaced by other materials as a growing medium in forest nurseries due to economic and ecological constraints. In this study, six different mixtures were tested, mixing peat moss (P) and pine bark (B) with digested sewage sludge (S) activated sewage sludge (A) and paper mill sludge (M), as growing media for Pinus halepensis seedlings; three different waste doses were applied. Seed germination percentage, seedling growth and foliar nutrient content after 1 year in a greenhouse and percentage survival after transplanting were recorded. The influence of base substrate (P or B) on germination percentage changed in different ways according the type of waste. The order of the different applied mixtures by suitability (germination rate and seedling growth) from best to worst was as follows: activated sludge with peat, activated sludge with pine bark, sewage sludge with peat, sewage sludge with pine bark, paper mill sludge with pine bark and finally paper mill sludge with peat.     

活性炭对柠檬酸及其盐溶液中色素的吸附机理和应用研究

对柠檬酸厂现用的粉状活性炭和林化所科技开发总公司开发的专用活性炭进行了研究 ,对柠檬酸和柠檬酸钠溶液进行了用炭量和脱色力关系的对比实验 ,脱色力表示为 (1-a/A)× 10 0 % ,其a为滤液消光值 ,A为柠檬酸或柠檬酸钠溶液消光值。实验结果表明专用活性炭脱色力高于现用的粉状活性炭 ,同时又测定了这几种活性炭孔径 孔容分布曲线 ,证实了由于专用活性炭吸附有机色素等大分子的有效孔容积大于现用的粉状活性炭 ,是决定专用活性炭脱色效果好的主导因素     

Simple and effective large-scale preparation of geniposide from fruit of Gardenia jasminoides Ellis using a liquid–liquid two-phase extraction

Geniposide was prepared on a large-scale using a selective two-phase liquid–liquid extraction. The aqueous residue from the fruit of Gardenia jasminoides Ellis was treated with sodium carbonate and extracted with n-butanol several times. The n-butanol extracts were treated with activated granular charcoal to remove pigments and were then concentrated to produce a residue with a high solid content. The residue was crystallized to obtain geniposide with 98% purity. For large-scale synthesis, the residue (solid content 45%, geniposide 5.5%) was extracted to generate 70 g of geniposide with 98% purity and 84.8% recovery using 1500 g residue.     

松树皮原花青素的超声提取、超滤膜分离中试研究

通过松树皮原花青素的超声提取、膜分离纯化技术中试试验,考察了超声波提取温度、料液比、提取时间等单因素对原花青素得率的影响,试验得到了超滤膜工作压力、截留分子量的最佳工艺参数。结果表明,采用超声波强化逆流提取松树皮原花青素的最佳参数为：料液比1：12,超声温度60℃,提取时间30min;超滤膜分离纯化工艺参数为：膜工作压力0．2MPa,截留分子量5000。试验获得的松树皮原花青素经检测含量可达95％以上。