兔儿伞中甾体成分的研究

兔儿伞中甾体类化学成分的研究,采用硅胶柱色谱及HPLC等色谱技术进行分离纯化,通过理化性质和波谱数据分析鉴定化合物的结构。从兔儿伞全草正己烷萃取物中分离得到5个甾体类化合物,分别鉴定为:β-谷甾醇(1)、?-波甾醇(2)、β-谷甾醇-3-Ο-β-D葡萄糖苷(3)、豆甾醇(4)、7?-羟基谷甾醇(5)。化合物4,5为首次从该植物中分离得到。     

脱皮马勃化学成分研究

采用硅胶柱色谱等分离方法对脱皮马勃正己烷提取物进行分离纯化,得到5个化合物,依据波谱数据分析鉴定它们的结构分别为:亚油酸(1),3-羰基麦角甾-7,22(E)-二烯(2),3β-羟基麦角甾-7,22(E)-二烯(3),3β-羟基-5α,8α-过氧桥麦角甾-6,22(E)-二烯(4)和苯甲酸(5),其中化合物1和5为首次从脱皮马勃中分离得到。     

多棘海盘车化学成分的分离与鉴定

采用硅胶柱色谱、薄层制备色谱、凝胶柱色谱等手段分离纯化,通过理化常数测定、光谱数据分析和文献对照等方法,对多棘海盘车Asterias amurensis Lutken未被发现的化学成分进行结构鉴定。结果从多棘海盘车中分离得到4种化合物,化合物的结构分别为Phalluside 1(化合物1);N-(胆甾-5-烯-3β-烃基)-3β-醋酸酯-5-乙基-17β-咪唑羧酰胺(化合物2);胆甾-5,20(22)-二烯-3β-醇(化合物3);(2S)-1-O-7溴烷醇甘油(化合物4)。研究表明,化合物1、2、3、4为首次从海盘车属中分离得到的化合物。     

桦褐孔菌三萜类化合物的研究

采用硅胶柱色谱及HPLC等分离方法对桦褐孔菌正己烷提取物进行分离纯化,得到7个三萜类化合物。依据波谱数据分析鉴定它们的结构分别为:白桦脂酸(1),白桦醇(2),羽扇豆醇(3),8,24-羊毛甾二烯-3β,21β-二醇(4),3β-羟基-羊毛甾-8,24-二烯-21-醛(5),8,23(E)-二烯羊毛甾-3β,22(R),25-三醇(6),桦褐孔菌醇D(7)。其中化合物7为首次从野生桦褐孔菌中分离得到。     

东北岩高兰的化学成分研究

研究东北岩高兰的化学成分。采用硅胶柱色谱及HPLC等色谱技术进行分离纯化,通过理化性质和波谱数据分析鉴定化合物的结构。从东北岩高兰的正己烷萃取物中分离得到6个单体化合物,分别鉴定为:3β-羟基-豆甾烷-4-烯-3-酮(1),叶绿醇(2),24-亚甲基环阿尔廷醇(3),β-谷甾醇(4),熊果醇(5),3β-齐墩果醇(6),化合物1-6均为首次从该植物中分离得到。     

鹿心雪茶化学成分研究

采用硅胶柱色谱及HPLC等分离方法对鹿心雪茶正己烷提取物进行分离纯化,得到7个化合物,依据波谱数据分析鉴定它们的结构分别为:3,6-二甲基-2,4-二羟基苯甲酸甲酯(1)、2,4-二羟基-3-醛基-6-甲基苯甲酸甲酯(2)、羊角衣酸(3)、3β-羟基-5α,8α-过氧桥麦角甾-6,22(E)-二烯(4)、3β-羟基-5α,8α-过氧桥麦角甾-6,9,22(E)-三烯(5)、3β-羟基-5α-豆甾烷-4-烯-3-酮(6)、8α,11-elemodiol(7)。其中化合物6和7为首次从该植物中分离的到。     

千根草的化学成分研究

从大戟属植物千根草(Euphorbia thymifolia L.)地上部分丙酮提取物的石油醚部位分离得到5个化合物,经IR、NMR和HRESIMS等波谱技术鉴定为咸南藤酰胺乙酸酯(1)、芹菜素(2)、胡萝卜苷(3)、2,3-环氧-1-硬脂酸甘油酯(4)和顺-10-十七碳烯酸甲酯(5).化合物1为首次从大戟属植物中分离得到;化合物4和5首次从千根草中分离得到;首次报道化合物4的NMR数据.     

铁脚草的化学成分研究

目的:研究铁脚草的化学成分。方法:采用90%乙醇冷渗漉提取,经硅胶柱色谱和凝胶柱色谱Sephadex LH-20进行分离纯化,并采用理化方法和波谱数据分析进行结构鉴定。结果:从铁脚草的90%乙醇提取物中分离并鉴定7个化合物,分别为α-菠菜甾醇、香草醛、槲皮素、木栓酮、丁香脂素、齐墩果酸与α-菠甾醇-3-O-β-D-吡喃葡萄糖苷。结论:化合物香草醛、槲皮素、木栓酮、丁香脂素、齐墩果酸与α-菠甾醇-3-O-β-D-吡喃葡萄糖苷均为首次从该植物中分离得到。     

一匹绸的化学成分研究

目的:对一匹绸的化学成分进行研究。方法:运用色谱方法和光谱技术分离鉴定其化学成分。结果:从一匹绸中分离得到5个化合物,分别为β-谷甾醇(Ⅰ)、羽扇豆醇(Ⅱ)、豆甾-4-烯-3-酮(Ⅲ)、胡萝卜苷(Ⅳ)、3,5-二羟基-4’,7-二甲氧基黄酮(Ⅴ)。结论:化合物Ⅱ、Ⅲ、Ⅴ为首次从该植物中分离得到。     

黄苞南星的化学成分研究

目的:旨在明确黄苞南星的化学成分,从而为研发科学合理的炮制方法以减毒增效,以及质量标准的建立提供物质基础.方法:采用硅胶正相色谱和ODS(C-18)反相色谱等方法研究黄苞南星块茎的化学成分.结果:根据理化性质和波谱数据与已知化合物对照鉴定了6个化合物.分别是脂肪酸类6,7,10-三羟基-(反)-8-十八烯酸(1),甾体化合物qingyangshengenin(2),胡萝卜苷(3),腺苷(4),豆甾醇(5)以及β-谷甾醇(6).化合物4的结构通过单晶衍射实验得到证实.结论:上述化合物为首次从该植物中所分离,进一步丰富了其二次代谢产物的种类.     

Biosorption of La, Eu and Yb using Sargassum biomass

Biosorption of the lanthanides: Lanthanum (La(3+)), Europium (Eu(3+)) and Ytterbium (Yb(3+)) from single-component and multi-component batch systems using Sargassum polycystum Ca-loaded biomass was studied. The ion exchange sorption mechanism was confirmed by the release of calcium ions from the biomass that matched the total number of metal and protons removed from the solution. The metal binding increased with pH due to the decrease of proton concentration in the system, as they also compete for the binding sites. The maximum metal uptake capacity for pH 3, 4 and 5 ranged approximately between (0.8-0.9) mmol g(-1) for La (0.8-0.9) mmol g(-1) for Eu, and (0.7-0.9) mmol g(-1) for Yb. Biosorption from multi-component mixtures was examined at pH 4 using equimolar initial concentrations of the metals. The metal affinity sequence established was Eu>La>Yb, and the maximum metal uptake obtained was 0.29, 0.41, 0.28 mmol g(-1) for La, Eu and Yb, respectively.     

Effect of counterions on lanthanum biosorption by Sargassum polycystum

The effect of the presence of different anions on the biosorption of La(3+) (Lanthanum) using Sargassum polycystum Ca-loaded biomass was studied in this work. Different types of metal salts were used, such as nitrate, sulphate and chloride. The presence of the anion sulphate decreased the metal uptake for tested pH values of 3--5 when compared to the nitrate and chloride systems. The presence of chloride ions did not seem to interfere with the lanthanum removal. The speciation of lanthanum in solution could explain the differences obtained for the different systems and the Mineql+ program was used for the calculations. A monovalent complex with sulphate and lanthanum was formed that had lower apparent affinity towards the biomass compared to the free trivalent metal ion. The La uptake varied from 0.6 to 1.0 mmol g(-1). The Langmuir model was used to describe quantitatively the sorption isotherms. The addition of sulphuric acid for pH adjustment decreased the metal uptake from lanthanum sulphate solutions when compared to the nitric acid addition. The effect was more pronounced with sulphuric acid due to the formation of complexes.     

Column biosorption of lanthanum and europium by Sargassum

Batch and column biosorption of La(3+) (lanthanum) and Eu(3+) (europium) was studied using protonated Sargassum polycystum biomass. The ion exchange sorption mechanism was confirmed by the proportional release of protons and by the total normality of the solution, which remained constant during the process. Equilibrium isotherms were determined for the binary systems, La/H and Eu/H for a total normality of 3 meq g(-1), which produced separation factors of 2.7 and 4.7, respectively, demonstrating a higher affinity of the biomass towards europium. Column runs with a single metal feed were used to estimate the intra-particle mass transfer coefficients for La and Eu (6.0 x 10(-4) and 3.7 x 10(-4) min(-1), respectively). Modeling batch and column binary systems with proton as the common ion was able to predict reasonably well the behavior of a ternary system containing protons. The software FEMLAB was used for solving the set of coupled partial differential equations. Moreover, a series of consecutive sorption/desorption runs demonstrated that the metal could be recovered and the biomass reused in multiple cycles by using 0.1N HCl with no apparent loss in the biosorbent metal uptake capacity.     

Preparation of growth substrate to improve runoff quality from green roofs: physico-chemical characterization,sorption and plant-support experiments

Growth substrate plays an important role in determining the quality of runoff from green roofs. However, no systematic research has been conducted to design a substrate to improve runoff quality. Hence, the present study aimed at designing and developing a green roof substrate using low-cost and environmentally-benign materials. The inorganic fraction of the substrate includes purosil, vermiculite, sand and light-weight clay aggregates (LECA); whereas the organic fraction includes coco-peat and Sargassum wightii. Through factorial design, 13 different substrate mixes were prepared and the optimum mix (20% purosil, 30% vermiculite, 10% sand, 20% LECA, 10% coco-peat and 10% S. wightii) was found to have high water holding capacity (67.6%), air filled porosity (21%), hydraulic conductivity (5524 mm/h) and low bulk density (495 kg/m³). The substrate also provided maximum support for the growth of Portulaca oleracea. Experiments with metal-contaminated influent from the down-flow of a packed reactor revealed that the green roof substrate possesses a high sorption capacity towards various metal ions.     

Nitrous oxide emissions from secondary activated sludge in nitrifying conditions of urban wastewater treatment plants: effect of oxygenation level

In order to better understand the mechanisms of N(2)O emissions from nitrifying activated sludge of urban WWTPs, sludge from the Valenton plant (Paris conurbation) are subjected to lab-scale batch experiments under various conditions of oxygenation. The results show that the highest N(2)O emissions (7.1 microgN-N(2)OgSS(-1) h(-1) in average) occur at a dissolved oxygen (DO) concentration of around 1mgO(2)L(-1). These high emissions at low oxygenation (from 0.1 to 2 mg O(2)L(-1)) are due to two processes: autotrophic nitrifier denitrification and heterotrophic denitrification. Nitrifier denitrification always dominates, representing from 58% to 83% of the N(2)O production. This N(2)O production originating from nitrifying activated sludge becomes 8 times higher when nitrite is added at a DO of 1 mg O(2)L(-1); a decrease is observed both at higher and lower oxygenation. Heterotrophic denitrification represents less than 50% of the N(2)O production, decreasing from 42% to 17% when oxygenation increases from 0.1 to 2 mg O(2) L(-1). We show that ammonium oxidizing bacteria (AOB) can shift to nitrifier denitrification when oxygen is depleted in the environments including in the WWTPs, nitrite then plays the role of oxygen as the final electron acceptor. As opposed to what happens in nitrification, the end products of nitrifier denitrification are gaseous forms of nitrogen, where N(2)O is not negligible compared to N(2). Overall, N(2)O emissions represent 0.1-0.4% of oxidized NH(4)(+), depending on the oxygenation level. N(2)O emissions would range from 0.11 to 0.42 TN-N(2)O day(-1) for a tertiary treatment of the Paris wastewater effluents, consisting exclusively of activated sludge nitrification.     

Study on emission of decomposed chemicals of esters contained in PVC flooring and adhesive

2-Ethyl-1-hexanol (2E1H) is sometimes detected in indoor air at relatively high concentrations. The emission mechanism for 2E1H is considered to be that moisture with a high pH in concrete slabs and self-leveling sub-flooring material reacts with di-2-ethylhexyl phthalate (DEHP) in the polyvinyl chloride (PVC) flooring and compounds containing the 2-ethyl-1-hexyl group in the adhesive. 2E1H is considered to be one of the causes of odor in indoor air and sick building syndrome, so it is important to clarify the 2E1H emission mechanism for IAQ. However, there are few reports on any experimentation into 2E1H emission by chemical reaction involving building materials. In this study, PVC floorings are attached using various adhesives to a self-leveling sub-flooring material that contains water, and their 2E1H emission rates are measured. Furthermore, the components of the adhesives are determined using chemical analysis. It is found that 2E1H emission rates from the floor are affected by the type of adhesive used. On the other hand, some components in the adhesives may suppress the hydrolysis of esters. The hydrolysis of polymers and residual monomers in the adhesive causes 2E1H emission from the adhesive.     

粉砂质泥岩常规力学、蠕变以及应力松弛特性的对比研究

 在相同围压下,对饱和粉砂质泥岩分别进行常规三轴压缩试验、三轴压缩蠕变试验以及三轴压缩应力松弛试验。基于试验结果,比较3种力学试验得出的岩石试样轴向强度大小以及轴向峰值应变大小,并从岩石破裂机制方面解释岩石强度以及变形差异产生的原因。采用Burgers模型描述粉砂质泥岩的蠕变与应力松弛特性,依据模型参数辨识结果,比较常规力学试验得出的剪切模量G与Burgers蠕变模型和应力松弛模型得出的瞬时剪切模量G1大小关系,并比较Burgers蠕变模型与应力松弛模型对应参数值之间的大小关系。研究结果表明：(1) 粉砂质泥岩试样的瞬时强度最大,蠕变长期强度其次,松弛长期强度最小。(2) 常规力学试验中试样的轴向峰值应变最大,应力松弛试验中试样的轴向峰值应变其次,蠕变试验中试样的轴向峰值应变最小。(3) 常规力学参数G值与Burgers蠕变模型和应力松弛模型参数G1值相差较大,分别是蠕变模型和应力松弛模型参数G1值的64.5,86.8倍。(4) 对于G1,G2,?1,?2这4个参数,蠕变模型辨识得出的参数值均较应力松弛模型辨识得出的参数值大。2种模型的G1参数值大小接近,而其他3种参数G2,?1和?2,采用2种模型辨识得出的参数值差别较大,相差1～2个数量级,其中G2参数值相差最小,?1参数值相差最大。与剪切模量G1,G2参数值相比,2种模型的黏滞系数η1,η2参数值相差较大,表明?1,?2对岩石蠕变与应力松弛特性的影响较大。(5) 粉砂质泥岩蠕变与应力松弛模型对应参数的比较结果,证明所得出的岩石蠕变与应力松弛模型参数的正确性,与线黏弹性材料不同,岩石的蠕变特性与应力松弛特性是不等同的,不能简单地由岩石的蠕变特性推导得出其应力松弛特性。     

Is in-stream processing an important control on spatial changes in carbon fluxes in headwater catchments?

Data on small-scale spatial variations in instantaneous fluxes and concentrations of dissolved organic carbon (DOC), dissolved inorganic carbon (DIC) and free carbon dioxide (CO2) are presented for a small acidic headwater stream in NE Scotland. Chloride is used as a conservative element to estimate additional, diffuse inputs of water into the main stem of the stream, other than those from tributaries. Downstream changes in instantaneous carbon fluxes were calculated and then used to estimate losses and gains of carbon within the stream system. Dissolved organic carbon concentrations in the stream ranged from 1.19-6.06 mg l(-1) at its source to a maximum of 10.0-25.3 mg l(-1) as the stream passed through deep peats; DOC concentrations then declined in the lower part of the catchment. DIC concentrations were initially low, increased to 1.5-3.0 mg l(-1) and then decreased to 0.1-1.65 mg l(-1) at the lowest site. Free CO2 concentrations increased from 0.35 mg l(-1) at the stream source to 3.30 mg l(-1) as the stream passed through the peat dominated area. Continually high inputs of CO2-rich water (> 6.0 mg l(-1)) from tributaries maintained these high concentrations in the main stem, until approximately 1.74 km downstream, when there was a rapid decline in concentration. Significant changes in DOC, DIC and CO2 fluxes occur over a distance of 2.7 km downstream from the stream source to the catchment outlet. Between 5.64-41.5 mg C s(-1) as DOC and 2.52-16.2 mg C s(-1) as DIC are removed from the water column. Between 6.81 and 19.0 mg C s(-1) as CO2 is lost along the stream length as progressive equilibration with the atmosphere occurs. We estimate that 11.6-17.6% of the total DOC flux is removed from streamwater by in-stream processes. Dissolved inorganic carbon (HCO3- and free CO2) losses are in excess of nine times its measured flux at the outlet of the catchment. These results suggest that in-stream processing of DOC and DIC and outgassing of CO2 are important controls on the spatial variability of carbon fluxes within headwater streams in upland catchments dominated by organic-rich soils.     

汶川地震作用下约束砌体房屋的抗震能力分析

为验证约束砌体结构的抗震性能,取4栋7层砌体房屋为例进行非线性地震反应分析。4栋房屋中2栋(代号为A1、A2)选自汶川地震影响区的约束砌体房屋,另2栋(代号为B1、B2)为虚拟无筋(或非约束)砌体房屋,除了无任何约束作用的构造措施之外,其他都分别和A1、A2相同。分析中选取汶川地震中基岩和土层场地的共20条地震动作为地震输入。基于分析结果,做了两方面的比较:约束砌体结构房屋地震反应特征和汶川大地震现场调查所见的对比和约束砌体房屋和无筋砌体房屋地震性状的对比。主要结论有:①计算得到的约束砌体房屋在大地震下的震害特征和实际地震相当吻合,结构分析所用的计算模型、恢复力模型和参数取值的可靠性得到验证;②和无筋(或非约束)砌体房屋相比,约束砌体房屋使砌体结构的抗震强度和延性大为改善,具有很好的抗倒塌能力。     

Source characterization using compound composition and stable carbon isotope ratio of PAHs in sediments from lakes, harbor, and shipping waterway

Molecular compositions and compound specific stable carbon isotope ratios of polycyclic aromatic hydrocarbons (PAH) isolated from sediments were used to characterize possible sources of contamination at an urban lake, a harbor, a shipping waterway, and a relatively undisturbed remote lake in the northwest United States. Total PAH concentrations in urban lake sediments ranged from 66.0 to 16,500 microg g(-1) dry wt. with an average of 2600 microg g(-1), which is approximately 50, 100, and 400 times higher on average than PAH in harbor (48 microg g(-1) on average), shipping waterway (26 microg g(-1)), and remote lake (7 microg g(-1)) sediments, respectively. The PAH distribution patterns, methyl phenanthrene/phenanthrene ratios, and a pyrogenic index at the sites suggest a pyrogenic origin for PAHs. Source characterization using principal component analysis and various molecular indices including C2-dibenzothiophenes/C2-phenanthrenes, C3-dibenzothiophenes/C3-phenanthrenes, and C2-chrysenes/C2-phenanthrenes ratios, was able to differentiate PAH deposited in sediments from the four sites. The uniqueness of the source of the sediment PAHs from urban lake was also illustrated by compound specific stable carbon isotope analysis. It was concluded that urban lake sediments are accumulating PAH from sources that are unique from contamination detected at nearby sites in the same watershed.