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1.
壳聚糖生产废液的污染治理与综合利用   总被引:1,自引:0,他引:1  
曾德芳  余刚  张彭义  史桢 《环境化学》2002,21(3):288-291
在壳聚糖的生产过程中,将稀碱脱蛋白阶段反应后的稀碱,添加8%-10%的稀碱后可重复使用,如此反复回用3次;而浓碱脱乙酰基阶段反应后的浓碱,添加5%左右的浓碱后可重复使用,如此反复回用10次;最后将酸碱废液综合处理得到熟石灰和有机肥等副产品。与现有的工艺相比,该工艺处理效率提高了3倍,处理成本下降了10倍,污染负荷下降54%。  相似文献   

2.
微波碱解处理剩余污泥的厌氧消化性能   总被引:1,自引:0,他引:1  
为了研究微波碱解预处理(microwave/NaOH pretreatment,MNP)剩余污泥在高温和中温条件下厌氧消化的性能,采用半连续完全混合式反应器分别研究了MNP处理后的剩余污泥在高温厌氧消化工艺(thermophilic anaerobic di-gestion process,TADP)和中温厌氧消化工艺...  相似文献   

3.
马师白  鲁军  高晋生 《环境化学》2002,21(5):454-457
采用高压反应釜,在过热水条件下对PVC脱氯过程进行研究,结果表明,水解工艺可以有效地脱除PVC中的氯,并就工艺条件对脱氯效果的影响进行讨论,适宜的工艺条件为:反应温度220℃,反应时间2h,初始压力3.0MPa,碱浓度4%。  相似文献   

4.
粉防己碱是一种治疗心血管疾病的药物,只能从中药粉防己中提取.近年来粉防己的资源量锐减.防己诺林碱的含量仅次于粉防己碱,至今还没有成为一种药物,是粉防己碱生产时的副产品.为了有效利用这种副产品,本文研究了将防己诺林碱转化为防己碱的方法.在不同的溶剂系统和碱性条件下,以防己诺林碱为原料,采用两种甲基化试剂制备了粉防己碱.结果表明,溶剂、碱性和甲基化试剂等对收率都有很大的影响.其中最优的方法是,硫酸二甲酯为甲基化试剂,二氯甲烷/KOH溶液为溶剂,收率最高,副反应最少,为61.4%.此转化反应能够有效利用粉防己药材.  相似文献   

5.
研究了酸、碱条件下不同化学药品对鸡毛降解的影响,从而筛选出有效的助剂以提高复合氨基酸的产率;并在水解温度恒定、水解剂硫酸3mol·L-1或氢氧化钾6mol·L-1及常压条件下,采用正交试验研究了固液比、助剂用量、水解时间对水解率的影响。结果表明:酸、碱处理条件下不同处理间差异显著,酸处理条件下以金属盐作用效果最好,增产率18. 0%;碱处理条件下以硫化钠作用效果最好,增产率达39. 8%。在水解温度115~120℃及常压条件下,水解剂为3mol·L-1硫酸处理的最佳水解工艺为固液比1∶3、助剂用量120g·kg-1、水解时间10h; 6mol·L-1氢氧化钾作为水解剂时的最佳水解工艺为固液比1∶3、助剂用量120g·kg-1、水解时间12h。  相似文献   

6.
选取盐城滨海湿地典型滩地(互花米草与碱蓬交错区、碱蓬滩)互花米草斑块,研究互花米草和本地种的生长特征、斑块微生境变化和互花米草与本地种的相对竞争力。结果表明:①和本地土著种碱蓬Suaeda salsa、芦苇Phragmites australis相比,入侵种互花米草Spartina alterniflora能更有效地改善微生境,其发达根系能够提高土壤含水量,互花米草的耐盐特性和泌盐作用能够使得互花米草在高盐度环境中生存,并有效的降低土壤盐度;②在互花米草与碱蓬交错区,从互花米草斑块边缘到中心,碱蓬的长势显著变弱,互花米草的长势显著增强,互花米草与碱蓬的相对竞争力为1.94±0.94,互花米草的竞争能力明显强于碱蓬;③在碱蓬滩,从互花米草斑块边缘到中心,碱蓬、芦苇的长势显著变弱,互花米草的长势显著增强,互花米草与碱蓬的相对竞争力为0.87±0.30,互花米草与碱蓬之间的竞争相对平衡;④因此,互花米草可能通过种间竞争不断侵蚀碱蓬生境,从而取代当地土著植被碱蓬和芦苇。  相似文献   

7.
凹叶厚朴中具有α-葡萄糖苷酶抑制活性的成分   总被引:5,自引:0,他引:5  
凹叶厚朴是四川省人工栽种的一种用途广泛的常用中药.在发现凹叶厚朴乙醇提取物具有较强的α-葡萄糖苷酶抑制活性基础上,通过活性跟踪,对该提取物进行了分离,发现其中的生物碱显示了较强的抑制活性.通过溶剂萃取、树脂吸附和反复硅胶柱层析等分离方法从凹叶厚朴乙醇提取物中分离得到6个生物碱.用质谱和核磁共振等波谱方法分别鉴定为木兰箭毒碱,木兰花碱,鹅掌楸碱,蕃荔枝碱,罗默碱和Lysicamine,并应用小肠α-葡萄糖苷酶模型测定了它们对α-葡萄糖苷酶的抑制作用.其中,番荔枝碱和木兰箭毒碱的抑制活性较好,分别为60%和62%;其它4个生物碱成分活性几乎相当,鹅掌楸碱为46%,罗默碱为51%,Lysicamine为49%,木兰花碱为51%.图2参10  相似文献   

8.
通过Al Ferron络合比色动力学分析 ,对Al(Ⅲ )的形态进行了较为准确的划分和计算 ,考察了工艺条件对动力学参数和铝形态分布的影响 .研究表明 ,铝的初始浓度、合成温度对Alb 与Ferron的解离 络合反应的速率常数kb 有一定的影响 ,而碱化度、合成时的搅拌强度和加碱速度对kb 的影响不大 ;碱化度、铝的初始浓度对铝的形态分布影响很大 ,搅拌强度、合成温度和加碱速度对铝的形态分布也有一定的影响 .  相似文献   

9.
天津市清静黄河口河岸翅碱蓬的重金属富集特性   总被引:2,自引:0,他引:2  
对天津市清静黄河口河岸生长的翅碱蓬根茎叶及其生长土壤中铜(Cu)、铅(Pb)、镉(Cd)、铬(Cr)、锌(Zn)、砷(As)和镍(Ni)的含量进行了分析.结果表明,这些重金属元素在污染土壤和翅碱蓬各器官中均发生了明显累积,且累积强度不同.在污染土壤中,Cd的累积强度最弱,Zn的累积强度最强,重金属累积强度顺序为Zn>Cu>Pb>Cr>Ni>As>Cd.翅碱蓬叶部积累了大量的As、Ni和Zn,表明翅碱蓬对As、Ni和Zn的吸收和富集能力较强,而对Cu和Pb的吸收和富集能力较弱,迁移累积率顺序为As>Ni>Zn>Cr>Cd>Cu>Pb.污染土壤上生长的翅碱蓬的生物量远低于正常土壤上生长的翅碱蓬的生物量.图1表5参19  相似文献   

10.
对云南大理地区的10个农贸市场所售土碱中As、Cd、Hg和Pb含量进行测定,并对其食用安全性进行评价。结果表明,供试土碱中重金属含量水平差异很大,As含量为2.79~3.87 mg.kg-1,Hg含量为0.036~0.061mg.kg-1,Cd含量为0~0.015 mg.kg-1,Pb含量为0.15~1.16 mg.kg-1。与相关国家标准相比,所有样品均有不同程度的重金属超标。供试土碱作为食品添加剂时每人每日As、Hg、Cd、Pb摄入量(EDA)均未达到日允许摄入量(ADI)。表明供试土碱对人体健康的潜在危害较小,但为安全起见,应建立土碱环境质量标准并加强管理。  相似文献   

11.
湖南南部铅锌矿区铅锌富集植物筛选研究   总被引:1,自引:0,他引:1  
在湖南省桂阳县铅锌矿区采用调查和室内分析相结合的方法,采集植物和土壤样品112个,分别测定了土壤和植物样品的铅锌含量,筛选铅锌富集植物。结果表明:矿区土壤铅锌污染十分严重,矿区土壤铅和锌的平均质量分数分别为:2177.22、3165.89 mg·kg^-1。植物样品根系的铅锌质量分数分别为:264.00、666.11 mg·kg^-1,地上部铅锌质量分数平均为165.56、363.87 mg·kg^-1,植物根系的铅锌含量与土壤的铅锌含量呈显著正相关。通过对比分析,以地上部铅质量分数大于450 mg·kg^-1、锌质量分数大于750 mg·kg^-1、转运系数大于1、植物地上部形态高大为筛选条件,筛选出5种铅富集植物分别是:糯米团(Hyrtanandra)、水蓼(Polygonum hydropiper)、酸模(RumexacetosaLinn)、毛叶堇菜(Viola verecumda A.Gray)、地榆(Garden Burnet Root);3种锌富集植物分别是:鬼针草(Bidens pilosa L.)、博落回(Macleaya cordata(Willd.) R. Brown)和糯米团;糯米团茎叶的铅锌质量分数分别为635.48、919.51 mg·kg^-1,可作为铅锌复合污染土壤修复的备选植物品种。  相似文献   

12.
裸柱菊(Soliva anthemifolia(Juss.)R.Br.),菊科(Compositae)裸柱菊属(Soliva Ruiz et Pavon.)植物,原产南美洲、大洋洲,1912年在香港发现,现在已经在中国南部广泛分布,其中包括台湾、广东、海南、福建、湖南、浙江、安徽、江西、广西和贵州等地区,为区域性外来恶性杂草。2002年,裸柱菊被国家质量监督检验检疫总局列为中国主要外来杂草及中国重要外来有害植物。裸柱菊的生物学特性表现为地上茎极短,头状花序无梗,直接生于茎基部,花果期全年。裸柱菊的入侵扩散特性为具"湿生性",藉水流入侵、扩散,又适宜沙质性土壤,生活史策略为r-选择,随植物引种扩散蔓延,具强"杂草性"。裸柱菊在菜地生境的生态重要值较大,与鼠麴草(Gnaphalium affine)、鳢肠(Eclipta prostrata)的生态位重叠值较高,与一年蓬(Erigeron annuus)呈正联结,与野茼蒿(Gynura crepidioides)呈负联结,呈现"地域性"。本文对裸柱菊的杂草生态学展开了深入探讨,切断藉水流、植物引种的传播扩散途径,加强预警、监测,有效狙击裸柱菊的进一步蔓延扩散是控制其入侵的重要对策。  相似文献   

13.
Five seagrass species [Halophila ovalis (R.Br) Hook. f., Halodule uninervis (Forsk.) Aschers., Zostera capricorni Aschers., Cymodocea serrulata (R.Br) Aschers. (ed.) and Syringodium isoetifolium (Aschers.) Dandy] from Moreton Bay, Australia, were grown under increased (+25%) and ambient levels of ultraviolet (UV) radiation and photosynthetically active radiation (PAR), and various morphological and physiological responses were examined. Leaf fluorescence ratio (variable:maximum fluorescence) in conjunction with xanthophyll pigment content (violaxanthin, antheraxanthin and zeaxanthin) were used as a measure of photosynthetic efficiency. In addition, absorbance in the UV spectrum, chlorophyll content and chloroplast density were used as indicators of photosynthetic capacity. The seagrass species examined had varying degrees of sensitivity to UV radiation. Halophila ovalis and Halodule uninervis were the most sensitive species, exhibiting the largest decrease in photosynthetic efficiency and chloroplast density and the smallest increase in UV-blocking pigments in response to UV radiation. The more UV-tolerant species, Z. capricorni, C. serrulata and S. isoetifolium, were only significantly affected by increased levels of UV radiation, showing a gradual decline in photosynthetic efficiency and chloroplast density and the largest increases in UV-blocking pigment. UV sensitivity corresponded with leaf morphology, with thicker leaves (as in Z. capricorni, C. serrulata and S. isoetifolium) providing greater morphological protection for UV-sensitive organelles. Not all species were significantly affected by increasing PAR, with decreases in fluorescence ratio and increases in zeaxanthin content observed only in C. serrulata and S. isoetifolium. Sensitivity to PAR corresponded with morphological plasticity; species exhibiting a wide range of growth forms (e.g. Halophila ovalis, Halodule uninervis and Z. capricorni) were the least sensitive to increases in PAR. Seagrass depth-distributions in Moreton Bay appear to be influenced by species sensitivity to UV radiation and PAR, with other factors such as epiphytes, shading and nutrients also affecting species' tolerance. All species were affected to some degree by UV radiation, thus future changes in UV intensity may have repercussions on the distribution of seagrasses.  相似文献   

14.
Distinct morphophysiological variations observed for over 2 years with-in short distances among four perennial plants indicated genetic diversity among the lines growing at three places. The isozyme and SDS polyacrylamide gel banding patterns as genetic markers were used to investigate four perennial species, namely Dalbergia sissoo Roxb., Delonix regia (Boj.) Refin., Cassia fistula L. and Calotropis procera R. Br. Plant materials collected from three locations (Agra, Gwalior and Lucknow) differing in climo-edaphic variables were examined for 4 enzyme systems, viz., esterase, polyphenol oxidase, peroxidase and superoxide dismutase (EST, PPO, PRX and SOD). Among the four isozymes SOD and PRX revealed best discriminating power. Protein banding patterns as well as zymogram revealed that Dalbergia sissoo growing at Gwalior was closer to that of Agra; Delonix regia depicted highest similarity between Lucknow and Agra and Calotropis procera of Lucknow location was more closer to Gwalior than Agra. The results confirm genetic diversity in the species as a means of adaptation to differing climo-edaphic variables.  相似文献   

15.
不同类型水生植物群落对铜绿微囊藻的化感作用   总被引:2,自引:0,他引:2  
田如男  孙欣欣  魏勇 《生态环境》2010,19(9):2149-2154
通过将不同类型水生植物群落种植水与藻类共同培养的方式研究了4种植物群落(群落A:梭鱼草Pontederia cordata+黄菖蒲Iris pseudacorus-水罂粟Hydrocleys nymphoides;群落B:梭鱼草+溪荪Iris sanguinea+黄菖蒲;群落C:梭鱼草+溪荪-大薸Pistia stratiotes;群落D:白花水龙Jussiaea repens-大薸+水罂粟)对铜绿微囊藻Microcystis aeruginosa生长的化感作用。研究结果表明:4种植物群落种植水对铜绿微囊藻均具有较强的抑制作用,且随着群落种植时间的延长,种植水对铜绿微囊藻的抑制作用越强。4个植物群落对铜绿微囊藻生长的抑制作用由大到小依次是:群落A,群落B,群落C,群落D。  相似文献   

16.
To develop the usefulness of plants as bioindicators requires an appropriate selection of plant species which entail an utmost importance for a particular situation. In the present study a periodic evaluation of air pollution tolerance index [APTI] of selected tree species such as Polyalthia longifolia, (Sonner) Thw., Alstonia scholaris, R. Br., Mangifera indica, L., and shrubs Clerodendron infortunatum, L., Eupatorium odoratum, L., and Hyptis suaveolens, (L.) Poit., growing adjacent to the National Highway-47 passing through Thiruvananthapuram District which lies on the south-west coast of India, was carried out with a view to find out the air pollution tolerance as well as sensitivity of the plant species during different seasons. Among the trees in the roadside areas studied, Polyalthia longifolia, (Sonner) Thw., expressed highest APTI values and proved to be a tolerant variety and the others as sensitive species to air pollutants. In the case of shrubs, Clerodendron infortunatum, L., exhibited highest APTI values (7.34) and found to be more tolerant compared to the other two shrub species studied.  相似文献   

17.
鱼腥草对土壤中镉的富集及根系微生物的促进作用   总被引:6,自引:0,他引:6  
通过采集自然条件的鱼腥草和未受污染的土壤,在实验室条件下培育,以及利用镉的筛选,培养出土壤菌悬液,研究了鱼腥草Huttuynia cordata对土壤中镉的富集作用,以及经过根系微生物处理后放线菌对富集后转移的促进作用。结果表明,根部经过微生物处理的鱼腥草地上部(土壤含镉200 mg·kg^-1)有最高的含镉浓度和最大的富集量,分别是是对照组的20倍和50倍。土壤含镉50 mg·kg^-1时,鱼腥草地上部与地下部镉富集量的比例是2.5,高于对照组(1.5)。而当土壤含镉200 mg.kg^-1时,经过处理的鱼腥草地上部与地下部镉含量之比是未经处理的2倍。所以,鱼腥草对土壤中的镉有很强的富集作用,且在根系微生物的促进下,地下部的镉能更有效地转移到地上部,大大加强植物的修复效率;且与其他的诸如添加化学螯合剂等方法相比,土壤根系微生物能更好地适应植物根系环境,更不会对土壤本身的微生态系统造成二次污染。所以研究根系环境中微生物、根系、土壤酶、金属离子等的相互影响关系,将是土壤重金属植物修复的另一重要领域。  相似文献   

18.
Acute toxicity testing of some industrial effluents (rubber (Rr), brewery (Br), and bottling (Bt)) on Chironomus travalensis (Diptera larvae) was determined at 96-h using a static bioassay technique. Effluent quality characterization revealed acidic pH values of 4.5 for Rr, 5.64 for Br, and 4.32 for Bt effluents. Tests were carried out in replicates between 10 and 100% effluent concentrations. Mortality rate rose progressively with increasing concentrations. Bt effluent was the most toxic with 96-h LC50 of 61.5%, closely followed by Rr effluent with 96-h LC50 of 87% and the least toxic was Br effluent with 96-h LC50 of 90%.  相似文献   

19.
Abstract:  Conservation currently relies largely on hindsight because demographic studies identify population decline after the event. Nevertheless, the degree of aggregation within a population is an "instantaneous" characteristic with the potential to identify populations presently at greatest risk of genetic impoverishment (via Allee effects and in-breeding depression) and local decline. We sought to determine the relative extinction risk for sympatric orchid species throughout Monte Barro natural park (Lecco, Italy), based on an index of dispersion ( I ) calculated from the size and location of subpopulations (recorded with GPS and mapped with GIS). Three population dispersion types were identified: (1) highly aggregated and locally abundant (large subpopulations restricted to particular sites; e.g., Gymnadenia conopsea [L.] R.Br.; I = 54.5); (2) widespread and moderately aggregated (opportunistic throughout the elevational range of the mountain; e.g., Listera ovata [L.] R.Br.; I = 18.9); and (3) weakly aggregated and locally rare (small, highly diffuse subpopulations; e.g., endemic Ophrys benacensis [Reisigl] O. & E. Danesch & Ehrend.; I = 4.4). Type 1 populations are more likely to respond to in situ intervention, whereas type 2 are relatively invasive species for which conservation intervention is not necessary, and type 3 are rare species that are least likely to respond to habitat management, for which ex situ conservation and population reinforcement would be most appropriate. Although our methodology provides only a "snapshot" of aboveground patterns of population dispersion, it can help target the application of in situ and ex situ conservation activities proactively and is of particular utility for parks for which a rapid assessment of local extinction risks is needed.  相似文献   

20.
通过营养液水培的方式,研究了在不同浓度溴化1-丁基-3-甲基咪唑([C4mim]Br)对空心菜的毒性效应,测定了[C4mim]Br对空心菜各生长指标、叶绿素含量、丙二醛(MAD)含量以及根系活力的变化情况,同时研究了空心菜对[C4mim]Br的吸收和体内积累特征。结果表明:随着[C4mim]Br处理浓度与培养时间的增加,[C4mim]Br对空心菜各生理生化指标有显著抑制作用,且抑制效应具有剂量依赖型特点,半最大效应浓度(EC_(50))值为1.64 mg·L~(-1)。空心菜体内丙二醛含量显著增加表明[C4mim]Br加剧了细胞膜受损,导致根系对[C4mim]Br的吸收积累能力下降。空心菜的富集系数与转运系数均小于1,表明空心菜可以从环境中吸收并积累[C4mim]Br,但从根到地上部分转运[C4mim]Br能力较弱。  相似文献   

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