藻源污染物特性对高藻水微滤处理过程中膜污染的影响

采用不同生长时期的藻细胞、藻源型有机物(AOM)及原藻液进行过滤实验,研究不同生长时期的藻源污染物对膜污染的影响特性及机制。利用UMFI法分析不同生长时期的藻细胞、AOM及原藻液的污染程度;采用CRITIC分析法定量分析了不同生长时期的AOM和藻细胞在混合过滤过程中对膜污染的贡献率,同时采用混合污染堵塞模型分析了不同生长时期的原藻液不同过滤阶段的主要污染堵塞类型。结果表明, 3个生长时期的藻细胞及AOM的膜污染程度均为对数期最轻;值得注意的是,在原藻液过滤过程中藻细胞及AOM的膜污染贡献率随着生长时期的不同而有所变化,其中AOM的污染权重随着生长时期的延长不断减小,而藻细胞的污染权重随着生长时期的延长不断增大。不同生长时期的原藻液过滤过程中均呈现两段式污染堵塞类型,并且后段均为滤饼堵塞。研究不仅阐明了藻源型污染物特性对微滤处理高藻水膜污染的影响机制,同时也为改善膜污染的技术开发提供参考。     

0.2μm Al2O3陶瓷膜微滤桑菊饮水提液的污染机制研究

目的:研究0.2μmAl2O3陶瓷膜微滤桑菊饮复方水提液过程中的膜污染机理。方法:以桑菊饮复方水提液为研究对象,根据Darcy-Poiseuille定律这一过滤模型确定过滤阻力分布情况,对污染膜表面沉积层的组成物质进行了傅立叶转换红外光谱分析及粒径分析,同时对污染膜表面和截面的进行高分辨扫描电镜观测。结果:①膜阻力主要集中在表面沉积层,浓差极化层阻力起了次要作用,膜本身的阻力及膜孔内部污染阻力所占比例最小。并且,这与通过对SEM图像的分析所得到的结论大致相吻合。②通过红外光谱对膜污染物进行定性分析可知膜污染物中分子主要具有肽键,羰基和羟基。③污染膜表面沉积层的组成物质的粒径分布情况为:占有较大体积百分数的粒子的半径集中在18.627μm左右,而占有较高数量的粒子的半径集中在0.424μm左右。结论:研究微滤过程中的膜污染机理对于采用减缓膜通量减少的措施及寻找有效的膜再生方法有重要指导作用。     

活性无烟煤/滤砂双滤料处理微污染原水

将原普通砂滤池改造为活性无烟煤/滤砂双滤料滤池,当挂膜完成后,进入稳定运行期后活性无烟煤/滤砂双滤料滤池可削减氨氮约2.0～3.50mg/L,对CODMn的去除率为50%～60%,均远高于原普通砂滤池,实践证明,生物活性无烟煤滤池是处理氨氮4.0mg/L以下,CODMn(1.40～5.28mg/L)微污染原水的经济性选择。     

背角无齿蚌对浮游藻类的滤食选择性与滤水率研究

以滇池及其附近水体中分布的背角无齿蚌为研究对象,分析其滤水速率及相关的影响因素,研究其食物组成和滤食浮游藻类的选择性,并初步估算其自然种群的滤水能力和控制浮游藻类的潜力.结果表明,背角无齿蚌的滤水率有一定的日变化,傍晚时较高;滤水率与水体中的悬浮物质含量密切相关,随着悬浮物质浓度增加而减少;滤水率与蚌的个体大小有关,体重增加,滤水率下降.对比水体中与蚌消化道内浮游藻类所占的百分比,发现其对浮游藻类的滤食没有显著的选择性.自然水体中背角无齿蚌的滤水能力很低.     

温度、pH对圆背角无齿蚌滤水率的影响

圆背角无齿蚌（Anodonta woodianapa cifica）是我国重要的经济贝类,广泛分布于各大水系;营底栖生活,通过滤水作用摄食水中的浮游生物和有机碎屑;其肉多壳薄,是优良的动物饵料;在水体生态系统的物质循环和能量流动及水质净化中起着十分重要的作用。     

改性沸石粉吸附去除微污染水中Ni(Ⅱ)的试验研究

用壳聚糖改性天然沸石粉,制备了改性沸石粉吸附材料,对微污染水源水中微量镍(Ⅱ)的吸附去除进行了研究。考察了吸附时间、沸石粉投加量、镍(Ⅱ)初始浓度以及原水pH 值等因素对镍(Ⅱ)去除效果的影响。结果表明,改性沸石粉对镍(Ⅱ)的去除效果明显优于天然沸石粉;当镍(Ⅱ)初始浓度低于0.2 mg/L 时, 投加1.5 g/L 壳聚糖改性沸石粉,经20 min 吸附后,水中镍(Ⅱ)的剩余浓度低于 0.02 mg/L,可满足《生活饮用水卫生标准》(GB5749-2006)中的要求;提高水的pH 值有利于两种沸石粉对镍(Ⅱ)的去除。另外,两种沸石粉对镍(Ⅱ)的吸附过程均符合Freudlich 等温吸附模型,且改性沸石粉的吸附指数更小,其吸附能力更强。     

切应力对内皮细胞膜微粘度的影响

目的：研究切应力对内皮细胞（EC）膜微粘度的影响。材料和方法：将EC置于脉动循环装置中,分别施加15dyne/cm^2,50dyne/cm^2,30Odyne/cm^2切应力,作用Oh,1h,2h,4h,6h,10h后,利用带偏振器的荧光分光光度计测量膜微粘度,结果：切应力使膜微粘度增加,且切应力越高,膜微粘度增加幅度越大。切应力作用4h,EC膜微粘度升至最高,4h-10h,膜微粘度开始缓慢恢复,但仍比静态对照显著升高,结论：在切应力作用下,EC膜微粘度增加,切应力是AS的致病因素,动脉狭窄处和大中动脉分叉处是AS好发的危险部位,也是防治的重点。     

温度、pH 对剑状矛蚌滤水率的影响

测定了剑状矛蚌(Lanceolaria gladiola)在不同温度和不同pH条件下的滤水率.结果表明,在不同温度(10～28℃)条件下,剑状矛蚌的滤水率均随温度升高而上升,达到最大值后呈下降趋势,其中滤水率最大值出现在24℃时,大、中、小个体组剑状矛蚌滤水率最大值分别为0.826 L/h、0.768 L/h和0.65...     

温度、pH对二种淡水贝类滤水率的影响

实验在3m×5m×05m的控温池中进行,以小球藻作投喂饵料,利用直径40cm、高度50cm的陶瓷桶测定了不同规格下5个温度梯度(15、20、25、30、35℃)和5个pH梯度(5、6、7、8、9)背角无齿蚌和三角帆蚌的滤水率,其结果显示①5g左右的三角帆蚌在pH值为7时滤水率最大(0935mlg·min);②平均湿重为(2974±225)g,(611±71)g,(232±54)g的背角无齿蚌的滤水率在20～30℃间较高,以30℃最大,达10884mlg·min。随着规格的增大,背角无齿蚌的滤水率逐渐减少,这种趋势在20、25℃时表现得更为明显。③平均湿重为(3943±307)g,(1055±142)g,(302±58)g的三角帆蚌在水温20、25和30℃时的滤水率均远远大于其它2个温度梯度,中规格蚌的滤水率在30℃最大,大规格和小规格蚌的滤水率均在25℃时最大。     

人红细胞膜和血浆游离脂肪酸成分分析及其对膜微粘度的影响

采用高效液相色谱（ＨＰＬＣ）和荧光偏振技术测定了４２例正常人红细胞膜和血浆游离脂肪酸（ＦＦＡ）及膜微粘度,并探讨了膜脂肪酸和血浆ＦＦＡ构成与膜微粘度之间的关系。结果表明：正常人红细胞膜主要由廿二碳六烯酸（Ｃ２２∶６）、花生四烯酸（Ｃ２０∶４）、亚油酸（Ｃ１８∶２）、软脂酸（Ｃ１６∶０）、油酸（Ｃ１８∶１）和硬脂酸（Ｃ１８∶０）等六种脂肪酸组成。血浆ＦＦＡ构成与膜脂肪酸相似,但不含Ｃ２２∶６而含十四烷酸（Ｃ１４∶０）。红细胞膜各脂肪酸含量大多与其血浆浓度呈明显正相关。红细胞膜微粘度与膜软脂酸和硬脂酸呈明显正相关,与膜廿二碳六烯酸和花生四烯酸呈明显负相关。提示红细胞膜脂肪酸组成受血浆ＦＦＡ成分影响;而红细胞膜脂肪酸成分对膜微粘度亦有重要影响     

INFLUENCE OF A SLIGHT MODIFICATION OF THE COLLODION MEMBRANE ON THE SIGN OF THE ELECTRIFICATION OF WATER

1. It is shown that collodion membranes which have received one treatment with a 1 per cent gelatin solution show for a long time (if not permanently) afterwards a different osmotic behavior from collodion membranes not treated with gelatin. This difference shows itself only towards solutions of those electrolytes which have a tendency to induce a negative electrification of the water particles diffusing through the membrane, namely solutions of acids, acid salts, and of salts with trivalent and tetravalent cations; while the osmotic behavior of the two types of membranes towards solutions of salts and alkalies, which induce a positive electrification of the water particles diffusing through the membrane, is the same. 2. When we separate solutions of salts with trivalent cation, e.g. LaCl₃ or AlCl₃, from pure water by a collodion membrane treated with gelatin, water diffuses rapidly into the solution; while no water diffuses into the solution when the collodion membrane has received no gelatin treatment. 3. When we separate solutions of acid from pure water by a membrane previously treated with gelatin, negative osmosis occurs; i.e., practically no water can diffuse into the solution, while the molecules of solution and some water diffuse out. When we separate solutions of acid from pure water by collodion membranes not treated with gelatin, positive osmosis will occur; i.e., water will diffuse rapidly into the solution and the more rapidly the higher the valency of the anion. 4. These differences occur only in that range of concentrations of electrolytes inside of which the forces determining the rate of diffusion of water through the membrane are predominantly electrical; i.e., in concentrations from 0 to about M/16. For higher concentrations of the same electrolytes, where the forces determining the rate of diffusion are molecular, the osmotic behavior of the two types of membranes is essentially the same. 5. The differences in the osmotic behavior of the two types of membranes are not due to differences in the permeability of the membranes for solutes since it is shown that acids diffuse with the same rate through both kinds of membranes. 6. It is shown that the differences in the osmotic behavior of the two types of collodion membranes towards solutions of acids and of salts with trivalent cation are due to the fact that in the presence of these electrolytes water diffuses in the form of negatively charged particles through the membranes previously treated with gelatin, and in the form of positively charged particles through collodion membranes not treated with gelatin. 7. A treatment of the collodion membranes with casein, egg albumin, blood albumin, or edestin affects the behavior of the membrane towards salts with trivalent or tetravalent cations and towards acids in the same way as does a treatment with gelatin; while a treatment of the membranes with peptone prepared from egg albumin, with alanine, or with starch has no such effect.     

不同胁迫预处理提高水稻幼苗抗寒性期间膜保护系统的变化比较

通过比较盐、冷和热激三种不同胁迫预处理提高水稻(Oryza sativa L.)抗寒性过程中膜保护系统的变化,探讨植物交叉适应机理。结果表明,水稻幼苗经不同胁迫预处理均可提高幼苗的抗寒性。与未预处理苗相比,不同胁迫(冷、热、盐)预处理之间在处理后、低温伤害后及恢复2d后的3个不同时期膜酶促和非酶促保护系统及同工酶酶谱变化各有异同,既有部分共性,也有其独特性。     

磁化水处理菌种在甾体微生物转化过程中的效应

考察了磁化水处理菌种在甾体微生物羟化转化反应中的效应。磁化处理条件为：磁场强度０．２４～０．２５Ｔ、静置式磁化、作用时间３０ｍｉｎ。研究表明经磁化水处理的绿僵菌菌种,完成１１ａ羟化转化甾体底物１６ａ,１７ａ－环氧黄体酮的能力有明显改善,其效应与添加适量生长调节剂时相当,两者配合使用、提前投入底物时效果加强。这有利于发酵周期的缩短。磁化处理后菌种的优良特性可在传代中保持至第３代。     

滤膜法测定水中大肠菌群简便方法的研究

本研究方法为ＩＳＯ９３０８－１规定的滤膜法测定水中大肠菌群的方法,该方法操作简便只需分离和证实两步实验即可得出结果;分离培养基上的阴阳性菌落颜色分明,易于分辩;所用培养基不含致癌物质。本研究方法的准确度高,回收率的均值为９４７％,批内变异系数小于１０％,检出限为５００ｍｌ水样可检出１个ＣＦＵ,检出率是传统方法的３１倍。本研究还探讨了分离培养基的ｐＨ值对菌落颜色的影响。本研究内容经查新在国内尚无报道。     

THE INFLUENCE OF P-RETENTION BY SOILS AND SEDIMENTS ON THE WATER QUALITY OF THE LIONS RIVER

SUMMARY

The soils of Midmar dam catchment and the sediments of the Lions river are shown to have high P-retention properties. Present conditions result in little leaching of PO₄ ^?4 from the soils and favour a net transport of P from overlying water to the sediments. P levels in the water are likely to remain low even if the loading rate of P were increased substantially. It is postulated however that other factors may induce a release of P from the sediments and adversely affect the load carried by the water.     

THE INFLUENCE OF CHOLESTEROL AND CHARGE ON THE MEMBRANE DOMAINS OF ALKYLPHOSPHOLIPID LIPOSOMES AS STUDIED BY EPR

ABSTRACT

Alkylphospholipids are physiologically active derivatives of lipids effective in the treatment of breast cancer. Among them, octadecyl-(1,1-dimethyl-4-piperidino-4-yl)-phosphate (OPP) was demonstrated recently to have the strongest antitumor effect in micellar as well as in sterically stabilised liposome suspension with a low cholesterol content. In this work electron paramagnetic resonance (EPR) was used to study the influence of cholesterol, charge, and sterical stabilisation by PEG₂₀₀₀DSPE on the domain structure and fluidity characteristics of the membrane of OPP liposomes. As a spin probe 5-doxylpalmitoyl methyl ester was used. By computer simulation of the EPR spectra it was found that the experimental spectra are composed of three spectral components, which were attributed to three types of domains with different fluidity characteristics. The EPR parameters as well as the proportions of the individual domains were found to be mainly dependent on the amount of cholesterol, and only to a minor degree on charge and sterical stabilisation. There was a pronounced increase in the proportion of membrane domains with low order parameter, when the molar ratio of cholesterol to OPP was decreased below 1. At the same time the order parameters of all domains decreased, pointing to a transition from a less to a more fluid membrane organisation. These results coincide with an improved therapeutic activity of formulations with a low molar ratio of cholesterol to OPP and indicates that the fluidity characteristics of the membrane may be important for the effectiveness of liposomal alkylphospholipids against breast cancer cells.