The efficacy of five kinds of clay minerals as paraquat adsorbent was discussed in vitro from standpoints of equilibrium amount adsorbed and adsorption rate. The equilibrium amount of paraquat ...adsorbed onto natural aluminium silicate (ADSORBIN) was the largest. The amount of paraquat adsorbed onto clay mineral was large in purified water and normal saline solution, and was small in artificial gastric juice. It was found that the paraquat adsorption onto clay mineral was influenced by the pH of solution rather than the coexistence of sodium cation. It is assumed that the difference in the adsorption rate of paraquat onto clay mineral is based on the interaction between the surface charge of clay mineral and the paraquat cation.
In order to ensure the effective adsorptive removal of orthophosphate ion from solution, the adsorption equilibrium and adsorption rate of orthophosphate ion on activated carbon were measured at ...30°C. The Freundlich equation was applicable to the adsorption isotherms, but an infection was observed in the Freundlich plots of the isotherms. It was concluded that the inflection is a consequence of the pore size distribution of the porous activated carbon. The amounts of orthophosphate ion adsorbed at low concentration and at high concentration seemed to be affected by pH and pore volume, respectively. The adsorption rate of orthophosphate ion into the pores of activated carbon was investigated on the basis of the intraparticle diffusivity (Di') determined by a batch method. The value of Di' changed with the adsorption ratio (F). In the range of constant Di', regardless of F, intraparticle diffusivity was affected by the surface diffusivity rather than the pore diffusivity. The transitional pore volume of activated carbon contributed predominantly to the intraparticle diffusivity of orthophosphate ion.
The concentrations of phosphorus, nitrogen, and other nutritive elements in lakes, bays and inland seas are increased because domestic waste water, the second-step treated water from sewage treatment ...facilities, and the industrial waste water from some plants flow continuously into them. As a result, the waters are eutrophicated and the water quality is lowered, which results in unpalatable drinking water, red lakes, and various other problems. In typical cases, phosphorus acts as an accelerating substance for the growth of algae. Furthermore, phosphorus concentration is used as an indicator of the degree of eutrophication. Either or both of the nutritive elements, i.e., phosphorus and nitrogen, should be removed to prevent this eutrophication. It is difficult to remove nitrogen to a sufficiently low concentration by the ammonia stripping process or the activated sludge process. Therefore, prevention of eutriphication requires the effective removal of phosphorus. The methods for removing phosphorus include the chemical coagulation process, the adsorption process, the ion exchange process, the crystallization process, and the biological dephosphorization process. The coagulation process, which is most widely used, has problems as a result of the cost of chemical injection and the profuse generation of sludge. In the crystallization process and the biological dephosphorization process, on the other hand, there are many technical problems to be solved. Though recently an activated carbon adsorption process is often incorporated in the second-or the third-step liquid-waste treatment, there are very few studies on phosphate adsorption to activated carbon. This may be because activated carbon has been reported to be unsuitable for the adsorption of inorganic ions or lower alcohols. However, now that this process is utilized in practice, it is necessary to obtain detailed data on the properties of phosphate adsorption onto activated carbon. Basic studies on the adsorption treatment of phosphate-containing waste water have been carried out using adsorbents other than activated carbon, such as synthetic aluminium silicate, hydroxyapatite, and ion-exchange resin. These studies have shown that the adsorption of phosphate to such adsorbents proceeds through a chemical adsorption mechanisms. In the present study, the adsorption equilibrium and the adsorption rate of phosphate to activated carbon are examined to obtain basic data on the adsorption-removal treatment of phosphate-containing waste water by activated carbon. The phosphate concentrations were adjusted within the range of those in the first-or the second-step treated water. The adsorbates used are H3PO4, NaH2PO4, KH2PO4, and H6P4O13, which have been reported to be contained in these types of treated water. In addition, the relationships of the pore size distribution of activated carbon to the amount of adsorbate adsorbed and the intraparticle diffusivity are clarified.
Very low density lipoprotein (VLDL) is a major transport vehicle of triglycerides (TG) of endogenous organ in plasma. A major factor determining the amount of TG secreted in VLDL is an availability ...of free fatty acid (FFA) of either exogenous or endogenous origin. From a practical standpoint, a release of VLDL-TG from liver was associated with a level of plasma FFA concentration, and a hydrolysis of VLDL-TG might be dependent on an energic source in human metabolism. It is possible, therefore, that a VLDL-TG play a role on an initiative factor in lipoprotein metabolism. On the other hand, experimental studies using glucose, noradrenaline, and nicotinate in the rabbits showed as follows: 1) Plasma FFA concentration in the rabbits treated with glucose or nicotinate was significantly decreased, while that in the rabbits with noradrenaline was markedly increased as compared with that in the rabbits with saline. 2) Radioactive plasma FFA and VLDL-TG after the infusion of 14C-palmitate were the highest values in the noradrenaline group, but those were the lowest values in the nicotinate group as compared with those in each group. Under the condition loaded with glucose, a significant change in radioactive plasma FFA was not observed, but the radioactive VLDL-TG was increased as compared with that in the control. Additionally, half life of the both plasma FFA and VLDL-TG were more prolonged than those in the other 2 groups. 3) Radioactive TG in adipose tissue was markedly increased by the glucose, while those in the both groups treated with noradrenaline or nicotinate were decreased. These results suggests that a synthesis or a hydrolysis of VLDL-TG is regulated by an energy metabolism. Under the condition utilized FFA as an energic source, VLDL-TG synthesis is apparently accerelated, but it is result from the increased plasma FFA releasing from the adipose tissue. It is possible, therefore, that a release or a synthesis of VLDL-TG is controled by the homeostatic balance which is dependent on a certain level of plasma FFA concentration. Under the condition utilized glucose, plasma FFA is availabled for a VLDL-TG synthesis or an accumulation of TG in adipose tissue. However, VLDL-TG hydrolysis is reduced, and an abnormal lipoprotein metabolism of VLDL to low dencity lipoprotein can be observed at this condition.
A β-k band is one of β-lipoprotein which is separated into a few subunits by polyacrylamide gel-disc electrophoresis. The mechanism and the frequency of the appearance of β-k band in 140 patients ...were studied using disc electrophoresis and ultracentrifugation. The sample having this band was shown a lower TG/protein ratio in low density lipoproteine (LDL) as compared with those without β-k band. In the ratio of TCh/protein, these relations were reversed. In the ratio of TCh/TG in the fraction of very low density lipoprotein (VLDL), the sample with β-k band showed the values more than 0.35, whereas the sample without this band showed the values less than 0.35. According to these findings, the β-k band may be produced by an incomplete hydrolysis of TG in the raction of VLDL.The frequency of β-k band was significant difference between the patients with is chemic heart disease (HID) and the patients without IHD. IHD group showed the value of 31.2 %, control group was 17.6 %. This findings suggested that β-k band was more evident in the patients with IHD than those without IHD.
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