Batch adsorption of organic pollutants from oxidation pond effluents using fly ashes

The batch shaking adsorption study was conducted to determine the potential of fly and volcanic ashes in removing organic pollutants from oxidation pond effluents. Factors affecting organic pollutant removals, such as concentrations and sizes of fly and volcanic ashes, initial pond effluent organic concentrations, washed and unwashed conditions of fly and volcanic ashes, were investigated. The TOC (total organic carbon) removal efficiency varied from 30 to 58 percent. The organic removal efficiency increased with increasing ash concentrations, with decreasing initial pond effluent organic concentrations and with decreasing sizes of ashes.     

Lead and cadmium in teeth,bone and kidneys of rats with a standard Pb‐Cd supply

Male Wistar rats received a combination of 25 ppm PbCl₂ and 5 ppm CdCl₂ in drinking water at different developmental stages. Pb and Cd levels of incisors, molars, epiphyses, diaphyses and kidney cortex were recorded by atomic absorption spectrophotometry. The results confirmed that Pb has an affinity for hard tissue and especially to teeth, but it also accumulated in soft tissues under the above conditions. In addition, the results indicated none or only a moderate placental or mammary barrier for Pb, and suggested a high absorption of lead from the intestine of sucklings. The results also confirmed that kidney cortex is a primary target for Cd, and indicated that Cd has crossed the placental and mammary barriers to some degree. The positive significant correlation between Cd levels in molars and kidney cortex suggested that rodent molars indicate a degree of Cd absorption, whereas incisors do not. It is supposed that rodent molars are comparable to human deciduous teeth. It is thus confirmed that human deciduous teeth indicate previous lead exposure. It is further inferred that they also can be used as indicators of previous Cd‐exposures.     

A short communication on growing Jatropha in Oman

A stripping technique has been used to cencentrate selected hydrocarbons present in water samples at the parts per billion level for analysis by gas chromatography. The chromatograms of hydrocarbons thus stripped from several different water samples show similarities. Washing out of atmospheric pollutants by rainfall is postulated as an explanation of these results. This hypothesis is supported by a comparison of the data with those for trace atmospheric analysis. The comparison shows that the same compounds are present in similar relative amounts both in water samples and the atmosphere. After a period of rain the atmospheric concentrations decrease whilst the water bound concentrations increase.     

A framework of critical resource chain for project schedule analysis

Analysing a schedule is beneficial to help stakeholders understand the scheduled project. Project schedules, which create time plans based on the critical path method (CPM) or on resource‐constrained project scheduling problem (RCPSP) optimization, are targets herein. The Theory of Constraints (TOC) treats a schedule as a system. Schedule elements are suspected constraints and a goal depends on the schedule creation policy. Resource information is further surveyed herein to identify true constraints. A framework is proposed to integrate identified constraints on a schedule, and the critical resource chain concept is introduced. Three scenarios illustrate the proposed framework under different scheduling considerations. Results explain schedule constraints, and several schedule analysis issues are discussed.     

Charged groups synergically enhance protein imprinting in amphoteric polyacrylamide cryogels

Proteins are amphoteric biopolymers with unevenly charged exterior surfaces. Taking this point fully into account could accomplish ingenious recognition systems for the biological macromolecues. Molecularly imprinted polymers (MIPs) are good tools to study the interactions between polymeric matrices and template molecules. Here different protein imprinted cryogels were prepared. Imprinting factors (IFs) were determined with bovine serum albumin (BSA) as the template. The IF of the polymeric cryogel made from only acrylamide (AM) and N,N′‐methylenebisacrylamide (BisAM) is about 1.38. The introduction of charged monomers, either acrylic acid or diallylamine, would increase IFs obviously. One of the basic cryogels gave the maximum IF (about 2.0) of that type. As both acrylic acid and diallylamine were involved, IFs were further increased. An amphoteric cryogel with a suitable acid‐base ratio gave a high IF of about 3.7. Whatever used alone or both, too many added acidic or basic monomers resulted in IF reduction. Taking full advantage of charged groups in MIPs could be a good way to manipulate protein–polymer interactions. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43851.     

An amphoteric poly(VAc‐DBM‐AM‐DMAPS) emulsion focusing on the ecological sand‐fixing in salty desert: Structure and properties

In order to control the impacts of blown sand in salty desert, in this article, the amphoteric emulsion, for the first time, was applied as an ecological sand‐fixing material. This study started from the synthesis of the poly{vinyl acetate‐dibutyl maleate‐acrylamide‐co‐3‐[N‐(2‐methacroyloylethyl)‐N, N‐dimethylammonio]‐propane sulfonate} [P(VAc‐DBM‐AM‐DMAPS)] copolymer emulsion. Then, the structures, composition, thermal property of the emulsion were characterized by ¹H‐NMR, FTIR, and DSC, respectively. The basic properties of the emulsion and salt tolerance of the latex films were measured by using viscometer, dynamic light scattering, and laser Doppler electrophoresis also. And the sand‐fixing properties of the emulsion were evaluated. Finally, the influence of the emulsion on the growth of soil microbe and plants were discussed for understanding its ecological effect. The experimental results showed that the emulsion has been successfully synthesized and could be as an ecological sand‐fixing material. The related reason is that, first, the emulsion could significantly improve the compressive strength and water retaining; second, the emulsion had good thermal aging, freeze‐thaw stabilities and salt tolerance to withstand the changes in temperature and NaCl concentration of salty desert; third, the influence of the emulsion on the growth of plants and microbe of sand also showed a dependable ecological effect. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43715.