Phase Separation Behavior of Aqueous Poly(N-isopropylacrylamide) Solutions Studied by Scattering Experiments.

We have investigated the colloidal phase-separating dilute solution of aqueous poly(N-isopropylacrylamide) (PNIPAM) with a molecular weight of 1.24 × 105 by small-angle X-ray scattering (SAXS) as well as static and dynamic light scattering (SLS and DLS). Those scattering experiments provide us with the average size and size distribution of concentrated-phase droplets and the concentration cconc of the coexisting concentrated phase. While the average droplet size is almost constant above 35 °C in the temperature-scan experiments, it is a decreasing function of temperature above 35 °C in the temperature-jump experiments. This heating rate dependence of the average droplet size arises from the fact that concentrated-phase droplets in the aqueous PNIPAM solution grow only in a limited temperature range (31.5-35 °C). The scattering results on the temperature dependence of cconc are combined with previously reported results of turbidity and DSC, giving the phase diagram of the Type II phase behavior with the off-zero critical point at high molecular weight.

Impacts of Clinical Pharmacist Intervention on the Secondary Prevention of Coronary Heart Disease: A Randomized Controlled Clinical Study.

Coronary heart disease (CHD) is one of the leading causes of morbidity and mortality worldwide, and more efforts should be made to reduce the risk of cardiovascular events. This study aimed to investigate the impact of clinical pharmacist intervention on the prognosis of acute coronary syndrome (ACS) in Chinese patients with CHD. Two hundred and forty patients who had ACS were recruited. Participants were randomly assigned to the intervention group (n = 120) or the control group (n = 120). The intervention group received a medication assessment and education by the clinical pharmacist at discharge and telephone follow-ups at 1 week and 1 and 3 months after discharge. The control group received usual care. The primary outcomes of this study were the proportion of patients who had major adverse cardiovascular events (MACEs), including mortality, nonfatal myocardial infarction (MI), stroke, and unplanned cardiac-related rehospitalizations within 6 and 12 months after hospital discharge. Secondary outcome was self-reported medication adherence to evidence-based medications for CHD (antiplatelets, statins, ß-blockers, and angiotensin-converting enzyme inhibitors or angiotensin receptor blockers). Of 240 enrolled patients, 238 (98.3%) completed 6-month follow-up, and 235 (97.9%) completed 12-month follow-up. There were no significant differences between intervention and control groups in the percentages of patients who incurred MACEs within the 6-month follow-up (3.3% vs 7.6%, respectively, P = 0.145) or 12-month follow-up (10.9% vs 12.1%, respectively, P = 0.783). Significant improvements were found in the prescribing rates of ß-blockers and all four classes of medications at discharge in the intervention group compared with the control group (P = 0.001 and P = 0.009, respectively). There was no significant difference between the intervention and control groups in the use of all four classes of medications at the 6-month follow-up (48.3% vs 45.8%, respectively, P = 0.691) and 12-month follow-up (47.9% vs 46.6%, respectively, P = 0.836). The use of ß-blockers was nonsignificantly higher in the intervention group than in the control group at the 6-month follow-up (74.2% vs. 64.4%, P = 0.103) and 12-month follow-up (74.8% vs 63.8%, P = 0.068). Clinical pharmacist intervention had no significant effects on reduction in cardiovascular events among patients with CHD. Further studies with larger sample sizes and longer time frames for both intervention and follow-up are needed to validate the role of the clinical pharmacist in the morbidity and mortality of CHD. Clinical Trial Registration: chictr.org.cn, identifier ChiCTR-IOR-16007716.

Comparing removal of trace organic compounds and assimilable organic carbon (AOC) at advanced and traditional water treatment plants.

Stability of drinking water can be indicated by the assimilable organic carbon (AOC). This AOC value represents the regrowth capacity of microorganisms and has large impacts on the quality of drinking water in a distribution system. With respect to the effectiveness of traditional and advanced processing methods in removing trace organic compounds (including TOC, DOC, UV(254), and AOC) from water, experimental results indicate that the removal rate of AOC at the Cheng Ching Lake water treatment plant (which utilizes advanced water treatment processes, and is hereinafter referred to as CCLWTP) is 54%, while the removal rate of AOC at the Gong Yuan water treatment plant (which uses traditional water treatment processes, and is hereinafter referred to as GYWTP) is 36%. In advanced water treatment units, new coagulation-sedimentation processes, rapid filters, and biological activated carbon filters can effectively remove AOC, total organic carbon (TOC), and dissolved organic carbon (DOC). In traditional water treatment units, coagulation-sedimentation processes are most effective in removing AOC. Simulation results and calculations made using the AutoNet method indicate that TOC, TDS, NH(3)-N, and NO(3)-N should be regularly monitored in the CCLWTP, and that TOC, temperature, and NH(3)-N should be regularly monitored in the GYWTP.

Variation and removal efficiency of assimilable organic carbon (AOC) in an advanced water treatment system.

This study investigates the microorganism growth indicator and determines the assimilable organic carbon (AOC) content at the Cheng-Ching Lake Advanced Water Treatment Plant (CCLAWTP) in Kaohsiung, Taiwan. Notably, AOC is associated with the biological stability within the water distribution network and has garnered considerable attention in the environmental engineering field in recent years. Water samples were collected from the effluent of each unit in CCLAWTP once monthly during December 2008 to November 2009. Items of water quality related to carbon concentration levels, including AOC, total organic carbon, dissolved organic carbon, UV(254), and specific ultraviolent absorbance were analyzed. Analytical results demonstrate that the average AOC concentration in raw water was 83.61 µg/L and reduced in freshwater was controlled at an average of 50 µg/L after an advanced treatment system of roughly 54% of AOC was removed in compliance with treatment plant standards. If AOC concentrations in freshwater can be reduced, study results can provide a direction for improving water treatment capabilities.

Generation of disinfection by-products (DBPs) at two advanced water treatment plants.

A sampling program was conducted to investigate the formation of disinfection by-products (DBPs) and dissolved organic carbon (DOC) at two advanced water treatment plants in Kaohsiung City, Taiwan. The results in this study can be used as a reference for the operational control of water treatment plants and the setting of regulations in Taiwan. Samples of drinking water were collected from two advanced water treatment plants from June 2007 to April 2008. Changes in the concentration of dissolved organic carbon, the trihalomethane formation potential, and the haloacetic acids formation potential were measured in raw water samples. Variations in the concentrations of trihalomethanes (THMs) and haloacetic acids (HAA(5)) in finished drinking water were evaluated. The major species of HAA(5) were in the order of dichloroacetic acid and trichloroacetic acid and the THM was of trichloromethane. DOC was strongly related to DBPs in raw water. In this investigation, the removal efficiency of DBPs in Plant A (ultrafiltration/reverse osmosis system) exceeded that in Plant B (ozonation/biological activated carbon system). Both advanced water treatment plants greatly improved the quality of drinking water.

Treatment of printed circuit board industrial wastewater by Ferrite process combined with Fenton method.

Printed circuit board wastewater typically contains organics and metal ions. The study explored the feasibility of a sequential procedure, FFP (the combination of the Fenton method and the Ferrite process), for treating printed circuit board wastewater, and established the optimum parameters for it. The analytical results showed that the proper pH level was 2 for Fenton oxidation, and the appropriate H2O2 dosing type was batch dosing. For the Ferrite process, the suitable Fe/M (Fe is the total dose of Fe2+ added to a solution and M is the initial total moles of various metal ions in untreated wastewater) molar ratio was 10 and the sludge met the toxicity characteristic leaching procedure (TCLP) standards. Following FFP treatment, effluent water or sludge easily met Taiwan's standards. Finally, the SEM/EDS test demonstrated that particle sizes of the sludge were approximately 50-80 nm, and the saturation magnetization was 67.5 emu/g.

Assessing water quality of drinking water distribution system in the South Taiwan.

This investigation conducted a full-scale survey the drinking water distribution system in Kaohsiung city, Taiwan. The aim was to investigate whether the distribution system was capable of maintaining high water quality from the water treatment facilities through to the end user. The results showed that the distribution system can maintain high water quality, except for suitable chlorine residuals. The authors plotted chlorine residual contour maps to identify areas with low chlorine residuals, helping them prioritize sections that must be flushed or renewal. The contour maps also provide sufficient and clear information for locating booster chlorination stations. Contour maps enable water facilities to identify how water quality decays in the distribution systems and the locations of such decay. Water quality decay can be caused by properties of pipeline materials, hydraulic conditions, and/or biofilm thickness. However, understanding the exact reasons is unnecessary because the contour maps provide sufficient information for trouble-shooting the distribution systems.

Influence of alkalinity, hardness and dissolved solids on drinking water taste: A case study of consumer satisfaction.

Two surveys of consumer satisfaction with drinking water conducted by Taiwan Water Supply Corp. are presented in this study. The study results show that although a lot of money was invested to modify traditional treatment processes, over 60% of local residents still avoided drinking tap water. Over half of the respondents felt that sample TT (from the traditional treatment process) was not a good drinking water, whether in the first or second survey, whereas almost 60% of respondents felt that samples PA, PB, CCL and CT (from advanced treatment processes) were good to drink. For all drinking water samples, respondent satisfaction with a sample primarily depended on it having no unpleasant flavors. Taiwan Environmental Protection Administration plans to revise the drinking water quality standards for TH and TDS in the near future. The new standards require a lower TH concentration (from currently 400mg/L (as CaCO(3)) to 150mg/L (as CaCO(3))), and a lower TDS maximum admissible concentration from the current guideline of 600 to 250mg/L. Therefore, this study also evaluated the impacts on drinking water tastes caused by variations in TH and TDS concentrations, and assessed the need to issue more strict drinking water quality standards for TH and TDS. The research results showed that most respondents could not tell the difference in water taste among water samples with different TDS, TH and alkalinity. Furthermore, hardness was found to be inversely associated with cardiovascular diseases and cancers, and complying with more strict standards would lead most water facilities to invest billions of dollars to upgrade their treatment processes. Consequently, in terms of drinking water tastes alone, this study suggested that Taiwan Environmental Protection Administration should conduct more thorough reviews of the scientific literature that provides the rationale for setting standards and reconsider if it is necessary to revise drinking water quality standards for TH and TDS.