Physicochemical properties of chars at different treatment temperatures

In this study, the physicochemical properties of the char of Indonesian SM coal following heat treatment at various temperatures were evaluated using X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and morphological and specific surface area analysis. Based on these analyses, heat treatment of coal was determined to be the most effective in increasing the coal rank. In the XPS analysis, the C–O and C–O–C groups and quaternary-N species were found to be of a lower grade coal when the pretreatment temperature decreased, meanwhile the C–C group and pyridinic species increased. In the FT-IR analysis, the collapse of the C–O and C–O–C group was observed due to the collapse of the ether group. In SEM and Brunauer–Emmett–Teller (BET) analysis, a decrease in the ether group was shown to be accompanied with the formation of micropores.

Implications Recently, XPS analyses have been reported as coal surface analysis. Usually, they have reported the analysis of the coals with different rank. This study investigated the coal surface characteristics of the coals pretreated at different temperature using various analyses (BET, SEM, XPS, FT-IR), and this study can be the basis for other research and applications.     

An innovative modeling approach using Qual2K and HEC-RAS integration to assess the impact of tidal effect on River Water quality simulation

Water quality modeling has been shown to be a useful tool in strategic water quality management. The present study combines the Qual2K model with the HEC-RAS model to assess the water quality of a tidal river in northern Taiwan. The contaminant loadings of biochemical oxygen demand (BOD), ammonia nitrogen (NH₃-N), total phosphorus (TP), and sediment oxygen demand (SOD) are utilized in the Qual2K simulation. The HEC-RAS model is used to: (i) estimate the hydraulic constants for atmospheric re-aeration constant calculation; and (ii) calculate the water level profile variation to account for concentration changes as a result of tidal effect. The results show that HEC-RAS-assisted Qual2K simulations taking tidal effect into consideration produce water quality indices that, in general, agree with the monitoring data of the river. Comparisons of simulations with different combinations of contaminant loadings demonstrate that BOD is the most import contaminant. Streeter-Phelps simulation (in combination with HEC-RAS) is also performed for comparison, and the results show excellent agreement with the observed data. This paper is the first report of the innovative use of a combination of the HEC-RAS model and the Qual2K model (or Streeter-Phelps equation) to simulate water quality in a tidal river. The combination is shown to provide an alternative for water quality simulation of a tidal river when available dynamic-monitoring data are insufficient to assess the tidal effect of the river.     

Prenatal diagnosis of Hb H disease due to compound heterozygosity for South-East Asian deletion and Hb constant spring by polymerase chain reaction

A pregnant woman has two children affected by moderately severe Hb H disease due to compound heterozygosity of South-east Asian deletion and Constant Spring mutation. In her third pregnancy, transabdominal chorionic villus sampling was performed at the tenth gestational week to obtain fetal DNA. The polymerase chain reaction was used for detection of both the South-east Asian deletion and the Constant Spring mutation. Hb H disease was diagnosed in the fetus. After genetic counselling, the couple elected to have the pregnancy terminated.     

Microbial phytotoxins as potential herbicides

Abstract

Microbes are sources of a diverse array of phytotoxic compounds. These compounds are generally structurally different from commercial herbicides, targeting different molecular sites of action within the plant. These novel structures and sites can be excellent leads for the discovery and development of safer synthetic herbicides. Microbial phytotoxins are often more environmentally benign than synthetic herbicides. Examples of phytotoxins from fungi (AAL‐toxin, cornexistin, cyperin, and tentoxin) with novel structures and sites of action are discussed. AAL‐toxin is toxic to a wide variety of weeds at very low dose rates. AAL‐toxin and many of its analogues kill plants by inhibiting a ceramide synthase‐like enzyme, causing rapid accumulation of free sphingoid bases that disrupt membranes. Cornexistin appears to be metabolically cnverted to an inhibitor of certain aspartate amino transferase isoenzymes. Its activity can be reversed by feeding aspartate and glutamate or with tricarboxylic acid cycle intermediates. Its activity is much like that of (aminooxy)acetate. Cyperin is a diphenylether phytotoxin that inhibits protoporphyrinogen oxidase, but does not kill plants by this mechanism. It appears to have other effects on porphyrin metabolism. Tentoxin is toxic by two mechanisms. It disrupts chloroplast development by inhibiting the processing of a nuclear‐coded plastid protein, and it also inhibits photophosphorylation by acting as an energy transfer inhibitor of coupling factor 1 ATPase. Other examples of phytotoxins from microbes with promise as herbicides will be mentioned.     

The environmental effects of salinity load in Great Menderes Basin irrigation schemes

This study aimed to assess how poor planning for irrigation led to heavy salt loads, how those salt loads adversely affected the environment, and how to identify management practices to deal with these potential problems in the Great Menderes River Basin, Aydin Plain Irrigation Scheme of Turkey for the period between 2000 and 2006. In order to determine the effects on the environment; electrical conductivity, salinity load, total amount of water table salinity, inflow and outflow salinity were measured and calculated for the research area. There was no problem on account of water table fluctuations. The mean of area prevented the plant growth by high water table was 8.5%. The percentage of the area occurring water table salinity problem was 39.2. The total amount of salt transported to the Great Menderes River and accumulated in the soil of the research area was 211,609 and 246,565 tones respectively. Salt, 458,174 tones in total, had adverse effects on the environment.     

Reusing pretreated desulfurization slag to improve clinkerization and clinker grindability for energy conservation in cement manufacture

The purpose of this study was to combine the physical pretreatments of grinding, sieving, and magnetic-separation processes to reclaim iron-rich materials from the desulfurization slag, and to use the remainder for cement clinker production. The iron-rich materials can be separated out efficiently by grinding for 30 min and sieving with a 0.3 mm mesh. The non-magnetic fraction of the particles smaller than 0.3 mm was in the majority, and proved to be suitable for use as a cement raw material. The raw mixes prepared with a pretreated desulfurization slag had a relatively high reactivity, and the temperature at which alite forms was significantly reduced during the clinkerization process. The clinkers produced with 10% desulfurization slag had a high level of alite and good grindability. Generally, the improvements in clinkerization and clinker grindability are beneficial to energy conservation in cement manufacture.     

Environmental assessment of polycyclic aromatic hydrocarbons in the surface sediments of a remote region on the eastern coast,Taiwan

Surface sediment samples were collected in He-Ping Harbor and the nearby He-Ping Estuary from 2005 to 2006 to examine spatial and temporal variability in polycyclic aromatic hydrocarbon (PAH) concentrations. The sum of the 16 USEPA priority pollutant PAHs varied from 8 to 312 ng/g dry weight, which was relatively low compared to values obtained from other studies in the world. Regarding temporal changes in the PAH profile, total PAH concentrations in the wet season were lower than during the dry season in He-Ping Harbor. However, the concentration of PAHs exhibited no significant difference in the four seasons in the He-Ping Estuary. PAH concentrations in He-Ping Harbor were higher than those in the He-Ping Estuary. In comparison with sediment quality guidelines, PAH concentrations of sediments in this study were lower than those outlined in the criteria, which suggests no evident adverse biological effects due to PAHs around the He-Ping coast. Ratios of specific PAH compounds calculated to assess the possible sources of PAHs reflect that PAHs in He-Ping Harbor may mainly be from pyrogenic coal combustion.     

Feasibility of producing ethanol from food waste

Food waste generated in Korea is rich in carbohydrate as high as 65% of total solids. Using the food waste, the feasibility of ethanol production was investigated in a lab-scale fermentor. Pretreatment with hydrolyzing enzymes including carbohydrase, glucoamylase, cellulase and protease were tested for hydrolysis of food waste. The carbohydrase was able to hydrolyze and produce glucose with a glucose yield of 0.63 g glucose/g total solid. Enzymatic hydrolysis and ethanol fermentation by using carbohydrase and Saccharomyces cerevisiae were conducted in the batch mode. For separated hydrolysis and fermentation (SHF), ethanol concentration reached at the level corresponding to an ethanol yield of 0.43 g ethanol/g total solids. For simultaneous saccharification and fermentation (SSF), the ethanol yield was 0.31 g ethanol/g total solids. During the continuous operation of SHF, the volumetric ethanol production rate was 1.18 g/lh with an ethanol yield of 0.3g ethanol/g total solids. For SSF process, the volumetric ethanol production rate was 0.8 g/lh with an ethanol yield of 0.2g ethanol/g total solids.