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31.
Journal of Material Cycles and Waste Management - Arsenic (As), selenium (Se), and chromium (Cr) are harmful to humans at certain concentrations, and can possibly be eluted from coal ash (fly ash)...  相似文献   
32.
Buckwheat tea waste (BWTW) and barley tea waste (BTW), by-products of the beverage industry, are alternative carbohydrate sources for ethanol production. In this study, optimal enzyme loading for enzymatic saccharification of BWTW and BTW was determined, and simultaneous saccharification and fermentation (SSF) was performed by Saccharomyces cerevisiae and Mucor indicus to produce ethanol. Optimal enzyme loading for enzymatic saccharification of 2?% w/v BWTW and BTW was 0.5?% (weight of enzyme/weight of tea wastes) for BWTW and 0.1?% for BTW. Ethanol production from BWTW by S. cerevisiae and M. indicus after 48?h of SSF was 49.9/100?g of BWTW and 47.9/100?g of BWTW, respectively, with 0.5?% enzyme loading. Ethanol production from BTW by S. cerevisiae and M. indicus after 48?h of SSF was 20.5/100?g of BTW and 21.6/100?g of BTW, corresponding to 62 and 66?% of the theoretical yield based on starch content, respectively, with 0.1?% of enzyme loading. Furthermore, S. cerevisiae produced 76?% of the theoretical yield based on the total glucose from starch in BWTW and BTW when a mixture of BWTW and BTW was used as a substrate, with 0.2?% enzyme loading and no additional nitrogen or mineral sources.  相似文献   
33.
After packing a compact of coal fly ash mixed with 3.5?M (mol/L) sodium hydroxide solution into a cylindrical plastic mold at 80?°C and 50?% relative humidity for 24?h, the plastic mold was released and the compact was immersed in 3.5?M sodium hydroxide solution at 80?°C for 48?h. When the resultant compact was removed from the solution and cured at 80?°C and 50?% relative humidity for 7?days, a bulk material with zeolite was formed. The strength of the resultant bulk material was a result of the formation of geopolymer (alkali-activated cement). The specific surface area and the compressive strength of the bulk body sample were 21.4?m2/g and 29.0?MPa, respectively. According to a quantitative analysis conducted using the X-ray diffraction (XRD) technique, the content of the formed Na-P type zeolite was estimated to be approximately 28.2?% in mass ratio. The pore size of the resultant bulk materials with zeolite ranges from sub-nanometer to several tens of nanometers, so the resultant bulk material with zeolite exhibited excellent water vapor retention characteristics.  相似文献   
34.
Journal of Material Cycles and Waste Management - Smelting of copper, a crucially important resource, releases small amounts of mercury into the atmosphere, thereby endangering people and the...  相似文献   
35.
Grass puffer Fugu niphobles, captured in November 1986 at Shimoda, Japan, and then reared at different temperatures ranging from 10 to 29°C, was examined for microflora changes in the skin, gill and intestines. At 10°C, the skin and gill were colonized mainly by Pseudomonas, Flavobacterium and Moraxella, while at 29°C Vibrio and Flavobacterium appeared abundantly. The intestinal microflora, consisting of Vibrio, Pseudomonas and Flavobacterium, revealed little temperature dependence, although the intrageneric composition of Vibrio changed conspicuously depending on the change of water temperature. Vibrio group 1, tentatively identified as V. alginolyticus, was detected in all tissues examined at 20 and 29°C. This, along with the fact that V. alginolyticus produces tetrodotoxin, suggests that the tetrodotoxin contained in puffer is, at least partly, accounted for by this bacterial species inhabiting intestines.  相似文献   
36.
37.
The amounts of enzyme proteins of peroxisomal β-oxidation in fibroblasts and chorionic villous cells from infants with Zellweger syndrome and in fibroblasts, amniocytes, and chorionic villi from healthy controls were measured by immunoblot analysis. Immunoreactive proteins of peroxisomal acyl-CoA oxidase and 3-ketoacyl-CoA thiolase were absent in fibroblasts and chorionic villous cells from the patients, yet these enzyme proteins were present in fibroblasts, cultured amniocytes, and chorionic villi from the normal controls. These results show that immunoblot analysis of peroxisomal β-oxidation enzymes in amniocytes and chorionic villous cells is of potential value for the prenatal detection of Zellweger syndrome.  相似文献   
38.
The influence of nutrient deprivation on cell-cycle progression was examined in two phytoplankton species, the diatom Thalassiosira weissflogii (actin) and the coccolithophorid Hymenomonas carterae (cocco II). The diatom was starved for nitrogen, silicon or both, whereas only nitrogen limitation was examined in H. carterae. In both species, nitrogen-starved cells were arrested in the early part of the cell cycle (G1 phase). In the diatom, silicon-starvation arrested cells in late G1 phase and also in the last part of the cell cycle (G2+M). In all cases, cell-cycle arrest could be reversed by addition of fresh medium, but cell-cycling times during the first generation were increased in comparison to those in nutrient replete, steady-state growth conditions. These results supply evidence for simultaneous dual-nutrient limitation of population growth and provide a mechanistic interpretation for the division patterns observed in cultures where nutrients are supplied periodically.  相似文献   
39.
Two starfishes, togemomijigai Astropecten polyacanthus and momijigai A. scoparius were collected from the Seto Inland Sea in October 1983 through November 1984, and assayed for toxicity by the standard method for tetrodotoxin (TTX). Most of the 54 A. polyacanthus specimens assayed were toxic, with the highest toxicity score being 520 mouse units (MU) g-1. All seven A. scoparius were toxic, with the highest score being 46 MU g-1. The toxin from A. polyacanthus was purified by a method which consisted mainly of activated charcoal treatment, and chromatography on CM-Sephadex C-25 and Bio-Rex 70 columns. The purified starfish toxin showed a specific toxicity of 4 700 MU mg-1, a value which was almost comparable to that of authentic TTX. From the thin-layer chromatographic and electrophoretic behavior, along with 1H-NMR spectrum, A. polyacanthus toxin was identified as TTX.  相似文献   
40.
A ring test by 19 labolatories in Japan was carried out in 1984 for the evaluation of the experimental manuals for the measurements of water solubility and partition coefficient (n-octanol/water). The experimental data obtained by the procedures in the manuals were collected by Environmental Agency, Japan. In the measurement of water solubility, this manual applies a modified batch method (the glass beads technique), whereas the OECD Test Guidelines suggests the use of the column elution method for chemicals having water solubility lower than 10 mg/L. Anthracene and flouranthene were used as test chemicals for the measurement of water solubility, and γ -hexachlorocyclohexane (γ -HCH) and 1,2,3-trichlorobenzene were used for partition coefficient. Good agreements were observed at a practical basis between the OECD methods and our methods for the results of mesurements of water solubility and partition coefficient. We concluded that the present ring test showed an advantage of the use of the glass beads method which requires only simple apparatus in water solubility measurement, and the HPLC method is very useful to measure partition coefficient because of the simplicity of procedure and the wide range of measurement, especially at higher values of partition coefficient.  相似文献   
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