Abstract  Acetylene, C2H2, is a highly reactive, commercially important hydrocarbon. Its reactivity is related to its triple bond between carbon atoms and, as a consequence, its high positive free energy of formation. Because of its explosive nature, long distance shipping or pressurized storage is not recommended. Thus acetylene is generally used as it is produced without shipping or storage. Commercially, acetylene is used primarily as a raw material for the synthesis of a variety of organic chemicals. In the United States, this accounts for ∼90% of acetylene usage, with the balance being used for metal welding and cutting. Worldwide acetylene production peaked in the mid-1960s, after which it declined dramatically as processes were developed to substitute lower cost olefins and paraffins for the acetylene feedstock. 1,4-Butanediol production accounts for 90% of the demand for acetylene for chemical production. Although acetylene production in Japan, China, and Eastern Europe is still based on the calcium carbide process, the large producers in the United States, Western Europe, and Russia now rely principally on the partial oxidation of natural gas. However, much of the incremental growth in production is based on producing acetylene as a coproduct of ethylene in the steam cracking process. As a coproduct, acetylene is much less costly than as produced from partial oxidation or calcium carbide.

Abstract  Chronic ethanol intoxication in rats accelerated the rate of ethanol metabolism, but decreased the activity of alcohol dehydrogenase. Chronic consumption of ethanol decreased the activities of cytochrome oxidase and succinic dehydrogenase in mitochondria and in cell-free homogenates, whereas total hepatic mitochondrial protein was not altered by ethanol feeding. Thus, total "mitochondrial activity" was decreased and cannot account for the increased rate of blood ethanol elearance. We therefore investigated the activities of mitochondrial enzymes and those of "shuttle" systems for the transport of reducing equivalents into mitochondria. Reconstituted malate-aspartate, fatty acid, and α-glycerophosphate shuttles were equally effective in transporting reducing equivalents into the mitochondria from ethanol-fed and control rats. The activities of enzymes involved in the shuttles, such as cytoplasmic and mitochondrial α-glycerophosphate dehydrogenase and glutamic oxalacetic transaminase, were either decreased or unchanged by chronic ethanol consumption. The permeability of the mitochondria to NADH and to substrate anions which participate in the shuttles was also not altered by ethanol feeding. It is therefore unlikely that the increased rates of ethanol oxidation produced by chronic ethanol consumption are caused by enhanced transport of reducing equivalents into the mitochondria. A high fat diet alone (35% of total calories) increased both the endogenous and total rates of shuttle activity, compared with the rates obtained with mitochondria from rats which had consumed a low fat diet. However, the rates of blood ethanol clearance were comparable in rats consuming high fat and low fat diets. Therefore, the transport of reducing equivalents into the mitochondria under these conditions does not appear to be rate-limiting for ethanol metabolism.

Abstract  The early ultrastructural changes induced by isocaloric substitution of ethanol for carbohydrate in the livers of 2 human subjects were studied. Mitochondrial alterations and focal cytoplasmic degradation were noted within 1 day of the full dose of ethanol (46 % of total calories), at a time when fat accumulation was minimal. Fatty metamorphosis was prominent within 3 to 10 days of the full dose of ethanol and was associated with alterations of mitochondria, endoplasmic reticulum, autophagic vacuoles, microbodies, and ductular cells. It is concluded that alcohol exerts a direct toxic action on the liver which precedes or is concomitant with fatty metamorphosis.

Abstract  The homeobox, a 60-amino acid-encoding DNA sequence, originally discovered in the genome of the fruit fly Drosophila, was subsequently identified throughout the three kingdoms of multicellular organisms. Homeobox-containing genes encode DNA-binding proteins that regulate gene expression and control various aspects of morphogenesis and cell differentiation. In particular, the Hox family of clustered homeobox genes plays a fundamental role in the morphogenesis of the vertebrate embryo, providing cells with regional information along the main body axis. The nonclustered or divergent homeobox genes include a large number of genes scattered throughout the genome that, nevertheless, can be organized in distinct families based on their homologies and functional similarities. This review will provide the reader with a brief overview on some recent studies aimed at understanding the functional role of homeobox genes in normal mammalian development as well as their involvement in congenital malformations and oncogenesis.

Abstract  Background: Metabolomic studies have been applied to disease biomarkers selection. With the metabolomic technique, gas chromatography/mass spectrometry (GC/MS), human serum metabolites can be detected and identified. The purpose of this study was to investigate the serum metabolic profile of hepatitis B virus (HBV) infected cirrhosis patients and to detect disease biomarkers. Methods: HBV infected non-cirrhosis male subjects (n=20) and HBV infected cirrhosis male patients (n=20) participated in this experiment. Serum metabolome was detected through chemical derivatization followed by GC/MS. The high-flux metabolomic data were analyzed by stepwise discriminant analysis. Results: Out of the 41 metabolites detected in serum, we selected metabolites, including acetic acid, sorbitol, D-lactic acid, hexanoic acid, 1-naphthalenamine, butanoic acid, phosphoric acid, D-glucitol, and glucose, which in combination with each other could segregate the two groups. The error count was 0% for the non-cirrhosis group and 25% for the cirrhosis group. Conclusions: This technique can be used to select biomarkers for hepatic cirrhosis. Clin Chem Lab Med 2009;47.

Abstract  Tertiary butyl alcohol (TBA) was administered to groups of 15 female B6C3F1 mice in drinking water at concentrations of 0, 2.0 or 20 mg TBA ml(-1), for 14 days, for assessment of gross and histological changes in the liver and thyroid, thyroid hormones (T3, T4, and TSH), total hepatic cytochrome P450 (Cyp) content, specific Cyp activities and quantitative PCR analysis of specific Cyp enzymes (Cyp1a1, Cyp2b9, Cyp2b10, Cyp3a11), sulfuryltransferases (ST1a1, ST2a2, and STn) and glucuronyltransferases (UGT1a1, UGT2b1, and UGT2b5). Phenobarbital (PB) was administered to a positive control group by oral gavage at a daily dose of 80 mg kg(-1). TBA caused, on day 14, a reduction in circulating T3 (12-15% decrease) and a dose-dependent reduction in T4 (13-22% decrease), with no evidence of thyroid pathology. Two of five livers examined in the 20 mg TBA ml(-1) dose group showed mild, diffuse centrilobular hypertrophy. On day 14, Cyp 7-benzoxyresorufin-O-debenzylase activity was significantly induced 12-fold by TBA at 20 mg ml(-1), and 1.8-fold at the 2.0 mg TBA ml(-1) concentration. Cyp 7-pentoxyresorufin-O-dealkylase activity was slightly induced (2.1-fold) by 20 mg TBA ml(-1) on day 14. Quantitative PCR analysis of gene transcripts showed a significant induction of Cyp2b10 and ST1a1 with both TBA concentrations, and a slight induction of Cyp2b9 at 20 mg TBA ml(-1) only. PB induced all phase I and phase II gene transcripts except for Cyp1a1 and Cyp2b9. These findings suggest that TBA, at and below doses used in chronic studies, is an inducer of phase I and phase II liver enzymes, with resulting decreases in circulating thyroid hormones in B6C3F1 mice.

Abstract  Low-temperature nonthermal plasma has been used to prepare solid-phase microextraction (SPME) fibers with high adsorbability. long-term serviceability, and high reproducibility. Graphite rods serving as fiber precursors were treated by an air plasma discharged at 15.2-15.5 kV for a duration of 8 min. Sampling results revealed that the adsorptive capacity of the homemade fiber was 2,5-34.6 times that of a polyacrylate (PA) fiber for alcohols (methanol, ethanol, isopropyl alcohol, n-butyl alcohol), and about 1.4-1.6 times and 2.5-5.1 times that of an activated carbon fiber(ACF) for alcohols and BTEX (benzene, toluene, ethylbenzene, and xylenes), respectively. It is confirmed from FTIR (Fourier transform infrared spectrophotometer) and SEM (scanning electron microscope) analyses that the improvement in the adsorptive performance attributed to increased Surface energy and toughness of the graphite fiber. Using gas chromatography (GC)-flame-ionization detector (FID), the limits of detection (LODs) of the alcohols and BTEX ranged between 0.19 and 3.75 mu g L-1, the linear ranges were between 0.6 and 35619 mu g L-1 with good linearity (R-2 =0.9964-0.9997). it was demonstrated that nonthermal plasma offers a fast and simple method for preparing an efficient graphite SPME fiber, and that SPME using the homemade fiber represents a sensitive and selective extraction method for the analysis of a wide range of organic compounds. (C) 2008 Elsevier B.V. All rights reserved.

Abstract  Abstract: In this paper, we evaluate the efficiency of UV/H2O2 process to remove methyl tert-butyl ether (MtBE) and tertiary butyl alcohol (tBA) from a drinking water source. Kinetic models were used to evaluate the removal efficiency of the UV/H2O2 technologies with different pretreatment options and light sources. Two commercial UV light sources, i.e. low pressure, high intensity lamps and medium pressure, high intensity lamps, were evaluated. The following pretreatment alternatives were evaluated: (1) ion exchange softening with seawater regeneration (NaIX); (2) Pellet Softening; (3) weak acid ion exchange (WAIX); and (4) high pH lime softening followed by reverse osmosis (RO). The presence or absence of a dealkalization step prior to the UV/H2O2 Advanced Oxidation Process (AOP) was also evaluated for each pretreatment possibility. Pretreatment has a significant impact on the performance of UV/H2O2 process. The NaIX with dealkalization was shown to be the most cost effective. The electrical energy per order (EEO) values for MtBE and tBA using low pressure high output UV lamps (LPUV) and 10mg/LH2O2 are 0.77 and 3.0kWh/kgal-order, or 0.20 and 0.79kWh/m³-order, respectively. For medium pressure UV high output lamps (MPUV), EEO values for MtBE and tBA are 4.6 and 15kWh/kgal-order, or 1.2 and 4.0kWh/m³-order, for the same H2O2 dosage. [Copyright 2008 Elsevier] Copyright of Water Research is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts)

Abstract  This paper presents formaldehyde and volatile organic compounds (VOC) concentrations, potential sources and impact factors in 100 homes. The 24-h average formaldehyde concentration in 37 homes exceeded the good class of the Hong Kong Indoor Air Quality Objectives (HKIAQO), whereas the total VOCs concentration in all homes was lower than the HKIAQO. Compared to other East Asian cities, indoor formaldehyde and styrene in Hong Kong was the highest, reflecting that the homes in Hong Kong were more affected by household products and materials. The formaldehyde concentration in newly built apartments was significantly higher than that in old buildings, whereas no relationship between the concentration and the building age was found for VOCs. There was no difference for formaldehyde and toluene between smoking and non-smoking homes, suggesting that cigarette smoking was not the major source of these two species. Homes of a couple with a child had higher formaldehyde and acetic acid concentrations, while homes with more than three people had higher concentrations of 1-butanol, heptane and d-limonene. When shoes were inside the homes, heptane, acetic acid, nonane and styrene concentrations were statistically higher than that when shoes were out of the homes. Furthermore, higher levels of 1,2,4-trimethylbenzene, styrene, nonane and heptane were found in gas-use families rather than in electricity-use homes. PRACTICAL IMPLICATIONS: Long-term exposure to formaldehyde and volatile organic compounds (VOC) in indoor environments may cause a number of adverse health effects such as asthma, dizziness, respiratory and lung diseases, and even cancers. Therefore, it is critical to minimize indoor air pollution caused by formaldehyde and VOCs. The findings obtained in this study would significantly enhance our understanding on the levels, emission sources and factors which affect indoor concentrations of formaldehyde and VOCs. The results can help housing designers, builders, home residents, and housing department of the government to improve indoor air quality (IAQ) by means of appropriate building materials, clean household products and proper life styles. It can also help policy makers reconcile the IAQ objectives and guidelines.

Abstract  Alcohols are widely used as industrial solvents. In spite of the fact that ethanol is a human teratogen, there has not been systematic investigation of the potential teratogenic effects of other alcohols, particularly using the inhalation route of exposure, as would be appropriate in assessing occupational and environmental types of experience. As part of a large teratological examination of industrial alcohols, methanol and ethanol were administered by inhalation to groups of approximately 15 pregnant Sprague-Dawley rats. Methanol was administered at 20,000 ppm (20ME), 10,000 ppm (10ME), 5000 ppm (5ME), and 0 ppm (MECO) for 7 hr/day on Days 1-19 of gestation (Days 7-15 for 20ME). Ethanol was administered at 20,000 ppm (20ET), 16,000 ppm (16ET), 10,000 ppm (10ET), and 0 ppm (ETCO) for 7 hr/day on Days 1-19 of gestation. Dams were sacrificed on Day 20 (sperm = Day 0). One-half of the fetuses were examined using the Wilson technique for visceral defects, and the other half were examined for skeletal defects. The highest concentration of methanol (20ME) produced slight maternal toxicity and a high incidence of congenital malformations (p less than 0.001), predominantly extra or rudimentary cervical ribs and urinary or cardiovascular defects. Similar malformations were seen in the 10ME group, but the incidence was not significantly different from controls. No adverse effects were noted in the 5ME group. Dams in the 20ET group were narcotized by the end of exposure, and maternal weight gain and feed intake were decreased during the first week of exposure. The 16ET dams had slightly depressed weight gain (p less than 0.01) during the first week of exposure, but there were no significant effects on feed consumption. There was no definite increase in malformations at any level of ethanol, although the incidence in the 20ET group was of borderline significance.

Abstract  Abstract: Prior studies have shown the effectiveness of Fenton reagent (FR) for degrading low concentrations (1.0–2.0mg/L) of methyl tert-butyl ether (MTBE), similar to those found in contaminated groundwater. The present study investigates the effect of increasing FR doses on the extent of degradation and mineralization of a given initial MTBE concentration. The FR to MTBE molar ratio (FMMR) was the operating variable, and was investigated at values between 0.5:1 and 200:1. This approach provided sequential snapshots of the MTBE degradation process, which may help to improve the understanding of MTBE degradation with FR. The initial MTBE concentration (MTBE0) was approximately 22.7μM (∼2.0mg/L), and FR was used in a 1:1 molar ratio of ferrous iron (Fe²⁺) and hydrogen peroxide (H2O2). The concentrations of MTBE and the following main reaction byproducts: tert-butyl formate (TBF), tert-butyl alcohol (TBA), acetone and methyl acetate were determined from samples collected at specific intervals over a total reaction time of 1h. Total organic carbon (TOC) was monitored to determine MTBE mineralization, and the total concentration of tert-butyl compounds (tBC) was monitored due to the suspected toxicity associated with this functional group. The results showed that the minimum FMMR necessary for achieving complete MTBE degradation was 20:1, but at that FMMR, TOC and tBC reduction were only 45.6% and 24.9%, respectively. Complete MTBE mineralization was not achieved in any case, even at FMMRs as high as 200:1, where only 63.3% of mineralization was observed (although tBC reduction reached 99.6%, since traces of TBA were still detected). These results confirm the relative inability of FR to achieve complete mineralization of a target substrate, even those that are highly reactive with the hydroxyl radical. [Copyright 2008 Elsevier] Copyright of Water Research is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts)

Abstract  Radix Tinosporae is a herb widely used in traditional Chinese medicine for the treatment of various inflammatory diseases. In the present study, its anti-inflammatory and antinociceptive activities were investigated. The ethanol extract of Radix Tinosporae exhibited significant inhibitory effects on xylene-induced ear edema and acetic acid-induced writhing in mice. Using bioassay-guided fractionation, the n-butanol fraction was determined as the active fraction. Further purification of the most active n-butanol fraction led to the isolation of three compounds, palmatine, columbamine and columbinyl glucoside. All three compounds showed inhibitory activities on xylene-induced ear edema, but only palmatine and columbamine exhibited significant inhibitory effects on acetic acid-induced writhing. In addition, palmatine and columbamine markedly inhibited in vitro production of nitric oxide and nuclear factor-kappaB activation in RAW264.7 macrophage cells in response to lipopolysaccharide or tumor necrosis factor alpha stimulation. These results provide justification for the utilization of Radix Tinosporae in Chinese folk medicine for the treatment of inflammatory diseases.

Abstract  Alpinia officinarum Hance (Zingiberaceae) is an annual plant. Its rhizome has long been used as an anti-inflammatory, an analgesic, a stomachic and a carminative in traditional medicine.

The aim of this study was to test the anti-inflammatory effects of Alpinia officinarum rhizomes on acute and chronic arthritis in SD rats.

Alpinia officinarum rhizomes were extracted by refluxing using 80% ethanol. The fractions were prepared by the fractionation of ethyl acetate (EtOAc), n-butanol, and water. This extract was administrated to rats by peroral injection. Acute arthritis was induced by a subcutaneous injection of carrageenan into the hind paw of SD rats. Chronic arthritis was stimulated by a subcutaneous injection of complete Freund's adjuvant (CFA) into the hind paw of SD rats. The paw volume was measured using a plethysmometer, thermal hyperalgesia was tested using a thermal plantar tester, hyperalgesia was evaluated by ankle flexion evoked vocalizations, and the expression of c-Fos in the brain hippocampus was measured with the avidin-biotin-peroxidase technique. Nitric oxide (NO) production was evaluated on nitrite by a Griess assay in lipopolysaccharide (LPS)-induced murine macrophage RAW 264.7 cells.

An 80% ethanolic extract showed acute anti-inflammatory activity that it reduced the edema volume in carrageenan-stimulated arthritis and inhibited NO generation in LPS-induced RAW 264.7 cells. In addition, this extract showed chronic anti-rheumatic and analgesic activities by suppressing the swelling volume, by recovering the paw withdrawal latency, and by inhibiting the flexion scores in CFA-induced arthritis. Particularly, this medicine had potent meaningful effects on the second signal of the left hind paw in the form of an immunological reaction compared to its effects on the first signal in the right hind paw after the CFA treatment. This also shows an anti-psychiatric effect through control of the expression of the c-Fos protein of the brain hippocampus in CFA-stimulated arthritis. On the other hand, each fraction showed acute anti-inflammatory effects; the action of the EtOAc fraction may have resulted from the suppression of NO production.

Alpinia officinarum rhizomes may be viable therapeutic or preventive candidates for the treatment of acute and chronic arthritis.

Abstract  The gut microflora in some patients with Crohn's disease can be reduced in numbers of butyrate-producing bacteria and this could result in metabolic stress in the colonocytes. Thus, we hypothesized that the short-chain fatty acid, butyrate, is important in the maintenance and regulation of the barrier function of the colonic epithelium.

Confluent monolayers of the human colon-derived T84 or HT-29 epithelial cell lines were exposed to dinitrophenol (DNP (0.1 mM), uncouples oxidative phosphorylation) + Escherichia coli (strain HB101, 10(6) cfu) +/- butyrate (3-50 mM). Transepithelial resistance (TER), and bacterial internalization and translocation were assessed over a 24-hour period. Epithelial ultrastructure was assessed by transmission electron microscopy.

Epithelia under metabolic stress display decreased TER and increased numbers of pseudopodia that is consistent with increased internalization and translocation of the E. coli. Butyrate (but not acetate) significantly reduced the bacterial translocation across DNP-treated epithelia but did not ameliorate the drop in TER in the DNP+E. coli exposed monolayers. Inhibition of bacterial transcytosis across metabolically stressed epithelia was associated with reduced I-kappaB phosphorylation and hence NF-kappaB activation.

Reduced butyrate-producing bacteria could result in increased epithelial permeability particularly in the context of concomitant exposure to another stimulus that reduces mitochondria function. We speculate that prebiotics, the substrate for butyrate synthesis, is a valuable prophylaxis in the regulation of epithelial permeability and could be of benefit in preventing relapses in IBD.

Abstract  Tert-Butanol is an important intermediate in industrial chemical synthesis, particularly of fuel oxygenates. Human exposure to tert-butanol may occur following fuel oxygenate metabolism or biodegradation. It is poorly absorbed through skin, but is rapidly absorbed upon inhalation or ingestion and distributed to tissues throughout the body. Elimination from blood is slower and the half-life increases with dose. It is largely metabolised by oxidation via 2-methyl-1,2-propanediol to 2-hydroxyisobutyrate, the dominant urinary metabolites. Conjugations also occur and acetone may be found in urine at high doses. The single-dose systemic toxicity of tert-butanol is low, but it is irritant to skin and eyes; high oral doses produce ataxia and hypoactivity and repeated exposure can induce dependence. Tert-Butanol is not definable as a genotoxin and has no effects specific for reproduction or development; developmental delay occurred only with marked maternal toxicity. Target organs for toxicity clearly identified are kidney in male rats and urinary bladder, particularly in males, of both rats and mice. Increased tumour incidences observed were renal tubule cell adenomas in male rats and thyroid follicular cell adenomas in female mice and, non-significantly, at an intermediate dose in male mice. The renal adenomas were associated with α2u-globulin nephropathy and, to a lesser extent, exacerbation of chronic progressive nephropathy. Neither of these modes of action can function in humans. The thyroid tumour response could be strain-specific. No thyroid toxicity was observed and a study of hepatic gene expression and enzyme induction and thyroid hormone status has suggested a possible mode of action.

Abstract  Cyclotrimethylenetrinitramine (RDX) has been used extensively as an explosive. Prior to this study no data were available on the metabolism of RDX in animals. Metabolism of 14C-RDX was studied in male and female miniature pigs after a one-time gavage with 41 to 44 mg/kg, (0.8 to 0.9 mCi/animal) in an aqueous suspension of 0.1% carboxymethyl cellulose. Metabolic profiles and identification of 14C-RDX-derived radioactivity in plasma, liver and urine were performed utilizing HPLC radio-scanning and LC/MS/MS analysis. Analytical standards were available for all proposed metabolites. Two HPLC columns with differing elution profiles were used for separation, quantification and tentative identification. Identifications were confirmed using LC/MS/MS. Two metabolites were isolated and identified as 4-nitro-2, 4-diazabutanal and a novel metabolite, 4-nitro- 2-4 diaza-butanamide. Analysis also revealed trace levels of 1-nitroso-3,5-dinitro-1,3,5-triazacyclohexane (MNX), 1,3-dintroso-5-nitro-1,3,5-triazacyclohexane (DNX) and 1,3,5-trinitroso- 1,3,5-triazacyclohexane (TNX) in plasma and showed trace levels of MNX and DNX in urine. No metabolites were detected in the liver samples. Thus RDX was metabolized primarily by a method that accomplished both denitration and oxidative cleavage of the ring structure of this compound to form butanal and butanamide metabolites.

Abstract  This work proposed a gas sensor for the determination of tert-butyl mercaptan, one of the highly toxic volatile sulfur compounds, which was based on cataluminescence emission during its catalytic oxidation on the surface of nanosized V(2)O(5). The cataluminescence characteristics and the optimum conditions, including the morphology of sensing material, the wavelength of cataluminescence emission, the oxygen flow rate and working temperature were investigated in detail. Under the optimized conditions, the calibration curve of the relative cataluminescence intensity versus the concentration of tert-butyl mercaptan vapor was made, with the linear range of 5.6-196 microg mL(-1) and the detection limit of 0.5 microg mL(-1) (S/N=3). The relative standard deviation (R.S.D.) (n=5) of relative cataluminescence intensity for 84 microg mL(-1) tert-butyl mercaptan was 3.6%. There is no or weak response to some common substances, such as formic acid, alcohol (methanol, ethanol, propanol, isopropanol, n-butanol, isoamyl alcohol), o-dichlorobenzene, acetonitrile, ethyl acetate, aldehyde (formaldehyde, acetaldehyde and propanal), 1,2-dichloroethane and ammonia. Furthermore, the proposed sensor was successfully used for determining tert-butyl mercaptan in four artificial samples, with a good recovery. The results demonstrated that the proposed gas sensor had a promising capability for the tert-butyl mercaptan in routine monitoring.

Abstract  Monoclinic monazite-type EuPO4 and LaPO4:Eu nanorods were synthesized by a microemulsion-assisted solvothermal method. Their morphologies, structures, and fluorescent properties were characterized by SEM, XRD, and photoluminescence (PL) modern analytic means, respectively. The aspect ratios of EuPO4 and LaPO4:Eu nanorods have a decreasing tendency with increasing carbon chain length of assisted surfactants. When the assisted surfactant was n-butyl alcohol, the EuPO4 exhibited nanorod morphology with diameters from 20 to 30 nm and lengths from 100 to 150 nm. When the assisted surfactant was n-pentanol, the EuPO4 nanorods had lengths between 200 and 300 nm and a diameter range similar to that of the n-butyl alcohol nanorods. When the assisted surfactant was n-hexanol and n-octyl alcohol, only elliptical EuPO4 products were obtained. The LaPO4:Eu nanorods synthesized in the presence of different assisted-surfactants exhibited elliptical morphologies with diameters of 40-60 nm and lengths of 70-110 nm. The LaPO4:Eu and EuPO4 nanorods showed a orange prominent emission peak from magnetic-dipole transition 5D0 --> F1 (593 nm) of Eu3+ ions whose sites in the EuPO4 and LaPO4:Eu nanorods have C1 symmetry. Compared with bulk LaPO4:Eu, the fine structure of the Eu-O charge transfer band has very small red shift resulting from the slight increase of the length of Eu-O bond due to nanoscale size effect.

Abstract  In experiments with the atomization of n-butyl acetate in chambers with rats, the LC50 was as low as 156 ppm.(4) However, workplace exposures occur almost universally to n-butyl acetate vapor, and direct exposure to atomized n-butyl acetate exposure did not occur in occupational situations.^ Accordingly, the marked toxicity of the atomized n-butyl acetate observed in animal bioassays is not of practical concern in the workplace. A TLV-TWA of 150 ppm is recommended for n-butyl acetate to minimize the potential risk of eye and mucous membrane irritation reported in volunteers exposed at 200 to 300 ppm of n-butyl acetate for 3 to 20 minutes.(35,37) A TLV-STEL of 200 ppm is recommended to control the excursions that produced mucous membrane irritation in the volunteers at exposures of 200 to 300 ppm for 3 to 20 minutes.(35,37) Given the high vapor pressure of this compound and the fact that topical application of n-butyl acetate in rabbits(27) and guinea pigs(20) failed to elicit systemic toxicity, the skin notation is not warranted Sufficient data were not available to recommend SEN or carcinogenicity notations. The reader is expected to be familiar with the section on Excursion Limits in the "Introduction to the Chemical Substance TLVs" of the current edition of the Documentation of the TLVs and BEIs for the guidance and control of excursions above the TLV-TWA, even when the 8-hour TWA is within the recommended limit.

Abstract  This experimental study deals with the colloidal stability of sterically functionalized magnetite nanoparticles in a low dielectric constant organic solvent with different concentrations of technical grade polymers. Those dispersions are the starting point of a solution and spray drying process chain to synthesize highly filled nanocomposite materials with nanoparticle volume concentrations exceeding 10%. We introduce a thermo gravimetric method together with light extinction and dynamic light scattering measurements to gain quantitative information on the concentration of primary particles and the mechanism of destabilization or stabilization by polymer addition. Poly(vinyl butyral) is found to stabilize the dispersion considerably caused by stronger interactions with the fatty acid coated magnetite particles quantified by means of adsorption measurements. Both poly(methyl methacrylate) as well as two grades of poly(bisphenol A carbonate) are found to destabilize the dispersion due to depletion flocculation over the entire concentration range investigated However there is a significant quantity of a stable fraction of primary nanoparticles in the supernatant after depletion flocculation occurred. This fraction of primary particles is increasing with decreasing polymer concentration. We furthermore point out important concerns and limitations for the composition of and concentrations in such complex colloidal systems for use in industrially relevant processes.

Abstract  Titanate sol-gel layers imprinted with carbonic acids were used as sensitive layers on quartz crystal microbalance. These functionalized ceramics enable us detection of volatile organic compounds such as ethanol, n-propanol, n-butanol, n-hexane, n-heptane, n-/iso-octane, and n-decane. Variation of the precursors (i.e., tetrabutoxy titanium, tetrapropoxy titanium, tetraethoxy titanium) allows us to tune the sensitivity of the material by a factor of 7. Sensitivity as a function of precursors leads to selective inclusion of n-butanol vapors down to 1 ppm. The selectivity of materials is optimized to differentiate between isomers, e.g., n- and iso-octane. The results can be rationalized by correlating the sensor effects of hydrocarbons with the Wiener index. A mass-sensitive sensor based on titanate layer was also developed for monitoring emanation of degraded engine oil. Heating the sensor by a meander avoids vapor condensation. Thus, a continuously working oil quality sensor was designed.

Abstract  1. Human alcohol dehydrogenase (ADH) has been investigated by spectrophotometry assay and by starch-gel electrophoresis. 2. Assays were carried out at pH 8-8 and pH 11-0 on liver samples obtained post mortem from 129 adults over the age of 20, 37 premature infants and infants less than one year old and 56 foetuses. Sixteen cases of the previously described atypical pH ratio phenotype were identified among the 166 adults and infants tested. No examples of the atypical pH ratio phenotype were encountered among the foetuses. On average the foetal liver ADH activity was less than in adults and it appeared to increase with increasing gestational age. 3. Electrophoretic analyses of ADH in liver samples obtained from 117 foetuses of various gestational ages, 62 premature infants and infants less than a year old and a group of more than 200 adults over the age of 20, indicate that developmental changes occur during intrauterine life. 4. The atypical pH ratio phenotype liver ADH isozyme pattern was found to be electro-phoretically different from that of the usual pH ratio phenotype. 5. The ADH isozyme pattern in lung tissue was the same in adults, infants and foetuses. The overall activity was low and mainly concentrated in a single isozyme which was electrophoretic-ally indistinguishable from the main ADH isozyme of adult liver. Usual and atypical pH ratio phenotypes were identified, both by assay and by starch-gel electrophoresis, in foetal, infant and adult lung specimens. 6. The ADH activity of kidney and intestine was too weak for assay with ethanol as substrate. In adults the isozyme patterns in kidney were similar to those found in adult liver. In foetal intestine and kidney, however, the ADH isozymes were quite different from those of adult liver and also foetal liver. Three distinct phenotypes, designated ADH3 1, ADH3 2-1 and ADH3 2, were recognized in foetal kidney and intestine, occurring with frequencies of 0–42, 0–42, and 0–16 respectively in a survey of 117 specimens. 7. The appearance of the ADH isozyme patterns in liver and in foetal kidney and intestine is consistent with the hypothesis that ADH has a dimeric sub unit structure. 8. The findings suggest that at least three autosomal gene loci may be concerned in determining the structure of alcohol dehydrogenase in man. (a) Locus ADH1primarily active in the liver in early foetal life, becoming less active during gestation and only weakly active during adult life. (b) Locus ADH2 (i) expressed in lung in early foetal life and remaining active in this tissue throughout life, (ii) active in liver after about the first trimester and gradually becoming more active so that in adults this locus is responsible for most of the liver ADH activity, (iii) also active in adult kidney, (iv) the atypical pH ratio phenotype is probably determined by a variant allele at the ADH2 locus. (c) Locus ADH3- active during foetal and early post-natal life in intestine and kidney. The variant phenotypes ADH3 1, ADH3 2-1 and ADH3 2 are thought to represent the genotypes ADH13ADH31,ADH32ADH32 and ADE31ADH32 respectively, where ADH31 and ADH32 are alleles at the ADH3 locus. The gene-frequency estimate of ADH31 is 0.63 and of ADH32 is 0.37.