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PubMed2006

Distillation kinetics of solid mixtures of hydrogen peroxide and water and the isolation of pure hydrogen peroxide in ultrahigh vacuum.

We present results of the growth of thin films of crystalline H2O2 and H2O2*2H2O (dihydrate) in ultrahigh vacuum by distilling an aqueous solution of hydrogen peroxide. We traced the process using infrared reflectance spectroscopy, mass loss on a quartz crystal microbalance, and in a few cases ultraviolet-visible reflectance. We find that the different crystalline phases-water, dihydrate, and hydrogen peroxide-have very different sublimation rates, making distillation efficient to isolate the less volatile component, crystalline H2O2.

Journal Article↗

PubMed1966

The incorporation of [1-14C] acetate into the methyl ketones that occur in steam-distillates of bovine milk fat.

1. The (14)C-labelling of the fatty acids and the methyl ketones in steam-distillates of milk fat from a lactating cow that had been injected intravenously with [1-(14)C]acetate was determined. 2. The labelling patterns of the C(6)-C(16) fatty acids and the corresponding methyl ketones with one fewer carbon atoms were similar, particularly so for the C(5)-C(10) compounds at 9 and 22hr. after the injection of [1-(14)C]acetate. The isolation of (14)C-labelled methyl ketones in the range C(3)-C(15) is evidence that the beta-oxo acid precursors, which are glyceride-bound in the milk fat, are synthesized in the mammary gland from acetate. The absence of heptadecan-2-one in steam-distillates and the extremely low specific radioactivity of stearic acid are further evidence for this biosynthetic pathway. 3. The specific radioactivities of the C(5)-C(15) methyl ketones were higher (with the exception of C(9) methyl ketone in the second milking) than the specific activities of the corresponding fatty acids with one more carbon atom. This is consistent with the methyl ketone precursors' being formed during the biosynthesis of fatty acids rather than being products of beta-oxidation of fatty acids.

Acetates↗

PubMed1995

Virucidal effects of the steam distillate from Houttuynia cordata and its components on HSV-1, influenza virus, and HIV.

The steam distillate prepared from fresh plants of Houttuynia cordata Thunb. (Saururaceae) was found to have direct inhibitory activity against herpes simplex virus type 1 (HSV-1), influenza virus, and human immunodeficiency virus type 1 (HIV-1) without showing cytotoxicity, but not against poliovirus and coxsackie-virus. The loss of viral infectivity was related to the duration of drug treatment. Three major components of the distillate, methyl n-nonyl ketone, lauryl aldehyde, and capryl aldehyde, also inactivated HSV-1, influenza virus, and HIV-1. These in vitro findings demonstrate that the essential oils provide virucidal activity against enveloped viruses by interfering with the function of virus envelope.

Animals↗

PubMed2000

Toxicity evaluation of petroleum blending streams: reproductive and developmental effects of light catalytic reformed naphtha distillate in rats.

A distillate of light catalytic reformed naphtha (CAS number 64741-63-5, LCRN-D) administered by inhalation was tested for reproductive and developmental toxicity in Sprague-Dawley rats, following a modified OECD Guideline 421, Reproductive/Developmental Toxicity Screening protocol. LCRN-D was administered as a vapor, 6 h/d, 7 d/wk at target concentrations of 0, 750, 2500 or 7500 ppm to female rats for approximately 6 wk from 2 wk prior to mating, during mating through gestational d 19, and to males beginning 2 wk prior to mating for approximately 7 consecutive weeks. Dams and litters were sacrificed on postnatal d 4 and males were sacrificed within the week after the last litter was necropsied. Parental systemic effects observed at the 7500 ppm exposure level included slightly lower body weights for males throughout the study. Increased kidney to body weight and increased liver to body weight ratio in male rats exposed to 7500 ppm LCRN-D may be related to slightly lower final mean body weights. Body and organ weight data for female rats in all exposure groups were comparable to controls. No test-material-related microscopic changes were observed in the reproductive organs or nasal turbinate tissue of either sex. Reproductive performance was unaffected by exposure to LCRN-D. The mating and fertility indices were 100% in all groups. There were no significant exposure-related differences in implantation sites or live pups per litter, and no gross abnormalities were observed in pups from treated dams. Pups born from LCRN-D-exposed dams showed comparable body weights and weight gain to control pups. The viability index on postpartum d 4 was > or =97%. Under conditions of this study, the no-observed-adverse-effect level (NOAEL) for exposure to light catalytic reformed naphtha distillate for parental effects was 2500 ppm and the NOAEL for reproductive and developmental toxicity was 7500 ppm.

Alkanes↗

PubMed2000

Toxicity evaluation of petroleum blending streams: inhalation subchronic toxicity/neurotoxicity study of a light catalytic reformed naphtha distillate in rats.

A 13-wk whole-body inhalation study was conducted with Sprague-Dawley CD rats (16/sex/group) exposed to a light catalytic reformed naphtha distillate (LCRN-D, CAS number 64741-63-5) at target concentrations of 0, 750, 2500, and 7500 ppm for 6 h/d, 5 d/wk. Sixteen rats per sex in the control and high-dose groups were maintained after final exposure for a 4-wk recovery period. The highest exposure concentration was 75% of the lower explosive limit. Standard parameters of subchronic toxicity were measured throughout the study; at necropsy, organs were weighed and tissues processed for microscopic evaluation. Neurotoxicity evaluations consisted of motor activity (MA) and a functional operational battery (FOB) measured pretest, throughout exposure and after the recovery period. Neuropathology was evaluated at termination. No test-related mortality or effects on physical signs, body weight, food consumption, or clinical chemistry were observed. In males exposed to 7500-ppm LCRN-D, a statistically significant decrease in white blood cell counts and lymphocyte counts was observed at the termination of exposure that was not present in animals after the 4-wk recovery period. However, mean corpuscular volume was slightly decreased in high-dose males after the recovery period. Statistically significant increases in kidney weights relative to body weights in 7500-ppm male rats correlated with microscopically observed hyaline droplet formation and renal tubule dilation, indicative of light hydrocarbon nephropathy, a condition in male rats that is not toxicologically significant for humans. Statistically significant decrease in absolute and relative spleen weights in 7500-ppm male rats correlated with decreases in hematologic parameters but had no microscopic correlate and was not observed in animals after 4 wk of recovery. This mild, reversible effect in white blood cell populations may relate to the presence of aromatics in the distillate. The only effect of LCRN-D on neurobehavioral parameters was significantly higher motor activity counts among high-dose (7500 ppm) males after the 4-wk recovery period, suggesting a possible delayed effect of LCRN-D. However, there was no evidence of hyperactivity or abnormal behavior from the functional observational battery evaluations, and there were no microscopic changes in neural tissue to support this observation. The no-observed-adverse-effects level (NOAEL) for LCRN-D was 2500 ppm for both subchronic toxicity and neurotoxicity. The no-observed-effects level (NOEL) was 750 ppm.

Administration, Inhalation↗

PubMed1998

Toxicity evaluation of petroleum blending streams: reproductive and developmental effects of a distillate from light alkylate naphtha.

A distillate of light alkylate naphtha (CAS number 64741-66-8; LAN distillate) was administered via inhalation, 6 h/d, 7 d/wk to 4 groups of Sprague-Dawley rats (10/sex/dose) at target concentrations of 0 (filtered air control), 5, 12.5, or 25 g/m3 with the highest dose exceeding 60% of the lower explosive limit of LAND. Exposure began 2 wk prior to mating and continued throughout gestation until postnatal d 4 for females or for 8 consecutive weeks for males. No apparent clinical signs indicative of systemic toxicity were observed in the F0 and F1 animals of either sex. Inhalation exposure to LAND up to and including the 25 g/m3 dose level had no effect on parental food consumption, body weights, absolute and relative organ weights, and reproductive indices. All groups had comparable delivery data and a fertility index > or 80%. Pups in all groups showed comparable birth weights, weight gain, a viability index (postnatal d 4) for all groups of > or = 97%, and no histopathological changes. In the dams, there were no significant differences in the mean numbers of corpora lutea, implantation sites, and resorptions recorded at necropsy. In the males, the only remarkable findings at necropsy were a small right epididymis and testis seen in one mid-dose male and an abscess on the right epididymis of a high-dose male. In both cases, the dams that had been bred to these males produced normal litters. There were no test material-related microscopic changes observed in the testes and epididymis of the F0 male rats or ovaries of the F0 female rats exposed to LAND. Under the conditions of this experiment, the no-observed-adverse-effect level (NOAEL) for LAND via inhalation in rats is established at greater than 24.7 g/m3 (analytical concentration).

Administration, Inhalation↗

PubMed1999

Toxicity evaluation of petroleum blending streams: reproductive and developmental effects of light catalytic cracked naphtha distillate in rats.

A distillate of light catalytic cracked naphtha (CAS number 64741-55-5, LCCN-D), administered by inhalation, was tested for reproductive and developmental toxicity in Sprague-Dawley rats, following a modified OECD Guideline 421, Reproductive/Developmental Toxicity Screening Protocol. LCCN-D was administered as a vapor, 6 h/d, 7 d/wk at target concentrations of 0, 750, 2500 or 7500 ppm to female rats for approximately 7 wk from 2 wk prior to mating, during mating through gestational d 19, and to males beginning 2 wk prior to mating for 8 consecutive weeks. Dams and litters were sacrificed on postnatal d 4, and males were sacrificed within the following week. Parental systemic effects observed at the 7500 ppm exposure level were increased kidney weights and relative liver weights in males and increased spleen weights in high-dose females. Livers and spleens from rats in the high-dose group were normal in appearance at necropsy. IncreaSed kidney weights in high-dose males were indicative of male-rat-specific light hydrocarbon nephropathy. No test-related microscopic changes were observed in the reproductive organs or nasal turbinate tissues of either sex. Reproductive performance was unaffected by treatment with LCCN-D. Fertility index was > or =90% in all dose groups. There were no exposure-related differences in implantation sites and live pups per litter, and no gross abnormalities were observed. Pups born from treated dams showed comparable body weights and weight gains to controls. The viability index on postpartum d 4 was > or =97%; the high-dose group had more male than female pups at birth and at d 4 postpartum. Under the conditions of this study, the no-observable-adverse-effect level (NOAEL) for exposure to light catalytic cracked naphtha distillate for parental toxicity was 2500 ppm and the NOAEL for reproductive performance and developmental toxicity was 7500 ppm.

Alkanes↗

PubMedDate not supplied

The problem of methanol concentration admissible in distilled fruit spirits.

Some distilled fruit spirits contain, normally, high quantities of methanol. After a brief summary of the process of methanol formation during fermentation and of the toxicological data, methanol concentrations of some distilled fruit spirits are indicated. Then, maximal amounts of methanol in spirits fixed by some countries are discussed as well as the problems which are generated by legislation.

Alcoholic Beverages↗

PubMed2005

Performance, feeding behaviour and microbial diversity in weaned piglets fed liquid diets based on water or wet wheat-distillers grain.

Performance, nutrient digestibility, feeding behaviour, diarrhoea frequency and faecal microbial diversity was studied in weaned piglets allotted to dry feed (diet A), liquid feed with water (diet B) or liquid feed with wet wheat-distillers grain (diet C). There were no differences in digestibility of organic matter and energy, and the performance was similar between piglets fed liquid diets. Piglets fed diet A spent more time on eating/drinking compared with piglets fed liquid diets. The frequency of diarrhoea decreased (p < 0.05) from from diet A (11 out of 16) to diet B (6 out of 16) and further to diet C (1 out 16). The type of diet did not affect the diversity of coliform bacteria or lactobacilli, but the composition of the Lactobacillus flora was changed. The lower diarrhoea frequency when feeding diet C may be due to a prophylactic effect induced by the inclusion of wet wheat-distillers grain in the diet.

Animal Feed↗

PubMed1954

Non-involvement of lysis during sporulation of Bacillus mycoides in distilled water.

Washed vegetative cells of Bacillus mycoides obtained and treated under specified conditions have been found to sporulate when shaken in distilled water under specified conditions. Within limitations of the methods, a heat-resistant cell (spore) is produced for each heat-sensitive vegetative cell present initially. Several different experiments designed to detect massive lysis and cell growth during sporulation in distilled water yielded uniformly negative results. Evidence is furnished for the conclusion that a freshly formed spore (heat-resistant cell) weighs considerably less than its progenitor vegetative cell. The observed results are most satisfactorily explained as a direct conversion of a vegetative cell to a spore.

Bacillus↗

PubMed2000

Analysis of tetrahydrofuran and methanol in distillation residue samples by automated headspace solid-phase microextraction-gas chromatography with flame ionization detection

Automated headspace solid-phase microextraction (SPME) coupled with gas chromatography and flame ionization detection is used to determine the amounts of methanol and tetrahydrofuran (THF) in distillation residue samples from a proprietary chemical reaction. A 65-micron polydimethylsiloxane/divinylbenzene SPME fiber is used to perform the extractions. Optimized extraction conditions for each analyte are determined using a parts-per-million-level methanol in water standard and a parts-per-billion-level THF in water standard. The amount of methanol and THF in distillation residue samples is quantitated by both standard addition and external standard calibration curve. The two methods of quantitation are compared.

Journal Article↗

PubMed2006

Comparison of comprehensive two-dimensional gas chromatography coupled with sulfur-chemiluminescence detector to standard methods for speciation of sulfur-containing compounds in middle distillates.

The monitoring of total sulfur content and speciation of individual sulfur-containing compounds in middle distillates is required for efficient catalyst selection and for a better understanding of the kinetics of the reactions involved in hydrotreament processes. Owing to higher resolution power and enhanced sensitivity, comprehensive two-dimensional gas chromatography (GCxGC) hyphenated to sulfur chemiluminescence detection (SCD) has recently evolved as a powerful tool for improving characterization and identification of sulfur compounds. The aim of this paper is to compare quantitatively GCxGC-SCD and various other methods commonly employed in the petroleum industry, such as X-ray fluorescence, conventional GC-SCD, and high-resolution mass spectrometry, for total sulfur content determination and speciation analysis. Different samples of middle distillates have been analyzed to demonstrate the high potential and important advantages of GCxGC-SCD for innovative and quantitative analysis of sulfur-containing compounds. More accurate and detailed results for benzothiophenes and dibenzothiophenes are presented, showing that GCxGC-SCD should become, in the future, an essential tool for sulfur speciation analysis.

Journal Article↗

PubMed2004

In vitro activity of bergamot natural essence and furocoumarin-free and distilled extracts, and their associations with boric acid, against clinical yeast isolates.

OBJECTIVES: There is very little information, to date, on the antifungal activity of bergamot oil. In this study, we investigated the in vitro activity of three bergamot oils (natural essence, furocoumarin-free extract and distilled extract) against clinically relevant Candida species. We studied the two derivatives, components of Italian pharmaceutical products, that are supposed to be less toxic than the essential oil. METHODS: In vitro susceptibility of 40 clinical isolates of Candida spp. (Candida albicans, n=20; Candida glabrata, n=13; Candida krusei, n=4; Candida tropicalis, n=2; Candida parapsilosis, n=1), associated with symptomatic and asymptomatic vulvovaginal candidiasis, was determined using a modification of the NCCLS M27-A2 broth microdilution method. MICs were evaluated for each of the oils alone and combined with sub-inhibitory concentrations of the well-known antiseptic, boric acid. To boric acid, all isolates had MIC values ranging from 0.094% to 0.187% (w/v). RESULTS: At 24 h readings, the MIC(90 )s (for all isolates) were (v/v): 5% for natural essence of bergamot, 2.5% for the furocoumarin-free extract, and 1.25% for the distilled extract. At the 48 h reading, these values increased to >10%, 5% and 2.5%, respectively. At both readings, MIC(90 )s for all oil+boric acid combinations were significantly lower than corresponding values for the oils alone (P <0.05). CONCLUSIONS: These data indicate that bergamot oils are active in vitro against Candida spp., suggesting their potential role for the topical treatment of Candida infections.

Antifungal Agents↗

PubMed1976

Toxicology of petroleum naphtha distillate vapors.

A unique opportunity was presented to observe the potentially toxic effects of an acute exposure to the vapors of petroleum naphtha distillate on a relatively large number of individuals. The immediate manifestation in all was dyspnea. The action on motor vehicle combustion suggested that some of this could have been due to oxygen deprivation; however, all individuals were dyspneic for several minutes after exposure. A few were cyanotic for several minutes after exposure. All were excited. Tremulousness and mild nausea followed the initial symptoms but were of brief duration. One individual manifested numerous premature ventricular contractions. Since his exposure was brief and since none of the others showed similar findings, it is unlikely that the exposure was causal. The central nervous system depression described in acute exposure cases of the intact (not distillate) petroleum naphtha fumes was not observed in any of this series. There were no delayed manifestations or complications.

Alkanes↗

PubMed2001

Detecting the inseparability and distillability of continuous variable states in Fock space.

The partial transposition (PT) operation is an efficient tool in detecting the inseparability of a mixed state. We give an explicit formula for the PT operation for the continuous variable states in Fock space. We then give the necessary and sufficient condition for the positivity of Gaussian operators. Based on this, a number of criteria on the inseparability and distillability for the multimode Gaussian states are naturally drawn. We finally give an explicit formula for the state in a subspace of a global Gaussian state. This formula, together with the known results for Gaussian states, gives the criteria for the inseparability and distillability in a subspace of the global Gaussian state.

Journal Article↗

PubMed2002

Activating distillation with an infinitesimal amount of bound entanglement.

We show that bipartite quantum states of any dimension, which do not have a positive partial transpose (NPPT), become 1-distillable when one adds an infinitesimal amount of bound entanglement. To this end we investigate the activation properties of a new class of symmetric bound entangled states of full rank. It is shown that in this set there exist universal activator states capable of activating the distillation of any NPPT state. The result shows that even a small amount of bound entanglement can be useful for quantum information purposes.

Journal Article↗

PubMed2002

Distilling Gaussian states with Gaussian operations is impossible.

We show that no distillation protocol for Gaussian quantum states exists that relies on (i) arbitrary local unitary operations that preserve the Gaussian character of the state and (ii) homodyne detection together with classical communication and postprocessing by means of local Gaussian unitary operations on two symmetric identically prepared copies. This is in contrast to the finite-dimensional case, where entanglement can be distilled in an iterative protocol using two copies at a time. The ramifications for the distribution of Gaussian states over large distances will be outlined. We also comment on the generality of the approach and sketch the most general form of a Gaussian local operation with classical communication in a bipartite setting.

Journal Article↗

PubMed2003

Majorization criterion for distillability of a bipartite quantum state.

Bipartite quantum states are classified into three categories: separable states, bound entangled states, and free entangled states. It is of great importance to characterize these families of states for the development of quantum information science. In this Letter, I show that the separable states and the bound entangled states have a common spectral property. More precisely, I prove that for undis-tillable-separable and bound entangled-states, the eigenvalue vector of the global system is majorized by that of the local system. This result constitutes a new sufficient condition for distillability of bipartite quantum states. This is achieved by proving that if a bipartite quantum state satisfies the reduction criterion for distillability, then it satisfies the majorization criterion for separability.

Journal Article↗