Composition of the individual hydrocarbons of the naphtha fractions of West Siberian petroleum

Polyaniline-silica (PAni-silica) composite material with 40% silica was prepared by polymerization of aniline in a medium consisting of colloidal silica, freshly prepared by hydrolysis of sodium silicate at room temperature at pH 6.5. The physico-chemical properties of both PAni and the composite material, PAni-silica were studied by FT-IR and transmission electron microscopy and measurements of Brunauer- Emmett-Teller (BET) isotherms. PAni-silica composites showed inhomogeneous pore distribution, although PAni has no significant pores. Average pore size of PAni-silica was 280 and 175 Å during adsorption and desorption of nitrogen, respectively. The interactions of PAnisilica composite and PAni with saturated hydrocarbons were investigated by inverse gas chromatography. The composite material was found to be efficient for separation of a mixture of hydrocarbons, in the range of C5-C9, owing to large BET surface area. Enthalpy of adsorption of the individual hydrocarbons was evaluated from an analysis of the retention time and the flow rate of the carrier gas. For PAni, the enthalpy of adsorption was very low; however, the value for the composite material was found to be comparable to the enthalpy of evaporation of the individual hydrocarbons. DOI: http://dx.doi.org/10.3329/bjsir.v47i3.13055 Bangladesh J. Sci. Ind. Res. 47(3), 249-256, 2012

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Percutaneous absorption and skin irritation upon low-level prolonged dermal exposure to nonane, dodecane and tetradecane in hairless rats

Toxicology and Industrial Health ◽

10.1191/0748233704th197oa ◽

2004 ◽

Vol 20 (6-10) ◽

pp. 109-118 ◽

Cited By ~ 18

Author(s):

RJ Babu ◽

A Chatterjee ◽

E Ahaghotu ◽

M Singh

Keyword(s):

Skin Irritation ◽

Transepidermal Water Loss ◽

Low Level ◽

Dermal Penetration ◽

Reality Check ◽

Gradual Accumulation ◽

The Individual ◽

Individual Hydrocarbons ◽

Skin Retention

Even though the dermal toxicity of hydrocarbon fuels has been well established in the literature, there is little information available on the dermal penetration kinetics and irritation potential of the individual hydrocarbons. The penetration and skin retention of nonane, dodecane and tetradecane was assessed in vitro using hairless rats’ skin. The effects of unocclusive dermal exposures of these chemicals (15 mL every 2 h for 8 h a day for four days) on the transepidermal water loss (TEWL) and erythema were measured in CD hairless rats. The expression of interleukin 1a (IL-1a) and TNF-a in the skin and blood were measured at the end of dermal exposures. The flux of dodecane was 3- and 77-fold higher than nonane and tetradecane. The retention of chemicals in stratum corneum (SC) was in the order of tetradecane-dodecane-nonane, and directly correlated to the log Kp (r2-0.9900) and molecular weight of the chemicals (r2-0.8782). The TEWL and erythema data indicate that irritation was in the following order: tetradecane-dodecane-nonane. Likewise, the expression of IL-1a in the blood and TNF-a in the skin after dermal exposures was higher for tetradecane followed by dodecane and nonane compared to control. In conclusion, the aliphatic hydrocarbon chemicals of the present study induced cumulative irritation upon low-level repeat exposures for a four-day period. The affinity of the chemicals to SC and their gradual accumulation in the skin in the present study is the probable cause for the differences in the skin irritation profiles of different aliphatic chemicals. The findings of the present study will be helpful in understanding the skin irritation response of the chemicals in humans; indeed the reality check arises from dermal exposures in humans and human experience in occupational handling of these chemicals.

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Paraffins of Cigar Smoke

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/48.5.1059 ◽

1965 ◽

Vol 48 (5) ◽

pp. 1059-1062

Author(s):

S Osman ◽

J Barsox ◽

C J Dooley

Keyword(s):

Liquid Chromatography ◽

Column Chromatography ◽

Infrared Spectra ◽

Homologous Series ◽

Mass Spectra ◽

Chromatographic Behavior ◽

Gas Liquid Chromatography ◽

The Individual ◽

Individual Hydrocarbons

Abstract Column chromatography was used to isolate a fraction from cigar smoke condensate containing a homologous series of normal paraffinic hydrocarbons; the individual hydrocarbons were separated by gas-liquid chromatography and characterized by their infrared spectra, mass spectra, and gas chromatographic behavior. Those compounds identified include the normal paraffins from dodecane to pentacosane. This fraction was isolated from the smoke condensates of four cigar types containing unblended filler tobacco that varied considerably in smoking characteristics. Qualitatively, the four types were identical, but quantitative differences were observed.

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Comment: predictability of survival in the individual patient with lung cancer

JAMA ◽

10.1001/jama.195.12.1036 ◽

1966 ◽

Vol 195 (12) ◽

pp. 1036-1037 ◽

Cited By ~ 1

Author(s):

P. Rubin

Keyword(s):

Lung Cancer ◽

The Individual

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The Ultrastructure of Monkey Gingival Epithelium

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010006009x ◽

1967 ◽

Vol 25 ◽

pp. 16-17

Author(s):

C.N. Sun

Keyword(s):

Epithelial Cells ◽

Macaca Nemestrina ◽

Stratum Granulosum ◽

Solution Ph ◽

Gingival Epithelial Cells ◽

Stratum Spinosum ◽

Cell Layers ◽

Gingival Epithelium ◽

The Individual ◽

Different Thickness

The present study demonstrates the ultrastructure of the gingival epithelium of the pig tail monkey (Macaca nemestrina). Specimens were taken from lingual and facial gingival surfaces and fixed in Dalton's chrome osmium solution (pH 7.6) for 1 hr, dehydrated, and then embedded in Epon 812.Tonofibrils are variable in number and structure according to the different region or location of the gingival epithelial cells, the main orientation of which is parallel to the long axis of the cells. The cytoplasm of the basal epithelial cells contains a great number of tonofilaments and numerous mitochondria. The basement membrane is 300 to 400 A thick. In the cells of stratum spinosum, the tonofibrils are densely packed and increased in number (fig. 1 and 3). They seem to take on a somewhat concentric arrangement around the nucleus. The filaments may occur scattered as thin fibrils in the cytoplasm or they may be arranged in bundles of different thickness. The filaments have a diameter about 50 A. In the stratum granulosum, the cells gradually become flatted, the tonofibrils are usually thin, and the individual tonofilaments are clearly distinguishable (fig. 2). The mitochondria and endoplasmic reticulum are seldom seen in these superficial cell layers.

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A Study of the Ultrastructure of Visual Cell Outer Segment Membranes, Using a Water-Miscible Embedding Medium and Differential Staining

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010009350x ◽

1972 ◽

Vol 30 ◽

pp. 50-51

Author(s):

Anthony J. Godfrey

Keyword(s):

Outer Segment ◽

Protein Denaturation ◽

Uranyl Acetate ◽

Differential Staining ◽

Visual Cell ◽

Lead Citrate ◽

Chick Retina ◽

Dark Staining ◽

Embedding Medium ◽

The Individual

Aldehyde-fixed chick retina was embedded in a water-containing resin of glutaraldehyde and urea, without dehydration. The loss of lipids and other soluble tissue components, which is severe in routine methods involving dehydration, was thereby minimized. Osmium tetroxide post-fixation was not used, lessening the amount of protein denaturation which occurred. Ultrathin sections were stained with 1, uranyl acetate and lead citrate, 2, silicotungstic acid, or 3, osmium vapor, prior to electron microscope examination of visual cell outer segment ultrastructure, at magnifications up to 800,000.Sections stained with uranyl acetate and lead citrate (Fig. 1) showed that the individual disc membranes consisted of a central lipid core about 78Å thick in which dark-staining 40Å masses appeared to be embedded from either side.

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The Red Neuronal Pigment in the Nervous System of the Mussel, Mytilus Edulis: Localization and Its Effect on Lateral Ciliary Activity with Spectral and Analytical Changes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100098952 ◽

1981 ◽

Vol 39 ◽

pp. 494-495

Author(s):

Anthony A. Paparo ◽

Judith A. Murphy

Keyword(s):

Nervous System ◽

Mytilus Edulis ◽

Neuronal Cell ◽

Ciliary Activity ◽

Neuronal Cell Bodies ◽

The Central Nervous System ◽

Intracellular Organelles ◽

The Common ◽

The Individual ◽

Cryostat Sections

The purpose of this study was to localize the red neuronal pigment in Mytilus edulis and examine its role in the control of lateral ciliary activity in the gill. The visceral ganglia (Vg) in the central nervous system show an over al red pigmentation. Most red pigments examined in squash preps and cryostat sec tions were localized in the neuronal cell bodies and proximal axon regions. Unstained cryostat sections showed highly localized patches of this pigment scattered throughout the cells in the form of dense granular masses about 5-7 um in diameter, with the individual granules ranging from 0.6-1.3 um in diame ter. Tissue stained with Gomori's method for Fe showed bright blue granular masses of about the same size and structure as previously seen in unstained cryostat sections.Thick section microanalysis (Fig.l) confirmed both the localization and presence of Fe in the nerve cell. These nerve cells of the Vg share with other pigmented photosensitive cells the common cytostructural feature of localization of absorbing molecules in intracellular organelles where they are tightly ordered in fine substructures.

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Some Effects of Oxidant Air Pollutants (Ozone and Peroxyacetyl Nitrate) on the Ultrastructure of Leaf Tissues

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095066 ◽

1972 ◽

Vol 30 ◽

pp. 360-361

Author(s):

William W. Thomson ◽

Elizabeth S. Swanson

Keyword(s):

Air Pollutants ◽

Electron Microscopic Examination ◽

Peroxyacetyl Nitrate ◽

Electron Microscopic ◽

Growth Physiology ◽

Physiology And Biochemistry ◽

Entire Plant ◽

Leaf Tissues ◽

Gaseous Hydrocarbons ◽

The Individual

The oxidant air pollutants, ozone and peroxyacetyl nitrate, are produced in the atmosphere through the interaction of light with nitrogen oxides and gaseous hydrocarbons. These oxidants are phytotoxicants and are known to deleteriously affect plant growth, physiology, and biochemistry. In many instances they induce changes which lead to the death of cells, tissues, organs, and frequently the entire plant. The most obvious damage and biochemical changes are generally observed with leaves.Electron microscopic examination of leaves from bean (Phaseolus vulgaris L.) tobacco (Nicotiana tabacum L.) and cotton (Gossipyum hirsutum L.) fumigated for .5 to 2 hours with 0.3 -1 ppm of the individual oxidants revealed that changes in the ultrastructure of the cells occurred in a sequential fashion with time following the fumigation period. Although occasional cells showed severe damage immediately after fumigation, the most obvious change was an enhanced clarity of the cell membranes.

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