scholarly journals Notes About the Specific Chemical Composition of "Black Shales" from Site 367 (Leg 41)

1978 ◽  
Author(s):  
J. Lang ◽  
K.H. Wedepohl ◽  
H. Heinrichs ◽  
E. Gohn
Keyword(s):  
Chemical Composition ◽  
Black Shales ◽  
Specific Chemical

scholarly journals Variation of the Chemical Composition of Waste Cooking Oils upon Bentonite Filtration

Resources ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 108 ◽  
Author(s):  
Alberto Mannu ◽  
Gina Vlahopoulou ◽  
Paolo Urgeghe ◽  
Monica Ferro ◽  
Alessandra Del Caro ◽  
...  
Keyword(s):  
Particle Size ◽  
Chemical Composition ◽  
Solid Phase ◽  
Volatile Fraction ◽  
X Ray Diffraction ◽  
Specific Chemical ◽  
Waste Cooking Oils ◽  
Main Components ◽  
Cooking Oils ◽  
Chemical Groups

The chemical composition and the color of samples of waste cooking oils (WCOs) were determined prior to and after filtration on two different pads of bentonite differing in particle size. The volatile fraction was monitored by headspace solid-phase microextraction (HS-SPME) coupled with gas-chromatography, while the variation of the composition of the main components was analyzed by 1H NMR. Both techniques allowed the detection of some decomposition products, such as polymers, terpenes, and derivatives of the Maillard process. The analysis of the chemical composition prior to and after bentonite treatment revealed a tendency for the clays to retain specific chemical groups (such as carboxylic acids or double bonds), independent of their particle size. A pair comparison test was conducted in order to detect the sensory differences of the intensity of aroma between the WCO treated with the two different bentonites. In addition, characterization of the bentonite by means of powder X-ray diffraction (XRD) and thermogravimetric measurements (TG) was performed.

The influence of fixation on the morphology of mitotic chromosomes

1986 ◽  
Vol 28 (4) ◽  
pp. 536-539 ◽  
Author(s):  
Axel J. J. Dietrich
Keyword(s):  
Acetic Acid ◽  
Chemical Composition ◽  
Strong Influence ◽  
Chromosome Structure ◽  
Human Lymphocytes ◽  
Chromosome Morphology ◽  
Mitotic Chromosomes ◽  
Specific Chemical ◽  
C Banding ◽  
Sister Chromatids

It is well known that there is a strong influence of fixation, i.e., acetic methanol versus formaldehyde, on the chromosome morphology at stages of the first meiotic division. In this study the influence of both these types of fixation on the morphology of mitotic chromosomes was examined in human lymphocytes. After methanol – acetic acid (3:1) fixation, the chromosomes show the "classical" condensed shape in which it is not always possible to recognize the two sister chromatids. These chromosomes are accessible to the conventional G-, R-, and C-banding techniques. After formaldehyde fixation at a relatively high pH, the chromosomes are thinner and longer (two to six times) when compared with chromosomes following methanol – acetic acid fixation. They show a scaffold-like morphology, sometimes with a halo of thin material around it. In all cases the two sister chromatids could be recognized. This chromosome structure could be easily stained with silver, Giemsa, 4,6-diamino-2-phenyl-indole (DAPI), and fluorescein isocyanate isomere 1 (FITC). The results obtained following these stainings gave no indication to any specific chemical composition of a probable central scaffold. The scaffold-like structures were not accessible to G-, R-, or C-banding techniques. The only effect observed following these banding techniques was the disappearance of the halo of thin material around the central scaffold-like structure.Key words: chromosome structure, fixation influence, human lymphocytes.

Elaboration of weatherproof steel 06гн3мд for structures of bridges exploited in coastal zone

2021 ◽  
Vol 77 (7) ◽  
pp. 811-819
Author(s):  
G. A. Kunitsin ◽  
А. А. Pridein ◽  
O. V. Samokhina ◽  
D. V. Nizhel’skii ◽  
E. M. Gitman
Keyword(s):  
Corrosion Resistance ◽  
Chemical Composition ◽  
Nickel Content ◽  
Research Work ◽  
Steel Structures ◽  
Surface Cleaning ◽  
Protective Film ◽  
Laboratory Studies ◽  
Specific Chemical ◽  
Climate Conditions

At present decreasing of costs and increasing of efficiency are the most priority directions in any industry. Developing in this way, JSC “Ural steel” together with FGUP “CNIIchermet after I.P. Barding” had mastered production of sheet metal product with increased resistivity against atmosphere corrosion made of steel 14ХГНДЦ for construction of bridges. Because of specific chemical composition of the steel, in the process of metal structures running in the open air, a solid strong oxide film is formed on the metal of the structures which prevents further corrosion without painting. For bridge builders elimination of costly operation of painting of span structures will enable to decrease considerably the costs of bridges construction and running. Having many advantages, steel 14ХГНДЦ has some restrictions in applications for steel structures without painting, as follows: - in sea zone according to domestic norms no close than 500 m from coastline; - in case of disorderly conditions of protective film formation and/or application of salt solutions for surface cleaning (as a rule the restrictions refer to traffic area of bridge span). In view of that for JSC “Ural Steel”, as the leading producer of bridge steel in Russia, an actual task erose: to elaborate and create a weatherproof steel, which could not only operate the whole period of a bridge running without additional protection at bridges con­struction through sea areas or close to coastline, but also withstand severe climate conditions of our country, including areas of High North with temperature lower -50°С. To solve the task together with OJSC “Institute Giprostroymost” and JSC BNIIZhT, a research work was accomplished to elaborate a system of alloying new steel 06ГН3МД with nickel content ~3.0 %, as well as production modes ensuring required corrosion resistance for operation in sea zone. Results of laboratory studies of the new weatherproof steel 06ГН3МД for application in bridge  structures for coastal conditions and sea areas presented. Results of mechanical, technological, corrosion as well as fatigue tests of rolling products of the elaborated steel presented. It was established by laboratory studies that the new steel is weatherproofed and ensures lower corrosion losses, higher impact toughness at negative temperatures and plasticity comparing with steels used at present. It was shown that the strength class, technology and modes of factory welding of steel 06ГН3МД meet the  requirements to steel span structures of bridges. Base on the results of the studies, the chemical composition of the steel 06ГН3МД was specified, as well as modes of heat treatment, ensuring the required characteristics with significant acceding. It was established that samples of the new steel 06ГН3МД showed considerably higher corrosion resistance - in average by 20% comparing with steel 14ХГНДЦ. At that corrosion resistance tests of welded joints of the new steel showed even higher resistance of the seam comparing with the basic metal, which speaks about quality selection of welding modes and welding materials.

scholarly journals Atmospheric chemistry and physics in the atmosphere of a developed megacity (London): an overview of the REPARTEE experiment and its conclusions

2012 ◽  
Vol 12 (6) ◽  
pp. 3065-3114 ◽  
Author(s):  
R. M. Harrison ◽  
M. Dall'Osto ◽  
D. C. S. Beddows ◽  
A. J. Thorpe ◽  
W. J. Bloss ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Gas Phase ◽  
Atmospheric Chemistry ◽  
Urban Atmosphere ◽  
Trace Gas ◽  
Chemical Components ◽  
Chemical Transformations ◽  
Specific Chemical ◽  
Gas Dispersion ◽  
Wide Range

Abstract. The REgents PARk and Tower Environmental Experiment (REPARTEE) comprised two campaigns in London in October 2006 and October/November 2007. The experiment design involved measurements at a heavily trafficked roadside site, two urban background sites and an elevated site at 160–190 m above ground on the BT Tower, supplemented in the second campaign by Doppler lidar measurements of atmospheric vertical structure. A wide range of measurements of airborne particle physical metrics and chemical composition were made as well as measurements of a considerable range of gas phase species and the fluxes of both particulate and gas phase substances. Significant findings include (a) demonstration of the evaporation of traffic-generated nanoparticles during both horizontal and vertical atmospheric transport; (b) generation of a large base of information on the fluxes of nanoparticles, accumulation mode particles and specific chemical components of the aerosol and a range of gas phase species, as well as the elucidation of key processes and comparison with emissions inventories; (c) quantification of vertical gradients in selected aerosol and trace gas species which has demonstrated the important role of regional transport in influencing concentrations of sulphate, nitrate and secondary organic compounds within the atmosphere of London; (d) generation of new data on the atmospheric structure and turbulence above London, including the estimation of mixed layer depths; (e) provision of new data on trace gas dispersion in the urban atmosphere through the release of purposeful tracers; (f) the determination of spatial differences in aerosol particle size distributions and their interpretation in terms of sources and physico-chemical transformations; (g) studies of the nocturnal oxidation of nitrogen oxides and of the diurnal behaviour of nitrate aerosol in the urban atmosphere, and (h) new information on the chemical composition and source apportionment of particulate matter size fractions in the atmosphere of London derived both from bulk chemical analysis and aerosol mass spectrometry with two instrument types.

scholarly journals Subglacial Cavitation Phenomena Under the Glacier D’Argentière, Mont Blanc, France

1973 ◽  
Vol 12 (66) ◽  
pp. 439-451 ◽  
Author(s):  
Robert Vivian ◽  
Gerard Bocquet
Keyword(s):  
Chemical Composition ◽  
Specific Chemical ◽  
Basal Ice ◽  
Rock Bed ◽  
Glacier Flow

The works undertaken on the Glacier d’Argentière in order to divert the subglacial stream, have allowed access to several natural cavities which correspond to places where the glacier loses contact with its rock bed. These cavities show a certain number of original phenomena both on the rock bed and also on the ice arch. Studies of the basal ice layer reveal peculiar characteristics which distinguish it from the rest of the ice mass: lamination, interstratification of ice containing sand with pure ice, crystallographic composition, and specific chemical composition. The sliding speeds of the glacier are variable, and an increase in the friction below these cavitations is at the origin of a form of regressive glacial cavitation. The subglacial cavities are grouped together in a network transverse to the direction of glacier flow; they are interconnected by channels which are more or less open which allow proper thermal exchanges to be established and favour sliding.

Orthonormal Processing of Metals. Part 1: Concept and Theory

1982 ◽  
Vol 104 (4) ◽  
pp. 327-331 ◽  
Author(s):  
N. P. Suh
Keyword(s):  
Chemical Composition ◽  
Liquid Mixture ◽  
Process Variable ◽  
Metal Part ◽  
Specific Chemical ◽  
Turbulent Eddies ◽  
Unique Manner ◽  
Metal Processing ◽  
Processing Techniques ◽  
Kinetics Of

Many metal processing techniques are dictated by equilibrium thermodynamics and the kinetics of phase transformation. Consequently, an alloy of a specific chemical composition must be processed in a unique manner to obtain the desired postprocessing microstructure and, therefore, the properties. In this respect conventional processes are coupled; any change in any one process variable and/or the chemical composition affects all the properties of the metal part. This limitation can be eliminated by using orthonormal processing techniques which allow the uncoupling of processing and properties. Examples of Orthonormal Metal Processing (OMP) techniques are given in this paper. A newly developed process comprises the impingement of two or more streams of liquid metal components (which mix due to turbulent eddies) and freezing the liquid mixture rapidly. This process can create a variety of microstructures of various metal compositions. Part 1 of this paper describes the concept and theory. Part 2 presents the experimental results.

scholarly journals Small-dispersed dust chemical composition on the leaves of apricot trees (Prunus armeniaca) in residential area

2019 ◽  
Vol 138 ◽  
pp. 01021
Author(s):  
Irina Glinyanova
Keyword(s):  
Chemical Composition ◽  
Chemical Elements ◽  
Environmental Pollutants ◽  
Residential Area ◽  
Prunus Armeniaca ◽  
Dust Particles ◽  
Specific Chemical ◽  
Atmospheric Air ◽  
Volgograd Region ◽  
Environmental Measures

A study of the small-dispersed dust chemical composition on the leaves of apricot trees (Prunus armeniaca) in the residential area of the Sredneakhtubinsky district of the Volgograd region was coducted. The aim of the study was to assess the environmental situation in low-rise buildings near functioning constructional and machinery enterprises. The leaves of apricot trees (Prunus armeniaca), growing in the residential area, were used as passive biomonitors. Chemical analysis of dust particles was carried out with the usage of a scanning electron microscope Versa 3D Dual Beam. As a result of the studies, the chemical composition of small-dispersed dust (PM1, PM2,5, PM10) on the leaves of apricot trees (Prunus armeniaca), which consisted of C,O, Mg, Al, Si, Cl, K, Ca, F, P, S, Fe, Mo. Chemical elements such as: F, P, S, Fe, Mo are not specific for leaf blades of apricot trees (Prunus armeniaca) and are environmental pollutants that have fallen on the leaves of apricot trees (Prunus armeniaca) from atmospheric air. In the future, it is necessary to find out the sources of atmospheric air pollution in the residential area by non-specific chemical elements and their compounds for this type of plant in the Sredneahtubinsky district of the Volgograd region, and to develop a set of environmental measures aimed to reduce pollutants emissions into the environment, and improving the quality of life of the population.

Photoacoustic Analysis of Natural Indigo, Palygorskite and Synthetic Maya Blue

2012 ◽  
Vol 1374 ◽  
pp. 275-281
Author(s):  
Carlos Aldebarán Rosales Córdova ◽  
Antonio de Ita de la Torre ◽  
Rosalba Castañeda Guzman
Keyword(s):  
Chemical Composition ◽  
High Temperatures ◽  
Structural Changes ◽  
Climatic Conditions ◽  
Blue Dye ◽  
Inorganic Pigment ◽  
Specific Chemical ◽  
Maya Blue ◽  
White Clay ◽  
Implementation Technique

ABSTRACTMaya blue is an organic / inorganic pigment which is composed principally by two elements: a white clay known as palygorskite (in the Mayan dialect Sakalum), and a blue dye called indigo, this dye is extracted from the plant Indigofera suffruticosa. The mixture and the warming of these two elements produce the Maya blue, which exhibits unusual features such as: resistance to the assault of the acids in warm or high temperatures, his persistent color in spite of having been exposed to different climatic conditions as a result of the passage of time and the specific chemical composition that this pigment presents.In the present investigation natural indigo, palygorskite and synthetic maya blue were analyzed with a new implementation technique called photoacoustic analysis, which detects the structural changes that happen in the material under a controlled increase of temperature. Due to the fact that this technology detects with clarity where the structural changes happen but not that type of changes happen, it used as base termogravimetric analysis. One of the important findings, it was that in the spectrum of the synthetic maya blue were detected the structural changes of the clay and the dye, something that with other used technologies had not been achieved to observe.

scholarly journals Submicroscopic Organization of Retinal Cones of the Rabbit

1958 ◽  
Vol 4 (6) ◽  
pp. 743-746 ◽  
Author(s):  
Eduardo De Robertis ◽  
Arnaldo Lasansky
Keyword(s):  
Endoplasmic Reticulum ◽  
Fine Structure ◽  
Chemical Composition ◽  
Outer Segment ◽  
Distal Portion ◽  
Cone Cell ◽  
Specific Chemical ◽  
General Plan ◽  
Clear Space ◽  
And Function

The fine structure of the cone cell of the rabbit is described and compared wtih that of the rod. The cone outer segment consists of a pile of flattened sacs with two membranes 30 A thick and a regular clear space in between of about 30 A. The membrane of the rod sacs is slightly thicker (∼40 A) and the clear space is less regular and frequently absent in the deeper regions. The distance between sacs is from 85 to 95 A in the cone and from 110 to 120 A in the rod, and the total repeating period is about 190 A and 210 A, respectively. These results are discussed in relation to the concentration of solids in both photoreceptors. A connecting cilium was observed in the cone cell and compared with that previously described in rods (4). This finding suggests that morphogenetically the cone may also result of the differentiation of a primitive cilium (5). The inner segment of the cone shows a distal portion with large concentration of elongated mitochondria and a proximal one with a large Golgi complex in the axis surrounded by components of the endoplasmic reticulum. It is concluded that both photoreceptors have a similar general plan of submicroscopic organization, with some minor difference in fine structure probably related to their specific chemical composition and function.

scholarly journals Determining Chemical Composition of Cattle Urine and Indigenous Plant Extracts

2017 ◽  
Vol 3 (1) ◽  
pp. 23-26
Author(s):  
Md. Nur Alam Miah ◽  
M. R. U. Miah ◽  
M. Z. Alam
Keyword(s):  
Chemical Composition ◽  
Plant Extracts ◽  
Chemical Constituents ◽  
Insect Pest ◽  
Chemical Compositions ◽  
Seed Kernel ◽  
Neem Seed ◽  
Specific Chemical ◽  
Indigenous Plant ◽  
Neem Seed Kernel Extracts

 The study was conducted to determine the specific chemical constituents of cattle urine and indigenous plant extracts. Chemical analysis revealed that the specific chemical composition i.e., chloride, sulphate, nitrite and phosphorus pentaoxide contents of fresh and fermented cattle urine were 1556, 364, 2.0, 26.8 and 4514, 252, 22.4, 7.49 mg l-1, respectively. The proximate chemical compositions of neem seed kernel extracts, mahagoni seed extracts and allamanda leaves extracts were analyzed and it was found to contain chloride (144, 55.4, 141 mg l-1), sulphate (51.1, 5.03, ˂4.0 mg l-1), nitrite (˂1.0, ˂1.0, ˂1.0 mg l-1) and phosphorus pentaoxide (413, 410, 49.5 mg l-1), respectively. Chloride and nitrite in fermented cattle urine (4514 and 22.4 mg l-1) was found extremely higher than in fresh cattle urine (1556 and 2.0 mg l-1). There was numerically higher difference in sulphate and phosphorus pentaoxide concentrations in fresh cattle urine (364, 26.8 mg l-1) compared to fermented cattle urine (252, 7.49 mg l-1).These results revealed that indigenous plant extracts of neem seed kernel, mahagoni seed and allamanda leaves contents chloride, sulphate and nitrite were extremely lower than in both fresh and fermented cattle urine but there were great difference in phosphorus pentaoxide concentration (413, 410, 49.5 mg l-1) in both fresh and fermented cattle urine (26.8, 7.49 mg l-1) composition. It was evident from this study that as the fermented cattle urine contained higher concentration of chloride and nitrite can be considered as a good means of insect pest management.

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