Insoluble portion of dust fallout on snow and its composition in prague

1974 ◽  
Vol 18 (2) ◽  
pp. 191-198
Author(s):  
František Anýz ◽  
Rudolf Přibil ◽  
S. Brandejs
Keyword(s):  
Insoluble Portion

Studies of Mechanical Properties and Melting Behaviour of Foamed and Crosslinked LDPE/PP Blends

2002 ◽  
Vol 21 (6) ◽  
pp. 431-443 ◽  
Author(s):  
George Kotzev
Keyword(s):  
Mechanical Properties ◽  
Melting Behaviour ◽  
Crosslinking Degree ◽  
Foaming Agent ◽  
Pp Blends ◽  
Insoluble Portion

Foamed crosslinked specimens of LDPE/PP blends produced by RIM process were examined. A crosslinking system containing 2,5-dimethyl-2,5-di(tert.-butylperoxy)hexane as an initiator and hydroquinone as a coagent was used. Azodicarbonamide was applied as a foaming agent. The crosslinking degree was evaluated by insoluble portion of the blends. An improvement of the mechanical properties due to crosslinking mainly in the LDPE phase as well as crosslinking between polyethylene and polypropylene on their interface was observed. Melting behaviour of the blends studied by DSC shows that both the initiator and the coagent cause opposite effects on temperatures and enthalpies of melting.

scholarly journals Linear Viscoelasticity and Flow of Self-Assembled Vitrimers: The Case of a Polyethylene/dioxaborolane System

2020 ◽  
Author(s):  
RALM RICARTE ◽  
François Tournilhac ◽  
Michel Cloître ◽  
Ludwik Leibler
Keyword(s):  
Self Assembly ◽  
Linear Viscoelasticity ◽  
Microphase Separation ◽  
Flow Behavior ◽  
Wide Distribution ◽  
Polymer Chains ◽  
Melt Fracture ◽  
Polymer Backbone ◽  
Cross Links ◽  
Insoluble Portion

For vitrimer systems obtained by dynamic cross-linking of polymer chains, incompatibility effects between the cross-links and polymer backbone can lead to microphase separation, resulting in a network made of cross-linked aggregates. Additionally, when there is a wide distribution of the number of cross-links per chain, macrophase separation can occur. Here, we investigate the linear viscoelasticity and flow of a polyethylene (PE) vitrimer that has cross-linkable dioxaborolane maleimide grafts, which aggregate into a hierarchical nanostructure. To elucidate the role of self-assembly, noncross-linked graft functionalized PE was first studied. It had a terminal relaxation time that was orders of magnitude larger than both neat PE and partially peroxide cross-linked PE. When dioxaborolane cross-linker was added to form the vitrimer, the resulting material could not achieve terminal relaxation within 8 hr. The graft-poor soluble and graft-rich insoluble portions of the PE vitrimer were then isolated and characterized. The soluble portion expressed similar flow behavior as neat PE, while the insoluble portion – which is a network of cross-linked aggregates – relaxed very little over 8 hr. When the insoluble and soluble portions were blended, the rheological behavior of the original vitrimer was basically recovered, showing that the soluble portion acts as a lubricant. When the insoluble portion was blended with neat PE, the material relaxed much more stress, but still did not reach steady-state flow within 8 hr. When high stresses were applied, however, PE vitrimer flowed. Nonlinear rheology experiments revealed melt fracture at high strains and suggested that flow is enabled by rapid healing, which follows fracture events. The presence of macroscopic phase separation facilitated flow.

scholarly journals Linear Viscoelasticity and Flow of Self-Assembled Vitrimers: The Case of a Polyethylene/dioxaborolane System

2019 ◽  
Author(s):  
RALM RICARTE ◽  
François Tournilhac ◽  
Michel Cloître ◽  
Ludwik Leibler
Keyword(s):  
Self Assembly ◽  
Linear Viscoelasticity ◽  
Microphase Separation ◽  
Flow Behavior ◽  
Wide Distribution ◽  
Polymer Chains ◽  
Melt Fracture ◽  
Polymer Backbone ◽  
Cross Links ◽  
Insoluble Portion

For vitrimer systems obtained by dynamic cross-linking of polymer chains, incompatibility effects between the cross-links and polymer backbone can lead to microphase separation, resulting in a network made of cross-linked aggregates. Additionally, when there is a wide distribution of the number of cross-links per chain, macrophase separation can occur. Here, we investigate the linear viscoelasticity and flow of a polyethylene (PE) vitrimer that has cross-linkable dioxaborolane maleimide grafts, which aggregate into a hierarchical nanostructure. To elucidate the role of self-assembly, noncross-linked graft functionalized PE was first studied. It had a terminal relaxation time that was orders of magnitude larger than both neat PE and partially peroxide cross-linked PE. When dioxaborolane cross-linker was added to form the vitrimer, the resulting material could not achieve terminal relaxation within 8 hr. The graft-poor soluble and graft-rich insoluble portions of the PE vitrimer were then isolated and characterized. The soluble portion expressed similar flow behavior as neat PE, while the insoluble portion – which is a network of cross-linked aggregates – relaxed very little over 8 hr. When the insoluble and soluble portions were blended, the rheological behavior of the original vitrimer was basically recovered, showing that the soluble portion acts as a lubricant. When the insoluble portion was blended with neat PE, the material relaxed much more stress, but still did not reach steady-state flow within 8 hr. When high stresses were applied, however, PE vitrimer flowed. Nonlinear rheology experiments revealed melt fracture at high strains and suggested that flow is enabled by rapid healing, which follows fracture events. The presence of macroscopic phase separation facilitated flow.

Determination of minerals in platinum concentrates from the Transvaal by X-ray methods

1932 ◽  
Vol 23 (138) ◽  
pp. 188-206 ◽  
Author(s):  
F. A. Bannister
Keyword(s):  
Solid Solution ◽  
New Mineral ◽  
Early Analysis ◽  
Aqua Regia ◽  
X Ray ◽  
Ray Methods ◽  
Platinum Mineral ◽  
Insoluble Portion

Concentrates from the platiniferous norites of the Bushveld, Transvaal, are not completely soluble in aqua regia. The insoluble portion consists of steel-grey fragments first analysed chemically by R. A. Cooper and considered by him to be a new platinum mineral represented by the formula Pt(As,S)2. The name cooperite was proposed for the new mineral by F. Wartenweiller, and after further work Cooper decided that the arsenic found in the early analysis was due to the presence of sperrylite, and he changed the formula to PtS2. H. Schneiderhöhn observed simple twinning and, less frequently, polysynthetie lamellae on polished sections of mineral grains from the same deposits, and he suggested that cooperite is probably orthorhombic and isomorphous with marcasite. The latest account of the new mineral has been published by H. R. Adam who gave several analyses of cooperite from the Rustenburg and Potgietersrust districts and concluded that the ‘mineral is PtS2 with a small amount of excess metal (platinum, palladium, and nickel) present in solid solution’.

Exhaust Emissions Characterization of a Turbocharged 2-Stroke Tier 0+ Locomotive Engine: NOx, Particulate Matter and Soluble Organic Fraction Composition

2012 ◽  
Vol 134 (7) ◽  
Author(s):  
Stanislav V. Bohac ◽  
Eric Feiler ◽  
Ian Bradbury
Keyword(s):  
Particulate Matter ◽  
Elemental Carbon ◽  
Engine Oil ◽  
Exhaust Emission ◽  
Moderate Increase ◽  
Oil Consumption ◽  
Engine Operation ◽  
Soluble Organic Fraction ◽  
Insoluble Portion

This study presents a detailed exhaust emission characterization of a 2-Stroke turbocharged line haul locomotive diesel engine fitted with an early-development Tier 0 + emissions kit. The objective of this work is to use emissions characterization to gain insight into engine operation and mechanisms of pollutant formation for this family of engine, and identify areas of potential future engine emissions improvement. Results show that at the notches tested (notches 3–8) the largest contributor to particulate matter (PM)mass is insolubles (mostly elemental carbon), but that the soluble component of PM, comprising 14–32% of PM, is also significant. Gas chromatography (GC) analysis of the soluble portion shows that it is composed of 55–77% oil-like C22–C30+ hydrocarbons, with the remainder being fuel-like C9–C21 hydrocarbons. The emissions characterization suggests that advancing combustion timing should be effective in reducing PM mass by reducing the insoluble portion (elemental carbon) of PM at all notches. NOx will likely increase, but the current level of NOx is sufficiently below Tier 0+ limits to allow a moderate increase. Reducing engine oil consumption should also reduce PM mass at all notches, although to a smaller degree than measures that reduce the insoluble portion of PM.

An Improved Alkaline Citrate Method for Evaluation of Phosphorus in Fertilizers

1964 ◽  
Vol 47 (6) ◽  
pp. 1048-1054
Author(s):  
J A Brabson ◽  
W G Burch
Keyword(s):  
The Netherlands ◽  
Extraction Method ◽  
Phosphate Rock ◽  
Field Tests ◽  
Dicalcium Phosphate ◽  
Ammonium Citrate ◽  
Citrate Solution ◽  
Citrate Method ◽  
Insoluble Portion

Abstract The Netherlands alkaline ammonium citrate extraction method for the determination of available P2O5 was modified for routine use. The water-insoluble portion of the sample is extracted with the alkaline citrate solution for 2 hours in a shaking apparatus at 65°C. Dicalcium phosphate dissolves, but apatite, whether formed in processing (as in the ammoniation of superphosphate) or present as unreacted phosphate rock, does not dissolve. The results of the extraction method correlate well with those of field tests of the fertilizers.

INFLUENCE OF VARIOUS FACTORS ON THE CONTENT OF THE MASS FRACTION OF THE INSOLUBLE PART IN HOOKAH TOBACCO

2020 ◽  
Author(s):  
Н Н БУБНОВА (МАТЮХИНА) ◽  
А.Г. МИРГОРОДСКАЯ ◽  
О.К. БЕДРИЦКАЯ
Keyword(s):  
Chemical Composition ◽  
Mass Fraction ◽  
Raw Materials ◽  
Scientific Research Institute ◽  
Tobacco Products ◽  
Russian Scientific ◽  
Russian Scientific Research Institute ◽  
Materials Used ◽  
Insoluble Part ◽  
Insoluble Portion

Исследовано влияние влажности табачного сырья, его сортотипа, количества в рецептуре на содержание массовой доли нерастворимой части в табаке для кальяна. Объектом исследования были образцы кальянных смесей разных торговых марок, приобретенных в торговой сети Краснодара и составленных в лабораторных условиях Всероссийского научно-исследовательского института табака, махорки и табачных изделий. Образцы кальянной смеси изготавливали по единой для всех образцов рецептуре и технологической схеме: увлажнение, резка, выдерживание в соусе с нагревом, охлаждение. Влажность и количество табачного сырья в рецептуре варьировали. Методом количественного определения содержания табака в готовом продукте, основанном на способности части ингредиентов кальянных смесей растворяться в воде, определяли массовую долю нерастворимой части. Установлено, что содержание массовой доли нерастворимой части в табаке для кальяна различных торговых марок, приобретенном в торговой сети Краснодара, составляет 5,2–8,8%. Сортотип табачного сырья, его химический состав и добавленный в смесь ароматизатор не влияют на содержание массовой доли нерастворимой части в табаке для кальяна. Содержание массовой доли нерастворимой части табака для кальяна в значительной степени зависит от влажности и количества табачного сырья, используемого в рецептуре. Увеличение влажности исходного сырья приводит к уменьшению массовой доли нерастворимой части в смеси для кальяна: при влажности сырья 10% массовая доля нерастворимой части 6,8%; при влажности того же сырья 16% массовая доля нерастворимой части 5,2%. The influence of humidity of tobacco raw materials, its variety type, and the amount in the recipe on the content of the mass fraction of the insoluble part in hookah tobacco has been studied. Samples of hookah mixes of various brands purchased in the retail network of Krasnodarand compiled in the laboratory of the All-Russian Scientific Research Institute of Tobacco, shag and Tobacco Products were the object of research. Samples of hookah mix were made according to the same formulation and technological scheme for all samples: humidification, cutting, keeping in a sauce with heating, cooling. The humidity and amount of tobacco raw materials in the formulation varied. By quantifying the content of tobacco in the finished product, based on the ability of some of the ingredients of hookah mixtures to dissolve in water, the content of the mass fraction of the insoluble part was determined. It is established that the content of the mass fraction of the insoluble part in hookah tobacco of various brands purchased in the retail network of Krasnodar is 5,2–8,8%. The variety type of tobacco raw materials, its chemical composition and added flavor to the mixture do not affect the content of the mass fraction of the insoluble part in hookah tobacco. The content of the mass fraction of the insoluble part of tobacco for hookah largely depends on the humidity and the amount of tobacco raw materials used in the formulation. The increase of humidity of raw materials leads to a decrease of the mass fraction of the insoluble part of hookah tobacco: if moisture content of raw materials 10% mass fraction of the insoluble portion of 6,8%; the humidity of the same raw materials 16%, the mass fraction of the insoluble portion of 5,2%.

Analysis of Ferroalloys by Atomic Absorption Spectrometry

1970 ◽  
Vol 24 (6) ◽  
pp. 576-579 ◽  
Author(s):  
D. C. Smith ◽  
J. R. Johnson ◽  
G. C. Soth
Keyword(s):  
Atomic Absorption ◽  
Iron Concentration ◽  
Absorption Spectrometry ◽  
Sodium Peroxide ◽  
Inorganic Acids ◽  
Reduction Of Iron ◽  
Laboratory Ware ◽  
Absorption Apparatus ◽  
Insoluble Portion

Atomic absorption procedures have been developed for the determination of manganese and silicon in ferromanganese and in silicomanganese, chromium and silicon in three different grades of ferrochromium, silicon in ferrosilicon, vanadium in ferrovanadium, titanium in ferrotitanium, boron in ferroboron, and columbium in ferrocolumbium. In most cases a sample is dissolved by a combination of inorganic acids, including hydrofluoric, and using plastic laboratory ware. A sodium carbonate fusion of the acid insoluble portion of ferroboron is employed. A sodium peroxide fusion is used on the acid insoluble portion of one grade of ferrochromium. No separation of elements or reduction of iron concentration is required. All procedures use a nitrous oxide–acetylene flame and a laminar flow burner with any conventional atomic absorption apparatus. Calibration curves were prepared using either U. S. Bureau of Standards samples or analyzed samples of purchased ferroalloys.

THE CARBOHYDRATE OF HUMAN SEMEN

1966 ◽  
Vol 34 (2) ◽  
pp. 257-NP ◽  
Author(s):  
T. MANN ◽  
D. A. ROTTENBERG
Keyword(s):  
Sialic Acid ◽  
Acid Hydrolysis ◽  
Room Temperature ◽  
Amino Sugar ◽  
Soluble Form ◽  
Free Sugar ◽  
Human Semen ◽  
Insoluble Portion

SUMMARY The carbohydrates of human semen are partly dialysable and ethanol-soluble, and partly non-dialysable and ethanol-insoluble. The dialysable and ethanol-soluble portion contains fructose as the principal free sugar, and, in addition, inositol, sorbitol, glucose, ribose, fucose, small amounts of certain other sugars and a polysaccharide which, on acid hydrolysis, yields mannose, fucose and amino sugar. The non-dialysable and ethanol-insoluble portion is even richer in polysaccharide material. It contains, in a bound form (g./100 ml. semen): 0·2 amino sugar, 0·1 sialic acid, and 0·4 orcinol-reactive carbohydrate material which on acid hydrolysis yields galactose, mannose, and fucose, but only a trace of glucose. On incubation of human semen at room temperature, a proteolytic breakdown of seminal proteins sets in, accompanied by a release of carbohydrate in an ethanol-soluble form. Glycogen occurs in human semen in traces only.

NON BUTANOL EXTRACTABLE IODINE IN THE SERUM OF EUMETABOLIC ADULT GOITRE PATIENTS

1963 ◽  
Vol 44 (2) ◽  
pp. 291-312 ◽  
Author(s):  
B.-A. Lamberg ◽  
G. Hintze ◽  
R. Karlsson
Keyword(s):  
Enzymatic Hydrolysis ◽  
Thyroid Hormones ◽  
Test Dose ◽  
Subtotal Thyroidectomy ◽  
Endemic Goitre ◽  
Thyrotrophic Hormone ◽  
The Difference ◽  
Do So ◽  
Insoluble Portion

ABSTRACT In studies on endemic goitre there were 20 patients who had more than a normal proportion of butanol insoluble iodine in the serum. All these patients were eumetabolic adults with a goitre ranging in size from 50 to 300 g. The insoluble portion of the PB131I (NBE131I) varied from 25 to 80 per cent, the PB131I from 0.005 to 0.94% per litre. Radiochromatography of the extract revealed that thyroxine made up 30 to 100 per cent, the remainder being iodide. In one case instead of thyroxine, 48 per cent of triiodothyronine was found. In one case traces of diiodotyrosine were found 6 hours after the test dose. Enzymatic hydrolysis increased the extractability in two cases but failed to do so in two other cases. The responses of PBI, PB131I to stimulation with thyrotrophic hormone were studied in some instances. There was usually a good response of PBI and PB131I. The reaction of NBE131I, however, was nil, or very small. The ratio between the values obtained after and before stimulation varied from 1.0 to 1.3. In contrast there was a marked increase in the difference PB131I – NBE131I which presumably represented thyroid hormones. The ratio varied from 2.5 to 3.2. In one case restudied 5 weeks and 3 months after subtotal thyroidectomy the same situation was observed. The occurrence of NBE131I was observed in two members of a family in two instances. In some other families the pedigree was also highly suggestive of an inherited disorder, although it must be admitted that the

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