Density profiles of novel kraft pulp and TMP based foam formed thermal insulation materials observed by X-ray tomography and densitometry

Holzforschung ◽  
2018 ◽  
Vol 72 (5) ◽  
pp. 397-403 ◽  
Author(s):  
Michael Lecourt ◽  
Tiina Pöhler ◽  
Joanna Hornatowska ◽  
Lennart Salmén ◽  
Petri Jetsu

AbstractX-ray tomography and densitometry (XRT and XRD) were applied to characterise wood fibre based insulation materials, which were produced by the foam forming technology. XRT is a high resolution approach with long measurement times of around 29 h, while XRD measurement needs only a few minutes. The determination of density distribution of boards in the thickness direction was the focus of this study. Both approaches visualised well the impact of raw materials and manufacturing processes on the structure of the panels. The density profiles were dependent on the pulp applied for panel production, and the processing conditions were also influential. Air flow resistance correlated with the maximum density measured inside the board. Both XRT and XRD revealed similar trends, which are useful for the characterisation of insulation materials.

Author(s):  
Jiří Zimák ◽  
Kristýna Dalajková ◽  
Roman Donocik ◽  
Petr Krist ◽  
Daniel Reif ◽  
...  
Keyword(s):  

Minerals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 232
Author(s):  
Pedro J. Sánchez-Soto ◽  
Eduardo Garzón ◽  
Luis Pérez-Villarejo ◽  
George N. Angelopoulos ◽  
Dolores Eliche-Quesada

In this work, an examination of mining wastes of an albite deposit in south Spain was carried out using X-ray Fluorescence (XRF), X-ray diffraction (XRD), particle size analysis, thermo-dilatometry and Differential Thermal Analysis (DTA) and Thermogravimetric (TG) analysis, followed by the determination of the main ceramic properties. The albite content in two selected samples was high (65–40 wt. %), accompanied by quartz (25–40 wt. %) and other minor minerals identified by XRD, mainly kaolinite, in agreement with the high content of silica and alumina determined by XRF. The content of Na2O was in the range 5.44–3.09 wt. %, being associated with albite. The iron content was very low (<0.75 wt. %). The kaolinite content in the waste was estimated from ~8 to 32 wt. %. The particle size analysis indicated values of 11–31 wt. % of particles <63 µm. The ceramic properties of fired samples (1000–1350 °C) showed progressive shrinkage by the thermal effect, with water absorption and open porosity almost at zero at 1200–1250 °C. At 1200 °C, the bulk density reached a maximum value of 2.38 g/cm3. An abrupt change in the phase evolution by XRD was found from 1150 to 1200 °C, with the disappearance of albite by melting in accordance with the predictions of the phase diagram SiO2-Al2O3-Na2O and the system albite-quartz. These fired materials contained as main crystalline phases quartz and mullite. Quartz was present in the raw samples and mullite was formed by decomposition of kaolinite. The observation of mullite forming needle-shape crystals was revealed by Scanning Electron Microscopy (SEM). The formation of fully densified and vitrified mullite materials by firing treatments was demonstrated.


1962 ◽  
Vol 28 (2) ◽  
pp. 234-238 ◽  
Author(s):  
Edward J. Olsen

AbstractThe X-ray spectrometer method as an archaeological tool is discussed with special reference to its limitations as a chemical analytical instrument. Qualitative results are presented for six North American copper samples, one European trade brass, and nine artifacts from the Great Lakes region. From this pilot study it is concluded that the most fruitful results in the problem of the determination of provenance of copper artifacts will be obtained from semi-quantitative optical spectographic analyses of carefully collected artifacts and raw materials. The largest inherent error in this problem is that of meaningful sampling techniques. The only recourse is to treat such chemical data statistically and determine the probabilities that given specimens came from the various possible sources.


2021 ◽  
Vol 87 (8) ◽  
pp. 19-22
Author(s):  
D. G. Filatova ◽  
A. A. Arkhipenko ◽  
M. A. Statkus ◽  
I. V. Mikheev ◽  
V. B. Baranovskaya ◽  
...  

An approach to the simultaneous isolation of As (III) and Se (IV) from solutions on a new S,N-containing sorbent followed by determination of the analyte in the sorbent phase using total reflection X-ray fluorescence (TXRF) has been proposed. To match the goal, a sorbent with a branched structure was synthesized on the base of polyacrylamide modified with formaldehyde and hydrogen sulfide. This is a heteroatomic copolymer containing sulfide bridges in the chain and crosslinking by a tertiary amine. Conditions for the quantitative co-extraction of As (III) and Se (IV), i.e., sorption in solutions of 1 M HNO3 with calcium ions present, heating to 60°C and phase contact time of 1 h were determined. The mechanism of sorption interaction of the analytes under specified conditions is discussed. It is shown that a 100-fold excess of iron, zinc and copper does not interfere with the extraction of analytes, thus providing the possibility of As (III) and Se (IV) isolation from different types of raw materials and processed products using the synthesized sorbent. A method for the direct XRF quantification of arsenic and selenium with sr 0.09 and 0.08, respectively, in the sorbent phase has been developed. The correctness of the results was confirmed by the ICP-MS method in analysis of aqueous reference solution after dissolution of the sorbate in HNO3 (1:1).


1970 ◽  
Vol 19 (6) ◽  
pp. 812-818
Author(s):  
Hiroshi UCHIKAWA ◽  
Masahiro NUMATA
Keyword(s):  

Author(s):  
N. B. Kondratyev ◽  
E. V. Kazantsev ◽  
M. V. Osipov ◽  
O. S. Rudenko ◽  
E. N. Krylova

Sulfur dioxide is used to ensure the safety of fruit raw materials and semi-finished products used for the production of confectionery. This preservative has allergenic properties. In accordance with the Technical Regulations of the Customs Union TR CU 022/2011 "Food products in terms of their labeling" the content of sulfur dioxide must be specified when labeling confectionery products, if its content exceeds 10 mg per kg. The definition of this preservative in raw materials, semi-finished products and confectionery in accordance with the current GOST 26811 “Confectionery. The iodometric method for determining the mass fraction of total sulfuric acid is often difficult because of the complexity of confectionery products, the formation of intensive staining of the solutions under study and the ability of sulfur dioxide to react with other components of the objects under study. Therefore, the task of developing methods with the optimization of the sample preparation stage of the samples under study, which allow one to fully determine sulfur dioxide in confectionery products, semi-finished products and raw materials, is relevant. The purpose of this work was to develop methods for determining sulfur dioxide in raw materials, semi-finished products and various names of confectionery products, as well as assessing the impact of these types of raw materials and semi-finished products on the content of sulfur dioxide in confectionery products. The results showed that sulfur dioxide is present in many raw materials. In mg per 1 kg of sugar in white sand from 1 to 9, molasses from 25 to 52, wheat flour from 9 to 15, starch from 3 to 17. In fruit raw materials from 5 to 545 mg per kg. In confectionery: marshmallow and marshmallow from 8 to 29, gingerbread from 6 to 25, biscuits from 0 to 16, chocolate from 8 to 13. Based on the data obtained, it can be concluded that the content of sulfur dioxide in raw materials and semi-finished confectionery products is a very wide range, which makes it necessary to control the quality of all raw materials entering the production. Sulfur dioxide, used as a preservative for fruit raw materials, can significantly increase the content of this allergen in confectionery made using such raw materials. Ensuring the level of sulfur dioxide less than 10 mg / kg is achieved using raw materials with low content of sulfur dioxide and technological methods.


2018 ◽  
Vol 284 ◽  
pp. 1018-1023
Author(s):  
A.V. Khandoshka ◽  
Svetlana G. Vlasova

The composition of mineral wool was selected for the research, based on the chemical composition of the raw materials, the determination of the acidity module to obtain the thermal insulation material with the best characteristics and the lowest cost of the production of basalt mineral wool. The paper deals with compositions of raw materials and selection chemical compositions of charges for production of basalt mineral wool, and the experiments of welded samples were made and tested for viscosity, surface tension, chemical analysis and x-ray analysis.


Author(s):  
Jiří Zimák ◽  
Kristýna Dalajková ◽  
Roman Donocik ◽  
Petr Krist ◽  
Daniel Reif ◽  
...  
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document