Hygrothermal performance of various Typha–clay composite

2018 ◽  
Vol 42 (3) ◽  
pp. 316-335 ◽  
Author(s):  
Ibrahim Niang ◽  
Chadi Maalouf ◽  
Tala Moussa ◽  
Christophe Bliard ◽  
Etienne Samin ◽  
...  

This article deals with the influence of both morphology and amount of Typha on hygrothermal behavior of a Typha–clay composite for building application. An agromaterial containing the fiber mix of Typha Australis and clay was made in three samples: three fiber mixtures were prepared with different amounts Typha and cut type (transversal or longitudinal). The physical properties of these materials were studied in terms of porosity, apparent and absolute density, thermal conductivity, and hygric properties. Results show a real impact of the Typha fraction type and its volume content on hygrothermal properties of the studied material due to the porosity. The transversal fraction of Typha (80% in volume weight) seems to be the optimal composition for a better hygrothermal behavior.

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1622 ◽  
Author(s):  
Hamzé Karaky ◽  
Chadi Maalouf ◽  
Christophe Bliard ◽  
Tala Moussa ◽  
Nadim El Wakil ◽  
...  

This article deals with the elaboration and the characterization of an innovative 100% plant-based green composite made solely of beet pulp (BP) and potato starch (S). Using this type of material in insulation applications seems a good solution to reduce the CO2 gas emissions in building. The influence of the starch amount on composite characteristics was studied. Four mixtures were considered with different S/BP mass ratios (0.1, 0.2, 0.3 and 0.4). The physical properties of these materials were studied in terms of porosity, apparent and absolute densities, thermal conductivity, and hygric properties. The influence of humidity content on acoustical properties was studied as a function of frequency. Test results show a real impact of both starch and humidity contents on the hygrothermal and acoustical properties of the studied material due to the porosity. The composite with the lowest amount of starch (S/BP = 0.1) seems to be the optimal composition in terms of the hygrothermal and acoustical behaviors.


Alloy Digest ◽  
2020 ◽  
Vol 69 (9) ◽  

Abstract Schmelzmetall Hovadur CCZ is a heat-treatable, copper-chromium-zirconium alloy. In the solution heat-treated and artificially aged condition, this alloy exhibits high thermal and electrical conductivity along with high strength and a high softening temperature. Hovadur CCZ evolved from CuCr1 (CW105C), a precipitation-hardenable alloy first made in the 1930s for spot welding electrodes, for which strength and hardness at temperatures up to 500 °C (930 °F), as well as good electrical and thermal conductivity, are essential. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on forming, heat treating, machining, and joining. Filing Code: Cu-912. Producer or source: Schmelzmetall AG.


Author(s):  
Abhishek Chatterjee ◽  
Dileep Singh Baghel ◽  
Bimlesh Kumar ◽  
Saurabh Singh ◽  
Narendra Kumar Pandey ◽  
...  

Objective: The aims of the present investigation were to develop the herbal and/or herbomineral formulations of Hinguleswara rasa and to compare their anti-inflammatory and antioxidant activities, in vitro, with that of standard drug samples.Methods: This study was an interventional investigation in three samples: In the first sample, Hinguleswara rasa (HR1) was prepared as per methodology described in Rasatarangini using Shuddha Hingula (10 g), Shuddha Vatsanabha (10 g), and Pippali (10 g). In the second and third sample, respectively, Hinguleswara rasa was prepared by replacing Shuddha Hingula with Kajjali where Kajjali made from Hingulotha parada and Sodhita parada constitutes two varieties of Hinguleswara rasa, i.e. HR2 and HR3. In vitro antioxidant activity was studied using 2,2-diphenyl-1-picrylhydrazyl, and the absorbance was recorded at 517 nm. For evaluating the in vitro anti-inflammatory studies, the inhibition of albumin denaturation technique was performed.Results: The results showed that the formulation of Hinguleswara rasa has shown dose-dependent activity which was observed in 100 μg concentration. HR1, HR2, and HR3 showed 36.11, 17.22, and 16.11% radical scavenging activity.Conclusion: It could be concluded that the changes made in the formulations did not affect the in vitro anti-inflammatory and antioxidant effects of the herbomineral formulations.


2019 ◽  
Vol 808 ◽  
pp. 103-108
Author(s):  
Lenka Mészárosová ◽  
Vít Černý ◽  
Rostislav Drochytka ◽  
Winfried Malorny

Development of new material is focused on modification of properties of materials with silicate binder so that these could be used for renovation of horizontal structures of high-temperature devices and at the same time contribute to reduction of heat transportation of constructions with higher surface temperature (in this case 200 and 500 °C). Main requirements for this material is low volume weight and low coefficient of thermal conductivity. This paper assesses influence of exposition to higher temperatures on microstructure.


1970 ◽  
Vol 21 (2) ◽  
pp. 195 ◽  
Author(s):  
PC Whiteman ◽  
A Lulhan

Plantings of D. uncinatum and P. atropuvpureus were made in October and December 1965 and February and April 1966, and subsequently the plots were either rotationally grazed by sheep, cut with a mower at 3 inches, or left undefoliated. Monthly samples were taken to determine individual plant dry weight, nodule weight per plant, nodule number, and mean weight per nodule. Three samples for plot dry matter yield were also taken. Individual plant dry weight was higher in the October and December sowings, although by the end of the second growing season dry matter yield per plot was higher in the December and February sowings. Dry matter yield of legume was depressed by April planting. D. uncinatum began regrowth in spring 2 months earlier than P, atropurpureus, when minimum temperatures exceeded 48-50�F compared with 57' for P. atropurpureus. Both species had marked seasonal peaks in nodule and plant dry weight. The rapid decline in nodule weight could not be directly related to the onset of flowering or frosts. Grazing caused a greater reduction than cutting in terms of plant and nodule weight and legume yield. In P. atropurpureus nodule weight per plant was reduced through a decline in mean weight per nodule, while in D. uncinatum grazing and cutting reduced nodule number per plant.


1969 ◽  
Vol 42 (5) ◽  
pp. 1314-1320 ◽  
Author(s):  
J. H. Atkins ◽  
J. E. Sullivan

Abstract An instrument to measure thermal conductivity of cured rubber stocks is described. The apparatus can be used with readily available equipment or additional equipment may be purchased. The results obtained are as accurate and precise as those obtained using other instruments and can be done at a rate of three samples per hour. The apparatus is designed around a calibrated heat flux probe which measures the sample's heat flux. The heat flux, the temperature drop across the sample, and the sample thickness values permit conversion of the above data into a thermal conductivity value. Thirteen samples of Butyl rubber in a curing bladder formulation with 40-part loadings of various carbon blacks were prepared and tested. The thermal conductivity values obtained varied from 0.096 to 0.117 (Btu)/(ft2) (hr)(°F/ft) over a range of 95° F to 212° F with an overall relative standard deviation of 1.2%. The thermal conductivity of the above samples were also measured on a modified apparatus over a temperature range of 95° F to 350° F and there was no change in the thermal conductivity values. To check the above measurements, five of the samples were tested on two commercial instruments. The results agreed within 4 per cent. For reasons explained in the paper, we believe our results to be the most accurate.


1994 ◽  
Vol 123 (3) ◽  
pp. 313-317 ◽  
Author(s):  
A. Hadjichristodoulou

SUMMARYThe progenies of six crosses, made in 1987, between the best available hooded barley line and six selected awned barley lines were used to study the effect of the hooded gene on the performance of barley under rainfed conditions in Cyprus. A single dominant gene was found to control the hooded character. Awned genotypes on average outyielded hooded genotypes by 17%, but the difference between the two genotypes was smaller in the central plain than in the coastal area. The effect of the hooded gene on yield varied also with the combination of parents, as the superiority of the awned genotypes varied with cross from 13 to 30%. Hooded lines giving a higher grain yield than their hooded parent were identified. On average the awned genotypes had higher 1000-grain weight (5·0 g), were slightly later in heading date (1·1 days), had slightly higher volume weight (1·3 kg/hl) than hooded genotypes, but had similar plant height. The 1000-grain weight of most hooded lines was significantly higher than that of their hooded parent.In spite of the negative effects of the hooded gene on grain yield, it was concluded that it is possible to increase the yield of hooded barley for hay production by continued crossing and selection (with special emphasis on 1000-grain weight), by selecting special combinations of parents through the Bulk-Pedigree method and by growing hooded barley in suitable areas, making use of the locationdependent performance of the hooded gene.


1890 ◽  
Vol 35 (4) ◽  
pp. 947-954 ◽  
Author(s):  
A. Crichton Mitchell

Until a few years ago it was the general opinion among metallurgists that the presence of manganese in steel exceeding the proportion of 1 per cent, is prejudicial to the value of the steel, inasmuch as a higher percentage of manganese has the effect of lowering markedly its tensile strength and toughness. But in 1884, Messrs Hadfield & Company, of the Hecla Steel Works, Sheffield, exhibited, at a meeting of the Institute of Mechanical Engineers, a number of samples of steel containing upwards of 10 to 15 per cent, of manganese, and submitted the results of experiments, which showed that the samples were, in point of tensile strength and hardness, in no way inferior to steel. Again, in 1888, Mr R. A. Hadfield read to the Institute a paper on the subject, giving the details of a large number of tests, which brought to light some interesting mechanical properties of alloys of manganese and iron. Since its introduction, these alloys (and particularly that containing 10 to 15 per cent, of manganese, known as “manganese-steel”) have been studied by several physicists, and further peculiarities have been found. It appeared desirable that the thermal conductivity of so peculiar a substance should be investigated. The present paper is an account of experiments made in the Physical Laboratory, Edinburgh University, with a view to the determination of its thermal conductivity. In the reduction of such experiments a knowledge of the specific heat is necessary, hence there is also given an account of experiments whereby the specific heat was determined.


2011 ◽  
Vol 117-119 ◽  
pp. 1067-1070
Author(s):  
Jun Ji ◽  
Hou De Han ◽  
An Kang Kan

Vacuum insulation panels are distinguished by their outstandingly low thermal conductivity, which is approximately 0.004 W/ (m • K) to 0.01 W/ (m • K), only 33% to 10% of that of the traditional heat preservation materials. The heat preservation mechanism of vacuum insulation panels is elaborated in the study. The thermal conductivity of the vacuum insulation panel made in our lab were below 0.01 W/ (m • K). By analysis and calculation, with this kind of VIPs applied to refrigerated containers, its exciting properties can save energy consumption by more than 20% compared with traditional heat preservation materials.


2014 ◽  
Vol 982 ◽  
pp. 27-31 ◽  
Author(s):  
Václav Kočí ◽  
Miloš Jerman ◽  
Jiří Maděra ◽  
Robert Černý

This paper aims at computational simulation of effect of zeolite admixture on service life of concrete building envelope from point of view of freeze/thaw resistance. Hygrothermal behavior of two types of concrete is studied in this paper: reference concrete without any admixtures and zeolite concrete with 40 % zeolite as cement replacement. The computations are performed using computer simulation tool HEMOT, which processes the input parameters using finite element method. The simulation is assumed under dynamic climatic conditions of Prague. As the results of the computational simulations showed, assuming analyzed amount of zeolite, any positive effect of on freeze/thaw resistance was not found related to unprotected building envelope. However, the results indicated, hygrothermal performance of zeolite concrete can be very considerate to applied external layers and thus extend their service life.


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