scholarly journals The study of the physical properties and composition of nutrients microalgae Spirulina platensis grown in laboratory conditions

2015 ◽  
pp. 149-152
Author(s):  
V.V. Petryakov
Keyword(s):  
Physical Properties ◽  
Spirulina Platensis ◽  
Laboratory Conditions

Some physical properties that affect the rate of diffusion of oxygen into silage

1983 ◽  
Vol 100 (3) ◽  
pp. 601-605 ◽  
Author(s):  
D. V. H. Rees ◽  
E. Audsley ◽  
M. A. Neale
Keyword(s):  
Carbon Dioxide ◽  
Physical Properties ◽  
Laboratory Conditions

SUMMARYExperiments are described which study the effect of density and chop length on the rate of diffusion of oxygen into silage and equations are presented which enable the rate of diffusion to be calculated under laboratory conditions. The concept of zero porosity is also discussed and methods of calculating the density at which it occurs are given. The effect of carbon dioxide on the rate of diffusion is also discussed.

Mechanical and Physical Properties of Straw Bales

2013 ◽  
Vol 649 ◽  
pp. 250-253 ◽  
Author(s):  
Petr Konečný ◽  
Jiří Teslík ◽  
Michal Hamala
Keyword(s):  
Physical Properties ◽  
Material Properties ◽  
Modulus Of Elasticity ◽  
Building Material ◽  
Deformation Behavior ◽  
Deformation Characteristics ◽  
Empirical Knowledge ◽  
Laboratory Conditions ◽  
Mechanical And Physical Properties ◽  
Ecological Building

Straw bales can be used as a relatively cheap and ecological building material for buildings. Design of straw buildings is currently based on empirical knowledge although it would be very helpful to have more information about material properties for designing and realization of straw bales houses. Article discuses load - deformation behavior of straw bales in laboratory conditions and evaluate the modulus of elasticity of local straw bales. Deformation characteristics of straw bales can be very useful for the design of straw buildings.

On the Sound, Produced by a Coin, Rolling in a Balloon

2021 ◽  
Vol 30 (6) ◽  
pp. 606-612
Author(s):  
Denitsa Vasileva ◽  
Keyword(s):  
Physical Properties ◽  
Laboratory Conditions ◽  
The One

Balloons may be a thing children love playing with, but they also have different interesting physical properties such as the sound that is produced when something is put inside a balloon. The phenomenon of interest of this article is the one of gently rolling a coin in a balloon and exploration of the sound produced by this movement. It turns out that when a coin with edges is put in a balloon and is being rolled a buzzing sound is produced which varies in frequencies depending on the count of edges of the coin. This can be observed in non-laboratory conditions. Not many experiments have been conducted to explore this phenomenon.

Selected properties of particleboard made of raspberry Rubus idaeus L. lignocellulosic particles

2019 ◽  
Vol 105 ◽  
pp. 113-124
Author(s):  
ANITA WRONKA ◽  
GRZEGORZ KOWALUK
Keyword(s):  
Physical Properties ◽  
Bending Strength ◽  
Fractional Composition ◽  
Strength Criterion ◽  
Rubus Idaeus ◽  
Raw Material ◽  
Laboratory Conditions ◽  
Mechanical And Physical Properties ◽  
European Standards

Selected properties of particleboard made of raspberry Rubus idaeus L. lignocellulosic particles. The aim of the research was to confirm the possibility of using lignocellulosic particles of raspberry Rubus idaeus L. stalks as an alternative raw material in particleboard technology. Within the scope of work, it was to produce particleboards from raspberry lignocellulosic particles in laboratory conditions, and to investigate selected mechanical and physical properties of the produced boards. In addition to the aforementioned tests, the characterization of the lignocellulosic raw material used in the tests (density, bark share, fractional composition) was carried out. The tests have shown that it is possible to produce the furniture particleboards with use the lignocellulosic particles of raspberry Rubus idaeus L. To meet the requirements of the European standards for furniture panels, such particleboards must contain less than 50% of raspberry particles with density 650 kg/m3 (due to the bending strength criterion).

scholarly journals The constitution and formation of bleaching powder

1935 ◽  
Vol 151 (872) ◽  
pp. 141-167 ◽  
Author(s):  
Charles William Bunn ◽  
L. M. Clark ◽  
I. L. Clifford ◽  
William Lawrence Bragg
Keyword(s):  
Physical Properties ◽  
Calcium Hydroxide ◽  
Calcium Chloride ◽  
Free Calcium ◽  
Calcium Hypochlorite ◽  
Bleaching Powder ◽  
Laboratory Conditions ◽  
The Subject

"Bleaching powder" is made by the action of chloride gas on calcium hydroxide, the reaction being essentially: 2Ca(OH) 2 + 2Cl 2 → Ca(OCl) 2 + CaCl 2 + 2H 2 O. The constitution of the solid formed in this way has been the subject of investigation and speculation for many years, since its properties are not those to be expected of a mixture formed according to the above equation. In the first place, the reaction represented by the above equation never goes to completion; commercial bleaching powder usually contains 15-25% of calcium hydroxide and only about 35% chlorine available for oxidation; while even under special laboratory conditions it is extremely difficult to reduce the calcium hydroxide content below 5%. Secondly, the physical properties of bleaching powder are not those of a simple mixture of calcium hypochlorite, calcium chloride and unreacted calcium hydroxide; for instance, ordinary bleaching powder is not markedly deliquescent, and therefore does not contain free calcium chloride.In the account which follows, no attempt is made to summarize the whole of the previously published work; references are given only to publications which appear to have immediate connection with the issues raised here.

scholarly journals Laboratory tests of the hydraulic pump operating load with monitoring of changes in the physical properties

2021 ◽  
Vol 54 (3-4) ◽  
pp. 243-251
Author(s):  
Lubomir Hujo ◽  
Jozef Nosian ◽  
Marcin Zastempowski ◽  
Jan Kosiba ◽  
Jerzy Kaszkowiak ◽  
...  
Keyword(s):  
Physical Properties ◽  
Present Article ◽  
Water Concentration ◽  
Hydraulic Fluid ◽  
Efficiency Change ◽  
Hydraulic Pump ◽  
Laboratory Conditions ◽  
A Value ◽  
Operating Load ◽  
Agricultural Tractors

The present article deals with the physical properties monitoring of the transmission-hydraulic fluid, and changes of those properties due the operating load of the hydraulic pump in laboratory conditions. Tests of the transmission-hydraulic fluid were performed in laboratory conditions with the simulation of the operating load, so as to simulate the real conditions under which hydraulic circuit of the agricultural tractors operates. The universal transmission-hydraulic fluid was subjected to analysis, where the samples of the fluid were taken sequentially according to the chosen methodology at intervals of 250 and 500 h. The results of the present article include the evaluation of the physical properties of the fluid and the flow efficiency change of the hydraulic pump after 250 and 500 h of operation, while simulating the operation load. Based on a laboratory test, we found that after working for 500 h, the dynamic viscosity of the examined hydraulic fluid at 40°C decreased by 2.92 mPa.s and at 100°C decreased by 0.64 mPa.s. When determining the kinematic viscosity of the hydraulic fluid after working for 500 h, we recorded its decrease, namely, at a temperature of 40°C by a value of 3.37 mm2/s and at a temperature of 100°C, its value decreased by 0.77 mm2/s. In the analysis of the test oil samples, we found that the level of water contamination of the hydraulic fluid decreases with increasing number of hours worked. Specifically, the water concentration in the hydraulic fluid decreased by 0.031%. At the same time, we recorded a slight decrease in the flow efficiency of the hydraulic pump, specifically by a value of 0.03% after 500 h worked. After working 500 h, we found that the range of abrasion particles in the transmission-hydraulic fluid is within the prescribed range, which is determined by the standard D6595-00.

scholarly journals EQUIPMENT TO ADMINISTER IN-DEPTH AMENDMENTS ON LAND AFFECTED BY SALINISATION

2021 ◽  
pp. 9-22
Author(s):  
Marcel Bularda M., ◽  
Nicoleta Ungureanu ◽  
Simona Istricioaia ◽  
Radu Ciuperca ◽  
Paul Marius Mitrache
Keyword(s):  
Physical Properties ◽  
Functional Model ◽  
Soil Conditions ◽  
Laboratory Conditions

This paper presents the results obtained regarding the realization of a functional model of equipment for managing in-depth amendments on salted lands and the results regarding the effect of the work performed in three soil conditions. At the same time, the physical properties of the amendment used (phosphogypsum), determined in laboratory conditions, in order to know the problems that may occur during the application work, are presented.

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