scholarly journals Studies on antagonism.―I. The effect of the presence of salts of monovalent, divalent, and trivalent kations on the intake of calcium and ammonium ions by potato tuber tissue

1933 ◽  
Vol 112 (778) ◽  
pp. 451-472 ◽  
Keyword(s):  
Chemical Analysis ◽  
Physical Properties ◽  
Absorption Rate ◽  
Initial Rate ◽  
Final Position ◽  
Ammonium Ions ◽  
Conductivity Method ◽  
Tuber Tissue ◽  
Rate Of Absorption ◽  
The Subject

The intake of salts by storage tissues has been worked out at some length by Stiles using both the conductivity method and chemical analysis to determine the alteration in concentration of the solution supplied to the tissue. Results of these investigations as well as those of other workers on the subject point to the fact that salts are not taken in as such, but as their constituent ions, which may be absorbed to a very different degree. Stiles (1924) found that the ions were absorbed comparatively rapidly at first, for a period lasting up to 10 hours, after which there was a gradual falling off in the absorption rate so that after 24 hours absorption was only proceeding very slowly. It was also suggested that the initial rate of absorption depended more on the physical properties of the ions, such as their mobility and the coefficients of diffusion of their salts, and bore, it was found, no relationship to the final position of equilibrium (Stiles, 1919).

scholarly journals Recycling of Cigarette Butts in Fired Clay Bricks: A New Laboratory Investigation

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 790 ◽  
Author(s):  
Halenur Kurmus ◽  
Abbas Mohajerani
Keyword(s):  
Absorption Rate ◽  
Initial Rate ◽  
Microstructural Analysis ◽  
Toxic Waste ◽  
Firing Process ◽  
Dry Density ◽  
Clay Bricks ◽  
Cigarette Butts ◽  
The World ◽  
Rate Of Absorption

Cigarette butts (CBs) are the most commonly littered waste material in the world. It is estimated that over 5.7 trillion cigarettes are consumed worldwide each year. Consequently, millions of tonnes of highly toxic waste are contaminating the environment. CBs are composed of cellulose acetate filters—a polymer with poor biodegradability—and which, depending upon the environmental conditions, can take many years to decompose. In this study, fired clay bricks were manufactured with 0.5%, 1%, 1.5%, and 2% CBs by mass and tested against control bricks with 0% CBs. The results revealed a decrease in compressive strength from 48.6 MPa for 0% CB content bricks to 30.8 MPa for 1% CB content bricks, and a decrease in dry density with the increase in CB content, from 2114 kg/m3 for the control bricks to 1983 kg/m3 and 1969 kg/m3 for 1% and 2% CB content bricks. The highest value of water absorption appeared for 2% CB content bricks, which reached an absorption rate of 13.1% compared to 9% for the control bricks. The energy required during the firing process was calculated with a saving of up to 10.20%, for bricks incorporating 1% CBs. The thermal conductivity of the samples showed a reduction of 17% from 1.078 to 0.898 W m−1·K−1 with the addition of 1% CBs. In addition, the manufactured bricks were tested for efflorescence, an initial rate of absorption (IRA), microstructural analysis, and shrinkage. A life-cycle assessment (LCA) is recommended to analyze the environmental impacts of bricks incorporating CBs.

ALGOMA AR225

Alloy Digest ◽  
2003 ◽  
Vol 52 (12) ◽  
Keyword(s):  
Carbon Steel ◽  
Chemical Analysis ◽  
Physical Properties ◽  
Carbon Content ◽  
Brinell Hardness ◽  
Low Cost ◽  
Heat Treating ◽  
Rolled Plate ◽  
High Carbon ◽  
High Carbon Content

Abstract Algoma AR225 is a carbon steel developed primarily to supply a low-cost material for high-abrasion applications. It is furnished in the form of as-rolled plate with a relatively high carbon content (0.35-0.45%). AR-225 is sold on the basis of chemical analysis only; the number 225 signifies the approximate Brinell hardness. On thicknesses one-half inch and over, this Brinell value may be lower than 225 because of higher finishing temperatures. This datasheet provides information on composition, physical properties, hardness, and elasticity. It also includes information on forming, heat treating, machining, and joining. Filing Code: CS-138. Producer or source: Algoma Steel Corporation Ltd.

scholarly journals IX. The electric conductivity of nitric acid

1898 ◽  
Vol 191 ◽  
pp. 365-398 ◽  
Keyword(s):  
Nitric Acid ◽  
Physical Properties ◽  
Nitrous Acid ◽  
Internal Resistance ◽  
The Other ◽  
Reasonable Degree ◽  
Mineral Acids ◽  
Artificial Illumination ◽  
The Subject ◽  
Deep Green

Of the commoner mineral acids the chemical changes of Nitric Acid, from their evident complexity, have formed the subject of numerous memoirs, while those of sulphuric acid, from their assumed simplicity, have been to some degree neglected; on the other hand, the physical properties of the latter have been studied with considerable elaboration, while those of the former have been passed over, doubtless on account of the corrosive nature of the acid and the difficulty of preparing and preserving it in a reasonable degree of purity. Further, with certain exceptions, the alterations in physical properties induced by the products of reduction, be they nitrogen peroxide or nitrous acid, either singly or conjointly, have attracted but little attention, though it is a common matter of observation that the current intensity of a Grove’s or other cell containing nitric acid remains constant, even though the fuming acid, originally colourless or red, has become of a deep green tint. It is more than probable that of the factors of Ohm’s law, both the E. M. F. and internal resistance are continually varying. At the earliest stages of the enquiry it was found that the passage of a few bubbles of nitric oxide gas into a considerable volume of nitric acid produced an alteration of one percent, in the resistance, and the same result could be effected to a less degree by exposure to sunlight, and to a still less degree by exposure to artificial illumination. Therefore, we determined to investigate the alterations of conductivity produced by changes of concentration and temperature in samples of acid purified with necessary precautions, more especially as former workers upon the subject have either used samples of acid confessedly impure, or have been silent as to any method of purification, or have adopted no special care in dealing with a substance so susceptible of polarisation.

Function curve of the membranes that regulate amniotic fluid volume in sheep

2005 ◽  
Vol 289 (1) ◽  
pp. H146-H150 ◽  
Author(s):  
Job Faber ◽  
Debra Anderson ◽  
Roger Hohimer ◽  
Qin Yang ◽  
George Giraud ◽  
...  
Keyword(s):  
Amniotic Fluid ◽  
Absorption Rate ◽  
Plasma Renin ◽  
Fluid Volume ◽  
Natural Rate ◽  
Fetal Plasma ◽  
Amniotic Fluid Volume ◽  
Urine Production ◽  
Rate Of Absorption ◽  
Vascular Catheters

Seven singleton 120-day fetal lambs were prepared with a shunt from the lung to the gastric end of the esophagus, a bladder catheter, and multiple amniotic fluid and vascular catheters. The urachus was ligated. Beginning 7 days later, amniotic fluid volumes were determined by drainage, followed by replacement with 1 liter of lactated Ringer (LR) solution. Urine flow into the amnion was measured continuously. In 14 of 27 experiments, amniotic fluid volumes were determined again 2 days after the inflow into the amnion had consisted of urine only and in 13 experiments after the inflow of urine had been supplemented by an intraamniotic infusion of LR solution. Intramembranous absorption was calculated from the inflows and the changes in volume between the beginning and end of each experiment. The relations between absorption rate and amniotic fluid volume, the “function curves,” were highly individual. Urine production during the infusion of LR solution did not decrease, fetal plasma renin activity decreased ( P < 0.001), and amniotic fluid volume increased by 140% [SE (27%), P < 0.005], but the increase in the amniochorionic absorption rate of 411% [SE (48%), P < 0.001] was greater ( P < 0.005) than the increase in volume. Each of the seven fetuses was proven capable of an average intramembranous absorption rate that exceeded 4.5 liters of amniotic fluid per day. During the infusion of LR solution, the increase in the rate of absorption matched the rate of infusion (both in ml/h), with a regression coefficient of 0.75 ( P < 0.001). Thus, even for large amniotic fluid volumes, volume is not limited by the absorptive capacity of the amniochorion, and, at least in these preparations, the position of the function curve and not the natural rate of inflow was the major determinant of resting amniotic fluid volume.

XIV. Researches into the molecular constitution of the organic bases

1851 ◽  
Vol 141 ◽  
pp. 357-398 ◽  
Keyword(s):  
Physical Properties ◽  
Royal Society ◽  
General Outline ◽  
Organic Bases ◽  
History Of ◽  
The Subject ◽  
Molecular Constitution

About twelve months ago I had the honour of presenting to the Royal Society an account of a series of researches into the molecular constitution of the volatile organic bases: at present I beg to submit to the consideration of the Society the history of a new group of alkaloids, which, although intimately connected with the former by their origin, differ from them altogether by their properties, and especially in not being volatile . The members of this new group of alkaloids are so numerous, their deportment is so singular, and their derivatives ramify in so many directions, that I have not as yet been able to complete the study of these substances in all their bearings; nor is it my intention to go fully into the chemistry of the subject in the present com­munication, my object being merely to establish the existence of these bodies, and to give a general outline of their connection with the volatile bases, and of their most prominent chemical and physical properties, reserving a detailed description of their salts and derivatives to a future memoir.

scholarly journals Influences of Temperature on the Conversion of Ammonium Tungstate Pentahydrate to Tungsten Oxide Particles with Controllable Sizes, Crystallinities, and Physical Properties

2018 ◽  
Vol 16 (2) ◽  
pp. 124 ◽  
Author(s):  
Asep Bayu Dani Nandiyanto ◽  
Heli Siti Halimatul Munawaroh ◽  
Tedi Kurniawan ◽  
Ahmad Mudzakir
Keyword(s):  
Physicochemical Properties ◽  
Physical Properties ◽  
Undergraduate Students ◽  
Tungsten Trioxide ◽  
Model Material ◽  
Effect Of Temperature ◽  
Water Molecules ◽  
Ammonium Ions ◽  
Experimental Procedure ◽  
Ammonium Tungstate

The purpose of this study was to investigate influences of temperature on the conversion of ammonium tungstate pentahydrate (ATP) powder to tungsten trioxide (WO3) particles with controllable sizes, crystallinities, and physicochemical properties. In this study, we used a simple thermal decomposition method. In the experimental procedure, we explored the effect of temperature on the physicochemical properties of ATP by testing various heating temperatures (from 100 to 900 °C). The heated ATP samples were then characterized by a physical observation (i.e. color) and various analysis methods (i.e. a thermal gravimetric and differential thermal analysis, infrared spectroscopy, an X-ray diffraction, and a scanning electron microscope). Experimental results showed that increases in temperature had an impact to the decreases in particle size, the change in material crystallinity, and the change in physical properties (e.g. change of color from white, orange, to yellowish green). The relationships between the reaction temperatures and the physicochemical properties of the ATP were also investigated in detail along with the theoretical consideration and the proposal of the WO3 particle formation mechanism. In simplification, the phenomena can be described into three zones of temperatures. (1) Below 250 °C (release of water molecules and some ammonium ions).; (2) At 250-400 °C (release of water molecules and ammonium ions, restructurization of tungsten and oxygen elements, and formation of amorphous tungsten trioxide). (3) At higher than 400 °C (crystallization of tungsten trioxide). Since ATP possessed reactivity on temperature, its physicochemical properties changing could be observed easily, and the experimental procedure could be done easily. The present study will benefit not only for “chemistry and material science” but also potentially to be used as a model material for explaining the thermal behavior of material to undergraduate students (suitable used for a class and laboratory experiment and demonstration).

scholarly journals Nahrwan Clays Study for Brick Industry

2008 ◽  
Vol 5 (4) ◽  
pp. 538-544
Author(s):  
Baghdad Science Journal
Keyword(s):  
Compressive Strength ◽  
Chemical Analysis ◽  
Moisture Content ◽  
Physical Properties ◽  
Clay Brick ◽  
Quaternary Sediment ◽  
Physical Test ◽  
Class A ◽  
Clay Deposits ◽  
Depth Ranges

Nahrawan clay deposits lies in Diyala governorate , 65 Km, NE of Baghdad , according to the previous work in this field, in which they study the reserve belong to category of investigation ( C2 & C1 ) , we choice the proper area to investigation of category (B) with drill net( 200x 200m ) to rise the amount of reserve. The investigation work included drilling (116) boreholes of total depth ranges from (10.0-12.55m) , showed mainly clayey and silty deposits with little sand , and the typical borehole (648) represents all types of sediment in the area , and most of boreholes without sandy deposits , and all of these deposits is Quaternary sediment which is consist of two main sedimentary cycles ( the Pleistocene & Holocene ) . Chemical analysis for (343) samples were done , and physical test carried on ( 143 ) samples , and all show suitable properties for clay brick industry . the area of investigation covered ( 5.200.000 m2) involving ( 620.000 m2 ) containing soluble salt more than ( 3.5%) , which was separated from the total area , so the residual (4.580.000m2 ) had been taken to calculate the reserve , with depth of ( 10.76m) for the industrial clay bed . The reserve calculations depended on the following chemical & physical Properties: The chemical analysis shows that , CaO ( 16.53%) MgO ( 4.65% ) , SO3 ( 1.42%) , T.S.S. (2.42%) , the physical properties are unfired properties Which contains Bulk density ( 2.09gm/cm3) , moisture content (20.95%) , linear dry shri. (7.63%) , and fired properties which contain water absorption (18.8%) , linear shri. (0.8%) volume shri. (2.212% ) , compressive strength ( 468.606Kg/cm2) . So the reserve of category (B) is ( 49.280. 800 m3 ) or (102.966.000 Ton) the physical test showed that the brick classified into class (A-B) .

scholarly journals V. On the chemical analysis of the contents of the thoracic duct the human sub­ject

1842 ◽  
Vol 132 ◽  
pp. 81-85 ◽  
Keyword(s):  
Chemical Analysis ◽  
Thoracic Duct ◽  
Human Subject ◽  
The Body ◽  
Old Bailey ◽  
The Subject

The contents of the thoracic duct in the human subject having never been obtained in sufficient quantity for the purposes of chemical analysis, I resolved to avail myself of an opportunity which lately presented itself in the execution of a criminal at the Old Bailey. Through the kindness of Messrs. Macmurdo and Holding, the medical officers of Newgate, and with the assistance of my friends Mr. Hilton and Mr. Samuel Lane, I was enabled to commence operating upon the body one hour and a quarter after death, and before it had become cold, although the thermometer stood considerably below 32° Fahr., and the body had been exposed on the scaffold during one hour. The subject was muscular and of the middle height, and the prisoner had not become emaciated during his confinement in jail. On the evening preceding his execution, he had partaken of some supper, consisting of about 2 oz. of bread and 4 oz. of meat; and the next morning, he drank two cups of tea, and ate a piece of toast made from the quarter of a round of a quartern loaf, and about a quarter of an inch in thick­ness. This breakfast was taken at seven o’clock A. M., one hour before death. He swallowed a glass of wine just before mounting the scaffold.

An Analysis of Students Problem To Pronounce Aspirated /P/, /T/, /K/ at Initial Position of English Words

2020 ◽  
Vol 4 (3) ◽  
pp. 92-98
Author(s):  
Widya Juli Astria
Keyword(s):  
Research Design ◽  
Initial Position ◽  
English Department ◽  
Final Position ◽  
The Third ◽  
The Subject ◽  
Learning English

The purpose of this research was to analyze the third semester students’ problem in learning English basic sounds pronunciation. The research design was case study. The data were collected by recording the students’ pronunciation. The subject of the research were the third Semester Students of English Department at Universitas Ekasakti). The result of the research was found that Each aspirated /p/, /t/, /k/ have two allophones, [ph] and [p], [th] and [t], [kh] and [k]. Then, all instances of [ph] occured immediately before a stressed vowel. It can be said that the following rule: /p/ becomes [ph] when it occured before a stressed vowel or initial position of English words. Moreover, aspirated /p/, /t/, /k/ sounds were really pronounced in two different ways. First, when these sounds came at the beginning of the word they are always followed by a puff of breath. Second, if aspirated /p/, /t/, and /k/ occur at the end of final position of English words, it is not necessary to pronounce them by following a puff of breath. In following there is a chart of aspirated /p/, /t/, /k/ sounds at initial position of English words

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