A New Rubber Particle Count in Hevea Latex

1936 ◽  
Vol 9 (4) ◽  
pp. 644-647
Author(s):  
Earle E. Langeland
Keyword(s):  
Original Work ◽  
Rubber Particle ◽  
Fundamental Property ◽  
The Other ◽  
Rubber Content ◽  
Microscopic Method ◽  
Particle Count ◽  
Rubber Particles ◽  
The One

Abstract SO MUCH confusion has grown up in the literature concerning the number of rubber particles in Hevea latex that at the present time there exists a thousandfold error in the currently published reports (1, 3, 8) of the one original determination of this number. Harries (4), Hauser (5), and Noble (8), each reporting the original work of Henri (6), give a count of 50,000,000 particles per cubic centimeter of latex, Harries not specifying the concentration, while Hauser and Noble indicate it to have been 8.7 per cent solids. On the other hand, Dubosc and Luttringer (2), also reporting the work of Henri, record a count of 50,000,000 particles per cubic millimeter in latex of unspecified concentration. The original paper of Henri (6) reported that he had found an average of 50,000,000 particles per cubic millimeter of latex having a specific gravity of 0.973 and containing 8.7 grams of solids per 100 cc. Preliminary counts undertaken by the author with a view to developing a rapid microscopic method for the determination of the dry rubber content of latex indicated that the results of Henri were considerably low. Since the number of microscopically visible particles is a fundamental property of latex, it was felt that a redetermination of this number would be of value.

scholarly journals Determination of the Height of Hard X-Ray Sources in the Solar Atmosphere by Measurement of Photospheric Albedo Photons

1975 ◽  
Vol 68 ◽  
pp. 239-241
Author(s):  
John C. Brown ◽  
H. F. Van Beek
Keyword(s):  
Solar Atmosphere ◽  
The Other ◽  
X Ray ◽  
Theoretical Predictions ◽  
Source Models ◽  
The One

SummaryThe importance and difficulties of determining the height of hard X-ray sources in the solar atmosphere, in order to distinguish source models, have been discussed by Brown and McClymont (1974) and also in this Symposium (Brown, 1975; Datlowe, 1975). Theoretical predictions of this height, h, range between and 105 km above the photosphere for different models (Brown and McClymont, 1974; McClymont and Brown, 1974). Equally diverse values have been inferred from observations of synchronous chromospheric EUV bursts (Kane and Donnelly, 1971) on the one hand and from apparently behind-the-limb events (e.g. Datlowe, 1975) on the other.

Augustus and the Senate: 23 B.C.

Antichthon ◽  
1985 ◽  
Vol 19 ◽  
pp. 57-67 ◽  
Author(s):  
W.K. Lacey
Keyword(s):  
The Other ◽  
The One ◽  
Res Publica

While the exact meaning of Res Gestae 34, the powers of Augustus at various moments in his principate, and the significance of his auctoritas have been extensively argued, more practical questions about how his political arrangements might have been set into action have not generally excited much interest. In 1974 I put forward a suggestion about how the so-called first settlement of 27 B.C. came about. It was, in brief, that Octavian, as he then was, used the traditional consular mechanisms, and proposed for debate in the Senate a motion, de provinciis consularibus, and this explains why, on the one hand, the result of the debate was that he had provinces allocated to him, and, on the other, claims could be made that the res publica was restored, because one of the things which characterized res publica (as distinct from dictatorship or triumviral rule) was that the determination of who should command which army stationed in the provinces now lay, ostensibly at least, with the publicum consilium, the Senate.

Table II : Quantitative determination of carbonyl compounds at different odour sources (concentrations in ppb) Rendering plant Gelatine plant neighbourhood neighbourhood Formaldehyde 40 16 Acetaldehyde 39 24 Acetone 36 73 Prcpanal 10 -Isobutyraldehyde 10 30 Pentanal 15 19 Hexanal 3.52 Heptanal 12.5 Octanal 10.5 Nonanal 1 2 acids (figure 7). However extractions always involve a serious decrease in sensitivity, while evaporation of the extract produces a solution in 0.1-0.5 ml of solvent, and only 1 pi of it can be brought in the gas chromatograph. Therefore work is in progress to enhance sensitivity by converting acids in­ to halogenated derivatives, which can be GC-analysed with the more sensitive electron-capture detector. For thiols a similar procedure is investigated as with aldehydes. One possibility is absorption of thiols in an alkaline solution and reaction with 2,4-dinitrochlorobenzene, yielding 2,4-dinitrofenylsulfides, which are analysed by HPLC (9). Sane improvements on removal of reagents at the one hand and on separation of sane by-products on the other hand have to be achieved in order to in­ crease the sensitivity with another factor of ten. 5. CONCLUSION The actual scope and limitations of chemical analysis of odour show that all problems can be tackled as far as emission is concerned. For iititiission measurements seme progress is necessary, but there is no essential reason why chemical analysis would be unable to attain the desired sensitivity for all types of odorants. There is no doubt that in a few years the last dif­ ficulties will be solved. In order to achieve real control of odour nui­ sance, automatic measurement is necessary on a long time basis. There again seme technical development is to be expected. Does this mean that machines are going to decide if an odour is pre­ sent or not? By no means, while the population will always be the reference, and psychophysical measurements will be necessary to make chemical analysis possible.

1986 ◽  
pp. 171-171
Keyword(s):  
Chemical Analysis ◽  
Quantitative Determination ◽  
Alkaline Solution ◽  
Automatic Measurement ◽  
The Other ◽  
Long Time ◽  
Time Basis ◽  
The One ◽  
By Products

scholarly journals XIII. Revision of the atomic weight of gold

1889 ◽  
Vol 180 ◽  
pp. 395-441 ◽  
Keyword(s):  
Royal Society ◽  
Original Work ◽  
Atomic Weight ◽  
The Other ◽  
Organic Substances ◽  
Modern Methods ◽  
Gold Compounds ◽  
Chemical Section

Until lately gold ranked among the elementary substances of which the general properties had been well ascertained, but in regard to the atomic weights of which our knowledge was least satisfactory. That this constant should be determined as accurately as possible for gold was desirable in view of its bearing on the precise place assigned the metal in the “periodic” classification of the elements based on the ideas of Newlands, Odling, Mendelejeff, and L. Meyer. Furthermore, an exact know­ ledge of the atomic weight of gold might be conveniently applied in the determination of the atomic weights of some of the other elements. A practical laboratory reason for desiring to possess a trustworthy value for this constant was also presented by the facility with which gold compounds of many organic substances may be prepared, and the ease with which their composition may be ascertained by simple ignition in the air and weighing of the residual gold, the results leading to a knowledge of molecular composition when the atomic value of the weight of the metal obtained is assumed to be known. For the last three years and a half I have been occupied, during a large part of such time as has been available for original work, in devising and carrying out experiments aiming at the redetermination of the constant in question. The difficulties met with have been greater than were at first looked for, and have led to much time and labour being consumed in attempts to overcome them. About two years ago, when this work was already well under way but still in progress, there appeared the results of experiments aiming at the same end, by Kruss in Germany and by Thorpe and Laurie in England—experiments made with the care and accu­racy of modern methods, and apparently deserving of much confidence. My own work, however, was continued, as we cannot have too many careful independent determinations of atomic weights by different workers, and as I had used to a con­siderable extent other procesess than those on which the newly published determina­tions were based, while the chemists named had employed, in the main, one and the same method. A preliminary notice of my work was read in the Chemical Section of the British Association at the Manchester meeting of 1887. The details of my experiments and the results which I have reached are now laid before the Royal Society.

Microturbidimeter for Determination of Rubber Content of Latex

1931 ◽  
Vol 4 (4) ◽  
pp. 601-611
Author(s):  
S. D. Gehman ◽  
J. S. Ward
Keyword(s):  
Particle Size ◽  
Rubber Content ◽  
Mean Particle Size ◽  
Rubber Particles ◽  
Color Filters

Abstract It is desirable to devise a method for determining the dry rubber content of latex which will be both more rapid than the two trial coagulation methods and more precise than the hydrometric method. The turbidity of latex, depending upon the volumetric number and size of the suspended rubber particles, offers a satisfactory criterion for the determination of the rubber content of latex. A microturbidimeter, herein described, has been adapted to such determinations. It permits more rapid determinations of the rubber content than the two trial coagulation methods. Its precision is less than the lengthy trial coagulation method, involving coagulation, creping, and drying, but is probably greater than that of the shortened trial coagulation method involving only coagulation and creping. Its precision is approximately 1 per cent rubber in 35 per cent latex. The turbidity of latex obeys the turbidity-dilution law for rubber-content values less than 15 per cent. The use of color filters, transmitting the shorter wave lengths of light, minimizes the effects of a difference in the effective mean particle size of different kinds of latex.

scholarly journals XXII. On the extensive atmosphere of Mars

1831 ◽  
Vol 121 ◽  
pp. 417-422 ◽  
Keyword(s):  
The Other ◽  
Astronomical Observations ◽  
Royal Observatory ◽  
Formed Part ◽  
The One

That several of the planets as well as that which we inhabit are surrounded by atmosphere, astronomical observations have long since established; the extent, however, to which in particular planets such atmospheres are diffused, is as yet not satisfactorily determined. The former rests principally upon phenomena observed on the planets’ discs, whilst the latter derives its support chiefly from those detected at or near their respective limbs. Every night, nay almost every hour, may give us indication of the one, whilst years are sometimes necessary, as in the case of planets unattended by satellites, to help us to the other; thus the hypothesis of the extensive atmosphere of Mars derives its origin from the observations of Cassini and Roëmer, and has stood more than a century and a half without refutation or support. The observations to which I allude formed part of a series undertaken for the determination of the parallax of Mars, and are recorded in the Mémoires de l’Académie des Sciences. Cassini’s were made at Briare and at La Charité sur Loire; whilst Roémer’s was obtained at the Royal Observatory of Paris.

Serological characteristics of Streptomyces species using cell wall immunizing antigens

1970 ◽  
Vol 16 (2) ◽  
pp. 107-115 ◽  
Author(s):  
Gerald R. Taylor ◽  
Rufus K. Guthrie ◽  
Elwood B. Shirling
Keyword(s):  
Cell Wall ◽  
Morphological Characteristics ◽  
The Other ◽  
Streptomyces Species ◽  
Dichotomous Key ◽  
Specific Antisera ◽  
Combination Of Methods ◽  
The One ◽  
Taxonomic Studies

A dichotomous key for determination of serological groups among Streptomyces is described. This key is limited in that only seven specific antisera are used for testing. The utility and reliability of the application of this key were tested and compared to the results of previous taxonomic studies reported on the basis of biochemical and morphological characteristics of these organisms. Results indicate the desirability of using a combination of methods including serological characteristics on the one hand, and biochemical–morphological characteristics on the other, to increase the reliability of taxonomic studies.

scholarly journals IX. Remarks concerning the Natural-Historical Determination of Diallage

1826 ◽  
Vol 10 (1) ◽  
pp. 127-147
Author(s):  
W. Haidinger
Keyword(s):  
Fixed Point ◽  
Natural History ◽  
Distinct Species ◽  
The Other ◽  
Accurate Information ◽  
External Appearance ◽  
Slight Degree ◽  
The One

The following paper contains the results of a series of inquiries, which lead to the conclusion, that the mineral called Smaragdite by Saussure, does not form a species of its own; but that this name has been given to a compound of certain varieties of two distinct species, Augite and Hornblende, the natural-historical species of paratomous and hemiprismatic Augite-spar.Owing in part to the slight degree of resemblance prevailing among its varieties, the authors who have described them differ so essentially in opinion, that I am obliged to go into various details, both respecting the external appearance of the mineral itself, and of the opinions of mineralogists, in order to afford a correct view of the natural-historical species, to which these varieties belong, since this is the basis upon which every system, and, indeed, all accurate information in natural history, is founded, and the fixed point to which the one and the other must be referred.

Determination of Enemy Character of Corporations

1930 ◽  
Vol 24 (2) ◽  
pp. 310-336 ◽  
Author(s):  
Ralph A. Nohem
Keyword(s):  
The Other ◽  
Separate Entity ◽  
Entity Theory ◽  
Long Period ◽  
Corporate Entity ◽  
Sovereign Authority ◽  
The Subject ◽  
The One ◽  
Independent Person

Much controversy has raged for a long period of time over the precise nature of what Wormser refers to as the “anatomy” of a corporation. Wormser himself defines a corporation as a “group of one or more persons authorized by sovereign authority to act as a unit and a personality in the eye of the law.” The definition indicates, on the one hand, that the act of incorporation creates a new person or entity, on the other that this new entity is in fact composite, made up of one or more pre-existing entities. The question arises, at what times will the court regard the corporate entity, and at what times will it look to the real persons who compose it ? A key to the solution of the problem is offered by Lord Mansfield. “A fiction of law shall never be contradicted so as to defeat the end for which it was invented, but for every other purpose it may be contradicted.” By the separate entity theory is meant that a corporation is to be regarded as an entity separate and apart from its corporators and that it is to be treated like any other independent person. That this is the theory of corporations generally accepted by the courts need hardly be proved. It will only be noted that the ruling English case on the subject is that of Salomon and Co. v. Salomon. In his opinion in that case Lord Halsbury said: “Once the company is legally incorporated it must be treated like any other independent person.”

scholarly journals Element-for-Element Replacement? Beware! There Might Be a "No-Entry" Sign

2002 ◽  
Vol 45 (4) ◽  
pp. 622-627
Author(s):  
Kazem Lotfipour-Saedi
Keyword(s):  
The Other ◽  
Language System ◽  
Direct Route ◽  
The One ◽  
The Relationship ◽  
Replacement Operation

Abstract Various definitions have been offered for translation, each assuming a different orientation to the nature of meaning and language but all sharing the notion of replacement of one sort or another. The commonsensically perceived framework of translation operation is also basically founded upon the notion of replacement, mostly leading to the illusion that translation is just a matter of replacing SL elements by TL ones. But due to the uniqueness of each language system on the one hand and the non-isomorphic nature of the relationship between form and meaning across language on the other, this replacement operation faces challenging problems. This paper argues that there is no direct route in this operation and the replacement becomes possible only through the determination of the value of the elements to be replaced.

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