scholarly journals The arc spectrum of palladium, its Zeeman effect and spectral type

1925 ◽  
Vol 109 (750) ◽  
pp. 369-384 ◽  
Keyword(s):  
Atomic Number ◽  
Spectral Type ◽  
Periodic Table ◽  
Zeeman Effect ◽  
Atomic Weight ◽  
The Other ◽  
Present Writer ◽  
Vertical Column ◽  
Other Hand ◽  
Cobalt And Nickel

Palladium is a metal occurring in the eighth group of the periodic table of the elements. Of atomic number 46 and atomic weight 106·7, it is a member of the so-called triad—ruthenium, rhodium, palladium. In the vertical column of the table, palladium occupies a position between nickel and platinum. According to the alternation law governing the multiplicities of terms in the line-spectra of the elements, only odd multiplicities are to be expected in the even groups of the table, and vice versa . The numerous spectral regularities which have been discovered in the arc spectrum of iron, belong entirely to triplet, quintet, and septet systems. The arc spectrum of cobalt, on the other hand, has been shown by Walters to contain quartets. This would seem to indicate that the present grouping of these elements is erroneous, and that a division should occur between iron and cobalt, and probably also between cobalt and nickel. The behaviour of elements in the other groups of the table makes it probable that ruthenium and osmium, in the same vertical column, should be in the same group with iron, and that their spectra should be similar and should contain only odd multiplicities. Similarly, rhodium and iridium would be grouped with cobalt, and only terms of even multiplicity should appear in their spectra. The next group would then be nickel, palladium, and platinum, and again odd multiplicities would be expected. An analysis of the spectrum of nickel has been undertaken at the laboratory of the Bureau of Standards in Washington. Some photographs of the Zeeman effect of nickel have been made by the present writer, and the patterns observed indicate that the spectrum of nickel contains triplet terms.

An Overview of the Interdiffusion Studies in Mo-Si and W-Si Systems

2014 ◽  
Vol 354 ◽  
pp. 79-83
Author(s):  
Soumitra Roy ◽  
Soma Prasad ◽  
Aloke Paul
Keyword(s):  
Crystal Structures ◽  
Atomic Number ◽  
Diffusion Coefficients ◽  
Relative Increase ◽  
The Other ◽  
Reactive Diffusion ◽  
Refractory Elements ◽  
Other Hand ◽  
Two Systems ◽  
Diffusion Rates

The growth of phases by reactive diffusion in Mo-Si and W-Si systems are compared. The crystal structures of MSi2 and M5Si3 phases (M = Mo, W) are similar in these two systems. However, the diffusion rates of the components change systematically with a change in the atomic number. Integrated diffusion coefficients in both phases increase with an increasing atomic number of refractory elements i.e. from Mo to W. On the other hand, the ratio of diffusivities of the components decreases. This indicates a relative increase in the diffusion rates of the metal components with increasing atomic number and a difference in defects concentrations in these two systems.

Alice Chaucer and her Husbands

PMLA ◽  
1945 ◽  
Vol 60 (1) ◽  
pp. 24-47
Author(s):  
Marjorie Anderson
Keyword(s):  
The Other ◽  
Present Writer ◽  
Weight Of Evidence ◽  
English History ◽  
Personal Influence ◽  
Other Hand

This paper is written on the assumption that Alice Chaucer was the granddaughter of the poet. That she was the daughter of Thomas Chaucer is easily proved and, despite skillful arguments to the contrary, the weight of evidence seems to the present writer to confirm the belief that Thomas was the son of Geoffrey. This paper is also written because of the assumption of Alice's relation to Geoffrey; her connection with the poet has been the chief reason for this study of her life. But such need not have been the case. Chaucer had no personal influence upon his granddaughter, unless by way of heredity, for their lives did not overlap. She was born four years after the poet's death. On the other hand, she lived to be the wife and widow of three successive men, two of whom were of great military and political prominence in English history; she was the friend and confidante of royalty; she became the mother-in-law of a king's sister. She was, in truth, a figure of sufficient social and political importance in the life of her time to merit consideration on her own account.

VIII. A critical study of spectral series.— Part III. The atomic weight term and its import in the constitution of spectra

1914 ◽  
Vol 213 (497-508) ◽  
pp. 323-420
Keyword(s):  
Periodic Table ◽  
Principal Series ◽  
Atomic Weight ◽  
The Other ◽  
Critical Study ◽  
Spectral Series ◽  
Present Communication ◽  
The Real ◽  
Real Relation ◽  
The One

The doublet and triplet separations in the spectra of elements are, as has long been known, roughly proportional to the squares of their atomic weights, at least whenelements of the same group of the periodic table are compared. In the formulæ which give the series lines these separations arise by certain terms being deducted from the denominator of the typical sequences. For instance, in the alkalies if the p -sequence be written N/D m 2 , where D m = m +μ+α/ m the p -sequence for the second principal series has denominator D—Δ, and we get converging doublets; whereas the constant separations for the S and D series are formed by taking S 1 (∞) = D 1 (∞) = N/D 1 2 and S 2 (∞) = D 2 (∞)= N/(D 1 —Δ) 2 . It is clear that the values of Δ for the various elements will also be roughly proportional to the squares of the atomic weights. For this reason it is convenient to refer to them as the atomic weight terms. We shall denote them by Δ in the case of doublets and Δ 1 and Δ 2 in the case of triplets, using v as before to denote the separations. Two questions naturally arise. On the one hand what is the real relation between them and the atomic weights, and on the other what relation have they to the constitution of the spectra themselves ? The present communication is an attempt to throw some light on both these problems.

6. Physics invades the periodic table

2019 ◽  
pp. 73-84
Author(s):  
Eric R. Scerri
Keyword(s):  
Nuclear Structure ◽  
Atomic Number ◽  
Periodic Table ◽  
Atomic Weight ◽  
Ernest Rutherford ◽  
Frederick Soddy ◽  
The Impact

‘Physics invades the periodic table’ assesses the impact of key discoveries in physics on the understanding of the periodic table. Ernest Rutherford provided evidence for the nuclear structure of atoms, and also determined that the charge of an atom is equal to half its atomic weight. Anton van den Broek linked this principle to the number of protons in a nucleus, thus devising the notion of atomic number. Henry Moseley quantified this principle, and used it to show exactly how many elements would fill the gaps in the periodic table. Radioactive experiments created new forms of elements with different weights but the same charge, which Frederick Soddy identified as isotopes.

Element 72—Hafnium

2013 ◽  
Author(s):  
Eric Scerri
Keyword(s):  
Rare Earth ◽  
Rare Earths ◽  
Periodic System ◽  
Periodic Table ◽  
Atomic Weight ◽  
The Other ◽  
Niels Bohr ◽  
General Consensus ◽  
The University ◽  
Missing Element

The story concerning the discovery and isolation of element 72 bears all the characteristics of controversy and nationalistic overtones that seems to characterize many of our seven elements. On one hand, it seems odd that there should be so much controversy associated with these elements given that Moseley’s method had apparently provided an unequivocal means through which elements could be identified as well as a way of knowing just how many elements remained to be discovered. On the other hand, perhaps it was precisely because the problem of the missing elements became so clearly focused on a few elements, with known atomic numbers, that the stakes became higher than they would have been if the number of elements remaining to be discovered had been uncertain, as they were in pre-Moseley times. Element 72 (fig. 4.1) was clearly anticipated, although not as such, even in Mendeleev’s earliest table of 1869. As fig. 4.2 shows, Mendeleev considered that an as yet undiscovered element with an atomic weight of 180 should be a homologue of zirconium (The modern accepted value is 178.50). This fact may not seem very significant and yet we will see, as the story of this chapter unfolds, that it amounts to Mendeleev predicting that this element would be a transition metal rather than a rare earth. But Mendeleev was not really in a position to make such a statement since the nature and number of rare earth elements was unknown in his day. Indeed, the problem of the rare earths was one of the most acute challenges to his periodic system and one that he personally never resolved. Sometime later, Julius Thomsen, a chemistry professor at the University of Copenhagen and incidentally the chemistry instructor to the physicist Niels Bohr, published a periodic table in which he too included a missing element that was a homologue of zirconium (fi g. 4.3). Suffice it to say that there was a general consensus among chemists that on the basis of the periodic table there should exist an element before tantalum that would be a homologue of zirconium.

scholarly journals Lateritization process of peridotites in Siruka, Choiseul, Solomon Islands

2015 ◽  
Vol 3 (2) ◽  
Author(s):  
Christopher V. Sagapoa ◽  
Akira Imai ◽  
Takeyuki Ogata ◽  
Kotaro Yonezu ◽  
Koichiro Watanabe
Keyword(s):  
Solomon Islands ◽  
The Other ◽  
Nickel Laterite ◽  
Serpentinized Peridotite ◽  
Other Hand ◽  
Low Concentrations ◽  
Residual Elements ◽  
Weathering Crusts ◽  
Iron Chromium ◽  
Cobalt And Nickel

The lateritic weathering crusts exposed in Siruka, Choiseul Islands, Solomon Islands, were developed on the expense of serpentinized peridotite underlain by Siruka schists and Voza lavas with a subhorizontal contact. The lateritic profiles consist of three generalized zones: bedrock, saprolitic zone (weathered and decomposed zone) and the limonitic zones. The profiles demonstrate variations in depths and continuity but illustrate mineralogy and geochemical affinity down profile and are analogous to saprolitic nickel laterite deposits. Silica and magnesia in the bed rock and the saprolitic zones have been removed and only the residual elements (iron, chromium, aluminium, manganese, cobalt and nickel) remain in the limonitic zone. These elements are relatively concentrated as a result of the removal of the soluble elements. Nickel is associated with silica and magnesia, as lizardite ormixed gels (garnierite nickel ore) at the weathering fronts. On the other hand, nickel, with generally low concentrations (

II.—Pecus and Pecunia

1888 ◽  
Vol 9 ◽  
pp. 26-30
Author(s):  
William Ridgeway
Keyword(s):  
The Other ◽  
Present Writer ◽  
Asia Minor ◽  
Weight System ◽  
Natural Unit ◽  
Italian Peninsula ◽  
Other Hand ◽  
Historical Times ◽  
Gold Coins

In a late number of the Journal of Hellenic Studies the present writer endeavoured to show, (1) that in the Homeric poems the gold talanton simply represented the value of the ox or cow, a relation which remained at Delos down into historical times, and (2) that the actual value of both units was a gold daric, or gold Attic stater (two drachms) of 130–135 grains Troy; in fact the standard on which all the gold coins, and a large proportion of the silver coins of Greek Proper were struck; and at the same time the basis of the standards of Asia Minor, Syria, and probably of Egypt. I then confined myself to the countries immediately bordering on the Aegean, and did not attempt to deal with the weight system of the Italian Peninsula. I propose in the present paper to examine the Roman system, and to seek for it, as I have tried for the others, a natural unit, by which I mean a metallic unit based on some older unit of barter.Dr. Hultsch remarks (Metrologie, p. 151) that whilst the weight unit of the Roman pound is the most accurately known of all ancient standards, its origin on the other hand is the most obscure. The Roman libra weighed 327·45 grammes. Though it was adjusted at a later period to the Attic system, it plainly dated from a period long before Rome had come into contact with the culture of Athens.

2. A quick overview of the modern periodic table

2019 ◽  
pp. 10-29
Author(s):  
Eric R. Scerri
Keyword(s):  
Quantum Mechanics ◽  
Atomic Number ◽  
Periodic Table ◽  
Chemical Elements ◽  
Atomic Weight ◽  
Equivalent Weight ◽  
Periodic Law ◽  
The Way

‘A quick overview of the modern periodic table’ explains the arrangement of elements in the periodic table, and introduces the concept of periodic law. Elements were originally ordered by their equivalent weight, but this was superseded by atomic weight, and then atomic number. There are many versions of the periodic table, but all obey periodic law, which states that after certain regular, but varying intervals, the chemical elements show an approximate repetition in their properties. Developments in physics, especially quantum mechanics and relativity, have changed the way we think about elements and periodicity. The number of known elements has increased to 118 as the result of the synthesis of artificial elements.

I.—Shul and Shal In The Chaucer Manuscripts

PMLA ◽  
1911 ◽  
Vol 26 (1) ◽  
pp. 6-30
Author(s):  
Carleton Brown
Keyword(s):  
The Other ◽  
Present Writer ◽  
Other Hand ◽  
The Relationship

Before we may hope to solve some of the problems which confront the student of Chaucer we must gain a clearer understanding of the relationship in which the extant mss. stand to the text written by the poet's own hand. In the hope of throwing some light upon this relationship it occurred to the present writer to apply to all the Chaucer mss. thus far printed a very obvious grammatical test by noting their usage in the case of the plural present indicative of the verb shullen. The use of this test first suggested itself as a result of my observation that in these forms there is a curious variation among different mss., and even in the same ms. in different portions of Chaucer's text. These reversals of usage in the same ms. are best illustrated in Camb. Gg. 4, 27, for this manuscript contains not only the Cant. Tales, but also Troilus, the Parl, of Foules, and the Legend of G. W. In the Parl, of F. one finds the plural of the present indicative written schul eight times and schal only once; in Troilus, on the other hand, there are no less than forty-one schal's as against eight schul's. Much the same ratio is found in the Legend, which has eleven schal's and only two schul's. Moreover, among the several tales of the Canterbury collection this manuscript shows marked difference of usage, swinging abruptly from six to two in favor of schal in the Man of Law's Tale to nine to one in favor of schul in the Wife of Bath's Tale, which immediately follows. Similar examples of reversal of usage in these forms might be cited in nearly all the printed mss. Such alternations between schal and schul on the part of the same scribe are evidently due to variations in the mss. from which he was copying. In other words, the responsibility for this variation in usage does not rest upon the scribes of the extant mss.,—though they may have added to the confusion already existing. It is clear, then, that this confusion between shul and shal must proceed, either from scribes intermediate between Chaucer and the extant copies or—from Chaucer himself.

Circumvention of the Law in Talmudic Literature

1982 ◽  
Vol 17 (2) ◽  
pp. 151-168
Author(s):  
Shmuel Shilo
Keyword(s):  
The Other ◽  
Present Writer ◽  
Clear Picture ◽  
Other Hand ◽  
Cursory Examination ◽  
The Law ◽  
Systematic Explanation ◽  
The Way

A cursory examination of the Talmudic sources relating to circumvention of the law is sufficient to show that two approaches exist, one affirmative and permitting it and one negative and forbidding it. “A person may contrive to bring his produce in whilst still in its chaff so that his animal may eat it without its becoming liable to tithe”. “A person may contrivingly mix his grain with stubble in order to exempt it from tithe”. There are many similar dicta. On the other hand, for example, in theTosefta Taharotwe find in a number of matters “provided he does not act contrivedly for if he does they are impure”.Can these sources be reconciled to give a more or less clear picture of the way in which the rabbis approached the question of circumvention of the law? Rosh (R. Asher b. Yehiel, Germany, Spain c. 1250–1327), for instance, conscious of the attendant difficulties, observed with regard to rules of rabbinical provenance: “Not every circumvention… is the same. Some are generally permitted… Others are permitted only to students of the law… Still others are entirely forbidden and the rabbis treat them more rigorously than deliberate acts… And then there are those over which opinion is divided”. Rosh thus sets out the problem but suggests no solution. In the view of the present writer the sources lend themselves to systematic explanation which rebuts the remark of Rashba (R. Solomon Ibn Abraham Adret, Spain c. 1235–1310) that no two cases of circumvention are alike.

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