scholarly journals THE LOCATION OF THE XANTHATE GROUPS IN PARTLY SUBSTITUTED CELLULOSE XANTHATES

1957 ◽  
Vol 35 (12) ◽  
pp. 1522-1533 ◽  
Author(s):  
E. P. Swan ◽  
C. B. Purves
Keyword(s):  
Cellulose Acetate ◽  
Chlorine Dioxide ◽  
Methyl Esters ◽  
Lead Tetraacetate ◽  
Degree Of Substitution ◽  
Hydroxyl Groups ◽  
Primary Position ◽  
Standard Methods ◽  
The Third ◽  
Almost All

Cellulose sodium xanthates of degree of substitution (D.S.) 0.4 to 0.66 were methylated to xanthate S-methyl esters which were then acetylated completely, the final xanthate D.S. remaining close to the original value. Dexanthation with aqueous chlorine dioxide near pH 4.5 and −5° removed almost all of the S-methyl xanthate groups, but the loss of a few acetyl groups from, and the retention of 1 to 2% of sulphur in, the resulting cellulose acetate could not be avoided. The original xanthate groups were presumably represented in this acetate as unsubstituted hydroxyl groups, and these were located by standard methods involving tosylation–iodination, tritylation, and oxidations with lead tetraacetate. Xanthate groups appeared to occupy the third and sixth, but not the second, position in the cellulose, and 53 to 61% of the substituent was in the sixth or primary position; one sample of viscose was "ripened" before the cellulose sodium xanthate was isolated, and the value was 81%. The results were of a preliminary nature, because severe technical difficulties reduced their reliability.

scholarly journals review article on literary archeology.docx

2018 ◽  
Author(s):  
Jiexin Yi
Keyword(s):  
Comparative Literature ◽  
East Asia ◽  
Subject Matter ◽  
Japanese Literature ◽  
Review Article ◽  
The Third ◽  
Abundant Evidence ◽  
The Ancient Chinese ◽  
Almost All ◽  
Material Exchange

<p>In this review article, I have located the trajectory of development of the notion of literary archeology and the third relation of comparative literature, compared to influence and parallel ones, expounded by him in his newly published book in 2016, <i>The Third Notion of Comparative Literature: the Possibility of Literary Archeology</i>. My research shows that he has conceived this notion more than a decade ago and it’s the result of his lifetime endeavor on comparative literature in East Asia. I have employed almost all his monographs to trace the gradual formation of his ideas with two books as the focus, <i>The Third Notion of Comparative Literature: the Possibility of Literary Archeology</i> and <i>The Image of Willow: The Material Exchange and the Ancient Chinese and Japanese Literature</i>. The former aims to construct the theory of literary archeology as a renovated subject matter and the latter is composed of the case studies on willow which provide abundant evidence to illustrate his point. </p>

scholarly journals Technical note: A time-integrated sediment trap to sample diatoms for hydrological tracing

2020 ◽  
Vol 24 (10) ◽  
pp. 4709-4725
Author(s):  
Jasper Foets ◽  
Carlos E. Wetzel ◽  
Núria Martínez-Carreras ◽  
Adriaan J. Teuling ◽  
Jean-François Iffly ◽  
...  
Keyword(s):  
Water Quality Assessment ◽  
Technical Note ◽  
Sampling Effort ◽  
Terrestrial Environment ◽  
The Third ◽  
Run Off ◽  
Analysis Of Similarity ◽  
Sediment Data ◽  
Almost All ◽  
Diatom Community Composition

Abstract. Diatoms, microscopic single-celled algae, are present in almost all habitats containing water (e.g. streams, lakes, soil and rocks). In the terrestrial environment, their diversified species distributions are mainly controlled by physiographical factors and anthropic disturbances which makes them useful tracers in catchment hydrology. In their use as a tracer, diatoms are generally sampled in streams by means of an automated sampling method; as a result, many samples must be collected to cover a whole storm run-off event. As diatom analysis is labour-intensive, a trade-off has to be made between the number of sites and the number of samples per site. In an attempt to reduce this sampling effort, we explored the potential for the Phillips sampler, a time-integrated mass-flux sampler, to provide a representative sample of the diatom assemblage of a whole storm run-off event. We addressed this by comparing the diatom community composition of the Phillips sampler to the composite community collected by automatic samplers for three events. Non-metric multidimensional scaling (NMDS) showed that, based on the species composition, (1) all three events could be separated from each other, (2) the Phillips sampler was able to sample representative communities for two events and (3) significantly different communities were only collected for the third event. These observations were generally confirmed by analysis of similarity (ANOSIM), permutational multivariate analysis of variance (PERMANOVA), and the comparison of species relative abundances and community-derived indices. However, sediment data from the third event, which was sampled with automatic samplers, showed a large amount of noise; therefore, we could not verify if the Phillips sampler sampled representative communities or not. Nevertheless, we believe that this sampler could not only be applied in hydrological tracing using terrestrial diatoms, but it might also be a useful tool in water quality assessment.

The Vigor of Confederacies

2021 ◽  
pp. 78-92
Author(s):  
Robin Waterfield
Keyword(s):  
Third Century ◽  
Ancient Greek ◽  
Federal States ◽  
Central Greece ◽  
The Third ◽  
Set Up ◽  
Almost All ◽  
Familiar Form

The chief way in which the Greeks united in the third century in order to be able to offer resistance to Macedon was by forming large federal states. The two greatest of these were based in Achaea and in Aetolia, but both quickly spread well beyond these ethnic borders. “Aetolia” came to mean almost all of central Greece, and “Achaea” much of the Peloponnese. I discuss the differences between confederacies and the most familiar form of ancient Greek polity, the polis, and show how confederacies gained their strengths, before focusing on the structures set up by the Aetolians and Achaeans. By the time Antigonus came to the Macedonian throne, the Achaeans were on the rise, but the Aetolians were already a powerful threat. They had spearheaded the Greek repulsion of the Celts from central Greece, thus preserving Delphi, the most important of the Greeks’ common religious centers, and they used this as a springboard for further expansion. Antigonus treated them warily throughout his reign.

Materialism in the philosophy of mind

2018 ◽  
Author(s):  
Howard Robinson
Keyword(s):  
Philosophy Of Mind ◽  
Subjective Experience ◽  
Mental States ◽  
Main Difficulty ◽  
Ordinary Sense ◽  
Causal Dependence ◽  
Physical Relation ◽  
The Third ◽  
Almost All ◽  
The Mind

Materialism – which, for almost all purposes, is the same as physicalism – is the theory that everything that exists is material. Natural science shows that most things are intelligible in material terms, but mind presents problems in at least two ways. The first is consciousness, as found in the ‘raw feel’ of subjective experience. The second is the intentionality of thought, which is the property of being about something beyond itself; ‘aboutness’ seems not to be a physical relation in the ordinary sense. There have been three ways of approaching these problems. The hardest is eliminativism, according to which there are no ‘raw feels’, no intentionality and, in general, no mental states: the mind and all its furniture are part of an outdated science that we now see to be false. Next is reductionism, which seeks to give an account of our experience and of intentionality in terms which are acceptable to a physical science: this means, in practice, analysing the mind in terms of its role in producing behaviour. Finally, the materialist may accept the reality and irreducibility of mind, but claim that it depends on matter in such an intimate way – more intimate than mere causal dependence – that materialism is not threatened by the irreducibility of mind. The first two approaches can be called ‘hard materialism’, the third ‘soft materialism’. The problem for eliminativism is that we find it difficult to credit that any belief that we think and feel is a theoretical speculation. Reductionism’s main difficulty is that there seems to be more to consciousness than its contribution to behaviour: a robotic machine could behave as we do without thinking or feeling. The soft materialist has to explain supervenience in a way that makes the mind not epiphenomenal without falling into the problems of interactionism.

scholarly journals Molecular Systematics and Patterns of Diversification in Pyrrhura (Psittacidae), with Special Reference to the Picta-Leucotis Complex

The Auk ◽  
2006 ◽  
Vol 123 (3) ◽  
pp. 660-680 ◽  
Author(s):  
Camila C. Ribas ◽  
Leo Joseph ◽  
Cristina Y. Miyaki
Keyword(s):  
Phylogenetic Analysis ◽  
Mitochondrial Dna ◽  
Molecular Systematics ◽  
Neotropical Forests ◽  
The Third ◽  
Species Pairs ◽  
Age Variation ◽  
Mtdna Diversity ◽  
Almost All ◽  
Evolutionary Lineages

AbstractParakeets in the genus Pyrrhura occur in Amazonia and in almost all other major Neotropical forests. Their uneven distribution (with some widespread and several geographically restricted endemic taxa) and complex patterns of plum- age variation have long generated a confused taxonomy. Several taxonomically difficult polytypic species are usually recognized. Here, we present a mitochondrial DNA (mtDNA) phylogenetic analysis of Pyrrhura, with emphasis on the especially problematic picta-leucotis complex, to provide a more robust basis for interpreting the systematics and historical biogeography of the group. Our main findings are that (1) Pyrrhura can be divided into three main evolutionary lineages, one comprising P. cruentata, an Atlantic Forest endemic, the second comprising the picta-leucotis complex, and the third comprising the remaining species; (2) the traditionally recognized species P. picta and P. leucotis are not monophyletic; and (3) most of the species recognized by Joseph (2000, 2002) are diagnosable as independent evolutionary units, with the exception of the following species pairs: P. snethlageae and P. amazonum, P. leucotis and P. griseipectus, and P. roseifrons and P. peruviana. Other than P. cruentata, the two clades that constitute Pyrrhura appear to have radiated and evolved their present mtDNA diversity over short periods during the Plio-Pleistocene.Sistemática Molecular y Patrones de Diversificación en Pyrrhura (Psittacidae), con Énfasis en el Complejo Picta-Leucotis

Electrophoresis of dyed polysaccharides on cellulose acetate

1968 ◽  
Vol 46 (19) ◽  
pp. 3079-3084 ◽  
Author(s):  
W. F. Dudman ◽  
C. T. Bishop
Keyword(s):  
Free Boundary ◽  
Cellulose Acetate ◽  
Gel Filtration ◽  
Degree Of Substitution

Polysaccharides have been shown to react with Procion dyes to give colored products. The degree of substitution varies with the dye to polysaccharide ratio used in the reaction and with the structure of the polysaccharide. The dyed polysaccharides give visible bands on gel filtration and on electrophoresis on cellulose acetate strips. Separations of mixtures of colored polysaccharides by the latter method are complete within 5 min and match the results obtained with the undyed polysaccharides by free-boundary, Tiselius electrophoresis.

Monetary policy

1953 ◽  
Vol 12 (01) ◽  
pp. 1-25
Author(s):  
H. W. Haycocks
Keyword(s):  
Monetary Policy ◽  
Economic System ◽  
Private Enterprise ◽  
The Third ◽  
Proper Functioning ◽  
The Subject ◽  
Almost All

The proper functioning of a present-day economic system is dependent upon money and prices. This is particularly the case when a large part of the economy is based on private enterprise.For many years economic text-books have stated the three functions of money to be (1) a means of payment, (2) a store of value and (3) a unit of account. The third function will not be considered in this paper, although a study of the controversy that has occurred recently about the correct principles of accountancy at times when prices change substantially will convince the reader that this function is important.Whilst all three functions of money have been recognized for many years, the emphasis given to each has changed radically from time to time. Prior to 1930 almost all the emphasis was given to money as a means of payment. This led to an approach to the subject which has been called the transactions-velocity approach.

PURIFICATION OF THE GAMMA GLOBULIN CHARACTERISTIC OF CEREBROSPINAL FLUID

1962 ◽  
Vol 40 (1) ◽  
pp. 1811-1818 ◽  
Author(s):  
Catherine F. C. MacPherson
Keyword(s):  
Cerebrospinal Fluid ◽  
Gamma Globulin ◽  
Relative Concentration ◽  
The Other ◽  
The Third ◽  
Almost All ◽  
Deae Column

Experiments are described which have led to the standardization of a procedure for the purification of the γc globulin characteristic of cerebrospinal fluid (CSF). The procedure involves the stepwise elution of three chromatographic fractions from a DEAE column by TRIS–HCl buffers at pH 8.5. The composition of the fractions will vary with the relative concentration of the γc globulin in the CSF applied to the column. From an average CSF pool the first fraction, F1, eluted by 0.002 M TRIS–HCl will usually contain only the γc globulin. The second fraction F2, eluted by 0.02 M TRIS-HCl, will contain a mixture of the γc, γs, and βc globulins. The third fraction F3, eluted by 0.08 M TRIS–HCl, will contain chiefly γs globulin as well as traces of the γc and βc globulins. Most of the γc globulin from pooled CSF may then be obtained in purified form by rechromatographing the F2's from several runs. Almost all of the γc globulin applied will be found in F1. The γs and βc globulins will be eluted in the other two fractions.

Cyclic hydroxycarboxylic acids. III. Tosylation studies on Mono- and Di-hydroxycyclopentanecarboxylates and Mono- and Di-hydroxyprolines

1977 ◽  
Vol 30 (1) ◽  
pp. 131 ◽  
Author(s):  
RP Philp ◽  
AV Robertson
Keyword(s):  
Free Amino ◽  
Heterogeneous System ◽  
Methyl Esters ◽  
Hydroxyl Groups ◽  
Large Excess ◽  
Molar Ratios ◽  
Tosyl Chloride ◽  
Hydroxycarboxylic Acids ◽  
Hydroxy Proline ◽  
Cis And Trans

A large excess of reagent is needed for satisfactory ditosylation of methyl c-2,t-3- and t-2,c-3-di-hydroxycyclopentane-r-1-carboxylates using tosyl chloride-pyridine at 5° overnight. With less reagent, mixtures are produced from which one monotosyl derivative of the t-2,c- 3-series was isolated and its structure proved. By contrast, the methyl cis- and trans-2-hydroxycyclopentanecarboxylates readily tosylate with normal molar ratios of reagent. In the proline series ditosylation of 2,3-trans- 3,4-cis-3,4-dihydroxy-N-tosylproline methyl ester occurs normally in tosyl chloride-pyridine, and so does tosylation of both cis- and trans-4-hydroxy-N-tosylproline methyl esters. On the other hand tosylation of the 3-hydroxy counterparts is very slow, although acetylation of these 3-hydroxyl groups proceeds normally. The O-tosylation results are striking for the lack of pattern. A comparison is also made of O-tosylation accompanying N-tosylation of the free amino acids cis- and trans-3-hydroxy-proline, cis- and trans- 4- hydroxyproline, and the two cis-glycols of 3,4-dihydroxyproline in the heterogeneous system tosyl chloride-ether-aqueous NaOH. Significant O- tosylation occurs in some cases but not in others. This correlation permits assignment of structure to a mono-O-tosyl derivative of a 3,4- dihydroxy-N-tosylproline obtained previously by us.

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