Lexicology as a branch of linguistics. Subject matter. Links with other branches. Problems.

In Figure 4.2c for natural gases without a liquid hydrocarbon (or when liquid

hydrocarbons exist below 273 K), the lower portion of the pressure–temperature

phase diagram is very similar to that shown in Figure 4.2a. Two changes are

(1) the LW–H–V line would be for a fixed composition mixture of hydrocarbons

rather than for pure methane (predictions methods for mixtures are given in

Section 4.2 and in Chapter 5) and (2) quadruple point Q1 would be at the

intersection of the LW–H–V line and 273 K, at a pressure lower than that for

methane. The other three-phase lines of Figure 4.2a (for I–LW–H and I–H–V)

have almost the same slope at Q1. Otherwise, the same points in Section 4.1.1

apply.

However, for the case in which natural gases contain heavier components, the

upper portion of the diagram is more like that shown in Figure 4.2b. A straight

line labeled LW–H–V represents the hydrate formation region equivalent to the

region between quadruple point Q1 (I–LW–H–V) and the upper quadruple point

Q2 (LW–H–V–LHC) in Figure 4.2b. One significant change in Figure 4.2c is that

quadruple point Q2 becomes a line, as indicated in the next paragraph.

When a liquid hydrocarbon mixture is present, the LW–V–LHC line in

Figure 4.2b broadens to become an area, such as that labeled CFK in Figure 4.2c.

This area is caused by the fact that a single hydrocarbon is no longer present, so

a combination of hydrocarbon (and water) vapor pressures creates a broader phase

equilibrium envelope. Consequently, the upper quadruple point (Q2) evolves into

a line (KC) for the multicomponent hydrocarbon system.

Line KC may not be straight in the four-phase region but is drawn that way

for illustration. The location of the lower point K is determined by the intersection

point of the phase envelope ECFKL with the LW–H–V line, determined

by the methods of Section 4.2 or Chapter 5. To determine the upper point C,

first a vapor–liquid equilibrium calculation is performed, assuming the liquid

phase (exiting the envelope at point C) equals the vapor composition at point K.

That liquid is used to calculate a vapor composition which is used in a vapor–

liquid water–hydrate calculation to determine the upper intersection with the phase

envelope ECFKL.Amore thorough treatment of the calculation of multicomponent

equilibrium with a condensed hydrocarbon phase is given in Sections 4.3.2.

Гидраты смесей углеводородных и неуглеводородных компонентов.

Гидраты природных углеводородных газов.

Lexicology as a branch of linguistics. Subject matter. Links with other branches. Problems.

Lexicology is a science about words. It studies the vocabulary of the language which consists of words and word combinations. The subject matter of lexicology is separate words, their morphological and semantic structure, and the vocabulary of the language, which includes words, word combinations, their origin, developement and current use.

Lexicology has lots of connections with other branches which also have word as a central unit. If lexicology studies the meaning of the word, Grammar studies grammatical problems. Both study roots, morphemes, affixes. But, unlike grammar, lexicological function is to name objects.Word is the smallest part of the sentence, and the sentence in its turn is the smallest communicative unit. Also it lexicology has connections with Phoenetics. If we change the stress, we change the meaning of the word and even part of the speech: rEcord – recOrd, cOment – comEnt; blackboard – black board, blackbird – black bird. Also it has some links with Stylistics. One of the problems of lexicology is stylistic characteristics. Stylistics studies different stylistic styles. The reflection of the style is in the text. E.g. bookish style we often can find in classical fiction or textbooks; collocations – in speech. And the last connection is with Social Lingusitics (Cultural Studies): language is a part of the culture, it’s a reflection of the mentality of people. There are some specific word combinations and associations in every language. E.g. professions: kindness is associated with social workers.

There are some special Problems in lexicoogy: word formation and word combination. Phraseology (science about phrases) studies it. When we start studying a new language, we try to know all the words and their meaning. And especially collocations that are unique in every language: wash hair – мыть голову, wash head – “намылить шею“. Specific feature of English is the Polysemy and Homonymy. Why? 1) It has a great number of mono-syllabic words; 2) Its analytical character. Word order is also very important. Lexicology studies words. A word has a meaning and a form. The approaches to find the meaning of the word are the following: 1) Syntagmatic – surrounding, neighbouring words help to deduce the meaning; 2) Paradigmatic – with the help of synonyms and antonyms. Word formation: 1) Compounding (Composition) – joining of several stems; 2) Convertion – one part of speech into another; 3) Affixation. One more problem – Stylistic characteristics.

2.General lexicology studies general rules of lexicology, irrespectively of other more specific problems. Special lexicology studies one specific language, description of its vocabulary, vocabulary units, the main units of the language. But every special lexiclology is based on principles of general lexicology, a general theory of vocabulary.

Historical lexicology studies the development of the words (vocabulary) – Diachronic approach. Modern lexicology (descriptive) studies the words and their development at the given stage – Synchronic approach. Dia – through, syn – together, chronos – tome. Contrastive (comparative) lexicology compares mother tongue with other languages.