Ignitions, extinctions and thermokinetic oscillations accompanying the oxidation of ethane in an open system (continuously stirred tank reactor)

This paper is concerned with the spontaneous oxidation of ethane and oxygen at constant pressure (1 atm) in a well stirred, continuous flow reactor (0.5 dm 3 ) over the range of vessel temperatures from 500 to 800 K and at mean residence times of 15, 30, 60 and 120 s. The reactant compositions are varied in the stages C 2 H 6 :O 2 of 8:1, 6:1, 4:1, 2:1 and 1:1, and these are chosen to match the compositions at which cool flame phenomena were observed previously by Knox & Norrish (1954) in closed unstirred vessels and by J. A. Gray (1953) in a laminar flow tube. The work is concerned principally with the thermokinetic modes that occur and the nature of transitions between them, when the vessel temperature is varied at each of the compositions and residence times. Four distinct reaction modes are found; two stationary states and two oscillatory states. The oscillatory states are associated only with the leanest compositions (C 2 H 6 :O 2 < 2:1) and fastest flow rates ( t res = 15 s). One mode is characteristic of oscillatory cool flames, the other is an oscillatory ignition. Both stationary reaction modes are found in all compositions at all residence times, one occurring at higher vessel temperatures than the other and distinguishable by its great reactivity and an accompanying stationary luminescence (CH 2 O*). In the most reactive systems (low C 2 H 6 :O 2 , low t res ) the luminescent state is entered discontinuously and although the temperature rise associated with it is not great (∆ T < 60 K), it is found to be consistent with that predicted for complete combustion of the rich ethane and oxygen in a non-adiabatic flow system. This study reveals some features of ethane oxidation that match the predictions of quite simple thermal theories for combustion and others that are a product of complex thermokinetic interactions. Quantitative tests are made possible by the assessment of heat release rates from temperature measurements by using fine-wire thermocouples and from overall stoichiometries obtained by chemical analysis.

1979 ◽  
Vol 44 (8) ◽  
pp. 2352-2365
Author(s):  
Josef Horák ◽  
Zina Sojková ◽  
František Jiráček

Control algorithm of the operating temperature is described in the reactor, which is operated at constant temperature and composition of the inlet mixture. The temperature is controlled by dosing a constant volume of the catalyst solution. The dosing frequency is determined according to the reaction temperature (deviation of the temperature from the desired value and the sign of the derivative of temperature). The control algorithm has been verified experimentally for the laboratory reactor in unstable steady state.


PMLA ◽  
1961 ◽  
Vol 76 (3) ◽  
pp. 233-239 ◽  
Author(s):  
Monroe Z. Hafter

A recent article of Leon Livingstone rightly calls attention to the importance of Pérez Galdós' assimilation of Cervantine irony as a forerunner of the concern of modern Spanish novelists about the autonomy of their characters. The unreality of rationalism, which Livingstone holds to be the germ of El amigo Manso, the imagination's capacity to create reality at the heart of Misericordia, lead to the even bolder experiments in the artistic representation of reality undertaken by Unamuno, Azorín, Valle-Inclán, and Pérez de Ayala. Anomalous for his time yet so pervasive in his work is Galdós' employment of “interior duplication” that a separate study would contribute to our fuller understanding of his art as well as to our measure of the advances in the Spanish novel of the latter half of the nineteenth century. The present essay focuses on Galdós' developing skill with internal repetitions from La Fontana de Oro (publ. 1870), through the rich complexities of the novels written between 1886–89, to their almost stylized simplicity in El abuelo (1897). Always related to Cervantine irony, the variety of verbal echoes, the mirroring of one character in another, the unconscious illumination each may offer the other, underscore the increasingly intimate wedding of form and matter with which Galdós came to unfold his narratives.


2007 ◽  
Vol 22 (2) ◽  
pp. 527-543
Author(s):  
Robert E. Rodes

But let the brother of low degree glory in his high estate: and the rich, in that he is made low.—James 1:9-10I am starting this paper after looking at the latest of a series of e-mails regarding people who cannot scrape up the security deposits required by the local gas company to turn their heat back on. They keep shivering in the corners of their bedrooms or burning their houses down with defective space heaters. The public agency that is supposed to relieve the poor refuses to pay security deposits, and the private charities that pay deposits are out of money. A bill that might improve matters has passed one House of the Legislature, and is about to die in a committee of the other House. I have a card on my desk from a former student I ran into the other day. She works in the field of utility regulation, and has promised to send me more e-mails on the subject. I also have a pile of student papers on whether a lawyer can encourage a client illegally in the country to marry her boyfriend in order not to be deported.What I am trying to do with all this material is exercise a preferential option for the poor. I am working at it in a large, comfortable chair in a large, comfortable office filled with large, comfortable books, and a large—but not so comfortable—collection of loose papers. At the end of the day, I will take some of the papers home with me to my large, comfortable, and well heated house.


2017 ◽  
Vol 9 (2) ◽  
pp. 189-207
Author(s):  
AN Ras Try Astuti ◽  
Andi Faisal

Capitalism as an economic system that is implemented by most countries in the world today, in fact it gave birth to injustice and social inequalityare increasingly out of control. Social and economic inequalities are felt both between countries (developed and developing countries) as well as insociety itself (the rich minority and the poor majority). The condition is born from the practice of departing from faulty assumptions about the man. In capitalism the individual to own property released uncontrollably, causing a social imbalance. On the other hand, Islam never given a state model that guarantees fair distribution of ownership for all members of society, ie at the time of the Prophet Muhammad established the Islamic government in Medina. In Islam, the private ownership of property was also recognized but not absolute like capitalism. Islam also recognizes the forms of joint ownership for the benefit of society and acknowledges the ownership of the state that aims to create a balance and social justice.


2021 ◽  
Vol 66 (2) ◽  
pp. 180-187
Author(s):  
І.R. Halitova ◽  
◽  
N.O. Atemkulova ◽  
G.K. Shirinbayeva ◽  
◽  
...  

The introduction of socio-pedagogical ideas into the historical and literary heritage enriches the content of training, makes it possible to enrich their practical skills through familiarity with historical experience, on the one hand, on the other hand, it enriches the inner world of social teachers as specialists, connecting the feeling and consciousness, thereby creating conditions for successful effective activities. In human society, various types of contradictions have always appeared at any time, but at the same time , methods and ways to eliminate them have been invented. Unfortunately, we have recently become interested in foreign technologies of training and education, their ideas, and have lost sight of the rich experience of the past, which includes methods and methods of social education of children and youth. The problem is that it is necessary to identify them and use them in practice. The activity of a social pedagogue , in particular, is associated with rehabilitation, socialization and other types of work among children, youth and adults. The history of social pedagogy spiritually enriches future specialists on the one hand, and on the other, helps to accumulate the experience of the past in order to use them in solving modern problems. Literary and historical materials concerning the social side of the life of the Kazakh people in this regard is important and essential.


Author(s):  
Mithilesh Kumar Jha

This chapter examines the ways through which the Maithili movement became more provocative and assertive from the beginning of the 1920s until the independence of India. It begins with not just a categorical refutation to Hindi’s claim of Maithili being its ‘dialect’, but by invoking the cultural and historical figures like Vidyapati, Govinda Das, which led to controversy between the supporters of Bengali and Maithili, it tried to galvanize and broaden its support among the Maithili speakers who were divided on the basis of caste, class, religion, region, and sects. In this period, there were many Bengali scholars who tried to project Vidyapati and Govinda Das as Bengali poets. However, the controversy was settled by the Bengali scholars themselves through their meticulous research on Vidyapati and eventually they began to support the cause of Maithili as an independent language. All these developments galvanized the support for Maithili among the Maithils who otherwise were suspicious of Maithili’s prospect in terms of either getting good education or employment. Whereas on the other hand, learning Hindi was seen not only as supporting the nationalist cause but a language that can provide better opportunities. However, Maithili elites remained ambivalent to Hindi. They could foresee its prospect but were not willing to forgo the rich literary traditions of Maithili for championing the cause of Hindi. So, while they were not inimical to Hindi, they rallied solidly behind Maithili to assert its status as an independent modern Indian language. The broadening of Maithili journalism attempts to revive its script—Mithilakshar, and formation of the Maithili Sahitya Parishad were other significant developments in this period. Gradually, these developments led to the growth of a new sense of geopolitical identity on the basis of Maithili. And Mithila-Maithil-Maithili became the key slogan of this phase of the Maithili movement.


Author(s):  
Shuichi Aoki ◽  
Hiroshi Yamazaki

Rich-lean flame burners are widely used for supplying domestic hot water and heating in Japan. These burners exhaust low NOx and CO emissions, and conventionally consist of a layered structure of lean flame with two sides of rich flame. Top-runner regulation applied for the domestic hot water generator of fuel gas, is to run to achieve the CO2 reduction two years later in Japan. Not only low NOx and CO emissions, but also higher efficiency, are required for the next generation of domestic hot water generators. Kurachi et al. confirmed experimentally that a new concept, a unique burner with air supplied from the boundary zone between the rich and lean premixed gas nozzles, produces lower NOx and CO emissions (1, 2, 3). Numerous experimental and numerical simulation studies of conventional rich-lean flame burners have been reported, and the mechanism of the complex field mixed with the rich and lean premixed gas has been clarified (4). But the characteristics of the new concept burner have only been investigated experimentally. In this study, a two-dimensional numerical simulation of the new burner was executed to clarify the mechanism of the lower NOx and CO emissions compared to the conventional burner (mesh; 25,000, chemical reaction; GRI-mech II, laminar flow). Heat input was 6.5kW (half of a full load). A conventional burner, without an air supply from the boundary zone, was also calculated to compare with the new concept burner. In a conventional burner, the reaction ratio R178 (N+NO = N2+O), which is a part of the Zeldovich mechanism, is dominant at the area downstream of the rich flame. This area is almost same as the maximum temperature area of the burned gas. The maximum temperature of the new concept burner (1,923K) is approximately 50K lower than that of the conventional burner, successfully maintaining stable combustion. Because of its lower maximum temperature, the amount of NOx emission from the new concept burner is approximately 40% of that from the conventional burner. With the air supply from the boundary zone, the concentration of CO in the flue gas also is decreased by approximately 1/3. In particular, the formation of thermal NOx in the lean flame zone is suppressed by lowering the flame temperature. The amount of CO emission from the rich flame zone is also decreased due to the promotion of complete combustion with the air supply from the boundary zone. As a result, these characteristics are in relatively good agreement with the experimental results, and the dominancy of the new concept burner is also clarified.


2013 ◽  
Vol 24 (2) ◽  
pp. 177-206 ◽  
Author(s):  
Charles Kwong

Translating culture poses fundamental problems of perception and conception far deeper than matters of linguistic expression. This essay explores some of these problems by examining Fusheng liuji (Six Records of a Floating Life), a Chinese autobiographical text that has been translated into fourteen Asian and European languages. Even without going into the details of the rendered versions, one can notice various forms of intercultural mediation and reshaping in the translated titles and added subtitles. At one end is direct, partly helpless substitution: lexically flawless “float” cannot encompass the rich matrix of philosophical connotations and artistic resonances of fu in the source culture. At the other end is active reshaping: recasting, addition and omission based on interpretive (mis)reading, including a reduction of imagistic language into abstract concept (e.g., fu becomes “fleeting”). Through examining 17 renditions of the title of Fusheng liuji, this essay offers a case study that helps to cast light on the unavoidable factor of intercultural mediation in the translation process, with special focus on the translation of philosophical and aesthetic concepts. Some forms of mediation carry more significant effects than others, and there may be differences in verbal resources and orientations in various languages worthy of notice.


Via Latgalica ◽  
2008 ◽  
pp. 37
Author(s):  
Jana Skrivļa-Čevere

Latgale is the essentially most different and most peculiar Latvian region from the perspectives of language and culture and their interaction with the cultures of other nations. Hence, this article attempts to reveal how the images of werewolves in Latgalian folklore and the means of their expression used in traditional tales differ from the rest territory of Latvia. The aim of the article is to understand the use of this relatively little studied mythical image and the features of their characters in Latgalian folklore. Previously, the author studied the features of werewolf depictions in Latvian folklore in general, and also compared it to Lithuanian folklore. The main source used in the research are five tales of werewolves, which can be found in an electronic version of Pēteris Šmits’ collected fairy tales and tales on http://valoda.ailab.lv/folklora/pasakas/saturs.htm, recorded in the dialect of the Eastern part of Latvia. Different dictionaries and encyclopedias, for example the „Interpretative Dictionary of the Latvian Language” („Latviešu valodas skaidrojošā vārdnīca”) (http://www.ailab.lv/Vardnica/), the „Dictionary of Latvian Etymology” (“Latviešu etimoloģijas vārdnīca”), the „Encyclopedia of Mythology” (“Mitoloģijas enciklopēdija”), and the „Dictionary of Foreign Words” (“Svešvārdu vārdnīca”) were used to describe the symbolical and etymological meaning of a werewolf image. The main methods used in the paper are semiotic and comparative. The semiotic method is used to explain the symbolical meaning of the werewolf image and the semantics of the word. The comparative method is used to compare the comprehension and interpretation of the werewolf image in the tales written in the Latvian and Latgalian languages, as well as to compare the structure of these tales and the use of artistic means of expression. As the result of the research, it is possible to conclude that the Latgalian tales of werewolves show features that both agree with and differ from tales of other regions. However, the means of expression in the Latgalian tales of werewolves are rather different from texts written in other regions. One of the major differences is the language which the tales are written in, as well as emotionally expressive elements in the colloquial speech of the narrators, such as the lexis of the region, dialectisms, similes, hyperbolization, and russicisms.Just like in the majority of tales from other regions, special introduction and conclusion formulas are used. The introduction formula takes the listeners into the world of fairy tales and magic, and the conclusion fromula brings them back into reality. In addition, the use of particular toponyms to gain the effect of credibility is quite common. The motive of shapeshifting wedding guests in a number of Latgalian tales is more characteristic and more common in Lithuanian folklore, but not in the folklore of other Latvian regions. Only in one of the analyzed tales a person turns into a werewolf of his own free will. What’s more, he is not a Latgalian, which subtextually implies dislike and prejudices against an alien, which is relatively typical of Latgalian folklore in general. Also, a special shapeshifting formula – a curse – is found in one tale only. Few techniques are mentioned for retrieving human form – jumping over another shot werewolf’s skin, eating a piece of bread given by a human, or cross-cutting a wolf’s skin. Among these methods the bread technique is the most common also in the tales from other Latvian regions. Also, it should be noted that the word „werewolf” is mentioned in one tale only and an expressive description of a werewolf’s appearance is missing. This probably means that this character was not very popular in Latgalian folklore, which is also proved by the small quantity of these texts. Only one tale is narrated by a man, whereas male narrators are predominant in the other regions. In addition, in some Latgalian tales there are relatively distinguished features of patriarchy, relationships between the rich and the poor, and a peculiar sense of humor for this region and its means of expression. Having conducted the research of the tales of werewolves it is quite safe to assert that the narrator’s place of residence and the region that he/she comes from has a relatively essential meaning in the choice of folkloristic motives. The social and cultural environment, the language, and mutual relations are those preconditions that form a person’s weltanschauung, perception of life and basic values. With their special mentality, emotionally colorful means of expression and an exciting, different language, the Latgalian tales are for sure distinctive from the other ones and are very important for Baltic folklore in general.


2000 ◽  
Vol 12 (05) ◽  
pp. 739-748 ◽  
Author(s):  
TERRY GANNON

In 1986 Cappelli, Itzykson and Zuber classified all modular invariant partition functions for the conformal field theories associated to the affine A1 algebra; they found they fall into an A-D-E pattern. Their proof was difficult and attempts to generalise it to the other affine algebras failed — in hindsight the reason is that their argument ignored most of the rich mathematical structure present. We give here the "modern" proof of their result; it is an order of magnitude simpler and shorter, and much of it has already been extended to all other affine algebras. We conclude with some remarks on the A-D-E pattern appearing in this and other RCFT classifications.


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