scholarly journals Failure Analysis of Tube Radiant Heater Hot Oil in Refinery Industry

2019 ◽  
Vol 269 ◽  
pp. 03013
Author(s):  
Moch Ardi Dimastiar ◽  
Ahmad Taufik ◽  
Anne Zulfia Syahrial
Keyword(s):  
Chemical Analysis ◽  
Crevice Corrosion ◽  
Visual Observation ◽  
The Other ◽  
Radiant Tube ◽  
Metallographic Examination ◽  
Dimensional Measurement ◽  
Depth Analysis ◽  
Radiant Heater ◽  
External Corrosion

Heater, known as a furnace or fired heater is used to heat the oil which flows through tubes around a flame. When the tubes are failed, the fired heater reliability is affected. This paper investigates the probable cause/ causes of the radiant tube failure in the fired heater. In that context, depth analysis is conducted as part of the investigative studies, involve visual observation and dimensional measurement, metallographic examination, and chemical analysis. Finally, it has been concluded that the tube radiant has mainly failed due to crevice corrosion. In the other side, spherodization and external corrosion are also found as other failure contributors.

An Introduction to Roman Retailing

2018 ◽  
Author(s):  
Steven J. R. Ellis
Keyword(s):  
The Other ◽  
Methodological Framework ◽  
Roman World ◽  
Depth Analysis ◽  
Food And Drink ◽  
The One ◽  
Value Of It

This chapter introduces the topic of retailing in the Roman world and outlines some of the important developments in its study. It establishes why the focus of the book zooms in from retailing in general to the retailing of food and drink in particular; thus from shops to bars. Another aim is to demonstrate the scope of the study, which is an in-depth analysis of specific shops and bars at Pompeii on the one hand, and on the other a broader survey of the retail landscapes of cities throughout the Roman world. Essentially this chapter provides the theoretical and methodological framework for the book, while also arguing for the value of it in the first place.

Micro- and Nano-instrument Power

2006 ◽  
Vol 973 ◽  
Author(s):  
Vassili Karanassios
Keyword(s):  
Signal Processing ◽  
Chemical Analysis ◽  
Data Acquisition ◽  
Cancer Diagnosis ◽  
Paradigm Shift ◽  
The Other ◽  
Paradigm Shifts ◽  
Comparable Performance ◽  
Wireless Interface ◽  
Capsule Size

ABSTRACTFor the last several years, we have been developing and characterizing “mobile” micro- and nano-instruments for use on-site (e.g., in the field). Although such portable, battery-operated instruments are much smaller that their laboratory-scale counterparts, sometimes they provide comparable performance and they often offer improved capabilities. As such, they are expected to cause a paradigm shift in classical chemical analysis by allowing practioners to “bring the lab (or part of it) to the sample”. Two classes of examples will be used as the means with which to illustrate the power of micro- and nano-instruments. One class involves a “patient” as the sample and an ingestible capsule-size spectrometer used for cancer diagnosis of the gastro intestinal tack as (part of) “the lab”. The other involves the “environment” as the sample and a portable, battery-operated, miniaturized instrument that utilizes a PalmPilot™ with a wireless interface for data acquisition and signal processing as (part of) “the lab”. To discuss how to electrically power such miniaturized instruments, mobile energy issues will be addressed. Particular emphasis will be paid to current or anticipated future applications and to the paradigm shifts that may prove essential in powering the next generation of miniaturized instruments.

V.—Manganese in the Sea

1876 ◽  
Vol 1 (2) ◽  
pp. 50-53 ◽  
Author(s):  
A. H. Church
Keyword(s):  
Chemical Analysis ◽  
Deep Sea ◽  
The Other ◽  
Manganese Nodules ◽  
Red Clay ◽  
Chemical Examination ◽  
Sea Bottom ◽  
Ample Supply

To the geologist, the mineralogist and the chemist, two of the observations made during the voyage of the Challenger are of especial interest. One of these observations is the occurrence over vast areas of the deep sea bottom of a peculiar red clay, containing silica, peroxide of iron, and alumina. The other discovery to which I refer has been described by Sir Wyville Thomson as the occurrence throughout this red clay of nodules of “nearly pure peroxide of manganese.” To these nodules, as well us to the red clay, an organic origin has been assigned. But the immediate source of so much manganese is hard to find, for this element is by no means an abundant constituent of animal or vegetable organisms. The difficulty is, however, somewhat lessened when the manganese nodules are submitted to a more minute chemical examination. From two correspondents I have received an ample supply of these curious concretions, accompanied by a suggestion that they should be submitted to chemical analysis.

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

An Encounter with the Other: A Thematic Analysis of Accounts of DMT Experiences from a Naturalistic Field Study

2021 ◽  
Author(s):  
Pascal Michael ◽  
David Luke ◽  
Oliver Robinson
Keyword(s):  
Field Study ◽  
Thematic Analysis ◽  
Conscious Experience ◽  
The Other ◽  
Structured Interviews ◽  
Depth Analysis ◽  
Death Experience ◽  
Extraordinary Experiences ◽  
Alien Abduction ◽  
Increasing Trends

Introduction: N, N-Dimethyltryptamine (DMT) is an endogenous serotonergic psychedelic capable of producing radical shifts in conscious experience. Increasing trends in its use, as well as new trials administering DMT to patients, indicate the growing importance of a thorough elucidation of the phenomenology the drug may occasion. This is particularly in light of the hyper-real, otherworldly, and often ontologically challenging yet potentially transformative, nature of the experience, not least encounters with apparently non-self social agents. Laboratory studies have been limited by clinical setting and lacking qualitative analyses, while online surveys’ limitations lie in retrospective design, recreational use, and both of which not guaranteeing ‘breakthrough’ experiences. Methods: We report on the first naturalistic field study of DMT use including its qualitative analysis. Screened, healthy, anonymised and experienced DMT users (40-75mg inhaled) were observed during their non-clinical use of the drug at home. Semi-structured interviews using the micro-phenomenological technique were employed immediately after their experience. This paper reports on the thematic analysis of one major domain of the breakthrough experiences elicited; the ‘other’. Thirty-six post-DMT experience interviews with mostly Caucasian (83%) males (8 female) of average 37 years were predominantly inductively coded. Results: Invariably, profound and highly intense experiences occurred. The main overarching category comprised the encounter with other ‘beings’ (94% of reports), with further subordinate themes including the entities’ role, appearance, demeanour, communication and interaction; while the other over-arching category comprised experiences of emerging into other ‘worlds’ (100% of reports), in turn consisting of the scene, the content and quality of the immersive spaces. Discussion: The present study provides a systematic and in-depth analysis of the features of the otherworldly encounter within the breakthrough DMT experience, as well as elaborating on the resonances with both previous DMT studies and other types of extraordinary experiences which also entail entity encounters. These include the alien abduction, folkloric, shamanic and near-death experience. Putative neural mechanisms of these features of the DMT experience and its promise as a psychotherapeutic agent are discussed in light of such findings.

Protogeometric Vases from Amorgos in the Museum of the British School

1989 ◽  
Vol 84 ◽  
pp. 177-185
Author(s):  
R.W.V. Catling ◽  
R.E. Jones
Keyword(s):  
Chemical Analysis ◽  
Early History ◽  
The Other ◽  
The South ◽  
South West ◽  
British School ◽  
History Of ◽  
First Time

Two vases, a cup and an oinochoe, from Arkesine in south-west Amorgos are published for the first time. It is argued that both are probably Middle Protogeometric, one an import from Euboia, the other from the south-east Aegean; chemical analysis supports both attributions. Their implications for the early history of Amorgos are discussed.

scholarly journals A Chemical Marker Proposal for the Lantana genus: Composition of the Essential Oils from the Leaves of Lantana radula and L. canescens

2010 ◽  
Vol 5 (4) ◽  
pp. 1934578X1000500
Author(s):  
José G. Sena Filho ◽  
Haroudo S. Xavier ◽  
José M. Barbosa Filho ◽  
Jennifer M. Duringer
Keyword(s):  
Quality Control ◽  
Chemical Analysis ◽  
Essential Oil ◽  
Essential Oils ◽  
The Other ◽  
Chemical Markers ◽  
Chemical Marker ◽  
High Concentration ◽  
Minor Compounds ◽  
Prior Analysis

Essential oil extracts from the leaves of two Lantana species ( L. radula Sw. and L. canescens Kunth), for which no prior analysis has been reported, were analyzed by GC-MS. This information was utilized to propose chemical markers for Lantana species so that identification between physically similar plant species can be achieved through chemical analysis. Results showed 33 constituents for L. canescens, among which β-caryophyllene (43.9%), β-cubebene (10.1%), elixene (8.6%), β-phellandrene (6.1%), α-caryophyllene (2.6%) and dehydro-aromadendrene (2.6%) were the principle components. L. radula revealed the presence of 21 compounds, the most abundant of which were β-cubebene (31.0%), β-caryophyllene (20.8%), elixene (10.0%), α-salinene (6.4%), β-phellandrene (6.1%), copaene (4.9%) cadinene (1.4%) and psi-limonene (1.4%). The high concentration of β-caryophyllene in the samples tested here and those in the literature make it a good candidate for a chemical marker for Lantana species, with β-cubebene, elixene and β-phellandrene following as minor compounds identified more sporadically in this genus. On the other hand, Lippia species, which are morphologically similar to those from the Lantana genus, would contain limonene, citral, carvacrol, β-myrcene, camphor and thymol as the main chemical markers. These chemical markers would be a powerful tool for maintaining quality control in the extraction of essential oils for use in medicinal applications, as well as in identification of plant specimens to a taxonomist.

Response of salt-loaded rats to abrupt withdrawal of salt

1963 ◽  
Vol 205 (3) ◽  
pp. 467-470 ◽  
Author(s):  
Christopher C. Fordham ◽  
Margaret Newton
Keyword(s):  
Sodium Chloride ◽  
Chemical Analysis ◽  
Skeletal Muscles ◽  
Adrenal Glands ◽  
The Other ◽  
Histologic Study ◽  
Abrupt Withdrawal ◽  
Salt Wasting ◽  
Salt Load ◽  
Aortic Blood

This study was designed to determine whether transient salt wasting follows the abrupt withdrawal of a salt load in rats. Two groups of 30 rats were pair fed an electrolyte-free diet by gavage. One group received 2.5 mm/day of sodium chloride, the other 15 mm/day; both were given 1 mm/day of potassium. After 55 days, salt was withdrawn and the animals sacrificed at several-day intervals. In part I, specimens of aortic blood and skeletal muscles were obtained for chemical analysis, and the adrenal glands were excised for histologic study. In part II, carcass values for sodium and chloride were obtained. The results were: a) There was no evidence of impaired sodium conservation following abrupt salt withdrawal. b) Histologic study of the adrenal cortices revealed flattened glomerulosa zones in the high-salt group and a striking sequential increase in width following salt withdrawal. Evidence of a renal salt-wasting defect following the abrupt removal of a sustained salt load in rats could not be demonstrated.

scholarly journals AN IDIOTYPIC CROSS-REACTION BETWEEN ALLOTYPE a3 AND ALLOTYPE a NEGATIVE RABBIT ANTIBODIES TO STREPTOCOCCAL CARBOHYDRATE

1973 ◽  
Vol 137 (3) ◽  
pp. 636-648 ◽  
Author(s):  
Thomas J. Kindt ◽  
David G. Klapper ◽  
Michael D. Waterfield
Keyword(s):  
Chemical Analysis ◽  
Cross Reaction ◽  
The Other ◽  
Light Chains ◽  
Binding Affinities ◽  
Variable Regions ◽  
Heavy Chains ◽  
Relative Binding ◽  
Group A

Two antibodies to Group C streptococcal carbohydrate isolated from an individual rabbit had similar relative binding affinities for a Group C immuno-adsorbent column. Their light chains were similar, if not identical, as were the constant regions of their heavy chains. Differences in the variable regions of the H chains of the two antibodies were detected by chemical analysis. The two antibodies had serologically identical idiotypic determinants although one antibody possessed the a3 allotype and the other had no detectable group a marker. The occurrence of such antibodies indicates the absence of obligatory associations between group a allotypes and idiotypic specificities, despite the fact that both determinants have antigenic components in the VH region of the H chain.

scholarly journals Solidification of Hypereutectic Thin Wall Ductile Cast Iron

2006 ◽  
Vol 508 ◽  
pp. 63-68 ◽  
Author(s):  
Karl Martin Pedersen ◽  
Niels Tiedje
Keyword(s):  
Nucleation And Growth ◽  
Ductile Cast Iron ◽  
The Other ◽  
Eutectic Solidification ◽  
Thin Wall ◽  
Green Sand ◽  
Metallographic Examination ◽  
Si Content ◽  
Two Stages ◽  
Two Populations

Hypereutectic ductile iron was cast in green sand moulds with four plates with thickness of 1.5, 2, 3 and 4 mm in each mould. Temperatures were measured in the 3 and 4 mm plate. The temperature curves showed that eutectic solidification was divided into two stages: primary and secondary eutectic solidification. The first stage, which was relatively short, had none or very little recalescence. Further under cooling, followed by reheating during recalescence, was necessary to initiate the second part of the eutectic solidification. Both the secondary under cooling and recalescence was larger in the 3 mm plates than in the 4 mm plates. All 1.5 mm plates contained carbides but the other plates solidified without carbides. Metallographic examination showed two populations of graphite nodules. A small group of nodules was larger than rest of the nodules. Color etching revealing the segregation of Si showed a higher Si content in the ferrite around the larger nodules compared to the ferrite around the rest of the nodules. This indicates that solidification took place along the following path: The solidification starts with nucleation and growth of primary graphite nodules. This probably starts during the filling of the mould. The primary nodules act as nuclei for austenite. As austenite easily nucleates on graphite the temperature will be the same for the 3 and 4 mm plate for the first part of the eutectic solidification. This first part of the solidification ends when concentration of carbon around austenite dendrites is too large and new nodules have to nucleate and grow. The larger under cooling for the 3 mm plates compared to the 4 mm indicates that the nucleation of new nodules is governed by kinetics even in very well inoculated melts.

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