Specimen Collection Effect in Scanning Electron Microscopy Images

1972 ◽  
Vol 30 ◽  
pp. 448-449
Author(s):  
J. Temple Black ◽  
Jose Guerrero
Keyword(s):  
Surface Morphology ◽  
Secondary Electron Emission ◽  
Secondary Electrons ◽  
Charge Effects ◽  
Material Density ◽  
Specimen Collection ◽  
The Subject ◽  
Curved Paths ◽  
Subject Material ◽  
Microscopy Images

In the SEM, contrast in the image is the result of variations in the volume secondary electron emission and backscatter emission which reaches the detector and serves to intensity modulate the signal for the CRT's. This emission is a function of the accelerating potential, material density, chemistry, crystallography, local charge effects, surface morphology and especially the angle of the incident electron beam with the particular surface site. Aside from the influence of object inclination, the surface morphology is the most important feature In producing contrast. “Specimen collection“ is the name given the shielding of the collector by adjacent parts of the specimen, producing much image contrast. This type of contrast can occur for both secondary and backscatter electrons even though the secondary electrons take curved paths to the detector-collector.Figure 1 demonstrates, in a unique and striking fashion, the specimen collection effect. The subject material here is Armco Iron, 99.85% purity, which was spark machined.

South Sea Tales

2008 ◽  
Author(s):  
Robert Louis Stevenson
Keyword(s):  
Nineteenth Century ◽  
Cross Cultural ◽  
Robert Louis Stevenson ◽  
Global Culture ◽  
Cultural Encounters ◽  
Post Colonial ◽  
The Pacific ◽  
South Sea ◽  
The Subject ◽  
Subject Material

The literary world was shocked when in 1889, at the height of his career, Robert Louis Stevenson announced his intention to settle permanently on the Pacific island of Samoa. His readers were equally shocked when he began to use the subject material offered by his new environment, not to promote a romance of empire, but to produce some of the most ironic and critical treatments of imperialism in nineteenth-century fiction. In these stories, as in his work generally, Stevenson shows himself to be a virtuoso of narrative styles: his Pacific fiction includes the domestic realism of ‘The Beach at Falesé, the folktale plots of ‘The Bottle Imp’ and ‘The Isle of Voices’, and the modernist blending of naturalism and symbolism in The Ebb-Tide. But beyond their generic diversity the stories are linked by their concern with representing the multiracial society of which their author had become a member. In this collection - the first to bring together all his shorter Pacific fiction in one volume - Stevenson emerges as a witness both to the cross- cultural encounters of nineteenth-century imperialism and to the creation of the global culture which characterizes the post-colonial world.

scholarly journals Dentoskeletal Effects and “Effective” Temporomandibular Joint, Maxilla and Chin Changes in Good and Bad Responders to van Beek Activator Treatment

2007 ◽  
Vol 77 (1) ◽  
pp. 64-72 ◽  
Author(s):  
Sabine Ruf ◽  
Margareta Bendeus ◽  
Hans Pancherz ◽  
Urban Hägg
Keyword(s):  
Temporomandibular Joint ◽  
Class Ii ◽  
Good Responder ◽  
Skeletal Changes ◽  
Maxillary Molars ◽  
Division 1 ◽  
The Subject ◽  
Subject Material ◽  
Lateral Head ◽  
Lower Incisors

Abstract Objective: To assess possible differences in dentoskeletal effects and “effective” temporomandibular joint, maxilla, and chin changes between good and bad responders to van Beek activator treatment. Materials and Methods: The subject material consisted of 20 consecutive normodivergent male Class II division 1 patients treated with a van Beek activator. Because of insufficient cooperation, four patients were excluded. Lateral head films were taken 6 months before treatment, at start of treatment, and after 12 months of treatment. The patients were placed into a good responder group (successful, n = 8) and a bad responder group (unsuccessful, n = 8). An overjet reduction ≥4 mm was considered successful. Results: During the van Beek treatment period, the good responders showed a significantly larger improvement in overjet and molar relationship than did the bad responders. The good responders exhibited a significant posterior development of condylion, less anterior mandibular autorotation, retrusion of upper incisors, protrusion of lower incisors, distalization of maxillary molars, and a mesial movement of mandibular molars. No significant dental movements were seen in the bad responders. Conclusions: Although van Beek activator treatment affected the direction of condylar growth, as well as the direction of maxilla and chin changes, it can be concluded that skeletal changes did not contribute to the Class II correction. Instead, overjet reduction during van Beek activator treatment was found to be due to a favorable dental reaction.

MAXIMUM SECONDARY ELECTRON YIELDS FROM SEMICONDUCTORS AND INSULATORS

2016 ◽  
Vol 24 (04) ◽  
pp. 1750045 ◽  
Author(s):  
A. G. XIE ◽  
Z. H. LIU ◽  
Y. Q. XIA ◽  
M. M. ZHU
Keyword(s):  
Electron Emission ◽  
Secondary Electron ◽  
Maximum Yield ◽  
Secondary Electron Emission ◽  
High Energy ◽  
Secondary Electrons ◽  
Backscattered Electrons ◽  
Universal Formula ◽  
Yield Formula ◽  
Primary Electrons

Based on the processes and characteristics of secondary electron emission and the formula for the yield due to primary electrons hitting on semiconductors and insulators, the universal formula for maximum yield [Formula: see text] due to primary electrons hitting on semiconductors and insulators was deduced, where [Formula: see text] is the maximum ratio of the number of secondary electrons produced by primary electrons to the number of primary electrons. On the basis of the formulae for primary range in different energy ranges of [Formula: see text], characteristics of secondary electron emission and the deduced universal formula for [Formula: see text], the formulae for [Formula: see text] in different energy ranges of [Formula: see text] were deduced, where [Formula: see text] is the primary incident energy at which secondary electron yields from semiconductors and insulators, [Formula: see text], are maximized to maximum secondary electron yields from semiconductors and insulators, [Formula: see text]; and [Formula: see text] is the maximum ratio of the number of total secondary electrons produced by primary electrons and backscattered electrons to the number of primary electrons. According to the deduced formulae for [Formula: see text], the relationship among [Formula: see text], [Formula: see text] and high-energy back-scattering coefficient [Formula: see text], the formulae for parameters of [Formula: see text] and the experimental data as well as the formulae for [Formula: see text] in different energy ranges of [Formula: see text] as a function of [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] were deduced, where [Formula: see text] and [Formula: see text] are the original electron affinity and the width of forbidden band, respectively. The scattering of [Formula: see text] was analyzed, and calculated [Formula: see text] values were compared with the values measured experimentally. It was concluded that the deduced formulae for [Formula: see text] were found to be universal for [Formula: see text].

scholarly journals Fundamentos del método científico

2017 ◽  
Vol 1 (1) ◽  
Author(s):  
M. H Badii ◽  
A. R. Pazhakh ◽  
José Luis Abreu Quintero ◽  
R Foroughbakhch
Keyword(s):  
Data Collection ◽  
Research Methodology ◽  
Literature Search ◽  
Ethical Issues ◽  
Scientific Work ◽  
Scientific Methodology ◽  
The Subject ◽  
Basic Concepts ◽  
Points Of View ◽  
Subject Material

Palabras claves: Ciencia, ECOEE, investigación, métodosResumen. El objetivo de esta obra no radica en realizar una búsqueda exhaustiva de la literatura en el tema, sino, sentar las bases del método científico, notando los aspectos filosóficos e éticos de la ciencia. Se presentan los conceptos y definiciones fundamentales relacionados con la metodología de la investigación científica. Se maneja el concepto de la toma de los datos válidos como un requisito básico en cualquier trabajo científico. Se pone a disposición del lector un modelo denominado el ECOEE que es una herramienta poderosa para establecer puntos de comparación e discusión entre los resultados de diferentes trabajos científicos. Finalmente, ofrece unas sugerencias de que hacer o no hacer en cuanto a realizar un trabajo de investigación.Key words: ECOEE, methods, research, Science Abstract.The aim of this paper is not to conduct a thorough literature search on the subject material, but to stress the fundamentals of the scientific methodology along with the philosophical and ethical issues thereof. The basic concepts and definitions in relation to research methodology are presented. The concept of data collection as a basic requisite in any scientific work is discussed. The ECOEE model as a strong tool in establishing different points of view and comparison among the results of different scientific works are laid out. Finally, some tips and suggestions are given as what to do or to avoid in conducting scientific research.

scholarly journals RUDRA PARPATI: AN AYURVEDIC HERBO – MINERAL DRUG REVIEW

2021 ◽  
Vol 9 (8) ◽  
pp. 1819-1823
Author(s):  
Priyanka. B. Patil ◽  
Usha M ◽  
Ravi R Chavan
Keyword(s):  
Mode Of Action ◽  
Medical Literature ◽  
Review Article ◽  
The Internet ◽  
Pharmacological Properties ◽  
Review Articles ◽  
Therapeutic Uses ◽  
The Subject ◽  
Subject Material ◽  
Drug Review

The main objective of this review article is to discuss the therapeutic uses of Rudra Parpati and to discuss the different pharmacological properties and therapeutic uses of isolated constituent drugs of Rudra Parpati. The authentic subject material has been reviewed from Ayurveda and modern medical literature. Different research and review articles were searched in different journals. The subject material has also been searched on the internet. This review is mainly focused on different aspects of herbo mineral Ayurvedic formulation Rudra Parpati. Parpati rasayana is one among Chaturvidha Rasayana Kalpa which is very effective and can be prepared with less effort. In Ayurveda Rudra Parpati is mentioned in the management of Kasa/cough. Though it is popular as only Parpati used in Kharapaka form & having an indication other than Grahani but still an unexplored treasure with unique therapeutic utility. Hence an attempt has been made to address the therapeutic uses of Rudra Parpati and the probable mode of action of its constituent drugs. Keywords: Rudraparpati, Vataja Kasa.

scholarly journals Material Affinities: ‘Doing’ Family through the Practices of Passing On

Sociology ◽  
2018 ◽  
Vol 53 (1) ◽  
pp. 174-191 ◽  
Author(s):  
Helen Holmes
Keyword(s):  
Kinship Networks ◽  
Everyday Objects ◽  
Family Narratives ◽  
The Subject ◽  
One To One ◽  
Subject Material ◽  
Central Characters

This article explores how mundane objects are passed on through kinship networks and how these practices become part of the ‘doing’ of family and kinship. Using Mason’s concept of affinities, I illuminate four strands of material affinities, each of which illustrates how passed on objects can reproduce, imagine and memorialise kin connections both biological and social, and in and through time. Crucially, I argue that it is everyday objects in use which reveal how materiality and kinship are woven together. By starting from the object rather than the subject material affinities are brought to life, illustrating how materials are inscribed with kinship both physically and imaginatively, but in turn inscribe kinship practices, operating as central characters in family narratives. The article stems from research exploring everyday contemporary thrift and involved one-to-one interviews and a Mass Observation Directive on the subject of ‘Being thrifty’.

Detection of Single Ions by Fulse Counting: Application to Ion Microprobe Mass Analyzer

1971 ◽  
Vol 15 ◽  
pp. 36-55
Author(s):  
L. A. Dietz
Keyword(s):  
Mass Spectra ◽  
Secondary Electron Emission ◽  
Target Surface ◽  
Mass Analyzer ◽  
Ion Microprobe ◽  
Ion Detection ◽  
Secondary Electrons ◽  
Electron Multiplier ◽  
Pulse Counting ◽  
Surface Conversion

The need to detect low intensity beams of resolved ions with keV energy is encountered frequently in mass spectrometry. It is most readily accomplished by using some form of pulse-counting detector in which ions are allowed to strike a target surface (conversion dynode) where each ion releases a pulse of low energy secondary electrons. The secondary electrons undergo further amplification in an electron multiplier or scintillator type of ion detector which is specially designed to detect single ions. Ion-to-electron conversion, amplification of the secondary electrons, efficiency of ion detection by pulse counting and dead-time corrections to observed random counting rates are all statistical processes which must be understood so that observed data can be corrected properly to obtain precise and accurate measurements. These processes are reviewed, along with some of the basic properties of ion-induced secondary electron emission from an amorphous Al2O3 thin film target. Ion detection in the ion microprobe is interpreted in light of these basic considerations, and several mass spectra are given for electron multiplier dynode surfaces.

Do FEMA’s, HSEEP’s, and Green’s progressively difficult emergency exercise training concepts ultimately lead to increased emergency preparedness?

2009 ◽  
Vol 7 (5) ◽  
pp. 33
Author(s):  
Marc Glasser, MS, CPP, CEM, CHS-V, MCAS
Keyword(s):  
Exercise Training ◽  
Emergency Preparedness ◽  
Academic Research ◽  
Effective Learning ◽  
Adult Learning Principles ◽  
Training Approach ◽  
The Subject ◽  
Subject Material ◽  
Learning Principles ◽  
Educational Principle

FEMA’s, HSEEP’s, and Green’s Exercise Alternates emergency exercise training approach models are built on the fundamental educational principle that progressively difficult emergency exercise training leads to the most effective learning and comprehension which ultimately increases emergency preparedness. This article addresses the merits of the “progressive” education principle in general and within the context of emergency exercise training programs. This article also briefly addresses emergency exercise planning and standardization, adult learning principles, and the theory of andragogy. This article concludes with an analysis based on a synthesis of the information reviewed, assertions and academic research results. The research material utilized was evaluated and selected based on the credibility of the source and its applicability to the subject material.

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