This website uses cookies to ensure you have the best experience. Learn more

Checker Essay

1244 words - 5 pages


Sulphur corrosion, is one of clearest examples of chemical problems, affecting seriously the electric industry. An interesting case of study, is the corrosion on electric transformers, where one of the most involved agents is the dibenzyl disulfide (DBDS)[1]. This is a compound, used extensively in the electric generation industry as additive in mineral oil, performing as exceptional antioxidant. However, undergoing discussion and while some authors argue that some organic compounds which compose the oil, promote the corrosive action, other ones describe the DBDS as potential corrosion agent, responsible for persistent poisoning effects over copper, and triggering continuous electric failures in power transformers [1-3]. The development of oil refining techniques, and the use of passivators, have diminished the effects, but the problem remains, reasons why are labeled as not efficient solutions. Under this context, the mechanisms involved in this chemical phenomenon are still unclear, being studied with notorious interest [4].
As is known, the corrosion process can be represented through the interaction between the sulfured species (such as DBDS), and copper surface. As has been reported in literature, to represent the surface through a small metal model, such as a cluster, is a practical advantage avoiding the excessive computational cost of modeling solid systems. In this line, many studies of interaction and adsorption using metal clusters have been described in literature [5-7]. In this context, Density Functional Theory (DFT), has shown to be a valuable tool to describe accurately a lot of molecular properties, emerged from chemical reactions up to adsorption processes, at low computational cost [8-12].
Given the above, in this work, we claim to clarify like a first approximation and through of DFT approach, the energetic and electronic effects that govern the reaction between DBDS and Cu surface, this last one, represented through Cu7 cluster and focusing especially the interaction Cu – S.

Taking in count the large number of DFT methods (functional and basis sets), a huge literature list of assessment studies has been performed, especially over finite models and clusters. Been described with balanced performance to energetic and structural properties, functionals based on generalized gradient approximation (GGA) and their hybrid version (HGGA) have been employed, altogether pseudopotentials ECP’s and all- electron basis sets, as def- and def2- have demonstrated good assessments in transition metal clusters and organic molecules [13, 14].
Additionally to referenced studies, a previous evaluation was performed where electronic parameters were compared, considering S-S and S-C bond dissociation, at different theoretical levels with experimental data (Table I). This proceeding also was applied to Cu2 and Cu7, also including vertical quantities of electron affinity, ionization potentials, chemical...

Find Another Essay On checker

Spell Checking Algorithms Essay

1318 words - 6 pages Tagging (POS), Speech Recognition (ASR), Optical Character Recognition (OCR), and Information Retrieval (IR). Spell checking is yet another significant application of computational linguistics whose research extends back to the early seventies when Ralph Gorin built the first spell checker. Today, spell check is very important and is used every day in Microsoft word and in search engines. In this paper I will discuss how spell check works. [1] 2

Plagiarism: The Big Picture Essay

1029 words - 4 pages contribution. (The Owl of Purdue, The University of Wisconsin) Another way to double check for plagiarism is to scan your work through an online plagiarism checker. This is a useful tool to use on your paper. Although these plagiarism checkers are useful, be cautious because some are not that reliable. For example, a checker called “Viper” actually makes a copy of your work and holds on to it. After a period of about 9 months, the system publishes your

Richard nixon 2

1060 words - 4 pages to the people one on one. This speech was known as the Checker Speech. This speech won Nixon the respect of the American public. Eisenhower went on to win the presidential race for the year 1952. I think that Nixon really knew what he was doing when he wrote the Checker Speech. This one area that I respect of Nixon, to go straight to the public the way he did is very commendable. While Nixon was the vice president for Eisenhower he did all the

Writing Assignment Description

646 words - 3 pages readability report on your paper to check passive writing and writing/reading grade level. Print a print screen of your readability statistics and hand in with your rough draft. Run your paper through a plagiarism checker listed on Moodle to check for questionable areas and to give you a good clue where textual citations should appear. Create a Works Cited page to list your references in MLA style format. Remember to: 1) Proofread your rough

Initiation Story

810 words - 3 pages Initiation Story "A&P", written by John Updike, is based on a moment in the life of a cashier. He was known as Sammy and he referred to his position in the grocery store as a slot checker. Sammy spent his time watching and wondering about customers. One day, while working, three girls dressed in bikinis entered the store and attracted his attention. He describes the three girls movements and watches them as they roam throughout the

Student Survival Guide

960 words - 4 pages resource guide to follow back on throughout the rest of my college journey.•Using Axia's Educational ResourcesAxia's educational resources offer program tools that are available 24 hours a day, 7 days a week to help assist students with their studies. There is an online library, student workshops, plagiarism checker, and the Center for Writing Excellence. The online library provides thousands of articles and texts for students to use as

A&P Essay

862 words - 3 pages Andrea ProhaskaOctober 9, 2014English 271Dynamic Protagonist: SammySammy, the young character in John Updike's "A & P" is truly a dynamic character. At the beginning of this short story, Sammy seems to be maintaining the status quo in his job as a checker at the local grocery store in a small New England beach town. He is content until the day that three young women walk into the grocery store in just their bathing suits, no shirts and no

Examples Of Rebellion In John Updike's A & P

721 words - 3 pages Examples of Rebellion in John Updike's "A& P" In "A & P" John Updike develops a theme of rebellion by introducing us to Sammy, a young grocery store checker with a rebellious attitude. It is through Sammy's thoughts and comments that Updike clearly shows us examples of rebellion. Starting with comments of disdain and disrespect for his customers, Updike leads up to the ultimate act of rebellion when Sammy quits his job. Updike cleverly

Nortons Lanka Garments (PVT) Ltd

2270 words - 10 pages line and sample development manager has advised to not exceeds budget and control the overhead cost specially. So there was no proper quality planning cost for the prevention poor quality risk and they more concerned thing was deliver the shipment on time. Quality Check Points  There are two check points responsible for one checker respectively output after sewing and finishing check point before packing. Then checker has to move between both

Deceiving Art

2945 words - 12 pages , episode: Is seeing believing?) Take Figure 1 for example, we see the tiles labelled A and B as different colours, but are they? In our minds we know that in Figure 1 the square is checked, therefore the coloured tile after black is white so we assume that it’s supposed to be white. If you move the loose tile from B across to A they are actually the same colour. ‘The checker-shadow illusion’ was created by a vision scientist named Edward H. Adelson of

How Technology Effects Education

645 words - 3 pages page by page just to read about an uninteresting topic, such as history. Writing reports on a type-writer was a displeasing method to write term papers; especially if that student runs out of white-out. Certain programs offer a spell-checker, thesaurus, and other helpful features, which make writing that term-paper easier. These particular programs are only a few of the educational resources available to students. Most educational boards should

Similar Essays

Picking A Prototyping Design Tool For The Car Checker Android Application

1415 words - 6 pages Introduction There is a bunch of various design tools that can based used to make medium fidelity prototypes for software user interfaces. However, there are not that many prototyping design tools that can effectively prototype a mobile application and the Car Checker android application is one of those applications. The search for a usable design tool to design a medium fidelity prototype for the car checker android application has been

Car Checker Android Application: An Evaluation Of The Final Purposed User Interface

1024 words - 5 pages Introduction The current user interface of the Car Checker Android Application was built from hours of application prototypes of the user interface, and also from hours of usability testing of the application user interface. This paper will discuss the current design and the purpose of the Car Checker Android Application, how the current application evolved from a paper prototype to a computer prototype, the design principles is the application

Haptic Interfaces: Benefits And Usage Essay

680 words - 3 pages Haptic Interfaces The usage of Haptic Interfaces on everyday devices has revolutionized the way that we will interact with computers and mobile devices for everyday usage. In this paper, I will contend that Haptic interfaces will be used in my Car Checker application, because it will be helpful with light, stimulating jolts of touch feedback in regards to buttons being pressed in the application and the vibrations that come with the

The Strength Of Password Meters Essay

887 words - 4 pages requirement is met. 2) Strength scales and labels: there would be various strength scales varying from 3 (as in Skype and PayPal which classifies as weak-fair-strong) to 6 (as in twitter which classifies as perfect-okay-could be more secure-not secure enough-obvious-too short) 3) User Information: Certain checkers consider the environment parameters relating to the user such as first name /email address etc. 4) Types • Client-side checkers: The checker