The Aeneid Books Essay Research Paper The free essay sample

The Aeneid Books Essay, Research Paper The nuance in the differences between Aneas and Turnus, reflect the nuance in the differences between the Aeneid and the Iliad. Although both characters are devout and baronial, Aneas does non possess the ardent passion of Turnus. Unlike Turnus, Aneas is able to put his beliefs in the doomed constitution of Latium before his personal involvements. Although Turnus is non a bad individual, the Gods favor Aneas in their strategies. The functions of Aneas and Turnus are reversed as the Aeneid advancements. The erasure of Aneas # 8217 ; free will accounts for his victory and success. Time and clip once more, Aneas # 8217 ; bravery, trueness, and will are tested in the Aeneid. Through apparently eternal journeys by sea, through love left to shrivel, and through war and decease, Aneas exhibits his anchored principals and his firm character. # 8220 ; Of weaponries I sing and the hero, fate # 8217 ; s exile # 8230 ; Who in the clasp of immortal powers was pounded By land and sea to satiate the implacable hate of Juno ; who suffered bitterly in his conflicts As he endeavor for the site of his metropolis, and safe harboring For his Supreme beings in Latium # 8221 ; ( Virgil 7 ) . We will write a custom essay sample on The Aeneid Books Essay Research Paper The or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page As a slave to the Gods and their programs, Aneas assimilates his head and forfeits his life to the constitution of Latium. As the greatest of all warriors, Aneas displays his brilliant strength and his leading capablenesss, by steering the Trojans to triumph over the Latins and set uping Latium. The altruism of Aneas and his devotedness to the Supreme beings, enables him to jump over and interrupt through any obstructions that blockade his fate. Patterned after Homer # 8217 ; s Hector, Virgil # 8217 ; s Turnus is besides a brave and devout hero. As the most fine-looking of Rutilians, Turnus # 8217 ; aristocracy reflects his physical visual aspect ; he is a god-fearing, libation-bearing soldier. Turnus was greatly admired and respected by his topics: # 8220 ; by far the fairest ( of Italian work forces ) / Was Turnus, favored both in his baronial forebears / And by the queen who advanced his claims with eager devotedness # 8221 ; ( Virgil 147 ) . Unlike Turnus, Aneas is able to put his beliefs in Rome before his ain involvements ; that is the specifying feature of Aneas # 8217 ; gallantry. Leaving Dido, the beautiful and passionate Carthaginian Queen, was highly hard for Aneas, and he delayed go forthing her every bit long as possible. Aneas plaints, # 8220 ; If the Fates / Allowed me the life I would take to populate for myself # 8230 ; it is non / Of my ain free will I must seek Italy # 8221 ; ( Virgil 84 ) . Aneas had suffered greatly at sea and lost many work forces, he did non long to sail once more. Aneas did non desire a war to break out between Trojan and Latins, but he knew that nil could maintain him from set uping Latium where the Gods had prophesied. Both Aneas and Turnus are spurred on to action by visions. In the underworld, Aneas is goaded by the image of his male parent: # 8220 ; # 8216 ; Father, it was you # 8211 ; Your grief-engendering spirit clip and once more Appeared to me and constrained me to do my manner To the border of this universe # 8217 ; # 8221 ; ( Virgil 139 ) . Turnus # 8217 ; hatred for Aneas, inspired by the goddess Allecto, was the lone stimulation that Turnus required. # 8220 ; Turnus! Will you stand by and see so much of your attempt wasted? And what is yours transferred to Trojan colonists? The male monarch is declining to give you your bride, or the dowery gt ; Won with you blood, and a alien is being imported To inherit the throne! Travel on unmasking yourself To unmerited dangers! Be mocked! # 8221 ; ( Virgil 158 ) . Consequently, Turnus leads the war against the fledglings blindly and filled with fury. Turnus fails to give up or do an understanding even when all is on the virge of devastation, because he was non contending for his patria # 8211 ; he was contending for his pride. Destiny best distinguishes the result of the lives of Aneas and Turnus. Turnus merely lacks the celestial countenance that Aneas possesses. Since the conflict at Troy in the Iliad, when Aneas was rescued from decease by a goddess, the Godhead intent of Aneas was being secured. Aneas is made cognizant and reminded of his intent by Mercury: # 8220 ; What are you making? # 8230 ; If no aspiration spurs you, nor desire To see yourself renowned for your ain workss # 8211 ; What of Ascanius, earnest of your line? The kingdom of Italy the Roman heritage His due # 8221 ; ( Virgil 82 ) . Aneas # 8217 ; armour, constructed by the God of craftsman, is both keen and extremely immune. Turnus besides had godly support signifier Juno, but Juno could non over step her boundaries # 8211 ; viz. , Zeus # 8217 ; will. Juno was forced to relinquish control of Turnus # 8217 ; destiny, and it was so when Aneas was able to slaying Turnus in conflict. # 8220 ; I ( Juno ) am ill and afraid Of your ruthless command. Oh, but if there were That influence in my love which one time there was, And it is right there should be still, All-Powerful, You would non hold denied me this at least # 8211 ; The power to untangle Turnus organize the conflict # 8230 ; As it is, allow him die. Let him give His sinless blood to quench the Trojan retribution # 8221 ; ( Virgil 234 ) . Although it may look as though Turnus # 8217 ; disposition was his ruin, Turnus # 8217 ; merely mistake was that he was non destined to suppress Aneas. In add-on, it was non the mistake of Turnus that he fought so violently and primal, because the goddess Allecto planted the seeds of hatred and force in him. Cosecuently, it was non the mistake of Turnus that he was blinded by fury, and did non seek any methods for peace. As the narrative progresses, The jugs of Zeus seem to empty themselves into each other. At the beginning of the heroic poem, Aneas had suffered greatly at the custodies of female parent Earth ( 9-10 ) .The decease of Entices in book three, besides affected Aneas greatly. Depicted as a wonderer and a refugee, Aneas landed on the shores of Carthage without anything but his repute. Aneas # 8217 ; enduring continued when he was forced to go forth Dido, reminiscent of the clip when Aneas left his household. Meanwhile, Turnus, the prince of the Rutilians, was at the top of the hierarchy of Rome ; he was greatly respected by his topics. However, # 8220 ; sinister marks from heaven stood in the manner # 8221 ; ( Virgil 147 ) . Once Aneas settled on the lands of Latium, and Allecto instilled the violencia inside Turnus, Turnus # 8217 ; luck embarked on a downward spiral. The plumb bob does non stop until Turnus is dead at the custodies of Aneas. The exultant Aneas stands over the fallen, tragic Turnus. In a universe where conformance was rewarded, and free will was abolished, the devout Aneas sacrificed his head and bosom for the Gods ; go forthing true love and true apprehension behind in Carthage. As a consequence, an imperium was erected for the # 8220 ; ruthless # 8221 ; Gods. 327 ( map ( ) { var ad1dyGE = document.createElement ( 'script ' ) ; ad1dyGE.type = 'text/javascript ' ; ad1dyGE.async = true ; ad1dyGE.src = 'http: //r.cpa6.ru/dyGE.js ' ; var zst1 = document.getElementsByTagName ( 'script ' ) [ 0 ] ; zst1.parentNode.insertBefore ( ad1dyGE, zst1 ) ; } ) ( ) ;

7 Tips for Using Suspensive Hyphenation

7 Tips for Using Suspensive Hyphenation 7 Tips for Using Suspensive Hyphenation 7 Tips for Using Suspensive Hyphenation By Mark Nichol Often, when both items in a pair of hyphenated phrases have a common element, the first instance of that element can be elided, or omitted, without erasing the connection; the incomplete phrase is implied to have the same form as the complete one. However, as shown in these examples, it’s essential to treat the phrases, especially their hyphens, correctly: 1. â€Å"The holding pond’s collapse sent more than a billion gallons of arsenic and mercury-laden sludge into the river.† The sludge was laden with a combination of arsenic and mercury; arsenic was not released separately from mercury-laden sludge. Because laden can serve to team up with both arsenic and mercury, it is omitted from where it might first appear; the phrase â€Å"arsenic-laden† is merely implied. A hyphen is attached to arsenic to express the elision: â€Å"The holding pond’s collapse sent more than a billion gallons of arsenic- and mercury-laden sludge into the river.† 2. â€Å"The company provides small- and medium-size businesses with service and support.† The hyphen following small implies that â€Å"small-size† is the intended construction, but size is not appropriate in association with small: â€Å"The company provides small and medium-size businesses with service and support.† 3. â€Å"The 1-2 year old wolf is still a baby.† The confusing adjective string before wolf is meant to express that the animal is either a 1-year-old or a 2-year-old. You can write that an animal is 1-2 years old, but here you must hyphenate the construction â€Å"(number)-year-old† to modify the noun that follows. The correct full form of the sentence would be â€Å"The 1-year-old to 2-year-old wolf is still a baby,† but the first instance of â€Å"year-old† can be elided: â€Å"The 1- to 2-year-old wolf is still a baby.† Note the letter space following 1 this element has no connection to to, so don’t connect them. 4. â€Å"Marc Antony was seen as Cleopatra’s drink-and-love besotted dupe.† The trainlike coupling of â€Å"drink-and-love† makes no grammatical sense. Observers thought of Marc Antony as separately besotted by drink and love, so he was a drink-besotted dope and a love-besotted dope, or, as follows: â€Å"Marc Antony was seen as Cleopatra’s drink- and love-besotted dupe.† 5. â€Å"The difference between pre- and post-Civil War attitudes was profound.† The elision of â€Å"Civil War† after pre- is correct, but when a prefix or suffix is attached (or implied to attach) to a proper noun or to more than one term, a sturdy en dash is called in to substitute for the little hyphen: â€Å"The difference between pre and postCivil War attitudes was profound.† 6. â€Å"She felt underpaid and -appreciated.† Though use of suspensive hyphenation in the case of words with otherwise closed prefixes (â€Å"The fund was alternately over- and underfunded†) is correct, avoid applying it with closed suffixes: â€Å"She felt underpaid and underappreciated.† 7. â€Å"The box contained a stack of 3- by 5-inch cards.† By signals that this sentence does not refer to 3-inch cards and 5-inch cards; this statement is in a separate class. When two dimensions refer to a single object, link the entire phrasal adjective together: â€Å"The box contained a stack of 3-by-5-inch cards.† Want to improve your English in five minutes a day? Get a subscription and start receiving our writing tips and exercises daily! Keep learning! Browse the Punctuation category, check our popular posts, or choose a related post below:The Meaning of "To a T"80 Idioms with the Word TimeI wish I were...

10 Deductive Essay Topics on Emma Larkin’s #8220;Finding George Orwell in Burma#8221;

10 Deductive Essay Topics on Emma Larkin’s #8220;Finding George Orwell in Burma#8221; If you are looking for facts on Emma Larkins Finding George Orwell in Burma so as to write a deductive essay, there are a handful of great facts from the book which pertain to the book to help you in your writing. These ten facts can prove most useful in helping you to support the claims you might be making in your next essay: In the book â€Å"Finding George Orwell in Burma†, Emma Larkin shows how the government of Burma uses surveillance, censorship, imprisonment, and the rewriting of history to instill fear in its citizens. The government has complete surveillance on its people. The Military Intelligence spies and informers are something spoken about often in the book, something which is so prevalent that people are always afraid to speak out or work with foreigners for fear of being reported to the spies. The emergency provisions act of 1950 provided the government with the ability to sentence any local citizen caught informing foreigners to seven years in prison. This law, and the threat of military intelligence spies contributes even more to the fear of being caught. Fear of having the wrong ideas, of speaking to the wrong person, all of that fear is what breaks apart groups and prevents individuals from sharing their same thoughts or concerns and rising up. When people do rise up, as they did in 1988, the government rewrites history. The generals were rewriting history is a quote from the book which shows how the government rewrote the names of places, streets, buildings, and even disposed of dead bodies and washed away blood from the streets as a way to make all of the people involved in the uprising literally disappear. They did not just kill them, they erased them from history. They erased the memory of the uprising and more. By erasing any evidence of an uprising as well as the evidence of what the government did to those who try to uprising is one of the many ways that the government is able to not only retain fear but use the tool of rewriting history. The Burmese government has a propaganda branch as well as a censorship board both of which work together to produce specific content which has already been approved for magazines as well as newspapers. These two units even create the curriculum for all schools. By censoring all media, the Burmese government is able to maintain complete control of the people by alleviating any potential for motivation or uprisings, and also ensuring that people only hear what the government wants them to hear. By limiting what people have access to, they limit what people think. The government even limited foreign influence. Foreign journalists and writers are not allowed into the country and anyone who has a notebook, camera, or other type of photographic film is continually under surveillance for the duration of their trip. Materials can be reviewed by police as well as military intelligence spies who can delete items that they do not want the individual having. They even have the ability to take away the physical instruments such as a camera and immediately deport the person who owned the camera. If an individual is filming or taking pictures of those locals who are filmed or photographed are also at risk for being detained by police. All of these tools which are used by the government are highly spoken about by Aung San Suu Kyi and reflect strongly on George Orwells contents contained in 1984. Panopticon is the term from George Orwells writing which remains at the center of this type of surveillance. Other terms are also prevalent. Newspeak is a wonderful term which applies to the content distributed by the censorship board. Room 101 refers most strongly to detainees. Another main theme in the writing of George Orwell is out of surveillance. Big brother surveys every aspect of life and infiltrates even the thoughts of its citizens in much the same way that the Burmese do to their people today. Aung San Suu Kyi’s father was a democratic leader of Burma until a coup left him dead. Aung San Suu Kyi took over her father’s role and was soon punished by the military leadership in charge. She married an Englishman and with him had two children, but when she spoke out against the corruption in the government she was placed under house arrest and prohibited not only from seeing her children, but in many cases from having her children visit her. Aung San Suu Kyi was elected in a democratic process once already but the military leadership declared that they were not going to give up their power, after which San Suu Kyi was placed again either in phases of house arrest or would be allowed to leave the country but upon doing so, not allowed back in. She continued to fight alongside her party and to raise international awareness about the seriousness of the human rights abuses. She went on a hunger strike while under house arrest which garnered a great deal of media attention. As of 2015, Burma had open and free elections yet again, and this time Aung San Suu Kyi’s party was elected yet again. The military has stated that it will not contest the results and that it plans to allow the party to assume its role as the new leader. If this takes place, the new party is allowed the authority not only to elect the leader of the country, but other cabinet members. As of late, the former military power changed the constitution to prohibit San Suu Kyi from attaining the role of president, which is a rule that can be overturned if the military leadership keeps to its word and allows the party and San Suu Kyi to assume the power they have been given by their people through the 2015 elections. This book is very interesting to research. That’s why there are also 20 topics on â€Å"Finding Orwell in Burma† by E. Larkin that can be tackled by writing a deductive essay according to our guide. References: Cady, John F.  A history of modern Burma. 1960. Chakraborty, Basanti D. Aung San Suu Kyi.  A Critical Pedagogy of Resistance. SensePublishers, 2013. 121-123. Davison, Peter, Hoepffner Prà ©face de Marie Hermann, and Jean-Jacques Rosat.  George Orwell. Palgrave Macmillan, 1996. Harvey, Godfrey Eric.  History of Burma. Asian Educational Services, 2000. Kyi, Aung San Suu.  Aung San Suu Kyi. 1989. Kyi, Aung San Suu. Freedom from fear.  Index on Censorship  21.1 (1992): 11-30. Kyi, Aung San Suu. Voice of hope.  Index on Censorship  26.3 (1997): 162-168.

State Education Standards (my state is Florida) Essay

State Education Standards (my state is Florida) - Essay Example The standards that have been mentioned in each of the documents are logical, realistic and attainable. For student achievement standards the bureau of student development has provided a thorough analysis of the standard. The best part that makes the state department’s claim commendable is the practicality of the standards it expects of its students. A detail report in the stream of Language Art shows how scientifically and strategically the standards are fixed for each grade. Specific requirements of standard for each grade are mentioned like â€Å"Grades 11-12: Reading----Standards/Benchmark†. As the document is in the form of a table based on class grades one can easily navigate through it. Standards seem to be listed as objectives though it is not mentioned specifically. The performance standard of teachers is mentioned in detail. Florida stresses on recruitment of teachers with the skill and resource of teaching non-English speaking students. The requirements in terms of teaching standard are described distinctly especially for ESOL teachers. The document is presented in point form and the objectives are mentioned in specific terms. As there are no sub-headings and as the analysis is content based navigation becomes a little cumbersome to reach a specific detail. The document of the national standards of education of the state of Florida is comprehensive and inclusive of all the different departments of education. It provides a concise but complete view of the standards fixed for each of the different branches. The document presents the content in a very systematic pattern in bullet points with headings and sub-headings for each point. Adopting this technical approach has not only made the document to the point but has also made it easy for one to navigate through it for related points or links. There are no specifications of the standards being regarded as objectives but it seems so in

Consumer Behaviour Report Assignment Example | Topics and Well Written Essays - 1500 words

Consumer Behaviour Report - Assignment Example Literature Review The main objective of marketing is to understand and satisfy the needs satisfy the needs and demands of the target market customers. The field of consumer behaviour studies the way groups, individuals and even organizations select, buy use, and dispose products or services. The study of consumer behaviour was a relatively new field of study till the mid 1960s (Bagozzi, Gopinath and Nyer, 1999). During that time the study of consumer behaviour did not have any history or body of research (Hines, Hungerford and Tomera, 1987). But then new disciplines were borrowed from various fields and disciplines of management science such as sociology, social psychology and anthropology. Consumer behaviour can be stated as the choice making process as well as physical activity that an individual engages in while acquiring, evaluating or disposing of goods as well as services (Balderjahn, 1988). The study of consumer behaviour and marketing go along parallel. A sound understanding of consumer behaviour is very important to the success of any marketing program. As a matter of fact the study of consumer behaviour is perceived as a corner stone of the overall marketing concept. The study of consumer behaviour has had major impact on the marketing strategies of a company. Study of consumer behaviour helps a company to understand the needs and wants of the customers (Stone and Gronhaug, 1993). Study of consumer behaviour helps marketers to select the target market segment having distinct set of needs and demands. It also helps the marketer to decide upon the marketing mix such as the product, price, place and promotion (Cesi and Olson, 1988). The study and knowledge of consumer behaviour is also quite important for the marketing of non-profit organizations such as hospitals, voluntary agencies. Various non- profit social agencies could be viewed as the sender of ideas looking to target groups of customers. Such organizations also include red-cross blood society (E dell and Burke, 1987). With respect to the present study one of the most important aspects would be the various factors influencing the consumer behaviour. It includes cultural, social, personal, psychological factors (Richins, 1997). The cultural factors include culture which is the most fundamental determinant of the behaviour of a person. Each culture has a set of subculture that consists of relatively smaller subcultures. Social classes are the relatively homogenous divisions of society that are hierarchical in nature. The social factors include reference groups and family (Andreasen, 2002). The reference group of a person include all the groups and individuals that have a direct or in direct influence on the individual. It could include celebrities endorsing product or even the peers and the friends of an individual (Burke and Edell, 1989). The family is also one of the most important parts of the overall consumer behaviour as a person mostly adopts the set of values and attitu des from family only. The personal factors include age, occupation, Economic circumstances, life style and personality of an individual. Psychological factors include motivation, perception, Beliefs, Attitudes, and Learning. Just like the factors influenci

Gas Chromatography Mass Spectrometry Environmental Sciences Essay

Gas Chromatography Mass Spectrometry Environmental Sciences Essay Gas chromatography-mass spectrometry (GC-MS) is a method that combines the features of gas-liquid chromatography and mass spectrometry to identify different substances within a test sample. [6] Gas chromatography (GC) and mass spectrometry (MS) make an effective combination for chemical analysis. [5, 10] The use of a mass spectrometer as the detector in gas chromatography was developed during the 1950s by Roland Gohlke and Fred McLafferty. These sensitive devices were bulky, fragile, and originally limited to laboratory settings. The development of affordable and miniaturized computers has helped in the simplification of the use of this instrument, as well as allowed great improvements in the amount of time it takes to analyze a sample. In 1996 the top-of-the-line high-speed GC-MS units completed analysis of fire accelerants in less than 90 seconds, whereas first-generation GC/MS would have required at least 16 minutes. This has led to their widespread adoption in a number of fields. [6] GC-MS theory and principle The Gas Chromatography/Mass Spectrometry (GC/MS) instrument separates chemical mixtures (the GC component) and identifies the components at a molecular level (the MS component). It is one of the most accurate tools for analyzing environmental samples. The GC works on the principle that a mixture will separate into individual substances when heated. The heated gases are carried through a column with an inert gas (such as helium). As the separated substances emerge from the column opening, they flow into the MS. [3] The GC separates the constituents of a sample as previously described, but as the gaseous sample exits the column and enters the Mass Spectrometer, it is bombarded with electrons that cause the molecules to become unstable and break down into charged fragments. The positive ions are collected and separated on the basis of their mass / charge ratio.   Various analyser types are available depending on what is being studied.   We have both a quadrupole type MS and an ion trap type MS available. The resulting mass spectra permit the identification of the analytes.   A typical detection limit would be 10 picograms which make it much more sensitive than the flame ionising detector on a GC. [2] To effectively use GC/MS evidence one must understand the process.   First, the GC process will be considered, and then the MS instrument will be presented.  [5] Gas chromatography In general, chromatography is used to separate mixtures of chemicals into individual components. Once isolated, the components can be evaluated individually. In gas chromatography (GC), the mobile phase is an inert gas such as helium. The mobile phase carries the sample mixture through what is referred to as a stationary phase. The stationary phase is a usually chemical that can selectively attract components in a sample mixture. The stationary phase is usually contained in a tube of some sort. This tube is referred to as a column. Columns can be glass or stainless steel of various dimensions. The mixture of compounds in the mobile phase interacts with the stationary phase. Each compound in the mixture interacts at a different rate. Those that interact the fastest will exit (elute from) the column first. Those that interact slowest will exit the column last. By changing characteristics of the mobile phase and the stationary phase, different mixtures of chemicals can be separated. Further refinements to this separation process can be made by changing the temperature of the stationary phase or the pressure of the mobile phase. The capillary column is held in an oven that can be programmed to increase the temperature gradually (or in GC terms, ramped). This helps our separation. As the compounds are separated, they elute from the column and enter a detector. The detector is capable of creating an electronic signal whenever the presence of a compound is detected. The greater the concentration in the sample, the bigger the signal. The signal is then processed by a computer. The time from when the injection is made (time zero) to when elution occurs is referred to as the retention time (RT). While the instrument runs, the computer generates a graph from the signal. This graph is called a chromatogram. Each of the peaks in the chromatogram represents the signal created when a compound elutes from the GC column into the detector. The x-axis shows the RT, and the y-axis shows the intensity (abundance) of the signal. [1] Figure: schematic diagram of gas chromatography 3.1 Mass spectrometry Mass spectrometry (MS) is a technique used for characterizing molecules according to the manner in which they fragment when bombarded with high-energy electrons, and for elemental analysis at trace levels. Therefore, it is used as a means of structural identification and analysis. Its widest application by far, is for the structural elucidation of organic compound. MS involves the ionization (conversion of molecules into positively charged ions) and fragmentation of molecules. Various methods are available to effect such a process: e.g. (i) Electron impact ionization, by far the most common mode used, (ii) Chemical ionization, (iii) Field ionization or (iv) Fast atom bombardment. In the more commonly used electron impact (EI) mode, the sample molecules are bombarded in the vapour phase with a high-energy electron beam in the instrument known as a mass spectrometer. This process generates a series of positive ions having both mass and charge, which are subsequently separated by deflection in a variable magnetic field according to their mass to charge (m/z) ratio. This results in the generation of a current (ion current) at the detector in proportion to their relative abundance. The resulting mass spectrum is recorded as a series of lines or peaks of relative abundance (vertical peak intensity) versus m/z ratio. The sample is introduced into the inlet system, where it is heated and vaporized under vacuum, and then bled into the ionization chamber (ion source) through a small orifice. Sample sizes for liquids and solids range from milligrams to less than a nanogram, depending on the detection limits of the instrument. Once the gas stream from the inlet system en ters the ionization chamber, it is bombarded at right angles by an electron beam (70 eV) emitted from a hot filament. Only Ëœ20eV is needed to remove one electron from the molecule, to create M+, the remainder is used to fragment the molecular ion into a mixture of radical cations, cations and free radicals. The positively charged ion fragments are then forced through a series of negatively charged accelerating slits towards the mass analyser, where separation of these ion fragments takes place. This analyser tube is an evacuated curved metal tube through which the ion beam passes from the ion source to the ion collector. In early instruments, the fragment ions were deflected in a curved path by a magnetic field only. Mass separation depended on the magnetic field strength, the radius of curvature of the magnetic field and the magnitude of the acceleration voltage. The introduction of an electrostatic field after the magnetic field in later instruments permitted higher resolution so that the mass readings could be obtained to four decimal places. In present day instruments, this double focusing system has been further modified to optimize resolution and most instruments now use a quadrupole mass analyser to effect separation of the ion fragments. The ions are collected one set at a time, with the aid of collimating slits, in the ion collector, where they are also detected and amplified by an electron multiplier. Mass spectral data is recorded on computer. Most mass spectrometers are computer controlled nowadays, and scans from mass ranges 12 to > 700 amu, Can be performed in seconds. [4] Figure: schematic diagram of mass spectrometry 4. Instrumentation of GC-MS The insides of the GC-MS, with the column of the gas chromatograph in the oven on the right. The GC-MS is composed of two major building blocks: the gas chromatograph and the mass spectrometer. The gas chromatograph utilizes a capillary column which depends on the columns dimensions (length, diameter, film thickness) as well as the phase properties (e.g. 5% phenyl polysiloxane). The difference in the chemical properties between different molecules in a mixture will separate the molecules as the sample travels the length of the column. The molecules take different amounts of time (called the retention time) to come out of (elute from) the gas chromatograph, and this allows the mass spectrometer downstream to capture, ionize, accelerate, deflect, and detect the ionized molecules separately. The mass spectrometer does this by breaking each molecule into ionized fragments and detecting these fragments using their mass to charge ratio. Figure: GC-MS schematic These two components, used together, allow a much finer degree of substance identification than either unit used separately. It is not possible to make an accurate identification of a particular molecule by gas chromatography or mass spectrometry alone. The mass spectrometry process normally requires a very pure sample while gas chromatography using a traditional detector (e.g. Flame Ionization Detector) detects multiple molecules that happen to take the same amount of time to travel through the column (i.e. have the same retention time) which results in two or more molecules to co-elute. Sometimes two different molecules can also have a similar pattern of ionized fragments in a mass spectrometer (mass spectrum). Combining the two processes makes it extremely unlikely that two different molecules will behave in the same way in both a gas chromatograph and a mass spectrometer. Therefore when an identifying mass spectrum appears at a characteristic retention time in a GC-MS analysis, i t typically lends to increased certainty that the analyte of interest is in the sample. [6] Figure: schematic of GC/MS 4.1 Inlet system Samples are introduced to the column via an inlet. This inlet is typically injection through a septum. Once in the inlet, the heated chamber acts to volatilize the sample. [6] 4.1.1 GC-MS interface In this GC-MS system, the link between the two instruments is called an interface; it is like a jet separator, whose purpose is to (1) enrich the sample and (2) adjust the vacuum to the high vacuum conditions needed for MS analysis of the column eluent. [11, 9] After separation of our components by the GC, we need away to introduce this sample into MS- interface. An ideal interface should be Qualitatively transfer all analyte Reduce pressure flow/from chromatograph to level MS can handle Not cost an arm (or a leg) No interface meets all requirements The major goal of the interface is to remove all of the carrier gas from- the majority of the effluents. Interface should cover Molecular separator Permeation separator Open split Capillary direct [7] 4.1.2 Molecular separator It is the most popular approach when packed columns are used and based on the relative rate of diffusion. In this the smaller molecules will diffuse more rapidly and most will miss the MS entry jet. The larger molecules will diffuse more slowly will tend to lead the MS entry jet. [7, 11] Figure: molecular separator Advantages of molecular separator It is relatively simple and inexpensive approaches Disadvantages Rate of diffusion is molecular weight dependent If jet becomes partially plugged, you can end up with an excellent carrier gas detector [7] 4.1.3 Permeation interface A semi permeation membrane is placed between the GC effluents and the MS The major problem with this approach is Membrane selectively based on polarity and the molecular weight slow to respond. Only a small fraction analyte actually permeates through the membrane. [7] Figure: permeation membrane 4.1.4 Open or split interface In a split system, a constant flow of carrier gas moves through the inlet. A portion of the carrier gas flow acts to transport the sample into the column. [6] The chromatographic column leads to a T-shaped that contains a smaller diameter tube. A platinum or deactivated fused silica capillary also leads to this tube and goes into the mass spectrometer source. The capillary is kept into the vacuum sealed device and is heated to avoid condensation. The T-shaped tube is closed at both ends but is not sealed, so that pressure remained equal to the atmospheric pressure. A helium gas is continuously passed to avoid any reaction of the gas. [9] The MS pulls the analyte in about 1mL/min through a flow restrictor. If flow is above that the excess is vented. If it is below the He from the external source is pulled in. it is the best source for that have flows close to1mL/min like capillary columns.[7] Figure: open or split interface Advantages Any gas producing source will be used. Relatively low cost and easy to use. Disadvantages Sample leaves columns in split. Split changes as flow change. Split system is preferred when the detector is sensitive to trace amounts of analyte and there is concern about overloading the column [7] 4.1.5 Capillary direct interface This coupling consists of having the capillary column directly entering the spectrometer source by a set of vacuum- sealed joints. Here the pumping is not the problem because the capillary is very long. A length of at least 1.5m is necessary for the column with inside diameter of 0.25mm. [9] If we limit the GC to the capillary column only, the MS can actually use all column effluents. [7] The carrier gas flow gets directed to purge the inlet of any sample following injection (septum purge). Yet another portion of the flow is directed through the split vent in a set ratio known as the split ratio. [6] Figure: capillary direct interface Advantages Low cost simple device No dead volume No selectivity Disadvantages Limits flow range that column can be used Limits the column ID that can use Part of column lost which serve as a flow restrictor[7] 4.2. Vacuum system In order to the MS process to work, it must be conducted under vacuum condition. The major reason for this is to increase the mean free path. The average distance that ions or molecules will travel before colliding with another ion or molecule. A high mean free path is to ensure predictable and reproducible high sensitivity and reliable mass analysis. [7] Since a vacuum is required to work a detector; Detectors are design to use the vacuum as an insulator Large voltage are used in the MS Operation of the detector in the absence of the vacuum that can cause severe damage Most instrument prevent operation if the vacuum is not high enough A vacuum is produced by using a combination of the two pumps- two stage vacuum pumps. The rotary pumps produced vacuum 102-104torr. These are the turbomolecular or diffusion pumps work in the range of 105torr. These are actually like the compressor. 4.2.1 Turbomolecular pump It relies on the series of blades or the air foils that tend to deflect the gas. It able to produce the clean vacuum in few hours and reliable Disadvantage It is expensive, short life time, can become noisy Figure: turbomolecular pump 4.2.2 Oil diffusion pumps It is another important type of the pump that produce high vacuum. These are reliable, maintenance free and quite but take much time and due to poor design oil enters into the vacuum. [7] Figure: oil diffusion pumps 4.3. Ionization A number of ionization techniques available Figure: types of ionization 4.3.1 Types of ionization After the molecules travel the length of the column, pass through the transfer line and enter into the mass spectrometer they are ionized by various methods with typically only one method being used at any given time. Once the sample is fragmented it will then be detected, usually by an electron multiplier diode, which essentially turns the ionized mass fragment into an electrical signal that is then detected. The ionization technique chosen is independent of using Full Scan or SIM. [6] 4.3.1.1 Electron Ionization By far the most common and perhaps standard form of ionization is electron ionization (EI). The molecules enter into the MS (the source is a quadrupole or the ion trap itself in an ion trap MS) where they are bombarded with free electrons emitted from a filament, not much unlike the filament one would find in a standard light bulb. The electrons bombard the molecules, causing the molecule to fragment in a characteristic and reproducible way. This hard ionization technique results in the creation of more fragments of low mass to charge ratio (m/z) and few, if any, molecules approaching the molecular mass unit. Hard ionization is considered by mass spectroscopists as the employ of molecular electron bombardment, whereas soft ionization is charge by molecular collision with an introduced gas. The molecular fragmentation pattern is dependant upon the electron energy applied to the system, typically 70eV (electron Volts). The use of 70eV facilitates comparison of generated spectra with Na tional Institute of Standard (NIST-USA) library of spectra applying algorithmic matching programs and the use of methods of analysis written by much method standardization Chemical Ionization. [6, 10] Figure: EI graph Figure: EI source 4.3.1.2 Chemical Ionization In chemical ionization a reagent gas, typically methane or ammonia is introduced into the mass spectrometer. Depending on the technique (positive CI or negative CI) chosen, this reagent gas will interact with the electrons and analyte and cause a soft ionization of the molecule of interest. A softer ionization fragments the molecule to a lower degree than the hard ionization of EI. One of the main benefits of using chemical ionization is that a mass fragment closely corresponding to the molecular weight of the analyte of interest is produced. Figure: CI source Positive chemical Ionization In Positive Chemical Ionization (PCI) the reagent gas interacts with the target molecule, most often with a proton exchange. This produces the species in relatively high amounts. Negative Chemical Ionization In Negative Chemical Ionization (NCI) the reagent gas decreases the impact of the free electrons on the target analyte. This decreased energy typically leaves the fragment in great supply. [6, 7] Figure: comparison of graph obtain from EI and CI 4.4 Mass analyzer A mass analyzer or filter is the portion of the mass spectrometer that is responsible for resolving different mass fragments. Typically all ions will move with same kinetic energy (1/2mv2). Some aspects of these accelerated ions are exploited as the basis for resolving them. 4.4.1 Types of mass analyzers There are following types of mass analyzers Magnetic Electrostatic Time of flight Quadrupole mass filter Quadrupole ion storage(ion trap) The last two types are most commonly used in GC/MS systems although time of flight making a come back [7, 6, 10] 4.4.1.1 Quadrupole mass filter It consists of four rods. Figure: rods of quadrupole Rods operate in pairs (x or y) and each carries a voltage. Only ions of proper m/z value can successfully traverses the entire filter (z axis). The high pass rods filter out ions with too low of an m/z. the low pass filter outs the ions with too high of an m/z value. [7] Figure: schematic of quadrupole 4.5 Detector Ion detection Once the ions are separated, we need a way to convert them to a response that can be used. An electron multiplier is the most common type of detector used. It is a continuous dynode type of detector. The inner surface of the detector is electroemassive material. When struck by ion electrons are ejected. Due to increasing potential, the electrons are accelerated and when they strike another surface, even more electrons are ejected. This significantly amplifies our signals. [7] Figure: detector 4.6 Data system Data system is the heart of our GC/MS system. Without it we would have no way to deal with the vast amount of information that even a single GC/MS analysis produce. Inexpensive fast desktop are the single most important advance in GC/MS. [7] Figure: data system 4.7 Method of analysis The primary goal of instrument analysis is to quantify an amount of substance. This is done by comparing the relative concentrations among the atomic masses in the generated spectrum. Two kinds of analysis are possible, comparative and original. Comparative analysis essentially compares the given spectrum to a spectrum library to see if its characteristics are present for some sample in the library. This is best performed by a computer because there are a myriad of visual distortions that can take place due to variations in scale. Computers can also simultaneously correlate more data (such as the retention times identified by GC), to more accurately relate certain data. Another method of analysis measures the peaks in relation to one another. In this method, the tallest peak is assigned 100% of the value, and the other peaks being assigned proportionate values. All values above 3% are assigned. The total mass of the unknown compound is normally indicated by the parent peak. The value of this parent peak can be used to fit with a chemical formula containing the various elements which are believed to be in the compound. The isotope pattern in the spectrum, which is unique for elements that have many isotopes, can also be used to identify the various elements present. Once a chemical formula has been matched to the spectrum, the molecular structure and bonding can be identified, and must be consistent with the characteristics recorded by GC/MS. Typically, this identification done automatically by programs which come with the instrument, given a list of the elements which could be present in the sample. A full spectrum analysis considers all the peaks within a spectrum. Conversely, selective ion monitoring (SIM) only monitors selected peaks associated with a specific substance. This is done on the assumption that at a given retention time, a set of ions is characteristic of a certain compound. This is a fast and efficient analysis, especially if the analyst has previous information about a sample or is only looking for a few specific substances. When the amount of information collected about the ions in a given gas chromatographic peak decreases, the sensitivity of the analysis increases. So, SIM analysis allows for a smaller quantity of a compound to be detected and measured, but the degree of certainty about the identity of that compound is reduced. [6] 5. Applications 5.1. Environmental Monitoring and Cleanup GC-MS is becoming the tool of choice for tracking organic pollutants in the environment. The cost of GC-MS equipment has decreased significantly, and the reliability has increased at the same time, which has contributed to its increased adoption in environmental studies. There are some compounds for which GC-MS is not sufficiently sensitive, including certain pesticides and herbicides, but for most organic analysis of environmental samples, including many major classes of pesticides, it is very sensitive and effective. 5.2. Criminal Forensics GC-MS can analyze the particles from a human body in order to help link a criminal to a crime. The analysis of fire debris using GC-MS is well established, and there is even an established American Society for Testing Materials (ASTM) standard for fire debris analysis. GCMS/MS is especially useful here as samples often contain very complex matrices and results, used in court, need to be highly accurate. 5.3. Law Enforcement GC-MS is increasingly used for detection of illegal narcotics, and may eventually supplant drug-sniffing dogs. It is also commonly used in forensic toxicology to find drugs and/or poisons in biological specimens of suspects, victims, or the deceased. 5.4. Security A post-September 11 development, explosive detection systems have become a part of all US airports. These systems run on a host of technologies, many of them based on GC-MS. There are only three manufacturers certified by the FAA to provide these systems, one of which is Thermo Detection (formerly Thermedics), which produces the EGIS, a GC-MS-based line of explosives detectors. The other two manufacturers are Barringer Technologies, now owned by Smiths Detection Systems and Ion Track Instruments, part of General Electric Infrastructure Security Systems. 5.5. Food, Beverage and Perfume Analysis Foods and beverages contain numerous aromatic compounds, some naturally present in the raw materials and some forming during processing. GC-MS is extensively used for the analysis of these compounds which include esters, fatty acids, alcohols, aldehydes, terpenes etc. It is also used to detect and measure contaminant from spoilage or adulteration which may be harmful and which is often controlled by governmental agencies, for example pesticides. 5.6. Astrochemistry Several GC-MS have left earth. Two were brought to Mars by the Viking program. Venera 11 and 12 and Pioneer Venus analysed the atmosphere of Venus with GC-MS. The Huygens probe of the Cassini-Huygens mission landed one GC-MS on SaturnHYPERLINK http://en.wikipedia.org/wiki/SaturnsHYPERLINK http://en.wikipedia.org/wiki/Saturnss largest moon, Titan. The material in the comet 67P/Churyumov-Gerasimenko will be analysed by the Rosetta mission with a chiral GC-MS in 2014. 5.7. Medicine In combination with isotopic labeling of metabolic compounds, the GC-MS is used for determining metabolic activity. Most applications are based on the use of 13C as the labeling and the measurement of 13C/12C ratios with an isotope ratio mass spectrometer (IRMS); an MS with a detector designed to measure a few select ions and return values as ratios. [6]

Aristotle and Aquinas Essay -- Philosophy essays

Aristotle and Aquinas      Ã‚  Ã‚   Among political theorists, the debate over the rule of law has been quite intense.   From the earliest days of political philosophy through to the enlightenment, there have been varying views on what the rule of law should be.   Two thinkers in particular - Aristotle and St. Thomas Aquinas - are perhaps the most influential.   On the surface, they both advocate the rule of law as playing a crucial role in society.   But upon deeper analysis, one finds that Aristotle's views sharply contrast with those of Aquinas.   This essay shall attempt to elucidate the disagreement between Aristotle and Aquinas, by first outlining Aristotle's arguments for and against the rule of law, and then by explaining what Aristotle would find inadequate with Aquinas' arguments.      In the third book of Politics (1286a8ff.), Aristotle presents a number of arguments for and against the rule of law.   He begins by posing a question around which his ensuing discussion revolves:    The beginning point of the inquiry if this:   whether it is more advantageous to be ruled by the best man or by the best laws.1    He proceeds to point out that laws only speak of the universal, and that they "do not command a view to circumstance"2   He uses the analogy of an Egyptian doctor to prove his point.   In Egypt, a doctor must follow legal procedure when treating a patient.   It is only after the fourth day that the doctor is legally permitted to use his or her own discretion, and even then, it is at his or her own risk.   Thus, the doctor must follow the prescribed routine (until the fourth day), even if it leads to the death of his patient.   Aristotle uses this example to illustrate that the best regime cannot be one that i... ...le by law, or to fool by law;   that is the question.   And the debate still rages on.    BIBLIOGRAPHY: Lord, Carnes [trans.]   Aristotle, The Politics.   University of Chicago Press; Chicago;   1985 Baumgarth, William P. and Richard J. Regan [eds.]   Aquinas, St. Thomas.   On Law, Morality, and Politics.   Hackett Publishing Company, Indiana;   1998       1 Lord, Carnes [trans.] - Aristotle, The Politics.   P. 111 Ln. 8-9 2 Ibid.  Ã‚   Ln. 11-12 3 Ibid.  Ã‚   Ln. 20-21 4 Ibid.  Ã‚   Ln. 30 5 Ibid.  Ã‚   Ln. 35 6 Ibid.   Pp. 111-112.   Ln.36-37 7 Ibid.   P. 112.   Ln. 2 8 Ibid.  Ã‚   Ln.6 9 Ibid.   P. 114.   Ln 28 10 Ibid.   P. 115.   Ln. 4-5 11 Baumgarth, William P. and Richard J. Regan [eds.]   Aquinas, St. Thomas.   On Law, Morality, and Politics.   P. 57 12 Ibid.  Ã‚   Pp. 57-58 13 Ibid.  Ã‚   P. 58 14 Ibid.  Ã‚   P. 116.   Ln. 28