What to Know About Zeta Potential

What to Know About Zeta Potential The zeta potential (ÃŽ ¶-potential) is the potential difference across phase boundaries between solids and liquids. Its a measure of the electrical charge of particles are that are suspended in liquid. Since zeta potential is not equal to the electric surface potential in a double layer or to the Stern potential, it is often the only value that can be used to describe double-layer properties of a colloidal dispersion. Zeta potential, also known as electrokinetic potential, is measured in millivolts (mV). In colloids, zeta potential is the electric potential difference across the ionic layer around a charged colloid ion. Put another way; its the potential in the interface double layer at the slipping plane. Typically, the higher the zeta-potential, the more stable the colloid. Zeta potential that is less negative than -15 mV typically represents the beginnings of agglomeration of particles. When the zeta-potential equals zero, the colloid will precipitate into a solid. Measuring Zeta Potential Zeta potential cannot be directly measured. It is calculated from theoretical models or estimated experimentally, often based on electrophoretic mobility. Basically, to determine zeta potential, one tracks that rate at which a charged particle moves in response to an electric field. Particles that possess a zeta potential will migrate toward the opposite-charged electrode. The rate of migration is proportional to zeta potential. Velocity typically is measured using a Laser Doppler Anemometer. The calculation is based on a theory described in 1903 by Marian Smoluchowski. Smoluchowskis theory is valid for any concentration or shape of dispersed particles. However, it assumes a sufficiently thin double layer, and it ignores any contribution of surface conductivity. Newer theories are used to perform electroacoustic and electrokinetic analyses under these conditions. There is a device called a zeta meter its expensive, but a trained operator can interpret the estimated values that it produces. Zeta meters typically rely on one of two electroacoustic effects: electric sonic amplitude and colloid vibration current. The advantage of using an electroacoustic method to characterize zeta potential is that the sample does not need to be diluted. Applications of Zeta Potential Since the physical properties of suspensions and colloids largely depend on the properties of the particle-liquid interface, knowing the zeta potential has practical applications. Zeta Potential Measurements are used to Prepare colloidal dispersions for cosmetics, inks, dyes, foams, and other chemicalsDestroy undesirable colloidal dispersions during water and sewage treatment, preparation of beer and wine, and dispersing aerosol productsReduce cost of additives by calculating the minimum amount needed to achieve the desired effect, such as the amount of flocculant added to water during water treatmentIncorporate colloidal dispersion during manufacturing, as in cements, pottery, coatings, etc.Utilize desirable properties of colloids, which include capillary action and detergency. Properties may be applied for mineral flotation, impurity absorption, separating petroleum from reservoir rock, wetting phenomena, and electrophoretic deposition of paints or coatingsMicroelectrophoresis to characterize blood, bacteria, and other biological surfacesCharacterize the properties of clay-water systemsMany other uses in mineral processing, ceramics manufacturing, electronics manufacturing, pharmaceutical producti on, etc. References American Filtration and Separations Society, What Is Zeta Potential? Brookhaven Instruments, Zeta Potential Applications. Colloidal Dynamics, Electroacoustic Tutorials, The Zeta Potential (1999). M. von Smoluchowski, Bull. Int. Acad. Sci. Cracovie, 184 (1903). Dukhin, S.S. and Semenikhin, N.M. Koll. Zhur., 32, 366 (1970).

Restrictive and Unrestrictive Use of Such As

Restrictive and Unrestrictive Use of Such As Restrictive and Unrestrictive Use of Such As Restrictive and Unrestrictive Use of Such As By Mark Nichol The phrase â€Å"such as† comes in handy for referring to specifics, but whether it begins a longer phrase framed by a pair of commas depends on whether that longer phrase is essential to the sentence or is provided as additional but nonessential information. The following sentences demonstrate erroneous use or omission of punctuation with the phrase; discussion and revision indicate correct usage. 1. In circumstances, such as these, are our strengths and weaknesses revealed. A pair of commas around â€Å"such as these† presumes that the phrase is optional, but â€Å"In circumstances are our strengths and weaknesses revealed,† though a valid statement, misses the point of the sentence, which is intended to relate the sentiment to a particular set of circumstances, so the phrase is essential and should not be set off: â€Å"In circumstances such as these are our strengths and weaknesses revealed.† 2. The use of the technology allows companies, such as World Wide Wickets, to transfer funds faster, cheaper, and in a trackable mechanism. Out of context, it may not be clear whether the parenthesis is necessary, but when one accepts the assumption that the company has already been mentioned, the phrase seems oddly intrusive when treated as an interjection, while its integral placement in the statement is natural: â€Å"The use of the technology allows companies such as World Wide Wickets to transfer funds faster, cheaper, and in a trackable mechanism.† 3. Specific employee information, such as Social Security numbers and I-9 forms for employment eligibility must be transferred in accordance with law. The examples given in this sentence are helpful but not essential, so the phrase beginning with â€Å"such as† and ending before the verb phrase â€Å"must be transferred† should be treated parenthetically. This sentence starts off correctly but neglects to close off the parenthesis with a second comma: â€Å"Specific employee information, such as Social Security numbers and I-9 forms for employment eligibility, must be transferred in accordance with law.† (The sentence is also correct without internal punctuation.) 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 Style category, check our popular posts, or choose a related post below:Passed vs Past45 Synonyms for â€Å"Old† and â€Å"Old-Fashioned†The Difference Between "Shade" and "Shadow"

The Virgin Mary painting Essay Example | Topics and Well Written Essays - 2250 words

The Virgin Mary painting - Essay Example The essay "The Virgin Mary painting" explores the importance of religion in Mexican art ad discovers The Virgin Mary painting. The Virgin Mary also has a very prominent position in the religious art of Mexico and this is mainly because of the fact that she is highly venerated in the country with many Mexicans considering her to be the mother of the entire nation. In addition, many Mexicans during their prayers seek the help of the Virgin Mary as they ask her to intercede to God and Jesus on their behalf and this has ensured that she has come to be revered by all the people in the nation. The prominence of the Virgin Mary in the national psyche has ensured that she is also given a prominent position in art, because Mexican artists, like all Mexican people, are very devoted to her. This has led to a situation where most of the art in the country has some religious aspect in one way or the other and this has ensured that the religious spirit of Mexican artwork has remained prevalent wit h little sign of its diminishing in the coming years. Religion has been a source of inspiration for Mexican art for many years and it is for this reason that a large number of art that it produced in this country, even that in the secular realm, has some aspect of religion within it. As has been mentioned above, Roman Catholicism is the most dominant religion within Mexico and this has been the case since the founding of the state after the Spanish conquest. However, it has been found that the Catholicism is highly syncretic.

Prediction of OECD Regarding Budget Deficit in the USA Economy Research Paper

Prediction of OECD Regarding Budget Deficit in the USA Economy - Research Paper Example It is estimated that the standard principal deficit in the USA will be 2% of the total Gross Domestic Product (GDP) in 2015 and will increase to 7.7% of total GDP by 2035. The baseline debt of the USA was 65% of total GDP in 2010, which is estimated to become 213% by 2035 (Gagnon & Hinterschweiger, 2011). A budget deficit occurs when the government expands excess amount compared to what it gains through taxation. The opposite terminal of the budget deficit is budget surplus when the outgoings are less than the receiving amount (Investopedia ULC, 2011). Even a few years back, the US had a budget surplus but due to the impact of the crisis in present days, the US economy is running with a budget deficit of 10% on GDP. It is expected that the budget deficit will decrease to 7% of GDP and by 2017 the government will seek to reduce the budget deficit to 3% of GDP (Paletta & Boles, 2011). Deficit reduction plan is helpful for advanced economies to deal with the economic recession. Several nations have implemented the debt reduction strategy to maintain a justifiable fiscal budget and to reduce the debt. Deficit reduction strategy can result in a change of major economic and monetary players. It can help to achieve prospects of creditors which can ultimately reduce the financing budgets. It can be achieved by minimizing risk premium through ‘higher long-term interest’ (OECD, 2010). Deficit Reduction in Greek Government The Greek government had followed the deficit reduction plan in order to reduce their huge amount of deficits. In the year 2009, the deficit of Greece was 15.4% of GDP. The government of Greece had estimated a deficit of 9.4% in 2010. In order to reduce the deficit, Greece had adjusted its economic settings. The objective of deficit plan of Greece is to reduce government budget by decreasing expenses on public pays, annuities on the public as well as private segments, and raise the revenue by increasing the rate of Value Added Tax (VAT), an d taxes on gasoline, alcohol, and tobacco products. Greece’s deficit plan was to receive financial support from the EU nations and the International Monetary Fund (IMF). Through this financial support, it is estimated that Greece can improve economic growth and reduce the debt crisis. But, the deficit plan can have certain negative impacts on the economy. Reducing the monetary expenses can lead to falling on the value of the currency and stock market. Increasing taxes can also harm the lifestyle of people and can impact on the demand of products which may increase the problem of crisis. However, those who support the deficit plan say that delay in consolidating debt can worsen the economic condition even further (McCully & Webb, 2010). Deficit Reduction by Irish Government The debt crisis of Ireland is not similar as Greece, as it did not occur due to excess expenditures; rather it had occurred due to the promising housing bubble in certain Irish banks.

A Comparison of The Chrysalids and 1984 :: comparison compare contrast essays

   A comparison of life in London, Air Strip One (or Great Britain) in the George Orwell novel '1984' and Waknuk, Canada in the John Wyndham novel 'The Chrysalids.' Waknuk is a society living after a nuclear attack. The people of Air Strip One (or Britain) in 1984 live in a dictatorship controlled by "The Party".      Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Waknuck is an enclosed society similar to Victorian Britain. As people spend all their lives in the town or city they are born they can't experience different cultures and therefore have a lack of tolerance and understanding for differences in the lifestyles of these cultures. The lack of experience of different cultures is not the reason for a lack of a true understanding of these cultures in 1984. The people of London are effectively poisoned against such cultures by the Party and so have no reason to want to experience them.  Ã‚        Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚     Waknuck is also based largely on Religion - it is a Christian society. Most of the prejudices are formed from the Bible. Any creature that is against "the true image of God" (or a mutant) is called a Blasphemy. The Christian religion (and indeed other religions) have been the source of numerous prejudices in modern society in Britain (for example sexism and homophobia) and indeed conflicts (for example the conflicts between the Republic and Northern Ireland). In the novel '1984' no-one follows a religion as such, as far as the people of Britain in 1984 are concerned there is no God, the complete opposite of the radical religious views of the people of Waknuk. Most people in Waknuk have been 'brainwashed' by Christianity in the same way many people in Great Britain in 1984 have been 'brainwashed' by the party and Big Brother. Each use repetitive slogans, in 1984 such slogans as: "War is peace. Freedom is slavery. Ignorance is strength." are used and more subtly in Christianity in the form of prays and commandments. The Party and Christians each worship a figure, Big Brother and God respectively, neither people can be completely sure of   there presence but convince themselves that they exist nevertheless. The power lies with the Party in 1984 but lies with the church in Waknuk.         Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   The people of Waknuk are unable to comprehend theories such as the Evolution Theory dispute finding fossils and other evidence that would conflict with Genesis.

Rhitorical Appeals in Literature Essay

In â€Å"Superman and Me† by Sherman Alexie, the narrator’s claim is that if you do your best to obtain knowledge, even those considered to be low class can flourish and rise up in a world such as ours. In this specific case, the narrator turns his quest for knowledge into a fight to improve his life as well as the lives of his fellow Indian’s. He read whenever possible in hopes that he could escape the poverty of the reservation and make something of himself, unlike the other kids who purposely did bad in class and pretended to be stupid. Sherman Alexie uses the rhetorical appeal of Pathos, or emotion, as well as Ethos, to get his point across. He writes about how when he was a kid, no one was there to help them in school and teach them how to write properly, and how as an adult he Is continuously fighting to help kid’s in the same situation he was once in so that they do not have to go through what he did to succeed and become successful in life. There is no better interpretation of what Alexie is trying to prevent or solve as he himself was in the same situation that he is fighting to end to this day. He says â€Å"I am smart. I am arrogant. I am lucky. I am trying to save our lives† (Alexie Phar. 8). Throughout his essay, he shows how using his knowledge, arrogance, and luck he manages to â€Å"break out† of the Indian reservation to become a successful writer in an attempt at saving â€Å"our† lives: Not just his life, but the lives of all Indians, both current and future. In the poem â€Å"Crazy Courage† by Alma Luz Villanueva, the author talks about a man named Michael that she met in her fiction class, who, as she later finds out, is a cross dresser. Using the rhetorical appeal Pathos, the author  truly proves her point- that other people’s opinions do not matter so long as you are courageous and confident about yourself. In the poem, Michael seems so courageous, even though he is dressed in woman’s clothes and in front of an entire class, that it â€Å"shocked / the young, seen-it-all MTV crowd / into silence†(Villanueva 20-23). The class was so shocked at the confidence of the person in front of them considering his situation that they couldn’t even speak. In fact, even â€Å"those who would kill him† were impressed at the level of courage he must have had, and the fact that he seemed even happier in the seemingly odd clothes and outfit he was wearing (Villanueva 27). Last but not least is the poem â€Å"Theme for English B† by Langston Hughes. The author Langston Hughes seems to use more of a Logical appeal. While it doesn’t seem to be the most organized Poem, there is without a doubt some sort of claim. While it isn’t necessarily the best example of a claim that relates to knowledge and individual power, it seemed like an interesting poem to write about. In my opinion, the author is trying to show that even though he is of a different race than his white teacher, and even though he is from Harlem, he is just like everyone else. He likes â€Å"to eat, sleep, drink, and be in love. / [He] like[s] to work, read, learn, and understand life†(Hughes 21-22). On the other hand, I feel like this poem has a hidden message, which is that obtaining knowledge is important for him to eventually become as â€Å"free† as his older, white teacher. That is why, in my opinion, he mentions where he went to school and the fact that he is in college to learn, in hopes of getting somewhere in the long run. That is also why, in my opinion, he points out that he is the only colored student in his class. Not necessarily to point out his color or race, but to show that he is one of the few in his race that finds knowledge to be an important thing. Overall, I feel like all of these claims are somewhat valid. The claims in â€Å"Crazy Courage† and â€Å"Superman and Me† are without a doubt true in my opinion, however the claim in â€Å"Theme for English B† seems a bit weak. I’m not quite sure when the third poem was written, however nowadays I feel like the level of colored people obtaining an education is relatively fair. Racism is for the most part nonexistent in at least the northern half of the United States, so that is no longer a problem in our  society here. I feel like if the poem was written recently it would not have been as successful as it was, and you wouldn’t be finding it in text books. Perhaps the poem was written a long time ago so the authors points were valid, however nowadays plenty of colored people are receiving proper educations and going to college.

The First Amendment And Freedom Of Speech - Free Essay Example

Sample details Pages: 4 Words: 1250 Downloads: 6 Date added: 2019/04/26 Category Law Essay Level High school Tags: First Amendment Essay Did you like this example? For the most part, freedom of speech is the freedom to speak on any subject. There is an exception to the First Amendment, and these categories are obscenity, child pornography, fighting words, speech integral to criminal conduct, and incitement to immediate unlawful action. They are not protected under the First Amendment, therefore are punishable based on content. The lack of protection from the First Amendment protects children from people trying to exploit them, protects a group or single person from injury due to incitement or fighting words, and protect individuals from blackmails and extortion. Context is very important component of speech. These categories have well-defined boundaries and there are more that are unprotected, but dont pertain to police officers. The Supreme Court took 15 years after obscenity was declared unprotected by the first Amendment to develop a constitutional definition. Obscenity is tested by the Miller test. This test shows obscenity if i t appeals to the prurient, which is defined as an interest in sex, of the average person, illustrates hard-core sexual acts, and lacks any literary, political, artistic, scientific, or other value. The Miller test identifies specific hard-core sexual acts that must be established before it is considered obscene. If a piece has value it is not considered obscene even if they portray sexual activity. Child pornography is excluded because of the need to protect children from being exploited and sexual abused. Child pornography does not have to appease the obscenity portion of the Miller test. The first legislation for child pornography was passed in 1977. Since then, Congress has toughened statutes on child protection laws. As the internet progressed, Congress began to talk about child pornography on computers. Allowing children to view pornography allows adults to entice children into sexual activity. Other concerns brought to Congress was it was a moral concern too. Congresss first a ction in this area was its passage of the Communications Decency Act of 1996 (CDA), which attempted to incorporate the Miller obscenity test and sought to limit the exposure of children to sexually explicit material on the Internet (Ward, para. 6). Fighting words are not excluded from the First Amendment for communicating ideas, insulting or offensive language. People have a right to say provocative things if they so choose. Fighting words are classified as to purely inflict injury, as the book stated. There are no set words that are automatically categorized as fighting words. Fighting words are highly debated, especially when it comes to police officers. The Supreme Court has made it unconstitutional to arrest someone who verbal attacks a police officers because they are trained to not react physical and therefore it would not be considered fighting words. The incitement to riot is depended upon if the words used in that situation creates a present danger. The Congress has a ri ght to prevent such acts. The Supreme Court has said that for speech to lose First Amendment protection, it must be directed at a specific person or group and it must be a direct call to commit immediate lawless action (Incitement to Imminent, 2008). True threat is a speech that is meant to intimidate one or more specific people. The court does not have defined boundaries and have only used this defense in a couple of cases. One case in which true threat was upheld was Virginia v. Black. The Supreme Court stated that states could criminalize cross burning if they could prove it was a threat and not a form of expression. A stipulation with the true threat category is that it doesnt have to be proved that one intends to carry out the threat, but that one communicated a threat. One complication is that the Supreme Court has defined the level of intent that is required for prosecuting true threat. Considering the list of unprotected speech, I dont think I would add or take away any. They are all very valid with what I would deem acceptable. The First Amendment allows citizens to criticize the government and voice unpopular opinions and the very few stipulations to that law is warranted. The federal government passed a law to restrict freedom of speech in 1978. Congress thought that people would be sympathetic to France during the war, so the Sedition Act was passed. Many people were against the Sedition Act and it was never challenged before the Supreme Court. By 1801 the act expired, and Thomas Jefferson pardoned all those convicted under the law. The second attempt to restrict freedom of speech was in 1917 when Congress passed the Federal Espionage Act. This prohibited false statements that interfered with military forces of the country or promoted the success of enemy forces. The Supreme Courts first decision in the area of free speech was in the case of Schenck vs. the United States, in which Justice Holmes wrote the opinion which sided with the governme nt. He stated, When a nation is at war, many things that might be said in time of peace are such a hinderance to its efforts that their utterance will not be endured so long as men fight and that no Court could regard them as protected by any Constitutional right (Costly, para. 12). His view was limited to times of war, which clearly alter many different laws and government views. This one issue created many others, which raised the question what clear and present danger means and when it should stop people from saying certain things. The Supreme Court established the clear and present danger test in the 20th century to determine when speech is protected by the First Amendment (Parker, para. 1). The clear and present danger doctrine played a major role in the Constitutions beginning. It was placed to limit speech against the government. I think this is because government was so new that they wanted to make sure that everyone was on the same page and if they werent, make it to wh ere they couldnt be heard without prosecution. In later years, Justice Holmes wrote, we should be eternally vigilant against attempts to check the expression of opinions . . . unless they so imminently threaten immediate interference with the lawful and pressing purpose of the law that an immediate check is required to save the country (Parker, para. 8). His statement was after the case of Abram v. United States. In 1937, the clear and present danger test was accepted and between 1940-1951 it was used to decide twelve cases. In 1951, the presence of gravity of evil was introduced in the revised clear and present danger. Judge Learned Hand of the Second Circuit Court of Appeals adapted the revision in United States v. Dennis: Clear and present danger depends upon whether the mischief of the repression is greater than the gravity of the evil, discounted by its improbability (Parker, para. 16). The clear and present danger test has been revised and interpreted different ways dependi ng on circumstances of the nation. The test is no longer used and is superseded by the imminent lawless action. The people didnt like the danger test because it made it where it depended on judicial findings. Then the balancing test was in place which weighed the interest of speech. References Costly, A. (n.d.). A Clear and Present Danger. Retrieved November 26, 2018 Incitement to Imminent Lawless Action. (2008, May 12). Retrieved November 26, 2018 Kanovitz, J. R. (2015). Constitutional Law for Criminal Justice. New York: Routledge. ONeill, K. F., Jr, D. L. (2017, June). The First Amendment Encyclopedia. Retrieved November 26, 2018 Parker, R. (n.d.). The First Amendment Encyclopedia. Retrieved November 26, 2018 Ward, Artemus. The First Amendment Encyclopedia. Virginia and Kentucky Resolutions of 1798. Retrieved November 26,2018 Don’t waste time! Our writers will create an original "The First Amendment And Freedom Of Speech" essay for you Create order