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).

How to Manage and Maintain Paulownia tomentosa

How to Manage and Maintain Paulownia tomentosa An Introduction to Royal Paulownia: Royal Paulownia is a native of China where it is revered as a tree and loved for both its legends and its usability. The trees form is a bit ragged but can provide an enjoyable and dramatic, coarse-textured appearance with huge heart-shaped leaves and large clusters of lavender flowers in the spring. Paulownia flowers are usually set before leaf emergence so they really stand out against a neutral or evergreen background. With its very rapid growth rate, the princess-tree can reach 50 feet in height with an equal spread in an open landscape. Royal Paulownia Specifics: Scientific name: Paulownia tomentosaPronunciation: pah-LOE-nee-uh toe-men-TOE-suhCommon name(s): Princess-Tree, Empress-Tree, PaulowniaFamily: ScrophulariaceaeUSDA hardiness zones: 5B through 9Origin: not native to North AmericaUses: reclamation plant; tree has been successfully grown in urban areas where air pollution, poor drainage, compacted soil, and/or drought are commonAvailability: grown in small quantities by a small number of nurseries Invasive Exotic Status: Royal paulownia is a prolific seeder but not welcomed by many forest owners. Woody seed capsules form in autumn containing up to two-thousand seeds and can cover a large area using wind power. The seeds persist through the winter and have a high germination percentage. Seeds germinate readily in the landscape and because of this ability to take over a site, paulownia has been given invasive exotic tree status and planters are cautioned about its reproductive potential. Royal Paulownia Description: Height: 40 to 50 feetSpread: 40 to 50 feetCrown uniformity: irregular outline or silhouetteCrown shape: round; vase shapeCrown density: moderateGrowth rate: fastTexture: coarse Trunk and Branch Structure: Royal paulownias bark is thin and easily damaged from mechanical impact so be careful using equipment around the tree. Paulownia has a characteristic droop as the tree grows and will require pruning for vehicular or pedestrian clearance beneath its canopy. The tree is not particularly showy and to improve its appearance, should be grown with a single leader. There is a major pruning requirement: the tree needs regular pruning to develop a strong structure. Paulownia Foliage: Leaf arrangement: opposite/suboppositeLeaf type: simpleLeaf margin: entireLeaf shape: cordate; ovateLeaf venation: pinnate; palmateLeaf type and persistence: deciduousLeaf blade length: 8 to 12 inches; 4 to 8 inchesLeaf color: greenFall color: no fall color changeFall characteristic: not showy Pruning a Royal Paulownia: The Princess-Tree expresses rapid growth and can reach 8 feet in two years from seed. This causes frequent winter kill to tender growth. You will not find this to be a problem if you prune down to where an axillary bud can take over as the single leader. It is important to build a single leader as long as possible and there should be a clear stem to the first main branch at 6 feet or higher. This pruning process is especially important if you are wanting to utilize the tree for its wood. Royal Paulownia In Depth: Paulownia thrives best in deep, moist but well-drained soil that is sheltered from the wind. The tree has become naturalized in many parts of the southern United States so you can see them most anywhere in lower North American latitudes. Fuzzy, brown flower buds form in early autumn, persist over the winter and bloom in early spring. These buds may freeze in very cold weather and drop off. Woody seed capsules form in autumn containing up to two-thousand seeds. They can easily hibernate through the winter and germinate readily in the landscape or wherever they are carried. Leaves rapidly drop within one week following the first frost in autumn. Storm damage can be a problem as the tree is susceptible to breakage either at the crotch due to poor collar formation or the wood itself is weak and tends to break. It has no known insect enemies. There have been occasional reports of problems with mildew, leaf- spot and twig canker.

Successes, Failures and Politicization of Aid in Somalia 1991-2012 Dissertation

Successes, Failures and Politicization of Aid in Somalia 1991-2012 - Dissertation Example Due to the politics involved, the response to the needs of the people was very much delayed. Limited public interest in the crisis also led to issues in the distribution of aid. There has been much politicking in the UN agencies on the distribution of aid in Somalia (Hilhorst and Jansen, 2010). The UN processes were also ineffective as they were more process focused, not results focused. The strong competition with the NGOs also made things complicated. Risk adversity also became the principle of the humanitarian agencies. A contributing issue is accountability, where donors held the organizations responsible for what they did, and not carrying out sufficient crisis response measures for this issue (Warsame, 2012). The intense media scrutiny also presented problems and the aid agencies were delayed in their aid. Institutional interests were also given more importance than beneficiaries. The release of aid is still an industry; as proof small organizations which used to engage in aid are not multinational organizations with vast influence and budgets (Wiles, et.al., 2004). Through such changes, the need to protect the reputation of the company seems to take more importance. With the professionalization of the aid industry, the people manning such activities have also become professionalized. Careers have now been borne from such industry and the hiring of experienced personnel has become more important (Wiles, et.al., 2004). In some instances, lack of accountability was observed. With the gaps in the integrity of the system, the lack of soul-searching in the humanitarian community following the Somalia famine was unexpected. This may have been credited to the shortcomings in the system, alongside limited public and media interests which allowed the humanitarian community to persist with limited considerations made on their impact on Somalia (Wiles, et.al., 2004). A semblance of success in securing humanitarian aid in Somalia can be attributed to support gained f rom the civil society. However, even as civil society has a significant role to play in supporting unarmed civilians, civil society often suffers from limited support (IRIN News, 2009). In a 2009 appeal made by concerned civilian agencies seeking humanitarian aid in Somalia, their appeal amounted to $919 million, indicating increasing needs with allocations also requested for air transportation. The limits of the aid are based on the capacity and resources of the international community and there is a need to secure a partnership to fill in the gaps (IRIN News, 2009). The civil society has already paid significantly for their assistance to the poor. Access to south-central Somalia where the humanitarian needs are significant, much conflict has been seen especially with the abduction of aid workers (IRIN News, 2009). The security situation has not improved much for aid workers in the country. Two major NGOs have temporarily suspended their operations in the country and aid agencies h ave also been conflicted with the problem of piracy (IRIN News, 2009). Most times, humanitarian access has become unpredictable, and despite such issue, successful aid groups have still responded to the crisis. These agencies have understood that their responsibility to

German Essay Example | Topics and Well Written Essays - 1250 words - 1

German - Essay Example The wall’s real purpose was most likely to halt defection and emigration, which had marked The Eastern block of communism and Germany after the end of the Second World War. This paper aims to discuss the building, function, and fall of the Berlin wall. The Berlin wall separated the people of West Berlin and East Berlin for twenty-eight years. Following the end of World War two in the year 1945, the allies on victory divided Germany into four parts. These allies were Russia, the United States, France, and Britain. Each ally took control of one sector. The sectors taken over by the British, French, and the United States merged to form the federal Republic of Germany, or West Germany. The sector controlled by the Russians became a communist republic, East Germany or as it was then called the German Democratic Republic. This was ratified on October the 7th of 1949. This created an invisible barrier that separated the West from the East. Winston Churchill christened this barrier the Iron Curtain. Despite the fact that Berlin lay deep in Soviet territory, the allies had agreed to divide the city. This led to another quarterly subdivision. The French, British, and U. S. sectors merged to form the city of West Berlin, with the sector cont rolled by the Soviets becoming the capital of East Germany and being called East Berlin. These new countries were established, not by the general population, but by the occupying forces. While the communists ruled the eastern region, most of its residents were not happy with communism and were not communists themselves. However, not a part of the iron curtain, the Berlin Wall was erected, in 1961, and acted as a reminder of the existence of the iron curtain. The wall itself was constructed from cement, steel, and barbed wire fences reinforced with explosives and traps. The wall was adorned by guard towers regularly positioned with weaponry and machineguns

Gillette Essay Example for Free

Gillette Essay 1. Statement of issues/problems/opportunities (10%): Very briefly describe the organisation‟s situation. Be sure to focus on the underlying issues / problems / opportunities and not symptoms. Do not just reiterate organisational facts. 2. Recommendations (40%): What should the organisation do? Provide a detailed description of the actions necessary for the organisation to deal with the identified problems and opportunities. Be specific enough that a organisation could pick up your recommendations and act on them. 3. Justifications and analysis (50-60%): Provide a set of carefully considered arguments for why your recommendations are likely to be effective. Perform any type of analysis you like on facts obtained in developing your justifications. You can also draw on logic and experiences from materials in other sessions or courses. The bottom line, however, is you must be logical, convincing, and exhaustively thorough. Case Study One: Gillette Gillette stock price is falling from $64 in early 1999 to $24 in 2001. Market share for the profitable disposable razor sector declined about 5 percent while its competitor picked up. The sales declined three percent in 2000. The new CEO James Kilts joined Gillette in February 2001 and realized that the market share of this high profit margin brand is dropping while debt increasing. There are underutilized production capacity which can help the company to save $350 million; management looking at short-term success where they â€Å"stuff† products to distribution channels where the supply is higher than demand and caused aged stocks; to further reduce the relevant cost and solve â€Å"stuck stocks† – he is considering brand advertising and promotions – (something that Gillette seldom do to maintain leadership status). He felt that support for the brand globally got sidelined in the rush for short term results. Better forecast should be impleted to control the budget and costing better based on the market size and targeted market to penetrate. Lower down debt. Assignment questions: 1. To what extent does Gillette rely on incremental innovation or leaps in technology with each product introduction? Gillette may goes after innovation too heavily where the product is technical and sophisticated. Consumers may not understand the complexity and value the high technical functions of the product that sells at a very premium price – X% even more expensive than its preceeders. While it has ignored the value perceived of customers on shavers. The company should consider both factors – internally and externally for strategic marketing. Including political factors, economic factors (rising inflation), company financial situation, as part of the pricing strategy. 2. How successful has Gillette been with its trade-up pricing strategy and its ability to charge premium prices? Very successful. As the number of trade up is high.  However, cost of advertising to existing customers should be much lower than new customers. Priority advertising should be targeted to new market to increase market share, aside from maintaining brand position reinforce the brand in consumers. Message of advertisement is often simple and sharp. However, focus of the ads is very much on product with arg umentative wording, such as â€Å"the best†, â€Å"the only†. The brand may need to focus on brand advertisement for reinforcement purpose and stabilize the market share over the long run. 3. Should Gillette be concerned about the possible cannibalisation of the healthy sales of existing products by each new product launched? Yes. New products should target different market but should not cannibalise existing sales in long run. Different target market, e.g. more premium group where they are early adopters and enjoy premium brands As the company still sells old versions of shavers, it has even more reasons to target different products to different arget group to increase market share. 4. How global and integrated is Gillette‟s global marketing communications? Localised message should be applied to synergy better with other countries as different countries have different cultural background, norms and etc Gillette has a broad coverage strategy in place today and its â€Å"The best a man can get† theme supports this broad coverage strategy. It serves consumers ranging from disposables to high end cartridge systems. Gillette has struggled in the past when it has made attempts to add complementary goods to its offerings. Past attempts at this strategy were subsequently divested. We propose an alternative for phase 3 of the strategy. Rather than adding products that might not carry the value of a strong brand and image we propose that Gillette focus on areas of the world where they don’t have strong market share. Japan is an area specifically mentioned in the case. It is mentioned that Shick has a first mover advantage in Japan. Gillette has a very strong share of the market in the North Atlantic area. It has invested heavily in RD and is getting ready to invest more in advertising and adding plant capacity. Gillette should work to maintain its advantage in the North Atlantic through patent enforcement, new product innovation, and building on customers perceived benefits through advertising and delivery of superior products. Solidifying its leadership position in the North Atlantic, Gillette can then focus on other areas of the world. Rather than allowing Shick to imitate its new Sensor, Gillette can aggressively go after market share in other areas of the world. The marketing campaign will be critical to capturing market share in other areas of the world. Gillette has the opportunity for a first mover play in Japan with Sensor. Marketing campaigns should be tailored to position Gillette uniquely in different parts of the world market. Rather than going for a consistency approach, Gillette should customize the marketing campaigns to either strengthen its leadership position or establish itself as an innovator. The consistency approach to the marketing campaign as outlined in the case does not support this direction. Gillette might even consider launching Sensor in Japan or other parts of the world, followed quickly by a North Atlantic launch. A marketing campaign in Japan promoting first mover status with new technology could help capture increased market share. Gillette has made investments in developing the Sensor system. It now needs to ensure it is capturing appropriate levels of value based on what it can build in the way of perceived benefits to consumers through advertising and superior product. Building this benefit advantage in new and existing markets will allow Gillette to price at a point where it can capture more economic profit than it does today. The investment in plant, equipment, and inventory is a bet that needs to be made for this new product. It will be important for Gillette to be able to deliver enough product to the market and let its competition know that it is dedicated to this production and to protecting its patents. 5. Assess Gillettte‟s approach to women‟s shaving needs? Very manly design as the female designs looks very similar to the male wet shavers. Focuses on technical heavily where it may ignores the demand of consumers – females are different from males during purchase decision and process. Company should penetrate female market, new and large market for the company to yield further profit from the same technology. Focus should be on female buying process and demand, e.g. color, demand, preference, etc. in order to maintain the position of leader in wet shaver market. Both male and female markets can be equally important. However, the company can leverage on the brand equity and value of its success on male wet shaver and hence reduce the cost of advertising – advantage over other products. Penetration of female market should be easier, fast, to enjoy economies of scale at high profit margin ahead of other competitors. Should enhance on product packaging. Overall value to targeted consumers. Psychographic segmentation is concerned with identifying personality traits and distinguishing characteristics in groups of the population. Examples are young and outgoing (for the sale of new forms of music) or grey and conservative (for classical and 60s music). Pyschographic segmentation is clearly relevant to shaving patterns and behaviours. For example, busy well groomed people are likely to go for an upmarket shaving system. In order to fully penetrate market, older versions of the wet shavers – on promotions. To capture middle market and mass market. At an affordable price. Commodity and mass market products. Should achieve both cost advantage differentiation. Didn’t achieve cost advantage because there is underutilized production which may save $350 million According to the product lifecycle, it should allow higher quality at lower price Unit operation cost should go down during growth stage The case points out that Gillette’s competitors were quick to copy new products. Trac II was copied by the competition within five months and other product imitations appeared in 18 and seven months. Historically Gillette did not pursue patent enforcement because of antitrust challenges. This tactic needs to be re-thought. The RD spend needs to be protected to help Gillette retain its competitive advantage and its position as a technology leader. Gillette aggressively patented ideas during the Sensor development. Twenty-two different patents were applied for and obtained by end of 1988. Gillette has access to the patents as an isolating mechanism for building competitive advantage in the market. To protect the investment Gillette has made in the development of the Sensor system, it must leverage the isolating mechanism of the patents. By not pursuing the patents, Gillette maintains market share but does not increase market share. It is allowing consumers of the competitions’ products to stay with that brand versus switching to Gillette’s products. Why would they switch if their brand will be coming with an imitation soon? Image, reputation, and credibility all are important to protecting the superior benefits of an experience good. By not protecting the patents, Gillette is not building the consumer view that it is providing superior products. Protecting the patents will also allow Gillette to further immobilize the resource it has in technology. The equipment and plants are certainly not very mobile, but the people that developed the ideas and technology are very mobile. The patents may offer an advertising or marketing advantage; the 22 patents help Gillette illustrate the innovations they have achieved with Sensor. Though being at the top, Gillette now deals with the problem of product innovation in a somewhat stagnant and mature shaving market and needs to find other ways to remain on top. The possible solutions relate to acquiring its competitors’ business, developing and expanding the women’s market and further reducing the prices to reach more customers.

Language In My Home :: essays research papers

  Ã‚  Ã‚  Ã‚  Ã‚  People say that parents are teachers of good and bad English. People also judge people on how they speak, whether the language is incorrect or just simply inappropriate. I think I had the best of both worlds with my parents.   Ã‚  Ã‚  Ã‚  Ã‚  First of all, my mother is very articulate and has a very large vocabulary. Ever since I can remember she was correcting me on how I spoke and how I wrote. I always would get so mad at her for doing that, but I realize now that my vocabulary and English skills are better than that of many people I associate with. I feel much more confident with my writing and speeches because of my mother’s influence on my grammar. I know I can speak publicly and people will take me seriously and understand what I have to say because of my background in â€Å"good† English.   Ã‚  Ã‚  Ã‚  Ã‚  Secondly, my father is from Jersey City and never graduated college so his way of speaking is different than my mother’s. He speaks more of the vernacular he grew up with and he isn’t worried about what people think when he talks. He says he is more interested in getting his point across than worrying about whether or not people think he is brilliant. My father taught me that in situations of everyday life, you do not have to be articulate all the time. He teaches me everyday that speaking in my own way makes me who I am. He is not instilling upon me to talk â€Å"bad† but different situations call for different languages.   Ã‚  Ã‚  Ã‚  Ã‚  I do feel that my parents encourage me to use correct English whenever I can. They know that with my future plans in life, correct English usage is imperative. They also understand that sometimes I am just going to speak however I want in order to get my point across. I have noticed that even when I have conversations with friends, we all seem to sound so much more intelligent because we are finally using everything we have always been taught to use when speaking. Because of everything I have learned from my parents, I do feel adequately trained in English. I know, depending on my surroundings, how I am suppose to talk and I feel that if I am just hanging outside my house with my friends or giving a presentation to the CEO of a major corporation I can do it.

Psychology spec Essay

We don’t aim to profit from education – we want you to. If you are an existing customer then we thank you for your support. If you are thinking of moving to AQA then we look forward to welcoming you. 1. 2 Why choose Psychology? The revised specification will provide students with a sound understanding of the various methods and approaches in psychology at an introductory level. Knowledge of methods and approaches will be illustrated through various topic areas representing the core areas of social, cognitive, developmental, biological and individual differences. The topic areas have been chosen because of their importance and prominence within the core area and their relevance to everyday life. The specification requires candidates to nderstand ethical issues that must be considered when conducting research in psychology. New content has been introduced, while less popular topics have been removed. Unit 1 of this specification can be delivered as a Short Course. GCSE psychology is no longer tiered; therefore the question papers have been designed to be accessible to candidates of all abilities. . 3 How do I start using this specification? Already using the existing AQA Psychology specification? Register to receive further information, such as mark schemes, past question papers, details of teacher support meetings, etc, at http://www. qa. org. uk/rn/askaqa. php Information will be available electronically or in print, for your convenience. Tell us that you intend to enter candidates. Then we can make sure that you receive all the material you need for the examinations. You can let us know by completing the appropriate Intention to Enter and Estimated Entry forms. We will send copies to your Exams Officer and they are also available on our website (http://www. aqa. org. uk/admin/p_entries. php). Not using the AQA specification currently? Almost all centres in England and Wales use AQA or have used AQA in the past and are approved AQA centres. A small minority are not. If your centre is new to AQA, please contact our centre approval team at centreapproval@aqa. org. uk 1. 4 How can I find out more? Teacher Support You have 24-hour access to useful information and answers to the most commonly-asked questions at Details of the full range of current Teacher Support and CPD courses are available on our web site at http://web. aqa. org. uk/qual/cpd/index. php If the answer to your question is not available, you can submit a query for our team. Our target response time is one day. There is also a link to our fast and convenient online ooking system for all of our courses at http://coursesandevents. aqa. org. k/training 2 Specification at a Glance (Short Course) 4181 Unit 1: aking Sense of other people (41801) Written Paper – 1 hour 30 mins 80 marks – 100% Candidates answer all questions (Full Course) 4182 Other People 80 marks – Unit 2: Understanding Other people (41802) plus For assessments and subject awards after June 2013 there is a requirement that 100% of the assessment is terminal. 3 Subject Content Students should have experience of designing and conducti ng informal classroom research using a variety of methods. They will be expected to analyse data collected in investigations at a descriptive level and draw conclusions based on research findings. They will be required to draw on these experiences to answer questions in the examination for these units. In the delivery of these units, it is expected that teachers will seek out contemporary examples of theories and research to develop their candidates’ understanding of the subject content. 3. 1 Unit 1 Making Sense of Other People Memory Processes of encoding, storage and retrieval. The multi-store, reconstructive and levels of processing explanations of memory. Description and evaluation of studies to investigate explanations of memory. Explanations and studies of forgetting including interference, context and brain damage (retrograde and anterograde amnesia). Eyewitness testimony. description and evaluation ot studies ot tactors which attect the reliability eyewitnesses’ accounts of people and incidents, including the research by Loftus (1974), Bruce and Young (1998). Contemporary practical applications derived from the explanations of memory and forgetting and their benefits and drawbacks.