All that you need to know about Colloidal System

All that you need to know about Colloidal System A hetrogenius mixture in which solute particles are larger than molucules or ions but cannot be seen by naked eye is called colloidal solution. (Also, called colloidal dispersion, colloidal suspension.) An intimate mixture of two substances, one of which, called the dispersed phase (or colloid), is uniformly distributed in a finely divided state through the second substance, called the dispersion medium (or dispersing medium). The dispersion medium may be a gas, a liquid, or a solid and the dispersed phase may also be any of these, with the exception of one gas in another. A system of liquid or solid particlescolloidally dispersed in a gas is called an aerosol. A system of solid substance or water-insoluble liquid colloidally dispersed in liquid water is called a hydrosol. There is no sharp line of demarcation between true solutions and colloidal systems or between mere suspensions and colloidal systems. When the particles of the dispersed phase are smaller than about 10-3 ÃŽ ¼m in diameter, the system begins to assume the properties of a true solution; when the particles dispersed are much greater than 1 ÃŽ ¼m, separation of the dispersed phase from the dispersing medium becomes so rapid that the system is best regarded as a suspension. According to the latter criterion, natural clouds in the atmosphere should not be termed aerosols; however, since many cloud forms apparently exhibit characteristics of tr ue colloidal suspensions, this strict physico-chemical definition is often disregarded for purposes of convenient and helpful analogy. Condensation nuclei and many artificial smokes may be regarded as aerosols. The dispersion medium may be a gas, a liquid, or a solid. Smoke is composed of a solid dispersed in gas. Milk is a liquid dispersed in liquid. Pumic stone is a gas dispersed in solids. There are two forms of colloidal syatems. 1. Sol: A system composed of non-viscous colloidal solution is called sol. For example, milk. 2. Gel: A system composed of viscous colloidal solution is called gel. For example butter. The colloidal system can be classified into two general classes on the basis of their affinty for liquids:  · Lyophilic System: The system in which dispersed phase and liquid dispersion medium attaract each other is called lyophilic system.  · Lyophobic System: The system in which the dispersed phase and liquid dispersion phase repel each other is called lyophobic system. Types of Colloidal Dispersions Dispersed phase and dispersion medium can be solid, liquid or gas. Depending upon the state of dispersed phase and dispersion medium, eight different types of colloidal dispersions can exist. Eight Different Types of Colloidal Dispersions are: Foam Solid foam Liquid Aerosol Emulsions Gels Solid Aerosol Sol (Colloidal suspension) Solid sol (Solid suspension) It is important to note that when one gas is mixed with another gas, a homogeneous mixture is formed i.e. gases are completely miscible into each other. Colloidal dispersions are heterogeneous in nature and gas dispersed in another gaseous medium does not form colloidal system. When the dispersion medium is gas, the solution is called Aerosol and when the dispersion medium is liquid, the colloidal dispersion is known as Sol. Sols can further be classified into different types depending upon the liquid used.  · Properties of Colloidal System The colloidal system shows following properties. Adsorption: The tendency of molecules and ions to adhere to the surface of certain solids or liquids is called adsorption. Colloidal particles show a high tendency of adsorption. Thus, colloidal syatem provide a large surface area of adsorption of molecules and ions. Brownian Movements: Robert Brown in1927 observed that colloidal particles show random dancing movements. These movements were named Brownian movements. Tyndall Effect: The colloidal partcles scatter light. Ths is called Tyndall Effect. The path of light appears as a cone. It is known as Tyndall cone. This property helps to detect the presence of colloidal partcles. Precipitation: The additions of an electrolytr remove the electrical double layer present around the colloidal particles. As a result, the dispersed particles of a colloidal suspension will aggregate and precipitate. Electrical Properties: All colloidal particles carry same electric charge. This charge may be positive or negative. There is a adsorption of free ions in the dispersion medium. It produces an eletrical double layer around the colloidal particles. The electric charges on the colloidal particles stablize the colloidal system. Filtration: The colloidal particles cannot pass through a parchment membrance. This property of colloidal dispersions is used to separate them from true solution by a process called dialysis. Phase Reversal: The sol and gel form of colloidal system can be interchanged due to change in certain conditions. Certain lyophilic sols form gel undre certain conditions. For example, aqueous agar sols are cooled. It forms a jelly—like gel. The conversion of a sol to a gel is called gelation. If a gel of gelation or agar is heated, it will convert back to a sol. This process is known as solution. The property of colloidal dispersions is called phase reversal. 8. Surface Charge The most important characteristic of colloidal systems is surface charge on the particles. Keep in mind that a â€Å"particle† is a group of bonded atoms or molecules. Charged particles repel each other, overcoming the tendency to aggregate (the attraction force) and remaining dispersed. Particle size plays a major role in the capacity to bear a charge, and the colloidal size range is set by this capacity. In manufactured systems, the charge can be greatly increased over what might occur natu rally. Within the range, the smaller the particle, the greater the surface and the greater the charge that can be applied in manufacture. Only heterogeneous, highly dispersed colloidal systems, containing the smallest possible particles, have a well-developed surface area. Given a constant voltage applied to the system, particle charge is not automatically increased as the substance is made finer, but total charge in the system will increase. Already coarse particles will tend to fall out even if they have received an electrical charge like the smaller particles, because gravity will have a greater influence than the electrical forces which maintain the dispersion. Metallic particles have a great affinity for each other at the atomic level. They are magnetically attracted to each other and want to bond. But the magnetism of metals does not create an added difficulty of attraction against maintaining a colloidal system because of the superior capacity of metals to hold a charge. Given a constant particle size, the higher the concentration in a solution, the more likely the attraction force will overcome the repelling charge, creating larger masses. At some point, the mass will precipitate out due to gravitation. At lesser concentrations, the attraction force is insufficient for precipitative particle bonding, and groups are light enough that gravitation will not pull them out of solution. This is an ideal colloidal system. Biological Significance of Colloidal Systems 33333333333 Manufacturing Colloids and Systems At least five methods were used to manufacture colloids before 1938, including: (1) Grind, (2) Wave, (3) Liquid, (4) Chemical, (5) Electrical. For medical or health purposes, the FDA now allows both the grind and electrical manufacturing techniques to be used. Of these two methods, however, the electro-colloidal process is generally considered to be far superior. (The chemical method, described below, is restricted to industrial or commercial applications.) With the grind method, the inorganic or organic particles are usually no finer than four one-hundred-thousandths of an inch, or about one micron, which is outside the upper end of the ideal size range by a factor of 10. Such particles may or may not be electrically charged. Even if a charge is present, the size of the particles may be great enough that the repelling forces are unable to overcome the pull of gravity. Thus, particles will tend to settle to the bottom of the solution, and much of the effectiveness of the colloidal sy stem will be lost. While some sols owe their stability to particle size, charge and high dispersion, others employ a mechanical stabilizer added to the medium. Such stabilizers include gelatin, glycoproteins, and starch, among other things, which increase solution viscosity and cause the particles to settle much more slowly. The downside to this is that stabilizers tend to block the effects of the colloids, and the particles will still eventually settle if the solution is allowed to stand long enough. If the inorganic or organic particles are within the size range of 1 to 100 nm and are uniformly charged, no stabilizer is required to maintain suspension indefinitely in deionized water, as long as no disruptive influence intrudes. Thus, the integrity and power of a colloidal system is a factor of the interplay among size, charge, concentration, and interaction between particle and medium. It should be mentioned that shape is also a factor. In recent years, the chemical process has been widely employed to replace the inferior grind method, because it provides a convenient shortcut to the more difficult electro- colloidal process. But it also has drawbacks, one of which is the difficulty in getting the chemicals (acids) back out of the colloidal solution. Consequently, traces of the chemicals are frequently left in solution, which can cause unwanted effects, especially in nutritional/medical applications. After studying the health benefits of various forms of colloidal silver, Dr. Leonard Keene Hirschberg, A.M.M.D. (Johns Hopkins) concluded, â€Å"There are two principal ways of producing metallic colloids, viz., chemical and physical (electrical). The two methods yield widely different results, and from a therapeutic point of view I need only deal with the electric colloid metals, since only these present the necessary homogeneity, minuteness of granules, purity, and stability.† A simple illustration will suggest the immense power potential of a colloidal system. The total surface of a one-inch cube of iron is six square inches. By colloidal chemistry, the cube can be divided into particles having a total surface area in the range of 800,000,000 square inches, all expressing electrical energy. The total surface area of the particles in a quarter teaspoon is greater than that of a football field. The Ultimate Colloid The highest quality colloidal systems are produced by the electro-colloidal method, meaning the inorganic or organic particles and (usually) water have been completely â€Å"colloided.† This is simultaneous dispersion and bonding by a current sent through the combination. This is the only method that will create a true colloidal system by manufacture. Products that are simple mixtures of metal and liquid cannot possess nearly the potential of electrocolloids, and are therefore of questionable value. The proper electrical process allows inorganic or organic particles that are well within the colloidal size range to be drawn off an ingot. Animated by Brownian movement, they are able to remain in suspension in a liquid medium almost indefinitely. (Because many nutrients are best transported through the body in water, the best medium to use for ingested nutritional products is pure, de-ionized water.) All other things being equal, the number of particles varies inversely according to the cube of the size change, so if size is reduced 50 percent, overall number is multiplied by eight. This is a mathematical proof, and is determined by actual count using an electron microscope and by atomic absorption. Obviously, ideal size is element dependent. Size is controlled by frequency, amperage and micro-meshes, among other things. The ultimate colloidal sol contains ultra-fine and ultra-light particles in the range of 0.015-0.005 microns in diameter, and they will remain suspended in de-ionized water without need of any other ingredient. There is no visible accumulation of inorganic or organic particles either in the solution or settled on the bottom. Products that show visible particles in the solution or at the bottom of the container indicate that the particles are either too large or have not received the proper electrical charge. The metallic particles in a sol may vary in concentration, but more is not necessarily better, unless we have correspondingly smaller particles. In fact, the reverse is usually true- less is better, and in essence, less is more, functionally speaking, because as noted earlier, the higher the concentration in a solution, the more likely the attraction force will overcome the repelling charge. But even before this happens, effectiveness is reduced. The highest quality colloid will have a certain maximum number of particles. They will be of the minimum possible size, and ideally no more than a â€Å"handful† of atoms hooked together per molecule of water utilized, and in a negatively charged state. This will prevent further aggregation at that size.

Human Resources and Organizational Effectiveness slp 5 Essay

Human Resources and Organizational Effectiveness slp 5 - Essay Example The company has created different plans and strategies like the Every Day Low Prices, which is a pricing strategy to enable customers to buy goods of great quality at low prices. The company’s basic values of respect for individuals, service to customers and striving for excellence speaks for itself. Wal – Mart has tried to ensure it reaches out to the majority of the American population and the major customer group accounting to almost 23 percent belong to families where the annual income is lesser than $25,000. It was also noted that almost half of the customers of the superstore are blue-collar workers and most of the families are either unemployed or elderly (Featherstone, 2005). The main need of Wal-Mart is for a HR program which will help itself to improve and work towards the goals. The company needs a HR program to ensure complete retention of employees as the training involved and the experience required for the job is high. It is important to understand that the company’s strategy is to provide low cost goods and in turn gain a high share of the market. The company aims at working on the basis of economies of scale. Wal-Mart requires using a few techniques as benchmarking metrics. These include the use of Recruitment cost per employee, workforce capabilities and potential customers. For the success of the human resources of the company, it is essential that the company has a clear view on these details. Also these metrics will provide a base for the company to rightly forecast the needs of the employees as well as the company’s needs to get better and more experienced people. Since the company’s aim is to provide low cost goods to the customers daily, it is essential that the company has strong and well balanced operational costs. Hence this metric will help provide Wal-Mart with a strong ability to keep a constant check on the expenses and will also allow the

Dell Computer Corporation Case Study Example | Topics and Well Written Essays - 2750 words

Dell Computer Corporation - Case Study Example The year 1986 was a memorable year for Michael Dell and his corporation when Dell entered the European market. By the year 1989, Dell acquired sales of $50 millions. The last four quarters earned revenue around $57.9 millions2. Dell always aims to deliver the innovative technology and services. This company sells the maximum number of systems than any other computer company. The main principle of Dell is selling computers directly to the customer. In this way, this company can understand the needs of their customers in a much better way. This direct business model3 eliminates the middlemen and hence reducing the cost and time. The strategies of Dell enable it to offer the best possible systems and services at the most reasonable prices. Dell always launches the latest relevant technology much earlier than its competitors. Dell always has everything to satisfy its customer's needs at the most reasonable price. The direct linking with the customer is the key to success of Dell. The processing time is much better than any other competitors with the use of information system. ... The direct linking with the customer is the key to success of Dell. The processing time is much better than any other competitors with the use of information system. The customers are getting the advantages of one-step shopping system for all products and services. They can directly contact the company with a phone-call or internet and this company is always ready with an instant response. It is clear that Dell will continue to put its efforts in order to drive the inventory down by increasing its velocity up to the most possible rate. 1.2 Expansion Dell formed its largest workforce in the year 1998 by recruiting 16,000 employees in central Texas. 4500 employees were hired for its European unit in Ireland. By that time, Dell was ready with its 5 plants, Malaysia, Ireland and three in Texas. Its sixth plant was in China and seventh in Brazil. At present, dell has around 78,700 employees4 in all units. Chapter 2 Strategies 2.1 Build-to-Order strategy The key strategy of Dell was build-to-order. Customer were free to order their PC's directly to the manufacturing floor of the company where various process like assembling and testing were done before shipping the order to the customer. The time taken by the company to deliver the product was just 4-7 days. Due to this strategy, Dell managed to eliminate the resellers and other middlemen and linked directly to the customer. This profit was returned to the customer in the form of lower costs. Linking directly to the customer

Motivation in Business Assignment Example | Topics and Well Written Essays - 1750 words

Motivation in Business - Assignment Example There are many reasons why it is important to have a highly motivated workforce and all of them have become integral parts of the bottom line, to give something positive for the organization’s performance, especially in a highly competitive environment. In this paper, the author tries to incorporate some reasons why it is important to have a highly motivated workforce in an organization. From the perspective of a business consultant, some important moves in order to increase the motivation of employees and the implementation of these actions are discussed. The importance of motivation Motivation has varying definitions because there are different approaches that could explain it including instinct, drive, arousal, incentive, cognitive, and the hierarchy of needs (Feldman, 2003). At some point, it is more effective to combine all these approaches in order to explain what motivation is all about. For example, an individual’s effort to survive after an accident can be expl ained as an impact of his instinct to survive, then he would seek for medical help from the perspective of drive-reduction, and then his expectation that the doctors could help him can be justified using the cognitive perspective (Feldman, 2003). Applying the concept of motivation at work is important for the organization to tap the maximum potential of its workforce. ...Although, for instance, the lack of creativity may not simply imply a lack of motivation because not all people are creative in nature or has the ability to be creative. Fortunately, employees can be motivated in order to achieve the expected energy, commitment, and creativity. Energy It is important to motivate employees because motivation can actually provide them with the energy they need in order to perform their maximum function. From the point of view of Herzberg’s two-factor theory, employee’s satisfaction at work can significantly provide them with substantially high energy in order to do what they are expected of (French et al., 2008). However, Herzberg just emphasized that employees should have the ability and opportunity prior to motivating them.

Marketing Plan on E-Recycling Essay Example | Topics and Well Written Essays - 3500 words

Marketing Plan on E-Recycling - Essay Example of getting rid of the waste, as well as getting a reusable product in return. Hence recycling is a very powerful tool to use resources that would have probably gone to waste and would have caused a lot of damage. Recycling also plays a major role in reducing the greenhouse effect because when recycling takes place the gas emission is very small as compared to when the goods are produced for the first time, this too is because it takes lesser resources to recycle a good. For example, paper can easily be recycled and reused. ... It refers to recycling the electronic products that are no longer in use for many a reasons like outdated technology or any technical or machinery problem etc. E-recycling is becoming one of the most important area in the field of recycling nowadays as more and more electronic items like computers, cell phones etc are being used by more and more people. These devices are becoming more accessible, more affordable and more popular among people as the buying power of people increases and so does their awareness and interest in such products. Moreover, since the technology is changing much more rapidly than it has ever had, people switch to newer products after very short span of using older ones and dispose the used products off. This factor is also adding to the e-waste. Thus, the need of e-recycling is increasing day-by-day and it is time to take as many steps as possible to help solve this issue in order to help reduce pollution. Some examples of goods that are commonly e-recycled th e world over are electronic circuits and gadgets, computers, cell-phones, batteries and other such items. MARKETING PLAN A Marketing Plan is one of the most important parts of a business plan. A good Marketing Plan is a complete set of decisions, strategies and marketing techniques and tactics that would be necessary in order to market a product, brand, service or a product line in the most effective and efficient manner. It is a list of all the necessary actions needed to achieve one or more marketing objectives. The time period of a marketing plan may stretch from one year up to five years. Although listing down the necessary actions, tactics and techniques is very important while formulating a sound marketing plan, but if a marketing plan lacks relevant and

Language is the Most Important Component of Communication Essay

Language is the Most Important Component of Communication - Essay Example The study of language, known as linguistics, has tried to show how language develops among different communities. This study also tries to understand the factors that contribute to similarities and differences in languages. It is clear from the chapter that language does not only mean the ability to talk. There are many forms of language used by human beings to communicate. Spoken language is the most common among them. Currently, there are about three thousands to six thousands different languages in the world. Linguistic anthropology, a branch of linguistics, majors in the study of structure of language. In this study, anthropologists study patterns of sound, the meaning of words made by these sounds, and how these words are combines to make meaningful sentences. Semantics are also covered in this area. Different people from different locations use different terns to describe similar things and physical phenomena in their environment. However, there are some similarities in some of their classifications for instance relatives. Also another area of concern for anthropologists is the origin of language. There are different models that explain the origin and development of language. For instance, from the behaviorist model, a person acquires and develops language from both negative and positive experiences. In linguistics, specifically historical linguistics, the relationship between different languages is also explored. ... Another field of linguistic anthropology is the study of non-verbal communication. Different communities have different forms of nonverbal communication. However, there are those that are universal. Non-verbal communication uses signs and body language to communicate different messages. This field of linguistics have helped very much especially in the study of sign language which is now being used universally. Yet another modern form of language is coded language which is very specialized. This field is being utilized in the field of science for instance in computers. Question two Language is part of every society’s culture therefore understanding the language of a community helps in understanding of a culture of a society. In studying the similarities, differences and development of languages of different communities, we are able to understand the societies better. For example there are communities that live in different geographic locations but have similar or related langua ges. Through this, we can be able to trace the origin of some communities. In these modern days, globalization has influenced almost all aspects in life language included. By making the world a global village means that there is a need for every person from any part of the world to understand each other. In the early times, communication was the major barrier to globalization. Studies in linguistics made everything easier all over sudden. With development of sign language people could communicate and even do business without necessarily having to talk. Again, development of sign language has helped in communication of people who cannot talk or hear. The study of linguistics is being applied

Cooperation is more important than competition Essay

Cooperation is more important than competition - Essay Example In cooperation, there is the collective role of achieving a goal for the benefit of everyone. Competition in businesses leads to the production of better products and services; however, it may lead to the collapse of one business, leaving the other one in the market. In personal development, cooperation is more preferable. It results in better individuals and better society as a whole. Teamwork is the major bearer of cooperation, in which the productivity of each individual is enhanced. The society today embraces competition, which is problematic, instead of embracing cooperation for positive individual and societal growth. Social conditioning is to blame for high competition in the world today. Schools teach students to compete academically, while in the business world, promotions and salary increments are offered on merit of improvements on performances, which is based on ranks. Big businesses, learning institutions, health care institutions, as well as parents still perpetuate the competition element, disregarding cooperation. None of them realizes the adverse effects competition has on the economy, as well as personal development of individuals. It is quite unfortunate that people are not taught cooperative skills at an early age. This has fostered a culture of competition in the society today. ... Besides, cooperation involves making other people better. This is because while cooperating, talented individuals uplift the less talented individuals. Cooperation in itself is fulfilling and therefore, individuals must adopt it. The skills of cooperation should be imparted in individuals when they are still in their early ages. This way, children grow up into adults who value and embrace cooperation. The process of life is all about relationships and interactions between different people. No man is an island, and therefore, each individual is guaranteed of these interactions. An individual’s life journey starting at their home, school, and workplace is about meeting people and living with them. A student cannot study on their own, an employee too cannot work alone, and neither can a person engage in leisure activities alone. Therefore, if individuals lack cooperation, they will live miserable lives, since they cannot harmoniously co-exist with others. Skills of cooperation mu st be inherent in people in order for them to face different situations life presents to them. Cooperation leads to development of the society. In cooperation, one plus one is larger than two, while in competition, it is a zero-sum game, where one wins, and another loses. A case in point is, if two companies are in a competition, one will definitely lose and maybe fall out of business, while the other remains stronger in the market. If this trend is popular in a country, the number of companies may drop, thus adversely affecting the country’s economy. On the other hand, if two companies decide to cooperate, this results in equal growth of the companies, as they will share improvement ideas. Alternatively, they may merge and form a bigger, stronger company.