Innocence and experience Essay Example for Free

Innocence and experience Essay When the theme of innocence and experience is being discussed you can distinguish the correlation between them, ho they both tie into one another. People view childhood as a time of innocence, growth, and freedom from the responsibilities of maturity, whereas adulthood is a time of experience. This coming of age is actually a time where we re-evaluate our identity as adolescences. It is the time in our lives where we continue to find our true selves and explore who we are by experiencing rough circumstances in life-even if it becomes a painful process-while being subjected to an awakening of a bigger picture of life outside our small world. In Araby by James Joyce, we can visualize the transition from fantasy to reality. The narrator thinks of an entire event in the form of an epic quest. He puts Mangan’s sister up on a pedestal and makes himself think he is a knight going after the princess. After hearing the conversation at the bazaar, the narrator reaches an epiphany but not a positive one. Instead of reaffirming his love for Mangan’s sister, he gives up. The boy has his epiphany, but we never find out what happens to his plans or ambitions after the epiphany. Araby focuses on the sudden transition from the illusions of childhood to the insight of maturity. He also leaves out the character’s names to show they haven’t developed a mature identity yet. The boy in Araby experiences the disillusionment in his ideas. At some point in our lives we experience something that begins to diminish what is left of our innocence. But this loss of innocence is what helps us move to a greater wisdom about ourselves and the world around us.

Optical Properties of Zinc Oxide Thin Films Using Two Dopant

Optical Properties of Zinc Oxide Thin Films Using Two Dopant G T Yusuf, MA Raimi, O.E Alaje  and AK Kazeem Abstract The undoped ZnO, Al doped ZnO and Mg doped ZnO films were deposited by a sol-gel spin coating method onto the glass substrates. 0.3M solution of zinc acetate dehydrates diluted in methanol and deionized water (3:1) was prepared. Equal quantity of Aluminum chloride and tin chloride were added to each solution to serve as dopants. The effect of Aluminum and Magnesium doping on the optical ZnO films was studied. The transparency properties of all thin films are more than 80 % at a visible wavelength of (300-800 nm). The optical band gap of pure ZnO thin film is 3.12ev while the band gap for Al-doped ZnO and Mg-doped films are 3.16eV and 3.26eV respectively. All film parameters changed with dopant types. The variation of optical band gap with doping is well described by Burstein–Moss effect. Keywords: Band gap; Doping; Films; Transmittance. Introduction In this Zinc oxide is an II-VI n-type semiconductor with band gap of approximately 3.3 eV at room temperature and a hexagonal wurtzite structure [1]. Recently, doped zinc oxide thin films have been widely studied for their application as conducting electrode materials in flat-panel displays or solar devices. Unlike the more commonly used indium tin oxide (ITO), zinc oxide is a non-toxic and inexpensive material [1]. Furthermore, pure zinc oxide films are highly transparent in the visible range (light wavelength of 400-700 nm) and have high electrical conductivity. However, non-stoichiometric or impurity (Group III elements or Group IV elements) doped zinc oxide films have electrical conductivities as well as high optical transparent. Non-stoichiometric zinc oxide films have unstable electrical properties at high temperature because the sheet resistance of ZnO thin films increases under either oxygen chemisorptions and desorption [9] or heat treatment in vacuum or in ambient oxygen pressure at 3000C-4000C [27]. Turning to impurity doped ZnO thin films, unlike non-stoichiometric ZnO thin films, impurity doped ZnO thin films possess stable electrical and optical properties. Among the zinc oxide films doped with group II elements such as barium, aluminum, gallium and indium, aluminum-doped zinc oxide (AZO) thin films show the lowest electrical resistivity [11]. Aluminum-doped zinc oxide (AZO) has a low resistivity of 2.4Ãâ€"10-4 ÃŽ © cm [11-13], which is quite similar to that of ITO films, which is about 1.2Ãâ€"10-4 ÃŽ © cm [14-16] and AZO also shows good optical transmission in the visible and near infrared (IR) regions. Thus, AZO films have been used as transparent conducting electrodes in solar cells [16, 8]. In addition to doping with Group III elements, doping ZnO with Group IV elements such as [9, 10] Ge, Sn, Ti, Si is also a good way to obtain low resistivity transparent materials in order to replace ITO because Ge, Ti, Zr could substitute on the Zn atom site. For example, Sn can serve as a doubly ionized donor with the incorporation of SnO2 as a solute in ZnO and, consequently, provide a high electron carrier concentration. It is, therefore, expected that the Sn doped ZnO (SZO) will have a higher electrical conductivity and better field emission properties compared with undoped ZnO [10]. A variety of techniques such as DC or RF magnetron sputtering [2], electron beam evaporation [19,20], pulsed laser deposition [21], spray pyrolysis [22,23], chemical vapor deposition [24] and sol–gel processing [25–34,5] have successfully been developed to prepare zinc oxide thin films. Among them, the sol–gel spin coating method is simpler and cost effective. Traditionally, AZO films prepared by this method follow the non-alkoxide route, using metal salts such as acetates, nitrates or chlorides as precursor and dopant, respectively. In addition, organic solvent, such as methanol [20,21], ethanol [16], isopropanol [14], methoxyethanol [11], ethyl glycol and glycerol [10] are widely employed by introducing monoethanolamine (MEA), diethanolamine (DEA) or tetramethyl ammonium hydroxide (TMAH) as stabilizer [10,11,30]. Recently, few studies had reported on the growth of the ZnO thin films with different dopants using sol gel spin coating technique. Therefore, the aim of this research works however is to study the optical and electrical properties of zinc oxide thin films using different dopants with locally fabricated sol gel spin coating technique. Experimental The films have been deposited onto the glass substrates at 400  °C substrate temperature. 0.3M solution of zinc acetate dehydrates diluted in methanol and deionized water (3:1) were prepared and divided into three portions. Aluminum chloride and tin chloride were added to each solution as dopants. A few drops of acetic acid were added to improve the clarity of solution. The concentration of dopants (aluminum chloride AlCl3 ·6H2O, magnesium nitrate hexahydrate [Mg (NO3)2.6H2O and was 3% and kept constant for all experiments. The starting solutions were mixed thoroughly with magnetic stirrer and filtered by WHATMAN filter paper. The solutions were then spin coated on glass substrates which have been procleaned with detergent and then in methanol and acetone for 10min each using ELA 110277248E/2510E-MT ultrasonic cleaner and then cleaned with de ionized water and heated on hot plate for 600C. The coating solutions were dropped onto the glass substrate which was rotated at 4000rpm 45 each by using Ws- 400 Bz – 6NPP/AS spin coater. After depositing by spin coating, the films were then dried at 3000C for 15minutes in a furnace to evapourate the solvent and remove organic residuals. The optical and electrical properties of the films at each time were investigated. The films were then inserted into a tube furnace and annealed in air at 7500C for 1 hour each. The optical transmission and reflectance of the films were examined by spectrophotometer ranging from 400 to 1000nm. The transmittance T and reflectance R data was used to calculate absorption coefficients of the AZO films at different wavelengths. The relationship between transmittance T, reflectance R, absorption coefficient, ÃŽ ±, and thickness d of the film is given by equation (1). (1) The absorption coefficient data was used to determine energy band gap, Eg , using equation (2). (2) Where is the photon energy, A is a constant thus, a plot of against is a curve line whose intercept on the energy axis gives the energy gap. The band energy gap of the film was then determined by extrapolating the linear regions on the energy axis. The absorption coefficient,, associated with the strong absorption region of the film was calculated from absorbance A and the film thickness, t, using (3). (3) The extinction coefficient, k, was evaluated from (4) (4) Where the wavelength of the incident radiation and, t is, is the thickness of the film. The crystal phase of the films was determined by X-ray diffraction (XRD). The refractive index of the films was determined from the maxima and minima of the reflectance curve. (5) Where n is the refractive index, d is the film thickness (nm), is the wavelength (nm) of the incident light, and k is the interference order (an odd integer for maxima and even integer for minima). Results The crystal structure of ZnO films was investigated through X-ray diffraction (XRD). The X-ray diffraction spectrum of ZnO, Al-ZnO and Mg-ZnO film annealed at 7500C with prominent reflection planes is shown in figure 1.The peaks in the XRD spectrum correspond to those of the ZnO patterns from the JCPDS data (Powder Diffraction File, Card no: 36-1451) having hexagonal wurtzite structure with lattice constants a=3.24982Ã…, c=5.20661Ã….The presence of prominent peaks shows that the film is polycrystalline in nature. The lattice constants ‘a’ and ‘c’ of the Wurtzite structure of the films were calculated using the relations (6) and (7). a= √à ¢Ã¢â‚¬ ¦Ã¢â‚¬Å".ÃŽ »/sin ÃŽ ¸(6) c= ÃŽ »/sin ÃŽ ¸(7) Figure 2 shows the optical transmittance spectra of ZnO, Al-ZnO and Mg-ZnO thin films in the wavelength range between 300 to 800 nm. The transparency properties of all thin films are more than 80 % at a visible wavelength of (300-800 nm). It is observed that the transmittance varies with dopant types i.e. aluminum and magnesium. The overall spectra shows an emission band with two obvious peaks, where the first peak, the UV peak which also called the emission or near band edge emission contributed to the free exciton recombination [18]. The second broad peak, also known as the green emission corresponds to the recombination of a photon generated hole with an electron in singly ionized [18]. Figure 1: X-ray diffraction patterns for ZnO thin film for aluminum and magnesium dopants The optical absorbance spectrum measured within the wavelength range of 300–800 nm using a Shimadzu Spectrophotometer is shown in figure 3. Figure 2: Optical Transmittance of the films for aluminum and magnesium dopants Approximately, the band gap alteration of the thin film can be deduced from Figure 3. Here, it evidently shows that changes in the absorption edges are in parallel with types of dopant in the thin film. In order to appropriately estimate the optical band gap equation (2) was used. The presence of a single slope in the plot suggests that the films have direct and allowed transition. It is also well known that ZnO is a direct band-gap material [1] and the energy gap (Eg) can thus be estimated by assuming direct transition between conduction band and valance bands. Theory of optical absorption gives the relationship between the absorption coefficients ÃŽ ± and the photon energy hÃŽ ½ for direct allowed transition as shown in (2) The direct band gap determined using this equation when linear portion of the (ÃŽ ±hÃŽ ½)2 against hÃŽ ½ plot is extrapolated to intersect the energy axis at ÃŽ ± = 0. Plot of (ÃŽ ±hÃŽ ½)2 against hÃŽ ½ for undoped, Al-doped ZnO and Mg-doped films are shown in f igure 3. The optical band of pure ZnO is 3.12ev while the band gap for Al-doped ZnO and Mg-doped films are 3.16eV and 3.26eV respectively. The variation of optical band gap with doping is well described by Burstein–Moss effect [2-5]. For AZO films, compared to pure ZnO films, the contribution from Al3+ ions on substitution sites of Zn2+ ions and Al interstitial atoms determines the widening of the band gap caused by increase in carrier concentration. This is the well-known Burstein–Moss effect and is due to the Fermi level moving into the conduction band. Since doping increases the carrier concentration in the conduction band, the optical band-gap energy increases [2]. Enhancement of band gap thus also ensures that doping was successfully carried out in the ZnO thin films. It is further observed in our present work that an increase in band gap occurs in Mg- doped film as compared with ZnO and Al-ZnO thin films. The absorption properties of the films in UV range are due to the behaviour of ZnO intrinsic optical band gap energy. An absorption coefficient in the UV region significantly varies with types of dopant used. The result suggests improvement in the optical absorption in the UV region with nature of dopant, which provides useful information especially in the optoelectronic devices and device fabrication. . Figure 3: Plot of (ÃŽ ±hÃŽ ½)2 vs. photon energy (in eV) for aluminum and magnesium as dopants Conclusions Transparent conducting thin films (ZnO, Al-ZnO and Mg-ZnO) have been deposited by sol–gel spin coating technique. The optical properties of these films were systematically investigated. X-ray diffraction analysis shows that The peaks in the XRD spectrum correspond to those of the ZnO, Al-ZnO and Mg-ZnO structural patterns is that of hexagonal wurtzite structure with lattice constants a=3.24982Ã…, c=5.20661Ã…. The optical transmittance spectra in the wavelength range between 300 to 800 nm shows that all thin films are more than 80 % at a visible wavelength of (300-800 nm). It is observed that the transmittance varies with dopant types i.e. aluminum and magnesium. The optical band of pure ZnO is 3.12ev while the band gap for Al-doped ZnO and Mg-doped films are 3.16eV and 3.26eV respectively. The variation of optical band gap with doping is well described by Burstein–Moss effect. References [1] N Choudhury and B K Sarma, Bull. Matter. Sci. 32, 43 (2000) [2] E Burstein, Phys. Rev. 93, 632 (1954). [3] T S Moss, Proc. Phys. Soc. London B67, 775 (1954). [4] B E Sernelius, K F Berggren, Z C Jin, I Hamberg and C Granqvist, Phys. Rev. B37, 10244 (19 88). [5] R Cebulla, R Wendt and K Ellmer, J. Appl. Phys. 83, 1087 (1998). [6] B C Mohanty, Y H Jo, D H Yeon, I J Choi and Y S Cho, Appl. Phys. Lett. 95, 62103 (2009). [7] S Gota, J R R Barrado, M Sanchez, N T Barrett, J Avila and M Sacchi, Appl. Phys. Lett. 86,042104 (2005). [8] W Tang and D C Cameron, Thin Solid Films 238, 83 326 (1994). [9] Gà ¶pel, W. and U. Lampe, Influence of defects on the electronic structure of zinc oxide surfaces. Physical Review B, 22(12): 1980p. 6447. [10] Minami, T., H. Nanto, and S. Takata, Highly Conductive and Transparent Aluminum Doped Zinc Oxide Thin Films Prepared by RF Magnetron Sputtering. Japanese Journal of Applied Physics. 23(Part 2, No. 1): p. L280. [11] Igasaki, Y. and H. Saito, The effects of deposition rate on the structural and electrical Properties of ZnO: Al films deposited on (112à ¢Ã¢â€š ¬Ã‚ bar 0) oriented sapphire substrates. Journal of Applied Physics, 1991. 70(7): p. 3613à ¢Ã¢â€š ¬Ã‚ 3619. [12] Minami, T., et al.., Group III Impurity Doped Zinc Oxide Thin Films Prepared by RF Magnetron Sputtering. Japanese Journal of Applied Physics. 24(Part 2, No. 10): p. L781. [13] Kim, H., et al.., Effect of aluminum doping on zinc oxide thin films grown by pulsed laser Deposition for organic lightà ¢Ã¢â€š ¬Ã‚ emitting devices. Thin Solid Films, 2000. 377à ¢Ã¢â€š ¬Ã‚ 378: p. 798à ¢Ã¢â€š ¬Ã‚ 802. [14] Kim, H., et al.., Indium tin oxide thin films for organic lightà ¢Ã¢â€š ¬Ã‚ emitting devices. Applied Physics Letters, 1999. 74(23): p. 3444à ¢Ã¢â€š ¬Ã‚ 3446. [15] Kim, H., et al.., Electrical, optical, and structural properties of indiumà ¢Ã¢â€š ¬Ã‚ Ãƒ ¢Ã¢â€š ¬Ã‚ tinà ¢Ã¢â€š ¬Ã‚ Ãƒ ¢Ã¢â€š ¬Ã‚ oxide thin films for organic lightà ¢Ã¢â€š ¬Ã‚ emitting devices. Journal of Applied Physics, 1999. 86(11): p. 6451à ¢Ã¢â€š ¬Ã‚ 6461. [16] Kim, H., et al.., Electrical and optical properties of indium tin oxide thin films grown by pulsed laser deposition. Applied Physics A: Materials Science Processing, 1999. 69(7). [17] Y E Lee, Y J Kim and H J Kim, J. Mater. Res. 13, 1260 (1998) [18] W.T. Yen, Y.C. Lin, P.C. Yao, J.H. Ke, Y.L. Chen, Thin Solid Films 518 (2010) 3882. [19] T. Minami, H. Nanto, S. Takata, Jpn. J. Appl. Sci. 23 (1984) L280. [20] D.R. Sahu, S.Y. Lin, J.L. Huang, Appl. Surf. Sci. 253 (2007) 4886. [21] H. Kim, A. Pique, J.S. Horwitz, H. Murata, Z.H. Kafafi, C.M. Gilmore, D.B. Chrisey, Thin Solid Films 377–378 (2009) 798. [22] M.A. Kaid, A. Ashour, Appl. Surf. Sci. 253 (2007) 3029. [23] A.F. Aktaruzzaman, G.L. Sharma, L.K. Malhotra, Thin Solid Films 198 (1991) 647. [24] T. Minami, H. Sonohara, S. Takata, H. Sato, Jpn. J. Appl. Sci. 33 (1994) L743. [25] W. Tang, D.C. Cameron, Thin Solid Films 238 (1994) 83. [26] T. Tsuchiya, T. Emoto, T. Sei, J. Non-Cryst. Solids 178 (1994) 327. [27] M. Ohyama, H. Kozuka, T. Yoko, J. Am. Ceram. Soc. 81 (1998) 1622. [28] A.E. Jimenez-Gonzalez, J.A.S. Urueta, R. Suarez-Parra, J. Cryst. Growth 192 (1998) 430. [29] P. Sagar, M. Kumar, R.M. Mehra, Thin Solid Films 489 (2005) 94. [30] T. Schuler, M.A. Aegerter, Thin Solid Films 351 (1999) 125. [31] S.Y. Kuo, W.C. Chen, F.I. Lai, C.P. Cheng, H.C. Kuo, S.C. Wang, W.F. Hsieh, J. Cryst. Growth 287 (2006) 78. [32] J.H. Lee, K.H. Ko, B.O. Park, J. Cryst. Growth 247 (2003) 119. [33] Y.S. Kim,W.P. Tai, Appl. Surf. Sci. 253 (2007) 4911. [34] V. Musat, B. Teixeira, E. Fortunato, R.C.C. Monteiro, P. Vilarinho, Surf. Coat. Techno 180–181 (2004) 65. 1

Oman Cement Company

Oman Cement Company Oman Cement Company (SAOG) was formed in 1978. Rusayl Cement plant was completed in 1983 with an annual integrated cement production capacity of 624,000 tons, of cement. In 1999 clinkering capacity expanded to a total of 1.2 million tons per year. The second production line came on stream in mid 1998. Presently the company is working on expanding the capacity of plant form 1.26 MTS per year to 1.70 MTS per year by upgrading production line No. 1 and No. 2. The company facilities are: 1- Computerized Manufacturing Oman cement manufacturing process is fully computerized. This avoids major hazards in manufacturing and needs less manpower. 2- Central Laboratory The Quality Control is supported by central laboratory consisting of robotics, X-ray spectrometers, laser particle size analyzers and computerized physical properties testing equipment. 3- Quality Management System and Environmental Management System oman cement Quality Management System is in accordance with the Quality Assurance Procedures of ISO 9001 : 2000 certification. 4- Pollution Control. The Oman cement company produces many types of cement which are: 1- Ordinary Portland Cement: It is type I Portland cement. Its uses are reinforced concrete buildings, bridges and railway structures. The typical compound compositions of this type are: 55% (C3S), 19% (C2S), 10% (C3A), 7% (C4AF), 2.8% MgO, 2.9% (SO3), 1.0% Ignition loss, and 1.0% free CaO. 2- Sulphate Resistant Cement: It is type V, is used where sulfate resistance is important. Its typical compound composition is: 38% (C3S), 43% (C2S), 4% (C3A), 9% (C4AF), 1.9% MgO, 1.8% (SO3), 0.9% Ignition loss, and 0.8% free CaO. 3- Moderate sulphate resistant: It is type II cement. This type of cement can be used in structures of considerable mass, such as large piers, heavy abutments, and heavy retaining walls. Its use will reduce temperature rise especially when the concrete is subject to hot weather. Its typical compounds composition is: 51% (C3S), 24% (C2S), 6% (C3A), 11% (C4AF), 2.9% MgO, 2.5% (SO3), 0.8% Ignition loss, and 1.0% free CaO. 4- Oil Well Cement Oil well cement, used for oil wells grouting, usually made from Portland cement clinker or from blended hydraulic cements. It is used for cementing work in the drilling of oil wells where they are subject to high temperatures and pressures. Its typical compound composition is: MgO: 6.0% SO3: 3.0% Loss On Ignition: 3.0% C3S: 48%-65% C3A: 3.0% Insoluble Residue: 0.75% C4AF+2C3A: 24% Production methods: There are four stages to produce cement that Oman cement using which are: 1- Preparation of the raw material at quarries 2- Heating and cooling to produce clinker 3- Preparation of the cement 4- Cement packing Process description: 1- Preparation material at quarries The raw material contains of limestone (80% of raw material), silica, aluminate and iron ore. The quarries located around the Oman cement plant. At quarries the raw materials are extracted with heavy equipments. Then the limestones are crushed with mobile crushers connected with long conveyer belt to transport them to storage passing the auto lab to analysis the samples with x-ray each two hours. After that the raw material are moved to reservoirs. Then they are moved with conveyor belt to the raw mill to grind the raw materials. Finally the grinding raw materials are moved to mixture reservoirs to get proper mixture before fed them to kiln. 2- Heating and cooling to produce clinker The raw materials are moved to channel, where heat exchange is occurred between these material and the raising hot gases from kiln, then the materials are separated from the gases. After that the material moved to calciner where the limestone is converted to calcium oxide, and then the calcined materials arefed to the kiln where the temperature about 1400 c and then leave from kiln to get clinker. Then the clinker leaves from kiln to air to reduce its temperature to 100 c to be ready to be moved to cement mill. Kiln process 3- Preparation of cement The clinker that came out of the cooler will be transported by the bucket chain conveyor to the silo. The bag filter on the top of the silo is sized for the feeding by the bucket chain conveyor and thermal air expansion in the storage. The clinker extracted from the silo is transported by belt conveyors to the cement proportioning. The gypsum is added to the clinker. Then the proportioned materials are conveyed via belt conveyor to cement grinding. Materials ground by ball mill are transported separator by bucket elevator. The coarse particles separated return to ball mill for regrinding while the fine product is collected by the bag filter behind the separator and then conveyed to cement silo with an air slide and bucket elevator. Cement silos is used to store the cement. Cement mill 4-Cement packing The cement from extraction systems under the cement silo is delivered to the buffer bin by air slide and the bucket elevator and vibrating screen, before being fed into each packer. The bagged cement can be loaded directly or stored in storehouse temporarily. Machinery and Equipments: No. Name function 1 Limestone Crusher used in stone quarry to crush limestone 2 Clay crusher used in stone quarry to crush clay 3 Limestone Stacker Used to move limestone to preblending stockpile 4 Limestone reclaimer Used to take preblended mixture from preblending stockpile 5 Coal and iron ore Crusher Used to crush additive materials 6 Coal and iron ore Stacker Used to move iron ore to conveyor belt then to proportioning station 7 Coal iron ore reclaimer Used for reclaiming all additive materials and coal 8 Raw mill used for raw materials grinding and drying 9 Raw mill fan Used to adjust the mill inlet temperature. 10 Preheater fan used to dry the raw materials 11 Preheater and precalciner Preheater used for preheating and partial decarbonation, and precalciner for calcination 12 Rotary kiln used to raise raw materials to a high temperature 13 Grate cooler Used for quenching 14 Cement mill Used to grind cement 15 Bag filter Used to collect dust 16 Coal mill Used for coal drying 17 Bulk loader for truck Used to load the bulk 18 Cement packer Used to pack cement product Quality control system: The quality control department in the Oman cement company function is to monitor product quality in every stage of production starting with extracting the limestone from the quarry till the stage of cement mills, by taking samples and analysis them. 1- The computer and x-ray analysis: The automation lab consists of robot, x-ray spectrometers, laser particle size analyzer and computerized physical properties. The samples will be taken by an automatic sampler from a point between the raw mill and homogenizing silo and then transported manually to the central auto lab, where it will be semi-automatically prepared and sent to an X-Ray analyzer. The results analyzed will be sent to a proportioning computer. The computer will calculate the ratio of raw materials and send out the set value to constant feeder according to the chemical compositions and raw meal module required. 2- Physical analysis: To test the fineness, soundness, setting time, strength, specific gravity, heat of hydration and loss on ignition of the cement to achieve the American specifications requirement. Maintenance procedure: The department functions are: -Checking all machinery and equipments are work properly. -Scheduling and planning for preventive maintenance, predictive maintenance. Coordinating with all departments for daily problem. Planning, coordinating of preventive and breakdown activities for achieving high plant availability to meet production target. The procedure that the Oman cement follows in case of breakdown, preventive and shutdown maintenance are: 1. Breakdown maintenance In case of any breakdown maintenance in the production department, they give information regarding the breakdown to the maintenance department, and maintenance workers are sent to the production plant to fix machine failures. 2. Preventive maintenance here, a team of maintenance workers is sent directly to the production plants to check out whether there is any failure in the machinery or not. 3. Shutdown maintenance When the plant is shut down the employees in the production department sent a letter to the maintenance department and successive steps are taken by maintenance department to solve the failures. The plant shutdown occurs every 6 month in March and September. The process of operating and monitoring production lines and machines instantly, so they can watch the failure and damage of the machines and equipments to repair them or replace them. Technical management The technical management responsibility is to supervise all the mechanical, electrical things and maintain the various equipments and everything that related to maintenance procedure, and this management divided in many sections: a- The machine section The responsibility of this section is prepare emergency and planning schedule and do it to all the equipments and report it to diagnose the unusual failure and fix it. Inspect the machinery, check with drawings and specifications and rectification. It contacts with store section to provide the required replacement parts and also contacts with other sections to maintain the equipments at the workshop. At the workshop they fix the equipments in emergency conditions, check the equipments if they work properly and routinely, takes care the equipments and help to clean them. b) The machine operation section The responsibility of this section fabricate the replacement parts, make an order outside the company to get new parts, lathe the machine parts the required the workshops. c) The immediate machine maintenance section The responsibility of this section is to check and fix the production lines. d) The electrical section The electricity department is responsible to repair and ensure the continuation of the work of all electrical and electronic equipment and precision instruments on the production line and also supervises contact with other sections to that the electricity working properly.

Charles Darwin Essay examples -- Science Evolution Scientist Biology E

Charles Darwin The famous naturalist Charles Darwin embarked on hundreds of miles of land excursions during the often-told story of the H. M. S. Beagle voyage, and on these trips, the most lasting visual impressions for Darwin are the Cordilleras Mountains, the Fuegian natives, and the Brazilian rainforests. The Beagle’s five-year world circumnavigation from 1831 to 1836 emphasized South America and so it is not so surprising the previously mentioned natural wonders had such important impact on Darwin. Somewhat unexpected, though, is the desolate Patagonia plains of Argentina which made an especially lasting impression on Darwin. While certainly not the only important lasting natural impressions for Darwin from the voyage, the natural wonders mentioned previously are quite note worthy because they show up so prominently in a careful reading of Darwin’s writing. Much has been written about the 19th century Beagle voyage and its scientific developments, but instead the emphasis for this research paper will be a selection of Charles Darwin’s most striking land journeys. This assignment will describe and evaluate the dimensions of the ‘gentleman naturalist’s’ most impressive visual memories resulting from excursions into Brazil, Argentina, and Chile. In doing so, this paper will heavily rely on two sources: The Life and Letters of Charles Darwin and what is popularly known as Darwin’s Beagle Diary. Both of these texts are available on the World Wide Web. Before turning to the content of the previously mentioned sources, some additional background is in order. The Beagle voyages’ main mission was to acquire a set of longitudinal measurements in a circumnavigation of the globe. In additi... ...[13] Ibid., 534. Unknown indirect source. Referred in Journal of Researches as: Shelley, Lines on M. Blanc. I was unable to found a bibliographic reference. [14] Ibid., 534. Bibliography: Darwin, C. Journal of Researches into the Natural History and Geology of the countries visited during the voyage round the world of H.M.S. Beagle. 11th ed., London: John Murray, 1913. Quoted from Web Site – Van Wyhe, John ed., â€Å"The writings of Charles Darwin on the web,† 8 October 2003. (29 December 2003). Darwin, F. ed., The Life and Letters of Charles Darwin. New York: D. Appleton & & Co., 1905. Quoted from Web Site – Van Wyhe, John ed., â€Å"The writings of Charles Darwin on the Web,† 8 October 2003. (29 December 2003).

Colgate-Palmolive :: Oral Hygiene Industry

WS1 CP Paper Colgate-Palmolive has been a leader in household and personal care products. In 1991 the company planned new product launches while planning to venture into new markets (Quelch & Laidler, 2011). The company’s plan worked and now the company offers products from oral hygiene products to dish soap to dog food. This paper will discuss the company’s mission. This paper will also discuss a SWOT analysis which according to Kotler and Keller (2009) is â€Å"the overall evaluation of a business’s strengths, weaknesses, opportunities, and threats.† Mission A mission statement should be clear and thoughtful. A mission statement should also provide employees with a sense of purpose and direction (Kotler & Keller, 2009). According to Colgate (2011) the company’s mission statement is â€Å" to provide Colgate with a significant competitive advantage by reducing total delivered costs, extending technology resources and developing excellence in purchasing, logistics and sourcing processes.† The company has been successful in its mission and accomplishing its goals. Strengths Colgate-Palmolive has been a strong force in the oral hygiene industry. The company has many strengths that have contributed to the company’s success. The company has become a global leader with seventy five percent of sales coming from international operations (Colgate, 2011). The company has built strong brand recognition over the years. According to Sekar and Thomas (2008) â€Å"brand differentiation is now becoming an important tactic for combating competition in the hostile marketplace.† While price is important, brand is also an important influence for consumers (Chain Drug Review, 2010). Another influence is product positioning. Colgate-Palmolive has been successful in positioning their products in stores and displaying more skus than other brands. The company has a focus on new product development and innovation. Products range from oral hygiene products to pet foods. The company sells high margin products that they are able to produce at a low cost to the company (Datamonitor, 2011). Colgate-Palmolive’s financial strategy has helped the company to achieve great success. Weaknesses Although the company has many strengths the company does have some weaknesses. While the company remains the market leader in Ireland (Checkout, 2008), the company has experienced a decrease in sales in other European countries (Datamonitor, 2011). This decrease could be the result of less spending on advertising compared to the company’s competitors (DeSanto, 2010).

The Grapes of Wrath - Questions and Answers :: The Grapes of Wrath John Steinbeck

Grapes Of Wrath: Questions and Answers What are the chief reasons for the mass migration to California? Â   I think that the chief reasons for the mass migration to California where based on a few different reasons. The first reason was because everyone was poor. They didn't have enough money to have the most basic necessities in life. They would even go to such lengths as to steal a neighbors house. No body was happy living in Oklahoma. They all had such hard lives that no one had time to do what they wanted to do. It was farm from sun up to sun down. That is what everyone did, and they didn't even get that much compensation for all the devotion that they put into their work day, after day, after day. If I worked at something for twelve hours a day, and just made hardly enough money to keep living, I would get quite frustrated and not be very happy at all. Â   Another reason that people moved to California was so they could move on to a better place. Living in Oklahoma, really wasn't all that good for the Joad's. They couldn't be very happy at what they had. They where a very proud family and wanted to get away and show everyone that they could do some good in this world for themselves. Â   Who are the members of the Joad family unit that set out for California? Briefly state what happens to each of them. Â   Ma, Pa, Ruth, Winfield, Uncle John, and Rose of Sharron all where in the barn. Rose of Sharron was breast feeding a old man, after her baby died. I think she was doing it for personal pleasures. I don't think that she was sincere about the feeling to prolong the mans life. She was always selfish, and I still think she was at the end. I don't blame Connie for leaving her. Al left with his fiancee named Aggie, to start a new life with her. Tom left to become another Jim Casey. He knew what the power of groups could do, the listed to Jim, and knew that he could make a difference. Grandpa died, of natural causes, and they buried him in a field, tore a page out of the Bible and wrote how he wasn't killed, and he died of natural causes.

Aifs Case Havard Business School Essay

1. What gives rise to the currency exposure at AIFS? 2. What would happen if Archer-Lock and Tabaczynski did not hedge at all? 3. What would happen with a 100% hedge with forwards? A 100% hedge with options? Use the forecast final sales volume of 25,000 and analyze the possible outcomes relative to the ‘zero impact’ scenario described in the case. complete the spreadsheet.. 4. What happens if sales volumes are lower or higher than expected as outlined at the end of the case? 5. What hedging decision would you advocate? ANS 1: American Institute for foreign Study (AIFS) had two divisions. 1. The College division, 2. High School travel division. From the college division the students are sent to different parts of the world for semester long courses. From the second division the high school students as well as their teachers are sent for 1-4 week trips worldwide. More than 50000 students are sent out of the country each year on academic as well as cultural exchange programmes. For these two events AIFS requires different currencies other than American dollars. When AIFS got major percentage of its revenue in American Dollars it has to expend most in Euros and British Pounds. If there will be any exchange rate volatility, there will be currency mismatch. This gives currency exposure at AIFS. Ans-2 If Archer-Lock and Tabaczynski would not hedge at all, they had to face the below three risks. i) Bottom line risk: When there will be an adverse move of the exchange rate, there may be an increase in the cost base. If dollar depreciates, they have to pay more for unit dollar of Euro. ii) Volume Risk: They have to buy foreign currency six months before keeping some predicted value of future sales in mind. If the actual value differs from the predicted one, there may be a chance of loss. iii) Competitive pricing risk: They fix their price through the catalog and once price is fixed it difficult to change the price even if there may be a depreciation of dollars. This may result in a huge loss to their business. Ans-3: Refer excel-sheet :QUES-3† Ans-4: Refer excel sheet: â€Å"4-Sales Volume 30000† and â€Å"4-Sales Volume 10000† Ans-5 According to Tabaczynski, the probability of the times that one gains from how the hedging is done, is same as one may losing by doing so in the long run. Hedging by options is a better way to do so as in adverse situations you will only lose the premium amount you have paid. At the same time the company has not to pay any premium and may be benefitted by using futures, but there is a fear of huge loss that can be avoided by using options. So we will advice AIFS to hedge 50% with options and 50% with futures. In this hedging, the loss from the one type of hedging will be compensated by the other to some extent.