Invention that has influenced Modern Society free essay sample

Thanks! Choose one invention or discovery that has significantly influenced modern society. Show either the positive and/or negative Influence of this invention or discovery. Our world has experienced many changes within the last century, and one of the ost influential changes Is the Invention of the cellphone. The cellphone has completely changed the way we communicate, as well as the speed, convenience, and quality of our communication. The cell phone has made communication more convenient than ever before. If we find ourselves in a bind. like maybe our car breaks down. we can simply pick up our cell and call a friend or tow truck. If were on the road. away from a telephone directory, we can call the operator and they can connect us to whoever we want. Along with Improving the convenience of our communication, cell phones have made ommunication move taster and taster. I can call you tell you something, and you can call a friend, and that friend can call another friend all within an incredibly small time frame. We will write a custom essay sample on Invention that has influenced Modern Society or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page News that would have once taken several hours (or days) to travel, now travels within a matter of minutes Because news travels so fast, the result is that everyone Is so much more connected than they were In the past. Cells phones have created a network of human beings, and that network Is a living and vibrant thing. In the past, networks of people were imited, because it took lots of time and effort to spread news. Now, because of the speed and ease of communication, networks are allowed to grow much larger and complex. These three improvements in communication (convenience, speed, and greater Of2 communication. I believe that because communication is so easy nowadays, people take less time to think about what theyre saying. An accurately conveyed message is less valuable, because people take communication for granted. People think that if a mistake is made, it can quickly be fixed with another phone call. This is inefficient! You should always strive to communicated clearly and accurately the very FIRST time. Just because its relatively easy to make another call and fix a miscommunication, doesnt mean its acceptable to do that! Modern society will never be the same as it once was. The invention of the cellphone has changed society by giving the human race the amazing power of communication. We must recognize this power, and the responsibilities that come with it. Indeed, the cell phone is an great invention that has changed the convenience, speed, and efficiency of our modern day communication

Enhance the photocatalytic ability Essay Example

Enhance the photocatalytic ability Essay Example Enhance the photocatalytic ability Essay Enhance the photocatalytic ability Essay Abstraction The purpose of this undertaking is to heighten the photocatalytic ability of TiO2 by integrating an inorganic dye ( Ru ( bpy ) 32+ ) with strong seeable light soaking up belongingss into it. This should promote more hydroxyl groups to organize, get the better ofing one of the major disadvantages of TiO2, its inability to absorb in the seeable part. TiO2 and TiO2-Ru ( bpy ) 32+ were synthesised via the sol gel procedure. The burdens included 0, 0.1, 0.5, 1 and 2 % Ru ( bpy ) 32+ . The samples were calcined to 400, 600 and 800 A ; deg ; C. Characterisation of these samples was carried out utilizing the differential scanning calorimeter, x-ray diffraction, Raman, IR and emanation spectrometry. The DSC reported Ru debasement at 450 A ; deg ; C and showed that the dye was holding no consequence on crystal growing below 500 A ; deg ; C. XRD found that 100 % anatase had formed at both 400 and 600 A ; deg ; C and pure rutile was present at 800 A ; deg ; C. Its highlighted that at 700 A ; deg ; C, the anatase to rutile transmutation was speed uping by the increasing sums of Ru ( bpy ) 32+ being added. At 0, 0.1 and 0.5 % the % rutile nowadays was 11.1, 32.2 and 91.2 % severally. Raman analysis was carried out at two optical maser lines, 514.5 and 785 nanometer. The consequences reported at 514.5 nanometers identified the signifier of TiO2 at each calcination temp, which correlated the XRD consequences. The optical maser line at 785 nanometer was aimed at happening Ru extremums. The trouble here was the high fluorescence belongingss, low burdens and high possibility of combustion of the Ru composite. A extremum at 1360 cm-1 was found, nevertheless there is no literature available about the signifier of Ru ( bpy ) 32+ at these calcination temperatures, intending peak assignment was hard. Poor sample readying meant IR consequences were inconclusive and no information could be obtained from it. Diffuse optical density spectrometry calculated the set spread energy of TiO2 at 400, 600 and 800 A ; deg ; C to be 3.2, 3.2 and 3.0 electron volt severally. These values are consistent with the literature. Emission spectrometry was carried out between two scopes 360-600 nm and 480-800 nanometer to let analysis of both TiO2 and Ru ( bpy ) 32+ severally. The emanation spectrum of TiO2 reported a 22 nm displacement towards the seeable light part when TiO2 by itself and TiO2-2.0 % Ru ( bpy ) 32+ were compared at 600 A ; deg ; C. The technique, clip correlated individual photon numeration was used to measure the effects of temperature and the TiO2 environment on the life-time of the Ru stuff. Unheated Ru ( bpy ) 32+ had a long life-time of 557.8 Ns, which decreased to 1.5 Ns when the sample was heated to 400 A ; deg ; C. This important lessening suggests an aroused province negatron is traveling from the Ru ( bpy ) 32+ to the conductivity set of TiO2, therefore photosensitisation is happening. In look intoing the possibility that the stuffs synthesised may hold environmental redress belongingss, photocatalysis was set up. The sample was kept covered with a blue filter which ensured merely seeable light above 420 nanometers would make the sample. The mention, organic pollutant methylene blue degraded at 0.0001 min-1. The photocatalytic analysis of pure anatase showed a little betterment of 0.0002 min-1 under seeable visible radiation. A important betterment to 0.0015 min-1 in the rate of debasement seen at 0.5 % Ru ( bpy ) 32+ emphasised that at higher burdens more hydroxyl groups are produced doing the TiO2-Ru ( bpy ) 32+ stuffs a good campaigner for environmental redress. At 700 A ; deg ; C the acceleration of the anatase to rutile transmutation with increased concentrations of the dye is important. It shows that the Ru composite at this temperature was holding an consequence on the crystal growing of the nanocrystalline stuff. Besides the betterment in the photocatalytic ability of TiO2 when Ru ( bpy ) 32+ was added is of import as it ensures that the sample is now absorbing seeable visible radiation, doing it to bring forth more hydroxyl groups. Novel Photocatalytic Materials for Self- Cleaning Surfaces, 2010 Chapter 1: Introduction Novel Photocatalytic Materials for Self- Cleaning Surfaces, 2010 1. Introduction 1.1 Photocatalysis Photocatalysis is the soaking up of visible radiation by a stuff which consequences in the formation of hydroxyl groups ( A ; bull ; HO ) . ( 1 ) Depending on how efficient the production of these hydroxyl groups is will find how effectual the composite is in environmental redress. Hydroxyl groups are the most aggressive species generated in H2O with an oxidization valve of 2.80 V. ( 2 ) They attack most organic pollutants found in the atmosphere i.e. NOx and CH4. ( 3 ) This undertaking is based on the photocatalytic ability of TiO2, a semiconducting material with a UV visible radiation soaking up cut off at 390 nanometers. The set construction of a stuff is of import in measuring whether it is a good photocatalyst as it determines the light soaking up wavelength of the compound. Figure 1.1 illustrates this point good. TiO2 is an first-class photocatalyst as it remains stable even when it is photoexcited. ( 2 ) It is the anatase signifier of TiO2 that is best for photocatalysis, with a much stronger cut downing power than rutile as the CB is closer to the negative place. ( 2 ) TiO2 is already a proved success in many commercial merchandises such as ego cleansing glass, ( 4 ) anti fogging ( 5 ) and self cleaning surfaces ( 6 ) in infirmaries. By modifying TiO2 with a composite that has a strong seeable light soaking up it is possible that the photocatalytic ability will be improved. If successful more hydroxyl groups will be produced, therefore more organic pollutants will be degraded under normal seeable visible radiation. 1.2 Titanium dioxide TiO2 is found in nature in three polymorphous signifiers anatase, rutile and brookite. Brookite is rather rare and hard to fix hence the anatase ( 3.2 electron volt ) and rutile ( 3.0 electron volt ) signifiers are most common. ( 5 ) TiO2 has a d0 negatron constellation which explains its white visual aspect and inability to absorb seeable visible radiation. The set spread energy of a semiconducting material is of import as it a ) determines the optical soaking up of the stuff and B ) high spots issues that may originate due to recombination. ( 2 ) It is seen that at 3.0 and 3.2 electron volts TiO2 can merely absorb UV visible radiation. Merely 3-5 % of the solar spectrum making the Earth is UV visible radiation restricting the photocatalytic ability of TiO2 instantly. ( 8 ) Besides the rutile signifier has a disadvantage in that it has a higher recombination rate than that of anatase. Figure 1.2 high spots the ability of TiO2 to partake in environmental redress. The soaking up of a photon of light below 390 nm promotes and negatron from the valency set to the conductivity set go forthing an negatron deficient ( h+ ) at the valency set. An oxidization reaction is promoted here. The excess negatron now present in the conductivity set of TiO2 encourages a decrease reaction. ( 9 ) Ohio groups are being produced at each set and it is the concentration/efficiency in the production of these that will make up ones mind whether environmental redress is an option or non. Unfortunately, the efficiency of TiO2 in hydroxyl extremist production exists merely in the UV part. Therefore unmodified TiO2 has a limited consequence on environmental redress. 1.3 TiO2-Ru ( bpy ) 32+ In the past TiO2 has been modified with Ag, ( 8 ) Fe, ( 10 ) and N. ( 11 ) Each dopant was found to impact some belongings of the nanocrystalline stuff. Seery et al described how TiO2-Ag improved both the photocatalytic public presentation of TiO2 and enhanced its anti bacterial effects. The Ag atoms acted as a trap for the CB negatrons leting the efficiency of hydroxyl extremist production to be increased. ( 8 ) Fe, a group 8 component was found to speed up the anatase to rutile transmutation. and nitrogen doping resulted in an active wavelength scope below 520 nanometers, significant in leting TiO2 to organize hydroxyl groups under seeable visible radiation. This undertaking proposes that modifying TiO2 with an inorganic dye which has a strong seeable light soaking up may excessively help photocatalytic activity in the seeable part. Therefore the complex tris ( 2,2-bipyridyl ) dichloro-ruthenium ( II ) hexahydrate ( 12 ) with an soaking up of 450 nanometer was suggested.8 The construction of the dye is three bidentate bipyridine ligands attached to a Ru metal composite. It is hoped that the rule behind Gratzel s dye sensitised solar cells can be imitated slightly so that dyesensitisation occurs between the TiO2 substrate and the inorganic dye. The dye must absorb seeable visible radiation, promote an negatron to the aroused province and reassign the aroused negatron to the CB of TiO2 where decrease reactions occur, bring forthing hydroxyl groups. Ru ( bpy ) 32+ a d6 metal ion has an intense MLCT which has the possible to advance charge injection processes to the conductivity set of broad set spread semi music directors like TiO2, SnO2 and ZnO. ( 13 ) ( Figure 1.3 ) If successful TiO2-Ru ( bpy ) 32+ can be developed in environmental redress as the more hydroxyl groups produced the more of the organic pollutant that is degraded. In Ireland the chief green house gas is methane. ( 14 ) The pollutant produced mostly in agribusiness has a OH sink. If TiO2-Ru ( bpy ) 32+ proves a success, Ireland s part to green house gases can be significantly decreased by merely fixing pigments integrating the TiO2-Ru ( bpy ) 32+ stuffs. ( Figure 1.4 ) These pigments may so be painted onto the outside of sheds on farms and even onto farm machinery in a command to see a lessening in Ireland s agribusiness methane concentration. A technique similar to this by a company called Pilkington was a immense success where they produced thin movies and coated them onto the sides of glass edifices where they degraded soil etc. ( 6 ) In other words the glass was self maintained. ( Figure 1.5 ) 1.4 Synthesis via colloidal suspension gel procedure A simple wet chemical technique illustrated below in figure 1.6. The method was used by Seery et Al in modifying TiO2 with Ag. ( 8 ) It enables unvarying scattering of atoms in a gel. Acetic acid was used to give the connection molecules strength as it ensures strong adhering between Ti-O. The precursor TTIP enables TiO2 formation and H2O makes it a liquid gel. 1.5 Purposes The overall purpose of this undertaking is to heighten the seeable light activity of TiO2. By adding Ru ( bpy ) 32+ into the semiconducting material, synthesizing it via the sol gel procedure a displacement in photocatalytic activity from the UV to the seeable part is predicted, similar to that seen in N and Ag doped systems. The intent of this is to enable the semiconducting material to breakdown organic pollutants both indoors and out-of-doorss by holding the ability to map under seeable visible radiation. The undertaking has three subdivisions synthesis, word picture and photocatalysis. The synthesis of TiO2 modified with Ru ( bpy ) 32+ was done utilizing the sol-gel procedure. This is a simple, yet effectual technique to integrate the dye into TiO2. Characterizing the prepared TiO2 samples is of import as this is the first effort at utilizing this combination via a sol gel procedure. Techniques such as XRD and Raman will place the nature of TiO2, UV/vis and emanation spectrometry will assist find the set spread energies of the samples and will guarantee that the presence of the other ingredient is non impacting their characteristic emanation values. The photocatalytic ability of the prepared samples must besides be investigated ; and will reflect if the sample s debasement rate has improved under seeable visible radiation. A photocatalysis workstation must be set up to include a 60 W lamp, stirring equipment and a composition board box, the organic pollutant impersonator methylene blue is to be used as it is in stock. A bluish filter is a important add-on as it suf ficiently ensures merely light above 420 nm reaches the sample. TCSPC evaluates by what procedure the organic debasement may happen i.e. if dyesensitisation is happening a decrease in the life-time will happen between modified and unmodified TiO2. If an betterment is found the stuff may be so suggested as a possible campaigner for future environmental redress techniques. Chapter 2: Experimental 2. Experimental 2.1 Materials Titanium ( IV ) isopropoxide ( 97 % ) , acetic acid ( 99.8 % ) and tris ( 2,2bipyridy ) dichloro Ru ( II ) hexahydrate [ Ru ( bpy ) 32+ ] pulverization were all purchased from Sigma Aldrich. Methylene blue was obtained from Gurrs Co. All chemicals used as received. Distilled H2O was used in all phases of synthesis, word picture and photocatalysis. 2.2 Synthesis 2.2.1 Preparation of TiO2 The synthesis was carried out in the fume goon as it contained acetic acid. Acetic acid ( 48 milliliter ) was placed in a big beaker and set stirring. Titanium ( IV ) isopropoxide ( 25 milliliter ) was added into the solution dropwise organizing a thick gel. A glass stirring rod was used to blend the gel until stirring saloon was free to travel once more. Distilled H2O ( 150 milliliter ) was added to the solution dropwise, leting a clear syrupy solution to organize. The solution was left stirring for an hr and placed in an oven overnight at 100 A ; deg ; C. 2.2.2 Preparation of TiO2 Ru ( bpy ) 32+ The synthesis was carried out in the fume goon as it contained acetic acid. Acetic acid ( 48 milliliter ) was placed in a big beaker and set stirring. Pre-weighed Ru ( bpy ) 32+ pulverization ( 0.1, 0.5, 1.0 and 2.0 % ) , table 2.2 was added to acetic acid. Titanium ( IV ) isopropoxide ( 25 milliliter ) was added dropwise to the solution, a thick gel formed. A glass stirring rod was used to blend the gel until stirring saloon was free to travel once more. Distilled H2O ( 150 milliliter ) was added dropwise to the mixture and a reddish-orange syrupy solution formed. After stirring for one hr the solution was placed in an oven overnight at 100 A ; deg ; C. A pulverization formed changing in coloring material from light orange to deep ruddy depending on Ru ( bpy ) 32+ concentration. 2.2.3 Calcination of dried TiO2 samples The pulverizations were calcined in the Carbolite furnace leting temperatures of up to 1200 A ; deg ; C. Approximately 1 g of sample was ground down in a pester and howitzer and placed in a crucible. The melting pots were labelled saying the concentration and coveted calcination temperature of the pulverization and its location in the furnace was besides noted as labelling tended to be removed at these high temperatures. The P button on the furnace was pressed and 5.0 A ; deg ; C / min selected. The button was pressed once more and pl appeared on the screen leting a temperature alteration. The button was held in and palladium selected to put the tally continuance. Calcination of samples occurred by pressing run . Samples calcined at 400, 600, 700 and 800 A ; deg ; C each for 2 H periods. 2.3 Word picture 2.3.1 Differential scanning calorimeter The Rheometric scientific derived function scanning calorimeter must honk twice, bespeaking it is on and working decently. The RSI orchestrator icon on the desktop was clicked on. The icon upload was selected on the left of the screen. When it turned green the drama icon selected. The pressing edit trial the parametric quantities were set as follows, 25 500 A ; deg ; C, raging at 10 A ; deg ; C / min. When the system beeped four times it began coolingto 25 A ; deg ; C and so ramped from at that place. Excel data format was used by salvaging as export under file and salvaging as a txt . Then it could be imported into Excel. A clean mention sample and the land down analyte was placed in two separate DSC holders and inserted into the analysing chamber by raising off the palpebra and taking the two rings underneath. The mention was placed on the right and the analyte on the left. Ringss and palpebra replaced and analysis initiated. Run clip was approx. 42 min and so consequences were exported and imported into Excel plotting heat flow ( mW ) against temperature ( A ; deg ; C ) . 2.3.2 X-ray diffraction The pulverizations were characterised utilizing X-ray diffraction ( XRD ) , the Siemens D 500 X-ray diffractometer with the diffraction angles scanning from 2q = 20 80 A ; deg ; , utilizing a Cu Ka radiation beginning. There are two procedures available to XRD, double sided gluey tape or mix with propanone. For word picture of these samples double sided gluey tape was used. The tape was placed on a glass slide ( glass is formless therefore it will non interfere with the analysis ) . The calcined pulverization was ground down utilizing a pestler and howitzer. The sample was so spread out over the gluey tape. The slide was held up to the visible radiation to guarantee no light incursion was happening. Sample was placed in analysis chamber and set running. All information imported into Excel and plotted strength against 2? . The % anatase to rutile was calculated utilizing equation 2.2 below. Equation 2.2 To cipher % anatase to % rutile in a sample ( 8 ) Wr=11+ 0.8 ( 1A1R ) Wr = fraction rutile, 1A = contemplations of anatase, 1R = contemplations of rutile 2.3.3 IR spectrometry The Perkin-Elmer -spectrum 100 FTIR was used for infrared ( IR ) analysis. All samples were prepared as phonograph record in a 1:10 ratio, sample: KBr. These phonograph records were placed between labelled beds of tissue paper during analysis, cut downing wet consumption. Each phonograph record was placed in the IR holder and inserted into the analysis chamber of the instrument. Under the start icon, spectrum selected. The username and watchword were obtained and entered. A background spectrum obtained utilizing the prepared KBr phonograph record, mention. The scan scope was set, 450 4000 cm-1. The analyte was placed in the analysis chamber and the scan icon was selected. When finished the extremums were labelled utilizing the nomadic precursor on the screen. The consequences were originally saved into pigment by pressing print screen on the keyboard and choosing paste in the pigment plan. Subsequently they were saved as an ASCII file and imported into Excel, plotting % transmission against wavenumber ( cm-1 ) . 2.3.4 Raman spectrometry Raman spectroscopic analysis was carried out on two optical maser lines 514.5 and 785 nanometer because 514.5 nanometers merely detected TiO2 extremums. The S.A. ( Jobin Yvon ) LabRam 1B with an argon ion gave a optical maser wavelength of 514.5 nanometers at 50 mW, and the Horiba Jobin Yvon LabRAM HR 800, provided a optical maser line wavelength of 785 nanometers which aimed to enable Ru ( bpy ) 32+ sensing. The instruments were already calibrated during line alteration therefore analysis commenced instantly. Sample readying included puting a little sum of land pulverization onto a microscope slide while flattening it every bit much as possible with the dorsum of a spatula before puting it under the microscope. System set up by turning the key in the optical maser box at the rear of the instrument to on . A green or violet laser line was observed for 514.5 and 785 nanometer severally. The lab spec icon on the desktop was selected and the parametric quantities were set. The scope was set at 100 4000 cm-1 while temperature was varied. The camera and lamp were switched on and a level country was found and highlighted for optical maser irradiation seting concentrate wheel if necessary. Magnification was 10X. A smooth country highlighted for sample irradiation guaranting equal optical maser incursion. For analysis, both the camera and visible radiation were turned away and the optical maser was switched on. Analysis initiated by pressing the hog icon on the toolbar bill of fare. All informations saved in extra as labspec. [ tsf ] and txt so converted and imported into Excel for coverage, plotting strength against wavenumber ( cm-1 ) . The undermentioned parametric quantities were set, clip 5 s and the optical maser filter varied due to the grade of fluorescence and combustion of the Ru sample was unknown. A technique recommended to place the extent of combustion was enlightening the sample with the optical maser for approx 30 s and so analyzing the sample under the microscope placing burn forms and to what grade. 2.3.5 Diffuse optical density spectrometry The technique desired to find the set spread energy of each sample was diffuse coefficient of reflection spectrometry nevertheless, it was non working hence diffuse optical density substituted it. Analysis was carried out utilizing the Perkin Elmer Lambda 900 UV/VIS/NIR Spectrometer between 400 800 nanometer. None of the TiO2 modified samples gave reportable consequences utilizing this technique. Therefore, emanation spectrometry had to be used alternatively to find the set spread energies. Equation 2.3 below was used to find the set spreads of the pure TiO2 samples. Equation 2.3 Formula to cipher set spread energy ? E=1238.9? 2.3.6 Emission spectrometry The Perkin Elmer LS55B Luminescence Spectrometer was used to find the set spread energies utilizing equation 2.3. Approx 20 milligram of sample was placed in a 10 milliliter volumetric flask and made up to the grade with distilled H2O. All volumetrics were placed in a sonicator for 15 min to guarantee unvarying scattering. Dispersions were each placed in a 4 sided vitreous silica cuvette to undergo luminescence. On the desktop the icon Fn Winlab was selected. From the option list scan mth was clicked. The parametric quantities were set between 360 600 nanometer, ? ex = 330 nanometers analyzing for TiO2 and 480 800 nanometer, ? ex = 450 nanometer for Ru ( bpy ) 32+ analysis. The consequences were imported into Excel, plotting strength versus wavelength ( nm ) . The? soap was highlighted for TiO2 emanation consequences and was used to find the set spread energy of the stuff, equation 2.3. These consequences were besides used in puting the parametric quantities for TCSPC. 2.3.7 Time Correlated Single Photon Counting ( TCSPC ) These emanation values were besides used to help lifetime values of the samples utilizing the clip correlated individual photon numeration spectrometer ( TCSPC ) FL900. The spread samples in 2.3.6 above were re-used to obtain the life-times of the samples. The instruments parametric quantities were set based on the emanation spectrometry consequences, alone to each sample. The extremum count was set at 30,000 and the? ex was 333 nanometer. The ice chest was set at approx -28 A ; deg ; C for the sensing system. Both switches for the power supply were turned on. CD900 Test on the desktop was opened. Then right clicked on Initialise all devices to avoid mistake reports the flag must be to the full closed. The F900 package started. Choose position and nF lamp set-up . The force per unit area in the lamp chamber was checked to be about 0.35-0.50 saloon. Then the visible radiation was switched on. The lamp frequence was set to 40 kilohertz. The electromotive force was approx. 7 V and the lamp sensor had an strength of approx. 3. When ready, pressed use so near . A diffuse milklike solution was inserted as a standardization technique. The excitement and emanation wavelengths were set harmonizing to earlier consequences. Scan started and saved to a file. The life-times of the samples were calculated by opening the saved life clip spectra, pressing informations on the control panel and taking exponential tantrum . There are two alternate adjustment processs ( I ) reconvolution tantrum and ( two ) tail Fit. Tail tantrum was used because these samples were expected to hold longer life-times than the heavy hydrogen lamp ( approx. 1 N ) . The samples were placed in a chamber for analysis. 2.4 Photocatalysis 2.4.1 Photocatalysis of synthesised samples utilizing a 60 W visible radiation bulb The photocatalytic debasement of the organic pollutant impersonator, methylene blue was determined utilizing the Perkin Elmer Lambda 900 UV/VIS/NIR Spectrometer between 400 800 nanometer. Approx. 0.06 g of calcined pulverization was placed in a glass beaker with a stirring saloon where methylene blue ( 50 milliliter, ten 10-5 M ) was added. The sample was placed on a magnetic stirring home base and was covered with a bluish filter, guaranting that merely light above 420 nanometers would make the sample. Equilibration was reached between the sample and the organic pollutant by stirring the suspension in darkness for 30 min. After 30 min a 3 milliliter aliquot was taken and placed in a labelled extractor tubing and was stored off in a dark imperativeness. The bluish filter was replaced over the sample and the 60 W light bulb was switched on. After 30 min, a 3 milliliter aliquot was removed, this procedure was repeated for 2 H and 30 min taking a 3 milliliter aliquot every 30 min while guaranting the bluish filter was replaced each clip. The samples were non cloudy as the pulverization was denser than the methylene bluish solution ; therefore they were nt centrifuged for 8 min like Degussa P25. The debasement of methylene blue was measured utilizing the UV/vis spectrometer. On the desktop Lambda 900 selected. Methylene bluish absorbs at approx. 456 nm hence scan scope set between 500 800 nanometer. Baseline rectification and car nothing were both done. Ordinate manner was set to A ( optical density ) . Choosing the sample icon computing machine requests the figure of samples, ( 5 in this instance, over 2.5 hour ) . computing machine now prompts each sample in order. Consequences saved and imported into Excel plotting optical density against wavelength ( nm ) . A 1st order kinetic secret plan, plotting Ln ( Ao/A ) against clip ( s ) , where A is the optical density at times t and A0 is the optical density at times zero of the consequences, generated. The incline of this line was equal to the rate of debasement and was subbed into equation 2.3. Equation 2.3 To cipher the rate of debasement t=ln2k where K is the photocatalytic rate of debasement of methylene blue by the sample. Methylene blue was prepared from the stock solution ( 10-3M ) in the research lab and was prepared in a 1:100 ratio of methylene blue: deionised H2O giving methylene blue ( 10-5 M ) . Chapter 3: Consequences and Discussion 3. Consequences and Discussion 3.1 Synthesis TiO2 and TiO2 modified with Ru ( bpy ) 32+ at concentrations runing from 0.1 to 2.0 % was prepared via the sol gel procedure and so calcined at 400, 600 and 800 A ; deg ; C. An issue arose environing the readying of TiO2 colloidal suspension gels. The documented experimental stated that acetic acid had to be added to the TTIP which resulted in cloping issues. It was found that by adding TTIP to the acetic acid the synthesis worked better, from here the original experimental was followed. After drying at 100 A ; deg ; C a white and ruddy orange solids were collected, declarative of TiO2 and TiO2-Ru ( bpy ) 32+ . Approximately 3 g of stuff was obtained after drying expect at 2.0 % Ru ( bpy ) 32+ as 1/5 of the declared volume was used in the synthesis to cut down Ru ( bpy ) 32+ ingestion. When calcined the unmodified TiO2 samples remained white going shinier as the temperature increased. The modified TiO2 samples turned gray black with increased burden and temperature. 3.2.1 Differential Scanning Calorimeter DSC analysis was carried out on TiO2, TiO2 modified with Ru ( bpy ) 32+ and untreated Ru ( bpy ) 32+ pulverization. The consequences in figure 3.4 show that in both samples incorporating TiO2, a loss of H2O and acetic acid at 100 A ; deg ; C occurred. A larger H2O extremum was seen for the modified TiO2 sample as it was non to the full dried when analysed. The 330 A ; deg ; C is declarative of the formless to crystalline formation of TiO2. The presence of Ru ( bpy ) 32+ did non impact the crystal growing of TiO2 up to 500 A ; deg ; C as the formless to crystalline stage alteration remained the same in both modified and unmodified TiO2. 3.2.2 X-ray diffraction ( XRD ) XRD analysis was carried out on all samples prepared. This determined what signifier of TiO2 was present at each temperature. The consequences showed that anatase formed at 400 and 600 A ; deg ; C and pure rutile was present at 800 A ; deg ; C for the unmodified TiO2 samples. Figure 3.5 below high spots this. The burdens were presumed to moo to see ruthenium extremums under XRD, nevertheless at TiO2-2 % Ru ( bpy ) 32+ Ru extremums were detected. There was no literatre published on the effects of temperature on Ru ( bpy ) 32+ but on comparing of the extremums, the 2 % lading complement that of the criterion calcined to 600 A ; deg ; C. The signifier at these high temperatures is still unknown. A communications paper found that metallic ruthenium17 signifiers at 600 A ; deg ; C but no farther publication was made on it. Figure 3.5 XRD exemplifying anatase, rutile and Ru extremums found in TiO2 modified with 2 % Ru ( bpy ) 32+ at 600 A ; deg ; C. The significance of this consequence was that all other samples analysed at 600 A ; deg ; C calcination, modified and unmodified were strictly anatase but at this lading rutile extremums were beggining to organize. Baring in head that the anatase to rutile transmutation occurs at 700+ A ; deg ; C, analysis was initated on 0, 0.1 and 0.5 % burdens at 700 A ; deg ; C and 800 A ; deg ; C. As expected all 800 A ; deg ; C samples were 100 % rutile. The samples investigated at 700 A ; deg ; C resulted in an addition in the % rutile nowadays at increased burdens. A similar consequence was seen when TiO2 was doped with Ag and Fe. Ghosh et al highlighted a similar happening in Fe doped TiO2 sample.18 This discovery meant that the presence of Ru ( bpy ) 32+ was impacting crystal growing at 700 A ; deg ; C. A new revalation as the DSC consequences confirmed earlier that the dye was holding no consequence on the crystal growing up to 500 A ; deg ; C. Aceleration in the anatase to rutile transmutation is important as it means that TiO2 is being converted into its most stable signifier, rutile earlier. It is possible that the samples can be tuned to accomplish a peculiar concentration of each TiO2 signifier. Figure 3.6 Shows the important acceleration in crystal growing at 700 A ; deg ; C clearly. 3.2.3 Raman Spectroscopy Samples were analysed under Raman at 514.5 and 785 nanometer. Merely TiO2 extremums were obtained at 514.5 nanometers, most likely due to the low burden of Ru ( bpy ) 32+ in the stuff or that at higher temperatures the composite had decomposed. The Peaks observed at 400 and 600 A ; deg ; C were declarative of anatase, and rutile at 800 A ; deg ; C. These consequences correlated the XRD consequences for the same temperatures. After correspondence with research workers specialised in Ru composites it was agreed that the laser line of 514.5 nanometer was deficient for Ru sensing and that a laser line of 785 nanometers would be more suited. Burning of the sample was suspected which would suppress sensing. Experiment as to what % filter to utilize was carried out by traveling from 100 to 25 to 10 to 1 % . It was found that by cut downing the filter to 1 % the sample was less likely to fire. This determination was made based on exposing the sample to the optical maser at the assorted filters for several seconds, so exchanging back on the microscope to find if the sample had burned or non. The grade to which the dye was firing became cl

The Pequot War - A History

The Pequot War - A History The Pequot War - Background: The 1630s were a period of great unrest along the Connecticut River as various Native American groups battled for political power and control of trade with the English and Dutch. Central to this was an ongoing struggle between the Pequots and the Mohegans. While the former typically sided with the Dutch, who occupied the Hudson Valley, the latter tended to ally with the English in Massachusetts Bay, Plymouth, and Connecticut. As the Pequots worked to expand their reach, they also came into conflict with the Wampanoag and Narragansetts. Tensions Escalate: As the Native American tribes fought internally, the English began to expand their reach in the area and founded settlements at Wethersfield (1634), Saybrook (1635), Windsor (1637), and Hartford (1637). In doing so, they came into conflict with the Pequots and their allies. These began in 1634 when a noted smuggler and slaver, John Stone, and seven of his crew were killed by the Western Niantic for attempting to kidnap several women and in retaliation for the Dutch killing of the Pequot chief Tatobem. Though Massachusetts Bay officials demanded those responsible be turned over, the Pequot chief Sassacus refused. Two years later, on July 20, 1836, trade John Oldham and his crew was attacked while visiting Block Island. In the skirmish, Oldham and several of his crew were killed and their ship looted by Narragansett-allied Native Americans. Though the Narragansetts typically sided with the English, the tribe on Block Island sought to discourage the English from trading with the Pequots. Oldhams death sparked outrage throughout the English colonies. Though Narragansett elders Canonchet and Miantonomo offered reparations for Oldhams death, Governor Henry Vane of Massachusetts Bay, ordered an expedition to Block Island. Fighting Begins: Assembling a force of around 90 men, Captain John Endecott sailed for Block Island. Landing on August 25, Endecott found that most of the islands population had fled or gone into hiding. Burning two villages, his troops carried off crops before re-embarking. Sailing west to Fort Saybrook, he next intended to capture the killers of John Stone. Picking up guides, he moved down the coast to a Pequot village. Meeting with its leaders, he soon concluded they were stalling and ordered his men to attack. Looting the village, they found that most of the inhabitants had departed. Sides Form: With the beginning of hostilities, Sassacus worked to mobilize the other tribes in the region. While the Western Niantic joined him, the Narragansett and Mohegan joined the English and the Eastern Niantic remained neutral. Moving to avenge Endecotts attack, the Pequot laid siege to Fort Saybrook through the fall and winter. In April 1637, a Pequot-allied force struck Wethersfield killing nine and kidnapping two girls. The following month, leaders of the Connecticut towns met in Hartford to begin planning a campaign against the Pequot. Fire at Mystic: At the meeting, a force of 90 militia under Captain John Mason assembled. This was soon augmented by 70 Mohegans led by Uncas. Moving down the river, Mason was reinforced by Captain John Underhill and 20 men at Saybrook. Clearing the Pequots from the area, the combined force sailed east and scouted Pequot Harbors fortified village (near present-day Groton) and Missituck (Mystic). Lacking sufficient forces to attack either, they continued east to Rhode Island and met with the Narragansett leadership. Actively joining the English cause, they provided reinforcements that enlarged the force to around 400 men. Having seen the English sail past, Sassacus wrongly concluded that they were retreating to Boston. As a result, he departed the area with the bulk of his forces to attack Hartford. Concluding the alliance with the Narragansetts, Masons combined force moved overland to strike from the rear. Not believing they could take Pequot Harbor, the army marched against Missituck. Arriving outside the village on May 26, Mason ordered it surrounded. Protected by a palisade, the village contained between 400 to 700 Pequots, many of them women and children. Believing his was conducting a holy war, Mason ordered the village set on fire and anyone trying to escape over the palisade shot. By the end of the fighting only seven Pequots remained to be taken prisoner. Though Sassacus retained the bulk of his warriors, the massive loss of life at Missituck crippled Pequot morale and demonstrated the vulnerability of his villages. Defeated, he sought sanctuary for his people on Long Island but was refused. As a result, Sassacus began leading his people west along the coast in the hope that they could settle near their Dutch allies. Final Actions: In June 1637, Captain Israel Stoughton landed at Pequot Harbor and found the village abandoned. Moving west in pursuit, he was joined by Mason at Fort Saybrook. Aided by Uncas Mohegans, the English force caught up to Sassacus near the Mattabesic village of Sasqua (near present-day Fairfield, CT). Negotiations ensued on July 13 and resulted in the peaceful capture of the Pequot women, children, and elderly. Having taken refuge in a swamp, Sassacus elected to fight with around 100 of his men. In the resulting Great Swamp Fight, the English and Mohegans killed around 20 though Sassacus escaped. Aftermath of the Pequot War: Seeking aid from the Mohawks, Sassacus and his remaining warriors were immediately killed upon arriving. Desiring to bolster goodwill with the English, the Mohawks sent Sassacus scalp to Hartford as an offering of peace and friendship. With the elimination of the Pequots, the English, Narragansetts, and Mohegans met at Hartford in September 1638 to distribute the captured lands and prisoners. The resulting Treaty of Hartford, signed on September 21, 1638, ended the conflict and resolved its issues. The English victory in the Pequot War effectively removed Native American opposition to the further settlement of Connecticut. Scared by the European total war approach to military conflicts, no Native American tribes sought to challenge English expansion until the outbreak of King Philips War in 1675. The conflict also laid the foundation for the perception of future conflicts with the Native Americans as battles between civilization/light and savagery/darkness. This historical myth, which persisted for centuries, first found its full expression in the years after the Pequot War. Selected Sources Society of Colonial Wars: The Pequot War Mystic Voices: The Story of the Pequot War

Motivation theories for drug use and addiction Research Paper

Motivation theories for drug use and addiction - Research Paper Example These early views on the reasons for continued drug use have been replaced by recent research which have contrasting perspectives that suggest that negative reinforcement is not a strong influence on drug motivation. Thesis Statement: The purpose of this paper is to investigate the motivation theories for drug/ alcohol use and addiction. Motivations for Drug Use Contemporary theory of the motivation for drug addiction makes paradoxical claims about the psychological basis for seeking drugs. Drug-seeking is considered to result from subjective craving for the positive effects of the drug, which suggests that this behavior is intentional. On the other hand, a key factor in the clinical diagnosis of drug dependence is that drug-seeking is resistant to the intention to quit, which means that drug-seeking is habitual or automatic. This is paradoxical, because drug seeking cannot be concurrently intentional and automatic (Hogarth & Chase, 2011). There are several reasons for people to take drugs. These include â€Å"peer pressure, relief of stress, to have increased energy, to relax, to relieve pain, to escape reality, to feel more self-esteem, and for recreation† (Columbia Encyclopedia, 2009, p.14591). Individuals resort to taking stimulants to keep alert, or cocaine for the feeling of excitement it produces. Similarly, athletes and bodybuilders may take anabolic steroids to increase muscle mass. There are numerous stressors which increase the risk of alcohol use disorders in humans. In alcohol and other drug dependent (AOD) people, drug craving is increased by internal and external forms of stress, which can also trigger relapse (Wand, 2008). Stress is generally defined as â€Å"any stimulus that challenges physiological homeostasis – that is, which alters the balance or equilibrium of the normal physiological state of the organism† (Wand, 2008, p.119). However, various forms of stress have different physiological consequences, stimulating different combinations of signaling molecules. These molecules aid in cell-to-cell communication, such as neurohormones, and produce distinctive outcomes on physiological processes. Therefore, the type and duration of stress have to be specified, for planning the treatment. Further, individuals respond differently to a particular type of stress, â€Å"and physiological and behavioral responses tend to be associated with dis tinct coping styles† (Wand, 2008, p.120). An interaction of environmental and genetic factors play a part in both susceptibility to alcohol and other drugs (AOD) use disorders, and in people’s responses to stress. Prenatal and early life stress can have impacts on the body systems involved in the stress response, for the entire life span, thereby predisposing an individual to certain diseases. This early programming effect is partly affected by â€Å"epigenetic mechanisms that alter heritable traits without manifesting as changes in the DNA sequence, and which also can aid in the development of AOD disorders† (Wand, 2008, p.120). Motivation Theories for the Use and Addiction to Drugs and Alcohol An Affective Processing Model of Negative Reinforcement Baker, Piper and McCarthy (2004) reformulate the negative reinforcement model of drug addiction. They propose that the escape and avoidance of negative affect is the prepotent motive for

Paul is an Artist of International Fame Essay Example | Topics and Well Written Essays - 750 words - 7

Paul is an Artist of International Fame - Essay Example He will be with us in Houston, for two days. The conference venue is at Richmond.† On the conclusion of the first day of the seminar, at my insistence, Paul uncle gives a brief introduction about his art. â€Å"The sponsoring UNO agency has made all the arrangements for my boarding and lodging. I dislike the ambiance of staying in a 5 Star hotel. I eat simple home food. I live with my three children and we have an ancestral house in a two-acre plot in the suburbs of Port-au-Prince.† â€Å"My children are married, and we live as a joint family. My two sons are not interested in this vocation and the eldest one takes a limited interest in this art which is full of intricacies.† But in general, Paul gives lots of information on the copper-art and the present condition of art in Haiti. â€Å"Many traditional art-forms of Haiti are dying a slow death with no appreciation of genuine art and lack-luster approach of the Government authorities. Materialistic civilization has impacted life in all the segments of life. People have lost love for art. By pursuing this as art as a vocation, it is difficult to eke out a living†¦.my children are right perhaps to pursue alternative careers, where there is money. My second son has already migrated to Australia. † I visit him after 5 years. His house is on a hillock in the distant suburbs of Haiti. He has problems in recognizing me but with the mention of â€Å"Houston,† he embraces me. We speak a lot about Haiti art and his copper plates and pitchers in particular. He shows some of his centuries-old family collections of pitchers. When I tell him that â€Å"Traditional Art of Haiti† is one of the subjects that I teach at the college level, he is greatly fascinated.   

Models of Organized Crime Executive Summary Essay Example for Free

Models of Organized Crime Executive Summary Essay The difference between the patron-client and bureaucratic model is based on who is appointed the leader. The organization is based on trust and loyalty similar to the family. The main role as a patron-client is to show leadership by providing financial assistance and safety for the client. The client returns the favor by acting out different duties coming from the patron. The patron-client has the advantage because they are the sole providers for all communication for the client. Income is providing from executing from murders, thefts, frauds and drug trafficking. The patron client dominates a particular location for his organization. The group is also connected with police officers who are specialized in criminal operatives. The bureaucratic model is more focus on setting goals. Bureaucratic have a higher clientele but are selective with who is inducted into their group. All orders come from the boss in order to execute the next chain of events. The most important operation in the business is hierarchy. In order for the plan to be successful, all members must fully understand their role. This process is crucial for the structure to the organization and the members. The members must be able to carry out the task. If a step was missed by a member, they will eliminate from the project. The organization cannot afford for their hard work to be flush down the drain because an associate could not be trusted. Weber’s and Taylor’s models of the bureaucratic theory are most effective when used for larger events. Once a plan is started the bureaucratic should be introduced in order to control all lines of communication and any rules that were initially set. The patron-client is more decentralized and does not require control over unit members. Parton-clients are more favorable in social networks because there not fully involved with the plan. Bureaucratic model are vulnerable to cops  because upper management is stricter. The patron-client provides information for the job. For instance, the investigator will provide the client information so the whereabouts will not be an issue making the job easier to perform. In conclusion, each model has its expression of criminal cooperation with different socioeconomic conditions and law enforcement strategies to avoid media attention. Crime groups are broken down into different characteristics. Members of organized crime groups normally attack public officials and law enforcement agents. . Understanding organized crime is important because it gives the government the ability to know how they work so can be bought to a stop. References Connor, O. (2012). Organized Crime Investigation. Retrieved from http:// http://www.drtomoconnor.com/3220lect07a.htm/ Mallory, S. (2007). Understanding Organized Crime. Sudbury, MA: Jones and Bartlett Publishers

death penalty :: essays research papers

When turning on the television, radio, or simply opening the local newspaper, one is bombarded with news of arrests, murders, homicides, and other such tragedies. There are many things that I don't agree with in today's society but, out of all the wrongdoing that takes place, I believe murder including the death penalty is the worst of them. I am strongly against the death penalty because it violates God's rules, costs the tax payers too much money, the possible "wrongly accused," and it is cruel and unusual punishment. How often do these concepts creep into the public's mind when it hears of our `fair, trusty' government taking away someone's breathing rights? I do not support having the death penalty because it violates religious beliefs. Many religions, such as my own, Catholicism, follow the rules that God sent to use through the Ten Commandments. One of the most important of those ten states, "Thou shall not kill." If you are executing an individual, that clearly violates this commandment. Murdering any person, no matter what the individual has been convicted of, is a mortal sin. Therefore, God will punish anyone who aids in executing people. I believe that religious beliefs, such as the Ten Commandments, are the corner stone for our law system. Executing someone should not be made an exception to God's rule. My next reason against the death penalty is that taxpayers waste too much of their money with the death penalty. The average death penalty case is appealed three times. This means that the taxpayers must pay for the same trial to be heard three times. This is a very expensive practice. Also, the average convicted murder spends 12 years on death row. If supporters of the death penalty are positive enough to kill the person for committing the crime, shouldn't the supporters be confident enough to execute them in a timely manner? Why spend the taxpayer's money keeping these inmates in jail for so long? Taxpayer's money should go to better society, not to accommodate the prisoners that are going to end up dead. There's always the chance of the innocent being in the wrong place at the wrong time.