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X-ray machines that are designed to recover diamonds from an ore body, are used extensively on diamond mines. These machines are extremely expensive and at present, there are no reliable methods, outside the De Beers Group, of determining if the equipment is performing correctly. The object of this research was to manufacture X-ray translucent X-ray diamond simulants with known fluorescent signals ranging from bright to dim. These X-ray diamond simulants will then be used to evaluate the recovery efficiency of all X-ray machines on any diamond mine. The research successfully accomplished the following: 1) The design and building of optical equipment needed to measure the fluorescent signals produced by diamonds and the diamond simulants. 2) Setting up of equipment needed to manufacture the diamond simulants. 3) Determining the ingredients needed to make a diamond simulant and 4) Determining the recipe for the diamond simulants with different fluorescent signals, for diamonds of different sizes.

In the past decades new interest in diamond and possible applications of diamond has emerged. In this master thesis, optical properties of thin films of diamond were investigated for the possible use as an Internal Reflection Element (IRE) in Attenuated Total Reflection Fourier Infra Red (ATR-FTIR) spectroscopy. First a theoretical study of optical properties was made using Fresnel’s equations. Secondly the ray-tracing software TracePro was tested as a possible tool for further investigations of optical properties in advanced geometries. Finally, experimental measurements were made to compare the simulated result with measured data. Results obtained with TracePro were consistent with the theoretically expected results as to dependence of layer thickness, polarization and wavelength, and TracePro was therefore a possible tool for the investigation of optical properties in thin films. Although no extra information was given from TracePro for this specific geometry, TracePro can be a valuable tool in the investigation of more advanced geometries. The experimental measurements showed the importance of a well-defined layer thickness and also showed a stronger dependence of the underlying coating materials than expected from simulations. Further investigations need to be made to fully understand the dependence of the underlying coating materials SiO2 and Si3N4, particularly regarding different polarization states.

In this study, two sizes of diamond grinding wheels which are the diameter of 3 mm with thickness of 0.2 mm and the diameter of 1 mm with thickness of 0.1 mm are fabricated by a creative composite electroforming method. The pure nickel metal is set as anode. The micro cylindrical bar of tungsten carbide acted as spindle of the micro diamond grinding wheel, which is inserted into the hole of ABS mold and the conducting layer pre-coated on the local surface of ABS mold are set as cathode. The nickel sulfate bath mixing a constant amount of diamond particle is selected as electrolyte bath. At the current density of 2.5 ASD, the nickel-diamond composite layer with a constant thickness is electrodeposited on the ABS mold. When the ABS mold is dissolved by using acetone liquid, then the nickel-diamond composite layer could be used as the micro diamond grinding wheel is obtained. Moreover, in the study, the effects of electroforming method, composition of the electrolyte and current density on the surface quality of nickel-diamond composite layer are investigated. From the experiment results, it can be know that at the current destiny of 2.5 ASD, the covered area of diamond particle in this composite layer is 54.19% using the external hanging pump. And the flatness on the surface of this composite layer electroformed in the nickel sulfamate bath is better than that in nickel sulfate bath.

In this work, argon, hydrogen and methane are used as gas sources and nitrogen is used as the doping source. Microwave plasma chemical vapor deposition and two-steps deposition processes have been applied to grow the nitrogen-doped diamond thin film on n-type (111) silicon substrate. Systematical experiments are performed to study the dependence of grown process on working pressure, temperature, microwave power, DC bias, the duration of growth time and the flow rates of gas mixture of argon, methane and nitrogen. The nitrogen-doped diamond thin films are examined by SEM, XRD, Raman and I-V. Raman spectroscopy is the most efficient tool for analyzes the quality of diamond thin films growth. The results show that a positive DC bias can enhance the doping concentration and the qualities of diamond thin films. Form the analyzing results, nitrogen is doped in the sp2 structural grain boundaries of crystallites. The longer diamond thin film grown is, the crystallites become larger and the grain boundaries become smaller, that leads to the larger resistivity of the thin films.

In this work a plasma torch system has been setup. Using the methane as gas source, carbon atoms were ionized and diamond nanoparticles were synthesized. Argon or nitrogen gas was applied as carrying gas for dilution methane. By means of Field-emission scanning electron microscopy (FE-SEM), X-ray Diffraction (XRD), Raman Scattering, Transmission Electron Microscopy (TEM) and Transmission Electron Diffraction (TED) diamond nanoparticles were characterized. The system is characteristic structured with a MP system interior with an antenna. The microwave was guided in chamber and to the antenna tip, and induced the microwave energy gather on the tip then induces plasma under higher pressure. Expect sample N01 that used nitrogen carrying gas and gas flow rate was 0.6 L/min, the particles all have the size between 25-50nm from the analysis of the morphology of the particles by SEM. The particles size increased along with the carrying gas flow rate as well as the pressure increased. The materials structure has been analyzed by Raman, XRD. The natural diamond structure has been found synthesizing the nanoparticles under the high pressure or the higher catalyst gas flow rate. And as carrying gas effect, nitrogen is better than Argon. The electron beam energy would destroy the structure of diamond nanoparticles during TEM analysis and diamond nanoparticles changed from single crystal to amorphous has been observed by TED analysis.

Among Taiwan small and medium enterprise, there exists a debate about should they create own brand or should they still do under OEM way. Even in IEMAB class in Managing College, National Sun Yat Sen University, we have received many comments from professors of two parties, no mention about the practical way, Taiwan small and medium enterprises they are thinking now. This thesis is using Michael Porter¡¦s ¡§Diamond Theory¡¨, ¡§Competition Advantage¡¨ to analysis Winex CO., Ltd. how they competing in world market and how they entering each country, especially those major market countries, such as Netherlands, Indonesia, China. It may be a long way to create own brand name, especially need to overcome the financial crisis during it, but it is still the best way for any enterprise in Taiwan who want to look for a free future and great dream. The Small and Medium Enterprise Adminostrion,MOEA, Taiwan, in their ¡§Small and medium Enterprise Year¡¦s Paper¡¨ has a lots of analyses and suggestions to Taiwan¡¦s small and medium enterprise. Here is taking this case company to make a further comparison so it might make this thesis to be more practical and useful.

People used to be fiscally conservative and shopping used to be very easily satisfied by the consumers due to its economic malaise. But because of higher income and better living quality these days, People have the tendency of spending more money for a more luxurious services like the old days. As a result, tranditional department stores have changed and improved their ways of dealing with customers by developing new formulaion of hardware and software. And in combination of corporation¡¦s new technology, new ways of shopping method has been formed. They call it the ¡§business community¡¨. This is a study from ¡§diamond model¡¨ by Micheal E.Porter in 1990. He stated that in order to win the market over, you need to find out what consumers and the market are looking for. You need to find out what consumers and the market are looking for. You¡¦ll also have to know who your rivals sre and what elements are required for this project. Of course once you have an idea of it all, you will know much capital you need in order to establish your own business. Survey was taken from three main cities in which are Taipei, Taichung, and Kaoshiong areas in Taiwan. Thirty different stores in the survey were used to see which ones the consumers desire the most. This research has found and shown what are needed in order to improve the sales volume for the tranditional department stores, what tranditional department stores are facing these days, and the roles that are played by the government and the competitors. Especially the government, they hold every right to allow or disallow your business. That makes them the protagonist of it all. Every enterprise has its pros and cons. However, when it comes to increasing their sales volume and development, the government¡¦s participation is strongly suggested in order to give out better ideas and advice.

As the time goes by, the more computers become advance, the more heat they produce. If the heat sink of electronic device is not good enough to remove the heat, the electric circuit can be destroyed due to the overheat. This thesis discusses a possible heat sink making of diamond thin layer. Appling the sputtering, Cu thin film has deposited on CVD diamond film, and applying electroplate coating, the thickness of Cu film has increased to 100 µm. In this work a satisfied coating condition has been found to deposite Cu film on diamond, such as: substrate temperature at 300 ¢J, the RF power at 100 Watt and vapor pressure at 2 mTorr for the RF sputtering of Cu on diamond. Using scratch test and pull-off test the adhesion of Cu on diamond has been analyzed to have an adhesive force of 1.9 kg/cm2.Through the simulation with FEMLAB, the finite element method, heat flux, thermal convection and temperature gradient have been simulated. A best thickness of the diamond thin film has been found to be no more thick than 100 µm for the heat sink device.