نتایج جستجو برای: diamond
تعداد نتایج: 20974 فیلتر نتایج به سال:
عنصر کربن شامل آلوتروپ های گرافیت، الماس و کرباین است. اخیراً در آزمایش های مختلفی ساختاری بلوری از عنصر کربن مشاهده شده که با دیگر ساختارهای کربنی متفاوت است. در مورد نوع ساختار این فاز جدید کربنی که n-diamond نامیده شده اتفاق نظر وجود ندارد. اولین بار ژارکوف و پالاتنیک پیشنهاد کردند که این فاز، یک ساختار fcc از کربن است. از آنجایی که ساختار n-diamond یک ساختار فراپایدار است، موریتا و همکارانش ...
اخیراً در آزمایشات مختلفی، ساختاری بلوری از عنصر کربن مشاهده شده که با دیگر ساختارهای کربنی، یعنی الماس، گرافیت و فولرین بسیار متفاوت است. این فاز کربنی n-diamond نامیده می شود. اگرچه بسیاری از بازتاب ها در الگوی پراش x آن، مشابه بازتاب ها در الماس است، اما پراش الکترونی این فاز، همچنین شامل بازتاب هایی قوی در (200)، (222) و (420) است که برای الماس ممنوع می باشد. در مورد نوع ساختار بلوری آن اتفا...
Two types of micron-diamond films were prepared on YG6 substrate by hot filament chemical vapor deposition(HFCVD) method. Morphology and orientation of crystalline growth were evaluated by SEM and XRD. Diamond film coated tools and sapphire wafer’ surface before and after lapping experiment were contrasted. The results indicated that a significant change in Raman spectrum of two types of micro...
This paper reviews existing studies and investigates thermal operational regimes of diamond bit during drilling operations. The operating temperature of the diamond core drill is studied under bench condition and an optimal thermal range are presented. Based on this study, it was noted that glazing of diamond tools is observed at temperatures less than 327°C, and normal wear of diamond tools is...
Evaluation and prediction of performance of diamond wire saw is one of the most important factors involved in planning the dimension stone quarries. The wear rate of diamond wire saw can be investigated as a major criterion to evaluate its performance. The wear rate of diamond wire saw depends upon non-controlled parameters related to rock characteristics and controlled parameters related to ch...
diamond like carbon (dlc) film was grown by hot filament chemical vapor deposition (hfcvd)technique. in the present work, we investigated the quality of the dlc films groew on the substratesthat were coated with various metal nanocatalysts (au and ni). a combination of ch4/ar/h2 rendersthe growth of carbon nanostructures technique (diamond like carbon). the utilized samples werecharacterized by...
Rhombellanes are mathematical structures existing in various environments, in crystal or quasicrystal networks, or even in their homeomorphs, further possible becoming real molecules. Rhombellanes originate in the K2.3 complete bipartite graph, a tile found in the linear polymeric staffanes. In close analogy, a rod-like polymer derived from hexahydroxy-cyclohexane was imagined. Further, the ide...
the price of single point diamond tools with a sharp tip is very high due to complex machining process and highly expensive machining equipments. yet, the performance is not quite satisfactory. in this paper, we have presented a very simple and cost effective machining process for the sharpening and polishing of diamond stylus using low energy reactive ion beam machining (ribm). in our method, ...
In this paper, for the first time, an analytical equation for threshold voltage computations in silicon-on-diamond MOSFET with an additional insulation layer is presented; In this structure, the first insulating layer is diamond which covered the silicon substrate and second insulating layer is SiO2 which is on the diamond and it is limited to the source and drain on both sides. Analytical solu...
Single crystals and polycrystalline diamond films of several thicknesses were deposited using oxygen/acetylene combustion flame technique. The substrate used was pure polycrystalline molybdenum subjected to mechanical polishing. Quality and microstructural characteristic of diamond produced were investigated using X-Ray diffraction, Raman Spectroscopy, Scanning and Transmission Electron Microsc...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید