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The objective of this project is to investigate styrene butadiene rubber(SBR), which is the most important synthetic rubber. The project contains production methods, properties, safety methods and applications for emulsion SBR. The goal is to determine which production technique of SBR is the most beneficial. This is based on the chemical and physical properties of the final product and its quality. The process that is used in the project is emulsion SBR with combined coagulation stripping. The rubber production plant is a profitable venture. The total capital cost is estimated around $31,361,572, with an annual production cost of about $67,281,378 yearly, generating revenues of $73,801,760 per fiscal year, with an interest rate of 5%. The life of the plant is 15 years and would produce 50,000 ton/year.
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Synthetic Analogs of Smoothened Intracellular Loop as Potent Inhibitors of Cancer Cells Growth
Smoothened (SMO) is a critical component of Hedgehog (HH) pathway that is essential for stem cell renewal and is dysregulated in many cancer types. SMO is a seven transmembrane domain protein with three intracellular loops. Primary structures of SMO intracellular loops are unique and very much conserved among the species, which is indicative of significant and unique roles in intermolecular or intramolecular interactions. The hypothesis was that synthetic analogs of SMO intracellular loops may function as HH pathway inhibitors. Derivatives of second intracellular loop were synthesized utilizing automated solid phase peptide synthesis based on Fmoc chemistry. Peptides were purified by HPLC and there anti-proliferative activity tested on melanoma cells by MTT assay. Targeted libraries of second loop derivatives of varying length helped to identify compounds that inhibited the growth of melanoma cells in vitro with IC50 in nanomolar range. The most potent of antagonists obtained is the palmitoyl derivative of the Nterminal half of the loop, and is 12 residues long. Lipidation proved to be critical for the activity. Remarkably, retro-inverso versions of the peptide, in which all amino acids are in D-configuration, are even more potent and have IC50 in subnanomolar range. Circular dichroism studies proved that the peptides are folded both in aqueous solutions and in the presence of lipids mimicking the membrane environment. They also suggested that retroinverso analogs have a different fold, which may contribute to higher activity. The new compounds are promising drug candidates and present convenient tools for solving the\r mechanisms of hedgehog signaling.
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Viable Energy From Ocean Waves
(a) Purpose of Research To investigate the wave conditions offshore along the South African coast to determine wave heights, intervals, and patterns. These results have demonstrated the power potential of ocean waves and identified sites for offshore power stations. The waves off of the South African coast are the most viable, as they have wave heights of between 2.7m (9ft) and 14.6m (48ft). It is also to assist in the development of my power station design, through research into offshore wave composition, principles, periods and characteristics. (b) Procedures I have used various calculations including the surface pressure of salt water per square meter to calculate the potential power produced by a buoy. These figures have been expressed in Kilowatt Hours, and are then able to be divided by the known consumption of a single USA household in 1 year. A figure of the amount of households that can be supplied by a single generator will then be reached. An approximate power output for a single buoy is between 200 and 300 homes per year (Dependant on wave height) A concept for a maintenance free electrical generator suitable for marine use has been investigated. The design will be made as: ● A working demonstration model capable of producing electricity, which consists of a Rotary Induction Generator, ● a scale model to show the appearance of one such generator & ● A large scale model to show how generators can be congregated to form a power station offshore. (c) Data Utilising the calculations of potential power output and the wave data, the financial viability of the generator has been calculated, in relation to current fossil fuel power stations, down to a cost per Kilowatt. Wave data from international marine monitoring websites that provide real time wave condition graphs, have been tracked by myself daily for over 1 month and recorded to provide a large data resource. This provides wave heights of multiple weather systems as well as averages. Costs have been investigated from Internet sources for electrical integration to the national power grid, as well as the generator manufacture. These are estimates, as the exact specifications of my device cannot be finalised without further prototypical research. (d) Conclusion With conclusions reached by thorough research into wave dynamics, weather patterns and their effects on wave heights, Rotary induction power generation and costs related to multiple power systems, I intend to demonstrate fully to the International Electrical Producers, that coal fired power plants are more costly and environmentally damaging than my revolutionary concept for a truly economically viable, ocean based generator system.
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We study the effect of dark energy on the evolution of cosmic structure in a scenario where the dark energy is treated as free particles and thus can be localized. By theoretical derivation and numerical simulations, we found that:
1. The dark energy particles gain kinetic energy from a moving dark matter particle through gravitational interaction. Due to energy conservation, the dark matter particle will slow down with time
Ek(t) = Ek0 - 9 × 10-5[|1+3w|ρDE]1.92t where Ek(t) is the kinetic energy of the dark matter particle,Ek0 is its initial kinetic energy, w is the coefficient of equation of state for dark energy, ρDE is the mean energy density of dark energy, and t is the time.
2. The formation history and structure of galaxy clusters are different in the presence of localized dark energy. The more the localized dark energy, the earlier the formation of the cluster core. In addition, the kinetic energy Ek(R) as a function of R will be different if the ρDE is different. Thus we can compare the observed Ek(R) of clusters with our results to deduce the ρDE in our universe. The results here can be applied to the observations in the near future.
我們探討宇宙結構演化受到可局部叢集之黑暗能量粒子的影響。藉由理論推導及電腦模擬,我們發現:
一、黑暗能量粒子會透過重力交互作而從運動中的黑暗物質粒子獲得力學能。因力學能守恆,黑暗物質粒子的速率會減慢,滿足
Ek(t) = Ek0 - 9 × 10-5[|1+3w|ρDE]1.92t
其中Ek(t) 為黑暗物質粒子的動能,Ek0 為其初始動能,w 為狀態方程式係數,ρDE 為黑暗能量的平均密度,t 為時間。
二、星系團的形成過程及結構,會因可局部叢集之黑暗能量的存在而改變。黑暗能量越多時,星系團的核心會越早形成。而且動能 Ek(R) 隨著至星系中心距離R 的變化,會因 ρDE 的不同而不同,因此可以將量測到的 Ek(R) 和這裡的結果比對,推導出宇宙中的 ρDE 。 這些研究成果將可直接應用在未來的觀測結果上。
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Tea is the most widely accepted and consumed beverage worldwide due to its characteristic aroma and taste. Recent studies have provided the strong scientific basis for understanding the health promoting effects and cancer preventive actions of tea. The components of tea especial the catechins are varied with the conditions of making tea. To understand and determine the chemical composition of tea is very important. Some investigations of the parameters on the storage and making of tea were carried on in this study. The kinds of tea studied were including black tea, oolong tea, green tea, and instant tea bags. A high performance liquid chromatograph combined with UV detector and mass spectrometer used to analyze the components of tea. The results showed that the composition of tea solution is dependant of the exposure of light. One of the components of tea, (-)-epicatechin methylgallate (ECMG) was oxidized to quino form. The concentrations of (-)-catechin gallate (ECG) decreased and one of new compound (M.W. 442) produced with increasing the storage time. From the results show tea made with cold water is better than that made with hot water. The ingredients in green tea were changed faster than those in fermentative black tea and oolong tea. The components of tea can be kept unchanged for a long time at low temperature. In refrigerator, the time can be extended to overnight. 茶由於其具有特殊的芳香氣味及口味,廣泛地被世人用為飲料,近年來的研究證據顯示茶具有促進身體健康和防癌功效,但茶中成分之變化,尤其兒茶素隨茶的種類、茶沖泡保存方式及置放時間而有所不同,因此對於茶中成分及沖泡方式的認知是一門重要的課題。 本實驗主要是探討茶沖泡時間及貯存條件,對於茶液所含兒茶素變化的影響,探討的茶包含紅茶、烏龍茶、綠茶及其茶包。並使用質譜儀及高效能液相層析質譜儀配備紫外光偵測器分析茶液中之成分,實驗結果顯示成分變化速率以未發酵的綠茶較發酵的紅茶和烏龍茶快;低溫儲存時,亦可延緩茶液成分的變化,例如加蓋並存放於冰箱,則茶置放至隔夜其成分均未改變;同時結果顯示成分產生變化者,主要為兒茶素氧化,如將多酚類氫氧基經氧化變成?(quino) ,其次為斷裂再產生聚合其中綠茶以不照光變化較大。本研究並經實驗發現如果以冷開水沖泡綠茶20~30分鐘,咖啡因的溶出量雖略多於沖泡2分鐘的熱茶,但各種兒茶素的溶出量卻遠高之,尤其置放至隔夜茶液成分仍無氧化現象。
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Synthesis and Characterization of Starch-Nanosized Calcium Phosphate Composites
Nano-sized calcium phosphate was used in the synthesis of starch-based composite plastics to provide a cheap but sturdier biodegradable alternative to petroleum derived plastics used in film packaging. Nano-sized calcium phosphates were produced from the precipitation reaction of calcium nitrate tetrahydrate (Ca(NO3)2 ‧ 4H2O) and phosphoric acid (H3PO4). The nanoparticles were co-extruded and molded with thermoplastic starch (TPS) at ratios of 0%, 1%, and 5% by mass. Tensile strength and elongation percentage of the resultant composite plastics were tested in three replicates. The results show that there is a significant difference between the tensile strengths of the 0% and 5% calcium phosphate composites at a 5% level of significance. The trend between the composite’s tensile strength and percentage calcium phosphate follows a geometric progression, enabling a projection for the 10% nano-calcium phosphate to have a tensile strength of 10 MPa, the average tensile strength for low-density polyethylene (LDPE). This shows that it is feasible to synthesize a 10% nano-calcium phosphate-TPS plastic that can be a viable substitute for LDPE plastics in film packaging, paving the way for the commercialization of starch-based plastics. The use of biodegradable plastics with improved physical characteristics will lessen consumer dependence on petroleum derived plastics and solve the environmental issues brought about by the use of such plastics.
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對4 × 4 方格表中計數問題的二個解題方法(1..解方程式的方法, 2.分割圖形的方法)作分析和研究後,首先我推廣分割圖形的方法來証明 : “好的n × n 方格表” 存在若且惟若n 為偶數。同時証明這種“好的n × n 方格表”內所有n2 個數的總和f(n) 為n(n+2)/4。當討論一般的n×m 方格表時,發現分割圖形的方法盲點,無法繼續推廣來証明。再經過深入分析與推廣解方程式的方法,藉由n×m 變數方格表,我們終於找到構造所有“好的n × m方格表”的方法。同時計算“好的n × m 方格表” (n≦m)內所有mn 個數的總和f(n,m), n≦7和証明好的nxm 方格表會有2(n+1)行一個循環的現象。We first studied two solution methods (1.solving equations,2.dissecting diagrams.) for calculations on 4x4 checkboard. Using the method of dissecting diagrams, we proved that``good nxn checkboard'' exists if and only if n is even. Furthermore, the sum f(n) of those n2 numbers in a ``good'' nxn checkboard is equal to n(n+2)/4.In studying the more general nx m checkboards, we found that the method of dissecting diagrams does not work, However, by extending the method of solving equations, and by considering nx m variable checkboards, we obtained a way of obtaining all ``good nxm checkboards.'' By way of computing the sum f(n,m) (n≦7) of those mn numbers in a ``good nxm checkboards,'' periodicity in every 2(n+1) rows is observed.
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本研究是藉由數學手法探討;如何由一疊36 張四種花色的撲克牌中,尋找出保證可猜中最多張花色的方法。研究過程是以在適當的猜牌時機,以鴿籠原理、邏輯推理、二進位、分析與歸納……等數學原理與方法,搭配巧妙的策略運用而達到目的。猜牌方法:先約定好猜牌規則,助手將36 張牌背圖樣相同但非對稱的撲克牌,以旋轉牌背的方向傳達訊息。在本研究中得出利用數學原理與方法可「經由巧妙的猜牌方法保證可以猜中26 張花色」,並提供後續研究者利用本研究之結果繼續深入探討與研究。 The study is mathematically based with reasonable explanations behind it. We are to correctly guess as many cards as possible from a deck of 36 cards, with random numbers and four different suits. We will apply mathematical methods, such as pigeonhole principle, logic inference, binary system, and analytical reduction, upon right timing. Using careful arrangement of the principles and reasoning, we can reach our ultimate goal. To state guessing: Conference between the guesser and the assistant about the guessing rules, the assistant will have 36 cards with the same exact pattern on the back but not symmetrical. The pattern of the cards will be different when rotated 180o. The only communication between the two is by rotating cards. In the process we will obtain mathematical theory and methods assuring 26 cards correctly guessed, and the study is for further and deeper discussion.
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Effect of Certain Plant Extracts on Fruit Set and The Prevention of Jatropha curcas Linn’s Insect Pests
The objectives of this study were to investigate (1) the floral biology of Jatropha curcas Linn. as well as its possible pollinators, (2) the correlation between the number of pollen on stigma and the frequency of floral visitors, (3) the attractiveness of essential oil extracts from three species of Lamiaceae, i.e. Hyptis suaveolens, Plectranthus ambonicus and Orthosiphon aristatus, to Apis florae, (4) the repellent effect of crude extracts from three species of Graminae, i.e. Imperata cylindrica, Eleusine indica and Dactyloctenium aegyptium, on Polyphagotarsonemus latus, and (5) the effect of appropriate combination between lamiacean essential oil and graminaceous crude extract on the percentage of fruit setting and insect pest protection. \r Jatropha curcas is monoecious plants with tiny male and female flowers borne on the same paniculate cyme. One plant produces 15-30 inflorescence. Each inflorescence composes of 70-120 florets, and only 4-8 florets are successfully setting fruits. Each flower takes approximately 17 days in developing from floral bud till floral opening. The appropriate time for pollination is from 09.00 am to 10.00 am. While bees, wasps, hornets, flies and dragonflies are its potential pollinators, mites, aphids and worms are its harmful insect pests. \r Three volumetric, 1, 3, 6 and 9 ml, of each essential oil extracts were separately sprayed on each observed inflorescence. According to the experiment, 6 and 9 ml of each of the essential oil extracts give similar effective outcome, However, The H. suaveolens extract at 6 ml is the most effective attractant for A. florae. because it uses less of the oil extracts.\r Four concentrations, 0.1 %, 0.5 %, 1.0 %, 1.5 % and 2.0 % of each of the crude extracts from three graminaceous plants were sprayed on each tested plants separately. Concentations above 1.0% consistently provided an effective biocidal activity against Imperata cylindrica , however 1.0% is accecptable. because it uses a reduced level of the crude extracts\r The combination of H. suaveolens’s essential oil and I. cylindrica crude extract both significantly enhanced fruit setting of J. curcas and protected the plant from Polyphagotarsonemus latus without adverse effect on its pollinators.
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(一) 本研究首先導出ΔABC等分面積線移動所包絡出的曲線方程式,其圖形是由等分面積線段PQ(其中P、Q皆在ΔABC的周界上)的中點所構成,具有3 條曲線段(分別為3 條雙曲線之一部分)的封閉曲線,形成內文所謂的「包絡區」。利用包絡區的區隔,我們找出:1.當P 點在包絡區內,則有3 條等分面積線。2.當P 點在包絡區周界上,則有2 條等分面積線。3.當P 點曲線段的端點或在包絡區外,則有1 條等分面積線。(二) 以三角形的研究當基礎,擴展到凸n 邊形(不包含點對稱圖形),我們發現:等分面積線數量之分布,仍然與包絡區息息相關,且1.凸2m +1邊形最多有2m +1條等分面積線。2.凸2m邊形,必發生內文所謂的「換軌」。因此,最多只有2m ?1條等分面積線。3.包絡曲線所分割出的區域,於相同區域其等分面積線數量相同,且相鄰兩區域數量差兩條。(三) 若凸n邊形有k個「換軌點」,則此n邊形過定點等分面積線至多有n ? k 條。(四) 若凸n 邊形為點對稱圖形(如正偶數邊形、平行四邊形),則所有等分面積線皆過中心點。1) Our study got a curve equation of bisectors of a triangle. When a bisector is moving, we get three curves. They’re constructed by the midpoints of PQ. The three parts of the three curves make a closed curve which we called “the Envelope Area”. We found out:\r 1. When Point P is in the Envelope Area, we can get 3 bisectors. 2. When Point P is on the curves of the Envelope Area, we can get 2 bisectors. 3. When Point P is outside of the Envelope Area, we can get only 1 bisector. 2) Based on our study of triangles, we found that in Convex polygons(not including Point Symmetry Convex polygons), the distribution of bisectors is related to the Envelope Area. 1. We can get at most 2m +1 bisectors in a 2m +1 Convex polygon. 2. We can get at most 2m ?1 bisectors in a 2m Convex polygon, and the bisectors on the curves will “Change the Track”. 3. Envelope curve will divide a Convex polygon into several areas. The same area has the same numbers of bisectors, and the near areas have less or more 2 bisectors. 3) If a Convex polygon has k points to change the track, it will have at most n – k bisectors.\r 4) In a Point Symmetry Convex polygon (ex. Regular 2m convex polygons and parallelograms), all the bisectors will come through the center point.
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Digital Viedo Compression Enhancement With Reduced Psychovisual Redundancy
Video compression is indispensable to web streaming and memory storage.Most video\r compression technology has difficulty to achieve high quality video at lower bit\r rates.Apparently,limited transmission bandwidth and network resources often degrade\r video signals.Thus the goal of my research was to enhance video degrade video\r signals.Thus the goal of my research was to enhance video compression performance and\r to improve visual quality.It is hypothesized that the reduction in neighboring pixels\r coding,and humans perceptual mechanisms(psychovisual)redundancy could produce a\r low-complexity geometry streams for animated visual objects.A set of algorithms is\r developed to parse bidirectional interpolation pixels into their characteristic cells,which\r vary in spectral energy and wavelength.The bits contained in these cells are vectorized and\r transformed recursively to identify lower correlations among vector arrarys for blocks\r filtering.DCT function calculates energy ratios between high spatial frequency and low\r spatial frequency,to devote most of the highest spatial frequency bits with the calculated\r energy ratios.A variable quantization method is used to measure the sensitivity of colors\r and its intensity ratios to restore any missing high spatial frequency pixels.presnted in\r mathematical intrinsic.This approach leads to the ability to compress video data that\r normally require a large amount of memory to store and high bandwidth to\r transmit,Results form the enhanced video compression experiment have attained\r 0.1bpp(256kbps,25fps)without noticeable effects comparable to the video compression\r technique that achieved 0.5bpp(1.5Mbps,25fps)in use today.
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正方形和長方形是每一個人都非常熟悉的圖形,但其中卻隱藏了非常多奇妙的“數學之謎”。 所謂「完美長方形」是:在一個長方形中 (長、寬不等),能否分割出最少大小相異的正方形。 這個研究中,首先用「草圖」的解題方法研究完美長方形,接下來利用「平面圖形」的解題方法可簡化計算的過程,最後利用「對偶關係」證明出:完美長方形的最少階數為 9 階。 進而,我們將這個問題擴展至三維空間,思索在一個長方體中(長、寬、高都不等長) ,能否仿照二維空間,分割出最少大小相異的正方體,而完成這個研究。 Square and the rectangle are figures that everyone knows well very much, but what a wonderful " mystery of mathematics " is hidden among them. What is called the perfect rectangle is whether in a rectangle (its length and width is different ) could cut apart two squares as the least difference in size . In this research, the solution approach of "the sketch map" is used to study the perfect rectangle at first, then the solution approach of "the level figure" to simplify the complicatied calculation of the solving course , and "the dual relation" is finally used to prove 9 orders are the least orders for a perfect rectangle . And then, we expand this question to three-dimensional space, considering in a cuboid (its length, width, and height is different) whether could follow the two-dimensional space model to cut apart two squares as the least difference in size, and finish this research.
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