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由於想了解化學反應的微觀形態,我們設計微型化學反應裝置來比較巨觀(傳統型)與微觀(創新型)化學反應間的差異,並探討其實用及環保方面的問題。在顯微鏡底下,我們觀察化學反應的沉澱結晶及電解反應,嘗試以各項變因(溫度、濃度、聲波…等)來觀察其結晶的型態。我們已成功地將實驗藥品用量減少到一滴(約0.04ml),並以微觀的角度觀察化學反應的過程。在實驗中,發現反應進行時,粒子會不斷流動,經查證後為愛因斯坦所提出的布朗運動,並且測得硫顆粒的直徑大小約4.2 ~ 6.7 微米。不同聲波所造成硫粒子的移動速率不同,而不同溫度的部份,我們發現→每增加十度硫粒子移動速率增加約兩倍。在面積4.392×10-4cm2 範圍內大約有250~300 顆硫沉澱的粒子。本實驗成功地將顯微鏡應用在化學領域上,若將此實驗推廣,可達到污染少、觀察實驗的時間短、用量少的目標。此實驗是邁向化學微觀世界,一種值得嘗試且創新的方法。In order to compare the differences between the chemical reactions of macroscopic reactor and microscopic reactor, we have designed a device of chemical reaction and researched into the problems of their environmental protections and practical aspects. Under the microscope, we observed not only their precipitating crystal compound from the chemical reaction and electrolytic reation but their types of crystal. We have successfully reduced the dose to one drop ( about 0.04ml) and observed the process of their chemical reaction from the angle of microscopic reactor. During performing the experiment, we found the particles would keep flowing while the reaction was working. It was proved as "Brown motion" introduced by Einstein. The diameter of these particles were around 4.2~6.7μm. We find that different sound waves and temperatures,the motion speeds are quite different. And the movement rate increases about two times as the sulfer particles increase 10℃ each time .Within the measure of area of 4.392×10-4cm2,there are 250~300 sulfer particles.The experiment has successfully used a microscope in the field of chemistry. If we popularize the experiment, we can reach the goal of less pollution, fewer the dose and time-saving observation. It’s an innovation to step to the world of chemical microscope world.
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Effects of Transition Metal Ions on the Thermal Stability,Fire Retardant Properties and Rheological
A study was conducted to improve the thermal stability, fire retardant (FR)\r properties and rheological properties of ethy-lene vinyl acetate because of\r its growing use in commercial applications. The approach employed\r was to modify an organo-clay, Closite 20A (C20A), with transition metal\r ions (TMI). In this study eight transition metal salts were acquired for\r modification. It was observed that all TMI modified organoclay\r nanocomposites improved thermal stability through thermo-gravimetric\r analysis (TGA). Rheological testing was done using a parallel plate\r measuring system (PP MS) to determine the dependence of storage\r modulus and loss modulus of copper and iron modified organoclay\r nanocomposites relative to pure EVA 350. The process of gelation was\r also tested for by calculating the ratio between the loss modulus and the\r storage modulus. It was found that copper modified organoclay\r nanocomposites promoted gelation and thus decreased the fluidity of\r EVA 350. The intercalation of the TMI modified organoclays with the\r polymer matrix was determined by the use of small angle X-ray\r scattering (SAXS). Testing revealed that the intercalation was\r successful, further proving that the TMIs had improved thermal stability,\r FR properties and rheological properties,
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This research mainly talks about how someone, by observing the non-congruent patterns on the backs of the playing cards and by working with the dealer on a pre-arranged lay out, can call out the cards as if he possessed the magic power to see through them. During the card-predicting game, one can use the patterns on the backs of the cards as visual clues (Observing whether it was places upside down or not)to help figure out the probability of where the card is going to show up. Suck a mathematical formula is known as the Pigeonhole Principle. Upon an analysis of the formula, we find that when given that the value of n is greater than 24, we can successfully call out a number of cards that is greater than 2n/3 . The possibility of such mathematical studies in other directions is endless. 中文摘要: 本研究主要探討利用橋牌非對稱的牌背,猜牌者經由和傳遞牌的人的一種事先約定的方 式(排法),彷彿(魔術)透視般的將一疊牌的花色逐步猜出。其猜牌過程是利用牌背 圖案的朝前朝後的指示,配合適當的猜牌張的分配,而運用到的數學法則包含鴿籠原 理,分析與討論歸納。最後我們得到一疊由四種花色張數相等所混合的n 張牌,可猜出 的張數恆大於 2n/3 (n>24 時)。後續可研究的方向仍然甚廣。
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許多難纏的疾病,如神經退化性疾病與糖尿病,在1998年建立人類的胚胎幹細胞後,開始露出一線曙光。但就算科學家已經從胚胎幹細胞,成功引導出特殊種類與功能的細胞,預備做細胞治療時,需透過細胞核移植技術,使排斥的情形大大減少。所以當今年3月,韓國透過細胞核移植技術成功作出人類的胚胎幹細胞株時,轟動全世界。但是,他們從242顆卵,只做出一個胚胎幹細胞株,浪費這麼多卵子就牽涉到醫療倫理的層面了。既然,每一個人都要訂製自己的幹細胞株,那麼卵子的來源就很重要了。理論上,胚胎幹細胞可以分化成所有細胞與組織,當然也應該含生殖細胞在內。去年5月底,賓州大學就利用小鼠胚胎幹細胞,體外培養出型態上非常像卵子的細胞。所以,今年暑假利用兩個月時間,有個機會參與了台大醫學院婦產科的胚胎幹細胞研究團隊,稍稍瞭解了胚胎幹細胞製造成生殖細胞的過程。我們採取一種方法,先從胚胎幹細胞株,用類胚胎體(EB)的立體環境,加上 SSEA-1的篩選,與維他命A的刺激,引導至初始生殖細胞,第二步利用細胞重組的方法,利用小鼠胚胎的性腺組織,來支持這些選擇過的細胞,希望可以培養出小鼠的卵子或精子。我們從EB得到SSEA-1細胞約為全體細胞的10%,然後經過維他命A的刺激,得到SSEA-1細胞約為全體細胞的5%,這時的細胞理論上是初始生殖細胞 (PGC),但是之後的體外單獨培養或與胚胎性腺重組培養,發現成果並不是很理想。到最後,也許受限於時間還有能力,沒有得到明確的小鼠生殖細胞,但是過程中,我學習到生殖細胞的生理,胚胎幹細胞的特性,基本實驗室的細胞培養與組織染色,這些都令我印象深刻。我們認為,如果有一個適當的基因轉植的胚胎幹細胞株,例如GFP放進生殖細胞相關的基因裡頭,讓達到終點,或邁向目標的細胞群,可以自我顯現,實驗會更容易達成目標。Scientists discovered ways to obtain or derive stem cells from early mouse embryos more than 20 years ago. Many years of detailed study of the biology of mouse stem cells led to the discovery of human embryonic stem cells in 1998. Through years of experimentation scientists have established some basic protocols or "recipes" for the directed differentiation of embryonic stem cells into some specific cell types. One major problem that must be solved before human stem cell therapy becomes a reality is the threat of rejection of the transplanted cells by the host's immune system. One way to avoid the problem of rejection is to use stem cells that are genetically identical to the host. This could be achieved by the same techniques of somatic cell nuclear transplantation (SCNT) that produced Dolly. Low efficiency less than 0.5% (1/242) in Korea this March brought some controversies in ethical issues. Where and how to procure the large amount of oocytes that will be required? One source of eggs could come from the generation of oocytes from embryonic stem cells (ESCs), as described by Hubner et al. (2003) in the mouse. By the selection of primordial germ cells (PGCs) and re-aggregation with their stromal cells, we hope to derive mature germ cells such as oocytes and sperm from ESCs in this study. In this study, we have demonstrated some PGCs after sequential selection by SSEA-1 antigen and optimal culture conditions. We also proved some FE-J1 positive cells but no further fertilization was obtained after all. Further investigation about this mechanism may be needed to derive these germ cells from ESCs.
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This is a study about the solution to a chess flipping game. The game is based on a 4*4 game grid. First, place some chesses on the grid randomly to start a game. Move any chess by jumping over one or two neighboring chesses in the same row (left or right), same column (up or down), or on the same diagonal. Chesses which get jumped over should be flipped. The ultimate aim is to make all the chesses upside down. In this study, I try to find the rules of the beginning arrangement that ensure solution. Here are the steps I take: First, break the restriction of the 4*4 grid, and set the coordinate system. Second, find out a few “basic illustrations” that can be solved and moved in order to cope with certain complicated problems. Third, with “basic illustrations”, find the rules applying to games on n*n grid. 這是關於翻棋遊戲的可行解之探討。棋盤是一個4*4 的方格,遊戲開始時在棋盤上任意擺上一些棋子,均是正面朝上,利用相鄰棋子的水平、垂直、斜向跳躍,棋子被跳躍過一次則翻面一次,遊戲目的在於使所有的棋子都翻為反面。我要探討的是關於棋局可解不可解的問題,找出棋盤上可解棋局的規則。研究步驟大致如下:一、打破棋盤4*4 的限制,將棋盤座標化。二、找出若干個可解並可移動的「基本圖」。三、利用基本圖,找出n 列棋盤可解的規律。
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數字波是探討在直線上的起始點、位移速度、總數相互變化的節點關係。在直線上,將全部格子數做為總數(m),開始彈跳的點為起始點(i),每次彈跳的格子數為位移速度(s),被踩到的格子就是節點。節點是由位移速度和起始點決定,起始點本身可視為節點之一,之後的節點是由起始點加n 個位移速度產生。我們分別以三種型式討論:起始點等於位移速度,總數增加:使起始點和位移速度所代表的數字相同的彈跳。節點呈2、s、s+2…起始點固定,位移速度與總數增加:觀察位移速度和總數的關係。兩節點的和=s+2位移速度固定,起始點與總數增加:探討起始點和總數的關係。發現節點隨起始點有規律的變化在上述討論的型式中,我們再進一步將位移速度分為質數和合數,進而依其因數變化,可觀測到很多特殊的節點變化。The number wave is to discuss the relationship of the starting point, the moving speed, and the variations of total amount. In straight lines, let all the trellises be total amount (m), and let the starting jumping point be the starting point (i). The trellis number of each jump is the moving speed(s). The trodden trellises are knots. And knots are decided by the moving speed and the starting point. The starting point itself can be viewed as a knot. The following knots produce with the starting point and n moving speeds. We respectively discuss them in three types: When the starting point equals the moving speed, the total amount increases. The number of the starting point is the same with the jumping moving point; the knots are 2, s, s+2…. When the starting point is fixed, the moving speed and the total number increase. From observing the relationship between the moving speed and the total number, the sum of two knots is s+2. When the moving speed is fixed, the starting point and the total number increase. After our research into the relationship between the starting point and the total amount, we find the knots have regular variations with the starting point. From the types discussed above, we further divide the moving speed into prime numbers and non-prime numbers. Furthermore, according to the factor variations, we can see a lot of specific knot variations.
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COP8 is the second unit of COP9 signalsome. In the comparison of BLAST ,we found that\r LLPC14 cDNA and the protein sequence are quit similar to the COP8 of Arabidopsis thaliana\r Therefore, we are interested in the role that COP8 plays in the photomorphogenesis and try to find\r the length of the sequence. So far, no result is obtained about the 3’-RACE, but we’re surprised to\r find that the sequence found in 5’-RACE is shorter than what we’re know, which suggests the RNA\r length of the cDNA used in the RACE combination has decreased.\r Although the final results of the COP8 5’and 3’-RACE haven’t been achieved, it is sure the\r COP8 is highly-conserved in many species. Since the similarity between LLPC14 and the COP8 of\r Arabidopsis thaliana is as high as 90 percent, we used the COP8 of Arabidopsis thaliana to detect the\r COP8 protein in pollen.在過去種綠豆芽的經驗中,不難發現它本身因為環境的不同,而有不同型態白化\r 的現象,例如:黑暗下萌發的豆苗。但尚未深入去理解白化的原因;而在後來的種植\r 經驗上,也發現有許多令自己覺得困惑的相同處。\r 在高二的生命科學第四章中,有提到光照與黑暗生長的植株,在構造比較上有明\r 顯的不同;其中,提及植物的活性組織存在「光敏素」(phytochrome),此色素蛋白的\r 存在於光照後,會引發一連串反應,至此,也稍微了解植物的萌發反應的差別。\r 故藉由個人在中研院植物所的資優生培訓過程,便以此為前題,進一步探究植物基\r 因組COP 8 與白化現象的相關性
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Energy-Transformation Railway System
There are numerous problems caused by today's railway system. This makes Hong Kong a less attractive place to live in. We have to tackle these problems in order to make Hong Kong a better place. Our model can recycle the energy dissipated in the rail vibration, reuse the sound energy produced by the wheels and the rail by a sound energy conversion system, recycle the wind power in the tunnel by a new type of wind turbine, the Wind Power Generator Underground (WPGU), recycle the thermal energy produced by the air-conditioning system of railway stations by a new system, the Thermal Energy Conversion (TEC). When the rail is bent, the magnets attached to it are also pulled down. When the rail returns to its original position, the magnets attached to it are pulled out of the coils. In both cases, the magnets move against a force. The work done to move the magnets against the force is converted to electrical energy. Also, the bottom of the MTR is designed to be curved. The sound waves produced by the contact point of the wheels and the rail directing towards the bottom of the MTR would be reflected to an elastic material which has a number of magnets attached to it and corresponding number of solenoids are fixed on the ground below the magnets. Sound energy can be converted to electrical energy in this case. When a train approaches or passes through the section that the WPGU is installed, wind is generated. The wind forces the wind turbine to rotate at a certain high speed. The turbine transmits the rotation to the coils in the dynamo, and hence electricity is generated. Heat released from the air-conditioner is absorbed by water. The hot water is then pumped into the system. As the hot water in the pipe flows through the evaporator, liquid ammonia inside will evaporate and flow into the electricity generator. Inside the electricity generator, the gas will push the turbine to rotate and hence electricity is generated. The ammonia gas is then condensed in the condenser and flows back to the evaporator. Hence ammonia is used circularly. In order to explain our principle, we would like to introduce the Lenz's Law, an induced current flows in such a direction as to oppose the movement that started it, the Faraday's Law of electromagnetic induction, the induced electromotive force in a circuit is equal to the rate of change of magnetic flux through that circuit, the Law of Conservation of Energy, energy can neither be created nor destroyed, but can transform from one form to the other.
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綠色親善大使之誕生-生物可降解性奈米複合材料的研究
近年來,由於科技的進步,導致合成性高分子材料大量開發利用,雖然便利 了人們的生活,卻造成許多環保問題,例如:資源的消耗,以及對環境的污染。 然而「生物可降解人工合成的聚乳酸高分子」和「天然的幾丁聚醣高分子」均具 有優良的生物可相容性及生物可分解性,添加無機層狀蒙脫土可補強其機械性質 之不足。本實驗之目的是以生物可分解之合成性高分子聚乳酸作為主體,再和經 有機化改質後的蒙脫土摻混而製備出聚乳酸/蒙脫土之奈米複合材料。 本實驗主要分為三大部分: (一)以界面活性劑對蒙脫土進行改質 (二)製備聚乳酸/蒙脫土奈米複合材料試片 (三)對試片進行生物降解性測試 此外,本實驗以X-ray 繞射儀(XRD)檢測改質後蒙脫土層間距離的變化; 場發射電子顯微鏡(FE-SEM)觀察生物降解後複材之表面型態;膠體色層分析 儀(GPC)檢測生物分解前後複合材料之分子量的變化;DMA 檢測複合材料之 機械性質;TGA 檢測複合材料之熱穩定性Thanks to the development and advance of modern technology, the synthetic polymers have been put in wide use. Though the synthetic polymers provide convenience for our lives, they also bring about many environmental problems, such as consumption of natural resources and environmental pollution. Nevertheless, both biodegradable man-made PLA(Poly Lactic Acid)and natural chitosan contain good biocompatibility and biodegradability. Else, adding MMT(Montmorillonite)into PLA can modify the mechanical properties. Our experiment aimed to prepare the PLA (Poly Lactic Acid)/ Montmorillonite Nanocomposites by adding organo-modified MMT into the biodegradable PLA. The experiment underwent three phases:(1) modifying MMT by means of CTAB(n-Hexadecyl Trimethyl-ammonium Bromide, CTAB ) and chitosan (2)preparing PLA(Poly Lactic Acid)/ Montmorillonite Nanocomposites (3)testing the biodegradability of the Nanocomposites we prepared. While conducting the experiments, we made use of the XRD(X-ray Diffraction)to examine the change in MMT’s layer thickness. The SEM(Scanning Electron Microscope)was also employed to observe the surface pattern of the Nanocomposites, and used Gel Permeation Chromatography (GPC)to examine the decrease of the Nanocomposites’ molecular weight. Moreover, we also used Dynamic Mechanical Analysis (DMA)to test the mechanical properties of the Nanocomposites(Tensile testing). Last, we test the thermal stability of the Nanocomposites by using Thermogravimetric Analysis (TGA).
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本研究自2002 年4 月至2003 年5 月為止,共14 個月,於台北市金面山區\r 南麓溪谷及生態池,以Twitty 去趾法(toe-clipping method)對拉都希氏赤蛙(Rana\r latouchii)進行族群特性和生殖策略之研究。\r 研究期間內共標記了580 隻(包含畸形蛙65 隻),而雌蛙有190 隻(包含雌畸\r 形蛙19 隻),雄蛙有350 隻(包含雄畸形蛙43 隻),無法分辨公母者有30 隻(無畸\r 形蛙),未判定公母者有10 隻(包含畸形蛙3 隻)。\r 在族群特性的部分,拉都希氏赤蛙之雌、雄個體吻肛長、體重及吻眼比皆\r 有顯著性差異(p
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The purpose of the Actuator is to create a practical device that passively exercises\r the lower legs to help prevent blood clots, Deep Vein Thrombosis (DVT), in\r wheelchair-bound individuals of any age. The secondary purpose of the device is to\r improve range of motion of the lower legs and speed the recovery of their leg action. It is hoped that this invention will help to prevent DVT, and allow some people to even use their legs again, through passive or active muscular motion. The invention was produced using a number of prototypes and design sketches. Although the current model is quite functional, as it keeps the users legs in motion, it is still in the prototypic design stage.\r The Actuator is a simple to use, easy to retrofit device. It is also portable and will be\r able to attach onto the front of any wheelchair. It harnesses the motion of the wheelchair to drive the users legs in a circular motion.\r The invention was tested in a closed and controlled environment: the duration of the\r Actuator’s use was constant, a doctor was present to take blood pressure and heart rate, and the rotation speed of the user’s legs was controlled by keeping the wheelchair speed constant. The data was collected by monitoring heart rate and skin surface temperature of healthy individuals, and blood pressure and heart rate of a wheelchair bound individual.\r As seen with both experiments (wheelchair bound, and healthy individuals) heart rate\r increased. In addition, the wheelchair bound individual’s heart rate also noticeably\r increased, with an evident increase in blood pressure as well. However, skin surface\r temperature is sensitive to surroundings and often provides little indication of deep vein blood flow, thus the skin surface temperature measurements were too inaccurate for any conclusions to be formulated.\r The inventor’s grandmother had developed DVT’s in 2005, and passed away because of them. Had she been given an Actuator it may have prevented such a tragedy. Her death was the driving force behind the project’s development. Over the time period that this project has been in process, the true potential of this invention has been realized.\r I truly believe that it will revolutionize the way that we treat people in wheelchairs, and the way people in wheelchairs can treat themselves.
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In The Name Of Allah
All Praise be to Allah and Pray and Peace be upon to the Prophet\r of Allah ( Mohammad peace be upon Him )
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