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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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The Interplay of Iron and α-synuclein in mediating Neuroinflammation in Parkinson’s Disease
Neuroinflammation is implicated as a contributive factor to neurodegeneration in Parkinson’s disease (PD). Increased iron accumulation and deposition of -synuclein within Lewy Bodies in PD brains have been observed. It has been hypothesized that unbound iron is able to react with H2O2 to generate free radicals. Using the Divalent Metal Transporter-1 (DMT1) as a vehicle to transport iron into the brain, a DMT1 transgenic mouse model (DTg) was generated to recapitulate iron deposition in PD. The DTg was crossbred with the SNCA (synuclein) transgenic mouse to produce a DMT1_SNCA (BTg) mouse model to study the link between iron, -synuclein and neuroinflammation in PD. Our hypothesis predicts that iron exacerbates -synuclein toxicity by inducing larger inflammatory responses and consequently compromising functions of biomolecules. Our study shows that –synuclein triggers a low-grade inflammatory response by microglia and astrocytes while iron exacerbates -synuclein toxicity by eliciting immunological responses mediated by glia cells in the brain observed both in the DTg and BTg mice. Elevated levels of nitrated proteins were observed in the DTg, suggesting the role of iron in inducing nitrosative stress via upregulation of iNOS in glia cells. With the BTg mice, we hope to understand the effect of iron accumulation as an environmental stressor in aggravating -synuclein toxicity which may lead to the selective demise of dopaminergic neurons.
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Drawing versus Clay
1. Purpose of Research / Project The purpose of this research was to find out whether clay has any diagnostic value as a three-dimensional medium compare to drawing which is two dimensional medium and to determine if learners would prefer to work with clay or to rather draw a picture when depicting their ″feeling-stories″. Furthermore to do research on the effect that different coloured clay has on the emotions and behavior of learners during therapy. 2. Procedure A number of learners from different backgrounds, ages and cultures were used in this empirical research. They were asked to draw a ″feeling-story″ with a two-dimensional medium and then depict a ″feeling-story″ with different coloured clay which is a three-dimensional medium. Afterwards they had to describe their stories. They also had to choose what they liked best-the two-dimensional medium (drawing) or the three-dimensional medium (clay). 3. Data From the results it was clear that clay projections have diagnostic value. The learners were able to communicate their ″feeling-story″ better by using the three-dimensional figures in a verbal and non-verbal way. Through actions and the choice of coloured clay they used, they could portray and describe their emotions and symbolic messages. This indicated that they enjoyed the clay projections more than the drawings they made. 4. Conclusion From my research I found that clay as a three-dimensional medium has diagnostic value and can be applied as a supplementary projection medium. Different coloured clay can be associated with different emotions and behaviours in children. More learners preferred to work with clay (three-dimensional) as a medium in depicting their ″feeling-story″ rather than drawing two-dimensional pictures.
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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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Extreme Mouse Mobile
Objective To design build and run 5 Mouse mobiles – vehicles which use mousetraps as their only source of energy. Targets- • Go up a ramp • Raise a flag • Hit something and set it free • Deliver something • Catapult Details These mouse mobiles are original creations which include some commercially produced parts. They are powered by single spring driven standard wooden mousetraps. They are 5 in number each being used for the respective tasks. Basic structure Each mousetrap consists of a 2 parallel wooden planks which has 2 holes drilled on either sides for the rear and front axles. A rod is used as the axle and CD disks are used as wheels. The mousetrap is attached to the planks. Movement and Locomotion To move the mouse mobile a string is connected to the rear axle. The string runs through 2 pulleys which change the direction of the applied force and are attached to the hammer of the spring. When the vehicle is pulled backwards on the floor tension is created in the string (as the hammer is stretched) which gets stored in the form of spring energy. When the wheels are released on the floor the rear axle starts rotating hence propelling the mouse mobile forward. Completion of objectives 1) To go up a ramp For the required task a high amount of torque would be needed .That will be sufficiently provided by the spring energy. 2) Raise a flag For the required task a rod is placed on the wooden platform. The flag is placed at the bottom of the rod; it is connected to the hammer of the mousetrap using a string. The spring and the rod are placed in the opposite directions. When the hammer is released after being stretched it pulls the string and raises the flag. 3) Deliver something For the required task 2 mouse mobiles are used. A platform of any hard and light material is attached to the rear of a mouse mobile. After reaching the desired location, when the hammer of the primary spring is fully relaxed it hits the catch of another stationary mouse mobile. The hammer of the respective catch is connected to the platform using a string. Upon activation the hammer is released, the platform is pulled with extremely high speed and the materials on the platform, due to their moment of inertia fall down. 4) Hit something and set it free. For the required task 2 mouse mobiles are used. A small mousetrap is attached to the front of the mouse mobile which is in contact to the required object. The other mouse mobile on reaching the above vehicle hits its catch using its hammer. The hammer of the stationary mouse mobile is released and the object is hit and set free. 5) Catapult For the required task 2 mouse mobiles are used. A mousetrap is attached to the front of stationary mouse mobile which is attached to a strainer and the object to be catapulted is placed inside it .Another mouse mobile approaches is and hits the catch hence activating the hammer and the object is catapulted.
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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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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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IF鋼在鹽酸溶液中之腐蝕速度隨鹽酸濃度之增加而增加。12M之硝酸溶液對IF鋼具最強腐蝕性,而最低(0.1M)及最高(16M)濃度之硝酸溶液對IF鋼之腐蝕性則相對較弱。硫酸對IF鋼之腐蝕速度則由低濃度至高濃度呈現極大變化,當硫酸濃度由0.1M漸增至3M時腐蝕速度亦隨之增加,爾後腐蝕速率減小,至硫酸濃度由8M時反而呈現極大之重量增加。由於表面腐蝕層不適於XRD分析,故由EDS結合FTIR分析得知H?SO?/8M-24hrs.情況下試片表面之腐蝕層為Fe?O?。由SEM觀察發現腐蝕速率較大之條件,如HCI/12M-1min.及HNO?/12M-1min.處理過後,試片表面甚至出現具晶體對稱性之蝕恐。由本研究之初步成果發現:是溫下可以利用中等濃度(如8M)之硫酸液來處理鋼鐵,使之表面生成一緻密之氧化鐵(Fe?O?),達到防蝕之效果。IF (interstitials free) steel was processed in various aqueous acid solutions to observe the corrosion behavior. The corrosion rate of IF steel in HCI(aq) increases with the concentration of HCI(aq). HNO?(aq) with concentration of 12M was observed to be the most aggressive for IF steel. The corrosion rate of IF steel in H?SO? solution increases from 0.1M to 3M and then decreases gradually with the concentration. A large amount of weight gain even observed when the concentration was 8M. The protective layer produced during H?SO?/8M-24hurs. treatment was analyzed to be Fe?O? by using SEM (Scanning Electron Microscope), EDS (Energy Dispersive Spectroscopy) and FTIR (Fourier Transform infrared). Etch pits with crystallographic symmetry were observed on the specimens treated with conditions HCI/12M-imin. and HNO?/12M-1min. Processing condition H?SO?/8M-24hrs. could be employed in corrosion prevention for IF steel under ambient environment.
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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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流體旋轉時,外圍及底部流體,因槽壁及槽底摩擦力的影響,流速較慢,相對的壓力也較大,導致外圍的水流會轉入中心。發現本實驗的渦流為強迫與自由漩渦組成。實驗中,探討f(轉動器的頻率)、H(總水深)、y(?入深度)、R(轉盤半徑)四者與角形數間的關係。若y、R 愈大、H 越小,隨著f 的增大,可觀察到的形狀邊數越多;反之,若y、R 愈小、H 越大,則f 愈高,所形成的圖形半徑愈大,易超過轉盤,不易觀察。依白努利方程式,外層水流的流速較慢,而內層水流的流速較快,故外層壓力大而內層壓力小,水會由外往內流,而此渦動流於轉動液面產生的剪力,可能為產生N 邊形漩渦的主要原因之一。流體旋轉系統中,因轉動而產生流體離心力與內外層壓力差交互作用下,於某特定相關的因素條件下,形成特定角形數漩渦,是本實驗的重要發現。When fluids are in rotation, fictitious force given by the container brings about the relative decrease of speed of the bottom and outer layer of water, which causes its pressure to increase, and water to spin inward, resulting in a vortex motion with N-corner polygons formed at the surface of the rotating plate. During this experiment, we discover that the vortices consisted of free and forced vortex and the polygons vary as control parameters f(rotation frequency), H(height of fluid), y(depth of the plate), and R(radius of the plate) change. The larger y and R are,the smaller H is, the more corners show up as f increases. On the contrary, the smaller y and R are,the larger H is, few polygons are identified since the rotating radius of polygons are larger than the plate. According to Bernoulli’s principle, smaller velocity of the outer-layer water causes water pressure to increase and water to spin inward. During this process, shear force is developed at the surface of the rotating fluid, which we believe is the main cause of N-corner polygons. In a rotating system, the interaction of centrifugal force and differential pressure causing a certain Ncorner polygon to be formed under different controlled parameters is our main discovery.
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This study was to explore the nature of two basic constitutes of the regular pentagon,With these two constitutes, the regular pentagon could be multiplied into any times. We used four multiplication methods (m2 = 2m1 + n1 、n2 = m1 + n1 、m2= k2m1 、n2= k2n1、a2 = a1 + 1、a2 = a1 + ) to show how the regular pentagon could enlarge and to verify that the enlarged regular pentagons derived from computer did exist. By integrating these four multiplication methods, we were able to arrange regular pentagon of any length of side, and evidenced the equation was
( If the side length of a regular pentagon is a form of m,n is the number of A,B respectively )
We further proved that the first multiplication method could be developed into a new modified method, which could divide a regular pentagon with a given side length into a combination of A and B. But only when the x and y of side length of a regular pentagon could be divided by a natural number, k, and made x/k into an item of the Fibonacci Sequence and y/k a successive item.
When we tried to verify if any regular pentagon could be constituted by other smaller regular pentagons, we also found that it was un-dividable only if the length of pentagon side were ( the number of A, B were the 2n and 2n-1 item of Lucas Sequence). Otherwise, any regular pentagon might be able to be constituted by other smaller regular pentagons.
本研究是以正五邊形的兩個基本組成元素(B)作為討論對象,利用此二元素可以將正五邊形做任意倍數的放大。我們共使用4種繁殖法則(m2 = 2m1 + n1 、n2 = m1 + n1 、m2= k2m1 、n2= k2n1、a2 = a1 + 1、a2 = a1 + ) 來說明正五邊形的放大情形,並利用此4 種繁殖法驗證電腦運算出的放大圖形確實存在。利用這4 種繁殖法則的改良與整合,已達到能排出任意邊長之正五邊形的目標,並能計算並證明出其通式為。
(若正五邊形的邊長為形式,m、n代表、的個數)
更特別的是,我們能用第一繁殖法反推出一種方法,將給定邊長的正五邊形利用簡單的切割方式分成由A、B 組合成的形式,但只有正五邊形邊長之x、y 值可同除以任一自然數k 而使 x/k 為費波那契數列之一項且 y/k 為其後一項者才可以使用。
將此想法推廣至一個正五邊形能否由比他小的其他五邊形組合而成時,我們也發現當正五邊形之邊長為時(其A、B 個數為盧卡斯數列之第2n,2n-1 項),不可分解,否則應該皆可將一個正五邊形分解成比它小的其他五邊形組合(我們也可以利用這些質形檢驗出其他正五邊形是否也為質形)。但其分解形式,不只一種,而我們推測只用兩種較小的正五邊形就能達成,我們期待能找出一或多種分解方法,能將正五邊形分解成標準的分解形式。
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線蟲補捉菌Arthrobotrys musiformis 黏液相關基因之選殖與功能界定
線蟲捕捉菌Arthrobotrys musiformis 是一種可經線蟲誘導產生捕捉網來捕捉線蟲的真菌,本實驗即針對A. musiformis 的捕捉網黏液相關基因:Manosyltransferase(AH73), β-1,3-glucan transferase(AH102), fimbrin(AH121)及mannose-specific lectin precursor(AH338)進行選殖與功能界定,希望建立這方面的研究基礎,將來能應用在松材線蟲的生物防治上。首先我們大量培養A. musiformis,萃取菌絲體的DNA;接著進行聚合?連鎖反應 (Polymerase Chain Reaction,PCR) ,利用專一性引子對 (primer) 大量增幅AH73、AH102、AH121 及AH338之基因片段;增幅後的產物經過純化、選殖,定序並進行分析比對,確認增幅之序列無誤後,以 Digoxigenin (DIG) 標示當為探針,篩檢A. musiformis 的Fosmid Library﹔目前已成功選殖出AH73 之可能基因,完成AH73 之探針製備,並以其篩檢A. musiformis 的Fosmid Library﹔呈雜合正反應之選殖株 (clones) 將以散彈槍方法(shotgun)定序,作序列組合,探索相關的基因;接下來用 Rapid Amplification of cDNA Ends(RACE) 做出互補DNA (complementary DNA , cDNA) 全長度後;最後建構基因缺失株,驗證此基因所調控的生理以及生化機能。 Nematode trapping fungus Arthrobotrys musiformis can capture nematodes by producing adhesive nets when nematodes go through. Many kinds of nematodes, including pine wood nematode (Bursaphelencus xylophilus), can be captured. Pine wood nematode causes serious pine wood disease. Therefore, A. musiformis has the potential of biocontrol in pine wood nematode. Our research focused on adhesion and adhesive relevant genes of A. musiformis :Manosyltransferase (AH73), β-1,3-glucan transferase (AH102), fimbrin (AH121), and mannose-specific lectin precursor (AH338). We try to clone these genes and carry out functional analysis. In order to achieve this goal, we used specific primers derived from previously obtained complementary DNA (cDNA), by Polymerase Chain Reaction (PCR) to amplify these genes and gained adequate quantity of genomic DNA products. After sequencing and verifying of the identity of the genomic DNA, we use Digoxigenin (DIG) to label them and use them as probes to screen the constructed A. musiformis Fosmid Library. Currently, the Southern colony hybridization is undergoing. The positive Fosmid clones against the specific probes will be sequenced completely by shotgun library to monitor the existence of adhesion related gene cluster. After working out the full length cDNA of these genes, we will use them to construct replacement vectors to knockout the adhesion related genes, creating mutants and further verify their functions through genotype or phenotype bioassay.
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