明察秋毫-動態測微器
The purpose of this research is to create a device that is able to precisely measure small dynamic changes which cannot be recognized by the human eyes. The Vernier Caliper and the screw micrometer are common tools used to precisely measure lengths of objects. However, things which are measured by the Vernier Caliper or the screw micrometer have to be in a solid state, and the shape cannot be changed. By applying the light lever principle on Lego bricks, this research uses the LabVIEW graphical programming system to design a device which is able to automatically measure small dynamic changes. The precision of this device is higher than that of the Vernier Caliper and the screw micrometer. Moreover, this device is able to precisely detect the small dynamic changes of solids and liquids as well. Through numerous tests, the least count of the device can reach the level of 10-3cm. Also, this device has successfully measured small changes, such as the height of the liquid surface by one drop of water, the evaporation of water in one minute, and the growth of a plant in one hour. By popularizing this device, people will be able to precisely measure small dynamic changes which are difficult to be measured in a short time.
流體碰撞物體所產生的波形之研究及應用
當流體由圓管流下,在碰撞到物體後水流會產生類似駐波的形狀。為瞭解此現象的產生機制,及影響此現象的變因,我們改變流體的表面張力、流速及與碰撞物體間的距離,以探討各變因對波形所產生的影響,進而研究此現象的成因。由實驗結果發現波形會因流速加快、擋板距離增加、表面張力減少而有波長變短的趨勢,且可以用表面張力波的理論解釋。由理論推導的結果,可測量液體表面張力。由於圓球狀的外型使表面積增大,可增加液體之散熱的面積,因此可應用在水冷系統方面。A phenomenon similar to the standing wave, which occurs when a slow-velocity fluid jet collides with an obstacle, was observed. Because the free surface profile was observed to be stable, the phenomenon was not considered as standing wave. To understand the mechanism of this phenomenon and the factors that can affect the free surface profile, the surface tension of the fluid, jet velocity and the distance between the exit of the tube and the obstacle are varied to study their influences on the free surface profile. According to our experiment, the wave length is shortened when the jet velocity or the distance between the tube and the obstacle increases or when the surface tension decreases. The tendency of the investigated phenomenon can be explained by the capillary wave theory. Based on Bernoulli’s principle, continuity principle and surface tension\r equation, an ODE (ordinary differential equation) could be formulated. By using numerical method to solve this ODE, we predict the free surface profile which could match the experimental photo well. The tendency of the phenomenon can also be explained by the ODE. In order to measure the surface tension of the fluid, we wish to minimize the experiment apparatus. To enhance our assumption we use laser to locate the individual particle that we add in the fluid and calculate the velocity field of the flow jet.
利用雙雷射精密測定準靜物的極微小變位
To-be static objects, such as bridges, volcanoes, seldom move ordinarily but have mini displacement only under special conditions, like flood or earthquakes. Therefore, how to measure their mini displacement has never become fully popular with scientists’ research. Then, beginning with “ Optical Lever Theorem”, through a series of speculation and discussion, I decide to use laser ray as light source to perform an experiment ------- trying to find objects with mini displacement in our daily lives, such as revolving electric fans, engine-opening motorcycles, shaken trees, testing their magnifying effect first. Next, I try to use the control-experiment method to find out the magnifying relation and formula of the rotation angle of the plane mirror and the displacement quantity of light focus. As to the measure of mini displacement on objects, I utilize the pillar mirror as a reflection plane to research the magnifying relation of reflection light focus and original displacement quantity. The image made from the light focus of pillar mirror’s reflection, however, isn’t so perfect that I have to use a special plastic-made light-concentrating mirror, which is also called “ Fresnel Lens ”, to focalize the light for easy observation. Besides, I find out the “ function graph ” of the mini displacement quantity on to-be static objects and the displacement quantity of reflection light focus. At last, I try to build up a “ Bridge Alarm System ” of Optical Lever Theorem. 準靜物如橋樑、火山,由於平常不輕易移動,只有在特殊情況下(如洪水、地震)時,才會發生位移的現象。因此,其微小變位如何測量,一向是科學界較少探討的題目。於是,先由光學槓桿原理著手,經過一番思考、探討,決定採用雷射光作為光源,並作了第一個實驗--找生活中具極微小變位的東西,如轉動中的電扇、引擎發動的摩托車、被搖動的樹木等,先測試其放大效果。接著就試圖用控制變因的方法,找出平面鏡旋轉角度和光點平移量的放大關係和公式。至於物體微小的平移量之測量,則是利用柱面鏡作為反射面,來探討反射光點的位移與本來的平移量之放大關係。然而,柱面鏡的反射光點成像並不理想,於是用一種特製的塑膠集光鏡,又稱Fresnel Lens,將光點集中以利觀測,並且找出準靜物之微小平移量及反射光點的位移量的函數圖形。最後,嘗試建立一套光學槓桿式的「橋樑預警系統」。
奈米防蝕專家-微乳液法製備聚苯胺奈米粒子及其在防蝕應用研究
導電高分子在各面之應用非常廣泛,其中聚苯胺因價格便宜,製作簡便,使\r 其應用潛力更為突出。聚苯胺在鐵系及非鐵系金屬之防蝕能力已被證實,但由於\r 聚苯胺與金屬之附著力不良使其應用受到限制。奈米粒子所具有的表面效應、小\r 尺寸效應及宏觀量子隧道效應,使得奈米微粒材料之應用蓬勃發展。但在高分子\r 奈米微粒之製備仍屬有限。本文以微乳液法製備聚苯胺奈米粒子,以提高聚苯胺\r 與金屬間之附著力,使其防蝕能力充分發揮。國外雖已有廠家製作聚苯胺防蝕塗\r 料,但屬於商業機密無從得知其製備方法。本文所研發的微乳液法則是國內首\r 創!\r The development and application of the conducting polymer polyaniline is\r getting prosperous and popular. The capability of polyaniline in corrosion protection\r has been proved. But due to the adhesion of polyaniline on the metal is poor, the\r applications are restricted. By the way, the nanoparticles have the special effects such\r as the surface effect, the small size effect and the macro-quantum channeling effect\r make its applications are prosperous.\r In this paper, the authors utilized the microemulsion method to produce the\r polyaniline, to modify the adhesion of polyaniline on the metal in order to improve\r the effect of the corrosion protection of polyaniline in ferrous metal. The experimental\r results show that the nano-polyaniline has good adhesion on metal. The metal coated\r a layer of nano-polyaniline has the great ability of anticorrosion under different\r corrosion situations after weeks. The nano-polyaniline produced by the\r microemulsion method add the recipes invented by the authors has great potential to\r use in scale-up production in industry.
黑暗的力量
We study the magic power of dark energy and dark matter by using theoretical derivation and numerical simulations. We found that: 1. The dark energy will gain kinetic energy from the moving dark matter through gravitational interaction. Due to the law of energy conservation, the motion of the dark matter will slow down and satisfy Ek(t)−Ek0 ∝ρDE1.92 t, where Ek(t) is the kinetic energy of the dark matter, Ek0 is its initial kinetic energy, ρDE is the energy density of the dark energy, and t is the time. 2. The formation history and the structure of galaxies will be different due to the existence of dark energy. The more the dark energy, the earlier the formation of the galaxy core. In addition, the kinetic energy Ek(R) as a function of R will be different if the ρDE is different. Thus we can observationally measure the Ek(R) of galaxies, compare it will our results here, and then deduce the ρDE in our universe. The results here can be applied to the observations in the near future.
我們藉由理論的推導,配合電腦模擬的手段,來探討宇宙中黑暗物質和黑暗能量的神祕力量。我們發現:一、黑暗能量會透過重力交互作用而從運動中的黑暗物質獲得力學能,而且因力學能守恆,致使黑暗物質的速率減慢,滿足 Ek(t)−Ek0 ∝ρDE1.92 t, 其中 Ek(t) 為黑暗物質的動能, Ek0 為其初始動能, ρDE 為黑暗能量的密度,t 為時間。二、星系的形成過程及結構,會因黑暗能量的存在而改變。黑暗能量越多時,星系的核心會越早形成。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,因此可以試圖量測宇宙中星系的 Ek(R) ,然後和這裡的結果比對,即可推導出宇宙中的 ρDE 。這些研究成果,將可直接應用在未來的觀測結果上。
模擬複雜系統的演化
複雜系統廣泛地存在每個人生活的周遭,儘管這些系統在表象上有明顯的差異,卻不約而同的都呈現出臨界現象。一個簡單的物理概念卻能廣泛地使用在許多不同的場合當中,這是令人始料未及的。這份報告在尋找,是什麼原因導致這許多似乎與物理沒什麼關聯的系統,都呈現出臨界現象?以及這類系統是如何演化的?臨界現象在系統的演化歷史中,又是扮演怎樣的一個角色?一開始,先介紹臨界現象在實際系統中表現的形式,在這以文字系統作為範例。接下來,進入思考的階段,猜測系統個體間存有的關聯性,提出如何影響的假設,並建立模型。從模型結果,可以了解複雜系統隨時間演化的趨勢改變,並發現臨界現象在系統中扮演的角色以及代表的意義。這份報告有三項結論:1. 臨界現象在複雜系統中呈現的形式 2. 模型結果與實際系統十分相似 3. 臨界現象代表著系統的穩定態。The theory of Scaling Law and Universality was originally used in researching Critical phenomena, and now we find it existing in our normal life. A simple physical concept can be used extensively in different courses. This study try to find out the relation between individuals which causes Critical phenomena appear in such different courses in our normal life, and figure out the effect time brings about. To begin with, we introduce the sights of Scaling Law and Universality by exploring the formation of complicated system. Facing a complicated word system as a real example, we observe an extraordinary phenomena, and find out the Universality and Scaling Law in different kinds of linguistics. In the main part, to think further, what’s the relation between the individuals that leads to Critical phenomena? We will give hypotheses and build a model to simulate complicated system from the view of Universality, trying to find out the cause of the interaction of complicated system. From this model, we could understand: When a complicated system evolves with time, the Critical phenomena will naturally occur in this system that could be considered as dynamic equilibrium. From this study we found out(1) The Universality and Scaling Law in complicated systems, here we use linguistics as an example.(2) Under the hypotheses, the simulation is almost as same as the real result of linguistics system.(3) Time plays an important part in the Critical phenomena which can be found in many different complicated systems, and Critical phenomena symbolize a stable state of such systems.
A study to find out suitable colour to control pests of chilli plants using a colour trap
Chilli (Capsicum annuum L.) is one of the most important condiment crops in Sri Lanka. The main constrain in chilli cultivation is the Leaf Curl Complex (LCC) which reduces the quality of the pods as well as the yield. Many researches have been proven that the problem can be controlled by Integrated Pest Management (IPM) practices. Colour sticky trap is one of the mechanical methods in the IPM package which reduces the pest population successfully. Mainly three colours, namely blue, yellow and white have been identified as suitable colours for traps all over the world. This study was thus, conducted to find out the most effective colour for sticky traps to control chilli leaf curl complex in the Intermediate Zone of Sri Lanka. Traps were prepared from wooden plates of 30 x 25cm in size and the colours were applied in both sides of the plate. Both colourless and odorless vaseline was used as the sticky substance. These blue, yellow and white sticky wooden plates (traps) were fixed in 1m height from the ground level and they were used as the treatments. Six pots with 2 plants each of the variety ‘KA-2’ were used in a treatment and three replicates were sited for the experiment. All the agronomic practices were equally done for all the treatments. Number of trapped pests associated with the LCC was counted in 4, 6, 9 and 12 weeks after transplanting. The number of leaves affected by the pests in a canopy was counted in 7, 10 and 12 weeks after transplanting. The number of damaged green pods and the pod weight were taken at harvesting. The mean values of the number of pests trapped in white, yellow and blue colour traps were 162, 160 and 38 respectively. The percentages of damaged leaves in a canopy at 7, 10 and 12 weeks after transplanting in the blue trap were 89.07, 98.00 and 100.00 respectively. Those values in the white trap were 87.37, 98.90 and 93.29 and in the yellow trap were 69.03, 87.26 and 82.26. Percentages of damaged green pod weight in the blue, yellow and white treatments were 66.63, 47.06 and 45.65 respectively. These results suggest that yellow and white colours are more effective in sticky traps in pest controlling to control chilli leaf curl complex in the Intermediate Zone of Sri Lanka. Further studies are required to confirm the results.
高分子複合材料的性質、製作與分解
Synthesis of Polymer Material and its Decomposing Processes Because plastic cannot be decomposed naturally by itself, therefore, additives needed to be added to facile the decomposing process. Let us choose one common material: thermoformed Nylon 66. During the formation process, addition of glucose powder and monosaccharide polymerized will result in yielding the products of methyl cellulose, soluble starch and agar powder. Observe whether adding additives would allow changes to occur structurally, or would the elasticity be improved when exist in a linear state, or even it would form a better pH resistance property. According to the experiments, when Nylon 66 contains methyl cellulose, it can sustain the highest tension. Its coefficient of elasticity is 2 times as large as the original one. In terms of the data, we can also observe that when Nylon66 contains soluble starch, it has the lowest ability to sustain tension. Besides, it has the lowest coefficient of elasticity. And when Nylon 66 contains cellulose, it has the highest rate in the process of decomposing.As we look at the surface of polymers under 400 diameters, we can observe that the Nylon 66 with agar powder has some filiferous substance. But we have not confirmed what the matter is. 由於塑膠不能在自然情況下順利分解,所以我們在塑膠中添加其他成分使塑膠可以較易 分解。我們選定常見的塑膠—熱塑性的耐綸-66。在聚合物的製作過程中添加葡萄糖、澱粉、 洋菜粉末以及甲基纖維素,並觀察加入添加物的塑膠在結構上是否有變化?其塑膠在線型時 之張力是否有增強?耐酸鹼性是否有變化?由實驗結果我們可以得知含有甲基纖維素之耐綸 -66 所能承受之張力強度最高,且其彈性係數也比無添加物之耐綸-66 高出近2 倍;而含可溶 性澱粉之耐綸-66 所能承受之張力最小,且彈性係數也最低。此外,進行生物分解的實驗可發 現,含葡萄糖的耐綸-66 分解的速率最快。使用400 倍的光學顯微鏡可發現含有洋菜粉末的耐 綸-66 表面與其他耐綸-66 複合材料差異較大,值得進一步研究。