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Antibacterial Properties of Mānuka
Antibacterial Properties of Mānuka Mānuka (Leptospermum scoparium) is a native 紐西蘭 plant that has long been used by indigenous Maori for its medicinal and therapeutic properties, yet is relatively unknown to science. Many of our native species may contain novel compounds with practical applications in our lives. Research indicates that mānuka has anti-microbial, anti-fungal, herbicidal, insecticidal and anti-bacterial properties, and suggests that compounds similar to Grandiflorone (ß-triketones) cause these effects. This project investigates the antibacterial properties of mānuka leaves, using the bacteria Photobacterium phosphoreum for biological testing. With the recent rise in multidrug-resistant bacteria, it is now more vital than ever to utilize traditional knowledge to inform research and development of innovative new antibiotics, antimicrobials and similar biologically important compounds.
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Co-evolution of transcription factors and their binding sites in DNA
The synthesis of RNA using DNA (transcription) can be regulated by special proteins - transcription factors (TF) by binding to specific DNA regions - binding sites (BSTF). The purpose of the project is building a phylogenetic tree of orthologous groups of the each studying TF subfamilies, compare it with the tree of the corresponding BSTF motifs belonging to one orthologous group, find some common parts.
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Algae Meets Fungi: Microalgae-Fungi Co-Pelletization for Biofuel Production
Microalgae-fungi biofuel has significantly less CO2 emissions than fossil fuels, making it much more environmentally friendly. As well, unlike traditional biofuel, microalgae-fungi does not require large masses of agricultural land for production. Thus, microalgae-fungi is an optimal option for biofuel production. This is a cost-effective renewable energy source that can be used in place of regular gas in cars and other means of transportation. By determining the most effective fungi for biofuel production, the threat of the impending environmental damage from pollution can be diminished. This novel experiment determines which fungi: Aspergillus niger, Rhizopus stolonifer or Saccharomyces cerevisiae, is the most effective bioflocculant in the microalgae-fungi co-pelletization process for biofuel production. We hypothesize that when paired with the microalgae Chlorella vulgaris, Rhizopus stolonifer will be the most effective. It has a high lipid content which could enhance the overall production of biofuel. Furthermore, its negative charge will aid with attracting and neutralizing the C. vulgaris colloidal particles resulting in an easier and more efficient removal of microalgae particles. Through the process of bioflocculation, pelletization, esterification and transesterification, the most effective fungi paired with C. vulgaris was determined. This experiment was carried out thoroughly and precisely resulting in a cost-effective solution for the world's current pollution crisis.
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Satellite Modeling of Wildfire Susceptibility in California Using Artificial Neural Networking
Wildfires have become increasingly frequent and severe due to global climatic change, demanding improved methodologies for wildfire modeling. Traditionally, wildfire severities are assessed through post-event, in-situ measurements. However, developing a reliable wildfire susceptibility model has been difficult due to failures in accounting for the dynamic components of wildfires (e.g. excessive winds). This study examined the feasibility of employing satellite observation technology in conjunction with artificial neural networking to devise a wildfire susceptibility modeling technique for two regions in California. Timeframes of investigation were July 16 to August 24, 2017, and June 25 to December 8, 2017, for the Detwiler and Salmon August Complex wildfires, respectively. NASA’s MODIS imagery was utilized to compute NDVI (Normalized Difference Vegetation Index), NDWI (Normalized Difference Water Index), land surface temperature, net evapotranspiration, and elevation values. Neural network and linear regression modeling were then conducted between these variables and ∆NBR (Normalized Burn Ratio), a measure of wildfire burn severity. The neural network model generated from the Detwiler wildfire region was subsequently applied to the Salmon August Complex wildfire. Results suggest that a significant degree of variability in ∆NBR can be attributed to variation in the tested environmental factors. Neural networking also proved to be significantly superior in modeling accuracy as compared to the linear regression. Furthermore, the neural network model generated from the Detwiler data predicted ∆NBR for the Salmon August Complex with high accuracy, suggesting that if fires share similar environmental conditions, one fire’s model can be applied to others without the need for localized training.
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Pests can ruin every healthy tree’s crop within 10-15 days. This huge loss can only be detected at harvest season. If the pests have already got inside the fruits or the fruits had fallen down prior to the time of harvest. If pest-control is unconscious, 50-75% loss may occur. In Szabolcs-Szatmár-Bereg county the most common fruit production is apple. Codling moth can cause significant damage to the crops. Codling moths damage the apple directly and they are expected during the whole year. If there are signs of any nuisance we are not able to protect the crops anymore, because in this case they protect themselves from chemicals. The most important part of protection against pests is prevention. Protection can be successful thanks to insects killers and expert’s prognosis. Pheromone traps developed against wrong-doers are very practical. They are easy to use, but the problem is that the manufacturer has to check these traps repeatedly to find out about the infection, and when one has to spray the trees with the right chemicals.
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A 100% Solar Electric Vehicle: Applying high efficiency solar modules in sustainable transport
As our planet suffers the effects of climate change, it is only a matter of time before society will have to centre all aspects of development around sustainability. In the past, clean solutions for transportation have been dismissed due to the higher cost, and lower efficiency than fossil fuels. However, in the past few decades, there has been a steep decline in solar module cost, and and a steady climb towards higher efficiency. From my findings in this project, I have concluded that we are now at a point where we can embrace the clean, renewable potential which our sun offers. I have created and tested a proof-of concept electric vehicle (Solar EV), which can run indefinitely during daylight hours, provided sunny conditions. There are several mechanical features of my project which highlight the potential that renewable energy in transportation can have. Firstly the vehicle’s 500W motor is powered by 3 100W solar modules, and 3 50W modules, for a total of 450W or power generation. This means that when driving at anything less than 90% throttle, the Solar EV can run continuously without needing to stop to charge or refuel. Another design mechanism installed in the vehicle are three 12V lead acid batteries. These batteries allow the Solar EV to be powered for over 1.5 hours, which is useful during cloudy conditions, night, and most importantly, when driving through areas of shade. A unique efficiency component designed into my vehicle is the linear actuator I installed into the module racking system. This design element allows the tilt of the modules to be altered, to maximize the efficiency of the solar module array. At early or late hours of the day, it can be heavily tilted with the press toggle switch, or kept at a relatively flat level when the sun is the highest in the sky. I ran a series of trials to figure out whether or not the theoretical data matches up with the experimental results. After my series of trials, the bike was yet to run out of power. The solar vehicle reaches speeds up to 32 km/h, however comfortably glides at around 25 km/h. The linear actuator I installed allows the solar modules’ tilt to change . During different times of day or year, the sun is at different heights in the sky, however it is very important to maximize the solar potential. With the press of a switch, the module can be actuated to account for this. Lastly, regenerative braking captures the energy from braking. Using the reversible nature of a DC motor with a specialized motor controller responding to feedback from the brake actuators allows the vehicle to reuse energy that would otherwise be wasted as heat.
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猜猜我是誰?用腦波「想」就知道! 結合腦機介面生物辨識的智慧家庭系統
我們撰寫腦機介面程式,用低成本單電極的腦波儀讓智能車移動,實驗後發現專心度會隨著訓練而提高;在過程中看出每個人的腦波好像都不相同,所以嘗試從大量又凌亂腦波信號中萃取到四種有用的統計特徵值,再用近鄰演算法做生物辨識,正確率達到九成七以上,並實做出創新有趣具腦波解鎖應用的智慧家庭系統。此系統運用圖形的mblock、程序的C和交互式的Mathematica等程式語言,特色包含可傳訊息到手機上的緊急救難LINE通知功能和中文語音合成功能。設計出固定式的跌倒偵測和一氧化碳偵測裝置,與整合各種元件的腦波可控智能車,能自主偵測環境指標和災害意外指標並能適時提醒。我們相信唯有探索最難破解的大腦祕密,才能朝向直接用腦訊號控制和意識交流的方向前進。
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The critical role of the first discovered detached pharynges during the successful predation of Penghu Oyster Leech
澎湖牡蠣養殖受扁形動物危害嚴重但缺乏相關研究。本研究首次採集活體澎湖蚵蛭Stylochus ( Imogine ) orientalis splendida Bock, 1913進行捕食行為研究。觀察澎湖蚵蛭捕食過程分為攻擊期、捕食期和消化期,並首次報導攻擊期中發現新型的離體咽。離體咽具負趨光性( P <0.01 ** )能朝向牡蠣殼內暗處移動,使其開閉殼頻率與死亡率增加。離體咽也顯著影響文蛤死亡率 ( P <0.01** ),20條以上離體咽即可導致文蛤死亡率 60% 以上,造成文蛤外套膜萎縮,且與數量呈高度正相關 ( R2 = 0.964 ),外套膜切片顯示離體咽可導致外套膜肌肉變細且形成許多空洞。經離體咽均質和硫酸銨沉澱法萃取蛋白質後,通過SDS蛋白質電泳比較澎湖蚵蛭離體咽、咽、與其他部位的粗萃物,分離出目標蛋白質,以MALDI-TOF質譜儀分析分子量約為10 kDa。證據顯示離體咽是蚵蛭成功捕食牡蠣的重要關鍵,亦是海洋扁蟲從未被報導過的新行為。
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布拉美古塔內的「多生圓」n邊形好正!
本研究由布拉美古塔定理(Brahmagupta theory)的圓內接四邊形的布拉美古塔線,找出二種具有內切圓性質的新衍生四邊形,此特定條件下的圓內接四邊形,會呈現是等腰梯形結構。將特定條件下的圓內接四邊形推廣至特定圓內接五、六、七、八、……、等n邊形中,可發現在多組正交對角線條件下,這些特定圓內接n邊形間具有遞迴關係數量的內切圓,其半徑之間、各自的圓面積與原外接圓面積都有特殊的比例關係。上述衍生多邊形的頂點、內切圓圓心、原圓內接多邊形的對角線與其交點,這些元素間也具有多點共圓的性質。
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我們利用遞迴式求n個不同球放入k個相同箱子的方法數,得到形如巴斯卡三角的數值表,並發現在遞迴關係裡求得的數與落階乘多項式的係數恰好相同。 接著我們將形如巴斯卡三角的數值表轉換成矩陣表示,求出其反方陣,此反方陣竟然是Stirling numbers of the first kind;再將反方陣中的元素取絕對值得Stirling numbers of the second kind;Stirling numbers of the second kind表中的第n列第x行的元素,竟是將n個人分成x圈的方法數。 接著我們找出: Stirling numbers of the first kind與調和級數的關係式、Stirling numbers of the second kind與Pmn的關係式、Stirling numbers of the second kind與Cmn的關係式及Stirling numbers of the second kind與Hmn的關係式,並利用數學歸納法與gamma函數證明上述關係式;並尋找到響鈴數字與n個不同球放入k個相同箱子的方法數的連結。
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The change in NaCl crystals from cubic to octahedral~Sodium polyacrylate stabilizes the {111} face of Miller indices~
When adding 2% or 4% sodium polyacrylate as habit modifier, standard milky-white octahedral NaCl crystals grew gradually in saturated NaCl solution on the bottom of the container. [1] [2] Sodium polyacrylate is well known as a highly water-absorbable polymer with many carboxylate anions. In the case of low concentration (0.01%, 0.02%, 0.05%, 0.1% and 0.5%) sodium polyacrylate many small or microscopic crystals whose shapes were nearly octahedrons and had {111} faces were observed with an optical microscope on the bottoms of the solution containers. In low concentration sodium polyacrylate, octahedral NaCl crystals made up of electrostatically unstable {111} faces grew similarly to crystals in high concentrations of 2% or 4% NaCl. Therefore, by adding sodium polyacrylate to saturated NaCl solution, cleaved rock salt crystals in this sol were observed to find out whether or not a change in crystal morphology from cuboids of {100} faces to octahedrons of {111} faces would occur. Regardless of the sodium polyacrylate concentrations of 0.01%, 0.02%, 0.05%, 0.1%, 0.5% and 2%, all cuboid crystals changed into a pyramidal shape in which four of the side surfaces formed an equilateral triangle. When one side of each equilateral triangle face was rotated so the square face of the crystal was soaked in the NaCl sol, all crystals grew into octahedrons of high transparency. Sodium polyacrylate, even under a low concentration, caused morphological change in the NaCl crystals. Many carboxylate anions in the sodium polyacrylate attracted sodium ions and the repulsive force between the carboxylate anions became weak, excluding the water in the internal space of the polymer. We considered that the stabilizing {111} faces of gathered sodium ions attached to carboxylate anions. Chloride and sodium ions coordinated continuously to minimize the NaCl surface area, growing into an octahedral and lowering the surface energy of the NaCl crystal. [3]
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Direct reductive amination of camphor
Terpenoids are an irreplaceable class of natural products. The camphoryl group is an important moiety in the structure of chiral ligands for asymmetric synthesis catalysis or it can be used as an auxiliary group in asymmetric synthesis.[1] The usage of fenchone based molecules for asymmetric catalysis and synthesis is less common because of the difficulty of fenchone modifications due to steric hindrance. Camphor is a readily available starting molecule for the preparation of different compounds with biological activity. For example, camphor diimines demonstrate antiviral activity.[2] Fenchonyl amine-based molecules are potential therapeutic agents for the treatment of Alzheimer’s disease. Amines are a crucial class of organic compounds with multiple academic and industrial applications. There are a plethora of synthetic approaches towards amines synthesis and modifications, reductive amination being one of the most powerful and useful methods. However, the reductive amination of camphor and fenchone remains a challenge. A standard approach to reductive amination with amines other than ammonia and methylamine includes two steps: preparation of azomethines or Schiff bases in the presence of strong Lewis acids and their reduction with more or less conventional reducing agents. The synthesis of fenchonyl amines is even more challenging. There is no universal approach, and almost every manuscript reports some particular protocol different from others. In most cases, the first stage of this process requires quite harsh conditions. For example, the preparation of a Schiff base from camphor and 1-phenylethylamine requires 5-10 days of heating at 150°C.[3] Schiff bases of other primary amines could be prepared under similarly harsh conditions. Preparation of enamines is possible using titanium tetrachloride as a catalyst. The reduction also might be challenging. Sodium borohydride or sodium cyanoborohydride was described as suitable for this goal in several reports.[4] To the best of our knowledge, no papers describe any general approach for the direct reductive amination of camphor or fenchone. There is only one example of camphor direct reductive amination without an external hydrogen source using carbon monoxide as a reducing agent. This protocol is very efficient but its application is limited by the necessity of carbon monoxide and high-pressure equipment for the reaction setup.
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