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去年暑假,我們園子種了幾棵何首烏,有一天弟弟開學回來,抱著新課本,高興的翻開新課本,(自然第四冊,四高等植物的根莖葉)閱讀,其中有一輻插圖「牽牛花的攀緣莖」卻與我家的何首烏攀緣方向不太一樣,因此我們便請教老師,於是我們搜集、觀察、實驗尋求答案。
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在這次的防霧實驗中,我們調查了家鄉漁民常用的防霧方式、澎湖常見植物的防霧效果與探討日常常見的防霧妙方。從簡易測試與透明度分析儀的結果來看,我們發現天然防霧塗料對「玻璃」能有效的防霧,但是對「壓克力」材質的介面並沒有明顯的防霧效果;日常的化學防霧材料對兩介面都有不錯的防霧功效。
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線上教學資源
旋轉180度的紙環,從中間剪開後,會變成什麼形狀?
下圖是當快要完全剪開時,想一想會變成什麼樣的結果呢?
下圖箭頭所指的地方,各轉了180度
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青春永駐----探討地瓜葉烹飪之顏色變化
研究發現地瓜葉存放方式及料理方式會影響變色,包括變不綠、變黃及變黑;變不綠、變黃兩項和葉綠素有關;存放時接觸光線、空氣因葉綠素被葉綠素?分解而變黃,若葉子折損,因細胞內水解性單寧和酚?作用而產生褐變;水煮中細胞被破壞釋放酸性物質,使葉綠素脫鎂變橘色,添加鹽或小蘇打可穩定葉綠素,但無法阻止葉子變黑。葉子會變黑是在水煮後靜置才會出現,因此判斷是葉子中的凝縮類單寧氧化所導致,而梅納反應造成的變黑影響較小。\r 凝縮類單寧在空氣中久置會形成紅棕色沉澱;水煮時高溫加速反應,添加亞硫酸鹽類則可以抑制凝縮類單寧氧化。地瓜葉煮後變黑程度甚於其他蔬菜,是因其含有較多凝縮類單寧,而產生之變黑物質具抗氧化能力。
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〝紫外〞奇蹟,UV!---紫外線敏化酵素反應之研究
國一課本中「唾液分解澱粉」的實驗,依照課本步驟操作往往要經過半小時以上的等待時間才能獲得結果。而且唾液取自同學的口中,酵素含量及唾液中的成分因人而異,不僅實驗結果可能和預期的相去甚遠,衛生問題也令人堪憂。所以,我們進行課本中「唾液分解澱粉」實驗的改進,希望能加速反應速率並且尋找唾液酵素的替代材料。 根據觀測結果及實驗結論可知:我們的實驗證明 一、 白殼麴菌及小麥胚芽均含澱粉水解酵素可以替代唾液中的澱粉水解酵素。尤其同一活化時間的乾燥小麥胚芽產糖量遠超過白殼麴粉,所以建議利用乾燥的小麥胚芽取代唾液酵素。在使用白殼麴菌時,必須先以溫水(約35℃~40℃)浸泡活化,活化時間在50分鐘~90分鐘最佳。而使用小麥胚芽則需泡水50分鐘,經研磨後使用,對澱粉的分解效果最好。 二、 紫外線可加速酵素分解澱粉的速率,尤其發現UVA紫外線的照度對於酵素有明顯的影響。若貼近UVA紫外線燈,其催化反應效果最佳。此外,亦發現UVC的穿透力極小(無法穿透玻璃及投影片),因此照射UVC應建議直接由溶液正上方照射才不會被容器阻隔。 三、 若加入二氧化鈦當作光觸媒並且照射UVA紫外線燈,則強照度紫外線(貼近UVA紫外線燈),其效果會比只照射弱照度的紫外線更好。此外,UVC紫外線容易被容器的材質所隔離,本次UVC的測試結果無明顯的規律性,有待進一步的確認。 四、 我們所設計的可回收式光觸媒是可促進酵素反應而且是環保、省材料的生物晶片設計。 根據實驗結果,我們建議:將來在進行酵素的檢驗反應時,需要考慮紫外線對反應速率的影響,因為日常生活中紫外線的隨手可得(日光燈、省電燈泡、LED燈…)。反之也可以在以酵素催化進行各項醫療檢驗過程,藉由紫外線及光觸媒促進反應速率,來縮短檢驗時間。
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金屬是屬於帶有自由電子的物體,因此有著金屬光澤、高延展性、易導電導熱等特徵。\r 汞即為水銀,是常溫常壓下唯一的液態金屬。不銹鋼的基本元素是鐵,還有其他金屬例如:鉻、鎳、鈦、鈷等,所以不銹鋼仍然屬於金屬原料。\r 水刀不是刀,它是將水加壓至很大的壓力然後從特製的噴嘴(噴嘴直徑非常小,大約是0.1mm到0.5mm)。水通過噴嘴時便會產生一道每秒將近1000公尺的水箭,此種高速水箭可以用來切割各種非金屬物質。如在水箭中加入高硬度細沙,則可增強其切割能力,可用來切割金屬等硬度較高的物質。
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四聯原藻(Seendesmus SP.)之繁殖與抑制的研究
因某校游泳池放水後,不數日便綠色一片,且泡沫迭起,無法游泳。取該游泳池樣水,發現這些綠色大部分是四聯原藻(Scenedes - mussP .),為解決無法游泳的煩惱,乃以嘗試錯誤的探討,尋找某種物理因子或化學因子,來抑制該藻的繁殖。
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Nicholas’s project is a transforming robot, who he has named Reggie. He's about a foot tall and can transform from a biped into a vehicle and vice versa?\r Reggie has been Nick’s project for just under a year now, mainly working on him in technology classes. He operates without physical connection to anything else, so everything he needs from micro controllers to power is stored somewhere on Reggie’s body?\r Reggie is controlled through a programmable Arduino board (programmed in C++) that is connected up to a motor driver, for controlling the two driving motors and an SSC-32 servo controller for controlling the 14 servos via serial port. The Arduino uses the SSC-32 to coordinate the servos movements using pre-programmed sets of movements stored in procedures in order to complete all actions.\r All the parts were produced on a 3D CAD system to begin with, as well as the robot as a whole, although the design did change drastically over the course of its construction and now is considerably different from the original design as there were many problems and complications ranging from space to torque issues that called for a change in design.\r Most of the parts were from the servo erector set from lynx motion, although some of them were used in the way they were intended to and most of them were modified slightly. Some parts Nick manufactured himself either on a rapid prototyping machine, a lathe or milling machine and sometimes a combination of them or even high temperature soldiering?\r Currently Reggie is capable of driving and standing up and is currently radio controlled. He will eventually be capable of walking and modifications to allow him to (such as stronger leg servos) have been made to facilitate that, but it is possible more may have to be made.
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Biological control of Aphis craccivora Koch., a common pest of the cow pea Vigna unguiculata(L.)
The purpose of this project is to control the Aphis craccivora Koch. on the cow pea Vigna unguiculata (L.) by using two predators, the earwigs (black) beetle, Proeus simulans Stallan and the ladybird beetle, Micraspis discolor (F.). The experiments were carried out in the closed system in the laboratory and in the opened field with various ages of Proeus simulans Stallan and Micraspis discolor (F.) from the 1st - 4th stage of embryo to the adult form. Prior to the study in the field, the capability of the predators, Proeus simulans Stallan and Micraspis discolor (F.), that can eat the Aphis craccivora Koch. within a period of time was set up in the laboratory. The result showed that the 1st-4th stage of embryo of Micraspis discolor (F.) can eat 8.46+1.25 – 12.50+0.60, at 95% confidence, Aphis craccivora Koch. per day, while its adult can eat at the average number of 43.66 + 0.78, at 95% confidence, per day. The 1st–3rd stage of Proeus simulans Stallan embryo and the adult form can eat Aphis craccivora Koch. at the average number of 2.37+0.33 – 3.74+0.29 and 9.84+0.36, at 95% confidence, per day, respectively. This data showed that Micraspis discolor (F.) was more efficiency as predator than Proeus simulans Stallan. The insecticide activity of these two predators in the closed field (8 m x 9 m) was then determined. The number of Aphis craccivora Koch. on the plant was randomly counted everyweek for 10 weeks. It was found that the number of Aphis on the experimented and control groups were 16.20+4.30 and 2,582.00+102.40, at 95% confidence, per plant, respectively. The result support the efficiency of the two predators in controlling the pest. When the experiment was set up at the two opened field (6 m x 30 m, each field), 27.51+2.74 and 52.11+5.21, at 95% confidence, of Aphis craccivora Koch. were found on the plant of experimented and control groups, respectively, at the 10th week. The lower number of Aphis on the control plant might possilbly due to the interference from natural predators. From this study, the biological control of Aphis craccivora Koch. on the cow pea Vigna unguiculata (L.) could be achieved by using Proeus simulans Stallan and Micraspis discolor (F.). To avoid the use of chemical insecticides, biological control should be trained to farmers to help reduce the environmental problem.
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在過氧化緊迫下,粒腺體的變化與細胞凋亡的關係
因為在我們高中所學到的細胞中,粒線體是提供細胞能量的重要胞器,所以細胞凋亡時,粒線體一定也參其中。 \r 本研究發現200μM過氧化氫(H2O2)作用6小時後存活率就低於50%,而誘發細胞死亡的過程中,我們發現細胞質內的粒線體有變的越來越稀疏情況,且集中在細胞核四周的粒線體也減少許多,其結構也變的鬆散不完整。最後在細胞核出現DNA被切成小片段時,粒線體的型態及結構完全消失,粒線體的量減少到極微量,這致使細胞完全沒有能量供給而死亡。 \r 結論告訴我們細胞的死亡跟粒線體的功能喪失及形態破壞有極大的關係。
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傑克船長和他的海盜們掠奪到許多箱珍寶,每箱含有數量不等的金幣及鑽石。船員們深怕傑克船長又出什麼陰謀,一致同意讓船長任選一半的箱子拿走。\r 當然,傑克不知道金幣和鑽石的價格比,為了保證可以得到一半的利益,傑克希望他拿到的金幣和鑽石都各占一半。傑克的願望會實現嗎?\r 這個問題已用高等數學證明其解,而本研究利用初等數學的方法,除證明傑克需取的最少箱子數外,同時也能更快速的算出取法。\r 類似的結果可應用至分配災區物資等情形,或任何無法轉移、獨立的資源,如各式專長的人才、多功能的機械等,期望可對更有效的分配做出貢獻。
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