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科展作品檢索

電解與磁場的秘密.

金屬離子在磁場中的流動速率會略有改變,尤其是在強磁場中時,其影響更是顯著,即 【MHD 磁流動效應】,造成整體電解液中離子的流動,此流動比擴散速率佔優勢。再利用「磁 矩」具有向量性質,探討不同金屬離子(Na+、K+、Fe3+、Al3+、Mg2+)及MnO4 -在磁場角度 相同但強度不同的情況下;及磁場角度不同但強度相同的情況下,對電解速率的影響。 經實驗發現有以下結論: 一、由法拉第電解第一定律出發,加以實驗數據分析,可推導出一關係式: 電解速率Rρ= k ×∫〈∣H 向量∣×∣cosθ∣〉×∣E 向量∣ (k 單位:g / C˙weber˙s) 二、電解效率隨價數增高而增快。 三、較強的電解質,其對磁場的感應也越大,如果就同一族而言,往 下其活性越強,對磁場的感應也越強。 The flowing rate of Metal ion changes slightly in magnetic field. This influence is especially remarkable while the magnetic force is very strong, that’s【MHD (magneto Hydrodynamic Effect ), which gives rise to ionic flowing all over the electrolyte. This flowing rate is superior to expanding rate. Further, basing on the magnetic torque ’s vector trait, this research studies how electrolysis velocity affects different metal ions (Na+、K+、Fe3+、Al3+、Mg2+) and MnO4 - under following situations: Some results are found through the experiment. 1. Begin with Farad Electrolysis First Law, and take the experimental analysis into account, then a relative formula comes out as bellow. Electrolysis Rate Rρ= k ×∫〈∣H∣×∣cosθ∣〉×∣E∣ (k:g / C˙weber˙s) 2. Electrolysis efficiency accelerates by the increasing price amount. 3. Active electrolytes get strong response to the magnetic field. For the same group, the more active the electrolytes are, the stronger it responds to magnetic filed.

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電子流動的真相

單獨將銅片放在酸性的電解質溶液中,不會產生氫氣,但若我們把本身在酸性溶液中會產生氫氣的金屬與銅片接觸,兩端都會產生氫氣,例如:鋅片與銅接觸後,除了鋅片上本來就會產生氫氣外,銅片上也會產生氫氣,這證明鋅銅片間有電子傳遞,比較鋅片與銅片產生的氫氣體積,推算出鋅銅片間電子傳遞的比例,討論不同變因造成的影響。經由這個實驗,我們得知更好的方法詮釋陰極保護法,另一方面,也能延伸至如何得到一個有更高效能的電池,或是發展出不需外加電壓的電鍍(浸鍍)技術。

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本土天「蝗」傳奇~台灣大蝗蟲生活史及生態習性的研究

台灣大蝗在交配時警覺性降低,♀蝗會背著♂蝗跳到遠處,但不會飛,肚子餓時會進食,\r 但♂蝗不會。交配後♀蝗會選擇土質堅實、植被稀疏、表土層水分適當、有相當溫度、地勢\r 向陽的土壤中產卵。卵隔年春天孵化,爬出土的同時也脫去一層皮。若蟲共分6 齡,齡期越\r 大,觸角節數愈多,翅芽愈大,前胸背板上後緣也越往後延伸。\r 8 月中旬成蟲開始在馬路上出現,初期♀蝗較多,9 月底野外路旁只能看到♂蝗。♂成蟲\r 較會出現在樹上或草上而♀成蟲較會出現在路上或牆上。因為台灣南部冬天氣溫帄均都達20\r ℃以上,比北部高4℃,於是休眠中的卵提早孵化,因此整年南部皆可發現台灣大蝗的蹤跡。\r 大蝗取食主要是靠嗅覺。白天牠在休息或飛行時都會有趨光性但無趨熱性,在夜晚則沒\r 有趨性。後腿除了防衛與跳躍外,還有游泳、翻身、起飛、帄衡、踢開身上的小蟲與糞便等\r 功能。

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反射投影機演示物理實驗

(一)反射投影機( ovorhead projector 簡稱 OHP)在中學是很普 及的設備,但平常使用率並不高;一方面由於使用法的書籍太少 ,主要缺乏互相研習觀摩的機會,因此常使此視聽教學媒體束之鐵櫃中,十分可惜。在國內除了彰化教育學院於四年前大力推行透明片的製作;及作者於民國六十七年出版的第一期 "中華民國物理教育期刊"發表六件配合OHP的實驗器材外,在所有的科教刊物均未見提過。鄱閱國內二十年來的科學展覽專輯,除了十七、十八、二十屆由作者發表八件有關OHP 的作品而獲獎外(均第一名),也沒有其他得獎記錄”在美日的科教期刊上,從1959 年" American Journal of Phyoics "開始發表迄今仍有四種科教期刊不斷地發表新創作,日本的"科學の實驗"則作類似的翻譯工作。在書籍方面除了 1962 年Walter Eppenstein 出版"The Overhead projector in the physics Iecture 。”一一配合OHP 的實驗器材25件外,其他書籍都著重於透明片的製作及使用法;此書在美國已絕版,幸賴同學從 Washington Univorsity Physics Librory 影印回來。(二)作者於民國六十六年初參加彰化教育學院一個透明片製作講習會後,開始對OHP 的使用發生興趣,在平常教學活動中,充份地使用 OHP,且不斷地自行研製能配合OHP 演示的教具,並且從圖書館的期刊蒐集有關資料,再從期刊上的參考文獻上蒐集更多的參考文獻,至今已有五年,有關文獻已有五年;前年參加全國科展,陳館長對科學資料的蒐集整理參加科展非常鼓勵,因此花了近兩年的時間將之整理成冊。

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那一個變因影響流動的速度

上勞作課時,老師要全班同學收集各種空罐子。有奶粉罐子、陣酒總子、蘆筍汁罐子、味全花瓜罐子、奶油罐子... 等。下課時,忽然滑梯那邊傳來「加油!加油!」之聲。原來他們把空罐子從滑梯上滾下來,比比看哪一個罐子滾得最快。每個人都認為自己的罐子滾的最快,爭吵不休,只有請老師來栽判。

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線上教學資源

蜘蛛都是有毒的嗎?

所有的蜘蛛都有毒? 蜘蛛是純肉食性的動物,主要的食物是昆蟲,在捕食之前為了控制獵物的行動,咬一口後,便從大顎鉤狀的銳牙末端開口注入含有麻痺性成分及消化酵素的唾液,將獵物痲痺後,把牠的身體組織消化為液狀,再慢慢地吸食獵物的汁液,這種消化方法叫做口外消化。我們所說的蜘蛛毒液就是蜘蛛的唾液。 嚴格地說,所有的蜘蛛都有毒,只是毒性有強有弱。蜘蛛攻擊捕獵的主要對象是昆蟲,牠們唾液裡的毒性對昆蟲有致命性的效果,但對體重比昆蟲大上萬倍的人來,蜘蛛的毒通常都不是劇毒,被牠咬一口就像被蚊子叮一下。例如體長約4公分的高腳蛛在室內走動,看起來很嚇人,其實牠幾乎不咬人,萬一被牠咬一口,也只有輕微的麻木感和痛覺。 哪些蜘蛛的毒性較強? 在近4萬種蜘蛛中,還是有少數蜘蛛毒性較強,其中對人類有害的頂多20種。 廣泛分佈於美國及澳洲地區的黑寡婦,體長雖只有1公分,卻是有名的毒蛛,因為漆黑的腹部上有沙漏狀的紅色斑紋,交尾時經常咬食個子比牠小許多的雄蜘,而被叫做黑寡婦。牠的唾液中含有可作用於脊椎的神經毒。在1960年至1973年間,美國就有1726件被黑寡婦咬的病例,其中55人宣告不治。 有一種黃色的螯蜘蛛,體長約1公分,母蛛利用蘆葦等禾本科植物的葉片建造肉粽狀的育兒室,不小心被牠咬一口相當地痛。牠的毒性相當高,可殺死一隻小白鼠,但不會危害人的性命。 分佈於澳洲的雪梨上戶蛛,雌雄皆有2.5-3.5公分的體長,都具攻擊性,由於身體較大型,分泌的毒液量也多,雄蛛的毒性是雌蛛的三倍。 以寵物蜘蛛而有名的捕鳥蛛,大型者約有7-8公分,雖然傳說牠會捕捉小鳥為食,但至今沒有得到證實,牠不會主動攻擊包括人在內的大型動物,避免浪費自己的毒液。 談到毒蜘蛛,不能不提在中世紀歐洲被認為含有劇毒的塔蘭圖拉蛛,相傳被牠咬後必須配合音樂狂舞,直到累倒為止,才能解毒。其實牠是對人體根本不會發揮毒性的一種狼蛛。

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科展作品檢索

Generalized Quantum Tic-Tac-Toe

Early physicists such as Newton thought that all objects have definite positions. For example, they thought that an apple is either inside a fruit bowl, or outside of it. The advent of quantum physics in the early 20th century proved this viewpoint wrong. There is an uncertainty in the position of any object; we can find a set of possible locations where the object might be. This concept was termed superposition. Quantum tic-tac-toe (QT3) elegantly extends the popular game of tic-tac-toe by adding this quantum physics concept of superposition. Each turn, 1 piece is simultaneously played into 2 distinct squares of a 3-by-3 grid. Eventually, however, every piece will occupy exactly one square, like in tic-tac-toe. Yet, despite this intriguing addition, not much research has been done on the game. Hence in this paper we explore the game in terms of extension, analysis and solution. Firstly, we note that the quantum extension proposed by Alan Goff in QT3 is incomplete. In reality, there can be more than 2 possible locations for any object. Unfortunately, the QT3 game rules do not allow for this extension. Thus we non-trivially generalize the game (GQT3) by proposing a new set of rules. We show that the original QT3 is a subset of GQT3 and prove that our generalized game can always be successfully played from start to finish in a finite number of moves. Then, we begin our analysis of GQT3. Firstly, we investigate the game tree complexity, state space complexity and computational complexity of the game; indicators of how complicated the game is. Notably, we find here that QT3 has a total of about 18 trillion possible games, which is substantially higher than tic-tac-toe’s 400 thousand. Then we examine the Nash Equilibrium of the game; the result if two ‘Gods’ play the game against each other. We find that in this scenario, the first player will win by 0.5 points. To make the game fairer, we suggest minor variations on the scoring, which make the Nash Equilibrium a draw. Note that standard methods to analyze all of these would take at least a year, but we bring down the time to about a minute using symmetry considerations and other optimizations. Finally, we extend our programs into an artificial intelligence that is a perfect solution to the game. We then supplement this with a utility function to make the run-time performance pragmatic for more time-consuming versions of GQT3. Ultimately, GQT3 is a challenging and unique game with myriads of exploration possibilities; we have only scratched the surface here.

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旋轉月相盤之試作

國小自然科學課程,有關天文方面之教材,其教學過程是讓兒童從實際的觀測與記錄中,根據所發現的規則性變化,歸納說明天體運行的概念。尤以月亮之觀測,自三年級起做長期的觀察記錄,兒童從記錄資料中發現月形和位置的規則性變化,可以用來預測時間,最後歸納說明月球週而復始的在太空裹,行有規則性的運動,激發兒童探究宇宙奧秘的濃厚興趣。筆者透過輔導教師研習會及教學觀摩會,發現諸多教師對於指導學生“觀測月亮”有不少困難,因此,筆者搜集有關資料,繪製成“旋轉月相盤”以供教學參考。

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Investigation on traditional medicine from plants in Namibia

My project is about investigation on traditional medicines in\r Namibia. This is all about plants and different herbs that different\r people in Namibia use for medicinal purposes. The objective of this\r project is to inform the world of how valuable nature is and how we can\r try to conserve nature’s treasure so that valuable knowledge cannot pass\r away with olden experienced herbalists. Understandably the enquiry\r into indigenous medicinal herbs arose from the need to expand the\r possibilities of ones own medical practice. It was very important for me\r to satisfy our farmer’s thirst for knowledge, which is what I want to do\r with the rest of the world.\r In this project I have included most but not all of the plants that we\r use in Namibia for medicinal purposes. Seeing that some of these plants\r do not grow in certain parts of the country, I have also tried to clone it in\r other parts of the country. I have also made a powder from one of the\r plant’s leaves and tested it on several people within the country.\r To conclude my findings and experiments I would like to say, let us\r try to take these precious knowledge left for us from our ancestors and\r maybe one day in the future we might need it in some ways.

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「連續自然數的乘方和定理」如何被我發現

喬治.波利亞(George Polya)所善「數學研究法」( Mathematics and Plausible Reasoning)給我很多的啟示與靈感。書中引數學家高斯(Gauss)的話說:「數論中有料想不到的好運氣,藉歸納法挖掘到最優美的新真理。」

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當急驚風遇上「玻璃片」-以簡單原理研製便宜準確風速計

本專題研究之目的,在於運用簡單的原理自製出準確、廉價、適用於低風速範圍的風速計;方法是藉由將一連接轉軸的玻璃片迎風,探討迎風時,玻璃片偏轉夾角和風速之間的關係。實驗過程中同時發展出可以用馬達旋臂的裝置與v=rω的原理,產生穩定可計算風速的環境。研究結果發現:在低風速的環境下,θ 範圍小時玻璃片與地夾角和風速大略成正比的關係,所以我們可以得到近似式” v≒aθ+b”,參數(a,b)依玻璃片而定。另外θ 範圍大時,我們可以使用二次逼近曲線的方程式與內插法來作角度與風速的對應。藉由控制玻璃片的厚度、質量與形狀,我們可以製造出相對應風速範圍的風速計。The purpose of our research is to use easy theorems to make accurate and inexpensive anemometer which is available in low wind velocity. To make such anemometers, we made a piece of glass, which was connected to a axle, to face wind; then, we could figure out the corresponding relation between wind speed and the angle created by the original and the resulting positions of the piece of glass. While we were experimenting, we found that we could make a steady-wind-speed environment by using motors, sticks, and the theorem ”v=rω”. The research showed that the angle created by the original and the resulting positions of the piece of glass and wind speed are in direct proportion in low wind velocity in small θ range. Consequently, we\r can derive the formula ” v≒aθ+b” , for each piece of glass (a,b) can be different. In addition, when in bigger θ range, we can use quadratic approximate equation and interpolation to describe the corresponding relation between the angle and wind speed. By adjusting the thickness, mass , and the shape of the glass, we can make anemometers corresponding to different wind velocity ranges.

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黑心竹筷現形記

在新聞報導中指出一般免洗筷子中大都有殘留二氧化硫,而二氧化硫可能導致過敏或氣喘病。本實驗主要是利用國中理化實驗室中常見的藥劑,找出檢驗竹筷子中的二氧化硫的簡便的方法。我們把竹筷中二氧化硫的檢測分為定性與定量分析兩部分。在定性分析實驗過程中,我們發現氯化鋇雖然可使亞硫酸根產生白色沉澱,但沉澱的現象不是很顯著。因此在加氯化鋇之前先加入過氧化氫,使亞硫酸根氧化成為硫酸根,可使產生硫酸鋇沉澱效果更顯著。而定量分析部分,經過多次的試驗,我們改進滴定的方法。首先降低碘標準液濃度,並利用注射針筒與點滴用的軟針來進行滴定,使得微量的二氧化硫可以被檢測與分辨出來。而根據實驗結果,我們發現所收集的衛生筷,只有木質衛生筷無二氧化硫殘留。而從定量實驗中可發現浸泡三小時或煮沸應該有助於去除竹筷的二氧化硫殘留。

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