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本實驗在探討香草對蚊子的影響,用香草和一般較無氣味的雜草,來做實驗組和對照組,設計了兩大實驗。1.利用兩個箱子和一個連通管所製成的實驗箱,將植物水溶液噴灑於裝有20 隻母蚊子的箱中觀察由甲飛到乙、盤旋、垂直下降、及無反應等四種情況。得知艾草的驅蚊效果最佳,次之迷迭香、到手香,檸檬香茅最差,則其牠雜草效果不彰。2.手部實驗,將植物水溶液塗抹在手上,伸進裝有20 隻母蚊的實驗箱,停留一分鐘,觀察叮咬、停留在手上,等兩種情況。得知塗有香草的手蚊子比較少蚊子叮咬,效果為艾草最佳,次之迷迭香、到手香,最差檸檬香茅,而停留的數目,艾草最佳次之迷迭香、到手香,最差檸檬香茅,塗有雜草汁液的蚊子叮咬和停留的數目很多,幾乎沒效果。
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探討家電用品所產生的低頻電磁波是否對人體造成威脅,經過觀念的澄清後從四個方向來討論。1.將綠豆放置在不同電器用品旁;2.將綠豆放在同一種家電用品旁但是改變家電用品的數量;3.將綠豆放在家電用品旁,但是改變他們之間的距離。以觀察綠豆的發芽及生長情形。4.利用自製的防磁材料,看能不能有效隔離磁場。實驗結果發現磁場越強,綠豆的生長越不盡理想。但是在某個磁場臨界點以下,綠豆的生長將不受影響。自製的防磁材料以烤肉用鋁箔紙、鐵絲籠效果最佳,其中鐵絲籠網目越小,防磁效果越佳。
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筆者有一次,觀察洗衣機洗完、脫水後,在衣架上陰乾的衣服,發現衣服上端先乾且感覺較熱,雖然這好像是理所當然的事,但筆者認為生物課本上所說的毛細作用,應該可以讓水上升,為何一定要上端先乾?後來冬天到了,媽媽洗厚重的衣服,在最後洗清時,都有加柔軟精(如毛寶之類),筆者卻發現衣服上下幾乎是同時乾的。另外,筆者從氣象方面的書籍得知,空氣的密度會影響氣流的升降,那為何衣服下端後乾?是否跟水蒸氣含量及氣流有關,故決定著手去調查衣服是如何乾的。
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無紫外光下的抑菌-可見光奈米光觸媒研發
In this experiment, we hope to produce appropriate-sized nano particles of by using the chitin. By mixing the particles with the metal of Ti, Fe and Zn of proper proportions and therefore narrow their band gaps. Thus, the Bacteriostasis of LightPhotocatalysts could appear under the environment where the energy is lower than ultraviolet ray. We use de-acetylated chitin in three ways -- chelating agent, surfactant and protecter. Then we put a thin layer of the mixture of chitin and metal nano particles on a piece of glass, and afterwards, sintering the mixture on the glass. Next, we scan the surface of the glass with AFM(Atomic Force Microscopy) to measure its particle size. The result we got showed that the surface-roughness of the Ti-Fe nano particles was 30.642nm, the best solution of all the samples. Yet, in this experiment, Fe was not suitable. Therefore we should choose the sample of Ti-Zn mixture, which is slightly smaller in roughness. According to the result we got from the experiment, we found that, under the yellow light, the survivable strain-number ratio of the sintered Ti-Fe-Zn mixture on the glass and empty glass was 0.09±0.06. This was much better than the survivable strain-number ratio of 0.17±0.06, the result we got out from the glass of pure Ti and empty glass. From the measurement, we found that the proportion of mixture could lower the excitation energy Ti needs. Through this experiment, we hope to create a layer of film containing nano particles, and by applying it to daily-use products, we could prevent harmful bacteria. 本實驗的目的,就是希望可以利用幾丁質製作出適當粒徑大小的金屬奈米顆粒,混合適當比例的鈦、鐵、鋅金屬,使其能隙變窄,讓我們能在低於紫外光能量的光譜下,產生奈米光觸媒的抑菌效果。筆者在實驗中利用去乙醯化之幾丁質在本實驗中扮演三種角色:螯合劑、介面活性劑及保護劑,以將幾丁質與金屬奈米顆粒均勻塗抹於玻璃上,並以燒結玻璃的方式進行實驗。並且利用AFM掃描玻璃表面,確認其表面尺度,驗證的結果Ti-Fe混合比例的奈米顆粒之表面粗糙度為30.642nm,為最佳狀態,但在本實驗中Fe並不適用,故應以粗糙度僅次於Ti-Fe的Ti-Zn混合比例為主。根據實驗的結果,在綠光下,混合比例的Ti-Fe-Zn玻璃與空白玻璃的菌落數比,菌落存活率為0.09±0.06,相較於純Ti的0.17±0.06來的低,代表混合比例可降低Ti所需之激發能量。經過此實驗未來筆者希望可以以幾丁質製作出一層含奈米顆粒的薄膜,應用到各種生活用品防止細菌的危害。
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實驗室或化學工業製程所產生的廢水中常含有有毒物質,若未經處理直接排放而使河川的自淨能力無法負荷時,將對環境產生嚴重的危害。這些有毒物質包括強酸、強鹼、酚、氰化物及各種重金屬,依其污染物性質的不同,需利用各種不同的去除方法來達到預期的處理效果。近年來高分子合成技術的創新,使具有選擇性吸附的高分子型吸附劑,在去除水中有機物和重金屬上,已有突破性的發展。但此種吸附劑的價格過高,不符合經濟效益。因此,如何選擇一個適合的吸附劑,是一個值得深入研究的課題。常用的吸附劑有活性碳、粘土、矽石、兩性澱粉等。對於去除低濃度有機物或重金屬離子時,用一般處理方法較不經濟,且不易達到理想的去除效率,此時可利用吸附劑如界面活性劑或雜環族有機物等,以達到較高的去除效果。而吸附劑的選擇不但需考量吸附效果的優劣,吸附劑的來源是否容易取得,吸附反應時間的長短、飽和吸附量及吸附後廢棄物的後續處理問題等,都是必須考慮的因素。本研究利用豆渣作為吸附水溶液中重金屬的吸附劑,來探討豆渣在不同時間、不同粒徑下對水中重金屬鎘的吸附能力和去除效果。實驗結果發現:豆渣吸附時間在短時間即可達到吸附平衡,去除率在 60﹪至 75﹪左右;豆渣粒徑的大小會影響吸附能力,以 D4(0.250mm~0.061mm)效果最好,當粒徑較小時,其表面積較大所以吸附效果較好。另外,藉由 Langmuir 等溫吸附曲線可決定豆渣對鎘的最大吸附量。實驗中所使用之吸附劑(豆渣)與吸附質(重金屬-鎘)之吸附行為符合 Langmuir sorption isotherm equation,可得到一最大吸附量。
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中華民國第三十五屆中小學科學展覽-數學科評語
科展的指導老師在高中發揮了極為重要的角色,他指導學生閱讀前幾屆的重要作品,提出是當的新問題,領導研究與討論,給予類似專家的常識性建議,有些甚至成為學生的共同研究者,我們看到優秀的高中科展作品中,有許多作品背後都有一個優秀的數學老師,以本屆為例如第一名第,第二名。 指導老師在小學更是作品之母。但是小學指導老師的定位,至今仍然非常模糊。在高中由於作品水準很高,教師不易越殂代庖,但是在國小,國中指導老師很容易不由自主的陷入教的陷阱,以至於許多人認為國小指導老師就是把材料成功地教給學生。其實這是極為錯誤的看法。例如初小組肥皂泡膜角度與經濟網絡的作品,我們注意四一O四到如果教師讓學生先實測各種泡膜的角度,在得出角度都是120度的經驗歸納結果。相信兒童對於自人界的現象的數學性會有更大的驚奇,如今教師先告訴學生120度的事實,再去檢查,這種「驚奇」的驚人浪費,令我們感到非常可惜。事實上,現在已經有少數小學老師已經覺察到,如果指導老師可以更早成立研究群,更有耐心,更願意傾聽兒童在做什麼,只要找出適當的問題,兒童一樣可以有探索研究的活動。只是這種活動還需要數學教育的學者做更進一步的研究已歸納其研究活動的特質,可?科展評審的參考。當然初小和高小的差異很大。至於適當的問題雖然難找,但也不是沒有。例如初小四一O一從數字方塊到數字八卦以及高小正多邊形分割成三角形的分割總數及類型都指出值得效法的新趨勢。 國中生正處於進入文字符號運作的尷尬期,加上國中各種測試卷的反覆練習繁多,剝奪兒童從事研究的時間,一向是科展最弱的一環。這也是本組第二名從缺的原因,其實國中組無強將,反而是指導老師可以大加發揮的地方。事實上,國中生透過科展活動也可以順利甄試昇學,由於名額較少限制,更應多鼓勵學生參與。 本屆和上屆來台的美國ISFF學生作品,都和代數數論有密切關係,事實上,高中生的極限觀念的發展,比代數抽象思考的方展慢。基於此點,建議高中指導老師可以給予學生初等數論以及初等待數數論的標準教科書研讀,增強其運作的層次,代數數論的應用很多,而且也很好,如本屆的問題是說如果「n」事一個個邊皆為有禮數的直角三角形的面積則有此解可以生出無線多個有理直角三角型面積都是n。 科展研究問題的開發一向是科展師生最頭痛的問題。有一本英國空中大學教授MASON所著的「大家來數學地想」可以大大的拓展研究的想像力,數學傳播季刊,Mathematical magazine,Mathematical monthly,Mathematical Gazette,Fibonacci Quarterly,國際或亞代奧林匹克試題,Putnam試題都是傳統方法已外找材料的地方國小可從國中高中取材,但切忌獎什麼微積分代數等名堂。 另外科展老師也必須善於累績資源,以及累積自己的經驗與聲望,以吸引校內的優秀學生參與科展,本屆初小組四一O依從數字方塊到數字八卦和高中組四四一四方塊數論就是源自同一問題,但兩者的方展缺是大異其趣。四一O一大做奇偶類型經運作後演化的樹型圖,但四四一四在初步地用符號說明演化後,既一舉跳過此一過程,進入決定性的証明。其中的對比有如GORDON等數學家在不變式的工作和Hilbert一舉用一個存在性定理暫時地結束此一時期的歷史事件。另外科展老師也必須善於累積資源,以及累積自己的經驗與聲望,以吸引校內的優秀學生參與科展。
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將各種飲料倒入植物中,會有什麼結果,是這次實驗的重點。首先,我們篩選植物樣本的條件,最後選擇石竹;接著,討論出控制變因,才能決定放置植物的地點,和工作分配;第三,再討論澆灌的液體,不但要方便使用,還要性質相近,以便後續做數據分析時,能兩兩互相比較;最後,則是歸納記錄的項目,做成紀錄表。前面的實驗結束後,我們立刻整理紀錄表,做了橫向和縱向的多項數據分析,了解植物生長的好壞變化,用這些數據,對人體飲食態度當做參考,這一段是整份研究重點。第一回合縣賽結束後,再做第二回合實驗,除了全面改進,也延伸許多項目。以下將會一一列出來。
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The discovery of America
1.- Purpose of the research This Game is a new education system, where we take as reference a historical event called "The Discovery of America." The objective is to implement a new way of teaching materials using the technology developed in recent decades, where the teacher uses a modern and educational support to keep the mind of the student in ongoing activity; this will allow greater retention which gives result better understanding and more knowledge. The system is designed to model how to teach with the versatility of being a teacher to provide knowledge through a book because it contains the text outlined and summarized the history and examination by the implementation of questions that offer 4 possible answers and answering incorrectly restart the game, it forces the player to pay attention and remember information. 2. Procedures It divided the two-step strategy: 1. Define the game. The player is asked to bring the features of the game. It must recognize three: a) The technical aspects, allowing the appropriation of technological language and sometimes the understanding of the technology used to play is essential for future acquisitions; b) the commercial tab: identify which company developed the game, age or classification suggested, price, where purchased, country of origin, etc.., a review of the business tab allows to point out habits, and c) a description of the game, review of the plot, characters, history, objectives, modality, gender (role, simulation, strategy, battle, etc..) duration, etc.. This category allows the recognition of recreational preferences of the subject. 2. Thinking the game. Before, during or after the game the subject must think what you do to win or how the game unfolds. Contrary to what seems, while playing one thinks and sometimes thinks that performing other tasks and this time it is the player or the viewer understand the way it works and identify the physical or mental is used to play, trying to understand what I do but most of all how I do it, it is metacognition. 3. Data This prototype is structured in RSS: stands for Ruby Scripting System: System with Ruby Scripting for games. Object-Oriented programming "OOP" is a model used by the most programming languages, that lets you use objects and their relationships to program what will be the final application. In order to expand its use were included languages spoken in America and expanded platform for different operating systems. 4. Conclusions With this fun game is a simple way to learn the story in time, the environment and the circumstances where the player is the student of our system that shapes the teacher, book review, making it a modern and practical way to teach with the advantage of keeping the mind active during the use of our game, this allows the continued interest in the student normally lost in conventional classes.
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沖沖沖!石頭石頭我不怕~探討水的力量對大自然的災害及其防治之道
為了探究「水的力量」對大自然的影響,本組以抽水馬達、水位控制器、連通管、三通開關、大塑膠盆及電子秤等儀器,組成「水流沖力控制儀器」。實驗中:測得水位高度和水速平方成正比,而與出水口孔徑大小無關;以直立電子秤測得水的沖力與水速平方成正比;利用小石頭製成河床,並以密度與石頭相近的正立方體鋁塊受水流沖擊,推測出沖走鋁塊的最大重量和水速四次方以上成正比;利用陶土混水製成不同密度的泥漿,模擬土石流的流動情形;設計了梯形、倒梯形、河壩、倒河壩及丁壩等五種河道,測試發現河壩型河道最能減緩水流速,明顯地降低水流的沖擊力;改做不同階梯密度的減速模組,並以軟體Tracker輔助分析,得知低密度階梯減速模組,減速效果最佳。
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自從保麗龍問世以來,最先大家都用在包裝業上,做保護物品之用,接著從包裝業發展到廣告業,如今連裝飾上也採用到它。由於裝飾及廣告業都是些圖形字體,故需要鋸切,鋸切工具除了以鋼鋸條製成的鋸切刀外,亦用電熱絲來鋸切。
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在「植物的秘密生命」這本書中提到植物在電場或磁場中會生長的更好,我最近正好學到了電磁場如何產生,以及一些產生電磁場的方法,所以本研究即利用螺形管線圈來產生均勻的電磁場,並用運用安培右手定則來控制磁場產生的方向,來探討電磁場在不同條件下對實驗植物-綠豆生長的影響。本實驗使用銅質線圈纏繞鐵碗的方式,且通入不同大小電流來改變磁場的強度,以探討對實驗植物-綠豆生長的影響。本研究所得到的結果顯示:(1)綠豆在通入電流50mA 時所產生的電磁場可促使綠豆達到最好的生長效果;(2)栽培綠豆環境中所架設的電磁場較高,可使綠豆表現出較為明顯的生長速率;(3)促進綠豆的生長並不需要二十四小時都通入電流;(4)綠豆在N 極朝上的電磁場中生長的速率較S 極朝上的磁場中要快;(5)在較低溫度環境中,電磁場促進綠豆生長的效應較為顯著。;It has been mentioned that the plants will grow faster in the electronic or magnetic field in the book of “the secret life of plants”, I learned about the knowledge and methods of how to produce the electromagnetic field just now, I use the screw wire to produce electromagnetic field and control the direction by the Amplifier’s rule to investigate the growing speed of green beans under electromagnetic field in those different temperature. In this experiment, I use the wire to screwed around the ironed bowl, and make different electric current to generate different strength of electromagnetic field, the results indicate that (1) The faster growing speed will only exist in some strength of electromagnetic field, (2) The higher ironed bowls that full of screwed wire will result in the faster growing speed, (3) It will not need electromagnetic field all days, (4) The green beans will grow fast in those north magnetic pole than those in south magnetic pole, (5)The effect of electromagnetic field to increase growing speed will be significant in higher room temperature.
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Body Sway Technology:Studies on Data Correlations to Identify Elderly People Prone to Falling
It is extremely costly to care for elderly people who have suffered a serious fall. Thus, doctors welcome a device or method to identify people prone to falling, to reduce elderly health costs and enable those identified as “fallers” to take precautions. Recently, a Sound Wave Assessment (SWA) device was developed to determine if tested human subjects were prone to falling. It is based on the concept that all humans exhibit postural sway while standing stationarily. The device employs two sonar transducers, which emit and receive ultrasonic pulse signals. The first transducer is positioned on a tripod, while the second is attached to the lower back of the human subject. Each transducer emits ultrasonic modulation pulses, which are detected by the other transducer. The distance between the two transducers is calculated from the time taken for the pulses to travel from the sender to the receiver. Hence, we can measure the small displacement fluctuations of the standing human subject, both approaching and receding from a static transducer, as a function of time.
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