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「民以食為天」。〝吃〞在我們生活中扮演重要的角色,而在這事事講求迅速、方便時代,人類真的吃得健康嗎?還是為了省時方便,而付出人類最重要資產----健康。今天小組成員想為我們人類的健康把關,我們選定了食物與我們人類接觸的媒介----免洗筷為研究的主題。先選定暢銷的六種免洗筷與我們家中不銹鋼筷子、濕竹子為對照組,實驗這些市面上長期給我們使用的免洗筷真的衛生嗎?如果我們要選用筷子,如何選擇對我們身體傷害最少筷子、哪些筷子最好不要使用?還有免洗筷可重複使用嗎?泡過筷子的水對綠豆生長有影響嗎等?我們將呈現的實驗內容,希望我們的研究主題能為我們人體健康盡心力。小組將帶大家進入實驗室,準備好了嗎?Let’s go!
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終結保麗龍污染!---利用保麗龍廢棄物處理重金屬廢水之研究
保麗龍(EPS)由於無法分解一直是環境保護的嚴重困擾。本研究是將保麗龍改質為陽離 子交換樹脂(我們稱為”保麗龍膠(EPSR)”),藉以吸附重金屬廢水中的銅離子。研究內容包括: 保麗龍膠之特性、吸附銅離子之最佳條件、保麗龍膠之再利用及最終產物之固化,企圖提供 一個解決保麗龍汙染之整套方案。 我們採用五種日常生活中常見的保麗龍廢棄物進行測試。首先將它們依下列程序處理: 丙酮溶解→硬化→打碎→與濃硫酸共煮三小時→浸於50%硫酸溶液中→沖洗→以水浸泡,將 廢棄保麗龍磺酸化為保麗龍膠。在這五種保麗龍膠之中,5 號膠(由一般家電之保麗龍襯墊所 製成)具有最佳之磺酸化比例(莫耳分率)、吸附量及吸附速率。經檢測保麗龍膠的特性之後, 發現保麗龍膠為多孔物質,具有-SO3H 的官能基,吸附的模式是先進行化學吸附,高濃度 時兼具物理吸附。 保麗龍膠對銅離子的吸附研究是以一個自動化之差動電壓檢測器進行監測,同時用電腦 精確的擷取數據。保麗龍膠達到吸附銅離子的最佳條件依次為:使用細粒的5 號保麗龍膠、 銅離子溶液的濃度為50 ppm、操作溫度為10 ℃、廢水的流速為每分鐘為 5 c.c.、以及pH 值約為4.30。多次吸附確可將金屬離子幾乎完全去除。在一次初步測試中,我們成功地將三 個自製的微型保麗龍膠儲存槽串聯,進行管柱式的多次吸附,使得高吸附率時間可以維持3.5 小時以上。 保麗龍膠達到飽和吸收後,我們再將保麗龍廢膠與由硫酸廢液和碳酸鈣製得的硫酸鈣混 合,製成黏土,可以製作造型磁鐵、分子模型等物品,達成最終產物之廢物利用,完成廢棄 保麗龍再利用之完整方案。EPS waste is a severe problem for environment due to its non-dissolvability. This research proposed a method to transfer the EPS waste to cation exchange resin, designate as EPS rubber (EPSR), which could absorb Cu-ion in wastewater. The study included the character of the EPSR, the optimal conditions for Cu-ion absorption, the reusability of the EPSR and the solidification of the final production, trying to terminate the pollution of EPS waste. Five different EPS wastes were tested. They were processed as following: solved with acetone => hardening => smashing => boiling with sulfuric acid for three hours => soaking in 50% sulfuric acid solution => rinsing => soaking with water. Then the EPS were sulfonic acidified as EPSR. Among these five EPSR, EPSR-e, which was obtained from the EPS usually used for the pad of electric appliances, exhibited the best sulfonated ratio (in mole), adsorption quantity and adsorption rate. EPSR has a porous structure with a -SO3H functional group. The mechanism of adsorption is the chemical adsorption with a physical adsorption at high concentration. The Cu-ion saturating adsorption was investigated with a automatical differential-voltage detector, enabling the data to be precisely acquired by a computer. The optimal conditions for Cu-ion adsorption were employing fine EPSR-e particles, a Cu-ionic solution of 50 ppm in concentration, a flow rate of 5 c.c. per minute and a pH of about 4.30 at 10 ℃. Multiple adsorptions could remove Cu-ions almost completely. In a preliminary test, three EPSR-e absorption cells were seriated as a column, achieving a high-absorption condition to be maintained for more than three and a half hours. After the adsorption was saturated, the final production were mixed with calcium sulfate obtained form the earlier sulfuric acid waste solution to become the clay, acomplishing a total solution for EPS waste reuse.
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我們上生物實驗課,正進行實驗3-1「 動植物細胞的比較」時,先以顯微鏡觀察水蘊草細胞的形態,再遵照步驟 3的指示,取出玻片標本,用電燈稍稍加熱,在高倍鏡下觀察,啊!奇妙的事發生了,剛才還是靜止的葉綠體,現在竟開始流動起來了,這時大家都感覺很興奮,想要探討更多關於葉綠體流動的知識,例如:為什麼葉綠體會關始流動?我們能否知道它流得有多快?是電燈泡中的光或熱來促使它流動呢?
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市面上的膠水加了硼砂水溶液之後,變成彈力球,吸引同學的眼光。究竟硼砂和膠水間,到底產生了什麼變化,這引起我們研究的動機,於是使用膠水和硼砂以及保力龍膠和硼砂,來製作彈力球,並探討不同配方所製造彈力球的彈性。由實驗結果,我們得到: 水黏土依硼砂濃度的不同,或黏著劑的不同,耐震度和彈跳高度也有所差別。當我們在製作產品時,應該考量到對於產品需求的特性,選擇適合的成份來製作。如果要做鼻涕蟲,可以用膠水和硼砂混合;如果要做彈力球,可以用保力龍膠和硼砂混合。另外我們發現保力龍膠和硼砂混合後,產生極大的耐震性,可以做為其他需要耐震產品的參考,如:可以做成耐震的杯套。
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本研究主要是利用白膠與西卡紙製作成紙橋,乾燥後以一個人的體重對紙橋作初步測試,紙橋毫髮無傷。最後將三種不同斷面形式的紙橋模型,利用萬能試驗機測得紙橋的最大承載力。將試驗所得到的數值帶入所推導的力學公式中,求得紙橋三種不同斷面形式的關係。因為桁架的原理,讓紙橋能承受較大的載重,但在我們進一步的推導公式中發現,相同截面積所得到的壓應力應該相等,可是我們實驗所得到的結果並不相等;於是我們又進一步的探討,發現原來是我們所製作的模型並不是單純的桁架構件,所以會產生彎矩力以抵抗載重,此彎矩力相當於偏心載重所產生的彎矩,於是我們將所得數值加以比較,發現當偏心距愈大,所承受的最大承載力也就愈小。不同的斷面形式有不同之極慣性矩,極慣性矩愈大所能承載之彎矩愈大,最大承載力亦愈大。
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開學的第一堂美勞課,老師要我們帶幾種不同材質的紙張及迥紋針到學校,當時我們很好奇的想知道紙張和迥紋針究竟可以做出那些有趣的玩具呢?於是就去請教老師,與老師一起發現紙蜻蜓遊戲了!
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因為水中有鹽時,經過搖動時,水中容易會產生小氣泡,礦泉水水的純度高,相較不容易產生氣泡,有氣泡有容易散去。
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颱風是台灣地區常見的天然災害之一,而台灣地區複雜的地形變化,也為颱風路徑的變化投下一個變數。根據以往的資料顯示,颱風路徑受到地形影響往往是在登陸前六小時內,而颱風對台灣地區災害最嚴重的時候往往是登陸前後三小時,也就是說要是颱風路徑受到地形影響發生偏轉,則我們只有數小時的時間來進行防災的準備。本研究主要收集1987~2001年由台灣東部登陸的台風最佳路徑圖,分別統計其颱風路徑或颱風環流過山時的變化,並分類統計各種不同颱風要素(包括颱風強度、行進速度、移入角、登陸地段等)對颱風路徑變化的影響,以做為未來預報之參考。結果顯示,台灣地形的確對颱風路徑有所影響,並使颱風在接近時偏轉,偏轉角度大多在30度以內,且偏北較偏南略多。而當颱風已偏東北方向接近時(移入角小於60度)向南偏轉較多;以偏東南方向接近時(移入角大於161度)方向偏較多,顯然地形對颱風行進有阻礙作用;而正交颱風偏轉角度也比斜交颱風小。在颱風強度部分,越強的颱風路徑偏轉角也越小,颱風過山後路徑受到導引氣流影響回到原路徑的機率較低。而影響颱風移動速度最主要的因素是導引氣流的強弱,若導引氣流受到山脈阻擋時,會使颱風移動速度減慢。而台灣各地山脈高低不同,也會使某些地區出現較特殊的台風現象。例如花蓮南部及成功地區容易誘發副低壓造成分裂路徑;台東地區因颱風容易繞山而過因此偏南機率比其他地區高等。Typhoon is a natural hazard that often occurs in Taiwan. The complex terrain of Taiwan also adds to the uncertainty to typhoon tracks. Based on past data, typhoons often show changes in their tracks within six hours before making landfall, while they produce most of their damage within three hours of the landfall. In other words, if the track of a particular typhoon was to be affected by the terrain, people have only a few hours to prepare. The study collects best tracks of a total of 145 typhoons that made landfall from the east of Taiwan from 1987 to 2001. Their tracks and changes in circulation while they moved across the Central Mountain Range are recorded, and classified according to several different elements such as strength, traveling speed, incipient angle, and landfall area. The possible influence of these elements on typhoon tracks can be applied to forecasts in the future. Results indicate that the terrain of Taiwan does have an impact on typhoon tracks, and causes typhoons to turn when they approach from the east. Turning angle in most cases is within 30°, and cases turning northward are slightly more than those turning southward. When typhoons approach Taiwan from the northeast (incipient angle 160°) they favor turning north. Also, the turning angle tends to be smaller for typhoons that approach the terrain at a right angle, and the opposite is favored when the incipient angle is more acute. This suggests that the terrain of Taiwan had a blocking and deflecting effect to typhoon tracks. For results related to typhoon strength, stronger typhoons tend to exhibit smaller turning in their tracks, but they are also less likely to return to their original direction of motion under the influence of steering flow after they leave the terrain. The most relevant factor to moving speed of typhoon is the strength of steering flow, which is slowed down if blocked by the terrain. The difference in terrain elevation can also influence the motion of typhoon and cause some rather special phenomena. For instance, a secondary low is more likely to form and result in a discontinuous track if a typhoon made landfall over southern Hwa-Lien or Cheng-kung, while a typhoon has a higher possibility to be deflected southward if it made landfall over Tai-tung, the southernmost area.
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線上教學資源
張拉整體結構實作套件設計與操作—— 在科學教育推廣上的應用設計
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由電腦與數學的相互應用談「拈」(NIM)遊戲的必勝策略
「拈」是我國民間一種流行很廣的遊戲,甚至在歐美地區亦廣為風行,由於曾在坊間數學趣談的書籍中,了解其中的一些理論架構,與電腦邏輯的思考模式頗為接近,遂興起了設計電腦程式的念頭。
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