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同是一家「氫」?-鹼性的酸式鹽陰離子溶液與活性金屬的氧化還原反應探討
在氧化還原反應中,活潑金屬(Mg、Al、Zn、Fe)在酸性溶液中才能產生H2的反應是既有的認知自然現象,但在pH>7的溶液中沒有傳統氧化劑的存在下,活性金屬仍會反應產生H2,活潑金屬有可能會與酸式鹽鹼性陰離子(HPO42-、HCO3-)或這些溶液中的氫離子反應產生氫氣,我們試著用HPO42-、HCO3兩種呈鹼性的陰離子與活潑金屬反應,觀察其反應狀況,礙於實驗設備,我們藉著測其短時間內的氫氣體積量,檢驗此三種陰離子與活潑金屬的反應性,另外,我們亦試驗單純的H+(HCl)、OH-(NaOH)溶液與活潑金屬反應作為比較及空白實驗。由實驗結果顯示HPO42-、HCO3-與Mg的反應狀況良好,可持續的產生氫氣,HPO42-、HCO3-與Al、Zn、Fe反應狀況極差,幾乎無法產生H2,唯Fe表面有少量的氫氣產生。實驗顯示HPO42-、HCO3-有可以與Mg產生H2的反應活性,且猜測兩者與水中微量氫離子相比,更容易附著在金屬上,所以反應進行的主要原因是陰離子的存在。
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看起來相當不起眼的六角拼圖,不知為何會在教室引起騷動,原只是想挑戰拼組的那份成就感,沒想到定心去探索竟別有洞天。六角拼圖在經過數字化後,其秘密就明朗多了,原本單純的拼圖,經過數字對應轉化後,又可生成更多組數列拼圖。為了縮短拼組時間及判斷時的手感,我們想出了創意的快速拼組輔助道具~長條數列棒來替代六角模式,搭配尋得的一些規律,能有效縮短試誤次數,在很短的時間即可判斷出有解、有幾組解或無解,同時從很多線索的歸納整理中,我們也發現了單組解與多組解拼圖轉換之關鍵。爾後又突發奇想的思考規則改變之可行性與實用性,深入探討同時符合兩種規則之有效拼圖組的設計規律,最後衍生出”雙拼六角板”以及”六角棋”的益智遊戲,做為可推廣的數學益智教具,深具趣味性與挑戰性,真是令人雀躍。
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基隆河三貂嶺至南港段沿岸植物群落調查
經由研究過程,進一步認識本地鄉土資源,祈於日後教學中,能配合自然科學課程之精神,以兒童熟悉的鄉土資源為教材,提高學習興趣,增進教學效果。
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皮膚癌的成因有許多,但是一個很大的因素來自於太陽光中紫外線的照射,如果接受到紫外線的照射量較多,皮膚產生此病變的機率會較高。在大氣中有氣體可以吸收紫外線,那就是臭氧,在大氣層裡面高度20~30公里處有臭氧層,這些臭氧分子會吸收紫外線,讓我們避免被大量紫外線照射,事實上,氧氣也會吸收紫外線,只是跟臭氧吸收的是不同波長的紫外線。
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媽媽常常買一些蕃薯回來準備作菜,但是有的蕃薯放久了以後,就開始發芽;蕃薯的儲藏根和馬鈴薯的儲藏莖不同,其表面並沒有芽眼,但仍然可以在許多地方冒出不定芽或不定根來;國中生物課本曾經學過,成熟的根和莖在外觀及內部構造上有很大的不同,為了探究其原因,我便以蕃薯的儲藏根為材料,希望知道其在儲藏根上長不定芽或不定根的部位是否有所不同,以及影響其長出不定芽或不定根的外在及內部的因素。
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國中生物課本第七章蛋的構造,使我們知道蛋的性狀都不相同,蛋的外觀及內部的色澤、凝固強度差異極大。我們吃的酸蛋、皮蛋、水煮蛋、溫泉蛋,是否受到溫度、酸鹼性的影響?是否蛋浸泡不同酸鹼溶液及加熱會影響蛋黃、蛋白的色澤及凝固性?激起了我們的興趣而去深入研究探討。
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以自製的反應儀器研究鹽類對雙氧水分解反應的影響
本研究是以自製的反應儀器全程監控雙氧水加入不同的三價鐵鹽中,伴隨著氧化還原及催化分解產生氧氣的全部過程,其設計流程如下: 反應器→排水集器法→虎克定律→滑尺感測→A/D電路→電腦將雙氧水分解出的氧氣,利用集水桶收集,集水桶的重量向下拉動滑尺,使其感應部分通過光遮斷器,藉由A/D 電路,電腦收集電壓與時間的數據,再配合校準線的資料繪出反應速率與時間的關係圖。研究結果顯示三價鐵鹽中,Fe(NO3)3 和FeCl3 的反應情況較類似,氧氣的產生很快達最高速率,其最大反應速率值約在0.4ml/s-0.6ml/s 上下,但反應也很快完成。Fe2(SO4)3 的反應情況較溫和平緩,慢慢提升其反應速率,且其最大反應速率也較小,約在0.1ml/s-0.2ml/s 上下。藉此研究結果,若要利用雙氧水的氧化力應用於工業的污水處理上,Fe(NO3)3 和FeCl3 較適於速效性(如旺季,訂單大量,產生廢水量較大之行業); Fe2(SO4)3 較適於長效性(如淡季時,不景氣,產生廢水量較少較緩之行業)。若鐵生成穩定錯離子後,其反應速率皆較慢,實驗結果其最大反應速率值約在 0.01ml/s-0.02ml/s 上下,速率比非錯鹽的鐵鹽慢了十倍多。其中Fe(CN)63-,圖形與FeCl3類似,其餘其反應速率較近於定值,可將此結果應用於日常生活中需較固定氧氣產生,而其速率不必很大處(如水族箱之氧氣供應,燃料電池之氧氣供應)。
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我最寫歡看雲,夏天的時候,常能見到潔白的雲朵,像花椰菜般,朵朵飄在蔚藍的天空中,天邊有時也會出現一座座又高又壯的大山,真是令人嘆為觀止。冬天的時候,卻常見到堆成一整片的雲,像一塊厚鐵,有時雖然晴朗,卻再也找不到耶一座一座的大山了,我感到很疑惑,為什麼夏天和冬天的雲會有不同?難道一年四季的雲都不一樣嗎?於是我們幾個好友就一起觀察研究,想看看一年四季的雲究竟有什麼不同?
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Image Compression Program Using Different Fractal Formulas
File compression has become a very important tool in the technology field because it allows faster data transfer rates over the internet and decreased file size on data disks. File compression aims to reduce file size while still retaining the quality of the file. Lossy file compression methods are not very efficient because the compressed files end up losing more data than what is usually intended causing a considerable loss in quality. Lossless file compression methods, on the other hand, take time to process since they require decompression to retrieve the original file. In this study, a lossless algorithm which does no require decompression was created. The resulting Fractal File Compression (FFC) algorithm contains two parts, the IFS algorithm and the Huffman Tree generator. Both algorithms were created using Java language and JCreator. The finished program was tested on an image file with 2542 x 1944 pixels dimensions. The image file was compressed using JPEG, BMP, PNG and FFC formats. For each method, the image file was compressed at three different resolution settings; low, medium and high. All the compressed images were then viewed under 500% zoom using Adobe Photoshop CS2. In an area of 40 by 40 pixels, the number of distinct boxes, which served as a measurement of image quality, was determined. Compressed images for JPEG, BMP, and PNG for both the low and medium settings have low image qualities, while the fractally-compressed images have a high image quality. For the high resolution setting, both JPG and fractally-compressed images have Page 2 of 2 high qualities while BMP and PNG still have low qualities. Based on the measurements obtained from the box-counting method and the file sizes, the absolute image quality for each compressed image was calculated. The absolute image qualities of the compressed images used for each setting were then compared. Coupled with large file size and small pixels per area count, the conventional methods have lower absolute image quality than the images compressed using the FFC method. This was true for the low and medium settings, however, JPG compression has a higher absolute image quality than the fractally-compressed images. This meant that JPG compression is more efficient than fractal compression when an image has a high resolution. The resulting FFC algorithm is lossless since it uses pattern searches and replacements in order to decrease the file size. To make the program more suitable for high resolution images, the FFC algorithm may be modified. Most of the changes in the FFC algorithm should be done in the IFS generator. High resolution images can be compressed fully if the pattern that was used for compression is more representative, but even shorter. A more representative bit pattern would create a high quality, high resolution image with a smaller file size.
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搶"風"頭---彎曲吊扇與風力的探討
扇葉彎曲,就像一個人病了,我們能做的不只是將它丟棄而是去了解什麼原因讓它變成這樣!而原因就是”濕氣”在作怪;而扇葉的新材料太重時則阻力變大、易下垂,太輕則扇葉易變形、晃動劇烈,太寬、太窄時都有不同的變化、都會影響吊扇的風力。並利用『分貝儀』來測量扇葉風力(噪音)大小,結果連微風也可精準的測出。補救扇葉方法:泡水後的扇葉是鬆垮的。但再浸泡樹酯並緊壓、乾燥後,舊扇葉的強度有明顯的復元變好。吊扇與天花板的距離:發現太近時吸力變大、氣流變強、噪音增大,風力卻變小。當大家在倡導環保時,我們也希望不要因為吊扇老舊了就將它整個丟棄,應該可以發揮新的創意,將環保與實驗結合起來,作更有意義的應用。
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橙五線陸生渦蟲(Bipaliumaurantiacus)廣頭部彎曲功能之探討
本研究經實驗橙五線陸生渦蟲(Bipalium aurantiacus)發現,其廣頭部有不同的彎曲方式,分別為波浪形、左右形及上下形。在探測獵物時,其廣頭部使用波浪形彎曲;探測獵物味道、攻擊時,使用左右形;探測環境光度時,則使用上下形。在探測時,不同彎曲方式接近不同感應物的頻率並不相同。此外,廣頭部在探測時會有擴大的情形,進一步推測感覺神經分布情形,並運用生物檢測(Bioassay)驗證。經觀察不同種廣頭地科陸生渦蟲,發現廣頭部彎曲情形無太大差異,且無廣頭部之陸生渦蟲廣頭部敏感度會下降,由此知廣頭部對陸生渦蟲的重要性。前人對渦蟲的研究,多針對水生渦蟲,對陸生渦蟲的著墨較少,且僅是初步研究,經本研究,將對橙五線陸生渦蟲的廣頭部有更進一步了解。
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PALF As Alternative In Novelty Composite
Pineapple leaf fiber (PALF) which is rich in cellulose, abundantly available, relatively inexpensive, low density, nonabrasive nature, high filling level possible, low energy consumption, high specific properties, biodegradability and has the potential for polymer reinforcement. The utilization of pineapple leaf fiber (PALF) as reinforcements in thermoplastic form for developing low cost and lightweight composites Pineapple leaf fibre (PALF) is one of them that have also good potential as reinforcement in thermoplastic composite. The objective our research is to characterize PALF and to investigate the effect of fibre treatment on the mechanical properties of PALF reinforced polypropylene (PP) composite PALF was obtained from pineapple plantation after the harvesting. The we dry the PALF to remove the water. Next step is grind the PALF into small particle. Both PP and PALF were compounded using internal mixer machine prior to compression moulding via hot press machine to form a sheet. After forming the composite sheet, samples were prepared for tensile test (ASTM D638), flexural test (ASTM D790) and impact test (ASTM D256).
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