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國中課本第五冊第 141 頁 5-4 練習第六題,我國民間相傳有下列五邊形的近似作法”九五頂五九,八五分兩邊”經過幾次的畫法,均發現並非真正五邊形,其誤差雖極小,仍困擾著我們的求知欲,因而請教於老師。
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台灣地區平均在一年中會產生一、兩個龍捲風,雖然其次數不多,然而龍捲風是短時間所生破壞程度最大的風暴系統。本實驗藉由模擬龍捲風的行程,探討其生成的因素。本實驗以『上方風扇』:模擬真實龍捲風的低壓中心,控制電壓的大小以影響氣流上升速率的快慢、『下方風扇』:模擬風切,控制電壓的大小與仰角以影響氣流的水平向、鉛直向大小、『口徑』:利用上方口徑大小以控制氣流鉛直方向上升速率與形成之暴風半徑大小、『高度』:利用高度的高低以控制氣流鉛直方向上升速率。結論:(1)上升範圍(口徑)越小,暴風半徑越小(2)上升氣流(上方風扇)越快,暴風半徑越小(3)風切(下方風扇)風速越大,暴風半徑越小(4)對流高度越低,暴風半徑越小
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高溫是引擎、電器、機件、電路、管路加速劣化,縮短使用壽命的最大殺手。有鑒於汽車引擎高速、長時間運轉後,其溫度仍很高,引擎熄火後,引擎高溫無法散去將使得引擎室猶如烤箱,在如此高溫不通風的環境下,常導致許多線路及電器零件的加速劣化,縮短其使用壽命。例如:一般使用3~5 年後之車輛,經常會遇到引擎狀況雖然不錯,但總常會有引擎周圍電器、零件、線路、管路等,陸續出問題,而被迫進廠檢查維修,造成許多的不便及時間上、金錢上的損失。
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在這個研究中,我們利用自己設計的「黃金比例」風箏,在實驗室中控制風力的大小,來研究在同樣情況下,什麼樣的風箏面會飛得比較好。然後再研究加上不同的尾墜以後,風箏飛行的情況會不會比較好。我們進行了尾墜數量、長短、材質、位置、側墜和尾墜比例的實驗。最後研究風箏面的提線變化,對放飛風箏的影響。研究結果發現:風箏面的材質要使用比較輕而且柔軟的材質;尾墜的數量、重量、長短都要適合風箏面的大小;提線最好是兩邊一樣長的,在放飛或是風箏飛行的時候,比較能夠保持平衡。我們將自己研究的模型風箏放大三倍以後,實際到戶外放飛,結果飛行的狀況十分良好,風箏可以飛得又高又遠,而且很久都不會掉落。所以證明我們所研究出來的風箏,符合了我們的「好風箏」的標準,可以成為小朋友自己在家製作的休閒玩具。
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Synthesis of Polymer Material and its Decomposing Processes Because plastic cannot be decomposed naturally by itself, therefore, additives needed to be added to facile the decomposing process. Let us choose one common material: thermoformed Nylon 66. During the formation process, addition of glucose powder and monosaccharide polymerized will result in yielding the products of methyl cellulose, soluble starch and agar powder. Observe whether adding additives would allow changes to occur structurally, or would the elasticity be improved when exist in a linear state, or even it would form a better pH resistance property. According to the experiments, when Nylon 66 contains methyl cellulose, it can sustain the highest tension. Its coefficient of elasticity is 2 times as large as the original one. In terms of the data, we can also observe that when Nylon66 contains soluble starch, it has the lowest ability to sustain tension. Besides, it has the lowest coefficient of elasticity. And when Nylon 66 contains cellulose, it has the highest rate in the process of decomposing.As we look at the surface of polymers under 400 diameters, we can observe that the Nylon 66 with agar powder has some filiferous substance. But we have not confirmed what the matter is. 由於塑膠不能在自然情況下順利分解,所以我們在塑膠中添加其他成分使塑膠可以較易 分解。我們選定常見的塑膠—熱塑性的耐綸-66。在聚合物的製作過程中添加葡萄糖、澱粉、 洋菜粉末以及甲基纖維素,並觀察加入添加物的塑膠在結構上是否有變化?其塑膠在線型時 之張力是否有增強?耐酸鹼性是否有變化?由實驗結果我們可以得知含有甲基纖維素之耐綸 -66 所能承受之張力強度最高,且其彈性係數也比無添加物之耐綸-66 高出近2 倍;而含可溶 性澱粉之耐綸-66 所能承受之張力最小,且彈性係數也最低。此外,進行生物分解的實驗可發 現,含葡萄糖的耐綸-66 分解的速率最快。使用400 倍的光學顯微鏡可發現含有洋菜粉末的耐 綸-66 表面與其他耐綸-66 複合材料差異較大,值得進一步研究。
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本校擁有設備精良的天體望遠鏡及天文臺,且嘉義地區晴天日數較多,非常適合做太陽黑子的觀測。自入學後,即參加天文社,在師長指導下,有計劃的從事太陽黑子觀測活動。部份作者即將高中畢業,謹將一年多的觀測結果發表,希望學者專家指教。
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在我們學校的植物教材園及附近的田園裡,遍植了數十棵的白千層。它的數皮奇特,灰白軟綿綿而有彈性,般可惜的是樹皮處處裂痕,層層剝落,永無止境。這種奇怪的現象,引起同學們的喜愛和好奇。有幾位特別好奇的同學,將快脫落的灰白樹皮剝下來,給大家仔細觀察,果然發現樹皮的組織,重重疊疊,層復一層,與眾不同。難怪它的名字叫白千層,名符其實,真是奇怪的樹皮!
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我們希望能製作長時間不會破掉的肥皂泡泡,使得垂直懸掛的肥皂薄膜能一直流動到很薄的狀態 --- 希望能薄到幾十個奈米。然後從肥皂薄膜的光學干涉條紋變化,測量其厚度,並且研究肥皂薄膜流動的現象。研究結果顯示:我們可以作出能持續流動60秒以上不會破掉的肥皂薄膜,其中可以準確量測的最薄處大約117奈米,由外插法得出其頂端的厚度小於50奈米,用測量電阻的方法得出該處厚度大約為15奈米。而且我們還發現在薄膜厚度大於350 nm時,薄膜的電阻和厚度成很像反比的線性關係,但是在薄膜厚度小於200 nm時,薄膜的電阻和厚度的平方成反比。我們也由各層干涉條紋的流動,了解了肥皂薄膜流動的過程,並且觀察到可能是液晶層狀流動的現象。
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流行病學資料顯示,近年來口腔癌發生率明顯增加。本研究之目的是探討口腔黏膜細胞微核發生頻率及彗星分析法之基因傷害指標是否與菸、酒、檳榔暴露有關,以及是否可以看到菸、酒、檳榔之交互作用。 研究對象為桃園地區山地鄉之民眾,利用問卷收集個人之菸、酒、檳榔及干擾因子之暴露資料,再採集樣本之口腔黏膜細胞及血液樣本,進行基因傷害評估。 結果顯示,口腔黏膜之微核發生率與檳榔之暴露相關性最大,可以解釋12.6%;然而,彗星尾部動量和尾部長度則以香菸暴露解釋力最大;同時,檳榔與香菸的基因傷害交互作用似乎存在。因此我們認為,口腔黏膜細胞之微核發生頻率對於檳榔暴露者應是不錯的基因傷害指標,而香菸暴露則以彗星分析法之指標較為敏感。 ;Epidemiological studies showed that the incidence of oral cancer increased significantly in recent years. The purpose of this study is to evaluate the genotoxicity of cigarette smoke, alcohol and betel quid use as well as the. interaction effect between these three risk factors. The study subjects were selected from residents lived in a mountain area of Tao-Yuan county. We used questionnaire as a tool of exposure measurement. The exfoliated oral buccal cells and blood samples were collected for the assay of micronucleus frequency (MNF) and comet assay. We find that there are higher MNF in smokers, alcohol drinkers, and betel quid users compared with nonusers. However, a significant difference can not be found because of small sample size. The relationship between MNF and three risk factors was strongest in betel quid use, however, for smokers the parameters in comet assay were more sensitive than MNF. There is a tendency of additive effect between cigarette, alcohol and betel quid although without statistical significance. Advanced statistical analysis is suggested to find stronger evidence in the genotoxicity biomarker.
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朝「腎」之旅-鹿角溪水質監測及落葉濾水器和微型人工濕地的製作
濕地是大地之腎,鹿角溪人工濕地的設立,將淨化大漢溪的水質,並提供野生動植\r 物多樣化的棲地。\r 我們探訪鹿角溪人工濕地,聽取監造經理的解說,再沿著鹿角溪河道進行觀察記錄\r 並檢測水質。確認鹿角溪受到汙染後,我們運用人工濕地的淨化原理(初沉池、漫地\r 流區水生植物的淨化、礫間淨化、跌水效應),並結合了落葉(楓香、印度橡膠樹、構\r 樹)及砂石作為濾水器的濾材,製作了一個落葉濾水器。\r 人工濕地淨化水質,需要長時間,落葉濾水器淨化出來的水,靜置在微型人工濕地\r 一段時間後,發現水生植物確實提升了水中的溶氧量。因此,居民若在排放廢水前,\r 若能經過落葉濾水器和微型人工濕地來削減水中汙染物,就可讓河川恢復原有的生命\r 力。
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Technology of web site advancement
Internet by its content represents a fountain of information, while from the point of view of its arrangement it is a huge dump. There are an enormous number of web sites. Multiple web sites are commercially directed, i.e. are aimed at profit earning. As profit depends on the number of visits to web site, no visitors means no profit. So, to obtain more orders, web site producers should first of all ensure good inflow of visitors (web site attendance). Every year this task becomes more and more critical for commercial web site owners (and not only for them), as the number of similar content web sites increases steadily along with competition intensifying correspondingly. The process of establishing conditions to attract more visitors is called web site advancement. The present paper discusses various ways of how to increase the number of web site visitors, it also describes the particular process of "Theater to Children" (www.teatrbaby.ru) web site advancement. Based on the paper outcomes a CD multimedia manual "Technology of web site advancement" has been developed that will help web site producers to achieve good attendance for their network resources. As the purpose of web site advancement is visitor number increase then the main criterion of web site advancement efficiency should be the number of visitors for a certain time period, e.g. for 24 hours, a week or a month. Taking into consideration that about 80% of Internet users retrieve information through search systems, the major growth of visitors will occur owing to the enhancement of web site visibility in search systems.
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