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本研究分成二部份。第一部份探討負離子,結果發現不同環境下正、負離子含量有很大差異,且負離子對植物及除煙均有正面效果。第二部份研究電磁波,我們測出了(1)各種電器在不同距離的電磁波強度,進而瞭解其安全範圍。(2)電磁波不利於綠豆生長。(3)手機電磁波實驗測出鋁箔紙、隔熱紙及備長炭布可有效隔絕電磁波50%以上,且隔絕物與電磁波偵測器的距離越大隔絕效果越佳。
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We understood the definition and meaning of spider number by reading〝Wonders of Numbers〞. It interested us so much. So, we took further step to study the situation of extreme value when the gap sometimes lie on the line and sometimes on the circle or even on both. That is to say, we explored the relation between spider number and the gap when the spider number is maximum or minimum. New research for the application of spider number involves several directions. First, we design a new game called〝Stepping Land Mine〞with the rule of spider number. Give you a net with several hidden gaps, trying to find the right positions of gaps. Second is the further result for a different type of net about regular n-polygon. Third is a tactic for a net with destroying of the strategy points. In this situation, the gaps amount on the circle and on the line are fixed. At the same time, consider the situation of circles and lines designing the tactic of placing the gaps to attain the maximum of the destructive effect. 在本文中我們定義一個蜘蛛網上的蜘蛛數,若在蜘蛛網中加入缺口後,會影響蜘蛛數的大小。我們探討蜘蛛網上的缺口,該如何分配才能夠得到蜘蛛數的極值(最大值及最小值)。先觀察一直線和圓上缺口如何放置蜘蛛數有極值,再探討許多條直線及圓上的情況,進而推展至許多同心圓及通過圓心的許多條放射線的缺口,該如何放置,蜘蛛數才會有極值發生。
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基因突變對線蟲(Caenorhabdits elegans)之神經系統退化變異株的搜尋以及對其性??
This research is mainly in observation with Caenorhabditis elegans ’s genetic mutation caused via nervous system abnormal character. In the study, I the sample have been cultivated purified and add some chemical material EMS to speed up C.elegans mutation. Then based on the character to further analysis what causeof gene deal with mutation and observe the effects in heredity. The research has two stages, on the first stage of study the mainly target is to both search and purify the mutation of C.elegans. The second stage is based on the exploration of mutation’s searching andpurifying. Because the certain mutation bodies aren’t easy to find out, the project is still on progress at the beginning of second stage, and we conclude some heredity special cases in preliminary of study. 這個實驗主要是觀察並針對線蟲因為基因的突變所產生的神經系統異常的變異性狀,在實驗中我先將樣品線蟲培養並純化至一定數量,並加入適當藥劑EMS造成其突變,經篩選並分析此性狀,進而找出造成其突變之基因,以及觀察此性狀對遺傳表現所造成的影響。 該計畫分成兩階段,第一階段的實驗重點是在突變株的搜尋以及純化上,第二階段則是在突變基因的探討上,由於特定突變株的搜尋並非容易,所以目前計畫只進展至第二階段的遺傳實驗初期,對於其遺傳特徵與突變形式上已有了初步的分析,但尚未定位出該基因的位置。
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磁浮列車是利用磁力使車體浮起來的一種新穎交通工具,因為並沒有與軌道直接接觸,因此能將只有空氣的阻力減到最小。我們借用磁浮列車的靈感,利用磁?同名極相斥、異名極相吸的原理,製作一列以「磁吸原理」行進的「磁浮」小火車,運用電池為動力,使小火車順利前進。 隨後,基於環保意識,乃將原本以電池為動力的「磁浮列車」改製成以太陽能為動力來源的「太陽能磁浮小火車」。繼而探討不同照度的光線被太陽能板轉換為動能後,對磁浮小火車行進速度之影響,同時完成研究報告。 使用太陽能板,只要在可以接收到陽光的地方就可以產生能量,所以太陽能是解決環境污染及能源短缺的最佳選擇之一。
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隨「吸」所欲—磁性磁磚之改良設計研究
磁磚以鑽孔鎖螺絲釘、貼背膠掛勾或吸附大氣吸盤等方式吊掛物品,其表面會造成傷害或脫落之不便。本研究將不同含量之磁粉與黏土以粉末冶金之方式結合、經高溫燒結與充磁後,成為磁性磁磚,改良以磁鐵鑲埋之製作方法。研究變因包括磁磚原料與磁性原料以分層及混合之舖疊方式、燒結溫度、磁粉層厚度等,研究中發現分層鋪疊之試樣其磁力大於混合後鋪疊之試樣;而燒結溫度較高者,其磁力較高且分層試樣與混合試樣之磁力差距愈小;此外,磁力之大小與磁粉層厚度及燒結溫度成正比;另外,本研究設計一磁性掛鉤配合L字型支撐抵於灰縫後,使磁性磁磚可吸附之掛載重提高近2倍。此磁性磁磚兼具便利性與美觀,提供對於牆面掛放物品之另一種選擇。
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『金來瘋』-金屬廢液利用電解法提高回收效率與節能大小的探討-
本研究在電解槽中額外放入中央碳片進行硫酸銅水溶液電解,發現文獻中沒有探究到的自發性感應電極現象,且可提高金屬的回收量高達對照組的五倍(耗能僅需對照組的14%),其主要發現如下:(1)中央碳片會出現自發性感應電極(偽正極和偽負極);偽正極產生氧氣、偽負極則會析出金屬銅。(2)若改變中央碳片的排列方式,會影響銅金屬總體析出量。以平行排列的析出效果優於垂直排列。(3)試圖建立中央碳片之串聯與並聯的理論類比,可初步成功解釋析出量與效率的差異。(4)若電解槽中央擺置碳片,最高可讓每克銅析出的能量降至原來的14%(同樣耗能下,析出量最高可提高五倍),建議可應用到金屬廢水的回收設計上,達到低耗能高回收的效果。
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Synthesis and Characterization of Niobium Nitride Nanowires
This project aims to explore the potential of inexpensive in-situ deposition of niobium nitride nanowires to improve electrical conductivity. Transition metal nitrides are well known for attributes such as superconductivity, high melting point, simple structure as well as excellent electrical and thermal conductivities. In particular, niobium nitride possesses exceptional hardness and high reflectivity, as well as being a stable field emitter, making it well suited to applications as a cold cathode material. Niobium nitrides are formed by the uptake of nitrogen by niobium. This is achieved by the exothermic formation of an interstitial solid solution of nitrogen atoms in the bcc lattice of the niobium. Existing research has established the possibility of preparing niobium nitride by heating niobium in nitrogen or ammonia over a range of temperatures, by heating niobium pentaoxide and carbon in the presence of nitrogen as well as by chemical vapor deposition of other niobium compounds, nitrogen or hydrogen. For the purpose of this study, a two-step process was used for synthesis. The benefits of a two-step process over direct ammonolysis are apparent, from the greater degree of freedom pertaining to parameter determination. Additionally, characterization of niobium pentaoxide nanowires synthesize under similar conditions is also made possible by terminating the reaction earlier. NbN nanowires were synthesized by annealing niobium pentaoxide nanowires at 850 oC for 2 hours. Subsequent characterization was done using Raman Spectroscopy, X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The presence of NbN nanowires via the conversion of Nb2O5 was ascertained by the absence of sharp peaks at 1000 cm-1 for Raman Spectroscopy and XRD plots. Field emission (FE) properties and electrical properties of NbN nanowires were then measured. NbN nanowires were found to have a high turn-on voltage, stable and relatively good field emission characteristics, demonstrating its potential as a cold cathode material. No current saturation was observed for an applied electric field of 0 to 6.0 V/ μm (5). This suggests a low degree of contact resistance for nanowires produced by this method of annealing, since the passage of electrons is not obstructed. Hence there will only be a small voltage drop between the SiO2 substrate and NbN nanowires. Samples containing NbN nanowires were dislodged by ultrasound to form an aqueous suspension of nanowires. A drop of suspension was dripped onto gold-finger substrates, and current-voltage (I-V) measurements of resultant nanowire bridges were taken. NbN nanowire bridges display Ohmic properties, in comparison with Nb2O5 nanowires that are semiconducting. Nanowire bridges obtained by heat-drying were denser and had better electrical properties than those obtained by evaporation to dryness. NbN nanowire bridges display Ohmic properties, in comparison with Nb2O5 nanowires that are semiconducting. Further work would include varying the cooling processes to observe any changes or deformation. Additionally, niobium nitride nanowires can be hybridized with carbon nanotubes (CNTs). A more in-depth comparison between niobium oxide and niobium nitride nanowires is also proposed, along with exploration of the nitrification of other transition metals.
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長期處理兒茶素對無機砷與氯化鎘之遺傳毒性
重金屬對人體傷害的無遠弗屆-人人皆知,根據流行病學的研究指出,長期處\r 在重金屬含量過高之地區,易造成生理病變。比方說,長期生活在砷含量高的環境\r 中,易導致肝臟、周邊血管及神經系的損害,各種癌症的發生機率也大為提高;長\r 期處在含量過高的鎘環境中,易引起不正常的鈣代謝﹐產生骨質疏鬆症、軟骨症、\r 糖尿、胺基尿酸、尿蛋白、貧血、和肝功能異常的症狀;而目前坊間所看到各類茶\r 品中含有的兒茶素則被發現具有抗氧化、抗突變及清除自由基等功能。故本實驗以\r 人類胃癌細胞(SC-M1)為材料,以微核(micronuclei)偵測技術觀察細胞長期處理兒茶\r 素((-)-epigallocatechin-3-gallate, EGCG)後,對於亞砷酸鈉(sodium arsenite, NaAsO?)\r 及氯化鎘(cadmium chloride, CdCl?)所造成的細胞遺傳毒性有何影響。另一方面則利\r 用SRB 分析法測量細胞存活率,探討長期處理兒茶素後,亞砷酸鈉及氯化鎘對於細\r 胞的毒殺情況是否改變。實驗結果顯示細胞長期處理兒茶素不會造成微核的增加,\r 但是卻會增加細胞的存活率;單獨處理亞砷酸鈉和氯化鎘則都會使細胞中微核明顯\r 的增加,且會降低細胞的存活率;而長期處理兒茶素的細胞對亞砷酸鈉所誘發的微\r 核有抑制作用且會增加細胞對於亞砷酸鈉的耐受度,長期處理兒茶素無法抑制氯化\r 鎘所誘發的微核與細胞毒性。\r \r \r It is well documented that exposure to heavy metals could cause seriously adverse\r effects to humans. Epidemiological evidence has shown that illness is frequently\r observed in residents living long-term in heavy metal contaminated area. For example,\r long-term exposure of arsenic was associated with increased incidences of liver diseases,\r peripheral vascular and neurological diseases, as well as cancers. And long-term exposed\r to cadmium may lead to abnormal metabolism of calcium, osteoporosis, osteomalacia,\r glucouria, aminoaciduria, proteinuria, anemia and abnormal liver function. Recently,\r numerous reports have shown that (-)-epigallocatechin-3-gallate (EGCG), the major\r polyphenol from green tea, have ability to anti-oxidative stress and anti-mutagenesis. In\r this report, we investigated the effects of EGCG long-term exposure in sodium arsenite\r and cadmium chloride induces chromosomal damages and cytotoxicity in a gastric cancer\r cell line, SC-M1. Our present results demonstrated cells long-term exposure to EGCG did\r not induce micronuclei (MN) formation but induce the growth rate. Sodium arsenite or\r cadmium chloride alone significantly induced MN formation and cytotoxicity in cells\r without long-term EGCG exposure. However, long-term treatment of SC-M1 cells with\r EGCG significantly reduced MN formation and protects the cells from cytotoxicity\r induced by arsenite. Long-term exposure of EGCG had no effect on MN induction and\r cell survival in cadmium-treated SC-M1 cells.
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咦!誰把構樹的葉子捲起來了?─螟蛾寶寶捲葉習性的研究
有一天,爸爸帶我們全家去附近的後山爬山,我看到有一樑樹上面的葉子捲了起來,就摘下幾片葉子,攤開其中一片捲葉發現有一隻蟲子,當時心想:「可能是這隻蟲子吐絲把葉子捲起來的。」我開始對這種蟲子感到好奇,於是就找了三個有興趣的同學,一起研究找資料,並請老師來指導我們,希望能多認識牠。
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本研究起於網路教學網站(NLVM的Tessellations),在七個兩兩交集的圈內填入指定的14個數字,使每個圈內的三個數字和均相等,我們稱之為數字邏輯圈。從基本的四~七圈我們一併探究其中奧秘,得知當數組呈現等差數列時,圈數和介在【3n+[(5k-3)/2]xd~3n+[(7k-3)/2]xd】間,且有規律的以公差為間隔出現,且排出的數組及排出的組數前後均具對稱性,更可運用此公式自由設定圈數和,求出可行的數組;或給定內外圈的數組,經雙向脈絡圖輕鬆解題。 以原數組為基模,可經由平移或轉化為正負數、等差數列、小數及分數的過程,形成更多的數組,其組數及對應的位置均相同,可謂變化萬千;再搭配不同的提示位置,將解題的難易度分級,利用各類題本×提示個數×提示位置×提示盤轉動之加乘效果呈現出眾多的題目製成數字邏輯推理盤,以為此研究之具體成果。
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本實驗探討水滴滴落水面反彈的運動情形。我們利用高速攝影機拍攝、觀察水滴滴落水面過程的變化,並改變落下水滴的高度、質量、壓克力水箱的水深,討論不同條件對反彈之分離珠數的影響,以及各分離水珠和落下水滴的能量關係。同時分析水滴撞擊出的凹洞大小,並嘗試以高中課程所學及現有的理論解釋其運動情形。在本實驗中,我們發現:落下水滴位能、水深介於某一範圍時,可出現最多的分離水珠。
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