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反泡泡之形成、存活與破滅的物理特性探討
This research mainly discusses an antibubble the interesting physical phenomenon that isn’t generally noticed .We use digital video cameras to obtain the experimental results, and pick up and analyze them with the computer. The experimental result as follow: (1) The formation of an antibubble mainly relates with the surfactant ingredients.The washing liquid, which has the surfactant characteristics the thinner its concentration; the lower the success rate of the antibubble. (2) The size scope of an antibubble is situated between 0.35 cm to 0.6 cm, and the size of the antibubbles produced by different densities of washing liquids are not obviously different. (3) The interior radius of an antibubble is approximately 3/4 times of the outer radius. (4) The survival time of an antibubble is mostly within 70 seconds, some minority surpasses for 100 seconds. Its average survival time is 40.65 seconds. (5) When the temperature of water the underneath liquid is between 20℃ to 90 ℃, the higher its temperature; the lower the success rate of the antibubble. After the temperature reaches 80 ℃, the success rate of the antibubble turns into 0. Besides, the higher the temperature of water; the shorter survival time of the antibubble. (6) Antibubble die by itself can be induced two kinds of types. One is centralism death, and another one is vibration death. Vibration death is less common and rare. Its dead process lasts longer time than the general antibubble, and also has 2 to 3 times back and forth vibration. 本研究主要要探討「反泡泡」(antibubble)這個一般不被注意到的有趣物理現象。我們用數位攝影機進行實驗結果的取得,並以電腦進行擷取與分析。實驗結果為:一、 反泡泡的生成主要與界面活性劑的性質有關。洗碗精這樣具界面活性劑特性的物質濃度越稀薄,反泡泡的成功越低。二、 反泡泡的大小範圍介於0.35cm 至0.6cm,不同濃度所產生的反泡泡大小並無明顯之差異。三、 反泡泡的內半徑約為外半徑之3/4。四、 反泡泡存活時間大多在70 秒之內,僅有少數超過100 秒,平均存活時間為:40.65 秒。五、 承接液體在20℃至90℃的範圍中,隨著溫度的增加反泡泡生成成功率越下降,在80℃之後,成功率降至0。且溫度增加會使反泡泡存活的平均時間下降。六、 反泡泡自行破滅可以歸納出兩大種類型。其一為:「集中破滅」;另一為「震盪破滅」。「震盪破滅」情形較為特殊少見,其破滅過程較一般反泡泡來得更久,且有2 至3 次的來回震盪。
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界面活性劑因分子一端具極性基(polar group)而有導電性,本研究以市售之界面活性劑(PAOS洗碗精)從事其水溶液導電度探討,實驗顯示,PAOS水溶液之導電度隨溫度升高而增加,90°C之導電度約為常溫之三倍,純水之變化則極微。除溫度外,界面活性劑濃度亦影響導電度,濃度越高導電度越大,定溫(23°C)之導電度隨PAOS含量增加呈直線上升關係,PAOS含量每增2%導電度約增加1000μS,當含10%PAOS之水溶液中期導電度約增為4700μS。乳化效果對導電度亦有明顯之影響。在含PAOS 0.5~3%之水溶液中加入沙拉油,隨沙拉油加入量之增加其導電度均呈現下降現象。例如,在含有PAOS 3%之200克水溶液當中加入10克沙拉油時,其導電度約下降了15%。如果加入更多沙拉油,或者乳化攪拌過後之停滯時間過久,造成乳化平衡破壞,其導電度數據則較不規則。因此,我們可由溶液導電度之量測結果判定乳化效果,並可測定乳化攪拌之最佳條件。實驗除了以導電度探討其乳化效果外,並用顯微鏡同步觀測,以對結果做出更具說服力的解釋。將實驗數據以3D圖(立體圖)呈現以描述系統的連續變化狀態。再利用簡易的曲線回歸、斜率比較等,判定在定溫、一定攪拌條件下,清潔劑的較佳使用濃度。Surfactants have polar end groups at its molecular structure lead it with electrical conductivity in properties. This report discuss conductivity of a market purchasable surfactant named PAOS. Experiment results indicate conductivity of PAOS water solution increases with rising temperature. Triple in conductivity of this solution was found at 90°C than that of at room temperature. While the changes for pure water is very small. Except temperature influence, surfactant concentration also influence its conductivity. Generally, higher concentration gives higher electrical conductivity. At room temperature(23°C) a straight line relationship was observed between the solution concentration and the conductivity. For every increase 2% will led to increasing in conductivity for 1000 μS. When 10% PAOS in water solution is reached 4700 μS in conductivity was observed. Emulsification give obvious inference in conductivity. If cooking oil is added in 0.5~3% PAOS solution, conductivity will decrease with increasing oil added. For instance, when 10 grams of oil was added in 200 grams water solution that contain 3% PAOS, conductivity of this solution decreased for 15%. If more oil is added or setting time is too long after the solution is emulsified that destroy the emulsify balance. The conductivity of the system become irregular. In this way, it is possible to detect effect of emulsify through the measurement in its conductivity. Therefore most favorable condition in emulsification can be determined. In addition to using conductive measurement to determine effect of emulsification, microscopic technique also used trying to find even more convincible explanations. The data of different concentration experimented above can be presented on a 3D chart, we obtain several curves that can be differentially analyzed and estimated for a relatively ideal concentration, which will work more efficiently than others in the condition of the experiment.
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探討如何自製便宜的耐強酸鹼實驗桌面.
This study evaluates the corrosive resistance of strong acid and base for laboratory desks including epoxy resin products, plywood, carbonate products and boards. From results,only the surface of expensive resin products can tolerate the exposure of strong acid and base. The surface of other commercial materials was destroyed with strong acid and base. The performance of laboratory-made desk surface for resistance corrosion of strong acid and base was studied. Coating with Teflon paint on the board could resistant the exposure of strong acid and base, but a drying long time was the major shortage. Some of the chitin added could improve and tolerate the scraping with knife. The results will offer to make a cheaper laboratory desk.
本研究主要是探討不同材質的實驗桌面,如環氧樹脂合成板、三合板、美耐板、一般木板等,其對強酸、鹼的抗腐蝕之極限濃度,進而研發自製經濟實用的耐強酸鹼實驗桌面。由實驗結果顯示,只有較高級昂貴的環氧樹脂合成桌面,才能夠耐高濃度的強酸、強鹼,普通的環氧樹脂桌面、三合板或美耐板其抗強酸、鹼性則不理想。若將一般木板塗以鐵氟龍漆,即可得抗強酸強鹼之桌面材質,但漆不容易乾燥,若添加適量的幾丁質於鐵氟龍漆中,則漆將極容易乾燥,可降低烘烤溫度,使木板不致因高溫烘烤而變形,此所得結果可作為製作價廉的抗強酸強鹼實驗桌面之參考。尤其本實驗所製作之板面以水果刀刮之,板面絲毫未受損,故值得我們廣為運用。
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螯合劑對銅.鉛.鋅離子萃取.分離及測定之微型實驗研究
以微型實驗的方式用螯合劑:dithizone(diphenyl thiocarbazone)在四氯化碳中對金屬離子銅(Ⅱ)、鉛(Ⅱ)、鋅(Ⅱ)進行溶劑萃取與反萃取的平衡所得條件,以及由金屬離子與螯合劑結合時的莫耳數比與分離條件的探討得知,僅僅由控制溶液之pH值便可以使水溶液中的銅、鉛、鋅離子分離。於本研究中所使用之萃取光度分析法,對銅可以測至0-0.1ppm,鉛可以測至0-5.0ppm,鋅可以測至0-0.8ppm;莫耳吸光率分別為:Cu[HDz]2:4.50x104 L/moles‧cm(550nm)。Pb[HDz]2:6.85x104 L/moles‧cm(520nm)。Zn[HDz]2:9.50x104 L/moles‧cm(540nm)。其結果可做為重金屬離子廢水淨化效能之微型檢測指標。
The microscale experiment that the equilibrium of extraction and back extraction of Cu(Ⅱ)、Pb(Ⅱ)、and Zn(Ⅱ) with the extraction of chelate agent- diphenyl thiocarbazone(dithizone) in carbon tetrachloride were investigated. The conditions of extraction and back extraction of pH1/2 and the stability of these chelate compounds have the possibility to separate these Cu(Ⅱ)、Pb(Ⅱ)、and Zn(Ⅱ) mental ions in aqueous solution or in water sample mutually.
The separation and determination of Cu(Ⅱ)、Pb(Ⅱ)、and Zn(Ⅱ) up to 0~1ppm(Cu), 0~5ppm(Pb), 0~0.8ppm(Zn) with dithizone in CCl4 by extraction spectrophotometry has been established.
The molar absorptivity expresssed in Lmol-1cm-1 was found to be 4.50x104(550nm)for Cu[HDz]2, 6.85x104(520nm) for Pb[HDz]2, 9.50x104(540nm) for Zn[HDz]2, respectively.
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耐熱藍綠菌光反應的特殊保護機制─狀態變遷
"隨著全球溫度逐年升高,生物如何在高溫下生存成了一個急需解決的問題,本研究探討耐熱藍綠菌(Thermosynechoccus sp.CL1)與常溫藍綠菌(Synechocystis sp. PCC6803)在不同溫度下光合作用光反應的異同,並了解耐熱藍綠菌光反應耐熱的原因。\r 本研究中發現在高溫下耐熱藍綠菌存在有顯著的狀態變遷(state transition)機制,其藻藍素(phycobilisome)在暗處理的狀況下不會與光系統二結合,而這個機制可以減少光系統二在高溫下高電子傳遞速率對光系統二本身造成的破壞,支持了狀態變遷現象是耐熱藍綠菌在高溫下進行光合作用光反應的一種重要保護機制。"
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在研究水的降溫過程中,經由探討得知散熱速率與溫度有關,而根據理化課本第五章的觀念,熱量的傳遞共分為傳導、對流及輻射三種方式,因此我們根據原理歸納出,散熱速率和溫度的關係式為R(T) = K1T+K2T4-K0(詳見P.11)。接下來,我們從散熱速率對溫度的關係曲線,找出K1、K2及K0,以探討環境條件不同時,熱量傳遞方式所產生的變化。
從實驗結果我們發現,水量越少降溫速率越快,但實際上,水量少傳導和輻射的散熱面積也較小,傳導和輻射散熱的速率隨之降低,因此散熱速率反而較低。此外,我們根據降溫速率、散熱速率和溫度的關係圖及K1、K2 的變化,探討容器厚度、空氣流速、溶液與燒杯外壁顏色不同時,散熱速率的變化,並分析在不同的條件狀態下,熱量傳遞方式的改變。最後,藉由乙醇比熱之測量,進一步驗證所推導的公式。
In the research of cooling down in temperature of water, we realized that the speed of radiation relates to temperature. According to the concept in chapter 5 of Physics, the conveyance of thermal can be divided into three ways which are Conduction, Convection, and Radiation. Therefore, we can conclude the relationship between radiation speed and temperature as R(T) = K1T+K2T4-K0 (see chapter 11). We can find K1, K2 and K0 from the relation curve of radiation speed and temperature to probe into the changes of different thermal conveyances under different environmental condition.
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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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仲夏夜裡的精靈-探討發光胺之化學發光反應與催化劑之作用
過去,螢光的使用只局限於釣魚、登山等無法使用電燈或火把時使用的一種較為安全的冷光。而今,我們使用這種化學發光的機會也越來越多,也再成了更多的汙染,所以我們想藉此去研討有關螢光棒之化學反應與其反應之改良。在這一篇報告當中,我們討論與研究有關Luminol發光之反應與催化劑對其反應之影響;比較在380nm~480nm範圍內不同波長所產生之光度及比較各種不同催化劑在相同波長的發光度隨反應時間的變化。我們發現在此反應之中,以k3Fe(CN)6可以產生出最大的亮度,且由實驗的結果得知Luminol的發光無法維持兩分鐘,發光時間較為短暫。映之催化效果是同時被金屬離子和根離子影響。具有明顯催化效果(最大光度超過2.5)的鹽類濃度以稀薄為佳,約10-3M。在此反應中以k3Fe(CN)6為其催化劑,可以產生一種穩定且明亮的發光,是一種較佳的催化劑在此化學發光反應之中。In the past, fluorescence was limited in being used in fishing or hiking, in which light or a torch was not available. Fluorescence is much safer because of its feature of luminescence. Today, the opportunities we use this fluorescence become more and more. The more people will use fluorescence. The more environment pollution will be caused, that is the reason we would like to study the chemical reaction of fluorescence and its solution to reduce pollution. In this paper, chemical reactions between the Luminol and different catalysis agents are studied, the comparisons between the reaction condition of the catalysis agents and the Luminol, to measure the light intensity variation in 350-500nm light wavelength range. And to measure the light intensity variation following the time of the chemical reactions between the Luminol and different catalysis. We found out that the chemical reactions between the Luminol and k3Fe(CN)6 being the catalysis agents can produce the maximum light strength. But the time of the chemical reactions is much shorter, it only can keep this chemical reactions operating in two minutes. The chemical reaction’s catalysis agent is affected by metallic ion and SO4(2-) , NO3(1-),Cl(1-), when the catalysis agent’s concentration is sparely, this luminous reaction is more obvious( the maximum light strength is over 2.5) .It can produce a fluorescence which is steady and luminous, and it is better to become the catalysis agent material of the fluorescent chemical reactions.
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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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植物依靠向光性爭取最多的光線,以進行光合作用,製造食物供給所有生物。雖然在十九世紀時植物的向光性就已經被發現,並且參與植物向光性的主要荷爾蒙為植物生長素也已經熟知,但是主要是植物的哪一個組織接受光訊息以誘導向光性,以及細胞內的哪些分子參與訊息傳遞,則都不清楚。因此這個研究,以可以發射特殊波長的發光二極體為光源照射綠豆小苗以研究向光性,結果顯示藍光和綠光而不是紅和黃光可以誘導向光性。就向光性訊息傳導的組織層面的研究而言,將豆苗的葉、葉柄、生長點、子葉分別除去後,再側面照光,發現向光性要產生必須要有生長點或葉柄,並且發現莖可以誘導向光性,而葉子不能誘導向光性,因此莖是主要接受光訊息以誘導向光性的組織。就向光性訊息傳導的分子層面的研究而言,植物以鈣離子的螯合劑和鈣離子通道阻斷劑處理後發現,細胞質內鈣離子濃度的增加是藍光和綠光誘導的向光性所需要的過程,有趣的是藍光誘導向光性的訊息傳導過程中,除了經由細胞內的鈣離子濃度的增加外,還有其它鈣離子不參與的訊息傳導途徑。此外,以蛋白質磷酸?抑制劑和蛋白質去磷酸?抑制劑處理植物後發現,藍光和綠光所誘導的向光性訊息傳導,都包含蛋白質去磷酸?第1 和2a 型在細胞內的作用。因此植物的向光性需要有生長素才會表現,生長素由生長點製造後由生長點和葉柄儲存,在光刺激之下會誘導莖產生傳遞訊息,此訊息會傳遞到含有生長素的生長點和葉柄,使得生長素流向照光組織細胞,並且使得細胞內鈣離子濃度增加,活化蛋白質去磷酸?第1 和2a 型,進而造成植物的向光性。Phototropism allows plants to receive the most amount of light to perform photosynthesis, which produces food and energy for all organisms. The phenomenon of phototropism has been known since the 19th century, and auxin has been identified to be the main hormone involving in phototropism. However, the major plant tissue responsible for receiving light signal is not fully understood, and the signal transduction pathway within cells after light activation is not clear. Therefore, the phototropism of mungbean seedlings is examined by Light Emitting Diodes (LED) which produce the specific wavelength of light in this study. Results point out that blue and green lights rather than red and yellow lights induce phototropism of moonbeam. The phototropism of mungbean seedlings is further studied by plants whose leaves, petioles, apical meristem, or cotyledons were removed, showing that the presence of either apical meristem or petioles is needed for inducing phototropism. Also, stem ,not leaves, is the major tissue that receives light activation, and induces phototropism. The signal transduction of phototropism was further analyzed in the presence of calcium ion chelator and channel blockers. The signal transduction of phototropism induced by blue or green light contains the increasing concentration of calcium ion within cytosol. Interestingly, there is a calcium-independent tansduction pathway for blue light only to induce phototropism. Additionally, staurosporine (STA), a protein kinase inhibitor and okadaic acid (OKA), a protein phosphatase inhibitor, were used to study the signal transduction pathway of phototropism, and results indicated that protein phosphatase 1 and 2a is needed for both blue and green lights to induce phototropism. Conclusively, the phototropism is triggered by the reception of light by stem, and the light signal is transferred to apical meristem and petioles that reserve auxin produced from apical meristem. Auxin is then transferred to the cells that is illuminated, increases the concentration of calcium ion and activates protein phosphatase 1 and 2a in cells, and finally phototropism occurs.
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畢氏定理(a²+b²=c²)歷經25世紀,發現了數百種的幾何論證法;而畢氏定理演繹出的正三角形 ( (/4) a²+(/4) b²=(/4) c² )幾何分割研究,卻一直沒有人研究。因此,承襲著之前處理幾何問題的經驗,決定挑戰畢氏定理演譯的正三角形分割研究。本文研究兩正三角形,經切割後拼成另一大正三角形;期間以GSP及AutoCAD繪製分析幾何圖形,並建立了4種分割模式,得到了3段式「最佳分割模式」及準「通用分割模式」,提供這方面問題一個可應用於所有條件之完善解決方案。本研究成果豐碩,補足了相關領域的空檔,且可製成益智又富挑戰性之拼圖系列,不管用做教具或遊戲,對建立意至己和相關資料有莫大貢獻!
Twenty five centuries after its discovery, hundreds of proofs have been given for the Pythagorean Theorem (a²+b²=c²). But, research about regular triangle dissection extending from Pythagorean Theorem has always been lacking. So, based on previous experience with geometric dissection problems, I have decided to do a research on regular triangle dissection extending from Pythagorean theorem. This research dissects two regular triangles and assembles them into a large regular triangle. Using GSP and AutoCAD to draw and analyze geometric shapes, four dissection models and nine dissection methods are constructed. The extreme values under all conditions are also discussed, as are the best and generic dissection models. There is a Three-section type “best dissection model” and a semi “generic dissection model.” offering a perfect solution to this kind of problem that can be used under all conditions. This study yields numerous results as well as filling in blanks in similar fields. It can also be made into challenging jigsaw puzzles for educational or entertainment purposes.
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Thelytokous Parthenogenesis by egg-laying workers in the Black Ant, Ochetellus glaber. (Hymenoptera: Formicidae)
孤雌產雌(Thelytokous Parthenogenesis) 是一種雌性個體未經過交配,自行產出擁有雙套染色體之雌性子代的生殖行為。目前在其他已發表的文獻中,僅有四種亞科的十一種螞蟻採取此種生殖方式,並依照其形式的不同,區分成三種孤雌產雌的類型。本研究主要針對光滑管琉璃蟻工蟻的孤雌產雌行為進行探討,證實未與雄蟻交配過的工蟻,能自行產下具有雙倍體的後代。統計結果指出,超過87%的大型聚落是由產卵工蟻領導,形成缺后聚落,而每一個蟻巢至少會有80%以上的工蟻轉變為產卵工蟻。\r 研究中也發現,產卵工蟻的產卵速率明顯高於蟻后、其子代發育週期亦較蟻后短,顯示出光滑管琉璃蟻缺后聚落以孤雌產雌擴張的優勢。大多數的產卵工蟻在外型上較一般工蟻長,我們能夠在其腹間膜膨大時觀察腹部內加以區分二者。當蟻巢位處於休眠狀態產卵工蟻的表面碳氫化合物與內部腺體的組成成分與一般工蟻有別,而解剖後可在其微卵管中發現卵。此外,兩者在分工上,產卵工蟻除了確保聚落的繁衍,還需照顧其手足;一般工蟻則負責巢外的覓食與警戒等工作。\r 本研究首次記錄了琉璃蟻亞科行孤雌產雌的行為,而這種對於孤雌產雌與有性生殖並行之蟻種的探討,也?孤雌產雌創立了一個新的研究方向。
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