在generalized Petersen graph P(n,5)中的hyper Hamiltonian
Generalized Petersen graph P(n,k),定義為n 為不小於2 的整數以及1≤ k ≤ n−1,有頂點{ u0, u1, . . . , un−1, v0 , v1 , . . . , vn−1 },及路徑{ uiui+1 , uivi , vivi+k:1≤ i ≤ n−1 }。在 [2] 中,我們可以知道P(n,5) 是Hamiltonian 等價於當n≠11。
在這一篇報告中,我們證明當generalized Petersen graph P(n,5) 是hyper Hamiltonian(一種Hamiltonian graph 再去掉任何一點後,仍然是Hamiltonian graph)的充要條件是n 為不等於11 的奇數且n ≥ 7。
The generalized Petersen graph P(n,k), n ≥ 2 and 1≤ k ≤ n−1, has vertex-set { u0, u1, . . . , un−1, v0 , v1 , . . . , vn−1 } and edge-set { uiui+1 , uivi , vivi+k:1≤ i ≤ n−1 with subscripts reduced modulo n}. And we can know that P(n,5) is Hamiltonian if and only if n≠11 from [2].In this paper it is proved that generalized Petersen graph P(n,5) is Hyper Hamiltonian (A Hamiltonian graph can still be a Hamiltonian graph when any one of the nodes fault) if and only if n is odd and n≠11.
環境標籤---地衣與環境污染的探討
隨著工商業發展,環境污染日益嚴重,對多數生長在這塊土地上的人,無疑造成了非常嚴重的影響。但若想要監控目前環境中的空氣品質,則必須具備專業的訓練,及昂貴的實驗設備,對一般民眾而言,根本就做不到。\r 藉由指標植物對所生長環境的高度敏感性,可以發展出一套純天然且免費的環境污染偵測器,不但方便、免攜帶、無須高級儀器協助、更不需要專業的分析技術。為此,我們以對二氧化硫等空氣污染物極為敏感的地衣作為指標植物,對其進行生態與環境污染關係的一系列觀察,並設計相關的實驗,找出環境污染物對地衣的實際影響,使其能夠實際的應用於日常生活,並可加以推廣,讓人人都可以利用地衣來了解自己所處的環境是否遭受污染,為自己家園的環境優劣把關。\r \r 文摘要 :\r With the development of industry and business , environmental pollutions become more and more serious . Undoubtedly , those pollutions have a great effect on us.\r However , by the means of the indicator plant which is highly sensitive to its environment , we can develop a set of natural and free environmental pollution detectors . In this project , we use lichenes,which are very sensitive to air pollution , to do a series of observations and to find out the influence the pollutants have on lichenes . If we can apply this to our regular lives , everyone can use lichenes to see if their environment is polluted or not .
台灣植物染與光敏有機太陽能電池
由於低廉成本、無毒及其他原因,由二氧化鈦、有機染料及電解液所製造的光敏有機太陽能電池(DSC)被預測即將成為一種大規模廣泛流行的太陽能電池。本實驗比較合成染料(像紅汞和疊氮離子)及成本較低且無毒的天然植物染料用於太陽能電池的效能。有些天然植物染料的效能大於合成染料的效能,像是紫色高麗菜、地瓜……等。在研製太陽能電池的過程中, 本研究利用自製的幾丁質燒結出的奈米顆粒成效極佳,不但粒徑大小符合,在燒結的過程中也不需經過物理研磨及介面活性劑的輔助,並且在低溫下即可燒結,並由BET 和SEM 測得幾丁質燒結的TiO2 的孔隙度大於標準燒結的TiO2 的孔隙度,因此本實驗決定利用去乙醯化之幾丁質扮演太陽能電池的二種角色:介面活性劑及保護劑。在本實驗中,部分的電池效能不盡理想,或許是因為所有的太陽電池樣本均使用相同的電解液(I3-)。要找到每種太陽能電池最適合的電解液則需要更多的研究。Because of the desirable features of low cost, non-toxin, and other reasons a dye-sensitized nanostructured solar cell (DSC) composed of nanocrystalline TiO2, organic dyes and electroiytes is expected to be in prevalent use. This study compared the differences in the functioning of different dyes in the solar cells, specifically those between the synthetic dyes, such as Merchrochronate and Polypyridyl complexes of ruthenium (N3-), and dyes made of natural plants which cost less and are not toxic. Some natural dyes, such as purple cabbage, sweet potato, etc, were found to have better efficiency than the synthetic dyes. The study makes use of self-made chitin to sinter nano particles, and the result is excellent. First, the particle radius meets the size requirements. Second, in the process of sintering nano particles, no physical pulverizing or surfactant assistance was needed. Third, the nano particles can be sintered at a low temperature. Fourth, from BET and SEM measurements, the degree of aperture of TiO2 sintered with chitin is superior to that sintered with Triton X-100. For these reasons, the de-acetylated chitin was chosen to serve as surfactant assistance and protector in the solar cells in this study. The study also found that some solar cells were not efficient enough. Maybe it is because all the samples of solar cells in this study were produced with the same electrolyte (I3-). Further study is needed to figure out the most suitable electrolytes for each solar cell.
石油工業廢觸媒於水泥〈砂〉漿中對其流度影響之探討
隨著科技的發達,工業廢棄物應運而生,在地小人稠的台灣,每年就產生約6000 公噸的廢觸媒,為了讓環境免於遭受廢棄物的污染,本實驗著重於廢觸媒的再利用,探討廢觸媒作為混凝土中礦物摻料對水泥(砂)漿流動性的影響。
本實驗所採用的廢觸媒來自石油裂解廠的靜電集塵廢觸媒,主要由SiO2 及Al2O3 所組成且具有部份非結晶相和卜作嵐材料之特性,外觀為乳灰白色粉末、含水量2.8﹪,溶於水中有放熱現象,pH 值為3.85。廢觸媒對水的親和力大,添加至水泥(砂)漿中會使得漿體的流動性減小,因此必須藉由提昇強塑劑劑量才能提高工作度。
在水膠比(W/B)為0.42 時,隨著強塑劑HPC-1000 劑量的增加,水泥漿的流度明顯增加,而且適當量的廢觸媒取代水泥,能維持水泥漿一定的流度。當強塑劑HPC-1000 劑量為3.0﹪、砂/水泥=2.75 時,隨著水灰比(W/C)的增加,水泥漿的流度也明顯增加,而同條件下,不論水膠比(W/B)0.485 或0.55 時,廢觸媒取代水泥之水泥砂漿的流度比飛灰、爐石、高嶺土好,與矽灰相當,其最佳取代水泥量為15﹪。
As technology continues to develop, a considerable amount of industrial wastes have been produced.In Taiwan, over 6,000 tons of spent catalysts were brought out yearly. If such wastes can be reused in some ways, it may be helpful to protect our environment from being polluted. This study was taken to determine the influence of spent catalysts on the flowability of mortar while the catalysts were used as mineral additives for concrete. Since the catalysts could reduce the flowability of cement pastes because of the affinity between the catalysts and water, it was necessary to have superplasticizers added to improve the fluidity of the mortar.
The spent catalysts used in this study were spent electrostatic precipitator cracking catalysts, called Epcat, which were provided by petroleum refining companies. Comprising mainly silicon oxide and aluminum oxide, the off-white catalyst powder present water content of 2.8%, pH value of 3.85 and exothermic reaction with water.
In this study, it was found that while the ratio of water to binder (W/B) was 0.42, the flowability of the cement pastes increased with the increasing addition of superplasticizers. Besides, the flowability of cement pastes kept steady while a proper amount of Epcat was used to replace cement.When the ratio of sand to cement (W/C) was 2.75, with 3.0% superplasticizers HPC-1000 added,the flowability of the mortars markedly increased while the W/C increased, and the replacement with spent catalysts made the mortars show similar flowability as silica fume but better flowability than fly ash, slag and kaolinite, no matter the W/B value of the cement pastes was 0.485 or 0.55. In fact, the best Epcat replacement for cement was 15%.
水滴奇遇記-蓮花效應的真面目
Lotus self-cleaning effect arises because the leaves have the superhydrophobic surfaces. When rain falls onto a lotus leaf, water beads up as a result of surface tension. The water drops promptly roll off the surface, taking every dirt with them. This phenomenon is called the lotus effect. With the aid of a light microscope and an Environmental Scanning Electron Microscope, we observe and describe the morphology of the leaves of Nelumbo nucifera in detail. We successfully observe the real interface between air, water droplets and the papillae of a lotus leaf, and find the evidence of a composite surface that is formed by epicuticular wax crystals and air. These observations improve our understanding of the two-level composite surfaces that are formed by micro-scale papillae, nano-scale epicuticular wax crystals and air. We try the method of using the critical angle of a static drop beginning to roll on inclined surface to evaluate the self-cleaning ability. We then find out that it may be a more precise criterion compared to using the static contact angle for the evaluation of the lotus effect. Literature review shows that the earlier investigation lacks the height(H) and interval(I) of the projections on the lotus leaf surface. A close relationship between the self-cleaning property and the H/I ratio is found. In this study, we present the experimental data of the height and interval of the projections on four different species of plant leaves that all have lotus effect, which may be of great help to technological applications. 蓮花效應是指蓮葉表面具有超疏水性與自我潔淨的能力,當雨水落在葉面,因為表面張力的作用形成水珠,水滴迅速滾離葉面,把灰塵一起帶走。本實驗以光學顯微鏡和環境式掃描式電子顯微鏡觀察蓮葉,詳細描述其表面形態,成功的發現空氣、水滴和蓮葉乳突真實的接觸界面以及表面蠟和空氣構成複合表面的證據。實驗結果可以使乳突、奈米表面臘質和空氣構成的雙層次複合表面更容易被了解。我們嘗試以水滴傾斜滾動臨界角來評估自潔能力強弱,實驗結果比傳統使用靜止接觸角更為準確。表面高度和間距的比值與蓮花效應有很大的關係,查閱文獻顯示蓮葉缺乏這些資料,本研究提出四種有自潔能力的葉子的實驗數據,這些數據應該對科技應用有很大的幫助。
蟹狀星雲的擴張
By comparing eight different epoch images of the crab nebula taken through 1942 to 2004, we have calculated the expansion velocity of 27 optical bubble features and 60 filaments. The mean expansion velocity of bubble features and filaments is 0.173 arcsec/yr and 0.15 arcsec/yr, respectively. We also estimated the maximum radial velocity of the expansion by analyzing the emission spectrum of the nebula. The maximum radial velocity is 1385.5 km/s. Combining these measurements indicates that the crab nebular is approximately 5870 light year away. In addition, if we assume that the nebula has been expanding at a constant rate, our expansion velocity projected backward indicates the mean date of the supernova event as A.D 1124, more than 70 yrs later than the accepted date of 1054. The result confirms the well-known acceleration in the crab's expansion. Although we have analyzed eight images with a 62 yr baseline, the acceleration still can't be derived from this study. 透過量測由1942年到2004年之間八張不同年代的蟹狀星雲中爆炸後殘骸的位置變化,可以計算出蟹狀星雲爆發的擴張速度。本研究選定了27個包狀物和60個纖狀物,計算出的擴張速度分別為0.173 arcsec/yr.和0.150 arcsec/yr。再透過分析蟹狀星雲的光譜所計算出的徑向速度(radial velocity)為1385.5 km/yr,進而推得蟹狀星雲的距離分別為5430光年和6370光年,平均值為5870光年。 另外,如果假設擴張速度是等速運動,那麼把求得的擴張速度倒推出的爆發日期是在西元1124年,這比中國紀錄中超新星爆發的1054年晚了70年。這顯示出蟹狀星雲的確非等速擴張而是有加速度的狀態,才會造成以等速倒推發生日期時,晚了70年。雖然本研究中分析了相差62年之久的八張影像,仍然無法分析出星雲的擴張的加速度情形。
漂浮的油滴--CMC 的測定
Surfactants have a great effect on decreasing the surface tension in aqueous solution and thus they are important components in detergents. The present study aims to explore the cleaning mechanisms of the substances for greasy subjects such as bowls and clothes. The roles of various surfactants that have on the changes in the surface tension of aqueous solution in the presence and absence of additives such as tea and salt have been carefully studied by using a lab-made equipment. We carefully observed the changes in the oil droplets after pushing oil in a syringe to the aqueous\r solution containing surfactants and additives. With decreasing the surface tension of the aqueous solution, the size of the droplet becomes smaller. By using this simple lab-made equipment, we are able to determine the critical micelle concentration (CMC) of sodium dodecyl sulfate (SDS), with a result of 0.0079 M at 20 ℃. The result is in a good agreement with the literature (0.0077M). With decreasing temperature and adding salts such as sodium sulfate, the decreases in the surface tension have been confirmed by our simple experiments. This simple equipment also allows study of the effects of impure additives such as salt, tea, vinegar that have on the changes in the surface tension of aqueous solution containing commercial detergents. We have found that most of the additives have a great effect on reducing the surface tension of the aqueous solution. The present study results suggest that the simple experimental set-up is practical for measuring the CMC of surfactants and for exploring the effects of additives on changes in the cleaning ability of commercial detergents.界面活劑性可有效降低水溶液的表面張力,因此,他們是清潔劑的重要成份。該實驗主\r 要在探討各種物質的清潔機制。利用自製的實驗裝置,針對各種不同的界面活性劑在添加了鹽類或茶水後界面張力的改變量,作詳盡的探討。我們將含有不同濃度界面活性劑以及添加物的水溶液裝入容器中,在推擠針筒使其的油通過針頭並進入該溶液後,我們仔細的觀察紀錄油滴大小的改變。結果顯示界面張力的降低會使得油滴變小。藉這個自製的裝置,在20℃下,本實驗所測得的陰離子型界面活性劑-十二烷基硫酸鈉之臨界微胞濃度0.0079M。結果幾乎與過去的文獻0.0077M 值符合。該實驗同時也證實了降低溫度,添加了鹽類後,可有效的降低界面張力。此外,此實驗裝置也可以用來測量市面上販售的清潔劑在添加了不純的物質後,其界面張力的改變量。我們發現大多數的添加物都能有效降低界面張力。目前的實驗結果顯示,這項實驗裝置在測定臨界微胞上有很高的實用性,同時也可以探討不同的添加物對市面上販售的清潔劑之洗淨力的影響。