長方體內最少完全城堡數
我們試著尋找所需最小的城堡個數以看守整個a × b × c (a,b,c ? N) 的長方體。所謂城堡是一種棋子,當放置城堡的位置是(x, y, z) ,則(x, y,t)、(x,t, z)、(t, y, z) (t 是任何不超出邊界的正整數)是這個城堡可以看守的格子。我們用這些城堡來完全看守長方體,試著找出其最小值。在2005 年我們猜測了a = b = c 、a = b c 、a > b > c 的上界,而在2006 年時完成了a = b = c 、a = b c 的大部分情況的證明,少數不能解決的部份也提供了不錯的上界。目前我們在a = b = c 、a = b c 的情況幾乎完全解決,目前正在向a > b > c 的部份發展。A generalized searching method of finding the minimum number of castle which can oversee all over the rectangular box, defined as a × b× c (a,b,c ? N) , is presented. The castle here is defined as one kind of chess. The castle positioned as (x, y, z) can direct the lattice points of (x, y,t) 、(x,t, z) 、(t, y, z) (t is the positive integer and smaller than the box size). These castles we use here is to oversee the rectangular box and to help us to find the minimum number. In 2005, we got the upper bound of overseeing the rectangular box in the conditions of a = b = c、a = b c、a > b > c , while in 2006 we complete the proofs of the minimum number of castles based on the conditions of a = b = c 、a = b c . The further work we want to attain is to complete the case of a > b > c.
芯電感應
Based on Ampere,s Law, the magnetic field intensity of the solenoids is B=μ0μr?n?I, where μ0 is the magnetic permeability of free space, μr is the relative magnetic permeability, n is the number of coils per unit length and I is the solenoidal current. The end magnetic field of the solenoid must multiply by one half. According to the above result, it can be greatly strengthened by the addition of a ferromagnetic core. First, we observe three different inserted materials of coils (wood, iron and magnetite), whose magnetic induction in different solenoidial current. By experiment, when the iron and magnetite materials were inserted into the coil, it would produce larger magnetic induction. The calculated relative magnetic permeabilities of wood, iron and magnetite materials are 0.57, 18.37 and 18.32, which are close to the reported paper (1). When the driving field is removed, the fraction of the saturation magnetization of the magnetite is retained, which is called hysteresis and is related to the existence of magnetic domains in the material. In the second part, we change the frequency of circuit switch, which induced different current. Compared with the result of the first part, it would fit the result, which is the induced magnetic field is proportion to the solenoidal current. 根據安培定律,螺線管的磁場為B=μ0μr?n?I。其中μ0為真空中的導磁率,μr為相對的導磁率,n為單位長度的線圈匝數,I則為通入螺旋管的電流。至於螺旋管的端點磁場須再乘上1/2。所以根據上述的結果,當螺旋管插入鐵磁性物質,會增強螺旋管的磁場。首先,觀察三種不同的芯物質;非鐵磁性材料,軟磁材料,硬磁材料(木棒,低碳鋼棒,磁鐵棒)在不同的外加磁場下的感應磁場,得到芯物質的磁化曲線,而計算出來的相對導磁率分別為0.57, 18.37 和18.32與參考文獻(1)接近。而當外加磁場移走時,硬磁性物質的磁性仍然存在,稱為殘磁現象。在第二部分,我們改變線路開關的頻率。發現不同的開關頻率,會得到不同的螺旋管電流,而造成不同的感應磁場。再度驗證了感應磁場大小是正比於螺旋管電流的大小。
以廢找廢~讓重金屬離子無所遁形~
在相對較高氧化電位下的前處理,這樣的活化步驟已被普遍接受。藉由這樣的活化步驟,廢煤渣(傳統鋼鐵業)轉變成能夠有效偵測微量鉛金屬離子的催化劑。微量鉛金屬離子的偵測是藉由方波剝除伏安法進行。在最佳化參數下,偵測鉛金屬離子的靈敏度為11.482μA/ppm(斜率??),線性範圍為0.1-2ppm。最後,照光設備之應用亦可用來提升偵測鉛金屬離子時之靈敏度。最終實際應用則取天然的水進行實驗之驗證。The preactivation process (i.e., preanodization) at very positive potentials has been accepted as the prime activating procedure. By using the preactivation process, waste cinder (from steel industry) were converted into an efficient catalyst in the determination of Pb2+ in cinder-modified carbon paste electrodes. The possibility of determining Pb2+ at trace levels was examined by square-wave anodic stripping voltammetry. Under the optimized analytical conditions, the sensitivity, linearity, and detection limit are 11.482 μA/ppm, and0.1-2 ppm (r = 0.974). Finally, the lighting was also used to raise the sensitivity of the determining Pb2+. The practical applications were demonstrated to measure trace Pb2+ in natural waters.
利用奈米級的二氧化鈦〈TiO?〉在紫外光降解幾丁聚醣的研究
本實驗中利用二氧化鈦能在常溫下經紫外線催化,分解空氣中的水分子,產生自由基的特性,攻擊幾丁聚醣中碳與氧鍵結的部分,使chitin 的分子量成功的從近50000 降解至3000以下;並可利用照射時間的不同,降解出分子量不同的chitin。此法不但大大排除利用化學法降解時廢液處理上的問題,而且還能利用照紫外光時間長短的不同來控制分子量的大小;又奈米級二氧化鈦(TiO?)在紫外光在短短四個小時之內就有很好的降解效果,除了節省了反應所需的時間外,降解前後幾丁聚醣的濃度也很高,因此所需的成本也遠低於當今利用酵素降解的方法。In the experiment, we used the properties of TiO? that can be catalyzed by UV rays and breaking the molecules of H?O and produce free radicals, which free radicals can attack the chemical bond between carbon and oxygen in chitin, successfully degrading chitin's molecular weight from 50000 to 3000.We also use different shining times to degrade chitosan into different molecular weight. In this way, we not only readily solve the problem of treating waste liquids produced by chemical degradation, but also control the molecular weight by different UV ray shining time. For another thing, TiO? in the nanometer level has excellent effect on degradation within 4 hours under UV ray shining. It not only cut back the reaction time but also produced high concentration of the chitin after degradation. As a result, the cost is much lower than that of using enzyme to degrade chitin.
一個也沒漏掉,一個正有理數的排序的研究
本文中我們探討一個有趣的數列。這個數列有一個非常特殊的性質:將數列相鄰兩項的前項當分子,後項當分母,所產生的分數數列,恰好會出現所有的正有理數。 這個特殊的性質表示,可以將正有理數按照這個方式作排序,這個排序將完全不同於常見的正有理數排序的方法。
(1). 在正有理數的排序的結構中,我們做出許多有關於此數列的定理。
(2). 用數學歸納法證明此分數數列涵蓋所有正有理數,且每一正有理數只出現過一次。
(3). 將數列分割後,利用試算表製成數列規則表,並整理出快速的方法將數列表達出來。
(4). 將an 數列排成“樹"的模式,可更快速的把正有理數寫下來。
(5). 最後,設計出搜尋正有理數的演算法,解決在分數數列中第n個正有理數會是多少;以及正有理數會出現在數列中第幾項的問題。
Let’s discuss an interesting sequence. There is a very special quality in it. In this sequence, choose two numbers, which are close to each other, and suppose the first number as “member” while the second one as “denominator.” Then we can get a fraction sequence that includes all of the positive rational numbers! According to this special quality, we can arrange positive rational numbers by the following method. Then we can get a brand-new way of the arrangements.
(1). We can find many theorems about this sequence according to this special arrangement of the positive rational numbers.
(2). We can prove the rule that this fraction sequence includes all of the positive rational numbers by mathematical induction. Furthermore, every positive rational number appears only once.
(3). After dividing this sequence into several parts, we can get a sequence rule list by using trial balance and find a faster method to express the sequence.
(4). Arrange the an sequence by the tree model. By this way, we can get all of the positive rational numbers much faster.
(5). Finally, we can develop the operation method to solve the questions that what position would one positive rational number be in the sequence and what is the first, second, third or nth positive rational number of the sequence.
讓瓶塞隨心所欲
這是一種可在膨脹狀態及未膨脹狀態間轉換的膨脹收縮瓶塞。本設計之瓶塞包含一彈性橡膠之塞座及一剛性塑膠之旋轉控座。該瓶塞在未膨脹狀態,可將瓶塞置於平口內將瓶塞順時針方向旋轉90度使瓶塞由未膨脹狀態轉換至膨脹狀態將瓶子密封;欲開瓶時將瓶塞逆時針方向旋轉約90度使瓶塞由膨脹狀態轉換至未膨脹狀態,可輕易將瓶塞從瓶子內拉出。根據顧客之需求設計瓶塞並選定適當之塑膠材料以製作旋轉控座及適當之衛生橡膠以製作塞座,依廠商提供塑膠及衛生橡膠之特性資料做有限元素分析預測橡膠元件受撐大之變形量,進行加工與製造印證分析之結果,與預期目標有相當的差異,故製作簡易之試件進行探求塞座內縮量與瓶塞膨脹量之關係, 探求瓶塞膨脹量與瓶子所能承受的壓力之關係,進而逆向設計瓶塞之塞座內縮量。 This is a kind of bottle plug that can change at the situation of swell or unswell.The design of this bottle plug includes a rubber plug and a rigid plastic controller that can revolve around. We can put the bottle plug at the top of the bottle and rotate it 90° c.w., the bottle pug will be at the situation of swell and then seal up the bottle. If we want to open the bottle, we just rotate 90° c.c.w., and the bottle plug will be at the situation of unswell and then we can pull the bottle plug out easily. I design this bottle plug according to the need of the customers; choose the certain plastic material to make the rigid plastic controller, and the properly rubber to make the plug; analyze and predict the amount of deformation by Finite Element Method in accordance with the characteristics of rubber and plastic supplied by the factories. However, the result and the expected result are quite different. In order to solve the problem, I make an easy sample to search for the relationship between the contraction of the rubber plug and the swells of the plastic controller and also the relationship between the swells of the plastic controller and the pressure that the bottle can endures. Then I design the contraction of the rubber plug on the base of the result of the experiment I made above.