全國中小學科展

2007年

澱粉?抑制劑之研究

植物合成澱粉?抑制劑可以對抗動物的取食,國外實驗證明數種澱粉?抑制劑對害蟲防 治具有顯著效果,其中以腰豆(Phaseolus vulgaris)研究最多。我們利用5% T.C.A.進行粗萃,從台灣常見豆類中篩選出四季豆(與腰豆同種不同品系)與菜豆,對麗蠅的澱粉?具有明顯的抑制效果,對豬胰臟與黃豆澱粉?的抑制效果則小或無,此種抑制特異性深具害蟲防治的潛力。經由溫度與pH 的試驗發現粗萃中的澱粉?抑制劑成分應為蛋白質。我們以四季豆作為繼續研究的對象,將粗萃進一步純化,經由陰離子交換與膠體過濾層析,分離出單一蛋白質,經蛋 白質定序比對確認其可能為國外發表的腰豆澱粉?抑制劑—αAI-1。經由測試發現此抑制劑在 85℃時仍能抑制果蠅澱粉?,為一相當穩定的蛋白質;且抑制劑的作用受pH 值影響很大,在偏酸性環境下的效果最好,與昆蟲分泌澱粉?的部位亦為酸性環境有相當密切的關聯;且其 抑制作用具特異性,可明顯抑制果蠅、入侵紅火蟻、白蟻、蟑螂及麵包蟲等昆蟲的澱粉?活性,對人類唾液、豬胰臟、四季豆本身及黃豆澱粉?的抑制效果很小或無,值得繼續深入研究。 Plant amylase inhibitors can fight against predation from plant-eating animals. It has been reported that several amylase inhibitors have an obvious effect on pest control; among them that from Phaseolus vulgaris got the most surveyed. 5% T.C.A was employed to make crude extracts. We have screened the amylase inhibitor activities from crude extract among beans common in Taiwan. The inhibitors from both string beans (the different strain of Phaseolus vulgaris) and cowpea notably inhibited the amylases in Chrysomia megacephala, but little or no inhibition in porcine pancreas and soy bean. This specific inhibition behavior suggested strong potential in pest control. Its activity can be affected by temperature and pH suggested that amylase inhibitors in crude extracts should be proteins. String beans were chosen to be further purified from the crude extracts. A single protein was isolated after ion exchange and gel filtration chromatography. Through protein sequencing, the partial amino acid sequences were highly homologous to that ofαAI-1 from Phaseolus vulgaris, indicating it might beαAI-1. The purified protein still can inhibit the amylase from Drosophila melanogaster at 85℃, suggesting it is thermal-stable. Its activity was affected by pH and reached the peak in weak acidic environment, which might be related to the fact that amylases are secreted in acidic environment of insect’s midgut. It obviously inhibited the amylases from D. melanogaster,Solenopsis invicta, Odontotermes formosanus, Periplaneta Americana Linnaeus, and Alphitobius sp., while not to human saliva, porcine pancreas, soy bean and string beans itself. The unique pattern of inhibition activities of the purified amylase inhibitor was worthy of further anlysis.

磁場中的離子轉速-探討離子遷移速度變因

帶電的離子受到垂直的磁場與電場作用,會因為受到洛倫茲力而產生有趣的轉動現象。我們利用上述原理設計簡易的裝置設備,探討電解質溶液不同濃度、不同離子電荷數,受到不同離子間靜電力,產生不同的離子移動速度。經由所測量的時間與圓周運動的距離,可計算電解質的絕對遷移速度。由實驗結果推論在固定電場下,當電解質濃度降低,正、負離子間的相互作用力降低,離子遷移速度(migration velocity)加快,莫耳電導率 Λ(mole conductance)也隨之增加。同濃度時,電解質2-1 價型硝酸銅與2-2 型硫酸銅離子強度(ionic strength)不同,2-2型硫酸銅離子強度較大,遷移速度較小,莫耳電導率Λ 也較小。Because of the effect of Lorentz force, charged ion will have interesting rotation under the vertical magnetic and electric field. We use the above principle to design a simple instrument or tool, in order to evaluate and study the formation of different ionic mirgration velocities. The velocity of the charged ion in the instrument is affected by differences in the electrolyte, the charge differences of the ion tested and the differences in electrostatic forces between ions. From the experiment we can deduct that at a fixed constant electric field, when the concentration of the electrolyte is reduced, the interaction of forces between positive and negative ions will be reduced. When the migration velocity of ions increase, the mole conductivity Λ (mole conductance ) will also increase. At the same concentration, the ionic strength between copper nitrate ( 2-1valency type ) and copper sulfate ( 2-2 valency type ) are not identical. Copper sulfate, a 2-2 valency type has higher ionic strength, the velocity is slower and the mole conductivity Λ is also smaller.

Development of an Inexpensive Raman System and a Littrow Spectrograph

「風笛」是台灣原住民鄒族的信號用具及祈雨法器,由一條繩子綁一支竹片構成。轉動風笛時,竹片會繞繩子自轉並拍打空氣而發出聲音,並有上下飛舞的現象。 \r 風笛產生聲音的原因,為竹片拍打空氣而造成的渦流共振現象;又由於繩子扭力大小及方向改變,使風笛的音調忽高忽低、響度忽大忽小、且竹片會在兩個平面上公轉,而有週期性變化。 \r 施力使風笛公轉轉速加快時,竹片自轉速率也變快,使其音調愈高、響度愈大;而繩愈短、愈粗時,竹片的公轉週期將愈短。

溫差電池的熱力學研究與應用

溫差電池中若僅進行的反應,則其電池電壓與溫差成正比,且純粹是利用化學反應將熱能轉換成電能,我們稱之為「典型溫差電池」,由熱力學公式可推導出典型溫差電池的電動勢(ΔS = S(s)—S(aq),S為絕對熵, n為得失電子數,1F = 96487 C ),且得到下列三項推論來說明溫差電池的特殊現象。 (1) 同一溫差電池,其電動勢與溫差成正比 (ε∝ ΔT)。(2) 不同的溫差電池,當溫差一定時,電壓ε 與ΔS 成正比,與得失電子數n 成反比。典型溫差電池中,電解液濃度越小,金屬離子濃度也愈小,會使得ΔS = (S(s)—S(aq))的絕對值變大,因此溫差電池的電壓也就愈大。(3) ΔS 值的正負決定電壓ε 的正負。Cu(NO3)2 及ZnSO4 溫差電池的ΔS 為正值,所以高溫杯為正極;AgNO3 溫差電池的ΔS 為負值,所以高溫杯為負極。因水溶液中陰、陽離子不能單獨存在,所以單一離子水溶液的絕對熵無法求得,但科學家把氫離子水溶液的標準絕對熵定為零,藉以求出其它離子的絕對熵,然而我們測得在一定溫差時典型溫差電池的電動勢ε,再查得金屬的標準絕對熵 S(s),代入S(aq) = S(s) — nFε/ΔT,便可得到離子水溶液的絕對熵。Cu(NO3)2 溫差電池的電解液中若含有1M 或0.5M 的KNO3,電池電壓仍然與溫差成正比, 但卻可獲得較大的電流,我們稱此類溫差電池為「改良型溫差電池」。我們利用改良型溫差電池的原理,自製環保、節約能源、可重複使用的實用溫差電池,以PVC 水管當容器,上、下兩端開口用銅片封住當電極,管內裝海棉及0.125M Cu(NO3)與 1M KNO3 溶液,熱源加熱上層銅片形成溫差,當溫差維持在70℃,電壓約為70 mV,若串聯30 個實用溫差電池,電壓可達2 V 以上,就可以對鉛蓄電池充電。實用溫差電池的熱源可由回收冷氣機、工廠的廢熱,或直接利用太陽能來當熱源。 If the temperature difference cell only goes through the following reaction Then the potential created by the cell is proportional to the temperature difference, and such a reaction purely changes the thermal energy into electrical energy through chemical reaction, which we often name it “typical temperature difference cells”. We can come to the following formula for the typical temperature difference cells through a series of thermodynamic formula: ε= ΔT . ΔS/ nF (ΔS = S(s)—S(aq), where S is the standard 3 entropy, and n is the number of electrons gained or lost, and 1F = 96487 C). We also provide the following three inferences to demonstrate the special phenomenon for the temperature difference cells: 1. Within the same temperature cell, the electromotive force (EMF) is proportional to the temperature difference. 2. When the temperature difference keeps constant, the electromotive force is proportional to the ΔS in different temperature cells, and is inversely proportional to the number of electrons gained or lost. Within the typical temperature difference cells, when the concentration of the electrolyte becomes more diluted, the concentration of the metal ions also proportionally become lower, which will make the absolute value of the following equation bigger, as a result, will make the electric potential of the temperature difference cells bigger: ΔS = (S(s)—S(aq)) 3. The value of ΔS decides the value of the electromotive force. The ΔS of the following temperature difference cells is positive value: Cu(NO3)2 and ZnSO4 . As a result, within the copper and zinc temperature difference cells, the higher temperature glass is the anode. On the other hand, the ΔS of the AgNO3 temperature difference cell is negative, which means that within the silver temperature difference cell, the higher temperature glass is the cathode. Meanwhile, because the cations and anions can not exist alone, therefore, it is not possible to find the standard entropy of the single ion solution. However, scientists define the standard entropy of the solution containing hydrogen ion to be zero, as a result, we only have to determine the electromotive force for a typical temperature difference cell, while keeping the temperature difference constant, followed by finding the standard entropy for the said metal S(s). Inserting it into the following equation to find the standard entropy for the ion solution. S(aq) = S(s) — nFε/ΔT If the electrolytes for the Cu(NO3)2 temperature difference cell contains 1M or 0.5M KNO3 , the electromotive force is still proportional to the temperature difference, and we can obtain bigger electric current. We call this kind of temperature difference cells “improved version of the typical temperature difference cells”. We try to make more environmental, energy saving, and recyclable temperature difference cell by applying the theory of the improved version of the typical temperature difference cells. We use PVC water pipe as the containers, both edges of the pipe sealed with copper metals, also work as the electrodes. Within the pipe filled with sponge and 0.125M Cu(NO3) and 1M KNO3 solution. The heat source keeps heating the upper copper metal to keep constant temperature difference. When the temperature difference is kept around 70℃, the electric potential is 70 mV. If we can connect 30 practical temperature difference cells in a series, the electric potential will reach 2V, which can then charge the lead rechargeable battery. The heat sources of the practical temperature difference cells can be supplied by the recycled air conditioners, heat waste from a factory, or directly comes from the solar power.

約瑟夫問題

最後留下數字會是多少?該問題在台灣的全國中小學科學展覽出現多次。而資訊界演算法大師Donlad E. Knuth 在其著作The Art of Programing,CONCRETE MATHEMATICS (具體數學),針對該數列作詳細的說明;但是,不論是歷屆全國中小學科學展覽或是大師著作,對於該問題,都只是談及殺1 留β或是殺α留1。本研究利用獨創α分類、n 及k 分類、d 函數、b 函數及循環、n 及y 分類、碎形數列和演變關係,將約瑟夫問題探討範圍提升至殺α(個數)留β(個數),直到剩下最後1 個數時就不能再殺了,遊戲終止,倒數第k 個留下的自然數是多少?同時,本研究在殺α(個數)留β(個數)下,指定自然數y 為酋長,酋長不能被殺,殺到酋長時遊戲停止,求剩下的自然數有幾個?會發生什麼情形?The Josephus problem refers to what will be remaining when arranging n natural numbers in a circle and starting killing one and leaving the next one alive. The problem has been on display for many times in Taiwan National Primary and High School Science Exhibitions (as shown in Table 1). And, the information algorithm master, Donald E. Knuth has elaborated on the array in his works The Art of Programming, CONCRETE MATHEMATICS. However, both the past science exhibitions and the master’s works are limited to discussions on cases of killing 1 leaving β or killing α and leaving 1. This research employs uniquely created α classification, n and k classifications, d function, b function and loop theory to extend the Josephus problem scope to killing α leaving β to find out what the remaining natural number is by No. k counted recursively. Meanwhile, this research designates natural number y as the chieftain, which can never be killed. The game is over when the chieftain is to be killed. The problem is to work out how many natural numbers are remaining. And what happened?

小小細菌立大功-油類生物復育模式的探討

20 世紀初,石油的量產造就了人類文明前所未有的繁榮,然而由於運送、廢棄處理等因素,使得油類污染成為環境保護的重大議題。本實驗中,我們的研究主題為在受油污染的土壤中純化並鑑定出可分解油類之土壤菌和綠膿桿菌對可分解油類之土壤菌與這群土壤菌彼此之間的交互關係,藉此了解它們間的互動對環境生物復育的影響。我們由受油類污染的行道樹土壤中分離了約12 種的土壤菌,其中我們得到3 種對油類分解效果效果極佳的非綠膿桿菌(暫時命名為P7A、P7C、P7D)。經過菌種鑑定發現P7A、P7C、P7D 均為格蘭氏陽性菌。為了解這群可分解油類之土壤菌間的互動關係,我們針對分解效果最佳的P7A、P7C、P7D 作為研究對象,將菌落接種至含有鹽類與機油的液體培養基中震盪培養,並每隔一定時間測量其O.D 值。結果發現P7A、P7C、P7D 間的互動會導致其在以機油為單一碳源的培養液中之生長速度的改變,因此在行環境生物復育時須注意土壤菌間交互關係對其分解污染物速率的影響。此外我們由受油類污染的行道樹土壤中亦分離出了一些綠膿桿菌,因文獻指出,綠膿桿菌所分泌的綠膿素降低受油污染土壤中土壤微生物相的多樣性;因此,我們將由行道樹土壤中純化出的綠膿桿菌T3 與可分解油類P7A、P7C、P7D 進行交互作用觀察,發現T3 會侵占P7A、P7C、P7D 的既有菌落區,而平板培養基亦可清楚看出和T3 交接的P7A、P7C、P7D 菌落區寬度有明顯降低,因此我們認為T3 可抑制或殺死P7A、P7C、P7D,可得知綠膿桿菌會對可分解油類之土壤菌產生抑制或競爭關係。In early 20th century, the exploitation of petroleum transformed human civilization into a tremendously prosper stage. Because of the transportation and disposition of petroleum, the oil pollution has become a important issue in environmental protection. Besides, Chloropseudomonas spp. which can survive in many different environments and decompose lots of organic compounds. In this study, we want to find the bacteria which can utilize oil from machine oil-contaminated soil, investigating the interaction relations between Chloropseudomonas spp. and these oil-degrading soil bacteria. First, we classified these oil-degrading bacteria by the book called“Bergey’s Manual of Systematic Bacteriology.”We find three species of oil-degrading bacteria (P7A、 P7C、P7D) which are all grams-positive bacillus, possibly belonged to Aureobactreium、Curtobacterium、Cellulomonas、Oerskovia、Brochothrix、 Caryophanon. Second, in the study of the relationship between Chloropseudomonas spp. and the oil degrading soil bacteria, we found that Chloropseudomonas spp can considerably inhabit the growth of oil-degrading bacteria. Besides, there are also a great variety of interaction between three species of the oil-degrading bacteria. According to the result , the interaction might considerably affect the efficiency of oil bioremediation. Due to our analysis, we suggest that it is necessary to pay more attention to the interaction between bacteria when undertaking oil bioremediation.

Polysiloxane Elastomeric Lenses as Intraocular Lenses in Cataract Extraction

A polysiloxane elastomeric lens was formed by mixing a silicone elastomeric base and silicone elastomer curing agent. It was molded from a +100 glass lens attached to a milled Plexiglas mold. The changing focal length as a result of the application of different degrees and ways of applying strain was observed with the help of a diverging laser beam and 28 and 30- diopter lenses. The shortening of the focal length as a function of applied strain using weights was observed for two treatments namely low weight and high weight. The focal lengths were measured using a vernier caliper and an adjustable white board on which the laser beam was reflected. Data for the experiment involving weights showed that there is a general decrease in the length of the foci of the elastomeric lenses as more weights were added to the set-up. This can be attributed to the increase in curvature of the lenses as more weights were added. Data for the experiment involving spring balances showed that there is a general increase in the length of the foci of the elastomeric lenses as the spring balances are pulled harder. This can be attributed to the flattening or decrease in curvature of the lenses as the spring balances are pulled harder. A stretchable lens can be used to replace intraocular lenses in cataract extraction. By changing the focal length, the lens can work for a wide range of distances, and therefore serve as the definite solution to the development of cataracts and other conditions that affect visual activity.

生活中的碳-探討自製的活性碳之吸附雜質及竹炭屏蔽電磁波效應

有鑑於SARS 期間活性碳口罩因原料均從國外進口,而造成活性碳急需用時的短缺,於是我們的研究是以國內最常見的木材自製成活性碳,並探討活性碳對生活週遭常見物質的吸附能力。我們利用六種不同的木材配合兩種活性化方法來製成不同的十二種活性碳,觀察活性碳對有色溶液的吸附效果,發現不同的活性碳對不同的物質有不同的吸附效果。在定量實驗中,我們採用不同大小、不同性質的物質依次為氯離子、氨分子、葡萄糖分子及三氧化二砷等,用十二種不同的活性碳作吸附效果的比較,發現每種物質都有對其具有最佳吸附能力的活性碳。再利用電子顯微鏡觀察並測出活性碳孔洞的大小,將結果與活性碳對各種物質的吸附能力相對應而得知,【1】活性碳的孔洞大小與物質質點相容性大即得最好的吸附效果【2】雖然木材本身並不帶電,但其中所含的礦物質可能會具有電性,所以在必要情況下亦可將電性列入考慮。同時,在現代化的生活環境中,人們與電磁波的接觸已無可避免;而電磁波因頻率的差異而有不同的特性,因此對於人們的影響也不相同,新聞報導中常出現宣稱竹炭具有遮蔽電磁波的效果。於是我們深入地去探討竹炭對電磁波的影響原因。 在我們實際測量過程中發現,基地台、高壓電塔、行動電話和家庭電器所釋放之電磁波總和均在安全範圍之內。竹炭的燒製溫度須達550℃以上才可在內部形成具有導電性的石墨結構才進一步具有屏蔽效果。 ;During the ravage of SARS, a great amount of activated carbon was imported to Taiwan, leading to the shortage of actived carbon for emergent use in our country. In view of this phenomenon, we investigated six kinds of wood that are most commonon the market and processed them into twleve kinds of actived carbon. We found that different actived carbon has distinct adsorptive power on different substances by observing theadsorption in the colored solutions. In quantitative experiments, we applied substances of different sizes and properties (chlorine ions, ammonium ions, glucose molecules, arsenic(Ⅲ) oxide) to compare the adsorption of these twelve kinds of actived carbon. We found that each substance is adsorbed the most by a certain kind of actived carbon. Then we observed the apertures of actived carbon under stereoelectric microscope and contrast the result with adsorption. We had two following findings: Actived carbon has better adsorption if its apertures fit the adsorbate molecule well in size. Wood itself doesn’t have electric charge. But sometimes the minerals contained would enable it to have electric charge. We have to take the electric charge into consideration in the experiment if necessary. At the same time, in a modern life, the contact between us and electronic waves are not avoidable. Electronic waves with different frequency have varied characteristic and therefore cause dissimilar influences on humans. The news reports keep on showing the charcoal can shield us from electronic waves. Therefore, we want to find the causes why the charcoal affects the electronic waves. During the process of the research, we find that the total of all electronic waves released by electricity tower, mobile phones, household electronics are within the secure spec. The charcoal has to be burned higher than 550℃ and then it can generate the electric conduction graphite structure inside and then it can have the shielding function.

太陽能熱動力發電與效益的改進方法

在綠色能源中太陽能的利用充滿了無限的機會,其中利用太陽熱能發電的太陽能煙囪觀念有很大的潛力。在本研究中,我們以實驗的方法討論煙囪高度、入風口大小、管型等因素對solar chimney 效益的影響,發現就原先的觀念設計中,有相當大的改進空間。整體實驗而言,所改變的各項變數中,以管型之改變有最大的改進效益。就同長度直管與漸擴管而言,漸擴管在風速上有明顯改進效果,且以流速與截面積換算成效率,較原直管設計之效率高出約20 倍,因此推測漸擴管應用在現行之solar chimney 以改進效能是極有可行性的。研究中也發現煙囪管壁的熱傳導也會影響氣體的總體流動,使效率降低。相信此實驗之數據對日後嘗試對solar chimney 進行改進的研究者有相當之參考價值。Solar energy has a great market potential among many clean energies. The new solar chimney concept using solar thermal power in power generation may have a bright future. Experimental work was performed to study the energy conversion characteristics of a solar chimney. The air moving capability and the influences of chimney height, the shape of chimney and air entrance dimension were studied. It was found that there is a great room to improve the current solar chimney design and thus the efficiency. Overall speaking, the chimney pipe geometry may have the most significant impact on the improvement of performance. A diverged pipe configuration can induce nearly 20 times more flow than a traditional straight pipe. Another finding is the heat transfer effect on the chimney pipe may have the effect in reducing the flow. It is believed that the present study0 is valuable for those people in designing a future solar chimney.

人類粒腺體蘋果酸.活性中心輔.NAD(P) + 結合位置之探討

人類粒線體蘋果酸.可利用NAD+或NADP+為輔.,幫助腫瘤細胞獲得能量,但一般生理條件較傾向以NAD+為輔.。本研究將K346 修改成偏好NADP+之粒線體蘋果酸.家族中具有高度保留性的絲胺酸、及不具極性之丙胺酸,探討為何此酵素較偏好以NAD+為輔.。天然及突變株酵素的催化常數 (kcat)、基質Km 值、及抑制常數 (Ki) 測定結果顯示K346 之點突變不會影響基質Km 值,但K346S 之kcat明顯上升,繼而改變此酵素對NADP+之選擇性。本研究對於人類粒線體蘋果酸.催化機制的了解,有助設計具專一性的活性抑制劑,未來可應用於抑制腫瘤細胞能量來源,進而抑制腫瘤細胞生長。;Human mitochondrial NAD(P)+-dependent malic enzyme can help tumor cells gain energy, using either NAD+ or NADP+ as the cofactor, but prefers NAD+ as the coenzyme. By mutating the K346 to Ser, conserved in NADP+-dependent ME and to Ala with non-polar, we explore why human mitochondrial NAD(P)+-dependent malic enzyme prefers NAD+ as the coenzyme. We measured the proteins kcat, Km and the Ki values. The experiments showed that mutantions don’t affect the Km values, but K346S increased in the kcatvalue, transferring the coenzyme specificity to NADP+. If we develop deeper understanding of the human mitochondrial NAD(P)+-dependent malic enzyme, we can design a specific drag to inactivate the enzyme activity, and inhibit tumor cell growth.