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本實驗合成之奈米銀粒子產物分為水溶液與固態形式。奈米銀粒子水溶液態製造方法以多芽基之檸檬酸根離子當保護劑,再以NaBH4 還原生成奈米銀粒子。而固態形式之奈米銀粒子是先以四級銨鹽界面活性劑當保護劑,經過NaBH4 還原生成奈米銀粒子水溶液後,再用二氧化矽包覆奈米銀粒子,藉由高溫燒去保護劑,得到含奈米銀粒子之二氧化矽分子篩材料。 將含奈米銀粒子之二氧化矽分子篩材料產物浸在純水中,除了不會改變水溶液性質外,又能以分子篩通透的特性,讓奈米銀漸進地釋放出銀離子,而達到長效性抗菌效果。 至於具抗菌性棉衫或濾網的製作,則採直接浸泡在奈米銀粒子水溶液中的方法,使奈米銀粒子吸附於上,針對上述實驗非常成功,洗滌超過十次且放置時間長達一個月以上,其抗菌效果仍佳,表示此簡易法製成的棉衫或濾網具有長效性的抗菌功效,為本研究重大突破。 奈米銀粒子對環境的影響是利用黑殼蝦來測試,控制適當奈米銀粒子濃度,使黑殼蝦能生存,亦可達到水中殺菌的效果。本實驗為首次針對奈米銀粒子對環境影響的測試並獲得重大的成果。;In this study, two Ag nanoparticles samples including Ag nanoparticles in aqueous solution and in solid form were prepared. The Ag nanoparticles aqueous solution readily obtained from reduction of AgNO3 aqueous solution with NaBH4solution in the presence of the sodium citrate as protecting agent. To prepare the Ag nanoparticles@porous silica sample, cationic alkyltrimethylammonium surfactant was used as the protecting agent of Ag nanoparticles and template of the porous silica. The Ag nanoparticles@porous silica was synthesized via reduction by NaBH4, silicification in silicate solution and calcination for the removal of surfactant. When adding the Ag nanoparticles@porous silica, the property of the aqueous solution was not changed. In addition, the Ag+ ion was gradually released from the accessible silica matrix to achieve a long-lasting effect on anti-bacteria. To prepare anti-bacteria clothes and sieves, these objects were soaked in Ag nanoparticles aqueous solution. The Ag nanoparticles were spontaneously absorbed into the clothes and sieves. The anti-bacteria efficiency of the Ag-nanoparticles containing clothes and sieves still remains even after ten-time washing and a period of time longer than one month. These worthy results indicate that this synthetic method provides a simple way to prepare the long-lasting Ag-nanoparticles containing clothes and sieves for anti-bacteria application. To investigate the influence of the Ag nanoparticles on the environment, shrimps are used as testing objects. With a well control on the Ag nanoparticles concentration, the shrimps survived well and the bacteria content was reduced. It is the first time to have testing result about the effect of the Ag nanoparticles on the environment. Thus, this is the most remarkable achievement in our experiments.
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平面切立方體內單位立方格數極值之計算
我們先假設有一正方體及一截過正方體之平面,並設正立方體為一k*k*k 之立體。為計算平面截過之單位正立方體個數,我們必須先分別計算各層被切過之個數再將之相加,因此將各層面投影至同一平面,簡化為平面上之問題,並討論其性質/規律,計算平面截此正立方體之個數。如此,便可以一般化數學式計算平面截正立方體個數之問題。接著,用以上方法為基礎,討論各種平面切正立方體之類型,將被平面所截之單位立方體個數以電腦程式算出,觀察數字變化及其性質規則,並找出最大值發生之條件。 We initially supposed that there are a regular hexahedron consists of unitary n × n cubes and a plane which incises the regular hexahedron. To calculate the total number of the unitary cubes incised by the plane, we can first calculate them layer by layer and then sum them up. And further, we project each layer on the same plane, so the three-dimensional problem is simplified into two-dimension. By making use of the character which results from projection, we can easily calculate the number of the unitary cubes incised. Consequently, we are able to calculate them with a general equation. Afterward, we research each circumstance that the plane incises the regular hexahedron on the base of the mentioned methods. Calculate them with self-designed computer programs, and observe the regulation and change of the result. Furthermore, we can find out when it will achieve the maximum.
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蟋蟀聲音與行為的關係密不可分。取北部四種蟋蟀樣本,以數位錄音筆錄製及電腦軟體分析蟋蟀的聲音,並用PCR技術萃取蟋蟀的粒線體DNA(16S)加以分析,藉此和傳統的形態學分類相互比較。結果發現蟋蟀聲音的頻率特性中主頻率的差異在親緣遠近有關聯性,但聲音的時間特性方面則沒有特定關聯,不過聲學分析圖仍可作為單一種的鑑定指標。此外,研究發現此4種蟋蟀的聲音頻率範圍有重疊現象,但主頻率、脈衝比、唧聲率及唧聲長不同,推測雌蟋蟀應是綜合這些特性辨別同種。另一方面,以黑蟋蟀作為研究對象,進行干擾實驗,觀察並繪製出其聲音行為模式; 並將此作為對照,結果發現蟋蟀的生殖行為主要受到雄蟋蟀的聲音支配,而雄蟋蟀則以嗅覺辨別雌蟋蟀位置,決定下一步行動,與視覺較無關係。 Cricket's voice is closely related to the behavior. We select four species of crickets from the northern Taiwan to study the acoustic and mating behaviors. The digital sound recorder and acoustic software are used to analyze their acoustic characters. Furthermore, the PCR technology is used to amplify and sequence parts of mtDNA sequences and the results were compiled as the comparison to the traditional morphological character. The result shows that the resolution in acoustic characters of main frequency, pulse number, chirp rate, and the length of chirp are different among four species, though the minor frequency pattern is overlapping. Moreover, we find that frequency characteristic difference among four species is partly related to their phylogenetic relationship, yet is not seen in time characteristic. It is obvious that difference of acoustic behavior can be regarded as identified index among species. Results of acoustic analysis impel us to infer that the female crickets take the comprehensive acoustic behavior to distinguish their specific male. In addition, behavior pattern and model of Gryllus bimaculatus are established as the comparison of interfering experiment is undertaken. Which results suggest that the mating behavior in cricket is dominated by males’ acoustic behavior, and is initiated by male’s olfactory sense rather than that of sight.
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一般學生對於學校課程學習的負擔,再加上對本身的自信心不足,往往導致學生自己所「背」的東西不是十分確信是否有真正記進腦中,也常常困擾著他們。因此,引發本小組想設計一個可以自我評測且可以立即得到成績的輔助學習機;在研究過程中,本小組設計記憶學習機不但可以做到使用者自我評測的功能,還可以讓使用者馬上得到檢測的結果並且使用者可以回顧先前成績欄紀錄;記憶學習機經過本小組組員的辛苦孕育下誕生,本小組便拿著「它」讓班上同學認識,雖然「它」不是同學心中的最佳主角,但是同學卻一致認定「它」是『最佳伴讀夥伴』。本作品主要功能有:1.能調整使用者所要求的測試時問。2.該作品能記憶此次測試成績,以便和下次相互比較。3.依使用者的需求選擇中文、英文、數字及遊戲模式做記憶訓練。4.能有立即性的成效及回饋。 Due to the pressure of courses and lack of confidence, many students are often not sure of what they have recited on a lesson previously, which in turn always disturbs and cut down learning confidence of students. To eradicate the obstacles they encounter, we decide to research into this topic. A memory-based learning-aided machine is designed for students to self-evaluate themselves and to get the feedback at once. In the process of development, the memory-based learning-aided machine not only lets users practice the exercise of their own, but also is able to derive the outcomes immediately and retrieve the previous records effectively and efficiently. We strive to make this learning-aided machine at its best performance as possible as we can. Besides, the memory-based learning-aided machine provides the alternatives for the users to answer the question in a way that they like. For example, users can answer questions in English mode, can choose the limit time into test themselves in a time. In addition, the system can expand its material by inputting data into the knowledge base. By our group members' lasting efforts, the learning-aided machine was created, finally. According to the result of experiment that we applied to the classmates, we conclude that the memory-based learning-aided machine is the best assistant and learning partner for the students. We would like to introduce it to classmates and hope they will be interested in using it to enhance their learning motivation and performance.
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相剋作用是指植物在代謝過程中釋放出有毒物質以抑制本身或鄰近植物種子萌發及植株發育生長的過程。一般認為,榕樹是具有相剋作用的常見植物,但很少見到相關的文獻探討。本實驗利用榕樹不同組織萃取液,以小白菜、結球白菜與阿拉伯芥作材料,探討該萃取液對上述植物發芽與生長之影響,結果顯示榕樹葉萃取液所造成之影響較顯著,不同榕樹組織的萃取液、不同濃度的萃取液對不同植物所產生的效果不盡相同,針對不同生長期的植物進行處理所造成的影響亦有差異。進一步以管柱層析法與高壓液相層析法(HPLC)分離葉萃取液,結果發現以正己烷和乙酸乙酯75:25為沖提液的條件下,於HPLC的層析圖中分離時間約8分時所流出的物質具最明顯的抑制作用。電泳剖面分析顯示處理與未處理間有些許蛋白質條帶差異,此變化蛋白可能與植物幼苗對該萃取液之耐受性有關。利用核酸微陣列(microarray)對榕樹萃取液處理之阿拉伯芥植物進行基因表現分析,發現榕樹萃取液對植物部分基因表現也有促進和抑制的情形,經由基因體與蛋白質體分析法可推論出一些受影響之相關基因。 Allelopathy was defined as a phenomenon which certain plant species, by secreting metabolites to the environment, can suppress the growth of themselves, seed germination and/or growth of other plants in the same habitats. Banyan (Ficus microcarpa L.f.) is a plant species in our campus likely to have allelopathy effect. However, documents describing such action on allelopathy were rare. In this study, we applied the crude tissue extracts including leaves, stems, roots of banyan onto the germinating seeds of Pai-Tsai (Brassica rapa L.ssp.chinensis(Rupr.(Olsson))), Chinese cabbage (Brassica pekinensis Rupr.) and Arabidopsis(Arabidopsis thaliana, ecotype Columbia-0) to study the effects of such plant extract on the germination and seedling growth of other plants. It is found that allelopathic effects on seed germination vary among different tissues used for extract preparation. Different concentration of the extract also yield various degree of allelophathic effects. It is also noted that the application of extract onto the post-germinated sprouts has less effects on plant growth. The extract of leaves was subsequently chromatographed over silica gel using hexane/EtOH gradient solvent system and HPLC. The result showed that there was one fraction about 8 min in the chromatography of HPLC eluted with 25% EtOAc in hexane had the most inhibitory effect. SDS-PAGE analysis on the electrophoretic profiles of water soluble proteins has explored a different band pattern between the treated and non-treated sprouts. The observed band difference might provide a clue for exploring proteins which reacted differently upon the application of extract. DNA microarray analysis on the effect of banyan extract on Arabidopsis gene expression has also been employed to characterize genes responsive to the allelophathic treatment. Cross-comparison between the differential transcript and protein profiles will reveal key regulators in plants experiencing allelophathic condition. \r
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Promoting Metal Adhesion to Electrospun Fibers and olymer Thin Films with Gold Nanoparticles and Sup
As electronics continue to shrink in size, the cost and environmental impact of current methods of production are increasing dramatically. The purpose of this experiment was to lay the groundwork in another potential method of creating nanowires and printed circuit boards. We believe that through the exposure of supercritical CO2, metalized electrospun fibers with gold nanoparticles will have increased conductivity. In addition, the adhesion of metal to polymer thin films can be controlled with a poly (ethylene oxide) (PEO) mask on both silicon and Kapton substrates. This study found that a specific concentration of gold nanoparticles can make a solution of poly (methyl methacrylate) (PMMA) in chloroform that cannot be electrospun, spinnable. Scanning electron microscopy also confirmed that scCO2 smoothes the surface of the fibers and makes them more uniform. EDX analysis also found that exposure to scCO2 also removed all residues of solvent and cross.sectional transmission electron microscopy showed that the nanoparticles were conglomerated near the surface. In conclusion, scCO2 and gold nanoparticles respectively enhanced the morphology of the fibers and made the electrospinning process more robust. Cross.sectional analysis also showed that the nanoparticles attracted the deposited gold into the fiber making prongs reach from the deposition into the fiber, but there was no test to quantify the adbesion. Using the spray bottle test, the gold still remained on wires. The resistivity of the micro wires was extremely close to that of gold creating resistances within hundreds of ohms over hundreds of micrometers of wires. Thin Films masked with PEO were exposed to scCO2 and metalized with gold or copper. Atomic force microscopy analysis shows unique crystallization formations of poly (capro lactone) (PCL) after scCO2 exposure. ASTM standard peel tests determined that the process was successful with PCL thin films. On the Kapton samples, peeling patterns reversed when the thickness became too great to melt in scCO2.+ Through perfecting these processes, the electronics industry can continue in its miniaturization while the environmental and monetary costs.
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我的味噌湯-微小顆粒在液體中沈澱模式之觀察研究
The purpose of the research is to investigate the settling mode of the viscid micro-particle, such as the ones from the “Miso Soup”, in static liquid. We constructed the “constant temperature environment” by constant temperature trough and transparent glass trough. The data is gathered from pictures captured from DV and then analyzed by Media Player. We did a stability test prior to the start of the experiment and found the system with good stability. The results of the experiment are as followed: 1. The settling mode can be divided into four phases: (a) Initial accelerated phase (b) Maximum phase (c) Gradually decelerated phase (d) Stationary phase. 2. The lower the fluid concentration is in the fixed temperature: a. the faster its settling interfaces appears; and the deeper it becomes for the depth of its settling interface. b. the faster the maximum sedimentation rates of the settling interface becomes and the slower it appears. 3. At the fixed concentration, the higher temperature: a. has the bigger maximum sedimentation rates of the settling interface b. gets to the stationary phase sooner c. has shallower stationary settling interfaces d. the time when the settling interface appears is independent with the temperature 4. The shape of the container has no effect on the settling mode as the settling interface is always perpendicular to gravity field. 5. If we add salt into the liquid, the stationary settling interfaces of the result will be higher than non-added ones.本研究的目的在於探討味噌這樣的微小黏性顆粒,在靜止液體中的沈澱模式。運用恆溫槽與透明玻璃水槽所建構之恆溫環境透過數位攝影機,以電腦播放軟體於特定時間擷取畫面進行分析。在正式實驗前,進行了穩定性試驗,發現穩定性良好。實驗的結果發現:一、 沈降模式:可以分為四個時期,分別為(一)起始加速期(二)高峰期(三)逐漸穩定期(四)完全靜止期。二、 在固定溫度下,溶液濃度越低:(一) 出現沈降交界面的時間越短且穩定距離距液面越深。(二) 沈降面沈降速率最大值越大且出現的越晚。三、 在固定濃度下,溶液溫度越高:(一) 沈降面沈降速率最大值越大。(二) 沈降交界面完全靜止期出現的時間越短,也就是越快達到穩定。(三) 沈降交界面的穩定距離距液面越淺。(四) 沈降面沈降速率最大值出現的時間與溶液的溫度無關。四、 容器內部的形狀與沈降面的沈降行為並沒有影響,都是成與重力場垂直的水平線沈降。五、 添加食鹽之後最終穩定沈降面比同濃度同溫度的高了許多。表示添加了食鹽對於味噌溶液有阻止沈澱的效果。
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導電高分子在各面之應用非常廣泛,其中聚苯胺因價格便宜,製作簡便,使其應用潛力更為突出。聚苯胺在鐵系及非鐵系金屬之防蝕能力已被證實,但由於聚苯胺與金屬之附著力不良使其應用受到限制。本文以提高聚苯胺在有機溶劑中溶解度以達到和金屬有效附著增加其防蝕能力為主,而奈米粒子所具有的表面效應、小尺寸效應及宏觀量子隧道效應,可為研究目標之一。但由於高分子奈米微粒之製備仍屬有限,故仍在研究中。
\r The development and application of the conducting polymer poly-aniline is getting\r prosperous and popular. The capability of poly-aniline in corrosion protection has\r been proved. But due to the adhesion of poly-aniline on the metal is poor, the applications\r are restricted. In this paper, the authors utilized how advance the solubility of\r poly-aniline in organic solution to modify the adhesion of poly-aniline on the metal\r in order to improve the effect of the corrosion protection of poly-aniline in ferrous\r metal. And the nanoparticles have the special effects such as the surface effect,\r the small size effect and the macro-quantum channeling effect. It can be an object\r for research.
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NO.59-01 2020 FEB
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科學研習期刊目錄 本期專題 科學素養學習 自然科領域探究與實作課程協作平台之建置分享 | 吳仲卿 以開放性問題融入探究與實作課程 | 徐鏞元 發展探究與實作紙筆測驗與作答數據分析 | 何興中、李麗偵、林蓓伶、盧政良 素養導向探究實作課程之實踐與教學策略 | 謝甫宜 108課綱新型態課程-「探究與實作」之規劃與執行經驗分享 | 趙君傑 新課綱自然科學探究與實作的理念與實踐 | 簡麗賢 教學現場 一位高中生的電化學物理研究之旅—科學探究與實作的自主學習案例分享 / | 李柏翰 科學趣味競賽融入多元選修課程之高中教學現場經驗談 | 柯瑞龍 從生活到課堂--三用電表的教學示例 | 林宣安 追「風」逐「電」 -以風力發電機進行探究與實作 | 李宥霖 磁鐵雲霄飛車教學分享 | 廖進德 科學新知 2019諾貝爾物理獎介紹 | 吳俊輝 特約專欄 可可冰之跨域教學研究 | 劉淑雯、洪文徽 閱讀《禮記·月令》設計Reading-STEAM教學活動 | 古建國 歷史上的臺灣龍捲風 | 黃文亭 森棚教官數學題-交換糖果 | 游森棚 科普活動報導 Kiss Science— 科學開門 青春不悶 | 洪美慧 自然科學探究式網路競賽實例分享 | 黃真瑱、李伃芳、李奕賢 科教館GO好玩 女孩們一起動手探索科學趣 | 顏慈瑤、陳虹樺、蘇萬生、陳雪玉 總召集人的話
自2019學年度實施的12年國教自然科學領域課綱,強調以增進學生科學素養作為自然科學課程發展的目標。本期特別以「科學素養教學」為專題。
「本期專題」單元共有六篇文章,〈自然科領域探究與實作課程協作平台之建置分享〉一文分享建置「自然科領域之探究與實作協作平台」的概念與做法。〈以開放性問題融入探究與實作課程〉一文分享台師大物理系利用開放問題進行探究與實作課程(簡稱物理思辨課)的經驗。〈發展探究與實作紙筆測驗與作答數據分析〉一文介紹數學創造力的相關理論與研究、教材與教學策略以及教學實踐。〈素養導向探究實作課程之實踐與教學策略〉一文從數學角度介紹統計與資料科學背後追隨的人工智慧之夢。〈課綱新型態課程-「探究與實作」之規劃與執行經驗分享〉一文討論向銀行「借錢」買房子後,如何「還錢」最划算。〈新課綱自然科學探究與實作的理念與實踐〉一文討論「教學現場」單元刊登五篇文章,〈一位高中生的電化學物理研究之旅 —科學究探與實作的自主學習案例分享〉一文利用小四學生學習長方形和正方形的周長與面積單元,解說該如何讓學生學得完整的周長與面積概念。〈科學趣味競賽融入多元選修課程之高中教學現場經驗談〉一文介紹數學奠基活動國中組中的「矩形拼板」桌遊活動。〈從生活到課堂--三用電表的教學示例〉一文利用類似雞兔同籠問題,說明嘗試錯誤、有規律嘗試錯誤、邏輯推理、代數解法之間的關聯及重要性。〈追「風」逐「電」-以風力發電機進行探究與實作〉一文解說如何藉由小五「多邊形」的學習,引導小六連結「逼近」概念以及先備學習經驗,讓圓面積的學習更有脈絡性。〈磁鐵雲霄飛車教學分享〉一文分享作者多年來帶領高中生從事專題研究,進而形成科展作品的過程。
「科學新知」單元刊登兩篇文章。〈諾貝爾物理獎介紹—從系外行星到宇宙奧秘〉一文帶領讀者面對「颱風假」課題,省思應如何看待及抱持何種態度才不致失焦。〈可可冰之跨域教學研究〉一文則介紹臺灣在集集地震後在地震測報工作的進展。
「特約專欄」單元刊登三篇文章,〈閱讀《禮記·月令》篇設計 Reading-STEAM教學活動〉一文拋出有關兩個三角形全等條件的問題。〈歷史上的臺灣龍捲風〉一文分享走讀日本福音館《かがくのとも》(科學之友)月刊50周年展後對月刊科學繪本的介紹與推薦。〈森棚教官數學題〉一文則提出對PBL-STEAM課程發展與教學活動設計的見解。
「科普活動報導」刊登兩篇報導:〈Kiss Science—科學開門 青春不悶〉透過2019年指導學生參與自然科學探究式網路競賽得獎作品實例,說明進行探究活動的歷程;〈自然科學探究式網路競賽實例分享〉報導國研院善用其強項和方式讓孩童愛上科學的展覽活動。
本期「科教館GO好玩」單元刊登〈女孩們一起動手探索科學趣〉一文,則介紹如何透過有趣的卡牌桌遊,讓民眾甚至年齡更小的學童曉得核災的知識。
總召編輯委員 - 李隆盛 關於本刊
出版單位:國立臺灣科學教育館
發行人:陳雪玉
總召集人:李隆盛
編輯委員: 物理科吳仲卿/陳耀榮/李柏翰/盧玉玲
| 化學科古建國/許良榮/王伯昌/林如章/周金城
| 生物科王美芬/蕭世輝/陳建志/郭淑妙
| 地球科學許民陽/王郁軒/李文禮/謝隆欽 科技科張玉山/汪殿杰/林育沖/趙珩宇
| 數學科李源順/鄧家駿/溫世展/張宮明
| 跨領域學科李名揚/連信仲
| 特約專欄 游森棚/黃琴扉/劉淑雯
策劃:曾聰邦
主編:錢康偉
本月專題特約主編:吳仲卿
編輯:吳郡怡
網頁設計編輯:曾怡/施曉恬
投稿規範請來信詢問:article@mail.ntsec.gov.tw
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聽聽貝多芬作品的下一代:將碎形及基因演算法應用於數位音樂產生器
本研究整合了碎形圖形的迭代運算方法與基因交配觀念來達到音樂創新,並透過音樂和諧性判別機制來提高創新音樂的悅耳程度。利用基因觀念之交配的方法來解決長短的問題。這個方法是把原始音符輸入後,找出它們的中心點,以這個中心點為準,其他的音符按照一定比例向外延展,成為新的迭代點。再利用這些迭代點,迭代出新的音符。把製造好的音符染色體放置到交配池中,以隨機的方式在交配池中選取其中之一個染色體進行交配的動作,此二音符染色體會交換彼此的基因,產生下一代新的代表音符長短之染色體,隨後以「模仿母體判斷式」來判斷這新一代的音樂是否與母體音樂相似,藉此淘汰掉「不肖的」下一代,而若新一代與母體的相似程度高的話,它的悅耳性相信也會相對提高。最後把這些技術應用於數位音樂創作,以衍生新穎應用與創新的結果。Fractals can be produced by IFS (Iterated Function Systems). By iterative computation of many times, we can obtain the similar graphics. In my research, the methods to generate the iterative algorithms were presented. In addition, I would discuss the regularity and the content as well as the properties of those digital patterns. At last, the advanced application of fractals to digital music pieces was presented. The program took a note of several measure of music as the beginning point, and made the IFS calculations for each new note in each measure. But there was no difference in beats if you just make the IFS iteration. So I changed the beats with genetic crossover method. In this research, the expression of the DNA to each beat of note was adopted. The same way, it took a note as a beginning point. And the system obtained the new DNA from the old notes for new ones randomly. After producing the new pieces of music, I want to know if it is good to listen. So I used the algorithm that checks the simulation to the shape of mother music. If its shape is similar to the mother music, the probability that the new music is pleasing may even increase. That would make a piece of brand new music. What I want to do in this research is improve the multiformity of music and find what the relationship is of ‘good music’ and mathematical algorithms
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本研究欲探討垂直水柱遇障礙物成節的形成機制。以數位照相機、光電計時器等進行觀測。 實驗結果如下: (一)因往返水柱波速不同,而且節無波腹大幅振動現象,故節不是駐波現象。 (二)細針插入水柱表面時,當針上方超過某長度後,針下方產生V字形震波。但不論針相對水柱的速度是否超過波速,針上方都有節,故不是震波所產生的現象。 (三)根據水波槽模擬實驗,不論木條是否超過波速,木條前方均產生波紋。木條前方的水受到木條推動,往前方加速,因此顯現出波紋了。 我們認為,在水柱中所看到的節,不是震波或駐波,而是相對於木條往前傳遞的波。波源是撞擊物,改變了水柱表面的壓力,而成為波源,水柱的水因受撞擊,某個範圍內流速會小於波速,使得撞擊物前方存在波紋。This experiment uses digital camera and photoelectric timer to discuss the mechanism of causing spouts to form nodes on its surface. Because the downward wave velocity of the spout is different from that upwardand there are no significant vibrations of antinodes, standing waves are not the mechanism of causing nodes. In the experiment of inserting a needle into the spout, we found out that while the needle was inserted above a certain length of the spout, v shaped bow waves emerged. However, no matter the velocity of the needle related to the spout is over the wave velocity, there are always nodes above the needle. Therefore, bow waves are not the mechanism of causing nodes. According to the ripple tank simulating experiment, no matter whether the speed of the wooden stick is faster than the wave velocity or not, there are always waves forming in front of the wooden stick. The wooden stick pushes water in front of it and causes the water to accelerate forward. Therefore, waves appear. We think that the nodes we see on spouts are neither standing waves nor bow waves. The nodes are rather caused by the relatively moving wooden stick. The object, which impacted the spout (wooden stick), changed the pressure of the spout’s surface and became the source of wave. Because of the impact, the velocity of the water current of a certain area became slower than the wave velocity and causes nodes forming on the surface of the spout.
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我們在校園內設置兩樣區,從2007 年4 月至2007年6月,共調查9株姑婆芋,93朵佛焰花,以瞭解姑婆芋生活史、傳粉昆蟲生活史及兩者之間的互動關係。 姑婆芋在11 月至7 月花期時會不斷產生佛焰花苞,剛冒出的花苞經過1到3天後,雌蕊漸成熟,佛焰苞會漸漸展開,開始產熱及一些特殊氣味,吸引果蠅科未知種的蠅類傳粉。當胚株受粉後,佛焰苞頸部會閉合,迫使傳粉昆蟲會往上爬到雄蕊部位攜帶花粉,飛至另一株姑婆芋雌蕊上傳粉,因此姑婆芋與傳粉昆蟲之間具有互利共生的關係。佛焰花序主要產生氣味的部位是在附屬物及雄部,而佛焰苞則可以幫助吸引更多傳粉昆蟲。佛焰花序的附屬物及雄部相對溫度較高,可能具有產熱以吸引傳粉昆蟲的功能。 ;Our study started from April, 2007 to June, 2007. We observed a total of 9 Alocasia odora and 93 spathes to help understand the life cycle of these understory clonal herbs, its pollinators, and the relationship between them. Alocasia odora produces spathes continuously during inflorescence. In the female phase, the pistillate part of the inflorescence ripens and an opening appears at the spathe, heat and a special odor is produced to attract pollinators of Drosophilidae. When the ovule is pollinated, the male phase begins and the opening encloses, which forces the pollinators upwards to the staminate part to carry its pollens, and then fly to an other Alocasia odora, Heat and the special odor are produced by the appendix and the staminate part of the inflorescence, and the spathe can increase the number of pollinators attracted. The relationship of mutualism between these two species contribute to the study of coevolution.
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