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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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線上教學資源
高中數學科展經驗談 —數學探究的樂趣
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本研究將在來米粉、糯米粉、蓬萊米粉和糙米粉等米穀粉加入麵粉中做米饅頭,探討直接法與中種法所做各種不同比例米穀粉饅頭的差異,找出品質最佳的米饅頭。 研究發現:直接法米饅頭在糯米粉20%〜50%時,會Q軟有嚼勁,口感佳。蓬萊米粉米饅頭在鬆軟度和彈性方面品質最佳,可以加到40%。糙米粉米饅頭在鬆軟度和彈性方面次於添加蓬萊米粉,可以加到40%。在來米粉米饅頭,鬆軟度和彈性最差,不可添加超過40%,添加超過40%時,饅頭會變得乾、硬,易龜裂。 中種法米饅頭中,糯米粉米饅頭在鬆軟度和彈性方面品質最佳。由於中種法的麵糰膨脹力較強,饅頭組織變得柔軟細緻,口感好。因此,除了在來米粉50%的口感硬,不適合以外,其餘米穀粉皆可製作添加20%~50%的米饅頭。
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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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爸爸有香港腳,醫生說那是黴菌引起的;哥哥手上長了汗斑,醫生說那也是因為黴菌才變成這樣的。爸爸腳上長得是黴菌、哥哥手上也長有黴菌,我們人的身上真的有黴菌嗎?它們長得是什麼模樣呢?想起五年級的自然課「顯微鏡下的小世界」單元中,曾利用顯微鏡看過生長在食品與物品上的黴菌、以及學習到顯微鏡的使用方法。隨機取樣收集 30 個人身上 5 個部位的皮膚、指甲和頭髮,共計 150 個樣本,以 20%氫氧化鉀溶液做初步的黴菌篩檢,發現這些樣本中,身體皮膚長黴菌的人,他們最常長黴菌的地方是腳掌,其次是跨下,腋下最少。從初步篩檢中,由有發現黴菌的樣本做進一步的黴菌培養,得知腳掌中最常見的黴菌為絮狀表皮癬菌,跨下最常見的黴菌是石膏樣毛癬菌,腋下常見的黴菌則是石膏樣毛癬菌和絮狀表皮癬菌,頭髮中最常見的是犬小芽孢癬菌,指甲中較常見的黴菌則是絮狀表皮癬菌和紅色毛癬菌。研究環境和身體黴菌生長的關係,發現冷的溫度會抑制黴菌的生長,但是不能殺菌;水分則是維持黴菌生命所不可或缺的要素,如果環境乾燥,黴菌就會減少、死亡。在抑制黴菌的實驗方面,發現醋、米酒、檸檬汁、鹽水會使黴菌稍稍增加;精油、肥皂水、雙氧水能抑制黴菌,但殺不死黴菌;藥用酒精和優碘有稍微殺黴菌的效果,香港腳藥水和抗頭皮屑洗髮精則能有效殺死黴菌。
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去年,升上了三年級,開始練習寫毛筆字「書法」是我們的國粹,同學們學得十分認真,但是一不小心,就弄得頭黑手黑連衣服褲子都黑了,上學期老師准許我們用原子筆寫作業,手和衣服也時常被原子筆沾得藍一塊、紅一塊,洗都洗不乾淨,真使媽媽和我們頭痛極了,於是請教老師,怎麼洗去墨汁和原子筆汁?老師說這是一個好問題,就讓我們一起來做研究吧!
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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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在家裡的廚房、浴室之牆壁還有學校公廁以及排水溝附近,常發現有一種不知名,看起來有點像小蒼蠅又有點像是小飛蛾的昆蟲,經過判斷此種昆蟲為蛾蚋,是害蟲的一種,其佈滿細毛的身軀,可能藏有散布疾病的危機。本實驗即是以”蛾蚋”作為研究對象,首先先了解並記錄其生活史,再以其幼蟲為對象,試驗在不同清潔劑的處理下對幼蟲的影響。藉此推斷在自然狀況中,幼蟲是否能生存在會出現各種清潔劑的積水環境中,並期望能對蛾蚋有更深的認識,提供日後防治上的參考。實驗結果可以知道蛾蚋是屬於完全變態的昆蟲,整個生命週期約為一個月,但會隨溫度與食物量而有所增減。在感受性實驗中可以發現,測試試劑中的漂白水與潔廁劑對幼蟲的生存造成較大的影響,在低濃度處理下(0.125%)即可讓幼蟲死亡,但幼蟲對洗潔精的感受性較低,以50%的洗潔精處理皆至少能夠存活6個小時。一般而言,家庭或學校使用清潔劑時,濃度並不會太高,而實驗結果顯示當清潔劑在濃度不高且短時間內並不會對幼蟲造成太大的影響。水溝中除了有這些清潔劑外,豐富的有機質是牠們重要的食物來源,所以在能忍受清潔劑的威脅而又有食物來源之下,如不特別對環境做較徹底的清掃,難以杜絕此害蟲的存在。
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