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Tuning the Hydrophobic Nature of CNT Arrays with Micro-Patterning
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超省電!The Automatically Controlled Fan
本組改良第50屆國中組化學科「愈熱愈涼快」的實驗。除了沿用電解池的導電性會隨著溫度的改變的原理外,有以下改良: 1.電壓由15伏特提升至110伏特,以應用於一般電器使用。 2.將直流電改為交流電,並以銅棒對硫酸銅溶液通電,溶液濃度與電極因此皆不會減少,能長期使用。 3.利用溫度改變能使氣體熱漲冷縮的特性,製作氣體溫控升降儀,加大溫控效能,並達到自動化斷電目標。 4.最後,同時串聯四台風扇,以模擬教室環境用電,增加實用性與發展可能。
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要檢測膠體粒子是否存在於溶質中,並不能以一般的光學顯微鏡觀察得出,若是用廷得耳效應觀察光線散出的量決定,則將運用到大量昂貴的精密儀器,與繁複深奧的化學理論,本實驗主旨即在運用自製的簡單儀器測量待測膠體流經強磁場因磁電效應產生電壓,藉著改變沈降劑種類或劑量使電壓產生波動的現象,藉此評估各種沉澱劑對膠體溶液沉降效果好壞與最適當的劑量,並將此結果應用在實際污水處理作業的先期測試上。Wanting to know colloid particles exist in solute by a normal optical microscope is impossible. If we use Tyndall effect, to observe the quantity of dispersive beams, to prove whether colloid particles exist in solute, then we will use amount of expensive and precise apparatuses and even complex and abstruse chemical theory. The gist of this experiment is using simple apparatuses that made by us to measure the volt generated by colloid flowing through the strong magnetic field(magnetic-electric effect).Then we try to change the sort or dose of precipitant to let the volt undulate, so that we can compare the impression on precipitating of each of the precipitant and the most applicable dose. Finally the result can be applied to forward trial of practical sewage disposal system.
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本實驗在微小的測試環境下,以熱線風速計偵測壓縮空氣流經圓柱鈍體後方渦旋逸放的頻率,推導出雷諾數(Re) 與史卓荷數(St) 之關係。預期能利用有效雷諾數的概念,探討加熱圓柱流場的Re-St 關係,將25℃、50℃、100℃、150℃、200℃時的臨界雷諾數回歸成有效臨界雷諾數,導出Re 之分母---空氣黏度,以後便能以此不同環境溫度所對應之空氣黏度方程式,於各式環境下量得空氣的黏度。但因為在實驗中碰到了量測精度的限制,所以這個部份只有做現象的探討,並由觀測渦流逸放頻率發現到加熱圓柱確實可有效地穩定流場。未來也將會提高量測的精度,以期望能達到辨識氣體的效果。;The purpose of this experiment is to measure the vortex-shedding frequency while the compressed air flow over a cylinder by hot-wire anemometer and all of the experiment is set up at the small testing environment. By this way, we can find out the relationship of Reynolds number and Strouhal number. We expect that research the relationship between Re and St while flow over a heated cylinder by using the concept of effective Reynolds number. We can get the effective Re by curving fitting the critical Re at 25℃、50℃、100℃、150℃、200℃each and derive out the viscosity of the air. After this, then we can measure the viscosity of the air everywhere after knowing the viscosity with respect to the specific temperature. We only discuss the phenomena at this part, because the limitation of the accuracy of the instrument. We also observe that a heated cylinder can stabilize the flow field effectively by the vortex-shedding frequency. We are going to enhance the accuracy of the instrument and fulfill the gas identification.
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Reduction of free radicals and endotoxin by conjugated linoleic acid loaded in-situ synthesized poly
本研究首先利用NaOH 將PAN 薄膜改質形成PAA 水膠膜表面,進一步與異丙胺鍵結形成NIPAAm 結構,以做為藥物傳輸的載體。反應所得之PNIPAAm 薄膜其溫度轉換點為34 °C 其pH 敏感性介於pH 5 至10 之間,實驗進行進一步於34 °C將PNIPAAm 薄膜浸入共軛亞麻油酸(CLA)中,取出後置入4 oC 二次水中,最後測試經改質接枝後PAN 薄膜於膽固醇、三酸甘油酯的吸收效果,並以化學冷光儀分析改質接枝後PAN 薄膜其抗氧化效率。結果顯示改質接枝之PNIPAAm 薄膜於包埋CLA 其對於血液中膽固醇及三酸甘油酯有明顯的吸收效率,此外對血液中的自由基也有明顯較未改質之PAN 薄膜穩定的趨勢。A thin layer of poly(N-isopropyl acrylamide) (pNIPAAm) was synthesized in situ on the surface of hydrolyzed polyacrylonitrile (PAN) membrane. This thin layer exhibited both pH response due to the poly(acrylic acid) moiety and temperature response due to the pNIPAAm moiety. The swelling behavior of the membranes was evaluated under various temperatures and pH. The curve of the swelling ratio for the PAN-NIPAAm showed a lower critical solution temperature (LCST). Then conjugated linoleic acid (CLA) was loaded into the pNIPAAm layer. The effects of CLA on the blood coagulation and oxidative stress were evaluated using human blood. The level of reactive oxygen species (ROS) was measured by chemiluminescence (CL) method to evaluate the oxidative stress. Furthermore, the removal of bacterial endotoxin (lipopolysaccharide, LPS) by CLA-loaded PAN-NIPAAm was measured with ELISA. The results show that the LCST swelling curve was at 37°C. In addition, the swelling ratio increased by 71% when the pH increased from 5 to 10. The concentration of LPS can be reduced by CLA-loaded PAN-NIPAAm 2.1 and 1.2 5 times of that by unmodified PAN and PAN-NIPAAm membranes, respectively. In addition, the level of ROS against CLA-loaded PAN-NIPAAm was reduced significantly than that against unmodified PAN and PAN-NIPAAm. Therefore CLA-loaded PAN-NIPAAm membrane could offer protection for patients against oxidative stress and could also inhibit LPS for clinical applications
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Dynamic Geometry and Problem Solving
Within the framework of the new educational model for mathematics based on constructivism, results are presented of the design, application, and evaluation processes of a series of didactic sequences aimed at developing the student’s abilities for problem solving as part of the geometry curriculum for technological preparatory schools, using the Cabri-Geometre II software. In this case, subjects of study were ten newly enrolled students from CETis 18 preparatory school in Mexicali, Baja California, Mexico. The theoretical basis for this work is the constructivist approach, mainly emphasizing Mashbits views (1997) regarding problem solving. This didactic proposal was longitudinally applied in a quasi-experimental qualitative design under the following analysis categories: problem solving skills and the impact of Cabri- Geometre II in geometry learning. Recognizing the potentiality this research can have with the proper follow-up, it is intended to include it in the preparatory school curricula. For this purpose, teachers should be trained to focus their work on learning instead of on teaching. As a result of this, designing educational programs will require for teachers to become more knowledgeable not only in discipline, but in the use of computer technology, the teaching process, learning, and the students themselves. The final objective of this project is to instill educators to play this new role. As a final point, conclusions on various psychological, pedagogical, and technological aspects are given placing emphasis on the creation of learning situations with their appropriate theoretical support. Using the Cabri-Geometre II as a resource, these situations will provide geometry teaching with a more dynamic and interesting concept applicable to real-life situations.
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Salinity effects on Duckweed growth
The purpose of this research was to investigate the most favourable salt concentration that promotes growth in the Lemna minor plant. Lemna minor, commonly known as lesser duckweed, is found growing among other aquatic plants or massed together in still or slow moving fresh water, such as ponds and lakes, in warmer regions around the world.
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一. 此研究是探討物體自由搖擺的現象,單擺和複擺是在物理學上常見的擺動現象,都是一種固定支點的擺動現象,尤其複擺運動時,擺動物體受轉動慣性影響而造成支點的受力,為一種拘束的第一向後運動現象。而本研究在探討多自由度自由支點的單一方向度之擺動現象。二. 本實驗從這幾種方向分別探討1. 扇形體在平面上之擺動2. 平板在圓弧面上之擺動3. 扇形體在圓弧曲面上之擺動三. 經我們實驗研究結果發現,在地球重力場中沒有固定支點的搖擺現象,是受到下列幾種因素影響1. 搖擺形體的形狀,其質量慣性矩的影響。2. 擺動物體與接觸路徑的相互影響。3. 擺動質量對擺動的頻率影響很小。This research explores the phenomena of swinging objects--- simple pendulum andcompound pendulum, which are constantly observed in physics. The inertial moment of the swing produces pressure to fixed points of support on which the swings occur, especially in compound pendulum, which are classified as restricted single freedom. The study provided here explores the phenomena of the frequency of unfixed supporting points. The exploration of this research develops experimentally as follows: a. fan shaped objects swinging on the plane surface b. flats swinging on the arced surface c. fan shaped objects swinging on the are-curved surface An impressive conclusion that there is no swinging phenomenon of fixed supporting points in gravity field on earth is achieved from the above experiments. A number of factors influence the phenomena of swings: a. the shapes of swinging objects and the influence of mass inertial moment b. the interaction between swinging objects and interfacing paths c. little influence from swinging mass to the swinging frequency
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洗滌用的界面活性劑分散系,沾在吸管可吹成泡,沾在框上則生成特定形體的薄膜;兩種不同現象,依據各自的性質原理,分別設計為可測量的裝置,研討表面張力與濃度間的關係,發現『兩泡連通法』,測量的靈敏度較佳,並且;薄膜總面積法則會因為框的形不同,測得薄膜總面積與表面張力大小的變化趨勢不一樣,而且數據誤差都比『兩泡連通法』大。市售的洗劑有肥皂與合成清潔劑兩類,它們溶於水的分散系,表面張力與濃度大小的變化趨勢正好相反;肥皂的濃度愈大表面張力愈大,合成清潔劑的濃度愈小表面張力愈大。這種現象發生的原因,和分散質是否含苯環結構無關。用數位照相輔助毛細管上升法,觀測『兩泡連通法』標準液的張力與濃度關係,數據顯示兩泡連通法與毛細管上升法,兩者比較各種分散系張力與濃度大小的結果相同。因此,用『兩泡連通法』比較不同分散系張力大小是簡便生動的可行方法。The dispersion of surfactant used for the purpose of cleasing,if dipped on a blowpipe,can be blown into bubbles and,if dipped on a frame,will form a certain shape of membrane.For these two different situations,according to the principle of their quality,measuringdevices can be respectively designed to explore the relation of surfact tension to its concentrate.It is discovered that,with the measuring device of the Two Bubble Connection Method,the sensitivity measured is better;and that,because of the difference of the structures of the frames,the total area of the membrane and the change trend of the degree of the surface tension will also be different and the probable error of the measured digits is always larger and it is not easy to find regularity. For the two categories of dispersion,soaps on the market and synthesis detergent,when they are measured with the Two Bubble Connection Method about the relationship of their surface tension to the degree of their concentrate,the trend of change is exactly opposite.The surface tension and concentrate of the category of soap are in right proportion whereas,for synthesis detergent used for cleaning bowls and plater and washing clothes,when its concentrate is less,its surface tension is more intense.Based on the findings of this study,the concentrate and the change trend of the degree of tension have no connection with whether there is benzene structure in the solvent. With the Capillary Rise Method assisted by digital photography to observe the relation of the tension of standard solution to the concentrate,we have found that they totally correspond to the result measured with the Two Bubble Connection Method designed in this study.
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Anaerobic Respiration: A Novel Bioelectrochemical Copper Recovery System?
Increasing concentrations of copper in discharged effluents pose hazards to aquatic food chains. This project aimed to develop a self-sustained copper remediation system based on electrical and microbiological principles. The production of electrons during yeast fermentation was investigated to catalyze the reduction reaction of dissolved copper ions. An electrical circuit was designed to harness electrons produced from either a pure or mixed culture of yeast, and were compared for voltage outputs. This system utilized a combination of carbon cloth and copper wire as the electrodes, and a magnesium sulfate based electrolyte. The better-performing cell was subjected to copper reduction analysis, in which various initial concentrations of copper were examined. Further data analysis was carried out on the voltage outputs achieved with both the mixed and pure cultures of yeast, in which an average base line was established and voltage flunctuations were compared to that of the base line. In this way, it was possible to determine the amount and severity of each voltage flunctuation — thus demonstrating whether mixed or pure cultures of yeast produced more stable outputs. Throughout the experiment, self-constructed equipment, including arduino microcontroller moderated incubators and drip-feed systems were implemented to maintain an optimum yeast growth rate. It was found that mixed yeast cultures produced smoother electrical potential outputs in response to feeding and stress intervals. The copper recovery experiment was therefore conducted using the mixed culture. Through a series of conductivity measurements indicative of copper concentrations, metal recovery was successfully demonstrated. Trend line analysis indicated similar flunctuations between voltage output and copper recovery rates, demonstrating how copper was recovered as a result of electrons harnessed from the yeast culture. These findings can be applied to the development of an energy efficient and cost-effective copper remediation system for contaminated water effluents.
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台灣不同世代A 群鏈球菌對紅徽素抗藥性之研究
A total of 64 nonduplicate isolates of erythromycin-resistant (MIC, >1 μg/ml) Streptococcus pyogenes collected from 1979 to 2003 in Taiwan were evaluated. They were collected from three cohort period: 1979 –1989, 1990-1999 and after 2000. The in vitro activities of 10 antimicrobial agents were determined by the agar dilution method. Penicillin, cephalothin, cefotaxime, vancomycin, and ofloxacin were shown to be active against S. pyogenes isolates (100% sensitive). Erythromycin and azithromycin both had poor activities (MIC50s, 16 and >128 μg/ml, respectively; MIC90s, >512 and >128 μg/ml, respectively). The activities of tetracycline, clindamycin, and chloramphenicol against a significant number of these isolates were also limited. Among the 64 S. pyogenes isolates, 58% had constitutive resistance [cMLS], 40% had an M phenotype and 2% had an iMLS phenotype (inducible resistance [iMLS]). A substantial upsurge in the incidence of M phenotype erythromycin-resistant isolates was found with time for S. pyogenes (10% in 1979–1989, 48% in 1990–1999 and 65% after 2000). The erythromycin resistance genes in 64 isolates of the different cohorts were investigated by PCR. All cMLS phenotype isolates tested had ermB gene. The M phenotype isolates had only the macrolide efflux (mefA) gene. This study shows the secular changes of increasing susceptibility of S. pyogenes isolates to both erythromycin and clindamycin in Taiwan. The mechanisms of erythromycin resistance have changed from the predominance of ermB gene (cMLS) to mefA gene (M phenotype). 本研究是探討台灣自1970 年代末期以來不同世代A群鏈球菌菌株對紅黴素的抗藥性及抗藥基因特徵的演變。研究者收集台灣二十年前(1980 年代前後,第一世代)、十年前(1990 年代,第二世代)、)及最近(2000 年以後,第三世代)之A 群鏈球菌菌株共64 株,利用抗生素圖譜和雙藥錠擴散測試及聚合?連鎖反應(PCR)、和脈衝式膠體電泳研究A 群鏈球菌對紅黴素抗藥性的表現型及基因型特徵。結果發現第一世代的A 群鏈球菌對紅黴素最小抑菌濃度(MIC)值相當高,幾乎都是>512 μg/ml,90%為多重抗藥菌株。第二世代則相對有降低,在第三世代此現象更明顯,多重抗藥菌株為30%。在雙藥錠擴散測試結果,從第一世代來看cMLS 佔大多數(90%),M 型佔10%;第二世代cMLS 及M 型相當分別佔52%及48%;第三世代主要為M 型佔65%,cMLS 佔30%,iMLS 佔5%。利用PCR研究紅黴素抗藥性基因發現所有cMLS 菌株皆有ermB 基因,所有M 型菌株皆有mefA 基因,iMLS 菌株則有ermTR 基因。由本研究顯示在台灣A 群鏈球菌對紅黴素之抗藥性隨著不同世代有逐年改善之趨勢,由MIC50的降低可看出,菌株對紅黴素的敏感性提高,可為臨床治療之參考。
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Filtered Light Frequencies versus Pigment Frequencies
Purpose of the research Experiments were performed to determine if the frequencies of the colours of pigment differ from the frequencies of the colours of filtered light. The third experiment was performed to determine whether the different colours of filtered light have an influence on plant growth. Procedures Experiments I and II were performed in sunlight and the temperatures of different colours of paper, as well as a white paper underneath different colours of transparencies, were measured by means of an infrared thermometer. The Stefan-Boltzmann equation was used for calculations. Experiment III was performed by placing ten spinach seedlings under each of the Code 40 red, green, blue and black/white shade nets. The control, 10 spinach seedlings, had no Code 40 shade net covering. All these spinach seedlings were grown under similar conditions and harvested after 4 weeks. Data In Experiment I the yellow paper was the only colour that did not perform according to the sequence of the white light spectrum (ROYGBIV). The temperature of the different colours of paper determined the amount of energy that was re-emitted. In Experiment II it was determined that the primary colours red, green and blue, as well as yellow of the filtered light, performed according to the white light spectrum. In Experiment III the spinach plants underneath the blue shade net have the highest average fresh mass (g), as well as the largest average leaf area (cm2), while the spinach plants underneath the red shade net have the lowest average fresh mass (g), as well as the smallest average leaf area (cm2). Conclusions In Experiment I the primary colours of the white light spectrum are red, green and blue. When red and green are combined, yellow is obtained. Therefore the temperature of the yellow paper was lower than expected, because only blue light was absorbed, while red, green and yellow light were reflected. In Experiment II all the colours of the transparencies performed according to ROYGBIV. By comparing the amount of energy of the colours of pigment to the colours of the filtered white light spectrum, it became apparent that there is a difference between the frequencies of the colours of pigment and the frequencies of the colours of filtered white light spectrum.
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