化學

光催化氧化反應以半導體金屬氧化物為催化劑，進行有機性空氣污染物之快速分解反應。其原理係將半導體材質（如：二氧化鈦，TiO2），在適合之光能量照射下，將半導體激發成為具有氧化/還原能力之催化劑，可加速氧化還原反應之進行，迅速分解有機污染物。 研究動機在於利用TiO2在紫外光的照射下，將H2O 分解產生自由基，使其和水中的重金屬離子進行氧化還原反應，期待可以還原水中的重金屬藉以降低水中重金屬離子濃度，同時藉由使用界面活性劑對奈米微粒具保護作用，可回收重金屬奈米微粒。 由實驗結果得知在紫外光照射下，TiO2 使用量0.5 克，AgNO3(aq) 0.01M，照光24 小時其電導度值上升最多且在溶液表面觀察到銀白色銀金屬薄膜生成而所測得銀金屬析出量明顯增加。探討超音波振盪對TiO2還原力的影響得知，超音波震盪的時間越久，所上升的電導度值愈多。 探討常見的界面活性劑（陽離子型及陰離子型）對TiO2還原力的影響：從數據中可觀察到，加入陰離子界面劑時，電導度值明顯上升；而加入陽離子界面活性劑後，電導度值迅速下降，照光後電導度值也不理想。 探討日光及不同頻率的紫外光照射光源對TiO2還原力的影響：發現紫外光的波長愈短，銀金屬析出的量愈多。 探討除氧處理之溶液對TiO2 還原力的影響得知，除氧處理後所配製的AgNO3（aq）0.01M， 經照光24 小時後電導度值明顯上升，且在溶液表面觀察到大片銀白色銀金屬薄膜生成而所測得銀的析出量也大幅增加。 ;In the experiment, we used the properties of T i O 2 that can catalyzed by UV rays and breaking the molecules of water and produce free radicals, which free radicals can redox metallic oxide as accelerator to analyze organic pollutant briskly. We use different shinning time and to find the best effect of the redox reaction . So we want to use this attribute to begin the redox reaction with the metal ion (for example: Ag＋) in water, expecting to reduce them. And then we can use this method to recycle the metal and to reduce the pollution in rivers. Throughout shining UV rays in 24 hours, we can find out the best effect of TiO2 reducing the metal ion solution. We can also find that we use ultrasonic first; the more redox it will have. In this research ,we can observed that if we put more anion surface-active agent, the more redox it will have. We find the effect of UV rays is better than visible light. The most important is that we deoxidize the metal ion solution, we can get the best effect of the redox reaction . In our research，we can't get the satisfing result of the copper sulphate (CuSO4) by TiO2 accelerating the redox reaction under UV rays.

超導體具有兩大特性 - 抗磁性及零電阻，若善加利用便能大量減少能量損\r 失。不過目前發現的超導體有的結構太複雜，其他則是臨界溫度太低。一年前科\r 學家發現不同於以往銅氧組成的鐵基超導體（FeSe），結構簡單但其臨界溫度仍\r 然太低。故我們利用原料濃度比例不同的Fe 及Se 以TOPO 熱熔法析出奈米顆\r 粒，分析其超導性質。結果顯示Fe 比Se 難析出，故Fe 濃度應比Se 多，且在油\r 性水域中較好混合。

The purpose of this project was to create a detection device for alcoholic drunk condition in human by using the principle of vapor pressure difference between breath samplings from normal and alcoholic-drunk men. The work comprises of three major steps. The first task was an experiment to determine an average air volume that can be fully blown out from the lungs of non-drunk people as a control. Twenty adult Thai volunteers weighing between 50 - 80 kg (average 59 kg) were used. The average blown out air volume was found to be 369.9 mL, with the range in values from 340-400 mL (sample size N = 20, SD = 15.47). The second task was an experiment to measure relationship between the blown air volume (100-700 mL, both from alcoholic-drunk and control groups of people) and the resulted vapor pressure by using manometer. The vapor pressure of normal breath increased from 400 to 1,600 newton/m2 with increasing blown air volume, whereas that of the alcoholic-drunk was found to be 600 to 1,800 newton/m2. The last task was to create a detection device prototype to gauge the alcoholic content in the human body from the breath. Air volume of 300 mL was arbitrary chosen to trigger lighting up of indicator lamps. The breath samples of low vapor pressure (low amount of alcohol, 21.12-44.00 mL, equivalent to 14.00-29.17 mg%) would trigger a green lamp to light up. A moderate vapor pressure range (medium amount of alcohol, 88-132 mL, equivalent to 58.33-87.57 mg%) would trigger green and yellow lamps to light up while a high vapor pressure (high amount of alcohol, 250 mL, equivalent to 165.72 mg%) would trigger green, yellow and red lamps to all light up. None of the three lamps would light up from (non-alcoholic) breath of control people. This device has also been tested to external group of volunteers. The work in this project has successfully demonstrated a useful application of simple principle in chemistry on partial vapor pressure.

本實驗在探討，當金奈米粒子和植物中的葉綠素產生鍵結作用力時，能量轉移的結果是否能幫助葉綠素激發電子。經由兩者混合後光譜的變化,發現兩者之間發生能量轉移。為探討此轉移現象和濃度的關係，我們將大小不同的金奈米和不同毫升數的葉綠素作用，並將其結果和金奈米與葉綠素的吸收強度和作比較，使用正規化的計算方法算出比值，由此看出兩者之間能量轉移的效率。當金顆粒約大於30nm時，正規化的數值隨的葉綠素濃度的增加而變大；而當金奈米顆粒約小於30nm時，則隨著葉綠素的增加而變小。Much attention is currently focused on chromophoric molecules because they can not only mimic natural antenna systems but also exhibit unique optical and physical properties. Chlorophyll , produced by extracting from green leaves, has electrostatic interactions with Au nanoparticles through carboxyl groups. Herein, we report the charge transfer between chlorophyll and Au nanoparticles using UV-vis electronic absorption spectroscopy. The efficiency of charge transfer from chlorophyll to Au nanoparticles was estimated by the normalization of Q-ban absorption intensity. From the observation of absorption intensity versus concentration of chlorophyll curves, we find that the efficiency of charge transfer is increased while the size of Au-particle is larger than 30nm, but decreased while the size smaller than 30nm.

In the last two decades, there has been increased interest in the utility of quantum scale semiconductors. These fluorescent single crystals can be as small as 1 nm in diameter, and their size and shape has been shown to be controlled by the duration, temperature, and ligand molecules used in their synthesis. Quantum dots, provide clear benefits over the organic dyes currently used for tracking biological processes. Yet, as the production of quantum dots is often very costly, the search continues for finding an industry-ready synthesis for a quantum scale semiconductor which would have high yield, optimal durability, high luminescence, and a broad absorbance range. Silicon, in particular, has been of great interest as it is the second most abundant element on the Earth’s crust and is generally a bioinert and electrochemically stable element. We report the synthesis of water-soluble, luminescent silicon nanoparticles with potential applications to bioimaging. Through a solution state top-down approach, the synthesis of hydrogen capped silicon nanoparticles was achieved in various organic solvents. The surface of the nanoparticles was capped with the functional organic molecules rendering the Si-QDs both air and water stable. Cell studies performed with our silicon nanoparticles and human monocytes show the direct applications these particles could have for tracking biological processes and the progression of cancer in the human body. In attempt to shift the luminescence of these particles, alterations of experimental methodology was also explored in the areas of reaction solvent and heating time. Through these changes, shape control of silicon nanoparticles was achieved in the form of silicon nanorods. The synthesis of this new shape of silicon at the quantum scale was confirmed by ultraviolet spectroscopy, photoluminescence, and transmission electron microscopy. The results of this study indicate that the use of silicon nanocrystals for biomedical applications is feasible.

Smoothened (SMO) is a critical component of Hedgehog (HH) pathway that is essential for stem cell renewal and is dysregulated in many cancer types. SMO is a seven transmembrane domain protein with three intracellular loops. Primary structures of SMO intracellular loops are unique and very much conserved among the species, which is indicative of significant and unique roles in intermolecular or intramolecular interactions. The hypothesis was that synthetic analogs of SMO intracellular loops may function as HH pathway inhibitors. Derivatives of second intracellular loop were synthesized utilizing automated solid phase peptide synthesis based on Fmoc chemistry. Peptides were purified by HPLC and there anti-proliferative activity tested on melanoma cells by MTT assay. Targeted libraries of second loop derivatives of varying length helped to identify compounds that inhibited the growth of melanoma cells in vitro with IC50 in nanomolar range. The most potent of antagonists obtained is the palmitoyl derivative of the Nterminal half of the loop, and is 12 residues long. Lipidation proved to be critical for the activity. Remarkably, retro-inverso versions of the peptide, in which all amino acids are in D-configuration, are even more potent and have IC50 in subnanomolar range. Circular dichroism studies proved that the peptides are folded both in aqueous solutions and in the presence of lipids mimicking the membrane environment. They also suggested that retroinverso analogs have a different fold, which may contribute to higher activity. The new compounds are promising drug candidates and present convenient tools for solving the\r mechanisms of hedgehog signaling.

1. Purpose of the research: Recovering bioethanol from fruit wastes by using brewing yeast and enzyme Viscozyme L\r 2. Procedures: Four different experiments were conducted in our project.\r Experiment-1: Samples in RM by the addition of only S.Cerevisia.\r Experiment-2: Samples in RM broth meduim by the addtion of 100 μl/g ViscozymeL and S. Cerevisiae\r Experiment-3 : ViscozymeL with different concentration\r Experiment-4: to determenine whether the enzyme with high concentration inhibited the fermentation.\r Analysis of ethanol: HPLC method was used for the analysis;\r HPLC method: (high performance liquid chromatography)\r 3. Data\r HPLC measured initial and final concentrations of glucose and ethanol by the addtion of S. Cerevisiae.\r Initial glucose concentration and final ethanol concentration was the highest in Grape pulp 12 and 9 g/L respectively. Despite the glucose concentration was the lowest, the ethanol concentration was quite high (7 g/L) in the mixture with orange. The lowest ethanol was produced in the mixture with pomegranate.\r Concentrations of ethanol and glucose from the samples in RM broth meduim by the addtion of 100 μl/g ViscozymeL and S. Cerevisiae\r After the 24 hour incubation by the addition of enzyme glucose concentration incresed by 1, 4 and 2 respectively in sample 1, 2 and 3. The ethanol concentrations in comparison to first experiment were higher especially in the sample1 (grape pulp).\r Effect of ViscozymeL with different concentration on glucose production.\r The glucose concentration generally increased by the addition of 200 micro L of enzyme as the time proceeded. In grape pulp sample glucose concentartion didnt increased by the addition of 500 micro L enzyme.\r The remaning glucose and produced ethanol concentrations by the addition of viscozyme L with two different concentartion and S. Cerevisiae\r As the concentartion of enzyme added incresed the amout of ethanol also inreased in sample 2 and 3 but in the sample 3 the fermentation was inhibited.\r 4. Conclusions\r In this study sugars in fruit wastes that are regularly not recylecled were fermented successfully into ethanol by using S. Cerevisiae.\r Generally we get more ethanol from the samples when the enzyme was used. As the graph5 shows the ethanol concentration generally increased as the enzyme concentration increased. But especially in the sample1 (mixture with pomegranate) at 200 and 500 micro liter concentrations, ethanol production were 2 and 0 g/L respectively. In the light of this daha we conluded that the enzyme with high concentartion might inhibit the fermentation. When the activity of enzyme was inhibited by keeping the pretreated enzyme in boiling water, the fermentation restarted and recovered more ethanol; 8 and 12 g/L at the enzyme concentration of 200 and 500 microliter respectively.

Nano-sized calcium phosphate was used in the synthesis of starch-based composite plastics to provide a cheap but sturdier biodegradable alternative to petroleum derived plastics used in film packaging. Nano-sized calcium phosphates were produced from the precipitation reaction of calcium nitrate tetrahydrate (Ca(NO3)2 ‧ 4H2O) and phosphoric acid (H3PO4). The nanoparticles were co-extruded and molded with thermoplastic starch (TPS) at ratios of 0%, 1%, and 5% by mass. Tensile strength and elongation percentage of the resultant composite plastics were tested in three replicates. The results show that there is a significant difference between the tensile strengths of the 0% and 5% calcium phosphate composites at a 5% level of significance. The trend between the composite’s tensile strength and percentage calcium phosphate follows a geometric progression, enabling a projection for the 10% nano-calcium phosphate to have a tensile strength of 10 MPa, the average tensile strength for low-density polyethylene (LDPE). This shows that it is feasible to synthesize a 10% nano-calcium phosphate-TPS plastic that can be a viable substitute for LDPE plastics in film packaging, paving the way for the commercialization of starch-based plastics. The use of biodegradable plastics with improved physical characteristics will lessen consumer dependence on petroleum derived plastics and solve the environmental issues brought about by the use of such plastics.

瓦斯熱水爐使用大火時廢氣的CO 濃度非常高是導致一氧化碳中毒事件的關鍵原因，要解決這個問題觸媒轉化是一種可行的方式。影響觸媒性能的因素中以活性中心的種類最為重要，我們發現對轉化一氧化碳為二氧化碳的反應而言鈷有最好的催化效果，其次分別為：鎳、銅、鐵。最好的載體是三氧化二鋁，鈷的含量使用10％，煅燒溫度使用300℃可兼顧性能與成本。 本研究中所研發的 Co/Al2O3 觸媒具備有實用的潛力，可以在空間速度高達1000min-1 的情況下將濃度14,632ppm 的CO 百分之百轉化為CO2，而僅需233℃的反應溫度。因此，應該可以應用在瓦斯熱水爐上以降低一氧化碳中毒的風險。 The incorrect usage of a natural gas powered water heater always generates high carbon monoxide concentration in a closed environment. The dangerous CO gas can be fatal to the careless user of the water heater. Catalytic conversion of CO to CO2 can be a convenient method to solve this problem. The effect of the support, the supported metal, loading of the metal, reaction temperature, gas concentration, and reactants flow rate on the performance of the CO oxidation catalysts have been investigated. X-ray diffraction, gas adsorption and Infrared spectroscopy were applied to study the characteristics of catalysts. A 100% conversion of CO to CO2 can be achieved when 1.46% CO/6% oxygen/N2 reactants was catalyzed by a 10% Co/Al2O3 catalyst at 233℃ with a space velocity of 1000min-1 . This reaction condition is sufficient to remove the entire CO generated by a family-sized natural gas water heater.

A study was done to determine if the antioxidants found in peanut hulls could be used\r for lessening the corrosion rate of iron. Peanut hulls were ground then divided into two\r batches, P1 and P2, then oven-dried at temperatures of 50°C and 60°C, respectively. The\r moisture content of each batch was then determined before performing methanolic extraction\r to isolate the antioxidants. Eighteen iron strips of approximately the same surface areas were\r thoroughly cleaned and weighed, then divided into six groups. The iron strips in the first five\r groups were respectively coated with pure extract from batch P1; a 1:1 mixture of P1 extract\r and turpentine; pure P2 extract; a 1:1 mixture of P2 extract and turpentine; and pure\r turpentine. No treatment was done on the sixth group. All iron strips were exposed to air to\r allow formation of rust thru atmospheric corrosion. After 12 days, the iron strip were cleaned\r and weighed; then the individual corrosion rates of the metals were determined.\r The corrosion rates of the metals treated with pure P1 extract, the P1-Turpentine, and\r the P2-Turpentine mixtures were found to be significantly lower than the corrosion rates of\r the metals without treatment, at 5% level of significance in a t-Test for independent samples.\r The average corrosion rates of all the treated metals were found to be lower than that of\r metals treated with pure turpentine, though not significantly. The corrosion rate of the metals\r coated with turpentine was not significantly less than that of untreated metals. The corrosion\r rates of the metals were also found not to be dependent with the moisture as there was no\r significant difference in the mean corrosion rates of metals treated with P1 extract and those\r treated with P2 extract, with or without turpentine.\r The project has shown that peanut hull extracts can be used to lessen the production\r of rust on the surface of the metal. Moisture content of the hulls was not found to be a factor\r in lessening the corrosion rate.