利用奈米級的二氧化鈦〈TiO?〉在紫外光降解幾丁聚醣的研究
本實驗中利用二氧化鈦能在常溫下經紫外線催化,分解空氣中的水分子,產生自由基的特性,攻擊幾丁聚醣中碳與氧鍵結的部分,使chitin 的分子量成功的從近50000 降解至3000以下;並可利用照射時間的不同,降解出分子量不同的chitin。此法不但大大排除利用化學法降解時廢液處理上的問題,而且還能利用照紫外光時間長短的不同來控制分子量的大小;又奈米級二氧化鈦(TiO?)在紫外光在短短四個小時之內就有很好的降解效果,除了節省了反應所需的時間外,降解前後幾丁聚醣的濃度也很高,因此所需的成本也遠低於當今利用酵素降解的方法。In the experiment, we used the properties of TiO? that can be catalyzed by UV rays and breaking the molecules of H?O and produce free radicals, which free radicals can attack the chemical bond between carbon and oxygen in chitin, successfully degrading chitin's molecular weight from 50000 to 3000.We also use different shining times to degrade chitosan into different molecular weight. In this way, we not only readily solve the problem of treating waste liquids produced by chemical degradation, but also control the molecular weight by different UV ray shining time. For another thing, TiO? in the nanometer level has excellent effect on degradation within 4 hours under UV ray shining. It not only cut back the reaction time but also produced high concentration of the chitin after degradation. As a result, the cost is much lower than that of using enzyme to degrade chitin.
醇類凝膠的安定與老化及其結晶情形
在這篇報告中,特別針對了凝膠的機制去做探討,以許多的實驗數據,再輔以凝膠的基本定義,去臆測各種有關於凝膠的老化機制,並藉由其過程中推斷出一些有趣的性質: 1. 當膠體內水分含量不同,與凝結後的醇類膠體有相當的影響。 2. 凝膠老化後形成的結晶形狀,因凝膠溶質、溶液內互溶性的不同,形成了不同凝聚程度的絮聚現象。 3. 同種陰陽離子在不同碳數的醇類凝膠中,因為與水溶液的互溶性也有所不同,間接影響了凝膠的形成速度,這對於安定來說,包含了很大的意義存在。 4. 對於其老化的速度,會因其安定程度而有所影響。 5. 老化後的溶液內的陰陽離子濃度,會直接影響其再次安定與老化的情形。 In this report, we especially do the discussion to the mechanism of the gel. With a lot of experimental data and the basic definition of gel, we conjecture various kinds of aging mechanism about the gel, and infer some interesting problems from its course: 1. Moisture content in the gel effect the gel’s quality after alcohol condensed greatly. 2. Because of dissolving difference between the alcohol and the other substances, crystallization forms after the gel aged have formed different degrees phenomenon of gathered. 3. The same kind of negative and positive ion among the alcohol gel that have different carbon atoms. Because of dissolving difference between the ions and the solution, the ions influence forming speed of gel indirectly. To being stable of the gel, this phenomenon includes very great meaning. 4. Stable degree of the gel can influence its speed of aging. 5. The consistency of negative and positive ion in the aging solution of the gel can influence its stable and aging situation again directly.
修正駕駛汽車習慣之省油案
修正汽車駕駛喜歡猛踩加油踏板之習慣,把一加油動作分解成多段階級式加油動作,使自動變速箱內扭力降低達到順利變換高速檔o 達到節約能源.減少污染.提高效率之目的。The oil-saving project by adjusting the driving habits To avoid the habit of easily step the pedal to speed up, we divide it into multi-step fuel-filling procedures. Therefore, they decrease the wristing strength of transistor inside auto speed-changing box and reach high-speed brake smoothly. As a result, it can save energy, reduce pollution and increase high efficiency.
鈦鈦相傳-以新穎水熱-化學電池法製備二氧化鈦
In our experiment, the novel hydrothermal-galvanic couple method is used to produce nanostructured TiO2 thin film. Compared with the traditional hydrothermal method, whose process is conducted under high temperature and high pressure, the hydrothermal-galvanic couple method is a thermally and electrochemically driven process. The titanium atom is gradually oxidized on the surface driven by potential difference, and eventually become nanostructured TiO2. The advantages of the hydrothermal-galvanic couple method are numerous: they are simple, environment-friendly and energy-saving. Experimental parameters include time, concentration and types of solution. The hydrothermal method is used for comparison. By the cross-section and surface pictures of Field-emission scanning electron microscopy (FE-SEM), we can clearly observe that there is obvious change on the titanium surface, along with increased thickness and altered surface structure. The film of hydrothermal-galvanic couple method is thicker than that of hydrothermal method. Thickness increases with time and concentration as well. Both the hydrophile and decomposition of methylene blue examination indicate that the product on the surface contains photocatalyst-like feature.我們利用新穎水熱-化學電池法製備奈米級二氧化鈦薄膜。相較於一般傳統水熱法高溫高壓的製程,水熱-化學電池法結合了熱能與化學電能,讓鈦原子在電位差的驅動下於表面逐步氧化,最終形成奈米級二氧化鈦粒子,具備簡易、環保、省能的優點。實驗參數包括時間、濃度、溶液種類,並以水熱法作為對照組。由FE-SEM 橫截面圖及表面圖可清楚看到鈦的表面有明顯變化,膜厚增加、表面結構改變;以水熱-化學電池法所得的薄膜明顯較水熱法厚,而其厚度隨著濃度及時間的增加也有增加的趨勢,由試片親水性測試與亞甲基藍吸光度測試,皆顯示試片的表面產物具有類似光觸媒的性質。
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
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。