全國中小學科展

化學

Development of a nano-filtration membrane using different linear aliphatic amines and linear cross-linkers for purification of expensive and precious organic solvents

Theseparation, purification, and recovery of precious organic solvents is a huge challenge for many industriesincludingpetroleumandpharmaceuticalcompanies,sincethesecompaniesusehugequantities of organic solvents [1-2]. Natural dissolvable nanofiltration(ON)has atremendous potential for supplantingafewenergy-concentratedcrudepurgingtechniques,similartorefiningandextraction[3-4- 5]. The importance of OSN is obvious from the fact that one cubic meter of methanol requires 1750 MJ of energy for distillation since the process of distillation is comprised of heating, evaporation, and condensation while OSN can purify the same volume of methanol by consuming 3 MJ of energy [6-7]. Additionally, OSN is a useful technology since it is simpler to use than conventional purification and separationmethods.Themembrane'sporestructure,whichinfluencesbothitsselectivityandpermeance, hasasignificantimpactonhowwellthemembranesperform[8-9].Ingeneral,thetrade-offbetweenflux andselectivityaffectsthemembrane'sperformance.Asaresult,themembranes'fluxandpermeabilityare affectedbythetailoringandtuningoftheirporestructure.Therefore,designinganefficientnanofiltration membranes with ideal porosity is highly desirable. Interfacial polymerization (IP) is highly versatile as it provides a freedom of selection of various monomersfortargetingaspecificapplicationsuchasnanofiltrationandreverseosmosisThepotentialfor organicsolventnanofiltration(ON)toreplacevariousenergy-intensivetraditionalpurificationtechniques, suchasdistillationandextraction,isenormous.[8-9].Despitethefactthatmanydifferentmonomershave been successfully used by utilizing IP to create thin film composite nanofiltration TFC-NF membranes, one of the main limitations of such membranes continues to be the poor selection of closely related comparable nanometer sized solutes. Many efforts are still being made to develop potential monomers with the perfect properties for creating membranes that operate excellently [10-11]. Another strategy is also getting more popular in which different porous additives are added to the TFC membrane either at thesupportleveloractivelayerlevel.Theseadditivesincludecarbonorganicframeworks(COFs),metal organic frameworks (MOFs), hyper-cross-linked porous polymers (HCPs), and natural polymers such as chitosan[12-13-14-15]. However,maintainingthecrystallinity ofsuch additives,particularlyMOFsthat lead to crystalline membranes, is extremely difficult while other additions suffer from aggregation and agglomeration that results in membrane flaws that impair the performance of the membranes [16]. Therefore,changingthechemistryofthereacting monomerduringIPcansignificantlyalterthestructure of the resultant active layers of the membranes. The current study was carried out by using linear aliphatic amines 4A-3P and 4A on a crosslinked PAN support. The study was carried out through interfacial polymerization between either 4A-3P and TPC or 4A and TPC on crosslinked PAN. In comparison to the previous studies where cyclic amines such as piperazine or aromatic amines such as meta-phenylenediamine (MPD) are used, we have used linear aliphatic amines 4A and 4A-3P crosslinked with organic phase containing terephthaloyl chloride (TPC) asacross-linker.TheIPreactionwascarriedoutbetweenamineandTPConacrosslinkedPANsupport. The fabricated membrane was extensively characterized by using scanning electron microscope (SEM), ATR-FTIR, water contact angle (WCA), energy dispersive X-ray (EDX) and elemental mapping . The fabricated membrane was used for OSN applications by using dead-end filtration setup.

複合葡萄糖氧化酶的金奈米團簇應用於葡萄糖檢測

本研究使用牛血清白蛋白(BSA)、穀胱甘肽(GSH)、金離子合成金奈米螢光團簇,並修飾上葡萄糖氧化酶(GOx)。此金奈米團簇上的葡萄糖氧化酶與葡萄糖反應,製造出過氧化氫,改變金奈米螢光團簇表面特性使螢光強度減弱,偵測葡萄糖濃度。 本研究探討不同條件金奈米團簇和不同濃度的葡萄糖反應,知道此材料可檢測到最低濃度的葡萄糖,且金奈米團簇在血液中對葡萄糖具有專一性,可穩定進行血糖檢測。另外,與不同濃度的人體血清樣本反應,發現血清濃度越高的螢光訊號下降明顯,因此可知修飾上葡萄糖氧化酶的穀胱甘肽輔助之牛血清白蛋白金奈米團簇(BSA/GSH-Au NCs)可用於人體血糖檢測。本研究開發出靈敏、快速、穩定的葡萄糖檢測材料,並期待未來能運用於實際的人體血糖檢測上。

以磁鄰近誘發非傳統超導

本研究以熱蒸鍍法製作 31 nm Sn 顆粒以及 15% Sn 被 Ni 取代的 38 nm Sn85Ni15 顆粒,探討奈米化及磁鄰近(magnetic proximity)共同引發的非傳統超導行為。分析 X 光繞射譜圖所得電子密度分布,顯示添加 Ni 引發部分內層電子轉移到鍵結區域。磁矩量測顯示 31 nm Sn 在300 K 仍具鐵磁性,而 38 nm Sn85Ni15 的磁矩是 31 nm Sn 的 3 倍之多,指出所添加的 Ni 確實提供較高磁分量,在 Sn 離子鄰近提供一區域磁場,誘發磁鄰近效應。38 nm Sn85Ni15 的超導溫度大幅提升到 7.75 K 為塊材 Sn 超導溫度 3.72K 的 2.1 倍,且外加磁場對弱化超導溫度的效率,在 200 Oe 出現大幅轉折,高於 200 Oe 對超導溫度幾乎沒有影響,出現拒磁及容磁兩種超導行為。這些行為可以用顆粒內層為 s-波(s-wave)超導耦合及外層為非 s 波(non-s-wave) 超導耦合來理解。

探討鐵鎳合金催化劑對電解產氫之影響

目前大部分電解產氫反應(HER)均使用貴金屬,如鉑和鈀,作為催化劑。而我們提出了更便宜的 FexNiyP 金屬磷化物用於經濟製氫。在催化劑的製備中採用不同的化學成分(x/y 比例)和合成條件(氧化溫度)。並將合成樣品通過掃描式電子顯微鏡(SEM)、能量色散 X射線光譜(EDS)和 X光繞射儀(XRD)進行了鑑定,以確認其形態、成分和晶體結構。再通過線性掃描伏安法(LSV)測試了它們的 HER催化效率。實驗結果發現,磷化程度強烈影響催化性能,且可以通過合成條件來適當調整,而 250° C是最佳氧化溫度。此外,電化學測試顯示,FeP 啟動反應所需之能量最低,具有最低的過電位(overpotential);而 NiP 反應路徑最佳,具有最低的塔菲爾斜率(Tafel slope)。我們的結果解決了 HER的反應機構,並對氫燃料生產的發展提供了有用信息。

芋頭生物塑膠材質的熱水即溶包研製

2023年聯合國氣候變遷大會(COP28)決議 2050年淘汰化石燃料。2022年聯合國環境大會制定從源頭減少塑膠垃圾的公約。為了回應這些全球目標,本研究利用廢棄芋頭皮的黏性製作生物塑膠,用於泡麵內調味料的熱水即溶包。常溫下為調味料包裝袋,熱水沖泡後即可溶解,成為富含營養的食材。 我們發現有八種配方能夠成功使其成形。其中,成本最低的配方為芋頭:明膠:小燭樹蠟:甘油:水=20:15:9:9:70。該產品在76°C以上的熱水中能夠溶解,第一次裂解時間為8秒鐘以內,之後會完全溶解。該裂解時間y(s)與溫度x(°C)的關係為:y=9.53×10¹¹x⁻⁵.⁹⁸。這使其適合用於泡麵時的熱水溫度,約 80°C以上。 物理性質包括:拉伸強度為0.70kgf/15mm,伸長率為20.4%,密度為1.11 g/cm³,含水率為20.3%。所有配方成分皆可食用,並可溶解於熱水中,適合作為泡麵調味料塑膠包的替代品,有助於減少農產廢棄物的處理量。

二氧化鋯量子點在文物修復與減碳科技應用的潛力

本研究成功以水熱法在 110°C 下合成了約3.90 nm 大小的ZrO2量子點(QDs)。此設計的ZrO2 QDs 能隙為5.03 eV(波長λ < 300 nm),在可見光和紫外光範圍內無明顯吸收特徵,呈現高度惰性和穩定性,適合應用於抗紫外線塗層或顏料。而ZrO2 QDs 表面豐富的氧空位與不同溫度下的CO₂轉化率及CO/CH₄產物選擇性相關。氧空位為帶部分正電的酸性活性位,CO2作電子受體為路易士酸。經氧氣環境加熱處理後的ZrO2 QDs 能提高CO2轉化率且在低溫條件下選擇性較高能促進電子轉移生成CH₄(每分子8e⁻ 轉移)。不同金屬簇(如Fe、Ni、Co和Cu)表面修飾後,Fe-ZrO2 QDs 被證明為最佳催化劑,低溫下更有效促進CH₄生成,且優於ZrO2 QDs。這顯示Fe與ZrO2間存在顯著的強金屬-載體相互作用(SMSI),提升Fe捕捉CO₂分子的能力。此特性突顯ZrO2於碳減排技術的潛力,能有效將CO₂轉化為可再利用的碳基燃料或化學原料,為減少溫室氣體提供實用解決方案。

可同時用於霧水收集與風力發電的石墨烯仿生陣列魔毯

受到地區限制,偏遠地區一直面臨著缺水和缺電的問題。有許多解決方案,其中一個被視為在乾燥地區收集水的有效方法是薄膜霧氣收集技術。這項研究受到自然界沙漠甲蟲的啟發。我們在不吸水的石墨烯/PVDF基底上使用仿生的幾丁聚醣陣列,幫助水滴在霧氣中凝結和滾動脫落,使水收集效率達到0.63LMH。此外,我們使用石墨烯和離子液體一起誘導PVDF晶型自組裝成具壓電性的β相,獲得最適化薄膜的電壓輸出可達到13V(±6.5V)。我們還對於薄膜進行同時取水和取電的可行性評估,結果顯示,在4m/s的霧氣風速下,水收集效率為0.74LMH,發電功率為99.2mW/m2。基於上述研究結果,我們證實了使用單一薄膜利用霧和風作為驅動力,可實現同時產生水和電,這對解決偏遠地區的缺水與缺電問題提供了新的解決方案。

含鐵、鎳之過渡金屬錯合物相變材料研究暨應用研析

量子運算發展日新月異,人類對上網溝通保密的需要與日俱增。市場已有量子資訊加解密所需的金鑰分配系統(QKD)搭配機密資料保險庫(Archive)。然實體金鑰因其安全性,不可或缺。本文探討以製備含鐵、鎳過渡金屬錯合物,利用含 X 光繞射儀等設備檢測、分析其結構與相變。並研析將該錯合物作為分子開關裝置,導入半導體製程,應用於研發上述金鑰之可行性。

Observation of volcanic gases with a simple alkaline filter paper method at Sakurajima Volcano in Kagoshima, Japan.

There are many active volcanoes in Kagoshima Prefecture, including Sakurajima Volcano. So, the volcanic disaster prevention is an urgent issue. Also, Hirabayashi of Tokyo Institute of Technology reported that the molar ratio of HCl/SO2 is large during periods of high HCl/SO2 and conversely small during periods of low HCl/SO2 , and that explosions increase one month after the molar ratio of HCl/SO2 increases during periods of no explosions. We decided to determine the composition ratio of volcanic gases (sulfur dioxide, hydrogen chloride, and hydrogen fluoride) emitted from Sakurajima crater in order to understand and predict volcanic activities. Th us, we established a simple collection method for volcanic gases using alkaline filter paper and a quantitative method using a self m ade absorbance photometer so that even high school students could perform the measurement at many points, and we discussed the data from various perspectives. Furthermore, since last year, we have found a correlation between the variation of Cl-/SO2 ratio and the number of eruptions at Sakurajima volcano. Also, a model for the behavior of volcanic gases was developed based on a comparison of the amount of volcanic ash and the number of eruptions.

自組裝DNA探針於GNP@PANI電極以檢測miRNA

在許多疾病,如癌症、心血管等疾病中,微核醣核酸 ( microRNA,簡稱miRNA) 的表現水平可作為診斷指標。現行檢測miRNA多使用RT-qPCR,然而此技術成本高、操作繁瑣且耗時。本研究自行設計可抓取目標miR-155的DNA分子探針,透過化學合成與修飾將此探針接合在奈米金-聚苯胺( GNP@PANI )電極上,組裝出具靈敏度與特異性的DNA分子電極。實驗結果顯示:此自組裝探針電極具有良好的線性檢量關係,偵測極限可達0.1 nM。在摻雜多種miRNA的樣品中,此電極仍具有極佳的專一性,回收率高達101.5 %。應用於含生物基質的尿液樣本,可不受背景干擾,其檢測差異僅約0.4 %。本研究採用電化學技術來檢測miRNA,不但成本低、操作簡便,且可依據目標分子進行客製化設計,為新一代檢測技術開創前景。