2016 International Conference on Networking and Network Applications (NaNA), 2016
This paper proposes a method to detect the region of intangible events such as toxic gases leakin... more This paper proposes a method to detect the region of intangible events such as toxic gases leaking or radiations. The proposed method will randomly place a group of agents within the disaster area. Those placed agents can spread themselves over the disaster area to detect the intangible events. Instead of placing all agents into the disaster area at a time, agents are placed incrementally. The simulation results show the proposed method can use fewer agents to figure out the intangible event area than the common method, which all agents are placed in advance. The size of the uncovered intangible event region of the proposed method is less than 1%. The size of the false positive area is also reduced.
本文的研究目的是設計並合成具有推電子基-架橋-拉電子基的分子系統,並分為三個部分探討熱致變色現象、價態間電荷轉移機制以及作為分子開關之研究。在第一部分的研究是發展具有可逆性之熱致變色分子,如圖(... more 本文的研究目的是設計並合成具有推電子基-架橋-拉電子基的分子系統,並分為三個部分探討熱致變色現象、價態間電荷轉移機制以及作為分子開關之研究。在第一部分的研究是發展具有可逆性之熱致變色分子,如圖(1)所示,藉由改變不同的共軛架橋官能基,探討化合物在質子化後的熱致變色行為。由吸收光譜和螢光光譜的結果顯示,質子化後產生紅位移現象,並且螢光產生了驟息現象。在乙腈溶液中可藉由升溫回復至中性狀態,而在二氯甲烷溶液中,則是需要降低溫度使其回復至中性狀態。氫核磁共振光譜得知,質子化的位置在苯並噻唑的氮原子上,並由變溫實驗可得知氫訊號可隨溫度升高而回復至原本的中性狀態。當架橋分子的芳香性越差,中性狀態和質子化狀態之間的反應焓差異也較小,因此具有較佳之熱致變色特性,並且擁有較好的可逆性。 第二部分的研究是以銅二價金屬離子作為氧化劑將苯胺衍生物氧化形成自由基陽離子,如圖2所示,以芴作為連接苯胺基的架橋分子發現到當其中一個苯胺被氧化形成自由基陽離子時,會產生價態間電荷轉移的現象,因此在吸收光譜中會在近紅外光區有吸收峰的生成。由電子自旋共振光譜實驗得知,自由基陽離子的形成可藉由量測未成對電子訊號證明其存在。除了芴之外,引入不同的架橋分子對於電荷轉移現象也有明顯的影響。 具有光致變色特性的二噻吩乙烯除了可經由照光進行結構之間的轉換,氧化還原的方式也可達到同樣的目的,原因在於經由所產生自由基陽離子可驅使開環或合環反應的進行。在本文的研究中在二噻吩乙烯引入二甲苯胺基並修飾不同的推拉電子基集團,如圖3所示,以銅二價金屬離子作為氧化劑可將苯胺進行氧化形成自由基陽離子,在合環狀態在形成自由基陽離子後可進一步做開環反應形成開環狀態的自由基陽離子。除此之外,由光譜電化學實驗可得到同樣的實驗結果,並藉由還原電位回到原本的中性狀態,電子自旋共振光譜說明開環反應的過程中有自由基陽離子的生成。The research is focused on the design and synthesis of donor-bridge-acceptor systems in the application of thermochromism, intervalence charge transfer, and molecular switches. In the first part of the study is t...
We report here, for the first time, the experimental observation on the excited-state intramolecu... more We report here, for the first time, the experimental observation on the excited-state intramolecular proton transfer (ESIPT) reaction of the thiol proton in room-temperature solution. This phenomenon is demonstrated by a derivative of 3-thiolflavone (3TF), namely, 2-(4-(diethylamino)phenyl)-3-mercapto-4H-chromen-4-one (3NTF), which possesses an -S-H···O═ intramolecular H-bond (denoted by the dashed line) and has an S1 absorption at 383 nm. Upon photoexcitation, 3NTF exhibits a distinctly red emission maximized at 710 nm in cyclohexane with an anomalously large Stokes shift of 12 230 cm-1. Upon methylation on the thiol group, 3MeNTF, lacking the thiol proton, exhibits a normal Stokes-shifted emission at 472 nm. These, in combination with the computational approaches, lead to the conclusion of thiol-type ESIPT unambiguously. Further time-resolved study renders an unresolvable (<180 fs) ESIPT rate for 3NTF, followed by a tautomer emission lifetime of 120 ps. In sharp contrast to 3NTF, both 3TF and 3-mercapto-2-(4-(trifluoromethyl)phenyl)-4H-chromen-4-one (3FTF) are non-emissive. Detailed computational approaches indicate that all studied thiols undergo thermally favorable ESIPT. However, once forming the proton-transferred tautomer, the lone-pair electrons on the sulfur atom brings non-negligible nπ* contribution to the S1' state (prime indicates the proton-transferred tautomer), for which the relaxation is dominated by the non-radiative deactivation. For 3NTF, the extension of π-electron delocalization by the diethylamino electron-donating group endows the S1' state primarily in the ππ* configuration, exhibiting the prominent tautomer emission. The results open a new chapter in the field of ESIPT, covering the non-canonical sulfur intramolecular H-bond and its associated ESIPT at ambient temperature.
2016 International Conference on Networking and Network Applications (NaNA), 2016
This paper proposes a method to detect the region of intangible events such as toxic gases leakin... more This paper proposes a method to detect the region of intangible events such as toxic gases leaking or radiations. The proposed method will randomly place a group of agents within the disaster area. Those placed agents can spread themselves over the disaster area to detect the intangible events. Instead of placing all agents into the disaster area at a time, agents are placed incrementally. The simulation results show the proposed method can use fewer agents to figure out the intangible event area than the common method, which all agents are placed in advance. The size of the uncovered intangible event region of the proposed method is less than 1%. The size of the false positive area is also reduced.
本文的研究目的是設計並合成具有推電子基-架橋-拉電子基的分子系統,並分為三個部分探討熱致變色現象、價態間電荷轉移機制以及作為分子開關之研究。在第一部分的研究是發展具有可逆性之熱致變色分子,如圖(... more 本文的研究目的是設計並合成具有推電子基-架橋-拉電子基的分子系統,並分為三個部分探討熱致變色現象、價態間電荷轉移機制以及作為分子開關之研究。在第一部分的研究是發展具有可逆性之熱致變色分子,如圖(1)所示,藉由改變不同的共軛架橋官能基,探討化合物在質子化後的熱致變色行為。由吸收光譜和螢光光譜的結果顯示,質子化後產生紅位移現象,並且螢光產生了驟息現象。在乙腈溶液中可藉由升溫回復至中性狀態,而在二氯甲烷溶液中,則是需要降低溫度使其回復至中性狀態。氫核磁共振光譜得知,質子化的位置在苯並噻唑的氮原子上,並由變溫實驗可得知氫訊號可隨溫度升高而回復至原本的中性狀態。當架橋分子的芳香性越差,中性狀態和質子化狀態之間的反應焓差異也較小,因此具有較佳之熱致變色特性,並且擁有較好的可逆性。 第二部分的研究是以銅二價金屬離子作為氧化劑將苯胺衍生物氧化形成自由基陽離子,如圖2所示,以芴作為連接苯胺基的架橋分子發現到當其中一個苯胺被氧化形成自由基陽離子時,會產生價態間電荷轉移的現象,因此在吸收光譜中會在近紅外光區有吸收峰的生成。由電子自旋共振光譜實驗得知,自由基陽離子的形成可藉由量測未成對電子訊號證明其存在。除了芴之外,引入不同的架橋分子對於電荷轉移現象也有明顯的影響。 具有光致變色特性的二噻吩乙烯除了可經由照光進行結構之間的轉換,氧化還原的方式也可達到同樣的目的,原因在於經由所產生自由基陽離子可驅使開環或合環反應的進行。在本文的研究中在二噻吩乙烯引入二甲苯胺基並修飾不同的推拉電子基集團,如圖3所示,以銅二價金屬離子作為氧化劑可將苯胺進行氧化形成自由基陽離子,在合環狀態在形成自由基陽離子後可進一步做開環反應形成開環狀態的自由基陽離子。除此之外,由光譜電化學實驗可得到同樣的實驗結果,並藉由還原電位回到原本的中性狀態,電子自旋共振光譜說明開環反應的過程中有自由基陽離子的生成。The research is focused on the design and synthesis of donor-bridge-acceptor systems in the application of thermochromism, intervalence charge transfer, and molecular switches. In the first part of the study is t...
We report here, for the first time, the experimental observation on the excited-state intramolecu... more We report here, for the first time, the experimental observation on the excited-state intramolecular proton transfer (ESIPT) reaction of the thiol proton in room-temperature solution. This phenomenon is demonstrated by a derivative of 3-thiolflavone (3TF), namely, 2-(4-(diethylamino)phenyl)-3-mercapto-4H-chromen-4-one (3NTF), which possesses an -S-H···O═ intramolecular H-bond (denoted by the dashed line) and has an S1 absorption at 383 nm. Upon photoexcitation, 3NTF exhibits a distinctly red emission maximized at 710 nm in cyclohexane with an anomalously large Stokes shift of 12 230 cm-1. Upon methylation on the thiol group, 3MeNTF, lacking the thiol proton, exhibits a normal Stokes-shifted emission at 472 nm. These, in combination with the computational approaches, lead to the conclusion of thiol-type ESIPT unambiguously. Further time-resolved study renders an unresolvable (<180 fs) ESIPT rate for 3NTF, followed by a tautomer emission lifetime of 120 ps. In sharp contrast to 3NTF, both 3TF and 3-mercapto-2-(4-(trifluoromethyl)phenyl)-4H-chromen-4-one (3FTF) are non-emissive. Detailed computational approaches indicate that all studied thiols undergo thermally favorable ESIPT. However, once forming the proton-transferred tautomer, the lone-pair electrons on the sulfur atom brings non-negligible nπ* contribution to the S1' state (prime indicates the proton-transferred tautomer), for which the relaxation is dominated by the non-radiative deactivation. For 3NTF, the extension of π-electron delocalization by the diethylamino electron-donating group endows the S1' state primarily in the ππ* configuration, exhibiting the prominent tautomer emission. The results open a new chapter in the field of ESIPT, covering the non-canonical sulfur intramolecular H-bond and its associated ESIPT at ambient temperature.
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