Modified structure of two-dimensional polythiophene derivatives by incorporating electron-deficient units into terthiophene-vinylene conjugated side chains and the polymer backbone: synthesis, optoelectronic and self-assembly properties, and photovoltaic application

Molecular engineering on the conjugated side chains of two-dimensional (2D) conjugated polymers was conducted and its effect on the optical, electronic, self-assembly and photovoltaic properties was investigated. A new monomer, M2, was prepared by capping (E)-3′-(2-(2,5-dibromothiophen-3-yl)vinyl)-4,4′′-bis(2-ethylhexyl)-2,2′:5′,2′′-terthiophene, M1, with two heptanoyl groups, and then coupled with 5,5′-bis(trimethylstannyl)-2,2′-bithiophene via microwave-assisted Stille polymerization to produce a series of polythiophene derivatives with terthiophene-vinylene conjugated side chains, TTV–PTs. Copolymer P2 shows a down-shifted HOMO energy level, enhanced solubility, and red-shifted absorption, as compared with P1; however, the bulky side chains significantly disrupt the coplanarity of thiophene rings in the polymer backbone and the ability to self-assemble into an ordered structure. The GIXRD measurements reveal that the original crystallinity of P1 can be recovered by simply inserting a few 2,1,3-benzothiadiazole units into the polythiophene main chain in P2 through a random copolymerization route to yield a terpolymer, P3, which possesses excellent crystallinity, thereby causing a three-fold increment in hole mobility. Furthermore, the P1/PC_(61)BM, P2/PC_(61)BM, and P3/PC61BM solar devices exhibit power conversion efficiencies of 3.89%, 1.52%, and 4.17%, respectively, under AM1.5G illumination with an intensity of 100 mW cm^(−2)

Synthesis and Characterization of Two-Dimensional Conjugated Polymers Incorporating Electron-Deficient Moieties for Application in Organic Photovoltaics

A series of novel p-type conjugated copolymers, PTTVBDT, PTTVBDT-TPD, and PTTVBDT-DPP, cooperating benzo[1,2-b:4,5-b′]dithiophene (BDT) and terthiophene-vinylene (TTV) units with/without thieno[3,4-c]pyrrole-4,6-dione (TPD) or pyrrolo[3,4-c]pyrrole-1,4-dione (DPP) via Stille polymerization were synthesized and characterized. Copolymer PTTVBDT shows a low-lying HOMO energy level and ordered molecular-packing behavior. Furthermore, two terpolymers, PTTVBDT-TPD and PTTVBDT-DPP, display stronger absorption ability, alower-lying HOMO energy level, and preferred molecular orientation, due to the replacement TTV-monomer units with electron-deficient groups. Furthermore, bulk-heterojunction organic solar cells were fabricated using blends of the PTTVBDT-TPD, and PC_(61)BM gave the best power conversion efficiency of 5.01% under the illumination of AM 1.5G, 100 mW·cm^(−2); the short circuit current (J_(sc)) was 11.65 mA·cm^(−2) which displayed a 43.8% improvement in comparison with the PTTVBDT/PC_(61)BM device. These results demonstrate a valid strategy combining the two-dimensional molecular structure with random copolymerization strikes promising conjugated polymers to achieve highly efficient organic photovoltaics

Isolation, Purification and Serological Studies of Bitter Gourd Woodiness Disease

苦瓜組織硬化果實，外觀凸粒略有壞疽，果肉內層呈木栓化，烹調後不易 熟透軟化，失去食用價值，但植株葉片並無嵌紋病徵。 為探討造成果實 木栓硬化原因，首先將硬果以 10倍量 0.1 M 磷酸緩衝液 pH 7.2 研磨， 粗汁液接種至供試植物，經觀察後並無病徵表現。改以低高速交替離心分 離純化後再分離，得到分離株 A、分離株 B，兩種不同性質的分離株純化 試料利用電子顯微鏡觀察， 在分離株 A 觀察到平均長約 750 nm、寬 12 nm 之長絲狀病毒粒子，超薄切片中，在奎藜細胞質內可清楚看到風車狀 (pinwheel) 與漩渦狀( scroll) 的內含體存在，其鞘蛋白分子量約為 34.4 kDa， 在血清雙向擴散反應中，與ZYMV、 MVbMV、 PRV-W 皆有沉 澱帶反應， 由形態大小及內含體種類判定長絲狀病毒屬potyvirus 群； 又分離株 B 則觀察到直徑 30 nm，中心有明顯核心 (core) 之球形病毒 粒子， 鞘蛋白分子量約為 25.7 kDa，從寄主範圍、理化性質、病毒粒子 形態與大小鞘蛋白分子量以及血清雙擴散反應和 CMV 有沉澱帶產生， 而知分離株病毒 B 應為 tomatoaspermy virus，屬 cucumovirus 群中 之一員。將長絲狀、球形病毒純化後，分別免疫注射至紐西蘭白兔製備抗 血清， 取球形病毒抗血清以 12 ％硫酸鈉鹽析法純化抗體 IgG 供酵素連 結抗體試驗， 即將鹼性磷酸酵素 (AP) 與山葵過氧化酵素 (HRP)， 嚐試 在酸性域(pH 5.8) 和微鹼性域 (pH 7.8) 下透析再和抗體連結，然後以 Sepharose CL-6B 管柱分離，結果 AP、HRP 主要的酵素連結抗體皆落在 pH 7.8 的第一吸收峰試料內。 同時以相同方法所得之酵素連結，但最後 不經管柱分離而改以原緩衝液透析處理，比較以管柱分離及透析處理的酵 素連結抗體在偵測靈敏度上之差異。 結果發現在抗體 IgG 0.5 ug/ml 時 ， 管柱分離的 AP、HRP 的連結抗體可稀釋 8,000 倍、16,000 倍，而透 析處理的 AP 可以稀釋至 16,000 倍，HRP 則可稀釋至 64,000 倍； 當 抗體 IgG 濃度為 0.05 ug/ml 時，僅透析處理的 HRP 稀釋至 16,000 倍 時尚有肉眼可辨別的明顯呈色反應。 在被體檢粗汁液 10 倍系列稀釋偵 測中， 當抗體 IgG 0.5 ug/ml、酵素連結抗體稀釋 4,000 倍時，管柱分 離的 AP 與 HRP 連結抗體，以肉眼分辨呈色反應可至粗汁液的 10-3 倍 。 若抗體IgG 濃度在 0.5 ug/ml、而酵素連結抗體稀釋 16,000 倍，則 透析處理的 AP 連結抗體只能到 10- 2， 而 HRP 則在粗汁液 10-3 仍 有明顯呈色反應。 抗體 IgG 濃度降到 0.05ug/ml、酵素連結抗體稀釋同 樣在 16,000 倍時，透析處理的 AP 連結抗體， 僅能偵測到粗汁液的 10-1 有微弱呈色反應，而 HRP 仍可以肉眼觀察偵測到粗汁液 10-3 倍， 由此而知 HRP 連結抗體的粗汁液偵測靈敏度為 AP 連結抗體的 100 倍。Necrotic lesions appeared on fruits of bitter gourd plants which beared normallooking leaves. Association of woodiness symptoms were also observed on fruitswith necrosis. Inoculation with crude extracts from symptomatic tissues ofdiseased fruits failed to produce symptoms on indicator plants. Differentialcentrifugation followed by gel filtration of tissue extracts of diseasedfruits resulted in two preparations: preparation A and preparation B. Bothpreparations were infectious, however. Electron microscopic examination ofpreparation A revealed the presence of filamentous particles measured 750 by12 nm. Preparation B, when examined under the electron microscope, showed thepresence of spherical particles about 30nm in diameter. The filamentous virushad a thermal-inactivation temperature between 50* and 60 ℃, a dilutionendpoint of 10-5. It retained infectivity for about 15 to 20 days at 4 ℃. At20 ℃ the virus lost infectivities in three days. Ultra-thin sections showedthe presence of pinwheel and scroll structures in the cytoplasmic inclusionsof infected C. quinoa. Polyacrylamide electrophoresis of the SDS- dissociatedviral preparation showed the presence of a protein band with estimatedrelative molecular mass of 34.3 kDa. In agar gel double diffusion tests thevirus reacted with zucchini yellow mosaic viurs, melon vein- banding mosaicviurs and papaya ringspot virus type W. The virus was tentatively classifiedas a member of potyvirus. The 30 nm spherical virus had a thermal-inactivationpoint between 70*and 80 ℃ and a dilution endpoint of 10-5 to 10-6. Itretained infectivty for more than 30 days at 4 ℃. Purified virus particlescontained one protein with estimated relative molecular mass about 25.7 kDa.The virus reacted with the antiserum prepared to cucumber mosic virus in agargel double diffusion tests, produced in rabbits individually against bothpotyvirus and cucumovirus. and was tentatively identified as tomato aspermycucumovirus. Antisera were Antibodies were purified by precipitation in 12 ％sodium sulfate. Alkiline phosphatase (AP) and horseradish peroxidase (HRP)were used to prepare enzyme-antibody conjugates. The step procedure followed bydialysis were utilized in preparing the conjugates. The conjugates werefurther purified by column chromatography on Sepharose CL-6B gel. Tests of theconjugates showed that losses of enzyme activities after Sepharose CL-6Bchromatography. At 0.5 ug/ml coating antibody concentration, AP- conjugateretained 1/2 of enzyme activity after chromatograph; Where as HRP-conjugateretained 1/4 of its activity. At 0.05 ug/ml coating antibody concentration,only the HRP-conjugate could be used at a dilution of 1/16,000. BothAP-antibody and HRP-antibody conjugates were used to determine the viraltiters in infected Nicotiana tabacum L. cv.T5 plant. The dilution endpoitns ofviral titers were 10-3 when both AP and HRP-conjugates were used at 1 to 4,000dilutions. At 1 to 16,000 conjugate dilutions, viral titers were 10-2and 10-3when AP- conjugate and HRP-conjugate were used, respectively. At 0.05 ug/mlcoating antiobody concentration, the viral titer was 10-1 by AP-conjugate an10-3 by HRP-conjugate when both conjugates were used at to 16,000 dilutions

Novel Two-Dimensional Conjugated Polymer Containing Fluorinated Bithiophene as Donor and Benzoselenodiazole as Acceptor Units with Vinyl-Terthiophene Pendants for Polymer Photovoltaic Cells

Novel two-dimensional conjugated copolymer, abbreviated as PDTBSeVTT-2TF, containing electron-deficient 4,7-di(thiophen-2-yl)benzo[c][1,2,5]selenodiazole (DTBSe) unit, conjugated vinyl-terthiophene (VTT) side chain and 3,3′-difluoro-2,2′-bithiophene (2TF) was designed and synthesized using microwave-assisted Stille cross-coupling polymerization. UV–visible absorption and cyclic voltammetry studies revealed that this copolymer possesses a strong and broad absorption in the range of 300–800 nm and a narrow optical bandgap (Eg) of 1.57 eV with low-lying HOMO and LUMO energy levels. Further, the bulk heterojunction polymer solar cells (PSCs) were fabricated using PDTBSeVTT-2TF as donor and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) as acceptor with an inverted device structure of ITO/ZnO/PDTBSeVTT-2TF:PC71BM/V2O5/Ag. The processing temperature of blend solution for preparing PDTBSeVTT-2TF:PC71BM active layer showed obvious impact on the photovoltaic performance of solar devices. The cell fabricated from the blend solution at 65 °C exhibited enhanced power conversion efficiencies (PCE) of 5.11% with a Jsc of 10.99 mA/cm−2 compared with the one at 50 °C, which had a PCE of 4.69% with a Jsc of 10.10 mA/cm−2. This enhancement is due to the dissolution of PDTBSeVTT-2TF clusters into single molecules and small aggregates, improving the miscibility between the polymer and PC71BM and thus increasing the donor/acceptor interface

高中職學生電腦經驗、資訊素養與電腦態度之相關研究

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