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991.
Chu-En Chou Yi-An Chen Yi-Ching Lin Shih-Chieh Kao Chieh-Yu Chang Yen-Ku Wu 《中国化学会会志》2020,67(12):2198-2203
Described is a formal synthesis of racemic schulzeines B and C that intercepts intermediates developed by Gurjar and co-workers. The synthetic sequence features an annulative coupling of a ketimine and acrylic acid enabling the construction of the benzoquinolizidine nucleus in a highly convergent manner. We also examined a continuous-flow version of the thermal aza-annulation, which proved less practical as compared to the batch processes. 相似文献
992.
993.
During the course of investigating the anticancer activities of new compounds, we have synthesized a series of novel cyclic N-hydroxyurea derivatives and several carbamate intermediates1–3. Infrared absorption, nuclear magnetic resonance, and electronic absorption spectra were examined in order to confirm the identities and to study the molecular structure of these compounds. 相似文献
994.
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997.
Dr. Yuan Jay Chang Po‐Ting Chou Szu‐Yu Lin Dr. Motonori Watanabe Zhi‐Qian Liu Ju‐Ling Lin Prof. Dr. Kew‐Yu Chen Prof. Dr. Shih‐Sheng Sun Prof. Dr. Ching‐Yang Liu Prof. Dr. Tahsin J. Chow 《化学:亚洲杂志》2012,7(3):572-581
A series of organic dyes were prepared that displayed remarkable solar‐to‐energy conversion efficiencies in dye‐sensitized solar cells (DSSCs). These dyes are composed of a 4‐tert‐butylphenylamine donor group (D), a cyanoacrylic‐acid acceptor group (A), and a phenylene‐thiophene‐phenylene (PSP) spacer group, forming a D‐π‐A system. A dye containing a bulky tert‐butylphenylene‐substituted carbazole (CB) donor group showed the highest performance, with an overall conversion efficiency of 6.70 %. The performance of the device was correlated to the structural features of the donor groups; that is, the presence of a tert‐butyl group can not only enhance the electron‐donating ability of the donor, but can also suppress intermolecular aggregation. A typical device made with the CB‐PSP dye afforded a maximum photon‐to‐current conversion efficiency (IPCE) of 80 % in the region 400–480 nm, a short‐circuit photocurrent density Jsc=14.63 mA cm?2, an open‐circuit photovoltage Voc=0.685 V, and a fill factor FF=0.67. When chenodeoxycholic acid (CDCA) was used as a co‐absorbent, the open‐circuit voltage of CB‐PSP was elevated significantly, yet the overall performance decreased by 16–18 %. This result indicated that the presence of 4‐tert‐butylphenyl substituents can effectively inhibit self‐aggregation, even without CDCA. 相似文献
998.
Pei‐Ling Chiang Tzu‐Chi Chou Tzu‐Heng Wu Chang‐Chi Li Dr. Chun‐Da Liao Dr. Jeng‐Yu Lin Ming‐Hsueh Tsai Dr. Chia‐Chang Tsai Chih‐Jung Sun Prof. Dr. Ching‐Ho Wang Prof. Dr. Jim‐Min Fang Prof. Dr. Yit‐Tsong Chen 《化学:亚洲杂志》2012,7(9):2073-2079
We have applied a reusable silicon nanowire field‐effect transistor (SiNW‐FET) as a biosensor to conduct ultrasensitive detection of H5N2 avian influenza virus (AIV) in very dilute solution. The reversible surface functionalization of SiNW‐FET was made possible using a disulfide linker. In the surface functionalization, 3‐mercaptopropyltrimethoxysilane (MPTMS) was first modified on the SiNW‐FET (referred to as MPTMS/SiNW‐FET), with subsequent dithiothreitol washing to reduce any possible disulfide bonding between the thiol groups of MPTMS. Subsequently, receptor molecules could be immobilized on the MPTMS/SiNW‐FET by the formation of a disulfide bond. The success of the reversible surface functionalization was verified with fluorescence examination and electrical measurements. A surface topograph of the SiNW‐FET biosensor modified with a monoclonal antibody against H5N2 virus (referred to as mAbH5/SiNW‐FET) after detecting approximately 10?17 M H5N2 AIVs was scanned by atomic force microscopy to demonstrate that the SiNW‐FET is capable of detecting very few H5N2 AIV particles. 相似文献
999.
Shang-Hui Yang Jian-Shian Lin Fuh-Shyang Juang Ding-Chin Chou Ming-Hua Chung Chen-Ming Chen Lung-Chang Liu 《Current Applied Physics》2013,13(5):931-934
In this paper, white light emitting diodes (LEDs) with good color rendering indices (CRI) and high luminous efficiencies have been fabricated by the encapsulation of mixed and double-deck phosphors. Experimental results revealed that white LEDs with the encapsulation of double-deck phosphors exhibited better CRI and higher luminous efficiencies than those with the encapsulation of mixed phosphors because no secondary excitation took place. The hue, CRI, and luminous efficiencies of white LEDs with double-deck phosphors under 200 mA were CIEx,y = (0.357, 0.348), 90, and 62.3 lm/W, respectively while the hue, CRI, and luminous efficiencies of white LEDs with mixed phosphors under 200 mA were CIEx,y = (0.366, 0.354), 89, and 56.5 lm/W, respectively. 相似文献
1000.
Ming-Chu Chou 《代数通讯》2013,41(2):898-911
Let R be a prime ring, L a noncentral Lie ideal of R, and a ∈ R. Set [x, y]1 = [x, y] = xy ? yx for x, y ∈ R and inductively [x, y]k = [[x, y]k?1, y] for k > 1. Suppose that δ is a nonzero σ-derivation of R such that a[δ(x), x]k = 0 for all x ∈ L, where σ is an automorphism of R and k is a fixed positive integer. Then a = 0 except when char R = 2 and R ? M2(F), the 2 × 2 matrix ring over a field F. 相似文献