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排序方式: 共有361条查询结果,搜索用时 31 毫秒
61.
Qi Xiao Jingjing Tian Qifan Xue Jing Wang Bijin Xiong Mengmeng Han Zhen Li Zonglong Zhu Hin‐Lap Yip Zhong'an Li 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(49):17888-17894
Development of high‐performance dopant‐free hole‐transporting materials (HTMs) with comprehensive passivation effects is highly desirable for all‐inorganic perovskite solar cells (PVSCs). Squaraines (SQs) could be a candidate for dopant‐free HTMs as they are natural passivators for perovskites. One major limitation of SQs is their relatively low hole mobility. Herein we demonstrate that polymerizing SQs into pseudo two dimensional (2D) p–π conjugated polymers could overcome this problem. By rationally using N,N‐diarylanilinosquaraines as the comonomers, the resulting polysquaraine HTMs not only exhibit suitable energy levels and efficient passivation effects, but also achieve very high hole mobility close to 0.01 cm?2 V?1 s?1. Thus as dopant‐free HTMs for α‐CsPbI2Br‐based all‐inorganic PVSCs, the best PCE reached is 15.5 %, outperforming those of the doped‐Spiro‐OMeTAD (14.4 %) based control devices and among the best for all‐inorganic PVSCs. 相似文献
62.
Dong Sheng Zhang Kai Liu Xiang Yin Qingwu Yip Hin-Lap Huang Fei Cao Yong 《中国科学:化学(英文版)》2019,62(1):67-73
An organic-inorganic hybrid cathode interfacial layer(CIL) was developed by doping ZnO with the naphthalene-diimide based derivative NDI-PFNBr. It was found the resulting organic-inorganic hybrid CIL showed apparently improved conductivity and could act as an effective cathode interlayer to modify indium tin oxide(ITO) transparent electrodes. As a result, by employing the blend of PTB7-Th:PC71BM as the photoactive layer, the inverted polymer solar cells(PSCs) exhibited a remarkable enhancement of power conversion efficiency(PCE) from 8.52% for the control device to 10.04% for the device fabricated with the hybrid CIL. Moreover, all device parameters were simultaneously improved by using this hybrid CIL. The improved open-circuit voltage(VOC) was attributed to the reduced work function of the ITO cathode, whereas the enhancements in fill factor(FF) and short-circuit current density(JSC) were assigned to the increased conductivity and more effective charge extraction and collection at interface. Encouragingly, when the thickness of the hybrid CIL was increased to 80 nm, the resulting device could still keep a PCE of 8.81%, exhibiting less thickness dependence. Considering these advantages, 16 and 93 cm2large-area PSCs modules were successfully fabricated from the hybrid CIL by using doctor-blade coating techniques and yielded a remarkable PCE of8.05% and 4.49%, respectively. These results indicated that the hybrid CIL could be a promising candidate to serve as the cathode interlayer for high-performance large-area inverted PSCs. 相似文献
63.
Two crystalline adducts of triethylenediamine with hydroquinone [N(CH2CH2)3N·C6H4(OH)2,I] and phenol [N(CH2CH2)3N·2C6H5OH,II] have been isolated and characterized by X-ray analysis. ComplexI crystallizes in the monoclinic space groupC2/c, witha=11.944(2),b=9.491(2),c=11.986(2) Å,=121.70(1)°, andZ=4. Both molecular components occupy sites of symmetry 2, and are linked alternately by N H-O hydrogen bonds to form infinite zigzag chains. Crystals ofII are also monoclinic, with space groupP21/c,a=12.987(2),b=6.376(1),c=21.350(3) Å,=106.94(1)°, andZ=4. The structure is composed of discrete hydrogen-bonded molecular aggregates corresponding to the stoichiometric formula. The triethylenediamine moieties in both adducts closely approximate to the idealizedD
3
h conformation. The structures have been refined toR values of 0.097 (I) and 0.092 (II) using, respectively, 479 and 1580 observed MoK data. 相似文献
64.
Qin B Chen X Fang X Shu Y Yip YK Yan Y Pan S Ong WQ Ren C Su H Zeng H 《Organic letters》2008,10(22):5127-5130
Introduction of a continuous hydrogen-bonding network suppressed the conformational flexibility of an oligomeric backbone. Cyclization of a rigidified, suitably sized oligomer led to a circular aromatic pentamer. Its crystal structure determined by X-ray crystallography reveals a pseudo five-fold symmetric planarity in the solid state, which is quite unusual among all the previously described shape-persistent macrocycles and synthetic foldamers with biased conformations enforced by noncovalent forces. 相似文献
65.
Mohamed E Abdul-Rahman PS Doustjalali SR Chen Y Lim BK Omar SZ Bustam AZ Singh VA Mohd-Taib NA Yip CH Hashim OH 《Electrophoresis》2008,29(12):2645-2650
A 35 kDa glycoprotein whose abundance was previously demonstrated to be enhanced in sera of patients with endometrial adenocarcinoma (n = 12), was isolated from pooled sera of three of the cancer patients using champedak galactose-binding lectin affinity chromatography in the present study. Subjecting it to 2-DE and MS/MS, the glycoprotein was identified as the O-glycosylated fragment of inter-alpha-trypsin inhibitor heavy chain H4 (ITIH4). When compared to control sera (n = 17), expression of the 35 kDa ITIH4 cleavage fragment was demonstrated to be significantly enhanced in sera of patients with breast carcinoma (n = 10), epithelial ovarian carcinoma (n = 10), and germ cell ovarian carcinoma (n = 10) but not in patients with nasopharyngeal carcinoma (n = 13) and osteosarcoma (n = 7). The lectin-based electrophoretic bioanalytical method adopted in the present study may be used to assess the physiological relevance of ITIH4 fragmentation and its correlation with different malignancies, their stages and progression. 相似文献
66.
Dr. Shi Xuan Leong Dr. Ya-Chuan Kao Dr. Xuemei Han Dr. Zhong Wei Poh Jaslyn Ru Ting Chen Emily Xi Tan Yong Xiang Leong Dr. Yih Hong Lee Dr. Wei Xuan Teo Prof. George W. Yip Prof. Yulin Lam Prof. Xing Yi Ling 《Angewandte Chemie (International ed. in English)》2023,62(44):e202309610
Molecular recognition of complex isomeric biomolecules remains challenging in surface-enhanced Raman scattering (SERS) spectroscopy due to their small Raman cross-sections and/or poor surface affinities. To date, the use of molecular probes has achieved excellent molecular sensitivities but still suffers from poor spectral specificity. Here, we induce “charge and geometry complementarity” between probe and analyte as a key strategy to achieve high spectral specificity for effective SERS molecular recognition of structural analogues. We employ 4-mercaptopyridine (MPY) as the probe, and chondroitin sulfate (CS) disaccharides with isomeric sulfation patterns as our proof-of-concept study. Our experimental and in silico studies reveal that “charge and geometry complementarity” between MPY's binding pocket and the CS sulfation patterns drives the formation of site-specific, multidentate interactions at the respective CS isomerism sites, which “locks” each CS in its analogue-specific complex geometry, akin to molecular docking events. Leveraging the resultant spectral fingerprints, we achieve > 97 % classification accuracy for 4 CSs and 5 potential structural interferences, as well as attain multiplex CS quantification with < 3 % prediction error. These insights could enable practical SERS differentiation of biologically important isomers to meet the burgeoning demand for fast-responding applications across various fields such as biodiagnostics, food and environmental surveillance. 相似文献
67.
Oleksandr Misiats Oleksandr Stanzhytskyi Nung Kwan Yip 《Journal of Theoretical Probability》2016,29(3):996-1026
In this paper, we investigate the long-time behavior of stochastic reaction–diffusion equations of the type \(\text {d}u = (Au + f(u))\text {d}t + \sigma (u) \text {d}W(t)\), where \(A\) is an elliptic operator, \(f\) and \(\sigma \) are nonlinear maps and \(W\) is an infinite-dimensional nuclear Wiener process. The emphasis is on unbounded domains. Under the assumption that the nonlinear function \(f\) possesses certain dissipative properties, this equation is known to have a solution with an expectation value which is uniformly bounded in time. Together with some compactness property, the existence of such a solution implies the existence of an invariant measure, which is an important step in establishing the ergodic behavior of the underlying physical system. In this paper, we expand the existing classes of nonlinear functions \(f\) and \(\sigma \) and elliptic operators \(A\) for which the invariant measure exists, in particular in unbounded domains. We also show the uniqueness of the invariant measure for an equation defined on the upper half space if \(A\) is the Shrödinger-type operator \(A = \frac{1}{\rho }(\text {div} \rho \nabla u)\) where \(\rho = \text {e}^{-|x|^2}\) is the Gaussian weight. 相似文献
68.
A rapid ion-pair HPLC method was developed and validated for the determination of eight polyprenylated xanthones including three pairs of epimers, namely morellic acid (MA), 30-hydroxygambogic acid (HGA), 30-hydroxyepigambogic acid (HEGA), isogambogic acid (IGA), epiisogambogic acid (EIGA), gambogenic acid (GNA), gambogic acid (GA), and epigambogic acid (EGA), in gamboge resin of Garcinia hanburyi. The separation was performed on a narrow bore C8 column with isocratic elution using a mixture of methanol-ACN-40 mM KH2PO4 buffer (37.5:37.5:25 v/v/v, containing 0.1% tetradecyltrimethylammonium bromide). The newly developed method was used to determine the contents of the eight compounds present in the gamboge. Results showed that GA and EGA are the dominant components of gamboge. The content ratio of each epimer pair remained constant, indicating that the content ratio of epimers can be used as a specific characteristic for the quality control of gamboge. 相似文献
69.
We report new theoretical results and analysis for the transport properties of superconducting UPt3 based on the leading models for the pairing symmetry. We use Fermi surface data and the measured inelastic scattering rate to show that the low-temperature thermal conductivity and transverse sound attenuation in the A- and B-phase of UPt3 are in excellent agreement with pairing states belonging to the two-dimensional orbital E2u representation. 相似文献
70.
Pengfei Zhang Tao Jiang Yuanyuan Li Zheng Zhao Ping Gong Lintao Cai Ryan T. K. Kwok Jacky Wing Yip Lam Xinggui Gu Ben Zhong Tang 《化学:亚洲杂志》2019,14(6):770-774
In this work, we aim to develop cancer cell‐targeting AIE dots based on a polyyne‐bridged red‐emissive AIEgen, 2TPE‐4E, through the combination of metabolic engineering and bio‐orthogonal reactions. Azide groups on a tumor were efficiently produced by intravenous injection of Ac4ManNAz and glycol‐metabolic engineering. These bio‐orthogonal azide groups could facilitate the specific targeting of DBCO‐AIE dots to the tumor cells undergoing metal‐free click reaction in vivo. The efficiency of this targeting strategy could be further improved with the development of new bio‐orthogonal chemical groups with higher reactivity and a large amount of AIEgens could be delivered to the tumor for diagnosis. 相似文献