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101.
102.
Synthesis of Alkyl‐Substituted Quinoxaline‐Based Copolymers Along with Photophysical Property Modulation for Polymer Solar Cells
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Yeongkwon Kang Rajalingam Agneeswari Jihoon Lee Ji Hyeon Kwon Vellaiappillai Tamilavan Seong Soo Park Sung Heum Park Youngeup Jin 《Macromolecular chemistry and physics.》2018,219(15)
A series of alkyl‐substituted quinoxaline‐based copolymers are prepared and their properties are studied. Stille copolymerization of 2,5‐bis(trimethylstannyl)thiophene (M3) with different ratios of 2,7‐dibromo‐9,9‐dioctyl‐9H‐fluorene (M4) and 5,8‐dibromo‐6,7‐difluoro‐2,3‐didodecylquinoxaline (M1) affords five new random copolymers, labeled P1–P5. Suzuki copolymerization of 4,5,5‐tetramethyl‐2‐[2‐(4,4,5,5‐tetramethyl‐1,3,2‐dioxaborolan‐2‐yl)‐9,9‐dioctyl‐9H‐fluoren‐7‐yl]‐1,3,2‐dioxaborolane (M5) and 5,8‐bis(5‐bromothiophen‐2‐yl)‐2,3‐didodecyl‐6,7‐difluoroquinoxaline (M2) yielded a new alternating copolymer, labeled P6. All copolymers show high thermal stability, and the 5% weight loss temperature is above 400 °C. The estimated optical bandgap (E g) values of random copolymers P1–P5 (E g ≈ 1.93, 1.97, 1.97, 2.02, and 2.08 eV, respectively) are found to be relatively lower than that of alternating copolymer P6 (E g ≈ 2.14 eV). All copolymers P1–P6 exhibit deep highest occupied molecular orbital (HOMO) energy levels, and the determined HOMO levels are ?5.65, ?5.67, ?5.67, ?5.60, ?5.59, and ?5.66 eV, respectively. The maximum power conversion efficiencies of polymer solar cells made with individual copolymers P1–P6 as a donor materials and PC70BM as an acceptor are 3.98, 2.91, 3.33, 3.55, 3.07, and 2.78%, respectively. 相似文献
103.
In this paper, experiments were conducted on the effects of aesthetic and durability of three representative surface protective material under accelerated weathering test for 5000 h. First, the adaptability of the surface protective material coating to the substrate was proven by examining the aesthetic properties and the water permeability of the building materials. Second, the pollutant resistance of the surface protective material coating to artificial stain was assessed using xenon-arc light. The result shows that the appearance of the silane types did not change significantly, and the water permeability was improved. In addition, the silicate types did not improve water permeability and the surface color was changed. Fluor- resin types effectively improved the water permeability, but the surface color became dark. Sample measurements showed changes in the average width of the contamination after weathering, with an increase after spray cleaning and ultrasonic cleaning. However, it was observed that after washing the pollution average width of all specimens due to weathering at 5000 h was almost as much or smaller than the initial value. 相似文献
104.
105.
A real-time kinase assay method based on a ratiometric fluorescence probe that can be applied to various small-molecule kinases is described herein. The probe can trace the reversible interchange of ATP and ADP, which is a common phenomenon in most small-molecule kinase reactions, by a ratiometric fluorescence change. This property facilitates the monitoring of phosphorylation and dephosphorylation in small-molecule kinases, whereas most of the existing methods focus on one of these reactions. To prove the applicability of this method for small-molecule kinase assays, hexokinase and creatine kinase, which phosphorylate and dephosphorylate substrates, respectively, were analyzed. The ratiometric fluorescence change was correlated with the enzyme activity, and the inhibition efficiencies of the well-known inhibitors, N-benzoyl-d-glucosamine and iodoacetamide, were also monitored. Notably, the change in fluorescence can be observed with a simple light source by the naked eye.A versatile assay system that can be trace both phosphorylation and dephosphorylation by small molecule kinase is demonstrated, and can be applied regardless of substrate diversity. 相似文献
106.
Joo Myung Lee Tae-Min Rhee Joo-Yong Hahn Hyun Kuk Kim Jonghanne Park Doyeon Hwang Ki Hong Choi Jihoon Kim Taek Kyu Park Jeong Hoon Yang Young Bin Song Jin-Ho Choi Seung-Hyuk Choi Bon-Kwon Koo Young Jo Kim Shung Chull Chae Myeong Chan Cho Chong Jin Kim Myung Ho Jeong 《Journal of the American College of Cardiology》2018,71(8):844-856
Background
Recent trials demonstrated a benefit of multivessel percutaneous coronary intervention (PCI) for noninfarct-related artery (non-IRA) stenosis over IRA-only PCI in patients with ST-segment elevation myocardial infarction (STEMI) multivessel disease. However, evidence is limited in patients with cardiogenic shock.Objectives
This study investigated the prognostic impact of multivessel PCI in patients with STEMI multivessel disease presenting with cardiogenic shock, using the nationwide, multicenter, prospective KAMIR-NIH (Korea Acute Myocardial Infarction-National Institutes of Health) registry.Methods
Among 13,104 consecutive patients enrolled in the KAMIR-NIH registry, we selected patients with STEMI with multivessel disease presenting with cardiogenic shock and who underwent primary PCI. Primary outcome was 1-year all-cause death, and secondary outcomes included patient-oriented composite outcome (a composite of all-cause death, any myocardial infarction, and any repeat revascularization) and its individual components.Results
A total of 659 patients were treated by multivessel PCI (n = 260) or IRA-only PCI (n = 399) strategy. The risk of all-cause death and non-IRA repeat revascularization was significantly lower in the multivessel PCI group than in the IRA-only PCI group (21.3% vs. 31.7%; hazard ratio: 0.59; 95% confidence interval: 0.43 to 0.82; p = 0.001; and 6.7% vs. 8.2%; hazard ratio: 0.39; 95% confidence interval: 0.17 to 0.90; p = 0.028, respectively). Results were consistent after multivariable regression, propensity-score matching, and inverse probability weighting to adjust for baseline differences. In a multivariable model, multivessel PCI was independently associated with reduced risk of 1-year all-cause death and patient-oriented composite outcome.Conclusions
Of patients with STEMI and multivessel disease with cardiogenic shock, multivessel PCI was associated with a significantly lower risk of all-cause death and non-IRA repeat revascularization. Our data suggest that multivessel PCI for complete revascularization is a reasonable strategy to improve outcomes in patients with STEMI with cardiogenic shock. 相似文献107.
Eun Young Park Da Hwan Lee Thi Na Le Chol-Min Shin Jihoon Lee Min Chul Suh 《RSC advances》2021,11(47):29115
We designed and synthesized a new host material with a highly soluble and thermally stable indenocarbazole derivative (7,7-dimethyl-5-phenyl-2-(9-phenyl-9H-carbazol-3-yl)-5,7-dihydro-indeno[2,1-b]carbazole) that can make green phosphorescent organic light-emitting diodes (PHOLEDs) in a solution process. In particular, these are used in a blue common layer structure in which green and red-emitting layers are formed by a solution process and blue common layers are thermally evaporated. The new host material possesses excellent hole transport capability and high triplet energy (T1). Mainly we designed the hole dominant material to keep the exciton forming area away from the hole transport layer (HTL) and emitting layer (EML) interface, an interfacial mixing area to improve device performance. As a result, the greatest lifetime of 1300 hours was achieved and a high current efficiency of up to 66.3 cd A−1 was recorded when we used the optimized device structure of a 5 nm thick bipolar exciton blocking layer (B-EBL). It may be a good agreement of exciton confinement and reduced electron accumulation at the HTL and EML interface.We designed and synthesized a new host material with a highly soluble and thermally stable indenocarbazole derivative that can make green phosphorescent organic light-emitting diodes (PHOLEDs) in a solution process. 相似文献
108.
So Yeon Won Jihoon Cha Hyun Seok Choi Young Dae Kim Hyo Suk Nam Ji Hoe Heo Seung-Koo Lee 《Korean journal of radiology》2022,23(3):333
ObjectiveIntracranial atherosclerotic stroke occurs through various mechanisms, mainly by artery-to-artery embolism (AA) or branch occlusive disease (BOD). This study evaluated the spatial relationship between middle cerebral artery (MCA) plaques and perforating arteries among different MCA territory infarction types using vessel wall magnetic resonance imaging (VW-MRI).Materials and MethodsWe retrospectively enrolled patients with acute MCA infarction who underwent VW-MRI. Thirty-four patients were divided into three groups according to infarction pattern: 1) BOD, 2) both BOD and AA (BOD-AA), and 3) AA. To determine the factors related to BOD, the BOD and BOD-AA groups were combined into one group (with striatocapsular infarction [BOD+]) and compared with the AA group. To determine the factors related to AA, the BOD-AA and AA groups were combined into another group (with cortical infarction [AA+]) and compared with the BOD group. Plaque morphology and the spatial relationship between the perforating artery orifice and plaque were evaluated both quantitatively and qualitatively.ResultsThe plaque margin in the BOD+ group was closer to the perforating artery orifice than that in the AA group (p = 0.011), with less enhancing plaque (p = 0.030). In the BOD group, plaques were mainly located on the dorsal (41.2%) and superior (41.2%) sides where the perforating arteries mainly arose. No patient in the AA group had overlapping plaques with perforating arteries at the cross-section where the perforator arose. Perforating arteries associated with culprit plaques were most frequently located in the middle two-thirds of the M1 segment (41.4%). The AA+ group had more stenosis (%) than the BOD group (39.73 ± 24.52 vs. 14.42 ± 20.96; p = 0.003).ConclusionThe spatial relationship between the perforating artery orifice and plaque varied among different types of MCA territory infarctions. In patients with BOD, the plaque margin was closer and blocked the perforating artery orifice, and stenosis degree and enhancement were less than those in patients with AA. 相似文献
109.
High-pressure torsion (HPT) is a severe plastic deformation technique where a sample is subjected to torsional shear straining under a high hydrostatic pressure. The HPT method is usually employed to create ultrafine-grained nano-structures, making it widely used in processing many kinds of materials such as metals, glasses, biological materials, and organic compounds. Most of the published HPT results have been focused on the microstructural development of non-magnetic materials and their influence on the mechanical properties. The HPT processing of magnetic materials and its influence on the structural and magnetic properties have attracted increasing research interest recently. This review describes the application of HPT to magnetic materials and our recent experimental results on Mn3O4, Mn4N, and MnAl-based alloys. After HPT, most magnetic materials exhibit significantly reduced grain size and substantially enhanced coercivity. 相似文献
110.
Seong Hoon Bae Jihoon Choi Jae Young Choi 《Clinical and experimental otorhinolaryngology》2022,15(1):77
ObjectivesCommon cavity deformity is a rare congenital bony labyrinth malformation associated with profound hearing loss. Cochlear implants are widely used for hearing rehabilitation for common cavity deformities; however, the reported prognosis is poor. Due to the deformed anatomical structure, it is important to consider the position of the electrodes to maximize the performance of the cochlear implant. The present study discusses the impact of electrode placement on hearing outcomes.MethodsA retrospective medical chart review of eight common cavity deformity patients (10 cochlear implants) who received cochlear implants was performed at a single university hospital. In all eight patients, implant surgery was performed using single-slit labyrinthotomy. Electrodes wer e manually bent before insertion to prevent misplacement and to reduce physical damage to the neuroepithelium.ResultsFour of the 10 electrodes were misplaced, with their tips placed in the anterior semicircular canal or internal auditory canal. However, after implant surgery, all patients—including those with misplaced electrodes—gained auditory perception and improved hearing function. One patient who had electrodes that did not contact the inner wall of the cavity showed limited activity of the electrodes (27%) compared to others (64%–100%).ConclusionProper contact of the electrode with the inner wall was more likely to be important for cochlear implant success in cases of common cavity deformity than appropriate placement of the electrode tip. 相似文献