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191.
Lee Jun Young Hur Min Goo Kong Young Bae Lee Eun Je Yang Seung Dae Choi Pyeong Seok Park Jeong Hoon 《Journal of Radioanalytical and Nuclear Chemistry》2021,330(2):455-460
Journal of Radioanalytical and Nuclear Chemistry - 89Zr is an emerging radionuclide with promising application in nuclear medicine for the non-invasive diagnosis of various cancers with PET... 相似文献
192.
Jeong Hwa Lee Kwang Pyo Kim Young Hwan Kim Hark Kyun Kim Jinsoo Chung 《Journal of mass spectrometry : JMS》2014,49(5):409-416
Histopathologic diagnosis of renal cell carcinoma (RCC) may sometimes be difficult with small biopsy samples. We applied histology‐directed matrix‐assisted laser desorption/ionization mass spectrometry to RCC samples to evaluate whether and how lipid profiles are different between RCC and normal tissue. We evaluated 59 RCC samples and 24 adjacent normal tissue samples collected from patients who underwent surgery. Five peaks were significantly differently expressed (p < 10?7) between RCCs and adjacent normal tissue samples. C24‐OH sulfatide (ST‐OH {18:1/24:0}[M‐H]?; m/z 906.7 in the negative ion mode) and C22‐OH sulfatide (ST‐OH {18:1/22:0}[M‐H]?; m/z 878.6 in the negative ion mode) were most significantly underexpressed in RCC samples, compared with adjacent normal tissue samples. With 100 random training‐to‐test partitions within these samples, the median prediction accuracy (RCC vs. normal) ranged from 96.3% to 100% at p cutoff values for feature selection ranging from 0.001 to 10?7. Two oncocytoma samples were predicted as normal tissue by five lipids that were differentially expressed between RCC and normal tissue at p < 10?7. Clear‐cell, papillary, and chromophobe RCCs were different in lipid profiles. Permutation p‐ values for 0.632+ bootstrap cross‐validated misclassification rates were less than 0.05 for all the classifiers. Thus, lipid profiles differentiate RCC from normal tissue and may possibly classify the histology of RCC. © 2014 The Authors. Journal of Mass Spectrometry published by John Wiley & Sons, Ltd. 相似文献
193.
Optimized precursor ion selection for labile ions in a linear ion trap mass spectrometer and its impact on quantification using selected reaction monitoring
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Hyun‐Seok Lee Kyong‐Oh Shin Sung‐Chan Jo Yong‐Moon Lee Yong‐Hyeon Yim 《Journal of mass spectrometry : JMS》2014,49(12):1234-1238
The fragmentation of fragile ions during the application of an isolation waveform for precursor ion selection and the resulting loss of isolated ion intensity is well‐known in ion trap mass spectrometry (ITMS). To obtain adequate ion intensity in the selected reaction monitoring (SRM) of fragile precursor ions, a wider ion isolation width is required. However, the increased isolation width significantly diminishes the selectivity of the channels chosen for SRM, which is a serious problem for samples with complex matrices. The sensitive and selective quantification of many lipid molecules, including ceramides from real biological samples, using a linear ion trap mass spectrometer is also hindered by the same problem because of the ease of water loss from protonated ceramide ions. In this study, a method for the reliable quantification of ceramides using SRM with near unity precursor ion isolation has been developed for ITMS by utilizing alternative precursor ions generated by in‐source dissociation. The selected precursor ions allow the isolation of ions with unit mass width and the selective analysis of ceramides using SRM with negligible loss of sensitivity. The quantification of C18:0‐, C24:0‐ and C24:1‐ceramides using the present method shows excellent linearity over the concentration ranges from 6 to 100, 25 to 1000 and 25 to 1000 nM, respectively. The limits of detection of C18:0‐, C24:0‐ and C24:1‐ceramides were 0.25, 0.25 and 5 fmol, respectively. The developed method was successfully applied to quantify ceramides in fetal bovine serum. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
194.
Hye Mi Oh Ji Eun Park Jisu Kim Ju Hyun Kim Prof. Youn K. Kang Prof. Young Keun Chung 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(29):9024-9036
A method for the synthesis of bicyclo[4.1.0]heptenes from 1,6‐enynes through Pd‐catalyzed cycloisomerization has been developed. N‐ and O‐tethered 1,6‐enynes were successfully transformed to their corresponding 3‐aza‐ and 3‐oxabicyclo[4.1.0]heptenes in reasonable‐to‐high yields using the catalysts [PdCl2(CH3CN)2]/P(OPh)3 or [Pd(maleimidate)2(PPh3)2] in toluene. The computational calculations using density functional theory indicate that [PdCl2{P(OPh)3}] in the oxidation state PdII acts as the active catalyst species for the formation of 3‐azabicyclo[4.1.0]heptenes through 6‐endo‐dig cyclization. 相似文献
195.
196.
Luminous Butterflies: Efficient Exciton Harvesting by Benzophenone Derivatives for Full‐Color Delayed Fluorescence OLEDs
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Sae Youn Lee Prof. Dr. Takuma Yasuda Dr. Yu Seok Yang Dr. Qisheng Zhang Prof. Dr. Chihaya Adachi 《Angewandte Chemie (International ed. in English)》2014,53(25):6402-6406
Butterfly‐shaped luminescent benzophenone derivatives with small energy gaps between their singlet and triplet excited states are used to achieve efficient full‐color delayed fluorescence. Organic light‐emitting diodes (OLEDs) with these benzophenone derivatives doped in the emissive layer can generate electroluminescence ranging from blue to orange–red and white, with maximum external quantum efficiencies of up to 14.3 %. Triplet excitons are efficiently harvested through delayed fluorescence channels. 相似文献
197.
Nanostructured ZnSe-graphene/TiO2 was synthesized by a hydrothermal-assisted approach. ZnSe-graphene/TiO2 exhibited favorable adsorption of rhodamine B, a wide wavelength absorption range, and efficient charge separation. Reactive oxygen species were generated by the oxidation of 1,5-diphenyl carbazide to 1,5-diphenyl carbazone. The sonocatalytic reaction mechanism was pro-posed. These findings potentially broaden the applications of sonocatalytic technologies. 相似文献
198.
Polyaniline (PANI)/graphene nanosheet (GNS) composites were prepared by a chemical oxidation polymerization. The morphology, structure, and crystallinity of the composites were examined by scanning electron microscopy, transition electron microscopy, and X-ray diffraction. Electrochemical properties were characterized by cyclic voltammetry in 1 M H2SO4 electrolyte. GNS are considered as supporting materials which can provide a large number of active sites. The PANI nanofibers with diameter of 50 nm were homogeneously coated on the surface of GNS. The PANI/GNS composites exhibited a better electrochemical performance than the pure individual components. The PANI/GNS composites showed the highest specific capacitance 923 Fg?1 at 10 mVs?1 compared to 465 Fg?1 for pure PANI and 99 Fg?1 for GNS. 相似文献
199.
Hee-Jeong Cha Se-Yeun Hwang Da-Som Lee Dr. Akula Ravi Kumar Prof. Dr. Yong-Uk Kwon Moritz Voß Eva Schuiten Prof. Dr. Uwe T. Bornscheuer Prof. Dr. Frank Hollmann Prof. Dr. Deok-Kun Oh Prof. Dr. Jin-Byung Park 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(18):7090-7094
Long-chain aliphatic amines such as (S,Z)-heptadec-9-en-7-amine and 9-aminoheptadecane were synthesized from ricinoleic acid and oleic acid, respectively, by whole-cell cascade reactions using the combination of an alcohol dehydrogenase (ADH) from Micrococcus luteus, an engineered amine transaminase from Vibrio fluvialis (Vf-ATA), and a photoactivated decarboxylase from Chlorella variabilis NC64A (Cv-FAP) in a one-pot process. In addition, long chain aliphatic esters such as 10-(heptanoyloxy)dec-8-ene and octylnonanoate were prepared from ricinoleic acid and oleic acid, respectively, by using the combination of the ADH, a Baeyer–Villiger monooxygenase variant from Pseudomonas putida KT2440, and the Cv-FAP. The target compounds were produced at rates of up to 37 U g−1 dry cells with conversions up to 90 %. Therefore, this study contributes to the preparation of industrially relevant long-chain aliphatic chiral amines and esters from renewable fatty acid resources. 相似文献
200.
Mingguang Wu Jiaqin Liao Lingxiao Yu Ruitao Lv Peng Li Wenping Sun Rou Tan Xiaochuan Duan Lei Zhang Fang Li Jiyoung Kim Kang Ho Shin Ho Seok Park Wenchao Zhang Zaiping Guo Haitao Wang Yongbing Tang George Gorgolis Costas Galiotis Jianmin Ma 《化学:亚洲杂志》2020,15(7):995-1013
Carbon is a simple, stable and popular element with many allotropes. The carbon family members include carbon dots, carbon nanotubes, carbon fibers, graphene, graphite, graphdiyne and hard carbon, etc. They can be divided into different dimensions, and their structures can be open and porous. Moreover, it is very interesting to dope them with other elements (metal or non‐metal) or hybridize them with other materials to form composites. The elemental and structural characteristics offer us to explore their applications in energy, environment, bioscience, medicine, electronics and others. Among them, energy storage and conversion are extremely attractive, as advances in this area may improve our life quality and environment. Some energy devices will be included herein, such as lithium‐ion batteries, lithium sulfur batteries, sodium‐ion batteries, potassium‐ion batteries, dual ion batteries, electrochemical capacitors, and others. Additionally, carbon‐based electrocatalysts are also studied in hydrogen evolution reaction and carbon dioxide reduction reaction. However, there are still many challenges in the design and preparation of electrode and electrocatalytic materials. The research related to carbon materials for energy storage and conversion is extremely active, and this has motivated us to contribute with a roadmap on ‘Carbon Materials in Energy Storage and Conversion’. 相似文献