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71.
72.
Xiaoxuan Ma Na Li Shikun Liu Kun Zhang Caixia Chi Jiupeng Zhao Xiaoxu Liu Yao Li 《Journal of Solid State Electrochemistry》2018,22(9):2801-2809
In this work, a novel pyrrolic nitrogen-doped carbon sandwiched monolayer MoS2 hybrid was prepared. This sandwiched hybrid vertically anchors on graphene oxide as anode materials for sodium-ion batteries. Such electrode was fabricated by facile ionic liquid-assisted reflux and annealing methods. Owing to rational structure and enhancement from pyrrolic nitrogen dopant, this unique MoS2/C-graphene hybrid exhibits reversible specific capacity of 486 mAh g?1 after 1000 cycles with a low average fading capacity of 0.15 mAh g?1 (fading cyclic rate of ca. 0.03% per cycle). A capacity of 330 mAh g?1 is remained at the current densities of 10.0 A g?1. The proposed strategy provides a convenient way to create new pyrrolic nitrogen-doped hybrids for energy field and other related applications. 相似文献
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Here, N,N′-bis(4-hydroxylsalicylidene)-p-phenylenediamine (BSPD-OH), N,N′-bis(4-methoxylsalicylidene)-p-phenylenediamine (BSPD-OMe) and N,N′-bis(salicylidene)-p-phenylenediamine (BSPD), which belong to the same category of aggregation-induced emission (AIE) compounds based on Schiff base reactions, were synthesized and applied as new matrices in the analysis of small molecules by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). This type of AIE compounds can be good MALDI matrices. Conventional organic matrices often produce large amounts of matrix ions, hindering the analysis of low molecular weight (LMW) compounds. However, these AIE compounds generate few matrix ions and less background interference because their presence as aggregates decreases the generation of matrix interference. The sensitivity of the AIE matrix is high because the aggregates can improve the absorption of the applied laser emissions. We can regulate the ionization efficiency of the AIE matrix by changing its aggregation state. During this study, BSPD-OH exhibited better ionization efficiency than the other two AIE matrices because it has more phenolic hydroxyl groups. BSPD-OH was successfully applied to the analysis of various LMW compounds including amino acids, organic amine compounds, isoquinoline compounds and fluoroquinolones compounds. This material also can be employed during the qualitative and quantitative analysis of LMW metabolites in human urine without requiring complicated separation processes. 相似文献
75.
A simple and facile solution route has been developed for phase and morphology controllable synthesis of antimony trioxide (Sb2O3) microcrystals. Orthorhombic phase and cubic phase Sb2O3 microcrystals have been selectively synthesized in high yield. The products were characterized by powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). The as-obtained microcrystals exhibited a variety of morphologies and structures, such as microspindles, nanoplates, and octahedra. Several experimental parameters have been investigated to gain morphology control of Sb2O3 microcrystals. Based on the time-dependent experimental results, an aggregation, and recrystallization mechanism was proposed to describe the formation process of these novel microstructures. 相似文献
76.
Yutao Yang Ming Ma Lei Shen Jusung An Eunji Kim Hongmei Liu Ming Jin Shuxiang Wang Jinchao Zhang Prof. Jong Seung Kim Prof. Caixia Yin 《Angewandte Chemie (International ed. in English)》2023,62(40):e202310408
Cerebral ischemia-reperfusion injury (CIRI) is intimately associated with the redox regulation of biothiol, a crucial antioxidant marker that precludes the onset of ROS. We designed a novel fluorescent probe, DCI-Ac-Py , showing various physicochemical properties, such as high selectivity, exceptional signal-to-noise ratio, near-infrared (NIR) optical window, and blood–brain barrier (BBB) penetrability, for detecting biothiols in the brain. The picolinate serves as a specific recognition group that is rapidly activated by biothiol and undergoes nucleophilic substitution with the adjacent acrylic ester to yield the desired NIR probe. Additionally, the probe's lipid solubility is improved through the inclusion of halogen atoms, which aids in penetrating the BBB. Using DCI-Ac-Py , we investigated changes of biothiols in vivo in the brains of mice during CIRI. We found that biothiol-mediated NF-kB classical (P65-related) and nonclassical (RelB-related) pathways contribute to abundant ROS production induced by CIRI and that biothiols are involved in redox regulation. These findings provide new insights into the study of CIRI and shed light on the physiological and pathological mechanisms of biothiols in the brain. 相似文献
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78.
Xinhua Li Caixia Wang Hongping Xiao Charles N. Moorefield 《Supramolecular chemistry》2016,28(11-12):907-912
Two simple organic compounds, 5-nitroisophthalic acid (npa) and 4,4′-bipyridine (bpy), were used as building blocks for supramolecular self-assembly by hydrothermal synthesis. SEM, TEM, and XRD were used to analyse the multi-step assembly process in which npa and bpy assembled into nanotubes (or nanobelts) of about 30–100 nm in diameter and several millimetres in length and microtubes (or microbelts). The tubes then further assembled to form complex ordered structures, such as pom-pom-shaped and flower-like mesostructures. 相似文献
79.
Runqiang Liu Ning Zhao Ping Liu Caixia An Zhaoxun Lian 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(5):451-455
π‐Conjugated organic materials exhibit high and tunable nonlinear optical (NLO) properties, and fast response times. 4′‐Phenyl‐2,2′:6′,2′′‐terpyridine (PTP) is an important N‐heterocyclic ligand involving π‐conjugated systems, however, studies concerning the third‐order NLO properties of terpyridine transition metal complexes are limited. The title binuclear terpyridine CoII complex, bis(μ‐4,4′‐oxydibenzoato)‐κ3O,O′:O′′;κ3O′′:O,O′‐bis[(4′‐phenyl‐2,2′:6′,2′′‐terpyridine‐κ3N,N′,N′′)cobalt(II)], [Co2(C14H8O5)2(C21H15N3)2], (1), has been synthesized under hydrothermal conditions. In the crystal structure, each CoII cation is surrounded by three N atoms of a PTP ligand and three O atoms, two from a bidentate and one from a symmetry‐related monodentate 4,4′‐oxydibenzoate (ODA2−) ligand, completing a distorted octahedral coordination geometry. Neighbouring [Co(PTP)]2+ units are bridged by ODA2− ligands to form a ring‐like structure. The third‐order nonlinear optical (NLO) properties of (1) and PTP were determined in thin films using the Z‐scan technique. The title compound shows a strong third‐order NLO saturable absorption (SA), while PTP exhibits a third‐order NLO reverse saturable absorption (RSA). The absorptive coefficient β of (1) is −37.3 × 10−7 m W−1, which is larger than that (8.96 × 10−7 m W−1) of PTP. The third‐order NLO susceptibility χ(3) values are calculated as 6.01 × 10−8 e.s.u. for (1) and 1.44 × 10−8 e.s.u. for PTP. 相似文献
80.
Lanthanide(III) luminescent hybrid materials based on the layered hectorite have been successfully prepared, showing tunable emission colors as well as white light by varying the molar ratio between Eu3+ and Tb3+. 相似文献