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Your search keyword '"Li, Xiao-Qiong"' showing total 155 results
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155 results on '"Li, Xiao-Qiong"'

5. A 6.7 GHz Methanol Maser Survey II. Low Galactic Latitudes

Author

Yang, Kai, Chen, Xi, Shen, Zhi-Qiang, Li, Xiao-Qiong, Wang, Jun-Zhi, Jiang, Dong-Rong, Li, Juan, Dong, Jian, Wu, Ya-Jun, and Qiao, Hai-Hua

Subjects
Astrophysics - Astrophysics of Galaxies
Abstract

We report the results of our systematic survey for Galactic 6.7 GHz Class II CH$_3$OH maser emission toward a sample of young stellar objects. The survey was conducted with the Shanghai Tianma Radio Telescope (TMRT). The sample consists of 3348 sources selected from the all-sky \emph{Wide-Field Infrared Survey Explorer (WISE)} point source catalog. We have discussed the selection criteria in detail and the detection results of those at high Galactic latitudes (i.e. $|b|>$ 2$^\circ$) in a previous paper (paper I). Here, we present the results from the survey of those at low Galactic latitudes, i.e. $|b|<2^\circ$. Of 1875 selected \emph{WISE} point sources, 291 positions that were actually associated with 224 sources were detected with CH$_3$OH maser emission. Among them, 32 are newly detected. Majority of the newly detected sources are associated with bright WISE sources. The majority of the detected sources (209/224 = 93.3\%) are quite close to the Galactic Plane ($|b|<1^\circ$) and lie on the inner spiral arms with positive LSR velocities. Detection rate and the color-color distribution of our detection are all matched with our anticipation. Combining with detections from previous surveys, we compile a catalogue of 1085 sources with 6.7 GHz CH$_3$OH maser emission in our Galaxy., Comment: 46 pages, 9 figures, 6 tables

Published
2019
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6. A 6.7 GHz Methanol Maser Survey at High Galactic Latitudes

Author

Yang, Kai, Chen, Xi, Shen, Zhi-Qiang, Li, Xiao-Qiong, Wang, Jun-Zhi, Jiang, Dong-Rong, Li, Juan, Dong, Jian, Wu, Ya-Jun, Qiao, Hai-Hua, and Ren, Zhiyuan

Subjects
Astrophysics - Astrophysics of Galaxies
Abstract

We performed a systematic 6.7 GHz Class \uppercase\expandafter{\romannumeral2} methanol maser survey using the Shanghai Tianma Radio Telescope toward targets selected from the all-sky \emph{Wide-Field Infrared Survey Explorer (WISE)} point catalog. In this paper, we report the results from the survey of those at high Galactic latitudes, i.e. $|b|>$ 2$^\circ$. Of 1473 selected \emph{WISE} point sources at high latitude, 17 point positions that were actually associated with 12 sources were detected with maser emission, reflecting the rarity (1$-$2\%) of methanol masers in the region away from the Galactic plane. Out of the 12 sources, 3 are detected for the first time. The spectral energy distribution (SED) at infrared bands shows that these new detected masers occur in the massive star forming regions. Compared to previous detections, the methanol maser changes significantly in both spectral profiles and flux densities. The infrared \emph{WISE} images show that almost all of these masers are located in the positions of the bright \emph{WISE} point sources. Compared with the methanol masers at the Galactic plane, these high-latitude methanol masers provide good tracers for investigating the physics and kinematics around massive young stellar objects, because they are believed to be less affected by the surrounding cluster environment., Comment: 27pages, 8 figures, 3 tables. Published in ApJ

Published
2019
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12. Hyperbranched Chain Hybridization for Artificial Aggregates: Prolonging Intracellular Retention for Image‐Guided Cellular Fate Modulation.

Author

Li, Xiao‐Qiong, Jia, Yi‐Lei, Wang, Zhong‐Xia, Zhang, Yu‐Wen, Chen, Hong‐Yuan, and Xu, Jing‐Juan

Subjects
*CANCER cells, *PROOF of concept, *BIOCOMPATIBILITY, *DNA, *SIGNALS & signaling
Abstract

Designing dynamic assemblies in living cells is crucial for creating organelle‐like structures, yet precisely controlling their morphological transitions in response to specific signals is a significant challenge. In this study, a DNA framework is combined with hybridization chain reaction (HCR) to achieve specific assembly of hyperbranched aggregates in cancer cells. HCR, distinguished for its signal amplification and linear extension capabilities, enables the morphological transition of precursors to be specifically triggered by trace amounts of endogenous microRNA‐21 (miR‐21). The spatial constraints of the framework and the diversity of hairpin orientations significantly accelerate the assembly kinetics of hyperbranched networks, and the resulting micrometer‐scale aggregates possess enhanced intracellular retention capabilities. Introducing Ce6 molecules as a proof of concept, the regulatory function of aggregates can be activated under light irradiation and remains effective over a long period. The probe we constructed demonstrates good stability and biocompatibility, offers easy functionalization, and works inside cells long‐term, making it an ideal candidate material for the construction of organelle‐like structures. [ABSTRACT FROM AUTHOR]

Published
2024
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16. Research status of epichlorohydrin production process.

Author

QI Fu-qiang, ZHANG Zhen-tao, YANG Jun-ling, WU Zhen-qun, ZHANG Hua-fu, and LI Xiao-qiong

Subjects
MANUFACTURING processes, EPICHLOROHYDRIN, PRODUCTION methods, EPOXIDATION, ALLYL chloride
Abstract

The present status and development of ECH production are summarized, the advantages and disadvantages of different process routes are analyzed, the catalyst system and production process of ECH production by glycerol method and direct epoxidation of chloropropene are mainly introduced. Due to the effective utilization of biomass resources and simple production process. Glycerol process is a mature production process after propylene high-temperature chlorination process; as a green synthesis process of ECH, the direct epoxidation of chloropropene should focus on the design of low-cost catalysts and the integration of processes to reduce consumption. [ABSTRACT FROM AUTHOR]

Published
2024

20. Interface Engineering of Copper Nanocluster Assemblies with White‐Light Emission.

Author

Wang, Zhong‐Xia, Gao, Hang, Li, Xiao‐Qiong, Jia, Yi‐Lei, Wang, Ting, Cheng, Qiu‐Yue, Kang, Bin, Chen, Hong‐Yuan, and Xu, Jing‐Juan

Subjects
SURFACE chemistry, DENSITY functional theory, MASS spectrometry, COPPER
Abstract

Construction of white‐light emitters is of great importance in practical applications but is challenging for metal nanoclusters. Herein, arginine (Arg)‐mediated copper nanoclusters (Cu NCs) assemblies with white‐light emission (WLE) are reported for the first time. The multidentate ligand, Arg, not only effectively tailors the high stability and locally‐excited emission (LES) of aqueous phase Cu NCs, but also bridges 1‐naphthalenol methylcarbamate (NMC) to generate a blue emitter via through‐space interactions (TSIs), resulting in a stable mixed light. Density functional theory calculation and mass spectrum further confirm that Arg can allow for the formation of strong hydrogen‐bonds with the ligand 2,4‐diaminotoluene of Cu NCs, and formation of TSIs‐based complexes with NMC. More importantly, pure white‐light emission (WLE) with Commission Internationale de L'Eclairagecoordination (0.30, 0.31) is observed by regulating the ratio between Arg and the interfacial ligand of NMC. The findings not only provide a new perspective for the construction of WLE emitters via interface modification chemistry but also open a window to gain insight into the mechanism of interface engineering. [ABSTRACT FROM AUTHOR]

Published
2023
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39. A 6.7 GHz Methanol Maser Survey at High Galactic Latitudes

Author

Yang, Kai, primary, Chen, Xi, additional, Shen, Zhi-Qiang, additional, Li, Xiao-Qiong, additional, Wang, Jun-Zhi, additional, Jiang, Dong-Rong, additional, Li, Juan, additional, Dong, Jian, additional, Wu, Ya-Jun, additional, Qiao, Hai-Hua, additional, and Ren, Zhiyuan, additional

Published
2017
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40. Tianma 65-m telescope detection of new OH maser features towards the water fountain source IRAS 18286−0959

Author

Chen, Xi, primary, Shen, Zhi-Qiang, additional, Li, Xiao-Qiong, additional, Yang, Kai, additional, Nakashima, Jun-ichi, additional, Wu, Ya-Jun, additional, Zhao, Rong-Bin, additional, Li, Juan, additional, Wang, Jun-Zhi, additional, Jiang, Dong-Rong, additional, Wang, Jin-Qing, additional, Li, Bin, additional, Zhong, Wei-Ye, additional, and Yung, Bosco H. K., additional

Published
2017
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50. Preparation of Nano-TiO2 Modified Temperature-Responsive Chromatographic Materials for Enrichment of Phosphopeptides

Author

Pang, Xin Zhu, Feng, Jin Sheng, Wang, Di, Li, Bo, Li, Xiao Qiong, Deng, Yu Lin, and Dai, Rong Ji

Abstract

Chromatographic stationary phases with specific capturing phosphoproteins is widely used in biological sample pretreatment. However, when captured protein is released, it is required to change the pH of the mobile phase or to use an eluent. Usually, the mobile phase or eluent are salt solutions with high concentration and extreme pH or toxic organic reagents. In this situation, these reagents will destroy the activity and structure of phosphorylated proteins. In addition, the mobile phase after switching the column takes longer time to restore the balance, reducing the experimental efficiency. In order to solve the these problems, we introduce temperature-reponsive materials into the chromatographic stationary phase to achieve the capture and release of phosphorylated proteins by changing the temperature only, in which we use water as the mobile phase. This approach overcomes the drawbacks of traditional methods, and makes the separation process safe and simple. Based on the surface initiated Reversible Addition Fragmentation Chain Transfer Polymerization (SI-RAFT) method, silica@pNIPAAm-nanoTiO2, a kind of Metal Oxide Affinity Chromatography, was synthesized by the rapid introduction of functional groups. The synthesis of silica@pNIPAAm-nanoTiO2 was confirmed by infrared and X-ray photoelectron spectroscopy. The grafting rate and the lowest critical temperature were measured by TG and DSC. The results showed that the material had qualified temperature-sensitive properties. The grafting conformation and mobile phase pH of the material were optimized before testing the properties and found that when the material grafting ratio was 10% -15%, the graft density was 30%, and the mobile phase pH was 6, it had the best separate effect. Finally, the material successfully achieved the capture and release of adenosine triphosphate and casein phosphopeptides.

Published
2018
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