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2. Sub-40nm Nanogratings Self-Organized in PVP-based Polymer Composite Film by Photoexcitation and Two Sequent Splitting under Femtosecond Laser Irradiation

Author

Chen, Li-Yun, Guo, Cheng-Cheng, Pan, Ming-Ming, Lai, Chen, Wang, Yun-Xia, Liao, Guo-Cai, Ma, Zi-Wei, Zhang, Fan-Wei, Suriyaprakash, Jagadeesh, Guo, Lijing, Akinoglu, Eser, Li, Qiang, and Wu, Li-Jun

Subjects
Physics - Optics, Physics - Applied Physics
Abstract

Laser-induced periodic surface structures (LIPSSs) on various materials have been extensively investigated because of their wide applications. The combination of different materials allows for greater freedom in tailoring their functions and achieving responses not possible in a homogeneous material. By utilizing a femtosecond (fs) laser to irradiate the Fe-doped Polyvinyl Pyrrolidone (PVP) composite film, highly regular ultrafine nanogratings (U-nanogratings) with a period as small as 35.0 ($\pm$ 2.0) nm can be self-organized on the surface with extremely high efficiency. The period of the U-nanogratings can be controlled by varying the scanning speed of the laser beam (deposited energy) and the thickness of the composite film. Based on the experimental, theoretical, and simulation results, we propose a two-step formation mechanism: composite film excitation and two sequent grating-splitting. The high photosensitivity and low glass transition temperature of the composite film facilitate the fabrication of the ultrafine nanostructures. The proposed design method for the composite material and fabrication process could not only provide a strategy for obtaining highly regular U-nanogratings, but also offer a platform to explore the interaction physics between ultra-short pulses and matter under extreme conditions.

Published
2022
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9. Analysis of main volatile aroma components of chicory

Author

ZHANG Feng-mei, PU Ruan, WU Li-jun, JIANG Wei, and TANG Shi-yun

Subjects
chicory extract, hs-spme-gc/ms, volatility, aroma components, odor activity value, Food processing and manufacture, TP368-456
Abstract

Objective: To study the main volatile aroma components in chicory extracts. Methods: The volatile components in chicory extracts were analyzed by headspace-solid phase microextraction-gas chromatography-mass spectrometry （HS-SPME-GC/MS）, the content of volatile components was analyzed by semi quantitative method, and the main volatile aroma components were analyzed by volatile component content/sensory threshold value （odor activity value, OAV）. Results: A total of 78 volatile components were detected in the sample. The sequence of volatile components with relative content＞1% was propylene glycol＞5-hydroxymethylfurfural＞acetic acid＞1,2-propanediol dicarboxylate＞formic acid＞1,2-propanediol 2-acetate; The aroma activity values of 24 aroma components were analyzed. The main volatile aroma components with OAV greater than 1 were acetic acid＞methyl isobutyrate＞ethyl cinnamate＞formic acid＞methyl cyclopentaenol ketone＞2,4-di-tert-butylphenol＞5-methylfurfural＞propylene glycol. Conclusion: The main volatile components in chicory extract were propylene glycol, 5-hydroxymethylfurfural, acetic acid, 1,2-propanediol dicarboxylate, formic acid, 1,2-propanediol 2-acetate, and the main volatile aroma components are acetic acid, methyl isobutyrate, ethyl cinnamate, formic acid, methyl cyclopentanol ketone, 2,4-di-tert-butylphenol, 5-methylfurfural, propylene glycol.

Published
2023
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11. Research progress of reference substance for steroid hormone in food matrix

Author

WU Li-jun, YIN Ying, DAI Li-xue, YU Li-bo, LI Cun, and PENG Tao

Subjects
ood, steroid hormone, matrix reference material, technical route, Food processing and manufacture, TP368-456
Abstract

This review summarized the technical route and development process of matrix reference materials in China, and the current research progress of steroid hormone matrix reference materials were also introduced. The problems existing in the development and production of matrix reference materials in China and the future development are prospectsed.

Published
2023
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22. Three-dimensional Orientation Sensors by Defocused Imaging of Gold Nanorods through an Ordinary Wide-Field Microscope

Author

Li, Tao, Li, Qiang, Chen, Xiao-Jun, Xu, Yi, Dai, Qiaofeng, Liu, Hai-Ying, Lan, Sheng, and Wu, Li-Jun

Subjects
Physics - Optics, Physics - Chemical Physics
Abstract

Gold (Au) nanoparticles particularly nanorods are actively exploited as imaging probes because of their special nonblinking and nonbleaching absorption, scattering and emitting properties that arise from the excitation of surface plasmons. Herein, we report a novel orientation sensor at nanoscale by defocused imaging of single Au nanorods (AuNRs) through an ordinary wide-field optical microscope. By simultaneously recording defocused images and two-photon luminescence intensities for a large number of single AuNRs, we correlate their defocused images with their three-dimensional spatial orientations. As many AuNRs can be monitored in parallel, defocused imaging of single AuNRs is a high throughput sensing technique that allows us to obtain their spatial orientations within one frame in situ and real-time. The probe size can be down to several nanometers, which is highly desirable in order to minimize any potential interference from the probe itself. Furthermore, the sensing property is insensitive to the excitation polarization and the distribution of the probe aspect ratio, which allows AuNRs of any length in a proper regime to be used as orientation sensors without changing the laser frequency and polarization. These unique features make the orientation probes proposed here outstanding candidates for optical imaging and sensing in material science and biology.

Published
2011

23. Assembling of three-dimensional crystals by large nonequilibrium depletion force

Author

Deng, Hai-Dong, Sun, Ting, Fu, Zhi-Cheng, Liu, Hai-Ying, Dai, Qiao-Feng, Wu, Li-Jun, Lan, Sheng, and Achanta, Venu Gopal

Subjects
Condensed Matter - Soft Condensed Matter, Condensed Matter - Materials Science, Physics - Atmospheric and Oceanic Physics, Physics - Optics
Abstract

We propose and demonstrate a method to achieve large effective Soret coefficient in colloids by suitably mixing two different particles, e.g., silica beads and Fe3O4 nanoparticles. It is shown that the thermophoretic motion of Fe3O4 nanoparticles out of the heating region results in a large nonequlibrium depletion force for silica beads. Consequently, silica beads are driven quickly to the heating region, forming a three-dimensional crystal with few defects and dislocations. The binding of silica beads is so tight that a colloidal photonic crystal can be achieved after the complete evaporation of solvent, water. Thus, for fabrication of defect free colloidal PCs, periodic structures for molecular sieves, among others, the proposed technique could be a low cost alternative. In addition as we use biocompatible materials, this technique could be a tool for biophysics studies where the potential of large effective Soret coefficient could be useful., Comment: 13 pages, 7 figures

Published
2010
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25. Causes of death in hospitalized patients with systemic lupus erythematosus: a 10-year multicenter nationwide Chinese cohort

Author

Wu, Xin-yao, Yang, Min, Xie, Yue-sheng, Xiao, Wei-guo, Lin, Jin, Zhou, Bin, Guan, Xin, Luo, Cai-nan, Che, Nan, Liu, Xing-zhen, Wang, Chao, Teng, Jia-lin, Cheng, Xiao-bing, Ye, Jun-na, Su, Yu-tong, Shi, Hui, Yin, Yu-feng, Liu, Meng-ru, Sun, Yue, Hu, Qiong-Yi, Zhou, Zhuo-chao, Chi, Hui-hui, Liu, Yi, Zhang, Xiao, Chen, Jin-wei, Zhang, Miao-jia, Zhao, Dong-bao, Yang, Cheng-de, Wu, Li-jun, and Liu, Hong-lei

Published
2019
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26. Capturing circulating tumor cells of hepatocellular carcinoma.

Author

Wu, Li-Jun, Pan, Yi-Da, Pei, Xiao-Yu, Chen, Hong, Nguyen, Samantha, Kashyap, Akshay, Liu, Jie, and Wu, Jian

Subjects
Liver Cancer
Abstract

Early metastases of hepatocellular carcinoma (HCC) may be detected by the isolation of circulating tumor cells (CTCs) in the bloodstream. During the course of therapeutic attempts, monitoring CTC changes in patients with HCC is helpful for the efficacy assessment. Nevertheless, the markers used for the detection, such as α-feto protein, asialoglycoprotein receptor or epithelial cell adhesion molecule, CD133 or CD90, are not specific for HCC CTCs. In spite of these limitations, a timely determination of the existence of CTCs will be beneficial for the monitoring of distant metastases, the evaluation of therapeutic attempts, and the prediction of prognosis.

Published
2012

40. Dietary intake and risk of rheumatoid arthritis—a cross section multicenter study

Author

He, Jing, Wang, Yu, Feng, Min, Zhang, Xia, Jin, Yue-Bo, Li, Xue, Su, Lin-Chong, Liu, Shuang, Wang, Ai-Xue, Chen, Xiao-Mei, Wu, Li-Jun, Yu, Xiao-Xia, Xu, Ning, Liu, Xiang-Yuan, Yan, Hui-Ming, Wang, Yong-Fu, Jia, Bin, Li, Jun-Fang, Tao, Jie-Mei, Zhang, Feng-Xiao, Yu, Ping, Cui, Liu-Fu, Yang, Jing, Li, Zhen-Bin, Xie, Jian-Li, Wei, Ping, Sun, Wen-Wen, Gong, Lu, Cheng, Yong-Jing, Huang, Ci-Bo, Wang, Xiao-Yuan, Wang, Yi, Guo, Hui-Fang, Jin, Hong-Tao, Liu, Xia, Wang, Guo-Chun, Wang, Yan-Hua, He, Lan, Zhao, Yi, Li, Xiao-Xia, Zhang, Yan, Guo, Jian-Ping, and Li, Zhan-Guo

Published
2016
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49. Synthesis of Pyrimidines from Dinitrogen and Carbon

Author

Shi, Xianghui, primary, Wang, Qianru, additional, Qin, Chao, additional, Wu, Li-Jun, additional, Chen, Yuanjin, additional, Wang, Gao-Xiang, additional, Cai, Yongli, additional, Gao, Wenbo, additional, He, Teng, additional, Wei, Junnian, additional, Guo, Jianping, additional, Chen, Ping, additional, and Xi, Zhenfeng, additional

Published
2022
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50. From Dinitrogen to N‐Containing Organic Compounds: Using Li2CN2 as a Synthon.

Author

Wu, Li‐Jun, Wang, Qianru, Guo, Jianping, Wei, Junnian, Chen, Ping, and Xi, Zhenfeng

Subjects
*ORGANIC compounds, *CALCIUM cyanamide, *RING formation (Chemistry), *SUBSTITUTION reactions, *TRIAZOLE derivatives
Abstract

Through the synergies of a heterogeneous synthetic approach and a homogeneous synthetic methodology, N‐containing organic compounds can be synthesized via activated N‐containing species prepared from N2 gas and suitable carbon sources. From N2, carbon, and LiH, we have previously succeeded in the high‐yield preparation of Li2CN2 as the activated N‐containing species. In this work, we applied Li2CN2 as a novel synthetic synthon for constructing N‐containing organic compounds. A series of reaction models, including a substitution reaction, cycloaddition reaction, and transition metal‐catalyzed coupling reaction, were successfully performed using Li2CN2 under mild conditions. Various valuable cyanamides, carbodiimides, N‐aryl cyanamides and 1,2,4‐triazole derivatives were readily synthesized in moderate to excellent yields. With this method, the 15N‐labeled products, including oxazolidine derivatives with anti‐cancer activity, could also be facilely prepared from 15N2 gas. [ABSTRACT FROM AUTHOR]

Published
2023
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