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Better Choice:linear Long Chains Rather than Branched Ones to Improve Mechanical Performance of Polyethylene through Generating Shish-Kebabs

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Chinese Journal of Polymer Science 2020年第7期38卷 715-729,I0006页

作者： Lu-Feng Deng Xi-Xi Zhang Dong Zhou Jian-Hua Tang jun Lei jun-fang li Zhong-Ming li College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China College of Chemical Engineering Sichuan UniversityChengdu 610065China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

We utilized two structurally different long chains(linear and branched ultra-high molecular weight polyethylene)to reveal the dependence of flow-induced crystallization on long chain architecture,and prepared two bi-disperse systems of 98 wt%short chain and 2 wt%long chain.A flow field was applied to the bi-disperse polyethylene melt by a modified injection-molding machine,known as oscillation shear injection molding(OSIM).For the first time,the structural influence of long chains on flow-induced shish-kebab formation was systematically *** the intermediate layer of OSIM samples,the branched long chains were better than the linear long chains at inducing shish-kebab formation,agreeing with the reported literatures,because the branches can maintain their oriented conformations *** unexpectedly,the reverse is the case for the core layer of OSIM samples,where the shear flow was much weaker than the intermediate *** understand the unexpected phenomenon,the lifetime of shishes induced by different long chains was *** demonstrated that the linear-induced shishes possessed higher thermal stability than the branched-induced ones so that the linear-induced shishes could survive in the core layer of OSIM ***,unlike other methods for flow-induced crystallization,OSIM could create samples for measuring mechanical properties,and thus offer the chance to reveal the relationship between structure and *** mechanical results demonstrated that both long chains remarkably enhanced the mechanical properties because of the significant promoting effect of long chains and intense flow fields on shish-kebab ***,the linear long chains induced more stable and flawless shishes with higher tensile strength and modulus(80.4 and 1613.5 Mpa,respectively)than the branched ones(74.4 and 1489.3 Mpa).Our research not only helps elucidate the mechanism of shish-kebab formation but also provides a better choice to reinforce

关键词： Polyethylene Crystallization Shear-induced Long chain Short chain

Determination of Chlorine in Human Urine by Detecting Backscattering Signals with a New Optical Assembly

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Chinese Chemical Letters 2006年第5期17卷 679-682页

作者： Ke jun TAN Yuan fang li Cheng Zhi HUANG Xue lian liU College of Chemistry and Chemical Engineering Southwest University Chongqing 400715

Detection of backscattering signals （BSS） generally suffers from the interference of reflected light, and it is hard to apply these signals for analytical purpose. Herein we provided an optical assembly, which effectively eliminated the interference of reflected light so that the scattering signals of analyte could be measured distinctly. With this assembly, chlorine in human urine could be detected with the limit of detection （LOD） of 2.0 ng/mL by measuring the enhanced BSS signals produced between the interactions of chlorine with silver nitrate.

关键词： Chlorine urine backscattering signals.

Aluminum（Ⅲ）ion sensor based on the sensitive membrane containing ***2O3 powders

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Journal of Chemistry and Chemical Engineering 2008年第4期2卷 47-52页

作者： MA Chuan-li HE li-jun, TIAN li-fang WANG Chun-ming （School of Chemistry. and Chemical Engineering Lanzhou University Lanzhou 730000 China

An AI^3＋ sensor based on the membrane of acetyl cellulose containing nano γ-Al2O3 crystals was studied. In the buffer solution of 0.5 mol/L CH3COOH-CH3COONa （pH=5.0）, the sensor responds to AI^3＋ in a linear range from 1.00×10^-5 to 1.00x10-^2 mol/L. A near-Nernstian response was obtained and the regression equation was E （mv） = -161.4-26.54 Ig [AI^3＋] with a detection limit of 7.90x10^-6 mol/L. More than 14 different ions as the considered interferences were tested and the relevant selectivity coefficients were determined using the separate solution method （SSM）. The sensor possesses many advantages including short conditioning time, fast response, and, especially, very good selectivity over a wide variety of other co-existing ions. The sample analysis on the aluminium migration amount from aluminium utensils to the solution was determined by this sensor. The analytical results were agreed with that of inductively coupled plasma-atomic emission spectroscopy（ICP-RES）.

关键词： sensor aluminum (Ⅲ) acetyl cellulose membrane nano γ-Al2O3

Fiber Bragg Grating Sensor Array System Based on Digital Phase Generated Carrier Demodulation and Reference Compensation Method

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Journal of Electronic Science and Technology of China 2008年第4期6卷 389-392页

作者： jun He fang li Hao Xiao Yu-liang liu Optoelectronic System Laboratory Institute ofSemiconductors Chinese Academy of Sciences Beijing 100083 China

A novel fiber Bragg grating （FBG） sensor array system based on digital phase generated carrier （PGC） demodulation and reference compensation method is proposed and set up. Experimental results confirm that the digital PGC demodulation can be used for wavelength-division-multiplexed FBG sensor array and the reference compensation method can reduce the environmental interference by approximately 40 dB in the frequency range from 20 Hz to 2 kHz. The minimum detectable wavelength-shift of the sensor system is 1 × 10^-3 pm/Hz^1/2.

关键词： Fiber Bragg grating (FBG) sensor,phase generated carrier (PGC) reference compensation method wavelength division multiplexing.

Targeting cholesterol trafficking to mitigate axonal degeneration in hereditary spastic paraplegia

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Neural Regeneration Research 2025年第5期20卷 1397-1398页

作者： Zhenyu Chen Xue-jun li Department of Biomedical Sciences University of Illinois College of Medicine RockfordRockfordILUSA Department of Bioengineering University of Illinois at ChicagoChicagoILUSA

Axonal degeneration underlies many debilitating diseases including hereditary spastic paraplegia(HSP),a genetically and clinically diverse group of disorders characterized by spasticity and weakness of the lower *** is one significant cause of chronic neurodisability due to the lack of effective treatments and a wide range of onset ages from early childhood to 70 years.

关键词： degeneration diseases hereditary

Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

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Science China Chemistry 2025年第1期68卷 233-240页

作者： Peipei liu Yantong li Meng-Xiang Wu Hao Kang Xiao-li Zhao lin Xu linlin liu Xiaodong li junfeng fang Zhiwei fang Ya Cheng Hai-Bo Yang Huakang Yu Xueliang Shi State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology Institute of Polymer Optoelectronic Materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

关键词： double carbohelicene optical resolution organic laser isomerization X-ray diffraction

Deciphering the role of mtH2O2 in hepatic ischemia-reperfusion injury mechanisms with low-background super-resolution fluorogenic probe

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Science China Chemistry 2025年第1期68卷 297-307页

作者： Bin fang limin Wang Haoqin li Jiaxin Zhang Yang Ding Pan Pan li Bo Peng Hua Bai lin li Frontiers Science Center for Flexible Electronics Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials &Engineering Northwestern Polytechnical University Institute of Flexible Electronics (IFE Future Technologies) Xiamen University

Hepatic ischemia-reperfusion injury（HIRI） is characterized by mitochondrial dysfunction and oxidative stress. Monitoring mitochondrial hydrogen peroxide（mtH2O2） levels in real-time through super-resolution imaging is crucial for elucidating its distribution in live cells and its mechanism of action during HIRI. However, low-background fluorogenic probes have been overlooked in the context of super-resolution imaging. In this study, we developed a low-background fluorogenic probe（MitoWG） with the potential for super-resolution morphology-correlated mitochondrial identification to track the fluctuates of mtH2O2in HIRI. Activation of the desirable fluorescence properties of the probe by mtH2O2was confirmed using structural illumination microscopy（SIM）, enabling high-quality mitochondrial imaging with exceptional specificity and *** in mtH2O2levels were successfully observed in both cellular and rat models of HIRI. Furthermore, we associated the decline in mitochondrial redox homeostasis with accelerated mtH2O2production during HIRI, which triggered mitophagy deficiency and led to cell death. In conclusion, Mito-WG possesses excellent photophysical and low-background properties for SIM imaging, making it a promising tool for mtH2O2tracking in HIRI research and clinical diagnosis.

关键词： hepatic ischemia-reperfusion injury low-background mtH2O2-activatable super-resolution imaging fluorogenic probe

Emerging progress: photochemical transformation of nitroso compounds

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Science China Chemistry 2025年第1期68卷 118-133页

作者： Ze-Le Chen Qiang-Qiang li Armido Studer jun Xuan Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials School of Chemistry & Chemical Engineering Anhui University Organisch-Chemisches Institut Universitat Münster

Nitroso compounds have emerged as highly valuable reaction partners or reagents in organic synthesis due to their rich *** versatile profile of these compounds allows them to function as electrophiles, nucleophiles, diradicals, and radical acceptors in diverse transformations. In recent years, notable progress has been made in harnessing photochemical reactions with nitroso compounds to prepare N,O-containing structures using mild and eco-friendly conditions. Various nitroso compounds like nitrosoarenes, acyloxy nitroso compounds, N-nitrosoamines and nitrites have received significant attention for their ability to introduce NO moieties into complex molecules that are otherwise difficult to access. In this review, we provide an overview of the recent advancements in the visible light-induced conversion of nitroso compounds, with particular emphasis on their role as bifunctional reagents and acceptors of radicals, carbenes and nitrenes.

关键词： nitroso compounds photochemistry radical reaction carbene transformation nitrosoarenes

Turbulent Agglomeration of Microparticles in a Cylinder Wake Flow Using LES-DEM:Focusing on the Effect of the Reynolds Number

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Journal of Thermal Science 2025年第1期34卷 34-49页

作者： WANG Shuang MU lin li Xue XIE jun DONG Ming School of Energy and Power Engineering Dalian University of Technology School of Optical Information and Energy Engineering Wuhan Institute of Technology School of Energy and Environment Shenyang Aerospace University

Turbulent agglomeration is viewed as a promising technology for enhancing fine particle removal *** better understand particle transport,agglomeration behaviors,and fluid-particle interactions,we numerically explored these phenomena under cylindrical vortex wake influence using a coupled large eddy simulation and discrete element method（LES-DEM） *** validity of the LES approach was verified by comparison with available direct numerical simulation（DNS） *** adopted the Johnson-Kendall-Roberts（JKR） contact model for particle-particle *** particle dispersion and agglomeration characteristics of particles with different diameters（dp=2-20 μm） in the laminar and transition of shear layer（TrSL） flow regimes were *** particles were concentrated at the vortex centers,while larger particles accumulated around the *** agglomeration efficiency exhibited an M-shaped profile spanwise（y-direction）.With increasing Reynolds number,the agglomeration efficiency and turbulence intensity *** particle agglomeration efficiency peaks at a certain Reynolds ***,at higher Reynolds numbers,reducing the residence time of particles in the flow field decreases the agglomeration efficiency.

关键词： discrete element method large eddy simulation microparticle particle agglomeration