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Studying large biomolecules as sedimented solutes with solid-state NMR

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Biophysics Reports 2024年第4期10卷 201-212页

作者： Fan Shi Tong Zhang Juan Li Chaowei Shi Shengqi Xiang moe key Lab for Cellular Dynamics School of Life Sciences Division of Life Sciences and Medicine University of Science and Technology of China Hefei National laboratory for Physical Sciences at Microscale University of Science and Technology of China

Sedimentation solid-state NMR is a novel method for sample preparation in solid-state NMR（ssNMR）studies. It involves the sedimentation of soluble macromolecules such as large protein complexes. By utilizing ultra-high centrifugal forces, the molecules in solution are driven into a high-concentrated hydrogel, resulting in a sample suitable for solid-state NMR. This technique has the advantage of avoiding the need for chemical treatment, thus minimizing the loss of sample biological activity. Sediment ssNMR has been successfully applied to a variety of non-crystalline protein solids, significantly expanding the scope of solid-state NMR research. In theory, using this method, any biological macromolecule in solution can be transferred into a sedimented solute appropriate for solid-state NMR analysis. However, specialized equipment and careful handling are essential for effectively collecting and loading the sedimented solids to solid-state NMR rotors. To improve efficiency, we have designed a series of loading tools to achieve the loading process from the solution to the rotor in one step. In this paper, we illustrate the sample preparation process of sediment NMR using the H1.4-NCP167complex, which consists of linker histone H1.4 and nucleosome core particle, as an example.

关键词： Sedimentation NMR Solid-state NMR Ultracentrifugation Magic angle spinning Nucleosome

Enhancing energy storage efficiency in lead-free dielectric ceramics through relaxor and lattice strain engineering

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Journal of Materiomics 2024年第6期10卷 1196-1205页

作者： Xuetian Gong Chao Zhang Dong Su Wenrong Xiao Fangjie Cen Ying Yang Shenglin Jiang Jing Wang Kanghua Li Guangzu Zhang School of Integrated Circuits Engineering Research Center for Functional Ceramics MOE and Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and TechnologyWuhanHubei430074China College of Chemnistry and Materials Science Hebei UniversityBaodingHebei071002China key Lab of Functional Materials for Electronic Information(B) Ministry of EducationWuhanHubei430074China

Dielectric capacitors with high power density and fast charge-discharge speed play an essential role in the development of pulsed power *** increased demands for miniaturization and practicality of pulsed power equipment also necessitate the development of dielectric materials that possess high energy density while maintaining ultrahigh efficiency(η).In particular,ultrahigh efficiency signifies minimal energy loss,which is essential for practical applications but challenging to effectively ***,we demonstrate a strategy of incorporating heterovalent elements into Ba(Zr_(0.1)Ti_(0.9))O_(3),which contributes to achieving relaxor ferroelectric ceramics and reducing lattice strain,thereby improving the comprehensive energy storage ***,optimal energy storage performance is attained in 0.85Ba(Zr_(0.1)Ti_(0.9))O_(3)-0.15Bi(Zn_(2/3)Ta_(1/3))O_(3)(BZT-0.15BiZnTa),with an ultrahighηof 97.37%at 440 kV/cm(an advanced level in the lead-free ceramics)and an excellent recoverable energy storage density(Wrec)of 3.74 J/cm^(3).Notably,the BZT-0.15BiZnTa ceramics also exhibit exceptional temperature stability,maintaining fluctuations in Wrec within∼10%andηconsistently exceeding 90% across the wide temperature range of−55℃ to 160℃,and under a high electric field of 250 kV/*** these features demonstrate that the relaxor and lattice strain engineering strategies have been successful in achieving high-performance lead-free ceramics,paving the way for designing high-efficiency dielectric capacitors with a wide temperature range.

关键词： Energy storage Relaxor ferroelectrics Lead-free ceramics Lattice strain engineering

Non-contact gaseous microplasma electrode as anode for electrodeposition of metal and metal alloy in molten salt

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Chinese Chemical Letters 2024年第4期35卷 166-169页

作者： Junhan Luo Qi Qing Liqin Huang Zhe Wang Shuang Liu Jing Chen Yuexiang Lu Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China The moe key laboratory of Resources and Environmental System Optimization College of Environmental Science and EngineeringNorth China Electric Power UniversityBeijing 102206China Nuclear Research Institute for Future Technology and Policy Seoul National UniversitySeoul 08826Republic of Korea

Microplasma based on glow discharge could act as a non-contact gaseous electrode and has attracted much attention in both fundamental research and application. Herein, with microplasma as the anode,the electrodeposition process of a series of metal and metal alloys in molten salt has been systemically studied. Four metal cations with different valence states, silver(Ag~+), nickel(Ni^(2+)), copper(Cu^(2+)), and iron(Fe^(3+)), could all be reduced on the solid cathode with high current efficiency and the corresponding metal products were of high purity. The electrodeposition of aluminum-lanthanum(Al-Ln) alloy on the aluminum cathode was also successfully carried out with microplasma as the anode, and the same alloy was obtained by using the conventional anode electrode. These results indicated that microplasma anode based on non-contact direct-current(DC) glow discharge is a promising electrode to be applied in molten salt electrolysis.

关键词： Microplasma Anode Molten salt Electrodeposition Al-Ln alloy

Anti-aging performance improvement and enhanced combustion efficiency of boron via the coating of PDA

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Defence Technology（防务技术） 2024年第3期33卷 399-410页

作者： Shuai Ma Qinghai Shu Mengyang Zhang Hongyu Huang Yansong Shi Xijuan Lv Shuai Zhao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China key Lab of Advanced Optoelectronic Quantum Architecture and Measurement(moe) Beijing Key Lab of Nanophotonics&Ultrafine Optoelectronic SystemsSchool of PhysicsBeijing Institute of TechnologyBeijing100081China Tangshan Research Institute of Beijing Institute of Technology Tangshan063000HebeiChina

Boron is an ambitious fuel in energetic materials since its high heat release values,but its application is prohibited by low combustion efficiency and oxidization during *** polydopamine(PDA)was introduced into boron particles,investigating the impact of PDA content on the energetic behavior of *** results indicated that the PDA coating formed a fishing net structure on the surface of boron *** heat release results showed that the combustion calorific value of B@PDA was higher than that of the raw ***,the actual combustion heat of boron powder in B@10%PDA increased by 38.08%.Meanwhile,the DSC peak temperature decreased by 100.65℃under similar oxidation rate compared to raw ***,the B@PDA@AP and B@AP composites were prepared,and their combustion properties were *** was demonstrated that B@10%PDA@AP exhibited superior performance in terms of peak pressure and burning time,*** peak pressure is 12.43 kPa more than B@AP and burning time is 2.22 times higher than B@***,the coating of PDA effectively inhibits the oxidization of boron during storage and enhances the energetic behavior of boron and corresponding composites.

关键词： Boron particles Polydopamine Anti-aging performance improvement Heat release

Tool wear criterion,tool life,and surface roughness during high-speed end milling Ti-6Al-4V alloy

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第8期11卷 587-595页

作者： Song ZHANG Jian-feng LI moe Key Laboratory of High Efficiency and Clean Mechanical Manufacture School of Mechanical Engineering Shandong University Jinan 250061 China

The objective of the present research is to investigate the relationship among tool wear, surface topography, and surface roughness when high-speed end milling Ti-6Al-4V alloy, and also to define an optimal flank wear criterion for the cutting tool to integrate tool life and the surface roughness requirements of the finish milling process. An annealed Ti-6Al-4V alloy was selected as the workpiece material, undergoing end milling with uncoated carbide inserts. The flank wear of the insert was observed and measured with the toolmaker's microscope. To examine machined surfaces, 3D surface topography was provided by the white light interferometer, and the arithmetical mean roughness (Ra) was calculated with the WYKO Vision32 software. The flank wear increases with cutting time, and the maximal flank wear is set as the flank wear criterion. As the cutting process progresses, tool wear is the predominant factor affecting the variation of surface roughness. According to the plots for the tool wear propagation and surface roughness variation, an optimal flank wear criterion can be defined which integrates the tool life and the surface roughness requirements for the finish milling process.

关键词： Tool wear Surface topography Surface roughness Optimal flank wear criterion

Research on FRP bolt-end failure mechanism

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mining Science and Technology 2009年第4期19卷 522-525页

作者： LI Ying-ming MA Nian-jie YANG Ke SHI Jian-jun School of Energy and safety Anhui University of Science and Technology Huainan Anhui 232001 China moe key laboratory for coalmine safety and high efficiency mining Anhui University of Science and Technology Huainan Anhui 232001 China School of Resources and safety China University of Mining and Technology Beijing 100083 China School of safety Engineering North China University of Science and Technology Beijing 101601 China

Given the fact that FRP bolts for roadway support are often under a certain amount of eccentric load,we studied the problems of failure of FRP bolt-ends using mechanical analysis,numerical simulation and a laboratory experiment to reveal the FRP bolt-end failure *** results show that bolt-end stress increases rapidly,making the maximum stress under an eccentric load to be 5 to 7 times greater than that under a normal load,resulting first in the formation of some fractures at the bolt-end,which then spreads to the entire cross-section of the bolt.

关键词： FRP bolt bolt-end eccentric load failure mechanism

The Potential Game-Changer:A Concept-to-Proof Study on D:A Heterojunction-Free Organic Photovoltaics

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Chinese Journal of Chemistry 2024年第3期42卷 252-258页

作者： Lijian Zuo Sae Byeok Jo Xueliang Shi Francis Lin Alex Jen State key laboratory of Silicon and Advanced Semiconductor Materials MOE Key Laboratory of Macromolecular Synthesis and FunctionalizationDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhouZhejiang310058 China Department of Materials Science and Engineering University of WashingtonSeattleWAUSA School of Chemical Engineering Sungkyunkwan University (SKKU)Suwon16419 Republic of Korea School of Chemistry and Molecular Engineering East China Normal UniversityShanghai200062 China Department of Materials Science and Engineering City University of Hong KongKowloonHong KongChina Department of Chemistry City University of Hong KongKowloonHong KongChina Hong Kong Institute for Clean Energy Hong KongChina

Since 1986,the donor-acceptor (D:A) heterojunction has been regarded a necessity for high-efficiency organic photovoltaics (OPVs),due to its unique advantage in compensating the intrinsic limitations of organic semiconductors,such as high exciton binding energy and poor ambipolar charge mobility. While this adversely causes tremendous non-radiative charge recombination and instability issues,which currently become the most critical limits for commercialization of OPVs. Here,we present a concept-to-proof study on the potential of D:A heterojunction free OPV by taking advantage of recent progress of non-fullerene acceptors. First,we demonstrate that the “free carriers” can be spontaneously generated upon illumination in an NFA,i.e.,the 6TIC-4F single layer. Second,the 6TIC-4F layer also exhibits good ambipolar charge transporting property. These exceptional characteristics distinguish it from the traditional organic semiconductors,and relieve it from the reliance of D:A heterojunction to independently work as active layer. As a result,the subsequent OPV by simply sandwiching the 6TIC-4F layer between the cathode and anode yields a considerably high power conversion efficiency ~1%. Moreover,we find the D:A heterojunction free device exhibits two order of magnitude higher electroluminescence quantum efficiency and significantly reduced VOC loss by 0.16 eV compared to those of the D:A BHJ structure,validating its promise for higher efficiency in the future. Therefore,our work demonstrates the possibility of using D:A heterojunction-free device structure for high performance,that can potentially become the next game changer of OPV.

关键词： Organic solar cells Spontaneous charge generation Ambipolar charge transport Charge recombination Perovskite-like organic semiconductor Schottky-junction structure Single component

Adaptive Change Detection for Long-Term Machinery Monitoring Using Incremental Sliding-Window

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Chinese Journal of Mechanical Engineering 2017年第6期30卷 1338-1346页

作者： Teng Wang Guo-Liang Lu Jie Liu Peng Yan key laboratory of high-efficiency and Clean Mechanical Manufacture of moe School of Mechanical EngineeringShandong University Department of Mechanical and Aerospace Engineering Carleton University

Detection of structural changes from an opera- tional process is a major goal in machine condition moni- toring. Existing methods for this purpose are mainly based on retrospective analysis, resulting in a large detection delay that limits their usages in real applications. This paper presents a new adaptive real-time change detection algorithm, an extension of the recent research by combin- ing with an incremental sliding-window strategy, to handle the multi-change detection in long-term monitoring of machine operations. In particular, in the framework, Hil- bert space embedding of distribution is used to map the original data into the Re-producing Kernel Hilbert Space （RK_HS） for change detection; then, a new adaptive threshold strategy can be developed when making change decision, in which a global factor （used to control the coarse-to-fine level of detection） is introduced to replace the fixed value of threshold. Through experiments on a range of real testing data which was collected from an experimental rotating machinery system, the excellent detection performances of the algorithm for engineering applications were demonstrated. Compared with state-of- the-art methods, the proposed algorithm can be more suitable for long-term machinery condition monitoring without any manual re-calibration, thus is promising in modern industries.

关键词： Machine monitoring Change detection Long-term monitoring Adaptive threshold

Analysis and control of hydraulic support stability in fully-mechanized longwall face to the dip with great mining height

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Journal of Coal Science & Engineering(China) 2008年第3期14卷 399-402页

作者：华心祝王家臣 The moe key laboratory of Coaimine safety and high efficiency mining Anhui University of Science and TechnologyHuainan 232001China School of Resource and safety Engineering China University of Mining and Technology (Beijing)Beijing 100083China

The working condition of the hydraulic support in working face can be divided into three kinds of situations in the following： roof fall and col,lapse with cavity, advancing support and supporting. Took single support with four-pole in Iongwall face to the dip as research object, control method was studied to avoid support instability in three situations mentioned above. Based on these researches, the major factors of influencing on support stability and its controlling measures were put forward. According to specific conditions of working face 1215（3）, which is fully-mechanized and Iongwall face to the dip with great mining height in Zhangji Coal Mine, Huainan mining Group, the effective measures was taken to control supports stability..

关键词： longwall face to the dip fully-mechanized working face with great mining height supports stability control