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Modulation of Conformational Transition of Polypeptides under Slightly Acidic Environment

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Chinese Journal of Chemistry 2022年第24期40卷 2981-2987,I0002页

作者： Jie Li Jiajie Zhang Qi Long Weisheng Guo Menghua Xiong Guangzhou First People's Hospital School of Biomedical Sciences and EngineeringSouth China University of TechnologyGuangzhou International CampusGuangzhouGuangdong511442 China National Engineering Research Center for Tissue Restoration and Reconstruction South China University of TechnologyGuangzhouGuangdong510006 China Translational Medicine Center Key Laboratory of Molecular TargetClinical PharmacologySchool of Pharmaceutical SciencesThe Second Affiliated HospitalGuangzhou Medical UniversityGuangzhouGuangdong510260 China Key Laboratory of Biomedical Engineering of Guangdong Province and Innovation Center for Tissue Restoration and ReconstructionSouth China University of TechnologyGuangzhouGuangdong510006 China Key Laboratory of Biomedical Materials and Engineering of the Ministry of Education South China University of TechnologyGuangzhouGuangdong510006 China

Controlling the conformational transition of polypeptides under slightly acidic environment is challenging.Herein,we report a class of pH-responsive helix-to-coil conformationally transitionable polypeptides(pCTPs)by simply conjugating tertiary amine groups(TAs)to polylysine.Their conformation is highly dependent on the charge state of TAs,showing a helical structure when most TAs are deprotonated and a non-helical structure when majority of TAs are protonated.The conformational transition pH can be modulated by tuning the hydrophobicity of TAs and the incorporation of hydrophobic monomers at a pH range of 7.2 to 6.0.Such pCTP showed a vesicle-to-micelle transition when their conformation transformed from helix to coil,facilitating controlled drug release.Our study provided an approach to control the conformational transition of polypeptides under slightly acidic condition.

关键词： Peptides Conformational transition Helical structures pH responsiveness Drug delivery

Feature selection of BOF steelmaking process data by using an improved grey wolf optimizer

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Journal of Iron and Steel Research(International) 2022年第8期29卷 1205-1223页

作者： Zong-xin Chen Hui Liu long qi Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming 650500YunnanChina Yunnan Key Laboratory of Artificial Intelligence Kunming University of Science and TechnologyKunming 650500YunnanChina

Basic oxygen furnace(BOF)steelmaking end-point control using soft measurement models has essential value for economy and environment.However,the high-dimensional and redundant data of the BOF collected by the sensors will hinder the performance of models.The traditional feature selection results based on meta-heuristic algorithms cannot meet the stability of actual industrial applications.In order to eliminate the negative impact of feature selection application in the BOF steelmaking,an improved grey wolf optimizer(IGWO)for feature selection was proposed,and it was applied to the BOF data set.Firstly,the proposed algorithm preset the size of the feature subset based on the new encoding scheme,rather than the traditional uncertain number strategy.Then,opposition-based learning was used to initialize the grey wolf population so that the initial population was closer to the potential optimal solution.In addition,a novel population update method retained the features closely related to the best three grey wolves and probabilistically updated irrelevant features through measurement or random methods.These methods were used to search feature subsets to maximize search capability and stability of algorithm on BOF steelmaking data.Finally,the proposed algorithm was compared with other feature selection algorithms on the BOF data sets.The results show that the proposed IGWO can stably select the feature subsets that are conductive to the end-point regression accuracy control of BOF temperature and carbon content,which can improve the performance of the BOF steelmaking.

关键词： Basic oxygen furnace Feature selection Grey wolf optimization Regression Opposition-based learning

Recent advances in the regulation mechanism of SOX10

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Journal of Otology 2022年第4期17卷 247-252页

作者： Jingcui qi long Ma Weiwei Guo Department of Otorhinolaryngology The First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina PLA Rocket Force Characteristic Medical Center Department of Stomatology China College of Otolaryngology Head and Neck Surgery Chinese PLA General HospitalBeijing 100853China National Clinical Research Center for Otolaryngologic Diseases BeijingChina Key Lab of Hearing Science Ministry of EducationChina Beijing Key Lab of Hearing Impairment for Prevention and Treatment BeijingChina

Neural crest(NC)is the primitive neural structure in embryonic stage,which develops from ectodermal neural plate cells and epithelial cells.When the neural fold forms into neural tube,neural crest also forms a cord like structure above the neural tube and below the ectoderm.Neural crest cells(NCC)have strong migration and proliferation abilities.A number of tissue cells differentiate from neural crest cells,such as melanocytes,central and peripheral neurons,glial cells,craniofacial cells,osteoblasts,chondrocytes and smooth muscle cells.The migration and differentiation of neural crest cells are regulated by a gene network where a variety of genes,transcriptional factors,signal pathways and growth factors are involved.

关键词： neural facial crest

Alternative flexible correction forming of a blade: multipoint correction with surface measurement and deformation simulation

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Advances in Manufacturing 2023年第4期11卷 587-600页

作者： Da-Wei Zhang Wen-long Gao-Zhang qi Zhang Xi’an Key Laboratory of Intelligent Equipment and Control School of Mechanical EngineeringXi’an Jiaotong UniversityXi’an710049People’s Republic of China

Distortion during the forging or machining processes of a blade causes problems in subsequent manufacturing. This paper proposes an alternative multipoint correction method integrated with blade measurement, determination of correcting parameters, and adjustment of the correcting die. An iterative algorithm for determining the correcting parameters is proposed. Measuring equipment combining a laser displacement sensor with multipoint flexible support is manufactured to measure the blade shape. Multipoint correcting equipment with an adaptive lower die and rapid adjustment is manufactured, and software is developed for data analysis and equipment control. The correction experiment for a rough-machined steam-turbine blade indicates that the correcting parameters can be determined after one modification based on numerical simulation, and that a rough blade that meets the allowance for finish machining can be obtained using the determined correction parameters.

关键词： Blade Surface measurement Numerical simulation Multipoint correction

Recent Progress in Donor-Acceptor Type Conjugated Polymers for Organic Field-effect Transistors

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Chinese Journal of Polymer Science 2023年第5期41卷 652-670,I0006页

作者： Yi-Fan Li Yun-long Guo Yun-qi Liu Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic solidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The recent progress in the design and synthesis of high-performance donor-acceptor conjugated polymeric semiconducting materials is reviewed from the perspective of multiscale structures.The multiscale of conjugated polymers is from the primary one-dimensional polymer molecular scale to the secondary polymer-chains interaction scale,and then to the tertiary polymer aggregate scale.This review focuses on the design and synthesis of polymer molecules,proposes new classification rules,and rationally summarizes the design strategies and modulation methods of polymers.We describe the recent progress from these three aspects:(1)the modification ofπ-conjugated backbone,(2)the evolution of the polymerization methods,and(3)the regulation of aggregate-state structure.

关键词： Conjugated polymers Donor-acceptor Organic field-effect transistors Multiscale optimization

Anti-sintering behavior and combustion process of aluminum nano particles coated with PTFE:A molecular dynamics study

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Defence Technology（防务技术） 2023年第6期24卷 46-57页

作者： Jun-peng Liu Hao-rui Zhang qi-long Yan Science and Technology on Combustion Internal Flow and Thermostructure LaboratoryNorthwestern Polytechnical UniversityXi'an 710071China

The characteristic of easy sintering of aluminum nanoparticle(ANP)limits its application in solid propellants.Coating ANP with fluoropolymer could effectively improve its combustion performance.To find out how the coating layer inhibits sintering and promotes complete combustion of particles from an atomic view,a comparative study has been done for bare ANP and PTFE coated ANP by using reactive molecular dynamics simulations.The sintering process is quantified by shrinkage ratio and gyration radius.Our results show that,at the same heating rate and combustion temperatures,bare ANPs are sintered together after the temperature exceeds the melting point of aluminum but the decomposition of PTFE coating layer pushes particles away and increases reaction surface area by producing small Al-F clusters.The sintering of ANPs which are heated in PTFE is alleviated compared with particles heated in oxygen,but particles still sinter together due to the lack of intimate contact between PTFE and alumina surface.The effect of temperature on the combustion of PTFE coated ANPs is also studied from 1000 to3500 K.The number density analysis shows the particles will not be sintered at any temperature.Aluminum fluoride prefers diffusing to the external space and the remained particles are mainly composed of Al,C and O.Fast ignition simulations are performed by adopting micro canonical ensemble.With the expansion of aluminum core and the melting of alumina shell,bare ANPs are sintered into a liquid particle directly.For PTFE coated ANPs,the volatilization of gaseous aluminum fluoride products continually endows particles opposite momentum.

关键词： Aluminum nanoparticle Sintering Combustion Molecular dynamics simulation

Electro-mechanical coupling properties of band gaps in an with periodically attached “spring-mass” resonators

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Applied Mathematics(A Journal of Chinese Universities) 2023年第3期38卷 429-443页

作者： ZHANG Jian qiAN Deng-hui REN long WANG qi School of Naval Architecture&Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China China Nanhu Academy of Electronics and Information Technology Jiaxing 314000China

The model of a locally resonant (LR) epoxy/PZT-4 phononic crystal (PC)nanobeam with “spring-mass” resonators periodically attached to epoxy is proposed. The corresponding band structures are calculated by coupling Euler beam theory, nonlocal piezoelectricity theory and plane wave expansion (PWE) method. Three complete band gaps with the widest total width less than 10GHz can be formed in the proposed nanobeam by comprehensively comparing the band structures of three kinds of LR PC nanobeams with resonators attached or not. Furthermore, influencing rules of the coupling fields between electricity and mechanics,“spring-mass” resonator, nonlocal effect and different geometric parameters on the first three band gaps are discussed and summarized. All the investigations are expected to be applied to realize the active control of vibration in the region of ultrahigh frequency.

关键词： phononic crystal nanobeam electro-mechanical coupling effect nonlocal effect locally resonant mechanism

Precision wire electrochemical machining of thick structures in powder superalloy René88DT using a partially insulated tube electrode

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Advances in Manufacturing 2023年第4期11卷 618-635页

作者： Cheng Tang Zhao Han Zhong-qi Zhou Xiao-long Fang Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology Nanjing University of Aeronautics and AstronauticsNanjing210016People’s Republic of China

Wire electrochemical machining(WECM)is a potential method for manufacturing macrostructures from difficult-to-cut materials,such as turbine slots,with good surface integrity and low costs.In this study,a novel tube electrode with array holes in the front and insulation in the back was applied using WECM to improve the machining precision and efficiency.Additionally,assisted by an immersion electrolyte and axial flushing,the electrolyte-deficient gap was supplemented to achieve the cutting of a very thick workpiece.The simulation results indicated that this method could effectively reduce the machining gap and improve the uniformity of the electric-and flow-field distributions.Experiments verified that when the uninsulated range(machining angle)was reduced from 360°to 90°,the side machining gap was reduced from 462.5µm to 175µm.Finally,using optimized machining parameters,array slits with gaps as small as(175±10)μm were machined on a powder superalloy René88DT sample with a thickness of 10 mm at a feed rate of 16µm/s.The feasibility of fabricating complex profiles using this method was verified using a self-designed servo device.

关键词： Wire electrochemical machining(WECM) Tube electrode Partial insulation Machining angle Electrolyte flushing Surface quality

Effect of Al_(2)O_(3)/SiO_(2) mass ratio and CaO content on viscosity and structure of slag for pyrometallurgical processing of spent automotive catalysts

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Journal of Iron and Steel Research(International) 2024年第3期31卷 608-621页

作者： Zhe Wang qi-long Wei Cheng-bin Shi Zhan-cheng Guo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

The effect of Al_(2)O_(3)/SiO_(2) mass ratio and CaO content on the viscosity and structure of the CaO-Al_(2)O_(3)-SiO_(2)-6MgO-1.5ZrO_(2)-1.5CeO_(2) slag was investigated.The results show that with the increase in Al_(2)O_(3)/SiO_(2) mass ratio,the viscous flow units within the slag gradually change from Si-O-Si to Al-O-Al and Al-O-Si.Furthermore,the substitution of Al_(2)O_(3) for SiO_(2) leads to the transformation of Si-O bonds towards weaker Al-O bonds,which weaken the bond strength of the aluminosilicate networks,thus leading to a decrease in the viscosity of slag.The increase in CaO content effectively promotes the depolymerization of the aluminosilicate networks,resulting in a significant decrease in the viscosity of the slag.The slag with Al_(2)O_(3)/SiO_(2) of 0.7-1.5 and CaO of 30 wt.%shows promise as the reference slag system for the Fe-collection smelting of spent automotive catalysts due to its good comprehensive performance.

关键词： Aluminosilicate slag Al_(2)O_(3)/SiO_(2)mass ratio CaO content Viscosity Slag structure