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A novel CHS/ALG bi-layer composite membrane with sustained antimicrobial efficacy used as wound dressing

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Chinese Chemical Letters 2010年第8期21卷 1011-1014页

作者： Yang Dong Hong Zhuo liu Lu Xu Gang li Zi Ning Ma Fei Han Hui Min Yao Yah Hui Sun san ming li School of Pharmaceutics Shenyang Pharmaceutical University Shenyang 110016 China China Criminal Police University Shenyang 110035 China

A membrane composed of an alginate（ALG） layer and a chitosan（CHS） layer with sustained antimicrobial efficacy was *** HC1（CIP） was incorporated into the ALG *** feature of the composite membrane was analyzed by scanning electron microscopy（SEM）.Water uptake capacity,in vitro drug release,and in vitro antimicrobial activity were *** composite membrane exhibited perfect binding characteristic between the two *** water uptake capacity of all the membranes was above 800%.The CIP could release from the composite membranes for 48 *** membrane could control the bacterial growth *** results suggested that this CHS/ALG composite membrane incorporated with CIP had the potential for wound dressing application.

关键词： Chitosan Alginate Composite membrane Ciprofloxacin HCl Sustained release Antimicrobial efficacy

A multi-objective optimization based on machine learning for dimension precision of wax pattern in turbine blade manufacturing

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Advances in Manufacturing 2024年第3期12卷 428-446页

作者： Jing Dai Song-Zhe Xu Chao-Yue Chen Tao Hu san-san Shuai Wei-Dong Xuan Jiang Wang Zhong-ming Ren State Key Laboratory of Advanced Special Steels School of Materials Science and EngineeringShanghai UniversityShanghai200444People’s Republic of China

Wax pattern fabrication in the investment casting of hollow turbine blades directly determines the dimension accuracy of subsequent casting,and therefore significantly affects the quality of final *** this work,we develop a machine learning-based multi-objective optimization framework for improving dimension accuracy of wax pattern by optimizing its process *** consider two optimization objectives on the dimension of wax pattern,i.e.,the surface warpage and core *** active learning of Bayesian optimization is employed in data sampling to determine process parameters,and a validated numerical model of injection molding is used to compute objective results of dimension under varied process *** collected dataset is then leveraged to train different machine learning models,and it turns out that the Gaussian process regression model performs best in prediction accuracy,which is then used as the surrogate model in the optimization framework.A genetic algorithm is employed to produce a non-dominated Pareto front using the surrogate model in searching,followed by an entropy weight method to select the most optimal solution from the Pareto *** optimized set of process parameters is then compared to empirical parameters obtained from previous trial-and-error experiments,and it turns out that the maximum and average warpage results of the optimized solution decrease 26.0%and 20.2%,and the maximum and average errors of wall thickness compared to standard part decrease from 0.22 mm and 0.0517 mm using empirical parameters to 0.10 mm and 0.0356 mm using optimized parameters,*** framework is demonstrated capable of addressing the challenge of dimension control arising in the wax pattern production,and it can be reliably deployed in varied types of turbine blades to significantly reduce the manufacturing cost of turbine blades.

关键词： Hollow turbine blade Wax pattern fabrication Dimension control Multi-objective optimization Machine learning Numerical simulation

Design of weak current measurement system and research on temperature impact

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Nuclear Science and Techniques 2024年第4期35卷 46-56页

作者： Chu-Xiang Zhao san-Gang li Rong-Rong Su li Yang ming-Zhe liu Qing-Yue Xue Shan liao Zhi Zhou Qing-Shan Tan Xian-Guo Tuo Yi Cheng College of Nuclear Technology and Automation Engineering Chengdu University of Technology1#DongsanluErxianqiaoChengdu 610059China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province Chengdu University of Technology1#DongsanluErxianqiaoChengdu 610059China University of Science and Technology of China Hefei 230026China School of Physics and Electronic Engineering Sichuan University of Science and EngineeringZigong 643000China

A dedicated weak current measurement system was designed to measure the weak currents generated by the neutron ionization *** system incorporates a second-order low-pass filter circuit and the Kalman filtering algorithm to effectively filter out noise and minimize interference in the measurement *** conducted under normal temperature conditions has demonstrated the system's high precision ***,it was observed that temperature variations can affect the measurement *** were collected across temperatures ranging from -20 to 70℃,and a temperature correction model was established through linear regression fitting to address this *** feasibility of the temperature correction model was confirmed at temperatures of -5 and 40℃,where relative errors remained below 0.1% after applying the temperature *** research indicates that the designed measurement system exhibits excellent temperature adaptability and high precision,making it particularly suitable for measuring weak currents.

关键词： Weak current measurement system Neutron ionization chamber Kalman filter algorithm Temperature correction model

Optimal Timing of Business Conversion for Solvency Improvement

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 744-757页

作者： Peng li ming ZHOU School of Finance Nanjing University of Finance and EconomicsNanjing 210023China Center for Applied Statistics and School of Statistics Renmin University of ChinaBeijing 100872China

In this paper,we study the optimal timing to convert the risk of business for an insurance company in order to improve its *** cash flow of company evolves according to a jump-diffusion *** conversion option offers the company an opportunity to transfer the jump risk business *** exchange for this option,the company needs to pay both fixed and proportional transaction *** proportional cost can also be seen as the profit loading of the jump risk *** formulated this problem as an optimal stopping *** solving this stopping problem,we find that the optimal timing of business conversion mainly depends on the profit loading of the jump risk business.A larger profit loading would make the conversion option *** fixed cost,however,only delays the optimal timing of business *** the end,numerical results are provided to illustrate the impacts of transaction costs and environmental parameters to the optimal strategies.

关键词： optimal stopping jump-diffusion process conversion option

Investigation on UV-curing Reprocessable Thermosets Bearing Hindered Urea Bonds and Their Composites with Modified Zinc Oxide Nanoparticles

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Chinese Journal of Polymer Science 2024年第6期42卷 751-765页

作者： Jun-Hao Zhou li-ming Tang Key Laboratory of Advanced Materials of Ministry of Education of China Department of Chemical EngineeringTsinghua UniversityBeijing100084China

In this study,a series of hindered urea bond(HUB)containing polyurethane-urea methacrylate prepolymers and a none HUB containing polyurethane methacrylate prepolymer were prepared using isobornyl methacrylate as the reactive diluent via one-pot *** prepolymers were characterized fully by various ***,their thermosets were fabricated via UV curing in presence of a photo initiator,and their mechanical property and thermal behavior were investigated and *** from the none HUB containing thermoset,the HUB containing thermosets(defined as PUT)could be recycled and reprocessed by hot press under relatively mild conditions with high recovery ratio of mechanical ***,zinc oxide(ZnO)nanoparticles were modified with 3-(trimethoxysilyl)propyl methacrylate and the modified ZnO(defined as ZnO-TPM)was dispersed and polymerized into PUT matrix to prepare their *** influence of ZnO-TPM on the mechanical performance of the composites was evaluated,which indicated that the Young’s modulus and tensile strength increased gradually to the maximum values at ZnO-TPM content of 1 wt%and then *** composites also displayed good reprocessability with improved recovery ratio compared to the pure PUT *** addition,the composite materials exhibited strong UV absorption capacity,implying their potential application in the circumstance where UV-shielding was required.

关键词： Polyurethane-urea methacrylate Hindered urea bond ZnO nanoparticles Reprocessing UV curing

Scaling laws governing the elastic properties of 3D graphenes

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Science China(Technological Sciences) 2024年第6期67卷 1748-1756页

作者： li ming LU Guo YU HaoDong li MengLei ZHENG FaWei Centre for Quantum Physics Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement(MOE)School of PhysicsBeijing Institute of TechnologyBeijing100081China Beijing Key Lab of Nanophotonics&Ultrafine Optoelectronic Systems School of PhysicsBeijing Institute of TechnologyBeijing100081China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing100088China Department of Physics Capital Normal UniversityBeijing100048China

In this study,we comprehensively investigated the scaling law for elastic properties of three-dimensional honeycomb-like graphenes(3D graphenes)using hybrid neural network potential-based molecular dynamics simulations and theoretical *** elastic constants were obtained as functions of honeycomb hole size,denoted by the graphene wall length *** five independent elastic constants in the large-L limit are proportional to L^(-1).The associated coefficients are combinations of elastic constants of two-dimensional ***-order terms including L^(-2)and L^(-3)emerge for finite L *** have three origins,the distorted areas close to the joint lines of 3D graphenes,the variation in solid angles between graphene plates,and the bending distortion of graphene ***,the chirality becomes essential with decreasing L because the joint line structures are different between the armchair and zigzag-type 3D *** findings provide insights into the elastic properties of graphene-based superstructures and can be used for further studies on graphene-based materials.

关键词： scaling law neural network elastic properties 3D graphene

Slip distribution inversion of seismic sub-fault dip iteration using gradient based optimizer algorithm

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Geodesy and Geodynamics 2024年第2期15卷 114-121页

作者： Leyang Wang Han li ming Pang Key Laboratory of Mine Environmental Monitoring and Improving Around Poyang Lake of Ministry of Natural Resources East China University of TechnologyNanchang 330013China School of Surveying and Geoinformation Engineering East China University of TechnologyNanchang 330013China College of Resources and Environment Shandong Agricultural UniversityTaian 271018China

This paper considers setting different dips for different sub-faults to fit the actual rupture situation based on the fault rupture of the 2013 Lushan M_(S)7.0 ***,combined with the coseismic GNSS data of the Lushan earthquake,the source parameters and sliding distribution of the Lushan earthquake fault are ***,we use the gradient based optimizer(GBO)in nonlinear inversion to obtain the source parameters of this seismic *** inversion results indicate that the strike of the fault is 206.52°,the dip is 44.10°,the length is 21.92 km,and the depth is 12.79 *** refine the sliding distribution of the seismic fault,the seismic fault is divided into 3×3 ***,we fix the central sub-fault dip of 44.10°;the dip of other sub-faults is obtained by *** that,the model is further divided into a fault layer model composed of 23×19 sub fault slices,and using the Matlab fitting function is used to fit the dip of the 23×19 sub ***,the Lushan seismic fault plane is established as a shovel structure with steep upper and gentle lower,steep south and gentle *** slip distribution inversion results indicate that the depth of the slip peak is 13 km,the corresponding maximum slip momentum is 0.67 m,the seismic moment is 1.10×10^(19)N·m and the corresponding moment magnitude is *** results above are consistent with the research results of seismology.

关键词： Gradient basedoptimizer(GBO) Lushan earthquake Non-planefault model Slid distribution

Ti_(3)C_(2)T_(x)/SnO_(2)P–N heterostructure construction boosts room-temperature detecting formaldehyde

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Rare Metals 2024年第1期43卷 267-279页

作者： Yue Zhang ming-Yue Wang Xiao-Guang san Yan-Bai Shen Guo-Sheng Wang Lei Zhang Dan Meng College of Chemical Engineering Shenyang University of Chemical TechnologyShenyang 110142China Institute for Superconducting and Electronic Materials(ISEM) Australian Institute for Innovative Materials(AIIM)University ofWollongongWollongongNSW2500Australia College of Resources and Civil Engineering Northeastern UniversityShenyang 110819China

Formaldehyde is a common atmospheric pollutant produced in industrial production and daily ***,the traditional semiconductor formaldehyde gas sensor cannot work at room temperature,which limits its practical ***,developing high-performance gas sensors for rapidly and accurately detecting formaldehyde at room temperature is an important *** this study,Ti_(3)C_(2)Tx/SnO_(2)heterostructures were constructed,which could selectively detect formaldehyde at room temperature with a response value of 29.16%(10×10^(-6)).In addition,the sensor shows a remarkable theoretical detection limit of 5.09×10^(-9)and good longterm *** functional theory(DFT)simulations reveal that SnO_(2)nano spheres provide the majority of adsorption sites that strongly interact with ***,Ti_(3)C_(2)T_(x)acting as a conductive layer facilitates the transfer of charge carriers so that they show a sensing response to formaldehyde at room ***,the formation of p-n heterostructures between SnO_(2)and Ti_(3)C_(2)T_(x)boosts the Schottky barrier at the interface,which is the critical factor in enhancing the sensing properties by turning the Schottky barrier upon introducing formaldehyde *** perspective is expected to provide instructive guidance for utilizing MXene/metal oxide nanocomposites to improve the gas sensing performance at room temperature.

关键词： Ti_(3)C_(2)T_(x)/SnO_(2)nanocomposites p-n heterostructures Formaldehyde sensing Room temperature DFT calculations

Modifying Lyapunov exponent of chaotic map by self-cascading

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Science China(Technological Sciences) 2024年第7期67卷 2203-2214页

作者： YI ChenLong li ChunBiao li YongXin XIA ming HUA ZhongYun School of Electronic and Information Engineering Nanjing University of Information Science&TechnologyNanjing 210044China School of Artificial Intelligence Nanjing University of Information Science&TechnologyNanjing 210044China School of Computer Science and Technology Harbin Institute of Technology Shenzhen Graduate SchoolShenzhen 518055China

The self-cascade(SC) method is an effective technique for chaos enhancement and complexity increasing in chaos ***, the controllable self-cascade(CSC) method allows for more accurate control of Lyapunov exponents of the discrete map. In this work, the SC and CSC systems of the original map are derived, which enhance the chaotic performance while preserving the fundamental dynamical characteristics of the original map. Higher Lyapunov exponent of chaotic sequences corresponding to higher frequency are obtained in SC and CSC systems. Meanwhile, the Lyapunov exponent could be linearly controlled with greater flexibility in the CSC system. The verification of the numerical simulation and theoretical analysis is carried out based on the platform of CH32.

关键词： self-cascade controllable self-cascade chaos enhancement chaos control