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Determination of Vitamin B_1 in Pharmaceutical Preparations by Flow-injection Analysis with Biamperometric Detection

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Chemical Research in Chinese Universities 2005年第6期21卷 650-653页

作者： LI Li-jun CHENG Hao ZHAO chuan HU xiao-ge Department of Biological and Chemical Engineering Guangxi University of Technology Liuzhou 545006 P. R. China Institute of Analytical Science Northwest University Xi＇an 710069 P. R. China

A new electrochemical method for the on-line determination of vitamin B1 is presented. Based on dead-stop endpoint biamperometry by using two platinum foil electrodes with an applied potential difference of 150 mV, vitamin B1 can be oxidized by hexacyanoferrate （ Ⅲ ） in a sodium hydroxide medium via a reversible indicating couple Fe（ CN）6^4- /Fe（CN）6^3- The cell current is linear with the concentration of vitamin B1 in the concentration range of 4. 0 × 10^-6-1.0 × 10^ -3 mol/L with a detection limit of 8.0 ×10 ^-7 mol/L（0. 27 μg/mL）. Most familiar excipients, ions and vitamins do not interfere with the determination of vitamin B1. The method displays the advantages of simplicity, high efficiency（ 180 samples/h）, and high selectivity, and is suitable for the determination of vitamin B1 in pharmaceutical preparations.

关键词： Pharmaceutical analysis Biamperometry Vitamin B1 How-injection analysis

Practical tracking of MIMO uncertain stochastic systems driven by colored noises via active disturbance rejection control

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Science China(Information Sciences) 2022年第6期65卷 203-217页

作者： Chunwan LV Zhengyong OUYANG Zehao WU Feiqi deng Mingqing xiao School of Mathematics and Big Data Foshan University Systems Engineering Institute South China University of Technology Department of Mathematics Southern Illinois University

This study addresses the practical tracking problem for a class of multi-input multi-output(MIMO) uncertain stochastic systems driven by colored noises via the active disturbance rejection control approach. The extended state observer is designed to estimate in real time the unmeasurable states and the stochastic total disturbance of each subsystem, including unknown coupling system dynamics between subsystems, colored noises, and uncertainty caused by partly unknown control parameters. Active disturbance rejection controllers based on the timely estimation of the extended state observer and compensation are then designed, guaranteeing the mean square practical convergence of the tracking errors. Some numerical simulations are performed to validate the effectiveness of the proposed control strategy.

关键词： uncertain stochastic systems active disturbance rejection control extended state observer tracking colored noise

Ligand-induced,magic-size clusters enabled formation of colloidal all-inorganic II-VI nanoplatelets with controllable lateral dimensions

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Nano Research 2023年第2期16卷 3387-3394页

作者： Xufeng Chen Junjun Ge Pengwei xiao Yalei deng Yuanyuan Wang State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Achieving nanoconfinement-controlled synthesis of nanoplatelets(NPLs)via solution process under ambient condition remains a *** this work,we developed a general ligand-induced strategy to synthesize colloidal stable all-inorganic semiconductor NPLs with controllable lateral *** introducing certain metal salts(cations:Zn^(2+)and In^(3+),anions:NO_(3)^(−),BF_(4)^(−),or triflate OTf−),wurtzite-structured(WZ-)CdS,CdSe,CdTe,and alloy Cd1−xZnxSe NPLs were directly synthesized in solution through the controlled diffusion of magic-size clusters(MSCs)at room *** studies revealed that destabilization of MSCs and nanoconfined growth in templates facilitated the formation of *** present study not only provides a new synthetic route for the preparation of NPLs but also helps to provide insight into their probable formation mechanism and presents an important advance toward the rational design of functional nanomaterials.

关键词： magic-size cluster nanoplatelets all-inorganic lateral dimensions controlled inorganic ligands

Hybrid architecture design enhances the areal capacity and cycling life of low-overpotential nanoarray oxygen electrode for lithium–oxygen batteries

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Journal of Energy Chemistry 2020年第7期29卷 248-255,I0008页

作者： Liang xiao Duo Wang Ming Li Bohua deng Jinping Liu School of Chemistry Chemical Engineering and Life ScienceWuhan University of TechnologyWuhan 430070HubeiChina State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070HubeiChina

Transition metal oxide(TMO)nanoarrays are promising architecture designs for self-supporting oxygen electrodes to achieve high catalytic activities in lithium-oxygen(Li-O2)***,the poor conductive nature of TMOs and the confined growth of nanostructures on the limited surfaces of electrode substrates result in the low areal capacities of TMO nanoarray electrodes,which seriously deteriorates the intrinsically high energy densities of Li-O2 ***,we propose a hybrid nanoarray architecture design that integrates the high electronic conductivity of carbon nanoflakes(CNFs)and the high catalytic activity of Co3 O4 nanosheets on carbon cloth(CC).Due to the synergistic effect of two differently featured components,the hybrid nanoarrays(Co3 O4-CNF@CC)achieve a high reversible capacity of3.14 mA h cm-2 that cannot be achieved by only single ***,CNFs grown on CC induce the three-dimensionally distributed growth of ultrafine Co3 O4 nanosheets to enable the efficient utilization of ***,with the high catalytic efficiency,hybrid Co3 O4-CNF@CC also achieves a more prolonged cycling life than pristine TMO *** present work provides a new strategy for improving the performance of nanoarray oxygen electrodes via the hybrid architecture design that integrates the intrinsic properties of each component and induces the three-dimensional distribution of catalysts.

关键词： Hybrid architecture Nanoarray oxygen electrode Synergistic effect Three-dimensional current collector Lithium-oxygen batteries

Pore-level numerical simulation of methane-air combustion in a simplified two-layer porous burner

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Chinese Journal of Chemical Engineering 2021年第6期34卷 87-96页

作者： Yang Liu Yangbo deng Junrui Shi Rujie xiao Houping Li Marine Engineering College Dalian Maritime UniversityDalian 116026China Naval Architecture and Ocean Engineering College Dalian Maritime UniversityDalian 116026China School of Transportation and Vehicle Engineering Shandong University of TechnologyZibo 255049China

A simplified two-dimensional model of two-layer porous burner based on pore level is *** heat transfer of solid phase in porous burner is seen as the synergistic effects of conduction through connecting bridges and surface radiation between the solid particles in the model.A numerical simulation study on the characteristics of flow,combustion and heat transfer in the two-layer porous burner is carried out using the pore level model,and the effects of the control parameters such as the inlet velocity and solid thermal conductivity on thermal non-equilibrium are *** results show that the flame structure is highly two-dimensional based on pore *** thermal non-equilibrium in the burner for the two phases and solid phase are observed,the largest temperature difference between the gas and solid phases is observed in combustion zone,while the temperature difference inside the solid particles is largest near the flame *** results also reveal that thermal non-equilibrium of porous burner is much affected by the inlet velocity and solid thermal conductivity.

关键词： Numerical simulation Porous media Thermal non-equilibrium Heat transfer Thermal conductivity

3D Free-Standing Carbon Nanofibers Modified by Lithiophilic Metals Enabling Dendrite-Free Anodes for Li Metal Batteries

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Energy & Environmental Materials 2023年第3期6卷 373-384页

作者： Huifeng Zhuang Tengfei Zhang Hong xiao xiao Liang Fanchao Zhang Jianlin deng Qiuming Gao Key Laboratory of Bio-inspired Smart Interfacial Science and Technology of Ministry of Education Beijing Advanced Innovation Center for Biomedical EngineeringSchool of ChemistryBeihang UniversityBeijing 100191China National Supercomputer Research Center of Advanced Materials Advanced Materials InstituteQilu University of TechnologyShandong Academy of SciencesJinan 250014China

Li metal with high-energy density is considered as the most promising anode for the next-generation rechargeable Li metal batteries;however,the growth of Li dendrites seriously hinders its practical ***,3D free-standing carbon nanofibers modified by lithiophilic metal particles(CNF/Me,Me=Sn,Fe,Co)are obtained in situ by the electrospinning *** from the lithophilicity,the CNF/Me composite may effectively prevent the formation of Li dendrites in the Li metal *** optimized CNF/Sn–Li composite electrode exhibits a stable cycle life of over 2350 h during Li plating/*** matched with typical commercial LiFePO_(4)(LFP)cathode,the LFP//CNF/Sn–Li full cell presents a high initial discharge specific capacity of 139 mAh g^(−1)at 1 C,which remains at 146 mAh g^(−1)after 400 *** another state-of-the-art commercial LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM(811))cathode is used,the assembled NCM//CNF/Sn–Li full cell shows a large initial specific discharge capacity of 206 mAh g^(−1)at substantially enhanced 10 C,which keeps at the good capacity of 99 mAh g^(−1)after 300 *** results are greatly superior to the counterparts with Li as the anodes,indicating the great potential for practical utilization of the advanced CNF/Sn–Li electrode.

关键词： 3D free-standing carbon nanofibers dendrite-free anodes electrospinning method lithiophilic metal lithium metal batteries

Boosting Whale Optimizer with Quasi-Oppositional Learning and Gaussian Barebone for Feature Selection and COVID-19 Image Segmentation

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Journal of Bionic Engineering 2023年第2期20卷 797-818页

作者： Jie Xing Hanli Zhao Huiling Chen Ruoxi deng Lei xiao Key Laboratory of Intelligent Informatics for Safety&Emergency of Zhejiang Province Wenzhou UniversityWenzhou325035China

Whale optimization algorithm(WOA)tends to fall into the local optimum and fails to converge quickly in solving complex *** address the shortcomings,an improved WOA(QGBWOA)is proposed in this ***,quasi-opposition-based learning is introduced to enhance the ability of WOA to search for optimal ***,a Gaussian barebone mechanism is embedded to promote diversity and expand the scope of the solution space in *** verify the advantages of QGBWOA,comparison experiments between QGBWOA and its comparison peers were carried out on CEC 2014 with dimensions 10,30,50,and 100 and on CEC 2020 test with dimension ***,the performance results were tested using Wilcoxon signed-rank(WS),Friedman test,and post hoc statistical tests for statistical *** accuracy and speed are remarkably improved,as shown by experimental ***,feature selection and multi-threshold image segmentation applications are demonstrated to validate the ability of QGBWOA to solve complex real-world *** proves its superiority over compared algorithms in feature selection and multi-threshold image segmentation by performing several evaluation metrics.

关键词： Whale optimization algorithm Quasi-opposition-based learning Gaussian barebone Image segmentation Feature selection Bionic algorithm

Design of a Bio-inspired,Two-winged,Flapping-wing Micro Air Vehicle with High-lift Performance

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Journal of Bionic Engineering 2024年第3期21卷 1191-1207页

作者： Kai Hu Huichao deng Shengjie xiao Gongyu Yang Yuhong Sun Space Robot Laboratory The School of Mechanical EngineeringBeihang UniversityBeijing100191China

In this paper,we present the development of our latest flapping-wing micro air vehicle(FW-MAV),named Explobird,which features two wings with a wingspan of 195 mm and weighs a mere 25.2 g,enabling it to accomplish vertical take-off and hover *** devised a novel gear-based mechanism for the flapping system to achieve high lift capability and reliability and conducted extensive testing and analysis on the wings to optimise power matching and lift *** Explobird can deliver a peak lift-to-weight ratio of 1.472 and an endurance time of 259 s during hover flight powered by a single-cell LiPo *** the inherent instability of the prototype,we discuss the derivatives of its longitudinal system,underscoring the importance of feedback control,position of the centre of gravity,and increased *** demonstrate the effect of damping enhancement on stability,we also designed a passive stable ***,the vehicle is actively stabilised in roll by adjusting the wing root bars and in pitch through high-authority tail control,whereas yaw is passively *** a series of flight tests,we successfully demonstrate that our prototype can perform vertical take-off and hover flight under wireless *** promising results position the Explobird as a robust vehicle with high lift capability,paving the way towards the use of FW-MAVs for carrying load equipment in multiple tasks.

关键词： Flapping wing Biologically inspired robots Mechanical design Flight dynamics Damping enhancement

Aerodynamic performance enhancement of co-flow jet airfoil with simple high-lift device

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Chinese Journal of Aeronautics 2021年第9期34卷 143-155页

作者： Haolin ZHI Zhenhao ZHU Yujin LU Shuanghou deng Tianhang xiao College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The present study performed a numerical investigation to explore the performance enhancement of a co-flow jet(CFJ)airfoil with simple high-lift device configuration,with a specific goal to examine the feasibility and capability of the proposed configuration for low-speed take-off and *** have been accomplished by an in-house-programmed Reynoldsaveraged Navier-Stokes solver enclosed by k-ωshear stress transport turbulence *** crucial geometric parameters,viz.,injection slot location,suction slot location and its angle were selected for the sake of revealing their effects on aerodynamic lift,drag,power consumption and equivalent lift-to-drag *** show that using simple high-lift devices on CFJ airfoil can significantly augment the aerodynamic associated lift and efficiency which evidences the feasibility of CFJ for short take-off and landing with small angle of *** injection and suction slot locations are more influential with respect to the aerodynamic performance of CFJ airfoil compared with the suction slot *** injection location is preferable to be located in the downstream of the pressure suction peak on leading edge to reduce the power expenditure of the pumping system for a relative higher equivalent lift-to-drag *** concluded criterion is that the suction slot should be oriented on the trailing edge flap for achieving more aerodynamic gain,meanwhile,carefully selecting this location is crucial in determining the aerodynamic enhancement of CFJ airfoil with deflected flaps.

关键词： Airfoil Co-flow jet Flow control Aerodynamic performance enhancement Simple high-lift device