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Microsystems & Nanoengineering 2020年第1期6卷 1187-1198页

作者： Yanfang guan Baichuan Sun School of Electromechanical Engineering Henan University of technologyZhengzhou 450001China

As a promising concept,microfluidic paper-based analytical devices(μPADs)have seen rapid development in recent *** this study,a new method of fabricatingμPADs by atom stamp printing(ASP)is proposed and *** advantages of this new method compared to other methods include its low cost,ease of operation,high production efficiency,and high resolution(the minimum widths of the hydrophilic channels and hydrophobic barriers are 328 and 312μm,respectively).As a proof of concept,μPADs fabricated with the ASP method were used to detect different concentrations of Cu^(2+)via a colorimetric ***,combined with a distance-based detection method,these devices achieved a Cu^(2+)detection limit of down to 1mg/*** addition,a new paper-based solid–liquid extraction device(PSED)based on a three-dimensional(3D)μPAD with a“3+2”structure and a recyclable extraction mode was ***,using the characteristics of paper filtration and capillary force,the device completed multiple extraction and filtration steps from traditional solid–liquid extraction processes with high *** developed PSED platform allows the detection of heavy metal ions much more cheaply and simply and with a faster response time at the point of care,and it has great promise for applications in food safety and environmental pollution in resource-limited areas.

关键词： printing analytical faster

Optimizational production of phenyllactic acid by a Lactobacillus buchneri strain via uniform design with overlay sampling methodology

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Chinese Journal of Chemical Engineering 2019年第2期27卷 418-425页

作者： Jintao guan Chaofei Han Yixin guan Songhong Zhang Junxian Yun Shanjing Yao College of Chemical and Biological Engineering Zhejiang University State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology College of Chemical Engineering Zhejiang University of Technology

A Lactobacillus buchneri GBS3 strain isolated from the traditional Chinese pickles was used for the production of 3-phenyllactic acid(PLA), an important compound with antimicrobial activities against a wide species of grampositive and gram-negative bacteria and some fungi. The growth performance of this strain in the de Man, Rogosa and Sharpe(MRS) medium, the production of metabolites of valuable organic acids, and the biosynthesis of PLA using this strain as the whole-cell biocatalyst and phenylpyruvic acid(PPA) as the precursor, were investigated experimentally. The uniform design method with overlay sampling was developed for the optimization of the biotransformation conditions. The results showed that although it produced naturally lactic acid with the maximum concentration of 1.84 g·L^(-1) and PLA with the concentration of 0.015 g·L^(-1) after 66 to 72 h cultivation in MRS broth by fermentation, the present strain displayed an effective utilization ability by transforming PPA to PLA. By the uniform design method with overlay sampling for the design and optimization of transformation conditions, a maximum yield of 10.93 g·L^(-1) PLA with the mole conversion ratio of 83.07% from PPA to PLA was achieved under the optimized condition, i.e., 20 g·L^(-1) glucose, 270 g·L^(-1) cells, 13 g·L^(-1) PPA, pH 8.0 and the reaction time of 15 h, indicating that Lactobacillus buchneri GBS3 was an interesting strain for the biosynthesis of PLA via the microbial transformation. The prediction of PLA yield under different conditions was achieved successfully based on the limited information of only a small number of experiments by the uniform design with overlay sampling. Therefore, the present methodology is effective and helpful for the optimization of the biosynthesis processes of PLA.

关键词： Phenyllactic Acid Biotransformati on Lactobacillus Buchneri Uniform Design Overlap Sampling

Removal and utilization of calcite existed in scheelite by preparation of calcium sulfate whiskers

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International Journal of Mining Science and Technology 2017年第6期27卷 1005-1010页

作者： guan Qingjun Sun Wei Hu Yuehua guan Changping Yin Zhigang Zhang Chenhu School of Mineral Processing and Bioengineering Central South University Changsha 410083 China

In order to eliminate the effect of calcite associated with scheelite on the scheelite flotation, hydrochloric acid was used to dissolve the calcite, and the soaking solution was used to prepare CaSO_4 whiskers by hydrothermal reaction with sulfuric acid at ambient pressure. First, the condition experiments of preparing CaSO_4 whiskers by using CaCl_2 and H_2SO_4 were carried out to optimize reaction parameters of the crystallization process. The optimal conditions were: at 102 ℃ reaction temperature, 0,5 mol/L reactant concentration and 60 min reaction time. Then based on the condition experiments and considering keeping acid concentration stable for achieving HCl recycling, Calcium sulfate whiskers with the average diameter of 1.41 μm and the average aspect ratio of 109 were prepared by the soaking solution after evaporating to half of its volume and 1.0 mol/L H_2SO_4 at 102 ℃ for 60 min: After ion exchange processing,the filtrate could be used as HCl in the process of HCl dissolution.

关键词： Calcium sulfate whiskers Scheelite Calcite HCl Hydrothermal reaction

A Newly Developed Wrought Ni–Fe–Cr-based Superalloy for Advanced Ultra-Supercritical Power Plant Applications Beyond 700℃

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Acta Metallurgica Sinica(English Letters) 2015年第9期28卷 1083-1088页

作者： Shuai guan Chuan-Yong Cui Institute of Metal Research Chinese Academy of Sciences

Some existing wrought Ni-Cr-Co-based superalloys are being evaluated as the candidate materials for advanced ultra-supercritical power plant applications beyond 700 ℃ due to their high creep strength. But they are all prohibitively expensive due to the addition of Co, Mo and W. Here we developed a new Ni-Fe-Cr-based superalloy （named as HT700 alloy） with low cost and high strength. This paper reports the mechanical properties and fracture modes of HT700 alloy to support its high temperature applications and to understand prospective failure mechanism. Fracto- graphic examinations indicate that the fracture modes shift with test condition change. In addition, the HT700 alloy has relatively stable microstructure at 750 ℃. Compared with IN740 and GH2984 alloys, this new alloy has higher yield strength in the temperature range from room temperature to 800 ℃. The creep life of this new alloy is much longer than that of the Ni-Fe-based superaUoy GH2984. The results suggest that this new alloy is a promising material for advanced ultra-supercritical power plant applications beyond 700 ℃.

关键词： Wrought Ni-Fe-Cr-based superalloy Low cost High strength Fracture mode

Study on the Prediction System of Shrimp Field Distribution in the East China Sea Based on Big Data Analysis of Fishing Trajectories

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Journal of Ocean University of China 2021年第1期20卷 228-234页

作者： guan Huanhuan ZHAO Xueli Management College Ocean University of ChinaQingdao 266100China College of Information Science and Engineering Ocean University of ChinaQingdao 266100China

In recent years,China has paid more and more attention to the development of marine economy and the management and protection of fishery *** management departments at all levels regulate and manage the fishing behavior of fishing vessels through the data of fishing *** this paper,the distribution of shrimp farms in the East China Sea is predicted by studying the trajectories and behavior patterns of shrimp boats in the system of fishing *** the same time,a set of shrimp farm distribution management system based on Back Propagation algorithm is *** can monitor the trajectories of fishing boats and the distribution of shrimp groups in real time,which effectively improves the work efficiency and management mode of the management *** also plays a positive role in regulating the behavior of fishing boats at sea.

关键词： BP algorithm big data shrimp farm distribution fishery management

A-STC: auction-based spanning tree coverage algorithm for motion planning of cooperative robots

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Frontiers of Information Technology & Electronic Engineering 2019年第1期20卷 18-31页

作者： guan-qiang GAO Bin XIN School of Automation Beijing Institute of Technology Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing Advanced Innovation Center for Intelligent Robots and Systems

The multi-robot coverage motion planning(MCMP) problem in which every reachable area must be covered is common in multi-robot systems. To deal with the MCMP problem, we propose an efficient, complete, and off-line algorithm, named the "auction-based spanning tree coverage(A-STC)" algorithm. First, the configuration space is divided into mega cells whose size is twice the minimum coverage range of a robot. Based on connection relationships among mega cells, a graph structure can be obtained. A robot that circumnavigates a spanning tree of the graph can generate a coverage trajectory. Then, the proposed algorithm adopts an auction mechanism to construct one spanning tree for each robot. In this mechanism, an auctioneer robot chooses a suitable vertex of the graph as an auction item from neighboring vertexes of its spanning tree by heuristic rules. A bidder robot submits a proper bid to the auctioneer according to the auction vertexes' relationships with the spanning tree of the robot and the estimated length of its trajectory. The estimated length is calculated based on vertexes and edges in the spanning tree. The bidder with the highest bid is selected as a winner to reduce the makespan of the coverage task. After auction processes, acceptable coverage trajectories can be planned rapidly. Computational experiments validate the effectiveness of the proposed MCMP algorithm and the method for estimating trajectory lengths. The proposed algorithm is also compared with the state-of-the-art algorithms. The comparative results show that the A-STC algorithm has apparent advantages in terms of the running time and the makespan for large crowded configuration spaces.

关键词： Coverage motion planning Multi-robot system Auction algorithm Spanning tree coverage algorithm

A capture probability analytic model for the electromagnetic launched anti-torpedo torpedo

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Defence Technology（防务技术） 2022年第2期18卷 261-270页

作者： Bao-qi Wu Xiao-cun guan Shao-hua guan Jing-bin Shi National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of EngineeringWuhan430033China Jiangsu Automation Research Institute Lianyungang 222006China

With the unique characteristics,electromagnetic launch technology is applicable to launch shipborne anti-torpedo torpedo(ATT).This paper aims to establish an analytic model to pre-evaluate the capture probability of the electromagnetic launched *** mathematics model of the multi-stage coilgun and the trajectory of the ATT is established for *** influence factors of the capture probability are analyzed respectively,including the entry point dispersion of the ATT and the position dispersion of the incoming *** the advanced angle interception mode,the ATT search model is obtained according to the positional relationship,and the course error is synthetically calculated according to the differentiation of implicit function.A geometric method to calculate the integral boundaries of the probability density function is proposed,based on the relative motion of the ATT and the incoming *** verify the proposed integral model,the digital simulation and comparison is *** results reveal that the variation trends and the calculation value of the proposed analytic model are coincident with the statistic results from Monte Carlo *** implications of the results regarding the analytic model are discussed.

关键词： Electromagnetic launch Anti-torpedo torpedo Analytic model Dispersion variance Integral boundary

PRESSURE CORRECTION METHOD ON UNSTRUCTURED GRIDS

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Journal of Hydrodynamics 2004年第3期16卷 316-324页

作者： LAIXi-jun WANGDe-guan CHENYang NangjingInstituteofGeographyandLimnology ChineseAcademyofSciencesNangjing210008China CollegeofEnvironmentalScienceandEngineering HohaiUniversityNanjing210098China

In this paper, an unstructured, collocated finite volume method for solvingthe Navier-Stokes equations was developed by virtue of auxiliary points. The derivatives weredetermined by the Gauss theorem. The proposed method could provide control volumes with arbitrarygeometry and preserve the second-order accuracy even if highly distorted grids are used. Althougharbitrary number of cell faces can be used, the hybrid quadrilateral/triangular grids are moredesirable for the simplicity of implementation and applications to engineering problems. Thepressure-velocity coupling was treated using a SIMPLE-like algorithm. The Generalized MinimumResidual (GMRES) method with the Incomplete LU (ILU) preconditioner was used to solve linearequations. Four test cases were studied for validating the proposed method. In using this method,grid quality is not important. Thus, engineers can pay mostly attention to physical mechanism ofproblems. Turbulence models can be simply integrated and the method can be straightforwardlyextended to treat three-dimensional problems.

关键词： finite volume method unstructured grids generalized minimum residual(GMRES) method incomplete LU (ILU) preconditioner

A Review on Grain Refinement of Aluminum Alloys:Progresses,Challenges and Prospects

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Acta Metallurgica Sinica(English Letters) 2017年第5期30卷 409-432页

作者： Ren-Guo guan Di Tie School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

Aluminum becomes the most popular nonferrous metal and is widely used in many fields such as packaging,building transportation and electrical materials due to its rich resource, light weight, good mechanical properties, suitable corrosion resistance and excellent electrical conductivity. Grain refinement, which is obtained by changing the size of grain structure by different techniques, is a preferred method to improve simultaneously the strength and plasticity of metallic materials. Therefore, grain refining of aluminum is regarded as a key technique in aluminum processing *** to now, there have been a number of techniques for aluminum grain refining. All the techniques can be classified as four categories as follows： grain refining by vibration and stirring during solidification, rapid solidification, the addition of grain refiner and severe plastic deformation. Each of them has its own merits and demerits as well as applicable conditions, and there are still some arguments in the understanding of the mechanisms of these techniques. In this article, the research progresses and challenges encountered in the present techniques and the future research issues and directions are summarized.

关键词： Aluminum Grain refinement Vibration and stirring Rapid solidification Grain refiner Severe plastic deformation

Study of the mechanics of progressive collapse of FPB isolated beam-pier substructures

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Frontiers of Structural and Civil Engineering 2022年第6期16卷 718-728页

作者： Jingcai ZHANG Yong DING Xinchun guan Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of TechnologyHarbin 150090China Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information Harbin Institute of TechnologyHarbin 150090China

The horizontal stiffness of the isolated layer is reduced substantially by a friction pendulum bearing(FPB)toprotectthe structure from potential damages caused by ***,horizontal stiffness is essential to progressive collapse resistance of *** paper presents a simplified model to assess the progressive collapse response of beam-pier substructure isolated by *** collapse resistance by flexural action of the beam and additional resistance owing to the horizontal restraining force was *** influences of the equivalent radius and friction coefficient of the FPB,the applied axial force on the FPB,and span-depth ratio of the beam on the additional resistance were *** were conducted to verify the proposed *** results show that progressive collapse resistance provided by horizontal restraining can be reduced as large as 46%and 88%during compressive arching action(CAA)and catenary action(CA),*** equivalent radius of the FPB shows limited effect on the progressive collapse response of FPB isolated structures,but friction coefficient and applied axial force,as well as depth ratio of the beam,show significant influences on the additional progressive collapse resistance *** element method(FEM)results are in good agreement with the result obtained by the proposed method.

关键词： friction pendulum bearing progressive collapse horizontal stiffness compressive arching action catenary action