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削边电极深小孔微细电火花间隙流场仿真研究

电加工与模具 2011年第3期 33-37页

作者：张雷王玉魁耿雪松王振龙哈尔滨工业大学机电工程学院黑龙江哈尔滨150001

深小孔加工是微细电火花加工的重要应用领域之一。采用削边电极加工是提高深小孔加工深径比的有效工艺手段之一。通过间隙流场仿真结合工艺实验,解释了削边电极深小孔加工提高深径比和加工速度的原因。

关键词：微细电火花加工深小孔深径比削边电极

Heat transfer and fluid flow and their effects on the solidification microstructure in full-penetration laser welding of aluminum sheet

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Journal of Materials Science & Technology 2020年第11期42卷 50-63页

作者： Shaoning geng Ping Jiang Xinyu Shao Lingyu Guo xuesong Gao The State Key Laboratory of Digital Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science Technology430074 WuhanChina Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of EducationShandong University250061 JinanChina

Understanding the behaviors of heat transfer and fluid flow in weld pool and their effects on the solidification microstructure are significant for performance improvement of laser *** paper develops a three-dimensional numerical model to understand the multi-physical processes such as heat transfer,melt convection and solidification behavior in full-penetration laser welding of thin 5083 aluminum *** parameters including temperature gradient G and solidification rate R,and their combined forms are evaluated to interpret solidification *** predicted weld dimensions and the microstructure morphology and scale agree well with *** indicate that heat conduction is the dominant mechanism of heat transfer in weld pool,and melt convection plays a critical role in microstructure *** mushy zone shape/size and solidification parameters can be modulated by changing process *** structures form because of the low G/R *** scale of dendritic structures can be reduced by increasing GR via decreasing heat *** columnar to equiaxed transition is predicted quantitatively via the process related G^3/*** findings illustrate how heat transfer and fluid flow affect the solidification parameters and hence the microstructure,and show how to improve microstructure by optimizing the process.

关键词： Laser welding Heat transfer Fluid flow Solidification microstructure Aluminum

钛合金电火花加工间隙流场排屑过程数值仿真研究

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电加工与模具 2023年第2期 17-22页

作者：郭建梅樊亚丁耿雪松何虎丁连同北京市电加工研究所有限公司电火花加工技术北京市重点实验室北京100191 航天氢能科技有限公司北京100071 西安航天发动机有限公司陕西西安710100

采用数值模拟方法对电火花加工过程中间隙流场的碎屑排出情况进行仿真研究。计算结果表明,在电极的上升段,大量粒子被带出凹槽,排屑效果显著;在电极的下降段,仍有部分粒子被继续排出间隙区域。对比不同尺寸的钛合金粒子分布可以发现,排... 详细信息

采用数值模拟方法对电火花加工过程中间隙流场的碎屑排出情况进行仿真研究。计算结果表明,在电极的上升段,大量粒子被带出凹槽,排屑效果显著;在电极的下降段,仍有部分粒子被继续排出间隙区域。对比不同尺寸的钛合金粒子分布可以发现,排出粒子的数量随粒子直径的增加而减小,说明小粒子更易被排出。对流场内速度矢量分布进行分析可以发现,在电极上升过程中,其下表面下方区域存在涡结构,这是排出颗粒粒子的主要动力;在电极下降过程中,涡结构出现在间隙区域上方电极两侧,继续带动部分粒子排出。

关键词：电火花加工排屑过程数值仿真

微细电火花加工模糊抬刀控制系统的设计及实验研究

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电加工与模具 2012年第1期 15-19页

作者：迟关心耿雪松王玉魁王振龙哈尔滨工业大学机电工程学院黑龙江哈尔滨150001

提出了一种基于VC++和MATLAB混合编程、进行微细电火花模糊抬刀控制系统的设计方法。该系统的设计是基于电火花加工状态统计、以抬刀高度和抬刀周期为控制量进行的,模糊运算利用MATLAB模糊控制工具箱进行,可实现模糊控制规则的可视化在... 详细信息

提出了一种基于VC++和MATLAB混合编程、进行微细电火花模糊抬刀控制系统的设计方法。该系统的设计是基于电火花加工状态统计、以抬刀高度和抬刀周期为控制量进行的,模糊运算利用MATLAB模糊控制工具箱进行,可实现模糊控制规则的可视化在线修正;通过控制器算法C语言代码的自动生成,在实现模糊控制脱离MATLAB环境独立运行的同时,保证了算法生成的正确性;进行了基于VC环境下模糊控制器算法的封装,通过与自行研制的机床数控系统软件动态链接的方式,实现了微细电火花模糊抬刀控制系统的搭建。通过基于放电时间的微细电火花放电状态检测技术的研究,旨在提高该模糊抬刀控制系统的准确性。最后通过微细阵列孔电火花加工实验,验证了该模糊抬刀控制系统的有效性。

关键词：微细电火花加工混合编程模糊控制技术抬刀

Characteristics of particulate-bound polycyclic aromatic hydrocarbons emitted from industrial grade biomass boilers

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Journal of Environmental Sciences 2016年第2期28卷 28-34页

作者： Xiaoyang Yang Chunmei geng xuesong Sun Wen Yang Xinhua Wang Jianhua Chen State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Beijing 100012China Beijing Municipal Research Institute of Environmental Protection Beijing 100037 China

Polycyclic aromatic hydrocarbons（PAHs） are carcinogenic or mutagenic and are important toxic pollutants in the flue gas of boilers. Two industrial grade biomass boilers were selected to investigate the characteristics of particulate-bound PAHs： one biomass boiler retro-fitted from an oil boiler（BB1） and one specially designed（BB2） biomass boiler. One coal-fired boiler was also selected for comparison. By using a dilution tunnel system, particulate samples from boilers were collected and 10 PAH species were analyzed by gas chromatography–mass spectrometry（GC–MS）. The total emission factors（EFs） of PAHs ranged from 0.0064 to0.0380 mg/kg, with an average of 0.0225 mg/kg, for the biomass boiler emission samples. The total PAH EFs for the tested coal-fired boiler were 1.8 times lower than the average value of the biomass boilers. The PAH diagnostic ratios for wood pellets and straw pellets were *** ratio of indeno（1,2,3-cd）pyrene/[indeno（1,2,3-cd）pyrene ＋ benzo（g,h,i）perylene] for the two biomass boilers was lower than those of the reference data for other burning devices, which can probably be used as an indicator to distinguish the emission of biomass boilers from that of industrial coal-fired boilers and residential stoves. The toxic potential of the emission from wood pellet burning was higher than that from straw pellet burning, however both of them were much lower than residential stove exhausts.

关键词： Polycyclic aromatic hydrocarbons Industrial grade biomass boiler Emission factor Diagnostic ratio Potential toxicity risk

Emission factors, ozone and secondary organic aerosol formation potential of volatile organic compounds emitted from industrial biomass boilers

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Journal of Environmental Sciences 2019年第9期31卷 64-72页

作者： Chunmei geng Wen Yang xuesong Sun Xinhu Wang Zhipeng Bai Xia Zhang State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Beijing 100012 China Beijing Municipal Research Institute of Environmental Protection Beijing 100037 China China National Environmental Monitoring Centre Beijing 100012 China

To evaluate the potential benefits of biomass use for air pollution control, this paper identified and quantified the emissions of major reactive organic compounds anticipated from biomass-fired industrial boilers. Wood pellets(WP) and straw pellets(SP) were burned to determine the volatile organic compound emission profiles for each biomass-boiler combination. More than 100 types of volatile organic compounds(VOCs) were measured from the two biomass boilers. The measured VOC species included alkanes, alkenes and acetylenes, aromatics, halocarbons and carbonyls. A single coal-fired boiler(CB) was also studied to provide a basis for comparison. Biomass boiler 1(BB1) emitted relatively high proportions of alkanes(28.9%–38.1% by mass) and alkenes and acetylenes(23.4%–40.8%),while biomass boiler 2(BB2) emitted relatively high proportions of aromatics(27.9%–29.2%)and oxygenated VOCs(33.0%–44.8%). The total VOC(TVOC) emission factors from BB1(128.59–146.16 mg/kg) were higher than those from BB2(41.26–85.29 mg/kg). The total ozone formation potential(OFP) ranged from 6.26 to 81.75 mg/m^3 with an average of 33.66 mg/m^3 for the two biomass boilers. The total secondary organic aerosol potential(SOAP) ranged from 61.56 to 211.67 mg/m^3 with an average of 142.27 mg/m^3 for the two biomass *** emission factors(EFs) of TVOCs from biomass boilers in this study were similar to those for industrial coal-fired boilers with the same thermal power. These data can supplement existing VOC emission factors for biomass combustion and thus enrich the VOC emission inventory.

关键词： Biomass boiler Volatile organic compounds(VOCs) Emission factor Ozone formation potential(OFP) Secondary organic aerosol potential(SOAP)

Influence of reconstruction techniques on PET/CT image quality and quantitative accuracy:a phantom study

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Radiation Detection Technology and Methods 2024年第2期8卷 1171-1186页

作者： xuesong Su Jianhua geng Jianing Liu Fengshuo Liu Yichen Wu Rong Zheng Xuejuan Wang Department of Nuclear Medicine National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100021China

Purpose To investigate the influence of different reconstruction techniques on the quantitative accuracy and image quality of PET/*** The NEMA NU2-2018 image quality phantom was scanned on a GE Discovery Elite PET/CT scanner and the spatial resolution was measured based on NEMA NU2 *** same raw data were reconstructed using five different algorithms:ordered subset expectation maximization(OSEM),OSEM with point spread function(PSF)modeling,OSEM with time-of-flight(TOF),OSEM with TOF and PSF,and filtered back-projection(FBP).The recovery coefficient(RC),contrast recovery coefficient(CRC),and contrast-to-noise ratio(CNR)were calculated for the six hot spheres,the percent background variability(PBV)and coefficient of variation(COV)were calculated for the background,and the residual error(RE)was calculated for lung insert in different image *** The incorporation of PSF modeling showed the smallest transverse FWHM and FWTM at both 1 and 10 cm radical *** combination of PSF modeling and TOF improved RCmean and CRC for all spheres and resulted in the highest ratings for the detectability of 10 mm spheres in human observer *** modeling played a role in reducing the COV within the background region of interest and increasing the CNR of the spheres,and decreased background noise ratings in human observer ***,TOF significantly reduced the RE in lung *** PSF modeling nor TOF had a significant effect on *** to FBP,the OSEM algorithm showed significant advantages in PBV,COV,CNR and RE and human observer ratings of image quality,but worse results for RC_(max),RC_(mean) and *** The integration of TOF and PSF modeling into the OSEM algorithm achieves improvements in both quantitative accuracy and image quality,providing distinct *** modeling improves the spatial resolution and decreases the visual appearance of background *** OSEM algorithm shows significantly better image qu

关键词： Positron emission tomography(PET) Image quality Quantification accuracy Reconstruction techniques Phantom

A ZigBee-Based Acquisition System for Agricultural Environment Information with Low Power and High Reliability

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Journal of Computer and Communications 2018年第9期6卷 39-49页

作者： Guiling Sun xuesong Guo Tianyu geng Yawen Du College of Electronic Information and Optical Engineering Nankai University Tianjin China

In order to guarantee the safety of products at modern agriculture, the whole factors of the environment of agricultural production process need to be monitored. That needs to collect a variety of environmental information. In this paper, based on ZigBee technology, a system for crop growth environment information and image information acquisition is implemented. System network scheme can reduce the interchannel interference and enhance ZigBee communication quality. In the process of transmission, the transmission of the image data uses a coding scheme based on historical data comparison. For the image transmission, an intelligent transmission scheme based on generating Feedback Report is proposed, which takes both the quality and efficiency into consideration. Based on these schemes, the system designed in this paper can realize efficient and reliable transmission of agricultural environmental information.

关键词： ZigBee Wireless Networking Agricultural Internet of Things Image Transmission

Knockout of miR396 genes increases seed size and yield in soybean

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Journal of Integrative Plant Biology 2024年第6期66卷 1148-1157页

作者： Hongtao Xie Fei Su Qingfeng Niu Leping geng xuesong Cao Minglei Song Jinsong Dong Zai Zheng Rui Guo Yang Zhang Yuanwei Deng Zhanbo Ji Kang Pang Jian‐Kang Zhu Jianhua Zhu School of Life Sciences Anhui Agricultural UniversityHefei 230036China Research Center for Biological Breeding Technology Research Institute of Frontier ScienceAnhui Agricultural UniversityHefei 230036China Bellagen Biotechnology Co.Ltd Jinan 250000China Institute of Crop Sciences/National Nanfan Research Institute Chinese Academy of Agricultural SciencesKey Laboratory of Gene Editing Technologies(Hainan)Ministry of Agriculture and Rural AffairsSanya 572025China Southern University of Science and TechnologyShenzhen 518055China Hainan Yazhou Bay Seed Laboratory Sanya 572024China

Yield improvement has long been an important task for soybean breeding in the world in order to meet the increasing demand for food and animal *** R396 genes have been shown to negatively regulate grain size in rice,but whether mi R396 family members may function in a similar manner in soybean is ***,we generated eight soybean mutants harboring different combinations of homozygous mutations in the six soybean mi R396genes through genome editing with clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated nuclease(Cas)12SF01 in the elite soybean cultivar Zhonghuang 302(ZH302).Four triple mutants(mir396aci,mir396acd,mir396adf,and mir396cdf),two quadruple mutants(mir396-abcd and mir396acfi),and two quintuple mutants(mir396abcdf and mir396bcdfi)were *** found that plants of all the mir396 mutants produced larger seeds compared to ZH302 *** tests showed that mir396adf and mir396cdf plants have significantly increased yield in growth zones with relatively high latitude which are suited for ZH302 and moderately increased yield in lower *** contrast,mir396abcdf and mir396bcdfiplants have increased plant height and decreased yield in growth zones with relatively high latitude due to lodging issues,but they are suited for low latitude growth zones with increased yield without lodging *** together,our study demonstrated that loss-of-function of mi R396 genes leads to significantly enlarged seed size and increased yield in soybean,providing valuable germplasms for breeding high-yield soybean.

关键词： Cas12SF01 CRISPR/Cas miR396 seed size soybean yield