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Science China(Technological Sciences) 2021年第8期64卷 1611-1623页

作者： ZHENG ZunQing liu Wei liu haifeng FENG Lei CUI YanQing ZHANG Shuo YAO MingFa State Key Laboratory of Engines Tianjin UniversityTianjin300072China

In this paper,high-speed imaging and spectrometry diagnostics were used to study the spray flame structures and emission spectra of polyoxymethylene dimethyl ethers(PODE)in an optical constant volume *** effects of oxygen volume fraction(15%to 80%)on some typical combustion characteristics such as spatially integrated natural intensity,flame propagation speed,lift-off length and the distribution of flame emission spectra were *** results show that the PODE spray flame mainly exhibits blue chemiluminescence,which is different from the diesel yellow diffusion flame dominated by soot *** the oxygen concentration increases,the flame natural luminosity and propagation speed increases,the position of lift-off region and flame tip move towards the injector nozzle,and the flame width becomes *** to the spectral results,the blue chemiluminescence generated by carbon monoxide oxidation dominates the PODE flame luminescence,suggesting that no soot is *** increase in oxygen concentration leads to enlarged intensity and gradient of PODE flame *** summary,the combination of PODE and oxygen-enriched combustion shows no soot formation and promotes the oxidation of carbon monoxide and unburned *** study can provide more insights into PODE spray combustion,and offer guidelines for achieving efficient and clean combustion.

关键词： polyoxymethylene dimethyl ethers oxygen enrichment spray flame constant volume vessel optical diagnostics smokeless combustion

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商用车传动系统阻力试验分析及应用

汽车零部件 2024年第1期 82-86页

作者：曹辉刘海峰廖善彬蔡利平赵责峻徐东辉江铃汽车股份有限公司新能源新动力院江西南昌330200 南昌师范学院数学与计算机科学系江西南昌330032

针对汽车传动阻力会造成能量损失及影响油耗的问题,以商用车前置后驱车型为对象,利用四驱动力总成台架对汽车5处传动系部件阻力进行试验研究,探索各部件的阻力规律。试验结果表明,驱动桥对传动系阻力影响的占比最大。对比不同型号润滑... 详细信息

针对汽车传动阻力会造成能量损失及影响油耗的问题,以商用车前置后驱车型为对象,利用四驱动力总成台架对汽车5处传动系部件阻力进行试验研究,探索各部件的阻力规律。试验结果表明,驱动桥对传动系阻力影响的占比最大。对比不同型号润滑油和不同油温下的驱动桥阻力发现,驱动桥阻力与润滑油温度的相关性很大。

关键词：前置后驱传动阻力驱动桥润滑油

Effect of the projector augmented wave potentials on the simulation of thermodynamic properties of vanadium

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Matter and Radiation at Extremes 2021年第6期6卷 86-93页

作者： Tingting Zhang Yuechao Wang Jiawei Xian Shuaichuang Wang Jun Fang Suqing Duan Xingyu Gao haifeng Song haifeng liu Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100094China

We report significant differences in high-pressure properties of vanadium at zero temperature and finite temperature when different projector augmented wave(PAW)potentials are used in simulations based on density functional *** a PAW potential with only five electrons taken as valence electrons is used,the cold pressures in the high-pressure region are seriously underestimated,and an abnormality occurs in the melting curve of vanadium at about 400 *** show that the reason for these discrepancies lies in the differences in the descriptions of the interatomic force,electron dispersion,and anisotropy of electron bonding obtained from differentPAWpotentials at high pressure,which lead to striking differences in the mechanical stability of the *** propose a procedure for selecting PAW potentials suitable for simulations at high temperature and high *** results provide valuable guidance for future simulations of thermodynamic properties under extreme conditions.

关键词： vanadium thermodynamic wave

Performance study of vertical MSM solar-blind photodetectorsbased onβ-Ga_(2)O_(3)thin film

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 17-27页

作者： Chen haifeng Che Lujie Lu Qin Wang Shaoqing liu Xiangtai liu Zhanhang Guan Youyou Zhao Xu Cheng Hang Han Xiaocong Zhang Xuhui School of Electronic Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China

In this work,β-Ga_(2)O_(3)thin films were grown on SiO_(2)substrate by atomic layer deposition(ALD)and annealed in N_(2)atmosphere to enhance the crystallization quality of the thin films,which were verified from X-rays diffraction(XRD).Based on the grownβ-Ga_(2)O_(3)thin films,vertical metal-semiconductor-metal(MSM)interdigital photodetectors(PDs)were fabricated and *** PDs have an ultralow dark current of 1.92 pA,ultra-high photo-to-dark current ratio(PDCR)of 1.7×10^(6),and ultra-high detectivity of 4.25×10^(14)Jones at a bias voltage of 10 V under 254 nm deep ultraviolet(DUV).Compared with the horizontal MSM PDs under the same process,the PDCR and detectivity of the fabricated vertical PDs are increased by 1000 times and 100 times,*** addition,the vertical PDs possess a high responsivity of 34.24 A/W and an external quantum efficiency of 1.67×10^(4)%,and also exhibit robustness and repeatability,which indicate excellent *** the effects of electrode size and external irradiation conditions on the performance of the vertical PDs continued to be investigated.

关键词： Ga_(2)O_(3) atomic layer deposition(ALD) annealing vertical metal-semiconductor-metal(MSM)interdigital photodetectors

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Particle detector readout integrated circuit of 0.18μm technology with 164 e equivalent noise charge

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Nuclear Science and Techniques 2011年第6期22卷 358-365页

作者： LI Xiangyu liu haifeng ZHANG Qi SUNYihe Tsinghua National Laboratory for Information Science and Technology Institute of Mieroelectronics Tsinghua University Beijing 100084 China

Integrated circuits of deep submicron(DSM) CMOS technology are advantageous in volume density, power consumption and thermal noise for multichannel particle detection systems,but there are challenges in the front-end circuit *** this paper,we present a 0.18μm CMOS front-end readout circuit for low noise CdZnTe detectors in tens of pF *** to the noise and gate leak problems in DSM technologies are discussed in detail.A prototype chip was designed,with a charge sensitive preamplifier,a 4th order semi-Gaussian shaper and several output *** results show that the chip has an equivalent noise charge of 164 e,without connecting it to a detector,with an integral nonlinearity of<0.21%and differential nonlinearity of<3.75%.

关键词：电荷灵敏前置放大器 CMOS技术粒子探测器集成电路热噪声前端电路设计 DSM技术读数

Wear-resistant CoCrNi multi-principal element alloy at cryogenic temperature

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Science Bulletin 2024年第2期69卷 227-236页

作者： Yue Ren Qing Zhou Dongpeng Hua Zhuobin Huang Yulong Li Qian Jia Peter Gumbsch Christian Greiner haifeng Wang Weimin liu State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi’an 710072China Institute for Applied Materials Karlsruhe Institute of TechnologyKarlsruhe 76131Germany IAM-ZM MicroTribology CenterμTC Karlsruhe Institute of TechnologyKarlsruhe 76131Germany Fraunhofer IWM Freiburg 79108Germany State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Traditional high strength engineering alloys suffer from serious surface brittleness and inferior wear performance when servicing under sliding contact at cryogenic ***,we report that the recently emerging CoCrNi multi-principal element alloy defies this trend and presents dramatically enhanced wear resistance when temperature decreases from 273 to 153 K,surpassing those of cryogenic austenitic *** temperature-dependent structure characteristics and deformation mechanisms influencing the cryogenic wear resistance of CoCrNi are clarified through microscopic observation and atomistic *** is found that sliding-induced subsurface structures show distinct scenarios at different deformation *** cryogenic condition,significant grain refinement and a deep plastic zone give rise to an extended microstructural gradient below the surface,which can accommodate massive sliding deformation,in direct contrast to the strain localization and delamination at 273 ***,the temperature-dependent cryogenic deformation mechanisms(stacking fault networks and phase transformation)also provide additional strengthening and toughening of the subsurface *** features make the CoCrNi alloy particularly wear resistant at cryogenic conditions and an excellent candidate for safety–critical applications.

关键词： Multi-principal element alloy Cryogenic temperature Wear CoCrNi

A Secure Device Management Scheme with Audio-Based Location Distinction in IoT

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工程与科学中的计算机建模(英文) 2024年第1期138卷 939-956页

作者： haifeng Lin Xiangfeng liu Chen Chen Zhibo liu Dexin Zhao Yiwen Zhang Weizhuang Li Mingsheng Cao College of Economics and Management Nanjing University of Aeronautics and AstronauticsNanjing211106China Chengdu Aircraft Industrial(Group)Co. Ltd.Chengdu610073China Academy of Military Sciences of PLA Beijing100091China School of Information and Software Engineering University of Electronic Science and Technology of ChinaChengdu610054China Ningbo Web King Technology Joint Stock Co. Ltd.Ningbo315000China The Network and Data Security Key Laboratory of Sichuan Province University of Electronic Science and Technology of ChinaChengdu610054China

Identifying a device and detecting a change in its position is critical for secure devices management in the Internet of Things(IoT).In this paper,a device management system is proposed to track the devices by using audio-based location distinction *** the proposed scheme,traditional cryptographic techniques,such as symmetric encryption algorithm,RSA-based signcryption scheme,and audio-based secure transmission,are utilized to provide authentication,non-repudiation,and confidentiality in the information interaction of the management ***,an audio-based location distinction method is designed to detect the position change of the ***,the audio frequency response(AFR)of several frequency points is utilized as a device *** device signature has the features as follows.(1)Hardware Signature:different pairs of speaker and microphone have different signatures;(2)Distance Signature:in the same direction,the signatures are different at different distances;and(3)Direction Signature:at the same distance,the signatures are different in different *** on the features above,amovement detection algorithmfor device identification and location distinction is ***,a secure communication protocol is also proposed by using traditional cryptographic techniques to provide integrity,authentication,and non-repudiation in the process of information interaction between devices,Access Points(APs),and *** experiments are conducted to evaluate the performance of the proposed *** experimental results show that the proposedmethod has a good performance in accuracy and energy consumption.

关键词： Acoustic hardware fingerprinting device management IoT location distinction

Opposed multi-burner gasification technology:Recent process of fundamental research and industrial application

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Chinese Journal of Chemical Engineering 2021年第7期34卷 124-142页

作者： Fuchen Wang Guangsuo Yu haifeng liu Weifeng Li Qinghua Guo Jianliang Xu Yan Gong Hui Zhao haifeng Lu Zhongjie Shen Institute of Clean Coal Technology East China University of Science and TechnologyNational Engineering Research Center of CWS Gasification and Coal Chemical Industry(Shanghai)East China University of Science and TechnologyShanghai 200237China

Opposed multi-burner(OMB)gasification technology is the first large-scale gasification technology developed in China with completely independent intellectual property *** has been widely used around the world,involving synthetic ammonia,methanol,ethylene glycol,coal liquefaction,hydrogen production and other *** paper summarizes the research and development process of OMB gasification technology from the perspective of the cold model experiment and process simulation,pilotscale study and industrial *** latest progress of fundamental research in nozzle atomization and dispersion,mixing enhancement of impinging flow,multiscale reaction of different carbonaceous feedstocks,spectral characteristic of impinging flame and particle characteristics inside gasifier,and comprehensive gasification model are *** latest industrial application progress of ultralarge-scale OMB gasifier and radiant syngas cooler(RSC)combined with quenching chamber OMB gasifier are introduced,and the prospects for the future technical development are proposed as well.

关键词： Opposed multi-burner Gasification Multiscale Numerical simulation Industrial application

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普洱咖啡品质特征分析

中国热带农业 2024年第3期 49-56,69页

作者：陈保王筱楠王丽芳姜东华罗正刚李晓娇刘海峰普洱市质量技术监督综合检测中心云南普洱665099 云南咖啡交易中心有限公司云南普洱665099

普洱咖啡是国家地理标志保护产品,为研究普洱咖啡品质特征,采集普洱咖啡地理标志产品保护范围内的生咖啡样品,测定咖啡的内含成分及杯测分数,分析普洱咖啡的品质特点,同时与云南其他产区咖啡及国外咖啡进行对比。结果表明,不同产地普洱... 详细信息

普洱咖啡是国家地理标志保护产品,为研究普洱咖啡品质特征,采集普洱咖啡地理标志产品保护范围内的生咖啡样品,测定咖啡的内含成分及杯测分数,分析普洱咖啡的品质特点,同时与云南其他产区咖啡及国外咖啡进行对比。结果表明,不同产地普洱咖啡水分、灰分、粗纤维和水浸出物含量存在显著差异(P<0.05);与云南其他产区咖啡和国外咖啡相比,普洱咖啡蛋白质含量较高,灰分、总酸、粗纤维含量较低;有71%的普洱咖啡杯测分数到达精品咖啡标准要求,有6个普洱咖啡样品与世界著名精品咖啡聚在一类,说明小区域内环境种植的普洱咖啡可以和世界著名精品咖啡相媲美。

关键词：普洱咖啡内含成分杯测分数国家地理标志产品

Robust online temperature estimation of a membrane-wall gasifier

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Chinese Journal of Chemical Engineering 2020年第2期28卷 556-565页

作者： Jianliang Xu Qinfeng Liang Zhenghua Dai Xiaolei Guo haifeng liu Xin Gong Shanghai Engineering Research Center of Coal Gasification East China University of Science and TechnologyShanghai 200237China

The gasifier temperature is a key parameter in the operation of a slag-tapping entrained-flow ***,there is no effective method for measuring the operating temperature of a membrane-wall-lined *** this study,a novel robust method for estimation of the online temperature was developed for a membrane-wall gasifier and applied in an industrial SE *** industrial test results show that the method can estimate the gasifier temperature within 0.04 s,and its value can be reliably *** on the combination of bench-scale gasifier validation,commercial-scale gasifier operation experience,and the comparison of different simulation methods,the proposed method is accurate and reliable for measuring the operating temperature of a membrane-wall-lined gasifier.

关键词： Coal Gasification Temperature estimation Slag Membrane wall