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Study on Segmented Reflector Lamp Design Based on Error Analysis

厦门大学学报（自然科学版） 2002年第S1期41卷 143-144页

作者： liu hong, yuan ju-long (College of Mechanical & Electronical Engineering, Zhejiang University of Technology, Hangzhou 310014, China)

This paper discusses the basic principle and design m ethod for light distribution of car lamp, introduces an important development: h igh efficient and flexible car lamp with reflecting light distribution-segmente d reflector (multi-patch) car lamp, and puts out a design method for segmented reflector based on error analysis. Unlike classical car lamp with refractive lig ht distribution, the method of reflecting light distribution gives car lamp desi gn more flexibility. In the case of guarantying the lightness of car lamp and sa tisfying the standard demand for the light distribution, the design of the exter ior of the car lamp has more freedom. The high gradient of car lamp is more suit able for the demand of streamline of the car exterior. The shape of segmented re flector obtained by theory calculating of car lamp reflecting light distribution is only an ideal shape, which usually has considerable differences with the fin al shape and will influences light distribution. There exist difference between the calculated reflector and manufactured reflector. Owing to light reflecting c haracter, the small diversification of the reflector will reduce the big diver sification of the light distribution shape on light distribution screen in 25 -meter place, so light distribution quality can’t be ensured. To ensure the re flector by light distribution calculation accordance to reflector by practical m anufacture, the error effect of surface shape must be reasonably considered name ly the error effect of manufacture tache. The paper establishes error-analyzing model for segmented reflector according to the analysis of error of making proc ess for segmented reflector. Based on this error-analyzing model and by use of the analyzing software developed for segmented reflector light distribution, it could reasonably consider reflector errors made by manufacturing, such as reflec tor surface spray-painting and plating aluminum, which could give out shapes of reflector patches fo

关键词： car lamp design light distribution segmented surface reflector

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Visualization Simulations for Cold Press Die

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厦门大学学报（自然科学版） 2002年第S1期41卷 31-32页

作者： liu hong, yuan ju-long, JIN Jie (College of Mechanical & Electronical Engineering, Zhejiang University of Technology, Hangzhou 310014, China)

Pressing process is a manufacturing method that obtained work piece with certain dimension, shape and capability through die forcing roughcast to produce plastic deformation or separate. This paper focuses on the key problems of visualization simulation in pressing die. The final aim is that numerical simulation system can simulate the process of processing forming technique, which can supply some necessary and accurate key parameters for die design. The detail description of mechanical characteristic and key technique of sheet forming technique is discussed. Pressing forming method is one of the most important forming techniques of metal forming, which has special mechanical characteristics. The character of sheet pressing forming is that the deformation of thickness direction is very small in contrast to other directions. The deformation mode of sheet forming mainly has the following kinds: bi-directional stretch, plane stress, stretches, depths extend, bending and counter-bending. The essence of press forming is the transferring course that the transferring region of rough comes to deformation by outside force, which is main researching principle in forming and the transferring field. The analysis of pressing forming course, disclose the feature of stress-strain and their changing rule, then pressing process and forming parameters could be obtained. So the states of force and deformation of transferring region is key to determine character about the varieties of pressing transferring. The paper analyzes these factors, which may influence forming precision in pressing process. In traditional methods, some key parameter such as spring-back, bending radius for die design are calculated by experience formula or select from data table. The paper brings forward the calculation methods of key parameter in the case of drawing finite element method and numerical simulation into pressing die design. In order to calculate the value of key parameters based on data supplied b

关键词： cold press die visualization simulating

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Difluoromethyl phenoxathiinium salt: A new general and versatile difluoromethylating reagent with divergent ·CF_(2)H, CF_(2)H^(+), and :CF_(2) reactivities

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Science China Chemistry 2024年第3期67卷 953-962页

作者： yuan-Qing Gu hong-Xin long Dan-Dan Zhang Mei-Feng Ruan Guo-Kai liu School of Pharmacy Shenzhen University Medical SchoolShenzhen UniversityShenzhen 518055China

Development of practical and versatile electrophilic difluoromethylating reagent is still a grand challenge so far due to its inherent instability or low ***,we report the design and synthesis of difluoromethyl phenoxathiinium tetrafluoroborate(PT-CF_(2)H^(+)BF_(4)^(-)) as a novel difluoromethylating reagent,which proves to be a bench-stable,general,powerful and versatile reagent with divergent·CF_(2)H,CF_(2)H^(+),and:CF_(2) *** use of this reagent,we demonstrated a vast array of difluoromethyl radical transfer reactions via diverse pathways involving photocatalyst-free visible-light induction,visible-light photoredox catalysis and visible-light mediation single electron transfer of EDA ***,the green and highly effective CF_(2)H^(+) and:CF_(2) transfer reactions were also readily accomplished.

关键词： difluoromethyl phenoxathiinium salt versatile difluoromethylating reagent difluoromethyl radical difluoromthyl cation difluorocarbene

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Intense and Superflat White Laser with 700-nm 3-dB Bandwidth and 1-mJ Pulse Energy Enabling Single-Shot Subpicosecond Pulse Laser Spectroscopy

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Research 2024年第2期6卷 319-327页

作者： Lihong hong Haiyao Yang Liqiang liu Mingzhou Li yuanyuan liu Baoqin Chen Huakang Yu Wenbo ju Zhi-yuan Li School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510641China State Key Laboratory of Luminescent Materials and Devices South China University of TechnologyGuangzhou 510640China

An optical spectrometer is a basic spectral instrument that probes microscopic physical and chemical properties of macroscopic objects but generally suffers from difficulty in broadband time-resolved *** this work,we report the creation of ultrabroadband white-light laser with a 3-dB bandwidth covering 385 to 1,080 nm,pulse energy of 1.07 mJ,and pulse duration of several hundred femtoseconds by passing 3-mJ pulse energy,50-fs pulse duration Ti:Sapphire pulse laser through a cascaded fused silica plate and chirped periodically poled lithium niobate *** utilize this unprecedented superflat,ultrabroadband,and intense femtosecond laser light source to build a single-shot(i.e.,single-pulse)subpicosecond pulse laser ultraviolet-visible-near-infrared spectrometer and successfully measure various atomic and molecular absorption *** single-shot ultrafast spectrometer may open up a frontier to monitor simultaneously the ultrafast dynamics of multiple physical and chemical processes in various microscopic systems.

关键词： Pulse utilize frontier

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Tunable single emitter-cavity coupling strength through waveguide-assisted energy quantum transfer

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Light(Science & Applications) 2024年第9期13卷 1779-1788页

作者： yuan liu hongwei Zhou Linhan Lin hong-Bo Sun Department of Precision Instrument State Key Laboratory of Precision Measurement Technology and InstrumentsTsinghua UniversityBeijing 100084China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China

The emitter-cavity strong coupling manifests crucial significance for exploiting quantum technology,especially in the scale of individual ***,due to the small light-matter interaction cross-section,the single emitter-cavity strong coupling has been limited by its harsh requirement on the quality factor of the cavity and the local density of optical ***,we present a strategy termed waveguide-assisted energy quantum transfer(WEQT)to improve the single emitter-cavity coupling strength by extending the interaction *** ancillary emitters are optically linked by a waveguide,providing an indirect coupling channel to transfer the energy quantum between target emitter and *** enhancement factor of coupling strength eg=g>10 can be easily achieved,which dramatically release the rigorous design of *** an extension of concept,we further show that the ancillae can be used as controlling bits for a photon gate,opening up new degrees of freedom in quantum manipulation.

关键词： quantum coupling transfer

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Enhanced Grain Refining Effect of Mg–Zr Master Alloy on Magnesium Alloys via a Synergistic Strategy Involving Heterogeneous Nucleation and Solute‑Driven Growth Restriction

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1354-1366页

作者： Gang Zeng hong liu Jing‑Peng Xiong Jian‑long Li Yong liu Key Laboratory of Lightweight and High Strength Structural Materials of Jiangxi Province School of Advanced ManufacturingNanchang UniversityNanchang 330031China

Zirconium(Zr)emerges as the most effective grain refiner for magnesium(Mg)alloys incorporating ***,Zr is introduced in the form of an Mg–Zr master ***,within Mg–Zr master alloys,Zr predominantly exists in a particle form,which tends to aggregate due to attractive van der Waals *** clustered Zr is prone to settling,thereby reducing its refining impact on Mg *** this work,a combined pretreatment process for Mg–Zr master alloys was proposed,encompassing the introduction of a physical field to intervene the agglomeration of particle Zr and the employ of high-temperature dissolution and peritectic reactions to promote the solid solution of *** results demonstrate that the particle Zr within the pretreated Mg–Zr master alloy is effectively dispersed and refined,and greater solute Zr levels can be *** subsequent grain refinement ability was studied on a typical Mg–6Zn–0.6Zr(wt%)*** outcome highlights that an improvement in the grain refinement efficacy(32.4%)of Mg–Zr master alloys was obtained with a holding time of 60 *** pretreated Mg–Zr master alloy significantly augments the efficiency of grain refinement for Mg alloys through a synergistic strategy involving heterogeneous nucleation and solute-driven growth *** crucial factor in achieving effective grain refinement of Zr in Mg alloys lies in regulating the presence and morphology of Zr in the Mg–Zr master alloy,distinguishing between particle Zr and solute *** study introduces a novel method for developing more efficient Mg–Zr refiners.

关键词： Magnesium alloy Mg-Zr master alloy Grain refinement Heterogeneous nucleation Solute-driven growth restriction Synergistic strategy

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A Cauchy integral formula for(p,q)-monogenic functions withα-weight

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 545-553页

作者： GAO long DU Xiao-jing liu Yue XIE Yong-hong School of Mathematical Sciences Hebei Normal UniversityShijiazhuang 050024China

Firstly,some properties for(p,q)-monogenic functions withα-weight in Clifford analysis are ***,the Cauchy-Pompeiu formula is ***,the Cauchy integral formula and the Cauchy integral theorem for(p,q)-monogenic function... 详细信息

关键词： (p q)-monogenic functions with-weight Cauchy-Pompeiu formula Cauchy integral formula Cauchy integral theorem

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Electrochemical reconstruction: a new perspective on Sn metal-organic complex microbelts as robust anode for lithium storage

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Rare Metals 2024年第1期43卷 76-86页

作者： Jin-Ke Shen Nai-Teng Wu Li-yuan Wang Gang Jiang Dong-Lei Guo Jin Li Gui-long liu hong-Yu Mi Huan Pang Xian-Ming liu Key Laboratory of Function-oriented Porous Materials of Henan Province College of Chemistry and Chemical EngineeringLuoyang Normal UniversityLuoyang 471934China State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources School of Chemical Engineering and TechnologyXinjiang UniversityUrumqi 830046China School of Chemistry and Chemical Engineering Institute for Innovative Materials and EnergyYangzhou UniversityYangzhou 225009JiangsuChina

Tin-based materials with high theoretical capacity and suitable working voltage are ideal anode materials for lithium-ion batteries(LIBs). However, to overcome their shortcomings(volume expansion and inferior stability), the preparation processes are usually complicated and expensive. Herein, a tin-based metal-organic complex(tin 1,2-benzenedicarboxylic acid, Sn-BDC)with one-dimensional microbelt morphology is synthesized by a facile, rapid and low-cost co-precipitation method, and served as anode material for LIBs without any post-treatment. Sn-BDC exhibits a high reversible capacity with609/440 m Ah·g^(-1) at 50/2000 m A·g^(-1), and robust cycling stability of 856 m Ah·g^(-1) after 200 cycles at 200 m A·g^(-1),which are obviously superior to that of the Sn Ox/C counterparts. Moreover, an electrochemical reconstruction perspective on the lithium storage mechanism of Sn-BDC is proposed by systematic ex-situ characterizations. The reconstructed SnO_(2) replaces Sn-BDC and becomes the active material in the subsequent cycles. As the by-product of the lithiation reaction, the formed Li-based metal-organic complex(Li-BDC, wrapped around the reconstructed SnO_(2)) plays an important role in alleviating volume expansion and accelerating the charge transfer *** work is beneficial to design and construct the new electrode materials based on the electrochemical reconstruction for advanced LIBs.

关键词： Electrochemical reconstruction Metal-organic complex Anode Lithium storage mechanism Lithium-ion batteries

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Predicting submerged vegetation drag with a machine learning-based method

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Journal of Hydrodynamics 2024年第3期36卷 534-545页

作者： Meng-yang liu hong-wu Tang Sai-yu yuan Jing Yan College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China Key Laboratory of Hydrologic-Cycle and Hydrodynamic-System of Ministry of Water Resources Hohai UniversityNanjing210098China

Accurate estimation of the drag forces generated by vegetation stems is crucial for the comprehensive assessment of the impact of aquatic vegetation on hydrodynamic processes in aquatic *** coupling relationship between vegetation layer flow velocity and vegetation drag makes precise prediction of submerged vegetation drag forces particularly *** present study utilized published data on submerged vegetation drag force measurements and employed a genetic programming(GP)algorithm,a machine learning technique,to establish the connection between submerged vegetation drag forces and flow and vegetation *** using the bulk velocity,U,as the reference velocity scale to define the drag coefficient,C_(d),and stem Reynolds number,the GP runs revealed that the drag coefficient of submerged vegetation is related to submergence ratio(H^(*)),aspect ratio(d^(*)),blockage ratio(ψ^(*)),and vegetation density(λ).The relation between vegetation stem drag forces and flow velocity is implicitly embedded in the definition of C_(d).Comparisons with experimental drag force measurements indicate that using the bulk velocity as the reference velocity,as opposed to using the vegetation layer average velocity,U_(v),eliminates the need for complex iterative processes to estimate U_(v)and avoids introducing additional errors associated with U_(v)*** approach significantly enhances the model’s predictive capabilities and results in a simpler and more user-friendly formula expression.

关键词： Drag coefficient genetic programming algorithm submerged vegetation flow resistance cylinder array

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Track-Pattern-Based Characteristics of Extratropical Transitioning Tropical Cyclones in the Western North Pacific

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Advances in Atmospheric Sciences 2024年第6期41卷 1251-1263页

作者： hong HUANG Dan WU yuan WANG Zhen WANG Yu liu College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410000China No.31631 Army of PLA Huizhou 516000China School of Atmospheric Sciences and Key Laboratory of Mesoscale Severe Weather/Ministry of Education Nanjing 210023China No.93721 Army of PLA Shuozhou 038300China

Based on the Regional Specialized Meteorological Center(RSMC)Tokyo-Typhoon Center best-track data and the NCEP-NCAR reanalysis dataset,extratropical transitioning(ET)tropical cyclones(ETCs)over the western North Pacific(WNP)during 1951–2021 are classified into six clusters using the fuzzy c-means clustering method(FCM)according to their track *** characteristics of the six hard-clustered ETCs with the highest membership coefficient are *** tropical cyclones(TCs)that were assigned to clusters C2,C5,and C6 made landfall over eastern Asian countries,which severely threatened these *** landfalling TCs,93.2%completed their ET after landfall,whereas 39.8%of ETCs completed their transition within one *** frequency of ETCs over the WNP has decreased in the past four decades,wherein cluster C5 demonstrated a significant decrease on both interannual and interdecadal timescales with the expansion and intensification of the western Pacific subtropical high(WPSH).This large-scale circulation pattern is favorable for C2 and causes it to become the dominant track pattern,owning to it containing the largest number of intensifying ETCs among the six clusters,a number that has increased insignificantly over the past four *** surface roughness variation and three-dimensional background circulation led to C5 containing the maximum number of landfalling TCs and a minimum number of intensifying *** results will facilitate a better understanding of the spatiotemporal distributions of ET events and associated environment background fields,which will benefit the effective monitoring of these events over the WNP.

关键词： Western North Pacific tropical cyclone extratropical transition fuzzy c-means clustering method

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