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Science China(Information Sciences) 2023年第8期66卷 279-280页

作者： Bo HU Han WU Kan TIAN Houkun LIANG College of Electronics and Information Engineering Sichuan University

Continuous-wave(CW) tunable mid-infrared(MIR) laser sources are necessary for laser spectroscopy, remote sensing,and infrared imaging applications [1]. Generally, quantum cascaded lasers(QCLs) are mature MIR radiation sources with decent power. However, the tunning range of QCLs is limited to ten of cm-1. In contrast, difference-frequency generation(DFG) sources based on nonlinear optical crystals have advantages in broad wavelength tunability.

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Stability analysis of robotic longitudinal-torsional composite ultrasonic milling

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Chinese Journal of Aeronautics 2022年第8期35卷 249-264页

作者： Lianjun SUN Wenhe LIAO kan ZHENG Wei tian Jinshan LIU Jindan FENG School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China China Academy of Space Technology Beijing 100094China

Currently,industrial robots are considered as an alternative towards traditional machine tools.Especially for the large-scale parts milling,robotic flexibility and low cost make it possess the irreplaceability.However,the milling chatter caused by its weak rigidity hampers robotic application and promotion severely in aviation industry.Rotary ultrasonic milling(RUM)technology with one-dimensional axial vibration has been proven and approved on avoiding robotic chatter.Based on this,the research of project team demonstrates that longitudinal-torsional composite ultrasonic milling(CUM-LT)involving separation characteristic has a greater advantage than RUM in terms of chatter suppression.Thereby,the CUM-LT as a new means is applied to avoid processing vibration of robotic milling system.And its influence mechanism on stability improvement of weak stiffness processing system is clarified.Meanwhile,the approaches to strengthen separation effect are provided innovatively.Moreover,a new analysis method of robotic CUM-LT(RCUM-LT)stability is proposed on the basis of ultrasonic function angles.The simulation and experimental results indicate that compared with robotic RUM(RRUM),stability regions of separated RCUM-LT(SRCUM-LT)and unseparated RCUM-LT(URCUM-LT)are improved by 124.42%and39.20%,respectively.The addition of torsional ultrasonic energy has a wonderful effect on the milling chatter suppression of low stiffness robots.

关键词： Chatter suppression Industrial robots Longitudinal-torsional composite Rotary ultrasonic milling Stability analysis

Simple,stable and efficient nonlinear pulse compression through cascaded filamentation in air

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High Power Laser Science and Engineering 2023年第6期11卷 193-198页

作者： Tao Pu Kan TIAN Bo Hu Zhongjun Wan Linzhen He Xuemei Yang Han Wu Yang Li Weizhe Wang Houkun Liang College of Electronics and Information Engineering Sichuan UniversityChengduChina

Nonlinear compression has become an obligatory technique along with the development of ultrafast lasers in generating ultrashort pulses with narrow pulse widths and high peak power.In particular,techniques of nonlinear compression have experienced a rapid progress as ytterbium(Yb)-doped lasers with pulse widths in the range from hundreds of femtoseconds to a few picoseconds have become mainstream laser tools for both scientific and industrial applications.Here,we report a simple and stable nonlinear pulse compression technique with high efficiency through cascaded filamentation in air followed by dispersion compensation.Pulses at a center wavelength of 1040 nm with millijoule pulse energy and 160 fs pulse width from a high-power Yb:CaAlGdO_(4) regenerative amplifier are compressed to 32 fs,with only 2.4% loss from the filamentation process.The compressed pulse has a stable output power with a root-meansquare variation of 0.2% over 1 hour.

关键词： femtosecond pulse filamentation nonlinear compression

Neurotoxicity due to dimethylamine borane poisoning via skin absorption:a case report

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World Journal of Emergency Medicine 2022年第6期13卷 500-503页

作者： Guang-cai Yu Ya-qian Li tian-zi Jian Bao-tian kan Si-qi Cui Ping Han Xiang-dong Jian Department of Poisoning and Occupational Diseases Emergency MedicineQilu Hospital of Shandong UniversityCheeloo College of MedicineShandong UniversityJinan 250012China Shandong University of Traditional Chinese Medicine Jinan 250012China Department of Geriatric Medicine Qilu Hospital of Shandong UniversitySchool of NursingCheeloo College of MedicineShandong UniversityJinan 250012China School of Public Health Cheeloo College of MedicineShandong UniversityJinan 250012China

Dear editor,Dimethylamine borane(DMAB,CAS no.74-94-2),also called boron-dimethylamine complex,is a white crystalline solid.It has an amine odour under mild conditions.[1]As an excellent reducing agent,DMAB is widely used in the semiconductor industry,pharmaceutical manufacturing,[2]oligomer and polymer production,and hydrogen storage.[3]Acute DMAB exposure may cause eye or respiratory irritation,throat discomfort,vomiting,diarrhoea,and pulmonary oedema.[1,4]Isolated reports indicated that DMAB exposure causes acute cerebellar oedema and peripheral neuropathy.[1,5,6]Herein,we report a case of DMAB poisoning via dermal absorption in which the central and peripheral nervous systems were the primary sites of toxic injury.We highlight the use of brain magnetic resonance imaging(MRI)and electromyography(EMG)for evaluation after exposure.

关键词： conditions. absorption boron

Microstructure and Mechanical Properties of Al_2O_3/ZrO_2 Directionally Solidified Eutectic Ceramic Prepared by Laser 3D Printing

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Journal of Materials Science & Technology 2016年第4期32卷 320-325页

作者： Zhi Liu kan Song Bo Gao tian tian Haiou Yang Xin Lin Weidong Huang State Key Laboratory of Military Stomatology Department of Prosthodontics School of Stomatology Fourth Military Medical University State Key Laboratory of Solidification Processing Northwestern Polytechnical University

Directionally solidified eutectic ceramics such as Al2O3/ZrO2 are promising structural materials for ap- plications in harsh environment with an ultrahigh temperature. In this work, through adopting assistant heating laser 3D printing, Al2O3/ZrO2 eutectic samples were manufactured with suppressing the forma- tion of cracks. The dependence of the average rod spacing （λav） on the scanning rate （V） follows a relation with λavV0.5 = 1 μm1.5 s^-0.5. Typical eutectic microstructures, so-called complex regular, were analyzed with respect to its evolution with modulating the growth conditions. Formation mechanism of the solidifi- cation defect, shrinkage porosity, was discussed and the defect is found to be significantly suppressed by optimizing the solidification parameters. The maximum hardness and fracture toughness are mea- sured to he 16.7 GPa and 4.5 MPa m1/2, respectively. The interplay between the propagation of cracks and the Al2O3/ZrO2 interface is discussed.

关键词： Al2O3 ZrO2 Eutectic Solidification

Impact of Temperature on Mortality in Three Major Chinese Cities

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Biomedical and Environmental Sciences 2014年第7期27卷 485-494页

作者： ZHANG Jing LI tian tian TAN Jian Guo HUANG Cun Rui kan Hai Dong School of Public Health Key Laboratory of Public Health Safety of Ministry of EducationFudan University Institute of Environmental Health and Related Product Safety China Center for Disease Control and Prevention Shanghai Key Laboratory of Meteorology and Health Shanghai Meteorological InstituteSMB School of Public Health and Institute of Health and Biomedical Innovation Queensland University of Technology Research Institute for the Changing Global Environment and Fudan Tyndall Centre Fudan University Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Fudan University

Objective To study the relation between temperature and mortality by estimating the temperature-related mortality in Beijing, Shanghai, and Guangzhou. Methods Data of daily mortality, weather and air pollution in the three cities were collected. A distributed lag nonlinear model was established and used in analyzing the effects of temperature on mortality. Current and future net temperature-related mortality was estimated. Results The association between temperature and mortality was J-shaped, with an increased death risk of both hot and cold temperature in these cities. The effects of cold temperature on health lasted longer than those of hot temperature. The projected temperature-related mortality increased with the decreased cold-related mortality. The mortality was higher in Guangzhou than in Beijing and Shanghai. Conclusion The impact of temperature on health varies in the 3 cities of China, which may have implications for climate policy making in China.

关键词： Climate change Temperature Mortality Time-series

Hybrid windowed networks for on-the-fly Doppler broadening in RMC code

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Nuclear Science and Techniques 2021年第6期32卷 70-82页

作者： tian-Yi Huang Ze-Guang Li kan Wang Xiao-Yu Guo Jin-Gang Liang Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China Department of Engineering Physics Tsinghua UniversityBeijing 100084China

On-the-fly Doppler broadening of cross sections is important in Monte Carlo simulations,particularly in Monte Carlo neutronics-thermal hydraulics coupling simulations.Methods such as Target Motion Sampling(TMS)and windowed multipole as well as a method based on regression models have been developed to solve this problem.However,these methods have limitations such as the need for a cross section in an ACE format at a given temperature or a limited application energy range.In this study,a new on-the-fly Doppler broadening method based on a Back Propagation(BP)neural network,called hybrid windowed networks(HWN),is proposed to resolve the resonance energy range.In the HWN method,the resolved resonance energy range is divided into windows to guarantee an even distribution of resonance peaks.BP networks with specially designed structures and training parameters are trained to evaluate the cross section at a base temperature and the broadening coefficient.The HWN method is implemented in the Reactor Monte Carlo(RMC)code,and the microscopic cross sections and macroscopic results are compared.The results show that the HWN method can reduce the memory requirement for cross-sectional data by approximately 65%;moreover,it can generate keff,power distribution,and energy spectrum results with acceptable accuracy and a limited increase in the calculation time.The feasibility and effectiveness of the proposed HWN method are thus demonstrated.

关键词： Monte Carlo method Reactor Monte Carlo(RMC) On-the-fly Doppler broadening BP network

Explosion characteristics of aluminum-based activated fuels containing fluorine

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Defence Technology（防务技术） 2023年第2期20卷 34-43页

作者： Jin-tao Xu Lei Huang Hai-peng Jiang tian-jiao Zhang Feng-qi Zhao Jian-kan Zhang Wei Gao State Key Laboratory of Fine Chemicals Department of Chemical Machinery and Safety EngineeringDalian University of TechnologyDalian116024China Beijing Institute of Aerospace Testing Technology Beijing100074China Science and Technology on Combustion and Explosion Laboratory Xi'an Modern Chemistry Research InstituteXi'an710065China

Measuring the dust explosion characteristics of aluminum-based activated fuels was a prerequisite for developing effective prevention and control measures.In this paper,ignition sensitivity,flame propagation behaviors and explosion severity of aluminum/polytetrafluoroethylene(Al/PTFE)compositions including 2 PT(2.80 wt.%F),4 PT(7.18 wt.%F)and 8 PT(11.90 wt.%F)were studied.When the content of F increased from 2.80 wt.%to 11.90 wt.%,the minimum explosive concentration MEC decreased from380 g/m^(3)to 140 g/m^(3),due to the dual effects of increased internal active aluminum and enhanced reactivity.The average flame propagation velocities increased as the percentage of F increased.The maximum explosion pressure Pmof 500 g/m3aluminum-based activated fuels increased from 247 k Pa to299 kPa.Scanning electron microscopy demonstrated that with the increase of PTFE content,the reaction was more complete.On this basis,the explosion mechanism of aluminum-based activated fuels was revealed.

关键词： Aluminum-based activated fuels Ignition sensitivity Flame propagation Explosion severity Explosion mechanism

Excessive gestational weight gain in early pregnancy and insufficient gestational weight gain in middle pregnancy increased risk of gestational diabetes mellitus

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Chinese Medical Journal 2022年第9期135卷 1057-1063页

作者： Aiqi Yin Fuying tian Xiaoxia Wu Yixuan Chen kan Liu Jianing Tong Xiaonian Guan Huafan Zhang Linlin Wu Jianmin Niu Department of Obsetics Shenchen Matemity and Chid Helthare HoptalThe First School of Cinial MedicneSouthem Medcal UnierityShenzhenGuangdong 518028China

Background:Gestational weight gain(GWG)is associated with the risk of gestational diabetes mellitus(GDM).However,the effect of weight gain in different trimesters on the risk of GDM is unclear.This study aimed to evaluate the effect of GWG on GDM during different trimesters.Methods:A birth cohort study was conducted from 2017 to 2020 in Shenzhen,China.In total,51,205 participants were included comprising two models(early pregnancy model and middle pregnancy model).Gestational weight(kg)was measured at each prenatal clinical visit using a standardized weight scale.Logistic regression analysis was used to assess the risk of GDM.Interaction analysis and mediation effect analysis were performed in the middle pregnancy model.Results:In the early pregnancy model,the risk of GDM was 0.858 times lower(95%confidence interval[CI]:0.786,0.937)with insufficient GWG(iGWG)and 1.201 times higher(95%CI:1.097,1.316)with excessive GWG after adjustment.In the middle pregnancy model,the risk of GDM associated with iGWG increased 1.595 times(95%CI:1.418,1.794)after adjustment;for excessive GWG,no significant difference was found(P=0.223).Interaction analysis showed no interaction between GWG in early pregnancy(GWG-E)and GWG in middle pregnancy(GWG-M)(F=1.268;P=0.280).The mediation effect analysis indicated that GWG-M plays a partial mediating role,with an effect proportion of 14.9%.Conclusions:eGWG-E and iGWG-M are associated with an increased risk of GDM.Strict control of weight gain in early pregnancy is needed,and sufficient nutrition should be provided in middle pregnancy.

关键词： Gestational diabetes mellitus Gestational weight gain Early pregnancy Middle pregnancy

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Journal of Genetics and Genomics 2017年第1期44卷 63-66页

作者： BO Yuan tian-lin Cheng kan Yang Xu Zhang Zilong Qiu Institute of Neuroscience Key Laboratory of Primate Neurobiology CAS Center for Excellence in Brain Science and Intelligence Technology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China Institute of Chemistry and Bioengineering Donghua University Shanghai 200051 China Shanghai Clinical Research Center Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China

Methyl-CpG binding protein 2 （MeCP2） has a crucial role in transcriptional regulation and neural development （Ausi6 et al., 2014）. Loss of function mutations of MECP2 in human lead to Rett syndrome （RTT）, a severe neurodevelopmental disorders （Amir et al., 1999）, whereas individuals with the chromosomal duplications containing the MECP2 locus showed severe autism-like symptoms （Ramocki et al., 2009）.

关键词： FGF Autism-related protein MeCP2 regulates FGF13 expression and emotional behaviors microRNAs