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High-sensitive terahertz detection by parametric up-conversion using nanosecond pulsed laser

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Chinese Physics B 2022年第2期31卷 336-341页

作者： yuye Wang Gang Nie Changhao Hu Kai Chen Chao Yan Bin Wu Junfeng Zhu Degang xu Jianquan Yao Institute of Laser and Optoelectronics School of Precision Instruments and Optoelectronics EngineeringTianjin UniversityTianjin 300072China Key Laboratory of Optoelectronic Information Technology(Ministry of Education) Tianjin UniversityTianjin 300072China Science and Technology on Electronic Test&Measurement Laboratory Qingdao 266555China

A high-sensitive terahertz detector operating at room temperature was demonstrated based on parametric upconversion.A nanosecond 1064-nm Nd:YAG laser was used to pump the parametric up-conversion detector and the upconversion from terahertz wave to NIR laser was realized in a lithium niobate *** minimum detectable terahertz energy of 9 p J was realized with the detection dynamic range of 54 d B,which was three orders of magnitude higher than that of commercial Golay *** detectable terahertz frequency range of the detection system was 0.90 Thz–1.83 ***,the effects of pump energy and effective gain length on the detection sensitivity were studied in *** results showed that higher pump energy and longer effective gain length are helpful for improving the detection sensitivity of parametric up-conversion detector.

关键词： terahertz wave high-sensitive detection room temperature operation parametric up-conversion

Energy scaling and extended tunability of a ring cavity terahertz parametric oscillator based on KTiOPO_(4) crystal

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Chinese Physics B 2018年第11期27卷 512-516页

作者： yuye Wang Yuchen Ren Degang xu Longhuang Yang Yixin He Ci Song Linyu Chen Changzhao Li Chao Yan Jianquan Yao Institute of Laser and Optoelectronics School of Precision Instruments and Optoelectronic EngineeringTianjin UniversityTianjin 300072China Key Laboratory of Optoelectronic Information Science and Technology(Ministry of Education) Tianjin UniversityTianjin 300072China College of Computer and Information Engineering Tianjin Agricultural UniversityTianjin 300384China

A wide terahertz tuning range from 0.96 THz to 7.01 THz has been demonstrated based on ring-cavity THz wave parametric oscillator with a KTiOPO_(4)(KTP)*** tuning range was observed intermittently from 0.96 THz to 1.87 THz,from 3.04 THz to 3.33 THz,from 4.17 THz to 4.48 THz,from 4.78 THz to 4.97 THz,from 5.125 THz to 5.168 THz,from5.44 THz to 5.97 THz,and from 6.74 THz to 7.01 *** dual-Stokes wavelengths resonance phenomena were observed in some certain tuning angle *** the theoretical analysis of the dispersion curve of the KTP crystal,the intermittent THz wave tuning range and dual-wavelength Stokes waves operation during angle tuning process were *** theoretical analysis was in good agreement with the experiment *** maximum THz output voltage detected by Golay cell was 1.7 V at 5.7 THz under the pump energy of 210 mJ,corresponding to the THz wave output energy of5.47μJ and conversion efficiency of 2.6×10^(-5).

关键词： terahertz parametric oscillator KTiOPO_(4)crystal extended tunability energy scaling

爆炸冲击作用下预制节段拼装桥墩的动态响应与损伤分析

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爆炸与冲击 2019年第3期39卷 141-148页

作者：杨旭张于晔张宁南京理工大学土木工程系江苏南京210094

为研究爆炸冲击作用下预制节段拼装桥墩的动态响应与损伤,采用ANSYS/LS-DYNA建立圆形截面预制节段拼装桥墩受爆的三维实体分离式模型。通过与已有实验结果的对比分析,验证了该模拟方法的可靠性。基于该模型,研究了爆炸冲击作用下节段长... 详细信息

为研究爆炸冲击作用下预制节段拼装桥墩的动态响应与损伤,采用ANSYS/LS-DYNA建立圆形截面预制节段拼装桥墩受爆的三维实体分离式模型。通过与已有实验结果的对比分析,验证了该模拟方法的可靠性。基于该模型,研究了爆炸冲击作用下节段长细比、初始预应力水平及桥墩体系对圆形截面预制拼装桥墩动态响应与损伤的影响规律。结果表明:减小节段长细比使墩身由剪切破坏逐渐变为节段间相对位移,并减小墩身的整体侧向位移;提高初始预应力水平可以在一定程度上提高桥墩的抗爆性能;爆炸冲击作用下混合体系桥墩兼具完全节段和整体现浇桥墩的破坏特征。

关键词：节段拼装桥墩爆炸响应抗爆性能损伤分析

节段拼装桥墩在爆炸冲击作用下的破坏模式与损伤评估研究

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振动与冲击 2020年第23期39卷 225-233页

作者：张于晔杨旭冯君南京理工大学土木工程系南京210094 南京理工大学瞬态物理国家重点实验室南京210094

为研究爆炸冲击作用下节段拼装桥墩的破坏模式和损伤评估方法,采用ANSYS/LS-DYNA建立方形截面整体式桥墩和节段拼装桥墩受爆的三维实体分离式模型。基于与爆炸试验结果的对比分析,验证该模拟方法的可靠性。通过改变爆炸TNT当量和爆炸距... 详细信息

为研究爆炸冲击作用下节段拼装桥墩的破坏模式和损伤评估方法,采用ANSYS/LS-DYNA建立方形截面整体式桥墩和节段拼装桥墩受爆的三维实体分离式模型。基于与爆炸试验结果的对比分析,验证该模拟方法的可靠性。通过改变爆炸TNT当量和爆炸距离,对比分析了不同超压作用下整体式桥墩与节段拼装桥墩的应力变化、破坏模式与损伤机理,并提出结合截面损伤与墩身侧移的桥墩受爆损伤评估方法。结果表明:在爆炸冲击与恒载共同作用下,整体式桥墩主要呈现剪切破坏与弯剪破坏,节段拼装桥墩主要呈现剪切破坏与局部破坏;在不同比例距离的爆炸冲击作用下,桥墩的损伤均可分为完全弹性、部分弹性及失去弹性等三种状态;节段拼装桥墩在受到爆炸冲击作用后,墩身节段间产生较大相对转角和位移,进而导致节段截面削弱和墩身侧移;两种体系桥墩均可采用截面削弱与墩身侧移相结合的方法,进行爆炸损伤的定量评估。

关键词：节段拼装桥墩破坏机理抗爆性能损伤评估

Water Molecule-Triggered Anisotropic Deformation of Carbon Nitride Nanoribbons Enabling Contactless Respiratory Inspection

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CCS Chemistry 2021年第6期3卷 1615-1625页

作者： yuye Zhang Yongxiu Song Yanfei Shen Kaiyang Chen Qing Zhou Yanqin Lv Hong Yang Ensheng xu Songqin Liu Lei Liu Yuanjian Zhang Jiangsu Engineering Laboratory of Smart Carbon-Rich Materials and Device Jiangsu Provincial Hi-Tech Key Laboratory for Biomedical ResearchSchool of Chemistry and Chemical EngineeringMedical SchoolSoutheast UniversityNanjing 211189 Institute for Advanced Materials School of Material Science and TechnologyJiangsu UniversityZhenjiang 212013

The exploitation of the interaction between nanostructured matter and small molecules,such as H_(2)O at interfaces via dynamic hydrogen bonding,is essentially the key for smart,responsive nanodevices but remains ***,the authors report that the carbon nitride nanoribbons(CNNRs)with an anisotropic intraplanar and interplanar molecular arrangement underwent a deformation by H_(2)O *** experiments of bulk samples and single nanoribbons disclosed that the reversible formation of a hydrogen-bonded H_(2)O adsorption layer was the source of the CNNRs deformation,reminiscent of the hydration-triggered twist of natural bean pods in ***,CNNRs had a more balanced H_(2)O affinity,enabling a superior response and recovery *** coupling with carbon nanotubes,the authors also converted the deformation of CNNRs into more straightforward electrical readouts with record-fast response *** applied to capture fluctuations in humidity in real-time respiration,a higher detection sensitivity was obtained in a contactless mode,which compared favorably with the clinical breath-testing *** the carbon nitride family with various C/N ratios,surface properties,and topography,this finding that CNNRs are an outstanding H_(2)O transducer would significantly pave the way for the H_(2)O-triggered smart devices in broad prospective applications.

关键词： polymeric carbon nitride anisotropic deformation surface properties water molecules transducer contactless respiratory monitoring

Calyciphylline A-型虎皮楠生物碱himalensine A的全合成研究进展

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科学通报 2021年第25期66卷 3241-3250页

作者：胡晶平陈雨叶徐晶哈尔滨工业大学化工与化学学院哈尔滨150001 南方科技大学化学系深圳格拉布斯研究院深圳518055 广东省催化化学重点实验室深圳518055

虎皮楠生物碱自从1909年被首次分离报道至今,已有300多个已知家族成员.它们具有广泛的生物活性以及复杂多变的多环骨架结构,其独特的氮杂笼状稠环结构以及骨架中包含季碳中心的多个手性中心使得其合成极具挑战性.在虎皮楠生物碱的众多... 详细信息

虎皮楠生物碱自从1909年被首次分离报道至今,已有300多个已知家族成员.它们具有广泛的生物活性以及复杂多变的多环骨架结构,其独特的氮杂笼状稠环结构以及骨架中包含季碳中心的多个手性中心使得其合成极具挑战性.在虎皮楠生物碱的众多家族中,含有20多个成员的calyciphylline A-型虎皮楠生物碱是具有代表性的家族之一,而himalensine A则是calyciphylline A-型虎皮楠生物碱的代表性成员之一.该分子被岳建民课题组分离报道以来受到了众多合成化学家的关注,迄今已有多篇合成研究与全合成工作报道.本文主要介绍关于calyciphylline A-型虎皮楠生物碱himalensine A近期的全合成研究进展.这些工作为虎皮楠生物碱的全合成研究贡献了宝贵的经验,并展示了许多开拓性的思路.

关键词：虎皮楠生物碱天然产物全合成 calyciphylline A himalensine A

Study on the Deformation Behavior of Mg-Gd-Y-Zn-Mn Wrought Magnesium Alloys by Visco-plastic Self-consistent Modeling

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上海航天（中英文） 2022年第1期39卷 77-83,136页

作者： WANG yuye ZHANG Junfa WANG Shiwei KANG Jing MENG Jiajie WANG Yanbo xu Yuling ZHOU Haitao Shanghai Spaceflight Precision Machinery Institute Shanghai 201600China Beijing Institute of Space Long March Vehicle Beijing 100076China

The plastic deformation behavior of new Mg-Gd-Y-Zn-Mn magnesium alloys gains great necessity to clarify and understand the mechanism deeply. In the present work,the tensile mechanical property test and visco-plastic self-consistent (VPSC) model are used to investigate the activities of deformation modes of VW84M and VW94M magnesium alloys during the tensile deformation. The results show that the mechanical properties of the above extruded alloys are similar but VW94M has higher strength than VW84M after the same aging process. Compared with the extruded alloys,the as-aged alloys have significantly higher activation of pyramidal slip at the later stage of plastic deformation. In addition,the as-aged VW94M alloy with higher strength has the largest activity of pyramidal slip. In summary,the addition of Gd increases the critical resolved shear stress (CRSS)in each slip system of VW94M,while the increase in the strength and the decrease in the elongation of as-aged alloys are associated with the significant activation of pyramidal slip.

关键词： Mg-RE alloy wrought magnesium alloy visco-plastic self-consistent(VPSC)model deformation behavior

Enhanced picosecond terahertz wave generation based on cascade effects in a terahertz parametric generator

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Chinese Physics B 2024年第8期33卷 271-275页

作者：张敬喜王与烨徐炳烽陈锴刘紫鲲马鸿儒徐德刚姚建铨 School of Precision Instruments and Optoelectronics Engineering Tianjin UniversityTianjin 300072China Key Laboratory of Optoelectronic Information Technology(Ministry of Education) Tianjin UniversityTianjin 300072China

Enhanced terahertz wave generation via a Stokes cascade process has been demonstrated using picosecond pulse pumped terahertz parametric generation at 1 kHz repetition *** cascade saturation of terahertz output was observed,and the corresponding cascade-Stokes spectra were *** maximum terahertz wave average power was 22μW under a pump power of 30 W,whereas the maximum power conversion efficiency was 8×10^(-7)under a pump power of 21 *** THz power fluctuation was measured to be about 1%in 20 *** THz parametric source with a relatively stable output is suitable for a variety of practical applications.

关键词： terahertz parametric generation stimulated polariton cascade effect CLN crystal

Electroacupuncture targeting the immune system to alleviate sepsis

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Acupuncture and Herbal Medicine 2024年第1期4卷 56-67页

作者： Mengyue Fang yuye Lan Man Li Chennan Li Bin xu Yan Ma Sulukkana Noiprasert Xianghong Jing Lingling Yu Tongji Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina School of Basic Medicine Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Key Laboratory of Integrated Acupuncture and Medicine Research of Ministry of Education Nanjing University of Chinese MedicineNanjingChina Wuhan No.1 Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina School of Integrative Medicine Mae Fah Luang UniversityChiangraiThailand Institute of Acupuncture and Moxibustion China Academy of Chinese Medical SciencesBeijingChina Institute of Integrated Traditional Chinese and Western Medicine Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina

Sepsis is a life-threatening inflammatory syndrome with high morbidity and mortality ***,options for sepsis are still limited to general treatment in intensive care units(ICUs),and effective therapies that improve sepsis survival are *** disturbances play a vital role in the pathology of sepsis and are associated with protracted inflammation,susceptibility to infections,and ***,many investigators have focused on the potential benefits of immunomodulation therapy for ***(EA)has been practiced in clinics for many years and has shown advantages in treating infectious *** the last few decades,our understanding of the efficacy and mechanisms of EA in sepsis has undergone considerable *** searched the literature regarding“CNKI,Wan Fang Data,VIP Database,PubMed,and Ingenta Connect”from 2010 to 2023,using the keywords“sepsis”“septic”and“electroacupuncture”and 336 sources were ***,we included 82 studies that targeted the immune system to determine EA’s anti-inflammatory and immunomodulatory effects on *** this review,we found that EA has clinical benefits in relieving septic inflammation,improving immune function,and attenuating related multi-organ injury through several mechanisms,such as activation of the cholinergic anti-inflammatory pathway(CAP),vagaladrenal axis,inhibition of the nuclear factor Kappa-B(NF-κB)signaling pathway,signal transducers and activators of transcription(STAT)signaling pathway,and improvement of immune cell ***,EA may be a promising complementary therapy for sepsis *** also expect these data will contribute to further studies on EA in sepsis.

关键词： Cholinergic anti-inflammatory pathway Electroacupuncture Nuclear factor Kappa-B Sepsis Signal transducers and activators of transcription Vagal-adrenal axis