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Distributed Vibration Sensor With Laser Phase-Noise Immunity by Phase-Extraction φ-OTDR

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Photonic Sensors 2019年第3期9卷 223-229页

作者： Yuying SHAO huanhuan liu Peng PENG Fufei PANG Guoqin YU Zhen CHEN Na CHEN Tingyun WANG State Grid Shanghai Municipal Electric Power Company Shanghai 200072 China Key laboratory of Specialty Fiber Optics and Optical Access Networks Joint International Research Laboratory of Specialty Fiber Optics and Advanced Communication Shanghai Institute for Advanced Communication and Data Science Shanghai University Shanghai 200444 China

We have demonstrated a distributed vibration sensor based on phase-sensitive optical time-domain reflectometer (φ-OTDR) system exhibiting immunity to the laser phase noise. Two laser sources with different linewidth and phase noise levels are used in the φ-OTDR system, respectively. Based on the phase noise power spectrum density of both lasers, the laser phase is almost unchanged during an extremely short period of time, hence, the impact of phase noise can be suppressed effectively through phase difference between the Rayleigh scattered light from two adjacent sections of the fiber which define the gauge length. Based on the phase difference method, the external vibration can be located accurately at 41.01 km by the(φ-OTDR system incorporating these two lasers. Meanwhile, the average signal-to-noise ratio (SNR) of the retrieved vibration signal by using Laser I is found to be -37.7 dB, which is comparable to that of -37.5 dB by using Laser II although the linewidth and the phase noise level of the two lasers are distinct. The obtained results indicate that the phase difference method can enhance the performance of(φ-OTDR system with laser phase-noise immunity for distributed vibration sensing, showing potential application in oil-gas pipeline monitoring, perimeter security, and other fields.

关键词： Distributed vibration sensing optical time domain reflectometer fiber sensor phase noise

Photoluminescent biodegradable polyorganophosphazene: A promising scaffold material for in vivo application to promote bone regeneration

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Bioactive Materials 2020年第1期5卷 102-109页

作者： Yiqian Huang Zhaohui Huang huanhuan liu Xu Zhang Qing Cai Xiaoping Yang State Key Laboratory of Organic-Inorganic Composites Beijing Laboratory of Biomedical MaterialsBeijing University of Chemical TechnologyBeijing100029China Department of Endodontics School and Hospital of StomatologyTianjin Medical UniversityTianjin300070China

Tissue engineering scaffolds made of conventional aliphatic polyesters are inherently non-fluorescent,which results in their in vivo degradation hard to be *** biodegradable polyorganophosphazenes(PPOPs)are synthesized by introducing fluorophores onto the polyphosphazene backbone via nucleophilic substitution *** this study,a fluorophore(termed as TPCA),derived from citric acid and 2-aminoethanethiol,was co-substituted with alanine ethyl ester onto the polyphosphazene backbone to obtain a photoluminescent biodegradable POPP(termed as PTA).The scaffolds made of PTA demonstrated non-cytotoxicity and cell affinity,particularly,capacity in promoting osteogenic differentiation of bone marrow mesenchymal stromal cells(BMSCs).In vivo evaluations using the rat calvarial defect model confirmed its strong potential in enhancing osteogenesis,more importantly,the in vivo degradation of the PTA scaffold could be monitored via its fluorescence intensity alongside implantation time.

关键词： Tissue regeneration Biodegradation Photoluminescent Polyorganophosphazene

基于SCF/C-kit信号通路探讨黄连解毒汤对脑出血急性期模型大鼠胃损伤的影响

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江苏中医药 2024年第4期56卷 71-76页

作者：王春燕兰雅文唐明高召凯张增刘欢欢孔晓璇李雯雯潘岳峰安朋朋山东中医药大学第一临床医学院山东济南250013 青岛市中医医院山东青岛266033 青岛大学第一临床医学院山东青岛266071

目的:观察黄连解毒汤对脑出血急性期模型大鼠胃损伤的干预作用,并从干细胞因子/酪氨酸激酶受体(SCF/C-kit)信号通路方面探索其作用机制。方法:选择健康SD雄性10周龄大鼠进行实验。取部分大鼠采用自体血注入法制作脑出血模型,将造模成功... 详细信息

目的:观察黄连解毒汤对脑出血急性期模型大鼠胃损伤的干预作用,并从干细胞因子/酪氨酸激酶受体(SCF/C-kit)信号通路方面探索其作用机制。方法:选择健康SD雄性10周龄大鼠进行实验。取部分大鼠采用自体血注入法制作脑出血模型,将造模成功的大鼠随机分为模型组、莫沙必利组和黄连解毒汤组,每组24只;另取24只大鼠仅进针不注入自体血,作为假手术组;另取24只常规饲养大鼠作为正常组。黄连解毒汤组大鼠予黄连解毒汤颗粒剂悬浊液54 mg/d灌胃,莫沙必利组大鼠予莫沙必利悬浊液0.27 mg/d灌胃,其余各组均灌胃给予生理盐水。分别于给药24 h、4 d、7 d后,随机取每组8只大鼠,处死取材。采用苏木精-伊红(HE)染色法观察各组各时期大鼠胃组织损伤情况并进行病理损伤评分,实时荧光定量聚合酶链式反应(RT-PCR)法检测各组各时期大鼠胃组织SCF、C-kitmRNA表达水平,蛋白免疫印迹(Westernblot)法检测各组各时期大鼠胃组织SCF、C-kit蛋白相对表达量。结果:正常组与同期假手术组大鼠胃黏膜病理评分、胃组织SCF、C-kitmRNA及蛋白表达比较,差异均无统计学意义(P>0.05);正常组、假手术组上述指标不同时间点组内比较,差异均无统计学意义(P>0.05)。模型组大鼠胃黏膜各观察时点病理评分均明显高于同期正常组、假手术组(P<0.01),胃组织SCF、C-kitmRNA及蛋白相对表达量均明显低于同期正常组、假手术组(P<0.01)。黄连解毒汤组、莫沙必利组大鼠各观察时点胃黏膜病理评分均明显低于同期模型组(P<0.01),给药7 d时评分均明显低于同组给药24 h、4 d时(P<0.05,P<0.01);黄连解毒汤组大鼠各观察时点胃黏膜病理评分均明显低于同期莫沙必利组(P<0.01)。黄连解毒汤组、莫沙必利组大鼠各观察时点胃组织SCF、C-kitmRNA及蛋白相对表达量均明显高于同期模型组(P<0.01),给药7 d时上述指标相对表达量均明显高于同组给药24 h、4 d时(P<0.05,P<0.01);黄连解毒汤组大鼠各观察时点上述指标相对表达量均明显高于同期莫沙必利组(P<0.01)。结论:脑出血急性期常继发急性胃黏膜损伤,黄连解毒汤对脑出血急性期胃黏膜损伤有一定的保护作用,其可能通过调控SCF/C-kit信号通路保护胃黏膜,有效减轻胃黏膜损伤。

关键词：脑出血胃损伤黄连解毒汤 SCF/C-kit信号通路胃黏膜病理评分莫沙必利

Phase-tailored assembly and encoding of dissipative soliton molecules

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Light(Science & Applications) 2023年第6期12卷 1061-1070页

作者： Yusong liu Siyun Huang Zilong Li Haoguang liu Yixiang Sun Ran Xia Lisong Yan Yiyang Luo huanhuan liu Gang Xu Qizhen Sun Xiahui Tang Perry Ping Shum School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhanChina Key Laboratory of Optoelectronic Technology and Systems(Ministry of Education) Chongqing UniversityChongqingChina School of Engineering and Materials Science Queen Mary University of LondonLondonUK Department of Electronic and Electrical Engineering Southern University of Science and TechnologyShenzhenChina

Self-assembly of particle-like dissipative solitons,in the presence of mutual interactions,emphasizes the vibrant concept of soliton molecules in varieties of laser *** manipulation of the molecular patterns,held by the degrees of freedom of internal motions,still remains challenging to explore more efficient and subtle tailoring approaches for the increasing ***,we report a new phase-tailored quaternary encoding format based on the controllable internal assembly of dissipative soliton *** manipulation of the energy exchange of soliton-molecular elements stimulates the deterministic harnessing of the assemblies of internal ***-assembled soliton molecules are tailored into four phase-defined regimes,thus constituting the phase-tailored quaternary encoding *** phase-tailored streams are endowed with great robustness and are resistant to significant timing *** these results experimentally demonstrate the programmable phase tailoring and exemplify the application of the phase-tailored quaternary encoding,prospectively promoting high-capacity all-optical storage.

关键词： soliton dissipative quaternary

高速高载下天然橡胶-反式聚异戊二烯橡胶复合材料的耐磨性

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复合材料学报 2022年第6期39卷 2607-2618页

作者：庞松刘欢欢于洋吴友平北京化工大学北京市新型高分子材料制备与加工重点实验室北京100029

飞机轮胎在高速高载下使用,其胎面橡胶复合材料耐磨性直接影响轮胎使用寿命。利用实验室自研磨耗机模拟了飞机轮胎在实际行驶过程中受到的高速(>11 Hz)高载荷(>1.8 MPa),探究了载荷、转速和炭黑(CB)用量对天然橡胶-反式聚异戊二烯橡胶... 详细信息

飞机轮胎在高速高载下使用,其胎面橡胶复合材料耐磨性直接影响轮胎使用寿命。利用实验室自研磨耗机模拟了飞机轮胎在实际行驶过程中受到的高速(>11 Hz)高载荷(>1.8 MPa),探究了载荷、转速和炭黑(CB)用量对天然橡胶-反式聚异戊二烯橡胶复合材料(NR-TPI)耐磨性的影响,并结合橡胶磨耗表面形貌和磨屑的形态特征提出了相关影响机制。结果表明,胶料的磨耗随载荷增大而增大,转速对耐磨性的影响小于载荷。当转速从600 r/min增大到800 r/min时,磨耗速率增大,再增大转速,磨耗速率无明显变化。炭黑用量为40或45份的材料磨耗速率接近,但当炭黑用量为50份时,材料的耐磨性显著提升。观察发现磨耗表面出现黏腻的降解层,且磨屑中同时包含微米级的微粒磨屑和大尺寸卷状磨屑,说明高速高载下耐磨性主要取决于表面层降解和降解层被剥离这两个过程的动态循环,前者占主导时主要发生微粒磨耗,后者占主导时起卷磨耗为主要磨耗机制。载荷和转速对耐磨性的影响主要是通过对这两个过程的影响来实现的。

关键词：天然橡胶反式聚异戊二烯橡胶高载荷高速耐磨性磨耗机制炭黑用量

Hydrothermal Synthesized Co-Ni3S2 Ultrathin Nanosheets for Efficient and Enhanced Overall Water Splitting

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Chemical Research in Chinese Universities 2019年第2期35卷 179-185页

作者： JIAN Juan YUAN Long LI He liu huanhuan ZHANG Xinghui SUN Xuejiao YUAN Hongming FENG Shouhua State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012P.R.China Key Laboratory of Functional Materials Physics and Chemistry Ministry of EducationJilin Normal UniversitySiping 136000R R. China

We used the one-step hydrothennal controlled synthesis method for Co-Ni3S2 ultrathin nanosheets grown directly on nickel foam(NF).The as-synthesized Co-Ni3S2/NF showed eiilianced activities in the hydrogen evolution reaction(HER),oxygen evolution reaction(OER)and better overall water splitting(OWS)efficiency than the iin-doped Ni3S2/*** voltage of Co-Ni3S2/NF for OWS was only 1.58 V at the current density of 10 niA/cm^2 and with long time(>30 h)current output during the current-density(i-t)*** good i-t pertonnance was also observed in both HER and OER ***,the Co-Ni3S2/NF showed a large current density(>1A/cm^2)for both HER and *** the current densities reached 100 and 1000 mA/cm^2,the required overpotentials tor Co-Ni3S2/NF were 0.35 and 0.75 V for OER and 0.30 and 0.85 V for ***,after introducing Co,the activity of Ni3S2-based material was strongly enhanced.

关键词： Co-Ni3S2/nickel tbam(NF) Ultrathin nanosheet Water splitting Hydrogen evolution reaction Oxygen evolution reaction

数字经济背景下金融科技的创新发展与监管转型——基于监管沙盒视角

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经济与管理研究 2022年第4期43卷 67-81页

作者：戚聿东刘欢欢北京师范大学经济与工商管理学院北京100875

数字经济背景下的金融科技具有创造性破坏的特征,其带来的创新收益和风险成本同时发展、相互转换,为传统金融监管带来严峻挑战,亟需通过监管转型实现激励创新和风险控制的动态平衡。在适应性监管理念逐渐受到认可的背景下,监管沙盒作为... 详细信息

数字经济背景下的金融科技具有创造性破坏的特征,其带来的创新收益和风险成本同时发展、相互转换,为传统金融监管带来严峻挑战,亟需通过监管转型实现激励创新和风险控制的动态平衡。在适应性监管理念逐渐受到认可的背景下,监管沙盒作为适应性监管的实践形式,能够为市场各类主体带来经验密集型的收益:通过真实世界的试验结果降低技术不确定性,基于有效的信息交互减少信息不对称性,有效化解监管者与被监管者、新进入者与后进入者之间的矛盾,在控制风险的基础上最大限度地推动创新。因此,监管沙盒不仅是一项创新工具,更是推动监管转型由理论走向实际的重要依托。

关键词：数字经济金融科技金融监管监管沙盒监管转型

Pentacoordinate Phosphoranes as Versatile Reagents in Fluoroalkylation Reactions

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CCS Chemistry 2024年第1期6卷 165-176页

作者： huanhuan Song Weihao Li Xiaoying Wang Kaiteng Wang Jingwen Li Shuai liu Pin Gao Xin-Hua Duan Jinbo Hu Mingyou Hu School of Chemistry Engineering Research Center of Energy Storage Materials and DevicesMinistry of EducationXi’an Key Laboratory of Sustainable Energy Material ChemistryXi’an Jiaotong UniversityXi’an 710049 Key Laboratory of Organofluorine Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032

A general method for the synthesis of bench-stable bis(difluoromethyl)pentacoordinate phosphoranes has been *** reaction is rapid,operationally simple,and easily *** pentacoordinate phosphoranes can generate both difluoromethyl radical(·CF_(2)H)and difluorocarbene(:CF_(2))***,a variety of fluoroalkylation transformations havebeen achieved by·CF_(2)H,such asoxidativedifluoromethylation of electron-deficient heterocycles,nickel/photoredox dual-catalyzed difluoromethylation of aryl bromides,and photoredox difluoromethylation of alkenes,or by:CF_(2),such as gem-difluorocyclopropanation of alkenes,base-promoted difluoromethylation of heteroatom nucleophiles,Pd-catalyzed difluoromethylation of arylboronic acids,and Cu-mediated trifluoromethylation of aryl iodides(via:CF_(2) and recombined CF_(3)-).These fluoroalkylation methods have been successfully applied to late-stage fluoroalkylation of drugs and drug-like molecules.

关键词： pentacoordinate phosphorane difluoromethyl radical difluorocarbene difluoromethylation fluoroalkylation

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牛出血性败血症的诊断和防控措施

农业技术与装备 2024年第1期 133-135页

作者：冯刚王海敏付涛刘欢欢唐山动物园河北唐山063021 天津动物园天津300381

牛出血性败血症是现代规模化养牛场常见的一类急性、传染性疾病,具有传染性强、传播速度快、致死率高等特征,对牛健康及养牛业发展影响甚大,如何有效防控牛出血性败血症成为行业工作者及广大养殖场户关注的热点问题。通过对牛出血性败... 详细信息

牛出血性败血症是现代规模化养牛场常见的一类急性、传染性疾病,具有传染性强、传播速度快、致死率高等特征,对牛健康及养牛业发展影响甚大,如何有效防控牛出血性败血症成为行业工作者及广大养殖场户关注的热点问题。通过对牛出血性败血症的流行病学、诊断要点的分析研究,提出了可行的综合防控措施。

关键词：牛出血性败血症流行病学诊断要点防控措施