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Rigidity of non-renormalizable Newton maps

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Science China Mathematics 2024年第4期67卷 855-872页

作者： Pascale Roesch yongcheng Yin Jinsong Zeng Institut de Mathématiques de Toulouse Universite Paul SabatierToulouse 31062France School of Mathematical Sciences Zhejiang UniversityHangzhou 310027China College of Mathematics and Statistics Shenzhen UniversityShenzhen 518061China

Non-renormalizable Newton maps are rigid.More precisely,we prove that their Julia sets carry no invariant line fields and that a topological conjugacy between them is equivalent to a quasiconformal conjugacy.

关键词： Newton map non-renormalizable rigidity invariant line field

Wearable ultrasensitive and rapid human physiological monitoring based on microfiber Sagnac interferometer

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Science China(Information Sciences) 2024年第3期67卷 281-290页

作者： Xin WANG Hongyou ZHOU Meihua CHEN yongcheng HE Zhishen ZHANG Jiulin GAN Zhongmin YANG State Key Laboratory Luminescent Materials and Devices Institute of Optical Communication MaterialsSpecial Glass Fiber and Device Engineering Technology Research and Development Center of Guangdong ProvinceGuangdong Provincial Key Laboratory of Fiber Laser Materials and Applied TechniquesSouth China University of Technology Guangdong-Hong Kong-Macao Joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology Foshan University

High-sensitive and fast-responding flexible strain sensors are essential for the smart wearable devices that precisely and dynamically perceive the weak deformations induced by human physiological signals. Here, a flexible strain sensor via polydimethylsiloxane(PDMS)-encapsulated microfiber Sagnac interferometer was designed and prepared for monitoring the human pulse signals and sound vibrations. The sensor achieved a record-breaking sensitivity(gauge factor, GF = 9977) and an extremely low detection limit(0.00025%) due to the strong polarization-dependent coupling effect in the microfiber coupler and the polarization-mixing effect in the Sagnac loop. The relative intensity demodulation method also enabled a fast response time of 10 μs. The wearable pulse measurements were implemented by attaching this flexible strain sensor directly to human skin at various locations and the waveform details were accurately captured. Taking advantage of the ultra-high sensitivity and fast response performance of the prepared sensor, the real-time dynamic acquisition of the underwater weak signal, such as the hydro-acoustic waves with a wide range of 20 Hz–16.86 k Hz, has been demonstrated. These initial results pave the way for a new and innovative category of underwater wearable devices with rapid detection of human physiological signals and weak environmental vibrations.

关键词： flexible strain sensor microfiber Sagnac interferometer underwater detection

All-electrical switching of a topological non-collinear antiferromagnet at room temperature

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National Science Review 2023年第2期10卷 123-130页

作者： yongcheng deng Xionghua Liu Yiyuan Chen Zongzheng Du Nai Jiang Chao Shen Enze Zhang Houzhi Zheng Hai-Zhou Lu Kaiyou Wang State Key Laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of Sciences Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences Institute for Quantum Science and Engineering and Department of Physics Southern University of Science and Technology (SUSTech) International Quantum Academy Beijing Academy of Quantum Information Sciences Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences

Non-collinear antiferromagnetic Weyl semimetals,combining the advantages of a zero stray field and ultrafast spin dynamics,as well as a large anomalous Hall effect and the chiral anomaly of Weyl fermions,have attracted extensive interest.However,the all-electrical control of such systems at room temperature,a crucial step toward practical application,has not been reported.Here,using a small writing current density of around 5 × 106A·cm-2,we realize the all-electrical current-induced deterministic switching of the non-collinear antiferromagnet Mn3Sn,with a strong readout signal at room temperature in the Si/SiO2/Mn3Sn/AlOxstructure,and without external magnetic field or injected spin current.Our simulations reveal that the switching originates from the current-induced intrinsic non-collinear spin-orbit torques in Mn3Sn itself.Our findings pave the way for the development of topological antiferromagnetic spintronics.

关键词： spintronics non-collinear antiferromagnetic Weyl semimetals all-electrical switching spin-orbit torques

A strategy based on water soluble coal tar pitches to construct MnO_(2)@C composite materials with high electrochemical performance

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Science China(Technological Sciences) 2024年第1期67卷 311-320页

作者： LIU Bo WANG Kun GUO ZhaoQi HAN BeiBei XU GuiYing JU DongYing AN BaiGang LI yongcheng NI ZhenYong ZHOU WeiMin Key Laboratory of Energy Materials and Electrochemistry Research Liaoning Province University of Science and Technology LiaoningAnshan 114051China Advanced Science Research Laboratory Saitama Institute of TechnologyFusaiji 1690Japan Liaoning Starry Sky Sodium Battery Co. Ltd.Anshan 114051China Sinosteel Anshan Research Institute of Thermo-Energy Co. Ltd.Anshan 114051China State Key Laboratory of Marine Resource Utilization in South China Sea Hainan Provincial Key Lab of Fine ChemistrySchool of Chemical Engineering and TechnologyHainan UniversityHaikou 570228China Key Laboratory of Advanced Fuel Cells and Electrolyzers Technology of Zhejiang Province Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China

The water soluble coal tar pitches(WS-CTPs)were successfully prepared and used to construct the MnO_(2)@C composite materials by a hydrothermal method.It is interestingly observed that the structures and morphologies of MnO_(2)@C materials can be controlled by controlling the dosages of WS-CTPs and KMnO4.Meanwhile,it is aware that MnO_(2)exists in the MnO_(2)@C materials in an amorphous state.Compared with MnO_(2),MnO_(2)@C materials output a remarkable improvement in electrochemical performance.For instance,MnO_(2)@C-0.3 shows the storage capacity at 965.7 mA h g^(−1)after 300 cycles at a current density of 0.1 A g^(−1).In addition,after 600 cycles at a current density of 1.0 A g^(−1),the storage capacity of MnO_(2)@C-0.3 still keeps 450.3 mA h g^(−1),indicating that MnO_(2)@C-0.3 owns tremendous cycle stability at a high current density.In view of the fact that the coal tar pitches possess great cost advantages,the strategy of using WS-CTPs as a carbon source to cover the metal oxides is a competitive way to expand the application of metal oxides in the fabrication of electrodes of LIBs.

关键词： water soluble coal tar pitches MnO_(2) composite materials lithium ion batteries(LIBs) energy storage systems(ESSs) coal tar pitches

Oscillation of current-induced interfacial spins reorientation in a like-synthetic antiferromagnet/antiferromagnet system

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Science China(Physics,Mechanics & Astronomy) 2021年第6期64卷 106-113页

作者： XiongHua Liu yongcheng deng XiuKai Lan RunZe Li KaiYou Wang State Key Laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Beijing Academy of Quantum Information Sciences Beijing 100193China Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100049China

Antiferromagnets have been attracting tremendous interest in the spintronics community due to their intrinsic appealing properties,such as zero stray field and ultrafast spin dynamics.Recently,the electrical manipulation of bulk properties of antiferromagnets has been widely studied,but exploring the use of antiferromagnetic(AFM)interfacial properties to investigate some key issues in spintronic devices is urgently desired.In this study,the magnetic and spin transport properties mediated by interlayer exchange coupling(IEC)are examined through spin-orbit torque(SOT)-induced tunability of interfacial spins in heavy-metal/like-synthetic antiferromagnet/antiferromagnet heterostructure devices.We found that the exchange bias and coercivity and the critical current density for SOT switching can be modulated by IEC,associating with the oscillation of SOTinduced interfacial spins reorientation at zero field,which can be well understood with the modified Ruderman-Kittel-KasuyaYosida model.Our finding opens a new route for understanding and using the AFM interfacial spins in spintronics.

关键词： spintronics antiferromagnetic interfacial spins spin-orbit torque oscillation

Elevated Kallistatin promotes the occurrence and progression of non-alcoholic fatty liver disease

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1730-1744页

作者： Zhenzhen Fang Gang Shen Yina Wang Fuyan Hong Xiumei Tang yongcheng Zeng Ting Zhang Huanyi Liu Yanmei Li Jinhong Wang Jing Zhang Anton Gao Weiwei Qi Xia Yang Ti Zhou Guoquan Gao Department of Biochemistry Zhongshan School of MedicineSun Yat-Sen UniversityGuangzhou 510080China Department of VIP Medical Center the Third Affiliated Hospital of Sun Yat-Sen UniversityGuangzhou 510080China Physical Examination Center the Third Affiliated Hospital of Sun Yat-Sen UniversityGuangzhou 510080China Department of Clinical Laboratory Guangzhou First People's HospitalGuangzhou 510080China Guangdong Key Laboratory of Liver Disease Research the Third Affiliated Hospital of Sun Yat-Sen UniversityGuangzhou 51008China Department of Health Sciences College of Health SolutionsArizona State UniversityTempeUSA Guangdong Engineering&Technology Research Center for Gene Manipulation and Biomacromolecular Products Sun Yat-Sen UniversityGuangzhou 510080China Guangdong Province Key Laboratory of Diabetology Guangzhou 510o80China Guangdong Province Key Laboratory of Brain Function and Disease Zhongshan School of MedicineSun Yat-Sen UniversityGuangzhou 510080China

Non-alcoholic fatty liver disease(NAFLD)is the most common chronic liver disease worldwide,and the development of nonalcoholic steatohepatitis(NASH)might cause irreversible hepatic damage.Hyperlipidemia(HLP)is the leading risk factor for NAFLD.This study aims to illuminate the causative contributor and potential mechanism of Kallistatin(KAL)mediating HLP to NAFLD.221 healthy control and 253 HLP subjects,62 healthy control and 44 NAFLD subjects were enrolled.The plasma KAL was significantly elevated in HLP subjects,especially in hypertriglyceridemia(HTG)subjects,and positively correlated with liver injury.Further,KAL levels of NAFLD patients were significantly up-regulated.KAL transgenic mice induced hepatic steatosis,inflammation,and fibrosis with time and accelerated inflammation development in high-fat diet(HFD)mice.In contrast,KAL knockout ameliorated steatosis and inflammation in high-fructose diet(HFruD)and methionine and choline-deficient(MCD)diet-induced NAFLD rats.Mechanistically,KAL induced hepatic steatosis and NASH by down-regulating adipose triglyceride lipase(ATGL)and comparative gene identification 58(CGl-58)by LRP6/Gas/PKA/GSK3βpathway through down-regulating peroxisome proliferator-activated receptor(PPARy)and up-regulating kruppel-like factor four(KLF4),respectively.CGl-58 is bound to NF-kB p65 in the cytoplasm,and diminishing CGl-58 facilitated p65 nuclear translocation and TNFa induction.Meanwhile,hepatic CGl-58-overexpress reverses NASH in KAL transgenic mice.Further,free fatty acids up-regulated KAL against thyroid hormone in hepatocytes.Moreover,Fenofibrate,one triglyceride-lowering drug,could reverse hepatic steatosis by down-regulating KAL.These results demonstrate that elevated KAL plays a crucial role in the development of HLP to NAFLD and may be served as a potential preventive and therapeutic target.

关键词： GSK3β inflammation elevated

Rhizopus stolonifer几丁质脱乙酰酶的异源表达及其与几丁质酶的协同作用研究

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食品与发酵工业 2024年第2期50卷 177-183页

作者：张巧李永成食品科学与工程学院(海南大学) 海南海口570228 食品科学与工程技术研究院(贺州学院) 广西贺州542899

几丁质脱乙酰酶(chitin deacetylase,CDA)是几丁质生物转化为壳聚糖的关键酶。然而,目前报道的高活性CDAs非常少。为了获得高效的CDA,并提高其对几丁质的生物转化效率,该研究对来源于Rhizopus stolonifer中的CDA进行基因克隆、表达及纯... 详细信息

几丁质脱乙酰酶(chitin deacetylase,CDA)是几丁质生物转化为壳聚糖的关键酶。然而,目前报道的高活性CDAs非常少。为了获得高效的CDA,并提高其对几丁质的生物转化效率,该研究对来源于Rhizopus stolonifer中的CDA进行基因克隆、表达及纯化,获得几丁质脱乙酰酶Rs CDA1,研究其酶学性质并探究其与来源于Vibrio harveyi的几丁质酶Vh Chit2对几丁质的协同水解作用。结果表明,Rs CDA1的比酶活力为5.2 U/mg,在45℃、pH 6.5条件下活性最高,在温度低于40℃、pH 6.5~8.0保持较好的稳定性。1 mmol/L的Ca^(2+)、Mn^(2+)、Mg^(2+)、Zn^(2+)、Ba^(2+)和Co^(2+)对Rs CDA1的活力有促进作用;1 mmol/L的Ni^(2+)和Cu^(2+)对该酶有抑制作用。此外,Rs CDA1与Vh Chit2在几丁质水解中表现出良好的协同降解和脱乙酰作用。Rs CDA1与Vh Chit2(摩尔浓度比为10∶1)在50℃、pH 6.5条件下水解20 mg/mL几丁质2 h时,对几丁质酶和CDA的协同度分别达到120.3%和175.6%。与单独使用Rs CDA1相比(27.5%),两者协同水解时几丁质的脱乙酰度增加到35.3%。因此,Rs CDA1在几丁质的生物转化中具有潜在的应用前景。

关键词：几丁质脱乙酰酶几丁质壳聚糖协同作用脱乙酰度

12Cr5Mo压力容器制造监督检验及工艺优化

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化工设备与管道 2024年第3期61卷 16-21页

作者：戴永成江苏省特种设备安全监督检验研究院泰州分院江苏泰州225400

以某单位首次试制造12Cr5Mo耐热钢制压力容器为例,介绍了耐热钢制压力容器制造监督检验过程中的质量控制,重点描述了12Cr5Mo的材料入库检验控制、焊接相关过程的控制、热处理的工艺控制过程。通过分析压力容器本体上不同受压元件之间的... 详细信息

以某单位首次试制造12Cr5Mo耐热钢制压力容器为例,介绍了耐热钢制压力容器制造监督检验过程中的质量控制,重点描述了12Cr5Mo的材料入库检验控制、焊接相关过程的控制、热处理的工艺控制过程。通过分析压力容器本体上不同受压元件之间的焊接结构形式以及12Cr5Mo的材料性能,根据提供的焊接工艺评定、焊工资格项目、热处理工艺,发现相关部分焊评焊工资质不覆盖问题。通过优化热处理工艺和选择合适焊评焊工,最终顺利通过了无损检测及耐压试验。

关键词： 12Cr5Mo 耐热钢压力容器监督检验

温度分层环境中水下航行器机动下潜热尾流特征

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哈尔滨工程大学学报 2024年第6期45卷 1111-1118页

作者：李戈洋杜永成杨立海军工程大学动力工程学院湖北武汉430033 海军工程大学振动与噪声研究所湖北武汉430033

为研究水下航行器热尾流引起的水面温度异常,本文采用有限体积法建立三维SUBOFF数学模型。使用Fluent UDF、Patch分别控制水下航行器机动下潜方式和水域温度分层。数值模拟结果表明:水下航行器在机动下潜时,热尾流在水面会形成由2条不... 详细信息

为研究水下航行器热尾流引起的水面温度异常,本文采用有限体积法建立三维SUBOFF数学模型。使用Fluent UDF、Patch分别控制水下航行器机动下潜方式和水域温度分层。数值模拟结果表明:水下航行器在机动下潜时,热尾流在水面会形成由2条不连续高温热斑组成的椭圆形温度异常区,且正温度梯度分层水域会增强热尾流引起的水面温度异常。在无热排放条件下,水下航行器机动下潜会对水域温度分层发生较大扰动,从而出现冷尾迹。相反,受热排放影响,热尾流以肾形涡的形式向上浮升,涡结构尺度随着航行距离的增大而增大,核心温度随着航行距离的增大而减小。正温度梯度分层海水会增强冷却水引起的海面温度异常特征,且温度梯度越大,热斑越连续,热斑核心最高温度为292.24 K,与周围海水温度差值为0.12 K。

关键词：水下航行器热尾流有限体积法机动下潜温度分层高温热斑椭圆形温度异常区正温度梯度

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