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Zeeman effects on d-wave superconductor and tunneling spectrum in normal-metal/d-wave superconductor tunnel junction

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science China(Physics,Mechanics & Astronomy) 2006年第5期49卷 597-605页

作者： DONG Zhengchao Department of Physics Huaiyin Teachers CollegeJiangsu Province Key Laboratory for Chemistry of Low-Dimensional MateeialsHuai'an 223001China

We study the Zeeman effect on the d-wave superconductor and tunneling spectrum in normal-metal(N)/d-wave superconductor(S) junction by applying a Zeeman magnetic field to the S. It is shown that: (1) the Zeeman magnetic field can lead to the S gap decreasing, and with the increase in Zeeman energy, the superconducting state is changed to the normal state, exhibiting a first-order phase transition; (2) the Zeeman magnetic field may make the zero-bias conductance peak split into two peaks, and the energy difference between the two splitting peaks in the conductance spectrum is equal to 2h0 (h0 is the Zeeman energy); (3) both the barrier strength of interface scattering and the temperature can lower the magnitudes of splitting peaks, of which the barrier strength can lead to the splitting peaks becoming sharp and the temperature can smear out the peaks, however, neither of them can influence the Zeeman effect.

关键词： Zeeman effects d-wave superconductor tunneling spectrum

Structural design for electrocatalytic water splitting to realize industrial-scale deployment: Strategies, advances, and perspectives

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Journal of Energy Chemistry 2022年第7期31卷 129-153,I0004页

作者： Xianwei Fu Ruijuan Shi Shilong Jiao Mengmeng Li Qiuye Li Engineering research Center for Nanomaterials National&Local Joint Engineering Research Center for Applied Technology of Hybrid NanomaterialsHenan UniversityKaifeng 475004HenanChina Key Lab for Special Functional Materials of Ministry of Education Collaborative Innovation Center of Nano Functional Materials and ApplicationsHenan UniversityHenan UniversityKaifeng 475004HenanChina

The green hydrogen generation powered by renewable electricity promises the potential decarbonization of the hard-to-abate sector and is essential for the fulfillment of the Paris Agreement that attempts to limit the global average temperature rise in the range of 1.5–2.0 ℃ above the pre-industrial level by the end of this century. Tremendous efforts have been devoted to the optimization of the electrocatalytic performance of the catalysts under industrial-relevant current densities via rational structure design,which induces a preferential electron distribution that favors the adsorption/desorption behavior of the key intermediates, thus accelerating the reaction kinetics. In this review, a brief introduction of the current energy status will be first presented to necessitate the importance of green *** by the basic concepts and fundamental understanding of the reaction mechanisms, we present efficient strategies for the enhancement of the electrocatalytic performance of the catalysts to meet the rigorous requirement under industrial conditions and the in-depth understanding behind the reinforcement will be briefly discussed next. Then the recent advances regarding the rational design of electrocatalysts operating at an industrial scale will be summarized. Finally, the challenges and perspectives in this thriving field will be proposed from our point of view.

关键词： Overall water splitting Industrial-scale current density Structural design Hydrogen evolution reaction Oxygen evolution reaction

New freshwater plesiosaurian materials from the Middle Jurassic Xintiangou Formation of the Sichuan Basin, southwestern China

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Journal of Palaeogeography 2020年第4期9卷 469-479页

作者： Feng Zhang Hai-Dong Yu Can Xiong Zhao-Ying Wei Guang-Zhao Peng Xue-Fang Wei Chongqing Laboratory of Geoheritage Protection and research No.208 Hydrogeological and Engineering Geological TeamChongqing Bureau of Geological and Mineral Resource Exploration and DevelopmentChongqing 400700China Zigong Dinosaur Museum Zigong 643000Sichuan ProvinceChina Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China China University of Geosciences(Beijing) Beijing 100083China Cores and Samples Centre of Natural Resources Chinese Geological SurveyBeijing 100192China

Sichuan Basin is very famous for the Mesozoic reptiles, especially the Jurassic dinosaurs. Here, we report some isolated plesiosaurian teeth and vertebrae newly excavated from the Middle Jurassic Xintiangou Formation in Yunyang county, Chongqing City, the northeastern region of the Sichuan Basin, southwestern China. The specimens are referred to Pliosauroidea based on the combination of the following features: the circular cross-section of the tooth crown, apicobasal ridges fully covering the enamel surface and reaching to the apex, the short and amphicoelous centrum, the centrum shorter than wide or tall, and the absence of a keel on the lateral surface of the cervical centrum. With the fragmentary nature, it is undetermined whether the Yunyang specimens belong to a known taxon or represent a new species of Plesiosauria. These plesiosaurian specimens further demonstrate that the freshwater plesiosaurians are common in the Jurassic deposits of the Sichuan Basin. For a comprehensive knowledge of the plesiosaurians of the basin in origin, distribution and diversity, to discover new and more complete specimens is necessarily the first priority.

关键词： Plesiosauria Pliosauroidea Middle Jurassic Xintiangou Formation Sichuan Basin

Asymptotic expansions of finite element solutions to Robin problems in H^3 and their application in extrapolation cascadic multigrid method

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science China Mathematics 2014年第4期57卷 687-698页

作者： HU HongLing CHEN ChuanMiao PAN KeJia College of Mathematics and Computer science Key Laboratory of High Performance Computing and Stochastic Information Processing (Ministry of Education of China)Hunan Normal University School of Mathematics and Statistics Central South University Key Laboratory of Metallogenic Prediction of Nonferrous Metals Ministry of EducationSchool of Geosciences and Info-PhysicsCentral South University

For the Poisson equation with Robin boundary conditions,by using a few techniques such as orthogonal expansion(M-type),separation of the main part and the finite element projection,we prove for the first time that the asymptotic error expansions of bilinear finite element have the accuracy of O(h3)for u∈*** on the obtained asymptotic error expansions for linear finite elements,extrapolation cascadic multigrid method(EXCMG)can be used to solve Robin problems ***,by virtue of Richardson not only the accuracy of the approximation is improved,but also a posteriori error estimation is ***,some numerical experiments that confirm the theoretical analysis are presented.

关键词： finite element Richardson extrapolation Robin problem asymptotic expansion cascadic multi-grid method

Aza-BODIPY based probe for photoacoustic imaging of ONOO;in vivo

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Chinese Chemical Letters 2021年第12期32卷 3886-3889页

作者： Danghui Ma Shumin Hou Chaeeon Bae Thanh Chung Pham Songyi Lee Xin Zhou Department of Chemistry College of Chemistry and Chemical EngineeringQingdao 266071China Qingdao Cancer Institute Qingdao UniversityQingdao 266071China Department of Chemistry Pukyong National UniversityBusan 48513Korea Industry 4.0 Convergence Bionics Engineering Pukyong National UniversityBusan 48513Korea

The effective detecting ONOO^(-)variations in vivo is of great importance to well understand the complex pathophysiological processes. We reported here a photoacoustic(PA) probe AZB-1 for imaging ONOO;in vivo. AZB-1 showed an originally strong photoacoustic signal at 660 nm. And its PA signal can be turned off by shutting the ICT effect caused by the conjugated electron withdrawing group at 2-position of the aza-BODIPY core. Moreover, the probe was successfully employed to imaging ONOO^(-)variations in inflammatory mice models. Wisely utilized this strategy may serve as powerful platforms for the preparation of novel PA chemosensors.

关键词： Photoacoustic ONOO^(-) Imaging Aza-BODIPY In vivo

Mechanical behaviour of medium-grained sandstones exposed to differential cyclic loading with distinct loading and unloading rates

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第6期14卷 1849-1871页

作者： Zhengyang Song Heinz Konietzky Yunfeng Wu Kun Du Xin Cai Department of Civil Engineering School of Civil and Resource Engineering University of Science and Technology Beijing Geotechnical Institute TU Bergakademie Freiberg School of Resources and Safety Engineering Central South University

This work aims to investigate the mechanical behaviour of medium-grained sandstones under cyclic loading with different loading/unloading rates. This type of cyclic loading is called differential cyclic loading(DCL) and is considered for testing rock behaviour. In the experiments, constant amplitude and multi-level cyclic loadings were performed. Three loading modes were designed to consider different relationships between loading and unloading rates. Axial strain evolution and energy dissipation were analysed for different loading/unloading rates and maximum cyclic load level. The correlations between P-wave velocities and strengths of rocks deduced from this research are compared with existing published data. The relationships between final strength and axial strain at failure under different loading patterns were also discussed and a rough assessment of the remaining fatigue life is introduced using the predicted value by fitting the axial peak strain.

关键词： Differential cyclic loading (DCL) Rock fatigue Loading/unloading rate Energy dissipation Damage accumulation

A 1.8-V 240-MHz 2.19-mW Four-Stage CMOS OTA with a Segmenting Frequency Compensation Technique

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Chinese Journal of Electronics 2021年第5期30卷 853-860页

作者： LIANG Yuhua ZHENG Zirui LIU Shubin LI Dengquan DING Ruixue ZHU Zhangming School of Microelectronics Xidian University

A four-stage Operational transconductance amplifier(OTA) used in an infrared temperature sensor adopting the proposed Feed-forward Gm-stage and segmenting nested Miller compensation technique is presented. The purpose of the proposed segment compensation is primarily to make more amplifier stages concatenated. The circuit linked several transconductance stages to form a segment, and linked several segments to form a large multistage amplifier. For example, a twostage amplifier linked with a three-stage amplifier can realize a five-stage amplifier, two three-stage amplifiers linked can realize a six-stage amplifier. A four-stage amplifier in the form of 2+2(two stages and two stages)was used as an example to verify this compensation method. The proposed OTA is designed in the 180 nm complementary metal oxide semiconductor process. It consists of two parts which ensure the stability and improve the bandwidth performance. The first part is a feedforward transconductance stage, and the second part is the two-segment transconductance stages with the Miller compensation techniques employed within and between the two segments. Based on the small-signal model,stability analysis and theoretical derivation are performed in theory. On condition of a 2-pF load capacitance, a direct current gain of 109 dB and a gain-bandwidth of 240 MHz with a phase margin of 50° can be achieved. The proposed design consumes 2.19 mW in a 1.8-V supply voltage. The transient simulation indicates that the settling time of the output is 19 ns with the settling error being 1%, and the slew rate is 114 V/μs.

关键词： six-stage amplifier power 2.19 mW time 19.0 ns transient simulation four-stage Operational transconductance amplifier theoretical derivation compensation large multistage amplifier four-stage amplifier operational amplifiers five-stage amplifier small-signal model three-stage amplifier segmenting frequency compensation technique phase margin bandwidth performance complementary metal oxide semiconductor process CMOS analogue integrated circuits gain 109.0 dB feedforward amplifiers stability analysis two-stage amplifier capacitance 2 pF multistage amplifier two-segment transconductance stages integrated circuit design voltage 1.8 V four-stage CMOS OTA segmenting nested Miller compensation technique circuit stability bandwidth 240.0 MHz size 180.0 nm feedforward transconductance stage

Room-temperature terahertz detection based on CVD graphene transistor

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Chinese Physics B 2015年第4期24卷 378-382页

作者：杨昕昕孙建东秦华吕利苏丽娜闫博李欣幸张志鹏方靖岳 Key Laboratory of Nanodevices and Applications Suzhou Institute of Nano-tech and Nano-bionicsChinese Academy of Sciences University of Chinese Academy of sciences Key Laboratory of Advanced Process Control for Light Industry Department of Electronic Engineering Jiangnan University College of science National University of Defense Technology

We report the fabrication and characterization of a single-layer graphene field-effect terahertz detector, which is cou- pled with dipole-like antennas based on the self-mixing detector model. The graphene is grown by chemical vapor deposi- tion and then transferred onto an SiO2/Si substrate. We demonstrate room-temperature detection at 237 GHz. The detector could offer a voltage responsivity of 0.1 V/W and a noise equivalent power of 207 nW/Hz 1/2. Our modeling indicates that the observed photovoltage in the p-type gated channel can be well fit by the self-mixing theory. A different photoresponse other than self-mixing may apply for the n-type gated channel.

关键词： graphene field effect transistor self-mixing terahertz detection

Epidermal self-powered sweat sensors for glucose and lactate monitoring

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Bio-Design and Manufacturing 2022年第1期5卷 201-209页

作者： Xingcan Huang Jiyu Li Yiming Liu Tszhung Wong Jingyou Su Kuanming Yao Jingkun Zhou Ya Huang Hu Li Dengfeng Li Mengge Wu Enming Song Shijiao Han Xinge Yu Department of Biomedical Engineering City University of Hong KongHong Kong 999077China School of Computer science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054China

Sweat could be a carrier of informative biomarkers for health status identification;therefore,wearable sweat sensors have attracted significant attention for *** external power source is an important component of wearable sensors,however,the current power supplies,i.e.,batteries,limit further shrinking down the size of these devices and thus limit their application areas and ***,we report a stretchable self-powered biosensor with epidermal electronic format that enables the in situ detec-tion of lactate and glucose concentration in *** biofuel cells serve as self-powered sensing modules allowing the sweat sensor to exhibit a determination coefficient(R2)of 0.98 with a sensitivity of 2.48 mV/mM for lactate detection,and R2 of 0.96 with a sensitivity of 0.11 mV/μM for glucose *** microfluidic channels developed in an ultra-thin soft flexible polydimethylsiloxane layer not only enable the effective collection of sweat,but also provide excellent mechanical properties with stable performance output even under 30%*** presented soft sweat sensors can be integrated at nearly any location of the body for the continuous monitoring of lactate and glucose changes during normal daily activities such as *** results provide a promising approach to develop next-generation sweat sensors for real-time and in situ sweat analysis.

关键词： Sweat sensor Self-powered Epidermal electronics Enzymatic biofuel cells Microfluidics