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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 106-111页

作者： yuhang Zhang Cong Liu Xiyu Zhu Hai-hu Wen Center for Superconducting Physics and Materials National Laboratory of Solid State Microstructures and Department of PhysicsNational Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China

Recent claim of discovering above-room-temperature superconductivity(Tc≈400 K)at ambient pressure in copper doped apatite Pb10(PO_(4))_(6)O has stimulated world-wide enthusiasm and impulse of motion.A lot of follow-up works have been carried out with controversial *** check whether superconductivity is really present or absent in the material,we need samples which should have a rather pure phase of Pb_(10-x)Cux(PO_(4))_(6)*** we report the characterization results from the Pb_(10-x)Cux(PO_(4))_(6)O with a fraction of about 97 wt.%inferred from the fitting to the X-ray diffraction pattern,if assuming Cu2S as the only *** resistivity measurements show that it is a semiconductor characterized roughly by a ln(1/T)temperature dependence in wide temperature region without trace of *** measurements show that it has a general ferromagnetic signal with a weak superparamagnetic *** grains of the sample show clear interactions with a Nb Fe B *** detected Cu concentration is much lower than the expected nominal *** results show the absence of metallicity and superconductivity in Pb_(10-x)Cux(PO_(4))_(6)O at ambient pressure,and suggest the presence of strong correlation effect.

关键词： superconductivity Pb10(PO4)6O ferromagnetic correlation effect

基于EBS-YOLOv5的钢铁表面缺陷检测

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传感器世界 2024年第4期30卷 14-19页

作者：耿冰廖宇冯旭崔琨胡钰航崔益博湖北民族大学智能科学与工程学院湖北恩施445000

随着人工智能在工业检测领域的应用日益增加,如何快速准确地检测缺陷成为了一个热点问题。钢铁是一种重要的工业原材料,针对钢铁表面缺陷的检测问题,提出了一种基于YOLOv5的改进模型。该模型主要有2点改进:一是在头部加入SENet(压缩和... 详细信息

随着人工智能在工业检测领域的应用日益增加,如何快速准确地检测缺陷成为了一个热点问题。钢铁是一种重要的工业原材料,针对钢铁表面缺陷的检测问题,提出了一种基于YOLOv5的改进模型。该模型主要有2点改进:一是在头部加入SENet(压缩和激励网络)注意力机制,增强全局检测能力,使模型能够学习不同通道的权重信息;二是加入EVC(显性视觉中心)模块,使得模型在关注全局信息的同时,也不忽略层内局部特征和角部信息。使用了公开的数据集NEU-DET(东北大学缺陷检测任务)验证了其可行性,试验结果表明,EBS-YOLOv5模型比起YOLOv5s的准确率有了较明显的提升,mAP50(平均精度指标)提高了6.2%,仍然保持了154的检测帧率,满足工业场景下对钢铁表面的检测需求。

关键词：钢铁表面缺陷检测 EBS-YOLO SENet

Enhanced Fenton-like process over Cu/L(+)-ascorbic acid co-doping mesoporous silica for toxicity reduction of emerging contaminants

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Frontiers of Environmental Science & Engineering 2024年第4期18卷 49-60页

作者： yuhang Liu Wenxuan Deng Xiaojun Wu Chun hu Lai Lyu Key Laboratory for Water Quality and Conservation of the Pearl River Delta(Ministry of Education) Institute of Environmental Research at Greater BayGuangzhou UniversityGuangzhou 510006China

Effective removal of emerging contaminants(ECs)to minimize their impacts on human health and the natural environment is a global *** the removal of ECs in water,we fabricated a seaweed spherical microsphere catalyst with Cu cation-πstructures by in situ doping of Cu species and ascorbic acid in mesoporous silica(Cu-C-MSNs)via a hydrothermal *** results indicate that bisphenol A(BPA)is substantially degraded within 5 min under natural conditions,with its biological toxicity considerably ***,industrial wastewater could also be effectively purified by Cu-C-MSNs/H_(2)O_(2) *** presence of metal sites and the complexation of ECs via cation-πinteraction andπ-πstacking on the catalyst surface were directly responsible for the polarization distribution of electrons,thus activating H_(2)O_(2) and dissolved oxygen(DO).The removal of contaminants could be attributed primarily to 1)the activation of H_(2)O_(2) into ^(·)OH to attack the contaminants and 2)self-cleavage because of the transfer of electrons from the contaminants to the *** study provides an innovative solution for the effective treatment of ECs and has positive implications for easing global environmental crises.

关键词： Cation-πstructures Polarization electric field Fenton-like process Contaminants cleavage

Design of Low-Power Turbo Encoder and Decoder for NB-IoT

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Chinese Journal of Electronics 2024年第2期33卷 403-414页

作者： Chong ZHANG yuhang LIN Deming WANG Jianguo hu School of Microelectronics Science and Technology Sun Yat-sen University School of Physics and Telecommunication Engineering South China Normal University School of Electronics and Information Engineering South China Normal University Development Research Institute of Guangzhou Smart City Shenzhen Research Institute of Sun Yat-sen University

Turbo code is an error correction coding scheme close to the Shannon limit, usually used in wireless data transmission. Based on the parallel Turbo code algorithm, a parallel Turbo code circuit design scheme is *** the encoder, the recursive systematic convolutional encoder is multiplexed. The decoder is divided into branch metric, recursive, maximum likelihood ratio, and external information calculation modules. The decoding algorithm is based on Max-Log-MAP, controlling the component decoder in parallel. And the state metric calculation in the decoding circuit is combined to reduce the overall power consumption effectively, enabling the encoder and decoder to be used in narrowband Internet of things(NB-IoT). Finally, the hardware scheme of the main functional modules of Turbo code encoding and decoding is designed and implemented. The results show that the dynamic power consumption is less than 50 m W. The overall on-chip power consumption is reduced by 40% at the frequency of 125 MHz compared with previous jobs.

关键词： Measurement Wireless communication Power demand Systematics Turbo codes System-on-chip Power dissipation

VISCOELASTICITY AND POROELASTICITY IN ELASTOMERIC GELS

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Acta Mechanica Solida Sinica 2012年第5期25卷 441-458页

作者： yuhang hu Zhigang Suo (School of Engineering and Applied Sciences Kavli Institute for Nanobio Science and Technology Harvard University Cambridge MA 02138 USA)

An elastomeric gel is a mixture of a polymer network and a solvent. In response to changes in mechanical forces and in the chemical potential of the solvent in the environment, the gel evolves by two concurrent molecular processes： the conformational change of the network, and the migration of the solvent. The two processes result in viscoelasticity and poroelasticity, and are characterized by two material-specific properties： the time of viscoelastic relaxation and the effective diffusivity of the solvent through the network. The two properties define a material- specific length. The material-specific time and length enable us to discuss macroscopic observations made over different lengths and times, and identify limiting conditions in which viscoelastic and poroelastic relaxations have either completed or yet started. We formulate a model of homogeneous deformation, and use several examples to illustrate viscoelasticity-limited solvent migration, where the migration of the solvent is pronounced, but the size of the gel is so small that the rate of change is limited by viscoelasticity. We further describe a theory that evolves a gel through inhomogeneous states. Both infinitesimal and finite deformation are considered.

关键词： elastomer gel viscoelasticity poroelasticity creep stress relaxation

Hyperelastic model for polyacrylamide‑gelatin double network shape‑memory hydrogels

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Acta Mechanica Sinica 2021年第5期37卷 748-756,I0001页

作者： Yifu Chen Haohui Zhang Jiehao Chen Guozheng Kang yuhang hu George W Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGA 30332USA Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and EngineeringSouthwest Jiaotong UniversityChengdu 610031China School of Chemical and Biomolecular Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

A shape-memory double network hydrogel consists of two polymer networks:a chemically crosslinked primary network that is responsible for the permanent shape and a physically crosslinked secondary network that is used to fix the temporary *** formation/melting transition of the secondary network serves as an effective mechanism for the double network hydrogel’s shape-memory *** the crosslinks in the secondary network are dissociated by applying an external stimulus,only the primary network is left to support the *** the secondary network is re-formed by removing the stimulus,both the primary and secondary networks support the *** the past,models have been developed for the constitutive behaviors of double network hydrogels,but the model of shape-memory double network hydrogels is still *** work aims to build a constitutive model for the polyacrylamide-gelatin double network shape-memory hydrogel developed in our previous *** model is first calibrated by experimental data of the double network shape-memory hydrogel under uniaxial loading and then employed to predict the shape-fixing performance of the *** model is also implemented into a three-dimension finite element code and utilized to simulate the shape-memory behavior of the double network hydrogel with inhomogeneous deformations related to applications.

关键词： Shape-memory hydrogel Double network Constitutive model Finite element simulation

Sulfate-assisted Ni/Fe-based electrodes for anion exchange membrane saline splitting

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Nano Research 2024年第7期17卷 5985-5995页

作者： Yujun Han Li Shao yuhang Liu Guodong Li Tongzhou Wang Xuerong Zheng Jihong Li Xiaopeng Han Wenbin hu Yida Deng School of Materials Science and Engineering Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of EducationTianjin UniversityTianjin 300072China State Key Laboratory of Marine Resource Utilization in South China Sea School of Materials Science and EngineeringHainan UniversityHaikou 570228China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China

Saline water electrolysis is an appealing strategy for hydrogen production,attracting more attention in recent ***-based electrodes exhibit promise as catalysts for saline water ***,they suffer from the inferior service life of the oxygen evolution reaction(OER).Herein,we report an oxygen-evolution electrode consisting of a sulfate-modulated nickel-iron hydroxide(NiFeOOH)affording as the catalytic active layer and Fe-Ni3S2 as the corrosion-proof *** developed electrode only requires overpotentials of 220 and 292 mV to deliver the current density of 10 and 500 mA·cm^(−2),*** importantly,it presents long-term stability exceeding 140 and 100 h in 1 M KOH at high current densities of 500 and 1000 mA·cm^(−2),respectively,as well as 120 h for saline water electrolysis at 100 mA·cm^(−2).Experimental results reveal that the generated sulfate plays an indispensable role in improving stability and corrosion *** assembled and tested an anion exchange membrane electrolyzer with Pt/C and NiFeS/NIF as the cathode and anode,respectively,under industrial *** overall water-splitting electrolyzer achieves an impressive energy conversion efficiency of 75%±0.5%.This report offers fresh insights into the design of stable NiFe-based electrodes,which may further promote its practical applications for saline water electrolysis.

关键词： saline water electrolysis oxygen evolution reaction anode material water splitting

Combination therapy with saxagliptin and vitamin D for the preservation ofβ-cell function in adult-onset type 1 diabetes:a multi-center,randomized,controlled trial

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Signal Transduction and Targeted Therapy 2023年第5期8卷 2354-2362页

作者： Xiang Yan Xia Li Bingwen Liu Jiaqi huang Yufei Xiang yuhang hu Xiaohan Tang Ziwei Zhang Gan huang Zhiguo Xie Houde Zhou Zhenqi Liu Xiangbing Wang Richard David Leslie Zhiguang Zhou National Clinical Research Center for Metabolic Diseases Key Laboratory of Diabetes Immunology(Central South University)Ministry of Educationand Department of Metabolism and EndocrinologyThe Second Xiangya Hospital of Central South UniversityChangshaHunanChina Division of Endocrinology and Metabolism Department of MedicineUniversity of Virginia Health SystemCharlottesvilleVAUSA Division of Endocrinology Metabolism and NutritionRutgers University-Robert Wood Johnson Medical SchoolNew BrunswickNJUSA Centre for Immunobiology Blizard InstituteQueen Mary University of LondonLondonUK

Disease modifying therapies aiming to preserveβ-cell function in patients with adult-onset autoimmune type 1 diabetes are ***,we conducted a multi-centre,randomized,controlled trial to assess theβ-cell preservation effects of saxagliptin alone and saxagliptin combined with vitamin D as adjunctive therapies in adult-onset autoimmune type 1 *** this 3-arm trial,301 participants were randomly assigned to a 24-month course of the conventional therapy(metformin with or without insulin)or adjunctive saxagliptin or adjunctive saxagliptin plus vitamin D to the conventional *** primary endpoint was the change from baseline to 24 months in the fasting *** secondary endpoints included the area under the concentration-time curve(AUC)for C-peptide level in a 2-h mixed-meal tolerance test,glycemic control,total daily insulin use and safety,*** primary endpoint was not achieved in saxagliptin plus vitamin D group(P=0.18)and saxagliptin group(P=0.26).However,compared with the conventional therapy,2-h C-peptide AUC from 24 months to baseline decreased less with saxagliptin plus vitamin D(-276 pmol/L vs.-419 pmol/L;P=0.01),and not to the same degree with saxagliptin alone(-314 pmol/L;P=0.14).Notably,for participants with higher glutamic acid decarboxylase antibody(GADA)levels,the decline ofβ-cell function was much lower in saxagliptin plus vitamin D group than in the conventional therapy group(P=0.001).Insulin dose was significantly reduced in both active treatment groups than in the conventional therapy group despite all groups having similar glycemic *** conclusion,the combination of saxagliptin and vitamin D preserves pancreaticβ-cell function in adult-onset autoimmune type 1 diabetes,an effect especially efficacious in individuals with higher GADA *** results provide evidence for a novel adjunct to insulin and metformin as potential initial treatment for adult-onset type 1 diabetes.(*** identifier:NCT024

关键词： vitamin alone treatment

Highly degradable chitosan-montmorillonite (MMT) nanocomposite hydrogel for controlled fertilizer release

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Frontiers of Environmental Science & Engineering 2023年第5期17卷 1-11页

作者： Zeou Dou Maria Vitoria Bini Farias Wensi Chen Dongjing He yuhang hu Xing Xie School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA 30332USA George W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGA 30332USA School of Chemical and Biomolecular Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

Fertilizer consumption is increasing drastically along with the rapid expansion of farming in response to the ever-growing population. However, a significant portion of the nutrients in traditional fertilizers is lost during leaching and runoff causing economic loss and environmental threats. Polymer-modified controlled-release fertilizers provide an opportunity for mitigating adverse environmental effects and increasing the profitability of crop production. Here, we present a cheap and easy-to-fabricate controlled-release fertilizer excipient based on hydrogels scaffolded by safe and biodegradable chitosan and montmorillonite (MMT) nanoclays. By introducing elastic and flexible physical crosslinking induced by 2-dimensional (2D) MMT nanoflakes into the chitosan hydrogel, highly swellable and degradable chitosan-MMT nanocomposites were fabricated. The addition of MMT into the chitosan hydrogels enhanced the total release of phosphorous (P) and potassium (K), from 22.0 % to 94.9 % and 9.6% to 31.4 %, respectively, compared to the pure chitosan gel. The chitosan-MMT nanocomposite hydrogel achieved a well-controlled overall fertilizer release in soil. A total of 55.3 % of loaded fertilizer was released over 15 d with a daily release of 2.8 %. For the traditional fertilizer podwer, 89.2 % of the fertilizer was washed out during the first irrigation under the same setup. In the meantime, the nanocomposites improved the water retention of the soil, thanks to its excellent water absorbency. Moreover, the chitosan-MMT nanocomposite hydrogels exhibited high degradation of 57 % after swelling in water for 20 d. Such highly degradable fertilizer excipient poses minimal threat to the long-term fertility of the soil. The engineered Chitosan-MMT biopolymer scaffold as a controlled-release fertilizer excipient provides a promising opportunity for advancing sustainable agriculture.

关键词： Biopolymer Hydrogel Controlled-release fertilizer Nanoclay Nanocomposite

Approaching Ultimate Synthesis Reaction Rate of Ni-Rich Layered Cathodes for Lithium-Ion Batteries

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Nano-Micro Letters 2024年第10期16卷 392-402页

作者： Zhedong Liu Jingchao Zhang Jiawei Luo Zhaoxin Guo Haoran Jiang Zekun Li yuhang Liu Zijing Song Rui Liu Wei-Di Liu Wenbin hu Yanan Chen School of Materials Science and Engineering Tianjin UniversityTianjin 300072People's Republic of China School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590People's Republic of China Australian Institute of Bioengineering and Nanotechnology The University of QueenslandSt LuciaQLD 4072Australia

Nickel-rich layered oxide LiNi_(x)Co_(y)MnzO_(2)(NCM,x+y+z=1)is the most promising cathode material for high-energy lithium-ion ***,conventional synthesis methods are limited by the slow heating rate,sluggish reaction dynamics,high energy consumption,and long reaction *** overcome these chal-lenges,we first employed a high-temperature shock(HTS)strategy for fast synthesis of the NCM,and the approaching ultimate reaction rate of solid phase transition is deeply investigated for the first *** the HTS process,ultrafast average reaction rate of phase transition from Ni_(0.6)Co_(0.2)Mn_(0.2)(OH)_(2) to Li-containing oxides is 66.7(%s^(-1)),that is,taking only 1.5 *** ultrahigh heating rate leads to fast reaction kinetics,which induces the rapid phase transition of NCM *** HTS-synthesized nickel-rich layered oxides perform good cycling performances(94%for NCM523,94%for NCM622,and 80%for NCM811 after 200 cycles at 4.3 V).These findings might also assist to pave the way for preparing effectively Ni-rich layered oxides for lithium-ion batteries.

关键词： Nickel-rich layered oxides High-temperature shock Solid reaction kinetics Phase transition Reaction rate