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Design of digital calibration based on variable step size of sub-binary SAR ADC

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 62-71页

作者： Liu Wei zhao Yanke shang Shiguang School of Electronic Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China

Addressing the impact of capacitor mismatch on the conversion accuracy of successive approximation register analog-to-digital converter(SAR ADC),a 12-bit 1 MS/s sub-binary SAR ADC designed using variable step size digital calibration was *** least mean square(LMS)calibration algorithm was employed with a ramp signal used as the calibration *** errors,extracted under injected disturbances,underwent iterative training to optimize weight *** address the trade-off between conversion accuracy and speed caused by a fixed step size,a novel variable step size algorithm tailored for SAR ADC calibration was *** core circuit and layout of the SAR ADC were implemented using the Taiwan Semiconductor Manufacturing Company(TSMC)0.35μm complementary metal-oxide-semiconductor(CMOS)commercial *** of the SAR ADC calibration algorithm was conducted using Simulink,demonstrating quick convergence and meeting conversion accuracy requirements compared to fixed step size *** results indicated that the convergence speed of the LMS digital calibration algorithm with variable step size was approximately eight times faster than that with a fixed step size,also yielding a lower mean square error(MSE).After calibration,the simulation results for the SAR ADC exhibited an effective number of bit(ENOB)of 11.79 bit and a signal-to-noise and distortion ratio(SNDR)of 72.72 dB,signifying a notable enhancement in the SAR ADC performance.

关键词： successive approximation register analog-to-digital converter(SAR ADC) variable step size digital calibration disturbance technique

Interference-induced suppression of particle emission from a Bose-Einstein condensate in lattice with time-periodic modulations

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Chinese Physics B 2024年第10期33卷 153-158页

作者： Long-quan Lai zhao Li School of Science Nanjing University of Posts and TelecommunicationsNanjing 210023China School of Electronic Engineering Chengdu Technological UniversityChengdu 611730China

Emission of matter-wave jets from a parametrically driven condensate has attracted significant experimental and theoretical attention due to the appealing visual effects and potential metrological *** this work,we investigate the collective particle emission from a Bose-Einstein condensate confined in a one-dimensional lattice with periodically modulated interparticle *** give the regimes for discrete modes,and find that the emission can be distinctly *** configuration induces a broad band,but few particles are ejected due to the interference of the matter *** further qualitatively model the emission process and demonstrate the short-time *** engineering provides a way to manipulate the propagation of particles and the corresponding dynamics of condensates in lattices,and may find application in the dynamical excitation control of other nonequilibrium problems with time-periodic driving.

关键词： Bose-Einstein condensate matter-wave jet periodic modulation

Pt nanoclusters modified porous g-C_(3)N_(4)nanosheets to significantly enhance hydrogen production by photocatalytic water reforming of methanol

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Chinese Journal of Chemical Engineering 2024年第2期66卷 40-50页

作者： Yi-Fei Liang Jin-Rong Lu shang-Kun Tian Wen-quan Cui Li Liu Hebei Provincial Key Laboratory of Environmental Photocatalytic and Electrocatalytic Materials College of Chemical EngineeringNorth China University of Science and TechnologyTangshan 063210China

For the use of green hydrogen energy,it is crucial to have efficient photocatalytic activity for hydrogen generation by water reforming of methanol under mild *** attention has been paid to gC_(3)N_(4)as a promising photocatalyst for the generation of *** improve the separation of photogenerated charge,porous nanosheet g-C_(3)N_(4)was modified with Pt nanoclusters(Pt/g-C_(3)N_(4))through impregnation and following photo-induced *** catalyst showed excellent photocatalytic activity of water reforming of methanol fo r hydrogen production with a 17.12 mmol·g^(-1)·h^(-1)rate at room temperature,which was 311 times higher than that of the unmodified g-C_(3)N_(4).The strong interactions of Pt-N in Pt/g-C_(3)N_(4)constructed effective electron transfer channels to promote the separation of photogenerated electrons and holes *** addition,in-situ infrared spectroscopy was used to investigate the intermediates of the hydrogen production reaction,which proved that methanol and water eventually turn into H_(2)and CO_(2)via formaldehyde and *** study provides insights for understanding the photocatalytic hydrogen production in the water reforming of methanol.

关键词： Water reforming of methanol Photocatalysis g-C_(3)N_(4) Pt nanoclusters Hydrogen production

Approximations to Isentropic Planar Magneto-Hydrodynamics Equations by Relaxed Euler-Type Systems

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Chinese Annals of Mathematics,Series B 2024年第3期45卷 413-440页

作者： Yachun LI zhaoyang shang Chenmu WANG Liang zhao School of Mathematical Sciences CMA-ShanghaiMOE-LSC and SHL-MACShanghai Jiao Tong UniversityShanghai 200240China School of Finance Shanghai Lixin University of Accounting and FinanceShanghai 201209China School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai 200240China School of Mathematical Sciences Harbin Engineering UniversityHarbin 150001China Mathematical Modelling&Data Analytics Center Oxford Suzhou Centre for Advanced ResearchSuzhou 215123JiangsuChina

In this paper, the authors consider an approximation to the isentropic planar Magneto-hydrodynamics(MHD for short) equations by a kind of relaxed Euler-type system. The approximation is based on the generalization of the Maxwell law for nonNewtonian fluids together with the Maxwell correction for the Ampe`re law, hence the approximate system becomes a first-order quasilinear symmetrizable hyperbolic systems with partial dissipation. They establish the global-in-time smooth solutions to the approximate Euler-type equations in a small neighbourhood of constant equilibrium states and obtain the global-in-time convergence towards the isentropic planar MHD equations. In addition, they also establish the global-in-time error estimates of the limit based on stream function techniques and energy estimates for error variables.

关键词： Planar MHD equations Relaxation limits Global convergence Stream function

Link between periodontitis and diabetic retinopathy:Inflammatory pathways and clinical implications

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World Journal of Diabetes 2024年第9期15卷 1842-1846页

作者： Yu zhao quan-quan Shen Geriatric Medicine Center Department of EndocrinologyZhejiang Provincial People’s Hospital(Affiliated People’s Hospital)Hangzhou Medical CollegeHangzhou 310014Zhejiang ProvinceChina Urology and Nephrology Center Department of NephrologyZhejiang Provincial People’s Hospital(Affiliated People’s HospitalHangzhou Medical College)Hangzhou 310014Zhejiang ProvinceChina Department of Nephrology Zhejiang Provincial People’s Hospital Bijie HospitalBijie 551700Guizhou ProvinceChina

The bidirectional relationship between periodontitis and type 2 diabetes mellitus has been ***,the underlying molecular mechanisms remain *** retinopathy(DR)is an important complication of diabetes,but there are few studies on the relationship between DR and periodontitis,especially on the intrinsic inflammatory pathway *** article reviews the latest clinical data on how diabetes promotes susceptibility to periodontitis from the epidemiological and molecular perspectives,with a special focus on the key roles of systemic inflammation and endothelial dysfunction in the interplay between DR and *** of the intertwined pathogenesis of DR and periodontitis can better guide the development of comprehensive management strategies for glycemic control and periodontal health,with the aim of mitigating the progression of DR and enhancing overall well-being.

关键词： Type 2 diabetes mellitus Diabetic retinopathy Microvascular complications Periodontitis Systemic inflammation Endothelial dysfunction

Hydrodynamic Performance of An Integrated System of Breakwater and A Multi-Chamber OWC Wave Energy Converter

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China Ocean Engineering 2024年第4期38卷 543-556页

作者： NING De-zhi ZHANG Xiang-yu WANG Rong-quan zhao Ming State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China Dalian Key Laboratory of Offshore Renewable Energy Dalian University of TechnologyDalian 116024China School of Computing Engineering and MathematicsUniversity of Western SydneyPenrith NSW 2751Australia

A multi-chamber oscillating water column wave energy converter(OWC-WEC)integrated to a breakwater is *** hydrodynamic characteristics of the device are analyzed using an analytical model based on the linear potential flow theory.A pneumatic model is employed to investigate the relationship between the air mass flux in the chamber and the turbine *** effects of chamber width,wall draft and wall thickness on the hydrodynamic performance of a dual-chamber OWC-WEC are *** results demonstrate that the device,with a smaller front wall draft and a wider rear chamber exhibits a broader effective frequency *** device with a chamber-width-ratio of 1:3 performs better in terms of power ***,results from the analysis of a triplechamber OWC-WEC demonstrate that reducing the front chamber width and increasing the rearward chamber width can improve the total performance of the *** the number of chambers from 1 to 2 or 3 can widen the effective frequency bandwidth.

关键词： oscillating water column power extraction efficiency potential flow theory wave energy converter multi-chamber

Microstructure and properties of LZQT600-3 HCCDIBs for plunger pump cylinder

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China Foundry 2024年第2期21卷 197-204页

作者： Chun-jie Xu Yuan-ying Jin Dong Ma Zhen zhao Jia-wei Qi shang Sui Xiang-quan Wu Can Guo Zhong-ming Zhang Yong-hui Liu Dan Shechtman School of Materials Science and Engineering Xi'an University of TechnologyXi'an 710048China Xi'an Shechtman Nobel Prize New Materials Institute Xi'an 710048China Tongchuan Huazhu Precision Technology Co. Ltd.Tongchuan 727100ShaanxiChina Faculty of Materials Science and Engineering Technion-Israel Insititue of TechnologyHaifa 3200003Israel

It is important to improve the comprehensive performance of the ductile iron bars(DIBs)for the cylinder block of the extra high pressure hydraulic plunger pump and accelerate the industrial *** this work,the LZQT600-3 DIBs with the diameter of 145 mm were prepared by the horizontal continuous casting(HCC)process,that is,LZQT600-3 *** microstructure and room temperature tensile properties of different sections[left-edge(surface layer),left-1/2R(left half of the radius),and the center of the HCCDIBs]were *** results show that the spheroidization of LZQT600-3 HCCDIBs matrix from the left-edge,left-1/2R to the center is at nodulizing grade II and *** the cooling rate gradually decreases from surface to the center of the HCCIBs,the number of spheroidized graphite is gradually reduced,the size is gradually increased,the shape factor is decreased,and the pearlite content and lamellate spacing are *** the horizontal direction of the section,the hardness of the material is distributed symmetrically around the center of the *** the vertical direction,the hardness distribution in the center of the HCCDIBs is asymmetrical due to the gravity during the solidification ***,the microstructure in the lower part of the section solidifies relatively *** left-edge has the best tensile mechanical properties,and the ultimate tensile strength,yield tensile strength and elongation are 597.3 MPa,418.5 MPa and 9.6%,*** tensile fracture belongs to the ductile-brittle hybrid *** comprehensive performances of LZQT600-3 HCCDIBs meet the actual application requirements of ultra-high pressure hydraulic plunger pump cylinder.

关键词： horizontal continuous casting(HCC) nodular cast iron ductile iron bars microstructure mechanical properties

The influence of silica on reaction rates and molecular hydrogen(H_(2))generation during olivine hydrothermal alteration

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Science China Earth Sciences 2024年第1期67卷 222-233页

作者： Ruifang HUANG Weidong SUN Xing DING Yusheng zhao Yibing LI Xiuqi shang CAS Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China SUSTech Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen 518055China Center of Deep Sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Institue of Geology Chinese Academy of Geological SciencesBeijing 100037China

Hydrothermal alteration of olivine greatly influences geodynamics and the recycling of volatiles(such as water and carbon)in subduction *** is an important component of geological fluids,and its influence on the hydrothermal alteration of olivine remains poorly *** this study,we performed experiments at 300–515℃ and 3.0 kbar(1 bar=10^(5)Pa)by reacting well homogenized mixtures of olivine and silica powders with saline solutions(0.5 mol L^(−1)NaCl).Silica greatly influences the reaction pathways,reaction rates,and molecular hydrogen(H_(2))formation during olivine hydrothermal *** experiments at 300℃ and 3.0 kbar with mixtures of olivine and 10 wt%silica,olivine was replaced by serpentine and *** proportions of serpentine and talc were determined according to standard curves based on infrared spectroscopy *** 6.5%serpentine and 12%talc were produced after an experimental duration of 7 days,which had no change after a longer period(14 days).Compared to the kinetics in silica-free systems,the rates of olivine hydrothermal alteration in experiments with 10 wt%silica are much *** overall reaction is:4.5Forsterite+5.5SiO_(2),aq+4H_(2)O=Serpentine+*** the addition of more silica(20 wt%and 40 wt%),olivine was transformed into *** rates of reaction were much faster,e.g.,for experiments with olivine and 20 wt%silica,43%of talc was produced after 14 days,which increased to 77%for experiments with 40 wt%silica over the same *** overall reaction is:3Forsterite+5SiO_(2),aq+2H_(2)O=*** experiments at 400–505℃ and 3.0 kbar,the promoting effect of silica on olivine hydrothermal alteration was also observed,which is closely associated with a decrease in Gibbs free energies of olivine hydrothermal *** 300℃ and 3.0 kbar,silica decreased H_(2)formed during olivine hydrothermal alteration by around an order of magnitude,resulting in an increase in oxygen *** on measured H_(2),we calibrated ox

关键词： Olivine hydrothermal alteration Silica Serpentinization Hydrogen Serpentine

A high-performance lithium anode based on N-doped composite graphene

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Rare Metals 2024年第3期43卷 1030-1036页

作者： Can Jiao Hao-Bo Sun Li Zhang shang-Qian zhao Guo-Yao Pang Chun-Rong zhao Shi-Gang Lu General Research Institute for Nonferrous Metals Beijing100088China China Automotive Battery Research Institute Co.Ltd Beijing101407China

Lithium(Li)metal is the most promising electrode for next-gene ration rechargeable *** order to push the commercialization of the lithium metal batteries,a kind of nitrogen(N)-doped composite graphene(NCG)adopted as the Li plating host was prepared to regulate Li metal nucleation and suppress dendrite ***,a new kind of sandwich-type composite lithium metal(STCL)electrode was developed to improve its *** STCL electrode can be used as convenient as a piece of Li foil but no dendrite *** a symmetric battery,the STCL electrode cycled for more than 4500 h with the overpotential of less than 40 *** due to the creative design,the STCL promises the Li-S battery with a prolonged cycling lifespan.

关键词： Lithium metal anode Lithiophilic N-doped composite graphene Sandwich-type composite lithium metal electrode