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Regularized automatic frequency response function acquisition of a milling robot operating in a high-dimensional workspace

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Science China(Technological Sciences) 2024年第6期67卷 1783-1797页

作者： LUO WenLong TANG XiaoWei ma Tao GUO QiuShuang XU YanYan YUAN Xing ZHANG lei maO XinYong School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan430074China State Key Laboratory of Smart manufacturing for Special Vehicles and Transmission System Baotou014030China Wuhan Heavy Duty machine Tool Group Corporation Wuhan430205China

Because robotic milling has become an important means for machining significant large parts,obtaining the structural frequency response function(FRF)of a milling robot is an important basis for machining process ***,because of its articulated serial structure,a milling robot has an enormous number of operating postures,and its dynamics are affected by the motion *** accurately obtain the FRF in the operating state of a milling robot,this paper proposes a method based on the structural modification *** the traditional excitation method,the proposed method uses robot joint motion excitation instead of hammering excitation to realize *** address the problem of the lack of information brought by motion excitation,which leads to inaccurate FRF amplitudes,this paper derives the milling robot regularization theory based on the sensitivity of structural modification,establishes the modal regularization factor,and calibrates the FRF *** to the commonly used manual hammering experiments,the proposed method has high accuracy and reliability when the milling robot is in different *** the measurement can be performed directly and automatically in the operation state,and the problem of inaccurate amplitudes is solved,the proposed method provides a basis for optimizing the machining posture of a milling robot and improving machining efficiency.

关键词： milling robot structural dynamics frequency response function automatic identification modal regularization factor high-dimensional workspace

Effects of Lactobacillus paracasei N1115 on gut microbial imbalance and liver function in patients with hepatitis B-related cirrhosis

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World Journal of Gastroenterology 2024年第11期30卷 1556-1571页

作者： Yan-Chao Hu Xiang-Chun Ding Hui-Juan Liu Wan-Long ma xue-Yan Feng Li-Na ma Department of Infectious Disease General Hospital of Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina Infectious Disease Clinical Research Center of Ningxia Yinchuan 750004Ningxia Hui Autonomous RegionChina

BACKGROUND Hepatitis B cirrhosis(HBC)is a chronic disease characterized by irreversible diffuse liver damage and aggravated by intestinal microbial imbalance and metabolic *** the relationship between certain single probiotics and HBC has been explored,the impact of the complex ready-to-eat Lactobacillus paracasei N1115(LP N1115)supplement on patients with HBC has not been *** To compare the changes in the microbiota,inflammatory factor levels,and liver function before and after probiotic treatment in HBC *** This study included 160 HBC patients diagnosed at the General Hospital of Ningxia Medical University between October 2018 and December *** were randomly divided into an intervention group that received LP N1115 supplementation and routine treatment and a control group that received routine treatment *** samples were collected at the onset and conclusion of the 12-wk intervention *** structure of the intestinal microbiota and the levels of serological indicators,such as liver function and inflammatory factors,were *** Following LP N1115 intervention,the intestinal microbial diversity significantly increased in the intervention group(Pmatory factors(Pmatory factor levels.

关键词： Hepatitis B cirrhosis N1115 ready-to-eat lactobacillus Inflammation Liver function Lachnospiraceae incertae sedis Probiotic

Changes of the peripapillary vascular parameters inpremature infants without retinopathy of prematurityusing U-net segmentation

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1453-1461页

作者： Shuai Liu lei Liu Cui-Xia ma Liu-Hui Huang Bin Li School of Information Science and Technology University of Science and Technology of ChinaHefei 230022Anhui ProvinceChina Zhejiang Lab Hangzhou 311121Zhejiang ProvinceChina Eye Institute Affiliated Hospital of Nantong UniversityMedical School of Nantong UniversityNantong 226006Jiangsu ProvinceChina Anhui Province maternity and Child Health Hospital Maternity and Child Health Hospital Affiliated to Anhui Medical UniversityHefei 230001Anhui ProvinceChina Department of Ophthalmology Tenth People’s Hospital Affiliated with Shanghai Tongji University School of MedicineShanghai 200072China

AIM:To quantitatively assess the changes in mean vascular tortuosity(mVT)and mean vascular width(mVW)around the optic disc and their correlation with gestational age(GA)and birth weight(BW)in premature infants without retinopathy of prematurity(ROP).METHODS:A single-center retrospective study included a total of 133(133 eyes)premature infants[mean corrected gestational age(CGA)43.6wk]without ROP as the premature group and 130(130 eyes)CGA-matched fullterm infants as the control *** peripapillary mVT and mVW were quantitatively measured using computerassisted ***:Premature infants had significantly higher mVT(P=0.0032)and lower mVW(P=0.0086)by 2.68(10^(4) cm^(-3))and 1.85μm,*** analysis with GA showed significant differences(P=0.0244)in mVT between the early preterm and middle to late preterm groups,but the differences between mVW were not significant(P=0.6652).The results of the multiple linear regression model showed a significant negative correlation between GA and BW with mVT after adjusting sex and CGA(P=0.0211 and P=0.0006,respectively).For each day increase in GA at birth,mVT decreased by 0.1281(10^(4) cm^(-3))and for each 1 g increase in BW,mVT decreased by 0.006(10^(4) cm^(-3)).However,GA(P=0.9402)and BW(P=0.7275)were not significantly correlated with ***:Preterm birth significantly affects the peripapillary vascular parameters that indicate higher mVT and narrower mVW in premature infants without *** in these parameters may provide new insights into the pathogenesis of ocular vascular disease.

关键词： premature infants retinopathy of prematurity retinal vessels parameter computer-assisted techniques

Simulation design of thin film lithium niobate electro-optic modulator with bimetallic layer electrodes

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Optoelectronics Letters 2024年第6期20卷 339-345页

作者： WU Qiulin FENG Xinkai CHEN Jiaying ma lei CHEN Huaixi LIANG Wanguo Fujian Institute of Research on the Structure of matter Chinese Academy of SciencesFuzhou 350108China University of Chinese Academy of Sciences Beijing 100059China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China1

Thin-film lithium niobate electro-optical modulator will become the key device in the future optical communication,which has the advantages of high modulation rate,low half-wave voltage,large bandwidth,and easy integration compared with conventional bulk lithium niobate ***,because the electrode gap of the lithium niobate film modulator is very narrow,when the microwave frequency gets higher,it leads to higher microwave loss,and the electro-optical performance of the modulator will be greatly ***,we propose a thin film lithium niobate electro-optic modulator with a bimetallic layer electrode structure to achieve microwave loss less than 8 dB/cm in the range of 200 GHz,exhibiting a voltage-length product of 1.1 V·cm and a 3 dB electro-optic bandwidth greater than 160 ***-speed data transmission test has been performed,showing good performance.

关键词： Simulation design of thin film lithium niobate electro-optic modulator with bimetallic layer electrodes

Bias distribution and regulation in photoelectrochemical overall water-splitting cells

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National Science Review 2024年第4期11卷 141-150页

作者： Kun Dang Siqin Liu lei Wu Daojian Tang Jing xue Jiaming Wang Hongwei Ji Chuncheng Chen Yuchao Zhang Jincai Zhao Key Laboratory of Photochemistry CAS ResearchEducation Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

The water oxidation half-reaction at anodes is always considered the rate-limiting step of overall water splitting（OWS）,but the actual bias distribution between photoanodes and cathodes of photoelectro chemical（PEC） OWS cells has not been investigated *** this work,we find that,for PEC cells consisting of photoanodes（nickel-modified n-Si [Ni/n-Si] and α-Fe2O3） with low photovoltage(Vph 1V,the bias required for cathode activation can be significantly reduced,exhibiting a kinetics-controlled *** investigations show that the bias distribution can be regulated by tuning the electrolyte pH and using alternative half-reaction ***,a volcano plot is presented for the rational design of the overall reactions and unbiased PEC *** by this,an unbiased PEC cell consisting of a simple Ni/n-Si photoanode and Pt cathode is assembled,delivering a photo current density of 5.3±0.2 ma cm-2.

关键词： photoelectrochemistry overall reaction cell bias distribution photoanode water splitting

Breaking the efficiency limitations of dissipative Kerr solitons using nonlinear couplers

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 88-94页

作者： Ming Li Xiao-Xiao xue Yan-lei Zhang Xin-Biao Xu Chun-Hua Dong Guang-Can Guo Chang-Ling Zou CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China CAS Centerfor Excellence in Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China Department of Electronic Engineering Beijing National Research Center for Information Science and TechnologyTsinghua University Beijing 100084China

Dissipative Kerr solitons(DKS) have long been suffering from poor power conversion efficiency when driven by continuous-wave lasers. By deriving the critical coupling condition of a multimode nonlinear optics system in a generalized theoretical framework,two efficiency limitations of the conventional pump method of DKS are revealed: the effective coupling rate is too small and is also power-dependent. A general approach is provided to resolve this challenge by introducing two types of nonlinear couplers to couple the soliton cavity and CW input through nonlinear processes. The collective coupler opens multiple coupling channels and the self-adaptive coupler builds a power-independent effective external coupling rate to the DKS for approaching the generalized critical coupling condition, which promises near-unity power conversion efficiencies. For instance, a conversion efficiency exceeding 90% is predicted for aluminum nitride microrings with a nonlinear coupler utilizing second-harmonic generation. The mechanism applies to various nonlinear processes, including Raman and Brillouin scattering, and thus paves the way for micro-solitons toward practical applications.

关键词： Kerr frequency comb conversion efficiency nonlinear coupler

Effects of Biochar Inoculation with Bacillus megaterium on Rice Soil Phosphorus Fraction Transformation and Bacterial Community Dynamics

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Rice science 2024年第4期31卷 361-365,I0001-I0003页

作者： YU Keru xue Zhaokun FANG Xianzhi ma Jiawei WANG Yongjun LIU Dan YE Zhengqian State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300China Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province Zhejiang A&F UniversityHangzhou 311300China Department of Forest Protection College of Forestry and BiotechnologyZhejiang A&F UniversityHangzhou 311300China

Rice husk biochar inoculated with Bacillus megaterium(BM)(referred to as BM-inoculated biochar, BMB) and uninoculated rice husk biochar(RHB) were added to soil at two rates(0.5%, as BMB1 and RHB1, respectively, and 1.0%, as BMB2 and RHB2, respectively) in an incubation experiment to comprehensively evaluate their effects on basic soil properties, phosphorus(P) fractions, bacterial community composition, and P-cycling genes.

关键词： soil comprehensive Transformation

Design,Testing and Control of a magnetorheological Damper for Knee Prostheses

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Journal of Bionic Engineering 2024年第4期21卷 1788-1800页

作者： Hounan Song Yu Cao Wei Chen lei Ren Yongxin ma Kunyang Wang Xu Wang Yao Zhang Luquan Ren Key Laboratory of Bionic Engineering Ministry of EducationJilin UniversityChangchun130022People’s Republic of China Department of Mechanical Aerospace and Civil EngineeringThe University of ManchesterManchesterM139PLUK

This study aims to develop a magnetorheological(MR)damper for semi-active knee prostheses to restore the walking ability of transfemoral *** core dimensions of the MR damper were determined via theoretical magnetic field calculations,and the theoretical relationship between current and joint torque was derived through electromagnetic ***,a physical prototype of the semi-active prosthetic knee equipped with the MR damper was *** on the data obtained from angle sensor,pressure sensor(loadcell),and inertial measurement unit(IMU)on the prosthesis,a matching control algorithm is *** joint torque of the MR damper can be adaptively adjusted according to the walking speed of the amputee,allowing the amputee to realize a natural *** effectiveness of the control program was verified by the ADAMS and maTLAB *** results of the test and simulation show that the MR damper can provide sufficient torque needed for normal human activities.

关键词： Semi-active knee prosthesis magnetorheological damper Theoretical analysis ADAMS and maTLAB co-simulation

A general synthetic strategy for N, P co-doped graphene supported metal-rich noble metal phosphides for hydrogen generation

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Green Energy & Environment 2024年第1期9卷 152-162页

作者： Jingwen ma Xiang Li Guangyu lei Jun Wang Juan Wang Jian Liu Ming Ke Yang Li Chunwen Sun School of Chemical and Environmental Engineering China University of Mining and Technology(Beijing)Beijing100083China State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Lab of Advanced Nano-structures&Transfer Processes Department of Chemical EngineeringTianjin UniversityTianjin300354China PetroChina Planning and Engineering Institute Beijing100083China

The exploitation of electrocatalysts with high activity and durability for HER is desirable for future energy systems,but it is still a *** have attracted increasing attentions,but the preparation process often needs toxic regents or dangerous reaction ***,we develop a general green method to fabricate metal-rich NMPs anchored on NPG through pyrolyzing DNA cross-linked *** obtained Ru_(2) P-NPG exhibits an ultrasmall overpotential of 7 mV at 10 ma cm^(2) and ultralow Tafel slope of 33 mV dec^(-1) in 1.0 mol L?1 KOH,even better than that of commercial Pt/*** addition,Ru 2 P-NPG also shows low overpotentials of 29 and 78 mV in 0.5 mol L^(-1) H_(2)SO_(4) and 1.0 mol L^(-1) PBS,*** superior activity can be attributed to the ultrafine dispersion of Ru 2 P nanoparticles for more accessible sites,more defects formed for abundant active sites,the two-dimensional plane structure for accelerated electron transfer and mass transport,as well as the regulation of electron distribution of the ***,the synthetic method can also be applied to prepare other metal-rich noble metal phosphides(Pd_(3)P-NPG and Rh_(2)P-NPG),which also exhibits high activity for *** work provides an effective strategy for designing NMP-based electrocatalysts.

关键词： Noble metal phosphides Electrocatalyst Deoxyribonucleic acid Hydrogen evolution pH universal