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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 98-113页

作者： LIU zai-ming GENG Bing-zhen WANG shi-jie School of Mathematics and Statistics Central South UniversityChangsha 410083China School of Big Data and Statistics Anhui UniversityHefei 230601China

Consider a nonstandard continuous-time bidimensional risk model with constant force of interest,in which the two classes of claims with subexponential distributions satisfy a general dependence structure and each pair of the claim-inter-arrival times is arbitrarily *** some mild conditions,we achieve a locally uniform approximation of the finite-time ruin probability for all time horizon within a finite *** we further assume that each pair of the claim-inter-arrival times is negative quadrant dependent and the two classes of claims are consistently-varying-tailed,it shows that the above obtained approximation is also globally uniform for all time horizon within an infinite interval.

关键词： bidimensional risk model asymptotic formula subexponential distribution consistently varying tail ruin probability

Origin of the Dashuigou independent tellurium deposit at Qinghai–Xizang Plateau: constraints from the light stable isotopes C, O, and H

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Acta Geochimica 2024年第2期43卷 385-398页

作者： Jianzhao Yin Yuhong Chao Haoyu Yin Hongyun shi Shoupu xiang Wuhan Institute of Technology Wuhan 430074China College of Earth Sciences Jilin UniversityChangchun 130061China Ganzhongnan Institute of Geology and Mineral Exploration Nanchang 330002China Guinea Westfi eld Mining Company-Sarlu Jinzhong 031300China Orient Resources Ltd. RichmondB.C.V7E 1M8Canada Silvercorp Metals Inc. Beijing 100027China

By studying the light isotopic compositions of carbon,oxygen,and hydrogen,combined with previous research results on the ore-forming source of the deposit,the authors try to uncover its metallogenic *** δ^(18)O and δ^(13)C isotope signatures of dolomite samples vary between 10.2 and 13.0‰,and between−7.2 and−5.2‰,respectively,implying that the carbon derives from the upper mantle.δD and δ^(18) O of quartz,biotite,and muscovite from diff erent ore veins of the deposit vary between−82 and−59‰,and between 11.6 and 12.4‰,respectively,implying that the metallogenic solutions are mainly *** to the relevant research results of many isotope geologists,the fractionation degree of hydrogen isotopes increases as the depth to the Earth’s core increases,and the more diff erentiated the hydrogen isotopes are,the lower their values will *** other words,mantle-derived solutions can have extremely low hydrogen isotope *** means that the δD‰ value−134 of the pyrrhotite sample numbered SD-34 in this article may indicate mantle-derived oreforming fl uid of the *** formation of the Dashuigou tellurium deposit occurred between 91.71 and 80.19 Ma.

关键词： Carbon oxygen and hydrogen isotopes Origin Independent tellurium deposit The Qinghai–Xizang Plateau

A novel thermally-stable single-phase phosphor Ca_(2)InTaO_(6):Dy^(3+)for NUV-excited white LEDs

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Journal of Rare Earths 2024年第10期42卷 1855-1864页

作者： Jian Hu Ruirui Cui Jun Zhang Peng Linghu Youzhen shi xiang Guo Key Laboratory of Micro-Nano-Electronics and Software Technology of Guizhou Province College of Big Data and Information EngineeringGuizhou UniversityGuiyang550025China College of Computer and Information Engineering Guizhou University of CommerceGuiyang550014China

The work focuses on the utilization of the conventional solid-state sintering procedure to synthesize white phosphors Ca_(2)InTaO_(6):xDy^(3+)(0.02≤x≤0.12).Utilizing X-ray diffraction,the phase structure of samples was examined,and the crystal structure was refined using the Rietveld method.A scanning electron microscope was used to analyze the microstructure of ***-principles calculations confirm that the indirect bandgap of Ca_(2)InTaO_(6)is 3.786 eV,The luminous properties and energy transfer mechanism of Ca_(2)InTaO_(6):xDy^(3+)were studied using photoluminescence ***~4F_(9/2)→~6H_(13/2)transition of Dy^(3+)ions is responsible for the greatest emission peak,which was measured at 575 *** to research,the lifespan falls as the concentration of Dy^(3+)doping amount rises because of frequent interaction and ene rgy transfer between Dy^(3+)*** correlated color temperature of the WLEDs packaged with Ca_(2)InTaO_(6):0.08Dy^(3+)is 4677 K and CIE 1931 chromaticity coordinates are(0.3578,0.3831).Meantime,the phosphor also shows outstanding te mperature stability property,which maintains 83.8%of its initial emission intensity at 450 K(activation energy of 0.1467 eV).The W-LEDs retain their performance for 100 min when powered at 3.4 V voltage and 600 mA current,demonstrating the packed W-LEDs'sustaine d operation at high temperatures.

关键词： Ca_(2)InTaO_(6):Dy^(3+)phosphors Thermal stability Photoluminescence W-LEDs Thermal imaging Rare earths

A novel subset assignment and matching method for DIC measurement of complex deformation in aircraft braking process

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Chinese Journal of Aeronautics 2024年第8期37卷 373-387页

作者： Xin shi xiang GUO Tao SUO Yingtao YUAN Hongli HE Zhiyong REN School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China International Research Laboratory of Impact Dynamics and its Engineering Application Xi’an 710072China Institute of Extreme Mechanics Northwestern Polytechnical UniversityXi’an 710072China Chinese Flight Test Establishment Xi’an 710089China

This paper proposes a measurement method related to the braking deformation of a complex *** the braking process,the deformation of the wheel includes large amounts of movement,vibration,warping,and distortion.A novel subset assignment and correlation method is proposed to measure the complex *** proposed method can greatly improve the accuracy and stability of the calculation of complex deformations by simplifying the complex deformation into translational deformations in logarithmic coordinate *** to the simulation and actual experiments,the proposed method can be utilized to measure the deformations of up to 100%tensile strain under complex *** to the accuracy verification experiment,the error of the proposed method is less than 50 *** results show that the proposed method can effectively carry out structural deformation measurement in the complex motion and deformation *** proposed method has great significance for structural performance analysis and optimization design considering complex motion and deformation.

关键词： Complex deformation Measurement Digital image correlation Aircraft braking Deformation field

Six million Q factor micro fused silica shell resonator with teeth-like tines released by femtosecond laser-assisted chemical etching

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Science China(Technological Sciences) 2024年第6期67卷 1923-1932页

作者： ZHAO Tao shi Yan LU Kun XI xiang WU XueZhong XIAO DingBang College of Intelligence Science and Engineering National University of Defense TechnologyChangsha410073China

The quality factor(Q factor)is a crucial performance parameter for *** this paper,a novel release method for highquality micro fused silica shell resonators with teeth-like tines with good surface morphology is *** method is based on femtosecond laser-assisted chemical ***,the optimal energy range of femtosecond laser modification is obtained through mechanism ***,the optimal parameters for a straight line and arc pattern are determined by optimizing the average output power,processing speed,and processing *** results demonstrate why edge breakage in rounded corners is easy under different ***,according to these conclusions,the processing is performed on a micro fused silica shell resonator with a Q factor exceeding 6 *** addition,subsurface damage is rare throughout the fabrication process,and the surface roughness of the released cross section reaches the nanometer *** improved Q factor helps suppress mechanical thermal noise and reduce zero bias and zero bias drift,constituting the primary method for enhancing the performance of the resonant gyroscope.

关键词： micro hemispherical resonator fused silica laser-assisted chemical etching quality factor

Conversion of a single-layer ANN to photonic SNN for pattern recognition

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Science China(Information Sciences) 2024年第1期67卷 261-270页

作者： Yanan HAN Shuiying xiang Tianrui ZHANG Yahui ZHANG Xingxing GUO Yuechun shi State Key Laboratory of Integrated Service Networks State Key Discipline Laboratory of Wide Bandgap Semiconductor TechnologyXidian University Yongjiang Laboratory

This work presents a complete conversion scheme for photonic spiking neural networks(SNNs).We verified that the output of an artificial neural network(ANN) trained with the simulated optical activation function can be directly converted into the spike rate of a photonic spiking neuron *** reveal the feasibility of hardware implementation,we considered the effects of different bit precisions of data and weight,noise level,and bias current mismatch on the converted *** proposed scheme was evaluated using the Deterding vowel,IRIS,TIDIGITS,and MNIST datasets for pattern recognition,and achieved mean accuracies of 95.80%,98.67%,96.19%,and 92.33%,*** proposed scheme can convert an ANN into a photonic SNN with almost no precision loss,and the performance was comparable to that of an ANN trained with the rectified linear unit *** proposed scheme can enable the high-performance implementation of photonic SNNs.

关键词： photonic SNN conversion optical computing pattern recognition artificial neural network

Effect of nursing on postoperative respiratory function and mental health of lung cancer patients

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World Journal of Clinical Cases 2024年第5期12卷 922-930页

作者： xiang Yang Dan Yin shi-Qing Chen Department of Rehabilitation The First People's Hospital of Jiangxia DistrictWuhan(Union Jiangnan Hospital Huazhong University of Science and Technology)Wuhan 430200Hubei ProvinceChina Department of Intensive Care The First People's Hospital of Jiangxia DistrictWuhan(Union Jiangnan Hospital Huazhong University of Science and Technology)Wuhan 430200Hubei ProvinceChina Department of Neurology The First People's Hospital of Jiangxia DistrictWuhan(Union Jiangnan Hospital Huazhong University of Science and Technology)Wuhan 430200Hubei ProvinceChina

BACKGROUND Both pulmonary rehabilitation training and psychological care have been shown to have a positive effect on the postoperative recovery of patients with lung ***,few studies have combined the two to explore their combined ***,this study aimed to investigate the effects of pulmonary rehabil-itation training combined with psychological care on postoperative respiratory function and mental health in lung cancer *** To investigate effect of nursing on postoperative respiratory function and mental health of lung cancer *** 122 cases of lung cancer patients who underwent surgical treatment in our hospital and were treated in our department from January 2022 to April 2023 were selected and randomly divided into the control group and observation *** control group performed the routine care *** obser-vation group was given pulmonary rehabilitation training and psychological care based on conventional nursing *** expiratory volume,forced vital *** ventilatory volume(MVV)in one second was measured,and the patient's 6-min walking distance and dyspnoea index scale were used to assess the patient's respiratory *** Connor-Davidson resilience scale(CD-RISC),self-rating anxiety scale(SAS),and self-rating depression scale(SDS)were used to evaluate the mental health of the *** There was no difference between the two groups regarding age,gender,education level,surgical procedure,type of pathology,and treatment(P>0.05).After treatment,MVV,6-min walking distance,toughness,strength,optimism,and total CD-RISC scores were significantly higher in the observation group(P<0.05),dyspnoea scores,SAS,and SDS scores were substantially lower in the control group compared to the observation group(P<0.05).CONCLUSION Pulmonary rehabilitation training combined with psychological care for patients after lung cancer resection could improve lung function,enhance daily activities,e

关键词： Pulmonary rehabilitation training Psychological care Lung cancer Postoperative care Respiratory function

Influence of ion species on extraction characteristicsof mixed ion beams

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Chinese Physics B 2024年第9期33卷 444-449页

作者： Ao Xu Pingping Gan xiang Wan Yuanjie shi Institute of Electronic Engineering China Academy of Engineering PhysicsMianyang 621999China

The spatial distributions of different kinds of ions are usually not completely the same in the process of *** order to study the reason for the different characteristics of ion extraction, a simplified simulation model of Cu+ andCr+ ions extraction process was established by 2D3V (two-dimensional in space and three- dimensional in velocity space)particle-in-cell (PIC) method. The effects of different extraction voltages from 0 V to 500 V on the density distribution ofCu+ and Cr+ ions and the change of plasma emission surface were analyzed. On the basis of this model, the ion densitydistribution characteristics of Cu+ ions mixed with Li+, Mg+, K+, Fe+, Y+, Ag+, Xe+, Au+, and Pb+ ions respectivelyunder 200-V extraction voltage are further simulated, and it is revealed that the atomic mass of the ions is the key reason fordifferent ion density distributions when different kinds of ions are mixed and extracted, which provides support for furtherunderstanding of ion extraction characteristics.

关键词： extraction ion species density distribution atomic mass

Solvent extraction of scandium from leaching solution of red mud roasted with ammonium sulfate using D2EHPA/TBP

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Journal of Rare Earths 2024年第10期42卷 1943-1949页

作者： Fucheng Li Xinsheng Li Lei shi xiang Li Duoqiang Liang Yuezhou Wei Toyohisa Fujita School of Resources Environment and MaterialsGuangxi UniversityNanning530004China State Key Laboratory of Featured Metal Materiais and Life-for Composite Structures Guangxi UniversityNanning530004China School of Nuclear Science and Technology University of South ChinaHengyang421001China

Red mud is an important secondary resource for scandium *** red mud leaching solution containing scandium in this study was derived from environmentally friendly ammonium sulfate roasting and water leaching process.A synergistic extraction with a mixture of di(2-ethylhexyl)phosphate acid(D2EHPA)and tributyl phosphate(TBP)for recovery of scandium from red mud leaching solution is *** effects of D2EHPA concentration,H_(2)SO_(4)concentration,rare earth elements,dosage of TBP,phase ratio(A/O),contact time and H_(2)O_(2)concentration on scandium extraction were *** results show that more than 99%scandium is extracted under the optimal conditions while Fe,Al,Ti,Ca and rare earth elements(Ce,Y,La,Nd,Er,etc.)are hardly *** stripping efficiency of Sc reaches above 92.37%under the optimal stripping conditions of 5 mol/L NaOH with an A/O of 1 at 90℃for 30 *** proposed technology could provide an effective method for extraction of scandium from red mud leaching solution.

关键词： Scandium Red mud leaching solution D2EHPA/TBP Solvent extraction Rare earths

Silencing of peroxiredoxin 2 suppresses proliferation and Wnt/β-catenin pathway,and induces senescence in hepatocellular carcinoma

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Oncology Research 2024年第1期32卷 213-226页

作者： XUEGANG YANG XIANHONG xiang GUOHUI XU shi ZHOU TIANZHI AN ZHI HUANG Department of Interventional Radiology Sichuan Cancer Hospital and InstituteSichuan Cancer CenterSchool of MedicineUniversity of Electronic Science and Technology of ChinaRadiation Oncology Key Laboratory of Sichuan ProvinceChengdu610041China Department of Interventional Radiology The First Affiliated Hospital of Sun Yat-sen UniversityGuangzhou510080China Department of Interventional Radiology Affiliated Hospital of Guizhou Medical UniversityGuiyang550004China School of Basic Medical Science Guizhou Medical UniversityGuiyang550002China

Hepatocellular carcinoma(HCC),a common malignancy worldwide,still lacks effective clinical *** study aimed to investigate the oncogenes that affect the progression of HCC and their possible *** our study,we initially confirmed a higher level of PRDX2 in the bile of HCC patients compared to those with choledocholithiasis by 2-DE,LC-MS,and ***,we demonstrated the high expression of peroxiredoxin 2(PRDX2)in HCC based on the TCGA database and clinical sample ***,PRDX2 overexpression enhanced the viability of HCC *** PRDX2 silencing induced senescence of HCC *** vivo,knockdown of PRDX2 significantly reduced the weight of xenograft ***2 also was found to activate the Wnt/β-catenin pathway by inducingβ-catenin nuclear ***,we proved that silencing PRDX2 could inhibit proliferation and Wnt/β-catenin pathway while promoting senescence in HCC cells.

关键词： Peroxiredoxin 2 Hepatocellular carcinoma Wnt/β-catenin pathway Senescence Proliferation