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Journal of Rare Earths 2025年第1期43卷 153-161,I0006页

作者： Xiangkang Peng Fapeng yu State Key Laboratory of crystal Materials Institute of Crystal MaterialsShandong UniversityJinan250100China

The new component of melilite type crystal caNdAl_(3)O_(7)(cNA)was grown by the czochralski pulling *** crystal structure analysis was *** is found that the cNA crystal belongs to the tetragonal system with P-421m space *** cell parameters a=b=0.77461 nm and c=0.51089 *** density and Mohs hardness of cNA crystal are 4.08 g/cm^(3) and 5.45,*** specific heat of the crystal is 0.57-0.77 J/(g·K)in the temperature range of 30-300℃.X-ray photoelectron spectro scopy(XPS)shows that the crystal has stable atomic valence states and chemical *** vibration state of polyhedra groups in the crystal was measured by Raman spectra,and the piezoelectric response was analyzed based on the calculated results for the polyhedra polarization dipole *** relative dielectric permittivity of the cNA crystal at room temperature was determined to be 11.80 and the electrical resistivity was measured to be on the order of 5×10^(6)Ω·cm at 800℃.

关键词： Piezoelectric Melilite crystal growth High-temperature czochralski Rareearths

Multiple-event-triggered adaptive fuzzy output-feedback control for MIMO uncertain nonlinear systems

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Science china(Technological Sciences) 2025年第2期68卷 216-226页

作者： Shuai SUI yu YANg Shaocheng TONg c.L.Philip cHEN School of Science Liaoning University of TechnologyJinzhou 121001China School of computer Science and Engineering South China University of TechnologyGuangzhou 510006China

The article addresses the output-feedback control issue for a class of multi-input multi-output(MIMO)uncertain nonlinear systems with multiple event-triggered mechanisms(ETM).compared to previous event-triggering studies,this paper aims to trigger both the output and filtered *** nonlinear dynamics are approximated using fuzzy logic systems(FLSs).Then,a novel kind of state observer has been designed to deal with unmeasurable state problems using the triggered output *** sampled estimated state,the triggered output signal,and the filtered signal are utilized to propose an event-triggering mechanism that consists of sensor-to-observer(SO)and observer-to-controller(Oc).An event-triggered output feedback control approach is given inside backstepping control,whereby the filter may be employed to circumvent the issue of the virtual control function not being differentiable at the trigger *** is testified that,according to the Lyapunov stability analysis scheme,all closed-loop signals and the system output are ultimately uniformly constrained by our control ***,the simulation examples are performed to confirm the theoretical findings.

关键词： event-triggered control(ETc) dynamic surface control(DSc) output-feedback control fuzzy adaptive control

Upper Bounds on the Multicolor Ramsey Numbers r_(k)(c_(4))

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Acta Mathematicae Applicatae Sinica 2025年第1期41卷 286-294页

作者： Tian-yu LI Qi-zhong LIN center for Discrete Mathematics Fuzhou UniversityFuzhou 350108China

The multicolor Ramsey number r_(k)(c_(4))is the smallest integer N such that any k-edge coloring of KN contains a monochromatic c_(4).The current best upper bound of r_(k)(c_(4))was obtained by chung(1974)and independently by Irving(1974),i.e.,r_(k)(c_(4))≤k^(2)+k+1 for all k≥*** is no progress on the upper bound since *** this paper,we improve the upper bound of r_(k)(c_(4))by showing that r_(k)(c_(4))≤k^(2)+k-1 for even k≥*** improvement is based on the upper bound of the Turan number ex(n,c4),in which we mainly use the double counting method and many novel ideas from Firke,Kosek,Nash,and Williford[***,Ser.B 103(2013),327-336].

关键词： Multicolor Ramsey number Turan number 4-cycle

Revisit the gibbs-Thomson Equation Fitting of Poly(butylene succinate) Based on Oligomer Extended-chain crystals

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cHINESE JOURNAL OF POLYMER ScIENcE 2025年第2期43卷 392-398页

作者： Li, Na Tian, yu-Pei Wu, Tian-yu Zhou, Qiong Ye, Hai-Mu china Univ Petr Coll New Energy & Mat Beijing 102249 Peoples R China

The equilibrium melting point (Tm0) is a crucial thermodynamic parameter for characterizing the crystallization and melting behavior of semi-crystalline polymers. However, the direct measurement of Tm0 poses a significant challenge because of the difficulty in physically fabricating fully-extended chain crystals of high-molecular-weight polymers. Therefore, various extrapolation equations for Tm0 have been proposed that utilize the thermal properties of ordinary folded-chain lamellae. Among these, the gibbs-Thomson equation is one of the most commonly employed for modeling. Despite its widespread use, there are notable variations in the Tm0 values obtained by different research groups, even when based on similar samples. This raises questions about the validity and accuracy of using the gibbs-Thomson equation to linearly extrapolate Tm0. In this study, we prepared a series of oligomer extended-chain crystals (Eccs) of poly(butylene succinate) (PBS) and used their properties for gibbs-Thomson fitting. The results reveal a perfect linear relationship, with an extrapolated Tm0 value of 136.08 degrees c. The basal surface free energy of the oligomer Eccs was calculated as 0.084 J/m2, which is approximately twice that of folded-chain lamellae. This difference is attributed to the aggregation of highly mobile free tails on the crystal surface. The two structural features of oligomer Eccs-large thickness and fixed surface-better fulfill the conditions for applying the gibbs-Thomson equation, ensuring its validity and accuracy. Therefore, we believe that the gibbs-Thomson fit can produce reliable results when sufficient high-quality data are used.

关键词： Equilibrium melting point Extended-chain crystal gibbs-Thomson equation Inclusion complex

MXene Hybridized Polymer with Enhanced Electromagnetic Energy Harvest for Sensitized Microwave Actuation and Self‑Powered Motion Sensing

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Nano-Micro Letters 2025年第3期17卷 265-279页

作者： yu‑Ze Wang yu‑chang Wang Ting‑Ting Liu Quan‑Liang Zhao chen‑Sha Li Mao‑Sheng cao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081People’s Republic of China School of Materials Science and Engineering Peking UniversityBeijing 100871People’s Republic of China School of Mechanical and Material Engineering North China University of TechnologyBeijing 100144People’s Republic of China Key Laboratory of Functional Inorganic Material chemistry Ministry of Education of the People’s Republic of ChinaHeilongjiang UniversityHarbin 150080People’s Republic of China

Polymeric microwave actuators combining tissue-like softness with programmablemicrowave-responsive deformation hold great promise for mobile intelligentdevices and bionic soft robots. However, their application is challenged by restricted electromagneticsensitivity and intricate sensing coupling. In this study, a sensitized polymericmicrowave actuator is fabricated by hybridizing a liquid crystal polymer with Ti3c2Tx(MXene). compared to the initial counterpart, the hybrid polymer exhibits unique spacechargepolarization and interfacial polarization, resulting in significant improvements of230% in the dielectric loss factor and 830% in the apparent efficiency of electromagneticenergy harvest. The sensitized microwave actuation demonstrates as the shortenedresponse time of nearly 10 s, which is merely 13% of that for the initial shape memory polymer. Moreover, the ultra-low content of MXene (upto 0.15 wt%) benefits for maintaining the actuation potential of the hybrid polymer. An innovative self-powered sensing prototype that combinesdriving and piezoelectric polymers is developed, which generates real-time electric potential feedback (open-circuit potential of ~ 3 mV) duringactuation. The polarization-dominant energy conversion mechanism observed in the MXene-polymer hybrid structure furnishes a new approachfor developing efficient electromagnetic dissipative structures and shows potential for advancing polymeric electromagnetic intelligent devices.

关键词： Microwave absorption Electromagnetic response Energy harvest Self-sensing Soft actuator

Bluish-green emission of novel BaAl_(2)ge_(2)O_(8):Eu^(2+) phosphors under near-ultraviolet excitation

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Journal of Rare Earths 2025年第1期43卷 30-38,I0002页

作者： Sk.Khaja Hussain Jae Su yu Department of Electronic Engineering Institute for Wearable Convergence ElectronicsKyung Hee University1 Seocheon-dongGiheung-guYongin-sGyeonggi-do446-701Republic of Korea Nanosensor Research Institute Hanyang University55 Hanyangdaehak-roSangnok-guAnsanGyeonggi-do15588Republic of Korea

A new class of phosphor samples,denoted as Ba_(1-x)Al_(2)ge_(2)O_(8):xEu^(2+)(BAgO:xEu^(2+))was synthesized using a Pechini-type sol-gel technique and subsequent thermal reduction in cO *** morphology and structural characteristics of both the BAgO host lattice and the Eu^(2+)ions activated BAgO phosphors were investigated through field-emission scanning electron microscopy and X-ray diffractometry analyses,*** BAgO host lattice has micro-sized particles and the Rietveld refinement reveals the presence of a monoclinic crystal phase,characterized by the space group I2/c(No.15).Introducing Eu^(2+)ions into Ba^(2+)sites under cO condition reduces the particle size,switching from microscale to *** the near-ultraviolet spectrum(353 nm),the BAgO:xEu^(2+)phosphors exhibit a broadband bluish-green photoluminescence(PL)emission characterized by a peak band at 492 *** phenomenon is attributed to the 4f^(6)5d^(1)→4f^(7) electronic *** BAgO:0.02Eu^(2+)phosphor shows the strongest bluish-green PL emission,and a co mprehensive description of the concentration quenching mechanism between Eu^(2+)ions is ***,the thermal stability of the optimized BAgO:0.02Eu^(2+)phosphor was investigated,and its activation energy was ***,the synthesized bluish-green BAgO:0.02Eu^(2+)phosphor holds the promise of being a novel and potential candidate for utilization in white light-emitting diode applications.

关键词： Broadband bluish-green Ba1Al_(2)ge_(2)O_(8):Eu^(2+) Near-ultraviolet excitation cothermal reduction White light-emitting diodes Rare earths

construction of a 12-metal Zn(Ⅱ)-Nd(Ⅲ) nanocluster for ratiometric fluorescence detection of inflammatory marker neopterin

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Journal of Rare Earths 2025年第2期43卷 270-275页

作者： Huanyin yu Xiaoping Yang Xiaoli Lv Xianfeng Huang college of chemistry and Materials Engineering Wenzhou UniversityZhejiang Key Laboratory of Carbon MaterialsKey Lab of Biohealth Materials and Chemistry of Wenzhou

A 12-metal Zn（Ⅱ）-Nd（Ⅲ） cluster 1（sizes:1.8 nm×2.0 nm×2.0 nm） was synthesized from a long-chain type Schiff base *** displays ratiometric fluorescence response to neopterin（Neo） with high selectivity and sensitivity,which can be expressed by the equation I545nm/I1060nm=A·[Neo]2+B·[Neo]+c.1 is used to quantitatively test Neo concentrations in fetal calf serum（FcS） and urine,and the recovery ranges are 98.57%-103.82% and 99.25%-103.50%,respectively,while the relative standard deviations（RSDs） are 7.89%-9.46% and 1.85%-4.16%,*** limits of detection of 1 to Neo in FcS and urine are 0.034 and 0.021 μmol/L,respectively.

关键词： Neopterin NIR luminescence Rare earths Ratiometric fluorescence detection Zn(II)-Nd(III) nanocluster

correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： Peng Li Meifeng cai Shengjun Miao yuan Li yu Wang Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State Key Laboratory of coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in china were adopted,a newly defined characteristic parameter c_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with *** is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationship between the rock quality designation(RQD)and *** maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the c_(ERP)at the same *** addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of c_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and c_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification

coPSe nanoparticles confined in nitrogen-doped dual carbon network towards high-performance lithium/potassium ion batteries

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chinese chemical Letters 2025年第1期36卷 568-573页

作者： Zhong-Hui Sun yu-Qi Zhang Zhen-Yi gu Dong-Yang Qu Hong-yu guan Xing-Long Wu guangdong Engineering Technology Research center for Photoelectric Sensing Materials and Devices c/o School of Chemistry and Chemical EngineeringGuangzhou UniversityGuangzhou 510006China MOE Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal UniversityChangchun 130024China

The metal ion batteries have gained widespread attention for wearable electronics due to their competitive energy density and long cycling *** the advanced anode materials is significant for next generation energy storage ***,severe electrode volume changes and sluggish redox kinetics are the critical problems for lithium/potassium ion batteries(LIBs/PIBs)towards large-scale ***,we prepare a novel anode material,which consists of reduced graphene oxide wrapping one-dimensional(1D)N-doped porous carbon nanotube with cobalt phosphoselenide(coPSe)nanoparticles embedded inside them(r gO@co PSe/Nc).Benefited from the dual carbon decorations and ultrafine nanoparticles structure,it achieves a reversible capacity of 245 mAh/g at 5 A/g after 2000 cycles for LIBs and 215 mAh/g at 1 A/g after 500 cycles for *** pseudocapacitance and gITT measurements are used to investigate the electrochemical kinetics of r gO@co PSe/Nc for *** addition,the lithium ion full cell also shows good electrochemical performance when paired with high capacity LiNi_(0.8)co_(0.1)Mn_(0.1)O_(2) *** work provides a feasible electrode design strategy for high-efficiency metal ion batteries based on multidimensional nanoarchitecture engineering and composition tailoring.

关键词： cobalt phosphoselenide Lithium-ion batteries Potassium-ion batteries Reduced graphene oxide Structural stability Full cell

Vedolizumab serum trough concentrations with and without thiopurines in ulcerative colitis: The prospective VIEWS pharmacokinetics study

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World Journal of gastroenterology 2025年第2期31卷 102-112页

作者： Thanaboon chaemsupaphan Aviv Pudipeddi Hui-yu Lin Sudarshan Paramsothy Viraj c Kariyawasam Melissa Kermeen Rupert W Leong Department of gastroenterology and Liver Services Concord Repatriation General HospitalSydney 2139New South WalesAustralia Faculty of Medicine Siriraj HospitalMahidol UniversityBangkok 10700Thailand Faculty of Medicine and Health University of SydneySydney 2139New South WalesAustralia Department of gastroenterology Tan Tock Seng HospitalSingapore 308433Singapore Faculty of Medicine and Health Sciences Macquarie UniversitySydney 2139New South WalesAustralia Department of gastroenterology and Hepatology Blacktown HospitalSydney 2148New South WalesAustralia Blacktown clinical School Western Sydney UniversitySydney 2148New South WalesAustralia

BAcKgROUND Ulcerative colitis(Uc)is a chronic inflammatory condition requiring continuous treatment and *** is limited pharmacokinetic data on vedolizumab during maintenance therapy and the effect of thiopurines on vedolizumab trough concentrations is *** To investigate the exposure-response relationship of vedolizumab and the impact of thiopurine withdrawal in Uc patients who have achieved sustained clinical and endoscopic remission during maintenance *** This is a post-hoc analysis of prospective randomized clinical trial(VIEWS)involving Uc patients across 8 centers in Australia from 2018 to *** in clinical and endoscopic remission were randomized to continue or withdraw thiopurine while receiving *** evaluated vedolizumab serum trough concentrations,presence of anti-vedolizumab antibodies,and clinical outcomes over 48 weeks to assess exposure-response asso-ciation and impact of thiopurine *** There were 62 Uc participants with mean age of 43.4 years and 42%were *** participants received vedolizumab as maintenance therapy with 67.7%withdrew *** serum trough concentrations remained stable over 48 weeks regardless of thiopurine use,with no anti-vedolizumab antibodies ***-tients with clinical remission had higher trough concentrations at week *** quartile analysis,a threshold of>11.3μg/mL was associated with sustained clinical remission,showing a sensitivity of 82.4%,specificity of 60.0%,and an area of receiver operating characteristic of 0.71(95%cI:0.49-0.93).Patients discontinuing thiopurine required higher vedolizumab concentrations for achieving *** A positive exposure-response relationship between vedolizumab trough concentrations and Uc outcomes suggests that monitoring drug levels may be *** thiopurine did not influence vedolizumab levels,its with-drawal may necessitate higher vedolizumab trough concentrations to maintain remi

关键词： Pharmacokinetic Vedolizumab Thiopurine Ulcerative colitis Trough concentration Antibody Inflammatory bowel diseases