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Frontiers of Chemical Science and Engineering 2024年第5期18卷 95-103页

作者： Jianxia Gu Ying Zhu Haiyan Zheng Chunyi Sun Zhongmin Su department of Chemistry Xinzhou Normal UniversityXinzhou 034000China School of Chemistry Northeast Normal UniversityChangchun 130024China

A novel,cheap and highly efficient Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C nanocomposite has been successfully constructed through simple one-step carbonization method in a nitrogen *** in the precursor can effectively anchor molybdenum-based Keggin-type polyoxometallate and NiCo-layered double hydroxide through electrostatic and coordination interactions,which avoids the aggregation of catalyst particles during the pyrolysis *** optimization,the obtained Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C possesses small size(3-8 nm),large specific surface area and hierarchical pore *** importantly,Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C presents remarkable hydrogen evolution reaction activity with low overpotentials in 0.5 mol·L^(-1)H_(2)SO_(4)(102.3 mV)and 1 mol·L^(-1)KOH(95 mV)to afford the current density of 10 mA·cm^(-2),as well as small Tafel slopes of 82.49 and 99.92 mV·dec^(-1),***,this catalyst also shows outstanding stability for 12 h without a significant change in current *** excellent catalytic performance of Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C can put down to the synergistic effect between multiple components and the small size of the *** work provides unique insights into the preparation of efficient transition metal-based catalysts for HER.

关键词： polyoxometallates layered double hydroxide transition metal-based electrocatalysts hydrogen evolution reaction

Curvature-enhanced multipartite coherence in the multiverse

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Chinese Physics C 2024年第7期48卷 259-272页

作者：吴树民王春旭王锐迪李金璇黄晓理曾浩生 department of Physics Liaoning Normal UniversityDalian 116029China department of Physics Hunan Normal UniversityChangsha 410081China

Here,we study the quantum coherence of N-partite Greenberger-Horne-Zeilinger(GHZ)and W states in the multiverse consisting of N causally disconnected de Sitter ***,N-partite coherence increases monotonically with curvature,whereas the curvature effect destroys quantum entanglement and discord,indicating that the curvature effect is beneficial to quantum coherence and harmful to quantum correlations in the *** find that with an increase in n expanding de Sitter spaces,the N-partite coherence of the GHZ state increases monotonically for any curvature,whereas the quantum coherence of the W state decreases or increases monotonically depending on the *** find a distribution relationship,which indicates that the correlated coherence of the N-partite W state is equal to the sum of all bipartite correlated coherence in the *** coherence exhibits unique properties in the multiverse,suggesting that it may provide some evidence for the existence of the multiverse.

关键词： multiverse curvature effect multipartite coherence

A dual-mode optical thermometer based on dual-excitation Bi^(3+),Sm^(3+)co-doped Y_(4)GeO_(8) phosphors

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Journal of Rare Earths 2024年第8期42卷 1437-1446,I0002页

作者： Danyu Zhang Yuxuan Luo Junyu Chen Lianjie Li Hai Guo department of Physics Zhejiang Normal UniversityJinhua321004China

Dual-excitation and dual-emission Y_(4)GeO_(8):Bi^(3+),Sm^(3+)phosphors were manufactured by traditional solidphase sintering *** X-ray diffraction,morphology,photoluminescence,energy transfer process and temperature sensing properties of Y_(4)GeO_(8):Bi^(3+),Sm^(3+)samples were comprehensively *** Y4GeO_(8):Bi^(3+),Sm^(3+)phosphors exhibit characteristic emissions of Bi^(3+)(^(3)P_(1)→^(1)S_(0)) and Sm^(3+)(^(4)G_(5/2)→^(6)H)under both 290 and 347 nm *** fluorescence intensity ratio and Commission International de L'Eclairage coordinates modes,Y_(4)GeO_(8):Bi^(3+),Sm^(3+)samples present excellent temperature measurement *** maximum relative sensitivity(S_(r-max)) values of the former are 1.55%/K(460 K,290 nm excitation) and 0.82%/K(506 K,347 nm excitation).The S_(r-max)(x) values of the latter are 0.21 %/K(437 K,290 nm excitation) and 0.15%/K(513 K,347 nm excitation).These results illustrate that Y_(4)GeO_(8):Bi^(3+),Sm^(3+)phospho rs can be used as a candidate material for a dual-mode optical thermometer under dual-excitation.

关键词： Dual-mode optical thermometer Luminescent properties Y_(4)GeO_(8):Bi^(3+) Sm^(3+)phosphors Rare earths

Ultrahigh-brightness 50 MeV electron beam generation from laser wakefield acceleration in a weakly nonlinear regime

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Matter and Radiation at Extremes 2024年第3期9卷 4-10页

作者： Zhongtao Xiang Changhai Yu Zhiyong Qin Xuhui Jiao Jiahui Cheng Qiaoxuan Zhou Gatie Axi Jianghua Jie Ya Huang Jintan Cai Jiansheng Liu department of Physics Shanghai Normal UniversityShanghai 200234China

We propose an efficient scheme to produce ultrahigh-brightness tens of MeV electron beams by designing a density-tailored plasma to induce a wakefield in the weakly nonlinear regime with a moderate laser energy of 120 *** this scheme,the second bucket of the wakefield can have a much lower phase velocity at the steep plasma density down-ramp than the first bucket and can be exploited to implement longitudinal electron injection at a lower laser intensity,leading to the generation of bright electron beams with ultralow emittance together with low energy ***-dimensional particle-in-cell simulations are carried out and demonstrate that high-quality electron beams with a peak energy of 50 MeV,ultralow emittance of28 nm rad,energy spread of 1%,charge of 4.4 pC,and short duration less than 5 fs can be obtained within a 1-mm-long tailored plasma density,resulting in an ultrahigh six-dimensional brightness B6D,n of2×1017 A/m2/0.1%.By changing the density parameters,tunable bright electron beams with peak energies ranging from 5 to 70 MeV,a small emittance of B0.1 mm mrad,and a low energy spread at a few-percent level can be *** bright MeV-class electron beams have a variety of potential applications,for example,as ultrafast electron probes for diffraction and imaging,in laboratory astrophysics,in coherent radiation source generation,and as injectors for GeV particle accelerators.

关键词： weakly nonlinear acceleration

Tunable luminescence of Bi^(3+)/Eu^(3+)-doped SiO_(2)-Al_(2)O_(3)-MCO_(3)(M=Ca,Sr,Ba) glasses for WLED

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Journal of Rare Earths 2024年第9期42卷 1652-1657,I0001页

作者： Falin Zhang Xiaoying Liang Rongfei Wei Hai Guo Fangfang Hu department of Physics Zhejiang Normal UniversityJinhua321004China

In this work,a group of Bi^(3+)/Eu^(3+)-doped SiO2-Al_(2)O_(3)-MCO_(3)(M=Ca,Sr,Ba) glasses were fabricated through melt-quenching *** structure and photoluminescence characters were studied via Xray diffraction(XRD),UV-Vis transmission spectra(TRS),excitation spectra,emission spectra and decay *** XRD results show that no nano-crystal phase forms in glass matrix with different doping concentrations of Bi^(3+)and Eu^(3+)*** regulating optical alkalinity value,the intensity of Bi^(3+)ions increases and the peak position shifts to red *** Bi^(3+)/Eu^(3+) co-doped glasses show a blue-white-yellow-red luminescence by changing concentration of Eu^(3+) *** transfer efficiency from Bi^(3+) to Eu^(3+) can reach as high as 10.54%.At 423 K, the emission intensity of 55SiO_(2)-10Al_(2)O_(3)-35BaO-0.25Bi_(2)O_(3)(GBE0.5) is 31.1% of that at 308 ***,the activation energy of the glass matrix is 0.251 *** results suggest that these Bi^(3+)/Eu^(3+) co-doped glass samples possess potential application in LED field.

关键词： Bi^(3+) Eu^(3+) Glass White light-emitting diode Energy transfer Rare earths

Nondegenerate Soliton Solutions of(2+1)-Dimensional Multi-Component Maccari System

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Chinese Physics Letters 2024年第6期41卷 11-17页

作者：孟勇方乒乒林机 department of Physics Zhejiang Normal UniversityJinhua 321004China

For a multi-component Maccari system with two spatial dimensions,nondegenerate one-soliton and two-soliton solutions are obtained with the bilinear *** can be seen by drawing the spatial graphs of nondegenerate solitons that the real component of the system shows a cross-shaped structure,while the two solitons of the complex component show a multi-solitoff *** the same time,the asymptotic analysis of the interaction behavior of the two solitons is conducted,and it is found that under partially nondegenerate conditions,the real and complex components of the system experience elastic collision and inelastic collision,respectively.

关键词： structure. degenerate soliton

Rare earth fluorescent nanoprobes with minimal side effects enable tumor microenvironment activation for chemotherapy

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Journal of Rare Earths 2024年第2期42卷 256-262,I0001页

作者： Tianqi Cao Yuxin Liu Qi Jia Xiaolu Wang Shouqiang Zhang Jing Zhou department of Chemistry Capital Normal UniversityBeijing100048China

Chemotherapy,the use of antitumor drugs to kill cancer cells,is currently one of the most effective treatments for ***,serious toxic side effects caused by long-term drug accumulation can cause significant damage to the body,which limits the clinical application of antitumor *** this study,a novel RENPs@DOX-Fe nanoprobe(NP) was constructed by coating the surface of rare earth nanomaterials(NaLuF_(4):Yb,Er) with a complex formed by doxorubicin(DOX) and iron ion(Ⅲ).Due to the low toxicity of anthracycline-metal complexes,the damage to normal cells is *** unique acidic microenvironment in tumor cells facilitates the decomposition and gradual release of DOX from the DOX-Fe *** addition,the DOX-Fe complex can convert near-infrared(NIR) light into heat energy,which promotes the decomposition of the complex,further enhancing the release of DOX in the tumor *** change of ratio fluorescence of rare earth nanomaterials at 660 and 1550 nm after DOX release enables visual monitoring of drug release,which can potentially improve the chemotherapeutic *** vitro experiments established that RENPs@DOX-Fe NPs with NIR illumination had good therapeutic efficacy in *** work provides new insights into designing tumor microenvironment-responsive nanoprobes for chemotherapy with minimal side effects.

关键词： Rare earth nanoprobes Fluorescence Ratiometric imaging DOX Chemotherapy

Elevational patterns of warming effects on plant community and topsoil properties: focus on subalpine meadows ecosystem

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Journal of Mountain Science 2024年第1期21卷 146-159页

作者： HAO Aihua LUO Zhengming CHEN Xiaojiang department of Geography Xinzhou Normal UniversityXinzhou 034000China department of Biological Sciences Xinzhou Normal UniversityXinzhou 034000China

Climate warming profoundly affects plant biodiversity, community productivity, and soil properties in alpine and subalpine grassland ecosystems. However, these effects are poorly understood across elevational gradients in subalpine meadow ecosystems. To reveal the elevational patterns of warming effects on plant biodiversity, community structure, productivity, and soil properties, we conducted a warming experiment using open-top chambers from August 2019 to August 2022 at high(2764 m a. s. l.), medium(2631 m a. s. l.), and low(2544 m a. s. l.) elevational gradients on a subalpine meadow slope of Mount Wutai, Northern china. Our results showed that three years of warming significantly increased topsoil temperature but significantly decreased topsoil moisture at all elevations(P<0.05), and the percentage of increasing temperature and decreasing moisture both gradually raised with elevation lifting. Warming-induced decreasing proportions of soil organic carbon(SOC, by 19.24%), and total nitrogen(TN, by 24.56%) were the greatest at high elevational gradients. Experimental warming did not affect topsoil C: N, p H, NO_(3)^(-)-N, or NH_(4)^(+)-N at the three elevational gradients. Warming significantly increased species richness(P<0.01) and Shannon-Weiner index(P<0.05) at low elevational gradients but significantly decreased belowground biomass(P<0.05) at a depth of 0–10 cm at three elevational gradients. Warming caused significant increases in the aboveground biomass in the three elevational plots. Warming significantly increased the aboveground biomass of graminoids in medium(by 92.47%) and low(by 98.25%) elevational gradients, that of sedges in high(by 72.44%) and medium(by 57.16%) elevational plots, and that of forbs in high(by 75.88%), medium(by 34.38%), and low(by 74.95%) elevational plots. Species richness had significant linear correlations with SOC, TN, and C: N(P<0.05), but significant nonlinear responses to soil temperature and soil moisture in the warmed treatm

关键词： Warming effect Plant diversity pattern Community structure change Elevation gradient Alpine meadow ecosystem Mount Wutai

Probing the peripheral self-generated magnetic field distribution in laser-plasma magnetic reconnection with Martin-Puplett interferometer polarimeter

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Chinese Physics B 2024年第4期33卷 129-134页

作者：张雅芃姚嘉文刘正东马作霖仲佳勇 department of Astronomy Beijing Normal UniversityBeijing 100875China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China

Magnetic reconnection of the self-generated magnetic fields in laser-plasma interaction is an important laboratory method for modeling high-energy density astronomical and astrophysical *** use the Martin-Puplett interferometer(MPI)polarimeter to probe the peripheral magnetic fields generated in the common magnetic reconnection configuration,two separated coplanar plane targets,in laser-target *** introduce a new method that can obtain polarization information from the interference pattern instead of the sinusoidal function fitting of the intensity.A bidirectional magnetic field is observed from the side view,which is consistent with the magneto-hydro-dynamical(MHD)simulation results of self-generated magnetic field *** find that the cancellation of reverse magnetic fields after averaging and integration along the observing direction could reduce the magnetic field strength by one to two orders of *** indicates that imaging resolution can significantly affect the accuracy of measured magnetic field strength.

关键词： laser-plasma experiment polarimeter self-generated magnetic field magnetic reconnection

Detecting short-term gravitational waves from post-merger hyper-massive neutron stars with a kilohertz detector

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Chinese Physics B 2024年第8期33卷 222-228页

作者：陈奕康朱宗宏 Institute for Frontier in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China department of Astronomy Beijing Normal UniversityBeijing 100875China

Gravitational waves emanating from binary neutron star inspirals,alongside electromagnetic transients resulting from the aftermath of the GW170817 merger,have been successfully ***,the intricate post-merger dynamics that bridge these two sets of observables remain *** includes if,and when,the post-merger remnant star collapses to a black hole,and what are the necessary conditions to power a short gamma-ray burst,and other observed electromagnetic *** focus is on the detection of gravitational wave(GW)emissions from hyper-massive neutron stars(NSs)formed through binary neutron star(BNS)*** several kilohertz GW detectors,we simulate BNS mergers within the detection limits of LIGO-Virgo-KARGA *** objective is to ascertain the fraction of simulated sources that may emit detectable post-merger GW *** kilohertz detectors equipped with a new cavity design,we estimate that approximately 1.1%-32%of sources would emit a detectable post-merger GW *** fraction is contingent on the mass converted into gravitational wave energy,ranging from 0.01M_(sun)to 0.1M_(sun).Furthermore,by evaluating other well-regarded proposed kilohertz GW detectors,we anticipate that the fraction can increase to as much as 2.1%-61%under optimal performance conditions.

关键词： neutron star mergers gravitational waves