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Journal of Rare Earths 2024年第8期42卷 1555-1559,I0005页

作者： hao Sun Lu Tian Xinqiang Gao Zhaojun Mo Jun shen baogen shen School of Rare Earths University of Science and Technology of ChinaHefei230026China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341000China Department of Energy and Power Engineering School of Mechanical EngineeringBeijing Institute of TechnologyBeijing100081China

The magnetic properties,magnetic phase transition and magnetocaloric effects(MCE) of Er_(3)Si_(2)C_(2) compound were investigated based on theoretical calculations and experimental *** on the first principles calculations,the antiferromagnetic(AFM) ground state type in Er_(3)Si_(2)C_(2) compound was predicted and its electronic structure was *** experimental results show that Ei_(3)Si_(2)C_(2) compound is an AFM compound with the Neel temperature(T_(N) of 7 K and undergoes a field-induced firstorder magnetic phase transition from AFM to ferromagnetic(FM) under magnetic fields exceeding 0.6 T at 2 *** magnetic transition process of Er_(3)Si_(2)C_(2) compound was investigated and *** values of the maximum magnetic entropy change(-ΔS_(M)^(max)) and the refrigeration capacity(RC) are 17 J/(kg·K)and 193 J/kg under changing magnetic fields of 0-5 T,*** a potential cryogenic magnetic refrigerant,the Er_(3)Si_(2)C_(2) compound also provides an interesting research medium to study the magnetic phase transition process.

关键词： Magnetic materials Magnetocaloric Metamagnetic transitions Magnetic phase transition Rare earths

h_(∞)/Passive Synchronization of Semi-Markov Jump Neural Networks Subject to hybrid Attacks via an Activation Function Division Approach

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Journal of Systems Science & Complexity 2024年第3期37卷 1023-1036页

作者： ZhANG Ziwei shen hao SU Lei School of Electrical and Information Engineering Anhui University of TechnologyMa'anshan 243002China Anhui Province Key Laboratory of Special heavy Load Robot and School of Electrical and Information Engineering Anhui University of TechnologyMa'anshan243002China

In this work,an h_(∞)/passive-based secure synchronization control problem is investigated for continuous-time semi-Markov neural networks subject to hybrid attacks,in which hybrid attacks are the combinations of denial-of-service attacks and deception attacks,and they are described by two groups of independent bernoulli *** this foundation,via the Lyapunov stability theory and linear matrix inequality technology,the h_(∞)/passive-based performance criteria for semi-Markov jump neural networks are ***,an activation function division approach for neural networks is adopted to further reduce the conservatism of the ***,a simulation example is provided to verify the validity and feasibility of the proposed method.

关键词： Activation function division approach deception attacks denial-of-service attacks h_(∞)/passive synchronization semi-Markov jump neural networks

Study of primordial deuterium abundance in big bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-Lin shen Jian-Jun he Key Laboratory of beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

big bang nucleosynthesis(bbN)theory predicts the primordial abundances of the light elements^(2) h(referred to as deuterium,or D for short),^(3)he,^(4)he,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by bbN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/h)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important bbN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)he,d(d,p)t,d(p,γ)^(3)he,and p(n,γ)d had the largest influence on the calculated D/h ***,the calculated D/h uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) he *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in bbN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： big bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

Investigation of Ce/bEA as a passive NO_(x)adsorber:*** aging deactivation mechanism

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Journal of Rare Earths 2024年第8期42卷 1524-1530,I0004页

作者： Yiying Ding Minghui Yu Xiaojie Yu Meiqing shen Jianqiang Wang Jun Wang Gurong shen School of Chemical Engineering and Technology Tianjin UniversityTianjin300350China School of Materials Science and Engineering Tianjin UniversityTianjin300350China National Rare Earth Catalysis Research Institute Dongying257000China

Ce/bEA has the potential to be applied as a novel passive NO_(x)absorber(PNA)in the after-treatment of vehicles due to its considerable NO_(x)storage ***,as a vehicle exhaust after-treatment material,it must withstand the test of long-term hydrothermal *** work examined the deactivation mechanism of Ce/bEA during hydrothermal aging.3.0 wt%Ce/bEA was prepared using the ionexchange method,and then subjected to hydrothermal treatment at 650℃with 10%h_(2)O for 1-12 h to obtain samples with different aging *** comparison,the h-bEA support was aged under the same ***-Emmett-Teller(bET)method,X-ray diffraction(XRD),Nh_(3)temperature programmed reduction(Nh_(3)-TPD),^(27)Al MAS nuclear magnetic resonance(^(27)Al MAS NMR),h_(2)temperature programmed reduction(h_(2)-TPR),and high resolution-transmission electron microscopy(hR-TEM)were performed to characterize the changes in PNA performance,structure,Ce species,and *** hR-TEM and h_(2)-TPR results show that CeO_(x)particles appear after hydrothermal aging,which results from the detachment and aggregation of active Ce *** on the^(27)Al MAS NMR results,we conclude that bEA zeolite dealumination leads to the loss of acidic sites and the transformation of active Ce species on the acidic sites into the less active CeO_(x).This is the primary reason for the hydrothermal aging deactivation of Ce/bEA.

关键词： Passive NO_(x)adsorber Ce/bEA hydrothermal aging CeO_(x) Dealumination Rare earths

Insight into the nitrogen-vacancy center formation in type-Ib diamond by irradiation and annealing approach

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Materials Futures 2024年第4期3卷 181-191页

作者： Taiqiao Liu Fanglin Lyu Tian Shao Diwei Zou Wei shen Yuzheng Guo Yuan Zhong Chaoyang Chen Liangchen Yi Zhaofu Zhang Andy h shen The Institute of Technological Sciences Wuhan UniversityWuhan 430072People’s Republic of China Gemmological Institute China University of GeosciencesWuhan 430074People’s Republic of China School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072People’s Republic of China Zhongnan Diamond Company Nanyang 473264People’s Republic of China hubei Key Laboratory of Electronic Manufacturing and Packaging Integration Wuhan UniversityWuhan 430072People’s Republic of China

Comprehending the microscopic formation of nitrogen vacancy(NV)centers in nitrogen-doped diamonds is crucial for enhancing the controllable preparation of NV centers and quantum *** followed by annealing simulations for a type-Ib diamond with a 900 ppm concentration of isolated nitrogen is conducted along different orientations and at different annealing *** these simulations,molecular dynamics(MD)with smoothly connected potential functions are *** simulations revealed the dynamic formation process of the NV center,which was subsequently verified by first-principles calculations and *** results indicate that vacancies undergo one or multiple migrations by exchanging sites with neighboring *** are three mechanisms for the formation of NV centers:direct irradiation-induced NV formation,irradiation with further annealing to form NV and vacancy migration(VM)during the annealing ***,the results show that both VM and NV center formations are affected by *** study clarifies the formation of NV centers across multiple scales and provides a solid foundation for the targeted preparation of NV centers.

关键词： diamond NV center irradiation annealing molecular dynamics

Investigation of Ce/bEA as a passive NO_(x)adsorber:*** occurrences of cerium and adsorption behavior

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Journal of Rare Earths 2024年第7期42卷 1265-1271,I0003页

作者： Minghui Yu Yiying Ding Xiaojie Yu Siwei Yan Meiqing shen Jianqiang Wang Jun Wang Gurong shen School of Materials Science and Engineering Tianjin UniversityTianjin300350China School of Chemical Engineering and Technology Tianjin UniversityTianjin300350China National Rare Earth Catalysis Research Institute Dongying257000China

Ce/bEA has great potential as a passive NO_(x)absorber(PNA)to reduce the NO_(x)emissions during the cold start phase especially in diesel engine for its high resistance to CO and suitable NO_(x)desorption temperature ***,as a novel material,its physical and chemical properties still remain *** this work,Ce/bEA was synthesized by ion-exchange method to identify the active species in NO_(x)adsorption,compared with aggregated Ce species in Ce/SiAlO_(x) prepared by impregnation method.X-ray diffraction(XRD),high resolution-transmission electron microscopy(hR-TEM)and aberration-corrected-scanning transmission electron microscopy(AC-STEM)were performed to confirm the isolated single atom formation of Ce species in Ce/***-vis diffraction reflection spectra(DRS)and X-ray photoelectron spectroscopy(XPS)were conducted to find the difference of chemical environment between the isolated Ce species and aggregated *** performance evaluation and temperature programmed reduction of hydrogen(h_(2)-TPR)results show the high NO_(x)storage capacity and active oxygen species quantity in Ce/*** is also found that the main NO_(x)adsorption species are Ce^(4+)-O^(∗)rather than Ce^(3+).NO_(x)-diffuse reflectance infrared Fourier transform spectroscopy(NO_(x)-DRIFTS)confirms that the bidentate nitrite species are the critical NO_(x)adsorption intermediates and the conception of NO_(x)adsorption and desorption processes is proposed.

关键词： Passive NO_(x)absorber Ce/bEA Isolated Ce species Rare earths

Function and dysfunction of GEMIN5:understanding a novel neurodevelopmental disorder

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Neural Regeneration Research 2024年第11期19卷 2377-2386页

作者： Charles h.Nelson Udai b.Pandey Department of Pediatrics Division of Child NeurologyChildren’s Hospital of PittsburghUniversity of Pittsburgh Medical CenterPittsburghPAUSA Children’s Neuroscience Institute Children’s Hospital of PittsburghUniversity of Pittsburgh Medical CenterPittsburghPAUSA

The recent identification of a neurodevelopmental disorder with cerebellar atrophy and motor dysfunction(NEDCAM)has resulted in an increased interest in GEMIN5,a multifunction RNA-binding *** the largest member of the survival motor neuron complex,GEMIN5 plays a key role in the biogenesis of small nuclear ribonucleoproteins while also exhibiting translational regulatory functions as an independent *** many questions remain regarding both the pathogenesis and pathophysiology of this new disorder,considerable progress has been made in the brief time since its *** this review,we examine GEMIN5 within the context of NEDCAM,focusing on the structure,function,and expression of the protein specifically in regard to the disorder ***,we explore the current animal models of NEDCAM,as well as potential molecular pathways for treatment and future directions of *** review provides a comprehensive overview of recent advances in our understanding of this unique member of the survival motor neuron complex.

关键词： cerebellar atrophy GEMIN5 neurodevelopmental disorder neurological disease SMN complex

A Probing Model of Secret Key Generation based on Channel Autocorrelation Function

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China Communications 2024年第6期21卷 163-175页

作者： Xia Enjun hu binjie shen Qiaoqiao School of Electronic and Information Engineering South China University of TechnologyGuangzhou 510641China

Secret key generation(SKG)is a promising solution to the problem of wireless communications *** the first step of SKG,channel probing affects it *** there have been some probing schemes,there is a lack of research on the optimization of the probing *** study investigates how to optimize correlated parameters to maximize the SKG rate(SKGR)in the time-division duplex(TDD)***,we build a probing model which includes the effects of transmitting power,the probing period,and the dimension of sample *** on the model,the analytical expression of the SKGR is ***,we formulate an optimization problem for maximizing the SKGR and give an algorithm to solve *** conclude the SKGR monotonically increases as the transmitting power *** mathematical proofs are given in this *** the simulation results,increasing appropriately the probing period and the dimension of the sample vector could increase the SKGR dramatically compared to a yardstick,which indicates the importance of optimizing the parameters related to the channel probing phase.

关键词： channel autocorrelation function channel probing optimization problem physical layer security secret key generation

Impact of high Sodium Diet on Neovascularization and Osseointegration around Titanium Implant:An in Vivo and in Vitro Study

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biomedical and Environmental Sciences 2024年第7期37卷 739-753页

作者： Keyuan Xu Xiaoting Tang Yun Xiang Yiding shen Zhennan Deng Pingping Ma Xinkun shen Department of Orthopaedics The Third Affiliated Hospital of Wenzhou Medical University(Ruian People’s Hospital)Wenzhou 325016ZhejiangChina School and hospital of Stomatology Wenzhou Medical UniversityWenzhou 325027ZhejiangChina

Objective A high sodium(hS)diet is believed to affect bone metabolism *** its impact on osseointegration of titanium(Ti)implants holds significant implications for postoperative dietary management of implanted *** This investigation probed the impact of sodium ions(Na^(+))on neovascularization and osteogenesis around Ti implants in vivo,utilizing micro-computed tomography,hematoxylin and eosin staining,and immunohistochemical ***,in vitro experiments assessed the effects of varied Na^(+)concentrations and exposure durations on human umbilical vein endothelial cells(hUVECs)and MC3T3-E1 *** In vivo,increased dietary sodium(0.8%-6.0%)led to a substantial decline in CD34 positive hUVECs and new bone formation around Ti implants,alongside an increase in inflammatory *** vitro,an increase in Na^(+)concentration(140-150 mmol/L)adversely affected the proliferation,angiogenesis,and migration of hUVECs,especially with prolonged *** MC3T3-E1 cells initially exhibited less susceptibility to high Na^(+)concentrations compared to hUVECs during short-term exposure,prolonged exposure to a hS environment progressively diminished their proliferation,differentiation,and osteogenic *** These findings suggest that hS diet had a negative effect on the early osseointegration of Ti implants by interfering with the process of postoperative vascularized bone regeneration.

关键词： high-sodium Implants Vascularization Osseointegration