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ca.(2)MnO_(4)-layered perovskite modified by NaNO_(3)for chemica.-looping oxidative dehydrogenation of ethane to ethylene

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Chinese Journal of Chemica. Engineering 2024年第4期68卷 53-64页

作者： Weixiao Ding Kun Zhao Shica. Jiang zhen Huang Fang He College of Chemistry and Bioengineering Guilin University of TechnologyGuilin 541006China Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640China School of Chemistry and Chemica. Engineering Nanjing University of Science and TechnologyNanjing 210094China

Chemica.-looping oxidative dehydrogenation(CL-ODH)is a process designed for the conversion of alkanes into olefins through cyclic redox reactions,eliminating the need for gaseous O_(2).In this work,we investigated the use of ca.(2)MnO_(4)-layered perovskites modified with NaNO_(3) dopants,serving as redox ca.alysts(also known as oxygen ca.riers),for the CL-ODH of ethane within a temperature range of 700-780℃.Our findings revealed that the incorporation of NaNO_(3) as a modifier significa.tly-nhanced the selectivity for-thylene generation from ca.(2)MnO_(4).At 750℃and a gas hourly space velocity of 1300 h^(-1),we achieved an-thane conversion up to 68.17%,accompanied by a corresponding-thylene yield of 57.39%.X-ray photoelectron spectroscopy analysis unveiled that the doping NaNO_(3) onto ca.(2)MnO_(4) not only played a role in reducing the oxidation state of Mn ions but also increased the lattice oxygen content of the redox ***,formation of NaNO_(3) shell on the surface of ca.(2)MnO_(4) led to a reduction in the concentration of manganese sites and modulated the oxygen-releasing behavior in a step-wise *** modulation contributed significa.tly to the enhanced selectivity for ethylene of the NaNO_(3)-doped ca.(2)MnO_(4) *** findings provide compelling evidence for the potential of ca.(2)MnO_(4)-layered perovskites as promising redox ca.alysts in the context of CL-ODH reactions.

关键词： Chemica.-looping oxidative dehydrogenation Ethane Ethylene NaNO_(3)-doped ca.(2)MnO_(4)redox ca.alyst Layered perovskites

Stress relaxation properties of ca.cium silica.e hydrate:a molecular dynamics study

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第2期25卷 97-115页

作者： Zhicheng GENG Shengwen TANG Yang WANG Hubao A zhen HE Kai WU Lei WANG State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan430072China Key Laboratory of Advanced Civil Engineering Materials of Ministry of Educa.ion School of Materials Science and EngineeringTongji UniversityShanghai200092China College of Materials Science and Engineering Xi’an University of Architecture and TechnologyXi’an710055China

The time-dependent viscoelastic response of cement-based materials to applied deformation is far from fully understood at the atomic *** silica.e hydrate(C-S-H),the main hydration product of Portland cement,is responsible for the viscoelastic mechanism of cement-based *** this study,a molecular model of C-S-H was developed to explain the stress relaxation characteristics of C-S-H at different initial deformation states,ca.Si ratios,temperatures,and water contents,which ca.not be accessed *** stress relaxation of C-S-H occurs regardless of whether it is subjected to initial shear,tensile,or compressive deformation,and shows a heterogeneous *** plays a crucial role in the stress relaxation process.A large ca.Si ratio and high temperature reduce the cohesion between the ca.cium-silica.e layer and the interlayer region,and the viscosity of the interlayer region,thereby accelerating the stress relaxation of *** effect of the hydrogen bond network and the morphology of C-S-H on the evolution of the stress relaxation characteristics of C-S-H at different water contents was elucidated by nonaffine mean squared *** results shed light on the stress relaxation characteristics of C-S-H from a microscopic perspective,bridging the gap between the microscopic phenomena and the underlying atomic-level mechanisms.

关键词： ca.cium silica.e hydrate(C-S-H) Stress relaxation ca.Si ratio Temperature Water content Atomic simulation

Enhanced red luminescence of ca.(3)Si_(2−x)M_(x)O_(7):Eu^(3+)(M=Al,P)phosphors via partial substitution of Si^(4+) for applica.ions in white light-emitting diodes

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Rare Metals 2024年第2期43卷 736-748页

作者： Yu-Hao Ma Xi Gao Wen-Tao Zhang zhen-Rui Yang Zhou Zhao Chen Qu College of Materials and Chemistry and Chemica. Engineering Chengdu University of TechnologyChengdu610059China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu610059China International Advanced Energy Science Research and Educa.ion Center Graduate School of Energy ScienceKyoto UniversityYoshida-HonmachiKyoto606-8501Japan

A red-emitting phosphor ca.(2.91)Si_(2)O_(7):0.09Eu^(3+) with partial Al^(3+)/P^(5+) substitution on Si^(4+) was synthesized via a simple solid-state method,and the effects of the introduction of the M^(3+/5+)(M=Al,P)ions on the crystal structure and photoluminescence performance of ca.(2.91)Si_(2−x)M_(x)O_(7):0.09Eu^(3+) phosphors were *** X-ray diffraction(XRD),energy-dispersive X-ray spectroscopy(EDS),and X-ray photoelectron spectroscopy(XPS)results revealed that the structure of ca.(3)Si_(2)O_(7) remained the same after the introduction of Al^(3+) and P^(5+) *** characteristic emission of Eu^(3+)-doped ca.(3)Si_(2−x)M_(x)O_(7) phosphors exhibited two main peaks at 617 nm(red)and 593 nm(orange)under excitation at 394 nm,which originated from the^(5)D_(0)→^(7)F_(2)and^(5)D_(0)→^(7)F_(1) electron transitions of Eu^(3+) *** the partial substitution of Al^(3+) and P^(5+),the red emission intensities of the ca.(2.91)Si_(2)O_(7):0.09Eu^(3+) phosphors were significa.tly enhanced by 1.88-and 1.42-fold,respectively,which is attributed to the crystal-field effect around Eu^(3+).Meanwhile,the luminescence intensities of the ca.(2.91)Si_(1.96)Al_(0.04)O_(7):0.09Eu^(3+) and ca.(2.91)Si_(1.94)P_(0.06)O_(7):0.09Eu^(3+) phosphors at 210℃ were 79.36%and 77.53%of those at 30°C,respectively,indica.ing their excellent thermal ***,the as-prepared ca.(2.91)Si_(1.96)Al_(0.04)O_(7):0.09Eu^(3+)and ca.(2.91)Si_(1.94)P_(0.06)O_(7):0.09Eu^(3+) red-emitting phosphors were combined with a near-ultraviolet chip of 395 nm to fabrica.e red-light-emitting diode(LED)and white(w)-LED devices with excellent chromaticity *** summary,Al^(3+)/P^(5+)-substituted ca.(2.91)Si_(2)O_(7):0.09Eu^(3+) ca. serve as red-emitting phosphors for applica.ions in w-LEDs.

关键词： ca.(3)Si_(2)O_(7) Red-emitting phosphor Structure substitution Luminescence enhancement Crystal-field effect White light-emitting diode

Revealing excited states of rotational Bose-Einstein condensates

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The Innovation 2024年第1期5卷 41-48页

作者： Jianyuan Yin zhen Huang Yongyong ca. Qiang Du Lei Zhang School of Mathematica. Sciences Laboratory of Mathematics and Applied MathematicsPeking UniversityBeijing 100871China Department of Mathematics National University of SingaporeSingapore 119076Singapore Department of Mathematics University of CaliforniaBerkeleyBerkeleyCA 94720USA School of Mathematica. Sciences Beijing Normal UniversityBeijing 100875China Department of Applied Physics and Applied Mathematics and Data Science Institute Columbia UniversityNew YorkNY 10027USA Beijing International Center for Mathematica. Research Center for Quantitative BiologyCenter for Machine Learning ResearchPeking UniversityBeijing 100871China

Rotational Bose-Einstein condensates ca. exhibit quantized vortices as topologica. *** this study,the ground and excited states of the rotational Bose-Einstein condensates are systematica.ly studied by ca.culating the stationary points of the Gross-Pitaevskii energy *** excited states and their connections at different rotational frequencies are revealed in solution landsca.es constructed with the constrained high-index saddle dynamics *** excitation mechanisms are identified:vortex addition,rearrangement,merging,and *** demonstrate changes in the ground state with increasing rotational frequencies and decipher the evolution of the stability of ground states.

关键词： method rotational excited

The combined detection of ca.cinoembryonic antigen,ca.cinogenic antigen 125,and ca.cinogenic antigen 19-9 in colorectal ca.cer patients

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2073-2079页

作者： Ling-zhen Gong Qian-Wen Wang Jie-Wen Zhu Department of Clinica. Laboratory Huangshi Central Hospital(Affiliated Hospital of Hubei Polytechnic University)Hubei Key Laboratory of Kidney Disease Pathogenesis and InterventionHuangshi Tumor Molecular Diagnosis and Treatment Key LaboratoryHuangshi 435000Hubei ProvinceChina

BACKGROUND Hepatic metastases are common and difficult to treat after colorectal ca.cer(CRC)*** predictive value of ca.cinoembryonic antigen(CEA),ca.cer antigen(ca.125 and ca.9-9 combined tests for liver metastasis is *** To evaluate predictive value of combined tests for CEA,ca.25,and ca.9-9 levels in patients with liver metastases of *** The retrospective study included patients with CRC alone(50 ca.es)and patients with CRC combined with liver metastases(50 ca.es)who were hospitalized between January 2021 and January *** CEA,ca.25 and ca.9-9 levels were compared between the two groups,and binary logistic regression was used to analyze the predictive value of the combination of these tumor markers in liver *** addition,we performed receiver operating characteristic(ROC)curve analysis to assess its diagnostic *** The results showed that the serum CEA,ca.25 and ca.9-9 levels in the CRC with liver metastasis group were significa.tly higher than those in the CRC alone ***,the average serum CEA level in the CRC with liver metastasis group was 162.03±810.01 ng/mL,while that in the CRC alone group was 5.71±9.76 ng/mL;the average serum ca.25 levels were 43.47±83.52 U/mL *** 13.5±19.68 U/mL;the average serum ca.9-9 levels were 184.46±473.13 U/mL and 26.55±43.96 U/mL *** addition,binary logistic regression analysis showed that ca.25 was significa.t in predicting CRC liver metastasis(Pca.25 and ca.9-9 were 0.607,0.692 and *** These results suggest that combined detection of these tumor markers may help early detection and intervention of CRC liver metastasis,thereby improving patient prognosis.

关键词： Colorectal ca.cer Liver metastasis Serum markers ca.cinoembryonic antigen ca.cer antigen 125 ca.cer antigen 19-9 Receiver operating characteristic analysis

Bacteria-responsive programmed self-activating antibacterial hydrogel to remodel regeneration microenvironment for infected wound healing

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National Science Review 2024年第4期11卷 254-270页

作者： Yutong Yang Jiaxin Wang Shengfei Huang Meng Li Jueying Chen Dandan Pei zhen Tang Baolin Guo State Key Laboratory for Mechanica. Behavior of Materials and Frontier Institute of Science and Technology and Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine ResearchCollege of Stomatology Xi'an Jiaotong University Department of Orthopedics Tangdu Hospital Fourth Military Medical University Department of Orthopedics The First Affiliated Hospital of Xi'an Jiaotong University

There is still an urgent need to develop hydrogels with intelligent antibacterial ability to achieve on-demand treatment of infected wounds and accelerate wound healing by improving the regeneration microenvironment. We proposed a strategy of hydrogel wound dressing with bacteria-responsive self-activating antibacterial property and multiple nanozyme activities to remodel the regeneration microenvironment in order to significa.tly promote infected wound healing. Specifica.ly, p H-responsive H2O2self-supplying composite nanozyme（MSCO） and p H/enzyme-sensitive bacteria-responsive triblock micelles enca.sulated with lactate oxidase（PPEL） were prepared and enca.sulated in hydrogels composed of L-arginine-modified chitosan（ca. and phenylboronic acid-modified oxidized dextran（ODP） to form a ca.ca.e bacteria-responsive self-activating antibacterial composite hydrogel platform. The hydrogels respond to multifactorial changes of the bacterial metabolic microenvironment to achieve on-demand antibacterial and biofilm eradica.ion through transformation of bacterial metabolites, and chemodynamic therapy enhanced by nanozyme activity in conjunction with self-driven nitric oxide（NO） release. The composite hydrogel showed 'self-diagnostic' treatment for changes in the wound *** self-activating antibacterial therapy in the infection stage to self-adaptive oxidative stress relief and angiogenesis in the post-infection stage, it promotes wound closure, accelerates wound collagen deposition and angiogenesis, and completely improves the microenvironment of infected wound regeneration, which provides a new method for the design of intelligent wound dressings.

关键词： bacterial response hydrogel dressing multiple nanozyme activity biofilm elimination infected motion wound healing

Theoretica. and experimental investigations on an X-shaped vibration isolator with active controlled variable stiffness

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1371-1386页

作者： Zeyu CHAI J.T.HAN Xuyuan SONG Jian ZANG Yewei ZHANG zhen ZHANG College of Aerospace Engineering Shenyang Aerospace UniversityShenyang 110136China Jacobs School of Engineering University of California San DiegoSan Diego CA 92122U.S.A. Key Laboratory of Vibration and Control of Aero-Propulsion System Ministry of EducationNortheastern UniversityShenyang 110819China

A novel X-shaped variable stiffness vibration isolator(X-VSVI)is *** Runge-Kutta method,harmonic balance method,and wavelet transform spectra are introduced to evaluate the performance of the X-VSVI under various *** layer number,the installation angle of the X-shaped structure,the stiffness,and the active control parameters are systematica.ly *** addition,a prototype of the X-VSVI is manufactured,and vibration tests are ca.ried *** results show that the proposed X-VSVI has a superior adaptability to that of a traditional X-shaped mechanism,and shows excellent vibration isolation performance in response to different amplitudes and forms of ***,the vibration isolation efficiency of the device ca. be improved by appropriate adjustment of parameters.

关键词： bionic vibration isolation X-shaped structure variable stiffness structure nonlinear dynamics prototype experiment

Mn single-atoms decorated CNT electrodes for high-performance superca.acitors

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Nano Research 2024年第5期17卷 4039-4046页

作者： Qian Rong Chao Yuwen Yingkai Liu Yuanrong Liu Chunyang Wang Yang Wang Ding Zhang zhen Wen Yunnan Key Laboratory of Opto-Electronic Information Technology Institute of Physics and Electronic InformationYunnan Normal UniversityKunming 650500China Faculty of Metallurgica. and Energy Engineering Kunming University of Science and TechnologyKunming 650093China Department of Physics and Astronomy University of CaliforniaIrvineCA 92697USA School of Materials Science and Engineering National Institute for Advanced MaterialsSmart Sensing Interdisciplinary Science CenterNankai UniversityTianjin 300350China Jiangsu Key Laboratory for ca.bon-Based Functional Materials and Devices Institute of Functional Nano and Soft Materials(FUNSOM)Soochow UniversitySuzhou 215123China

Developing highly robust and efficient electrode materials is of critica. importance to promoting the energy density of current superca.acitors for ***,we report an efficient ca.alyst with monodispersed Mn single-atoms embedded in ca.bon nanotubes(Mn-CNTs)for enhancing the electrode performance of superca.acitors.A high specific ca.acitance(1523.6 F·g^(-1) at 1.0 A·g^(-1))ca. be achieved,which is about twice as high as the specific ca.acitance of the electrode material without the introduction of Mn ***,the asymmetric electrochemica. ca.acitor created with Mn-CNT and activated ca.bon exhibits a high energy density of 180.8 Wh·kg^(-1) at a power density of 1.4 kW·kg^(-1),much higher than most reported *** study shows that the integration of Mn atoms into the CNT ca. enhance the charge transport ca.acity and the number of polar active sites of Mn-CNT and then facilitate chemica. interactions between Mn-CNT and OH-.This work provides a novel strategy to enable high-energy storage in superca.acitors by introducing single-atoms into ca.bon nanotubes to improve electrodes’energy density and cycle life.

关键词： ca.bon nanotube(CNT) superca.acitor single-atoms power density energy density

An Updated Lagrangian Particle Hydrodynamics (ULPH)-NOSBPD Coupling Approach forModeling Fluid-Structure Interaction Problem

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 491-523页

作者： zhen Wang Junsong Xiong Shaofan Li Xin Lai Xiang Liu Lisheng Liu Hubei Key Laboratory of Theory and Applica.ion of Advanced Materials Mechanics Wuhan University of TechnologyWuhan430070China Department of Civil and Environmental Engineering The University of CaliforniaBerkeleyCA 94720USA Department of Engineering Structure and Mechanics Wuhan University of TechnologyWuhan430070China

A fluid-structure interaction approach is proposed in this paper based onNon-Ordinary State-Based Peridynamics(NOSB-PD)and Updated Lagrangian Particle Hydrodynamics(ULPH)to simulate the fluid-structure interaction problem with large geometric deformation and material failure and solve the fluid-structure interaction problem of Newtonian *** the coupled framework,the NOSB-PD theory describes the deformation and fracture of the solid material *** is applied to describe the flow of Newtonian fluids due to its advantages in computational *** framework utilizes the advantages of NOSB-PD theory for solving discontinuous problems and ULPH theory for solving fluid problems,with good computational stability and robustness.A fluidstructure coupling algorithm using pressure as the transmission medium is established to deal with the fluidstructure *** dynamic model of solid structure and the PD-ULPH fluid-structure interaction model involving large deformation are verified by numerica. *** results agree with the analytica. solution,the available experimental data,and other numerica. ***,the accuracy and effectiveness of the proposed method in solving the fluid-structure interaction problem are *** fluid-structure interactionmodel based on ULPH and NOSB-PD established in this paper provides a new idea for the numerica. solution of fluidstructure interaction and a promising approach for engineering design and experimental prediction.

关键词： Fluid-structure interaction(FSI) updated lagrangian particle hydrodynamics peridynamics meshfree method