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Cooperation between single atom catalyst and support to promote nitrogen electroreduction to ammonia:A theoretical insight

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Journal of Energy Chemistry 2024年第9期96卷 336-344页

作者： Wanying Guo Siyao Wang Hongxia Wang Qinghai Cai Jingxiang Zhao College of Chemistry and Chemical Engineering Harbin Normal UniversityHarbin 150025HeilongjiangChina

The co-catalysis between single atom catalyst(SAC)and its support has recently emerged as a promising strategy to synergistically boost the catalytic activity of some complex electrochemical reactions,encompassing multiple intermediates and ***,we utilized defective BC_(3)monolayer-supported SACs as a prototype to investigate the cooperative effects of SACs and their support on the catalytic performance of the nitrogen reduction reaction(NRR)for ammonia(NH_(3))*** results showed that these SACs can be firmly stabilized on these defective BC_(3)supports with high stability against ***,co-activation of the inert N_(2)reactant was observed in certain embedded SACs and their neighboring B atoms on certain BC3 sheets due to the noticeable charge transfer and significant N–N bond *** high-throughput screening revealed that the Mo/DV_(CC)and W/DV_(CC)exhibit superior NRR catalytic performance,characterized by a low limiting potential of−0.33 and−0.43 V,respectively,which can be further increased under acid conditions based on the constant potential ***,varying NRR catalytic activities can be attributed to the differences in the valence state of active ***,further microkinetic modeling analysis displayed that the turnover frequency of N_(2)–to–NH_(3)conversion on Mo/DV_(CC)is as large as 1.20×10^(−3)s^(−1)site^(−1) at 700 K and 100 bar,thus guaranteeing its ultra-fast reaction *** results not only suggest promising advanced electrocatalysts for NRR but also offer an effective avenue to regulate the electrocatalytic performance via the co-catalytic metal–support interactions.

关键词： Co-catalysis Single atom catalyst Nitrogen reduction DFT computations

Multi-hop routing for energy-efficiency enhancement in relay-assisted device-to-device communication

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The Journal of china Universities of Posts and Telecommunications 2015年第2期22卷 1-6,51页

作者： Zhao Jingyi Li Xi Xu Quansheng Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications

Financial and environment considerations present new trends in wireless network known as green communication. As one of the most promising network architectures, the device-to-device （D2D） communication should take seriously account to the energy-efficiency. Most of the existing work in the area of D2D communication only focus on the direct communication, however, the direct link D2D communication has to be limited in practice because of long distance, poor propagation medium and cellular interference, etc. A new energy-efficient multi-hop routing algorithm was investigated for multi-hop D2D system by jointly optimizing channel reusing and power allocation. Firstly, the energy-efficient multi-hop routing problem was formulated as a combinatorial optimization problem. Secondly, to obtain a desirable solution with reasonable computation cost, a heuristic multi-hop routing algorithm was presented to solve the formulated problem and to achieve a satisfactory energy-efficiency performance. Simulation shows the effectiveness of the proposed routing algorithm.

关键词： device-to-device (D2D) communication energy-efficiency multi-hop relay-assisted transmission routing algorithm

Phase decomposition behavior and its effects on mechanical properties of TiNbTa0.5ZrAl0.5 refractory high entropy alloy

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Journal of Materials science & Technology 2021年第7期66卷 10-20页

作者： Yuankui Cao Weidong Zhang Bin Liu Yong Liu Meng Du Ao Fu State Key Lab of Powder Metallurgy Central South UniversityChangsha410083China School of Materials science and Engineering Hunan UniversityChangsha410083China

The mechanical properties of refractory high entropy alloys(RHEAs) strongly depend on their phase structures. In this work, the phase stability of a BCC TiNbTa0.5ZrAl0.5 refractory high entropy alloy subjected to thermomechanical processing was evaluated, and the effects of phase decomposition on room/high temperature mechanical properties were quantitatively studied. It was found that, the thermomechanical processing at 800℃and 1200℃ leads to phase decomposition in the TiNbTa0.5ZrAl0.5 alloy. The phase decomposition is caused by the rapid rising of free energy of the primary BCC phase. The effect of the precipitates on room temperature strength is determined by the competition between the increasing in precipitation strengthening and the decreasing in solid solution strengthening. But at high temperatures(800-1200℃), the phase decomposition causes significant reduction in strength, mainly due to the grain boundary sliding and the decreasing in solid solution strengthening.

关键词： High entropy alloy Thermomechanical processing Precipitation Mechanical property Strengthening mechanism

Improved H_∞ control for networked control systems with network-induced delay and packet dropout

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Journal of Central South University 2016年第5期23卷 1215-1223页

作者：李冰武俊峰黄玲 School of Measurement-control Technology and Communications Engineering Harbin University of Science and Technology College of Electrical and Information Engineering Heilongjiang University of Science and Technology

The H_∞ performance analysis and controller design for linear networked control systems(NCSs) are *** NCSs are considered a linear continuous system with time-varying interval input delay by assuming that the sensor is time-driven and the logic Zero-order-holder(ZOH) and controller are *** on this model,the delay interval is divided into two equal subintervals for H_∞ performance *** improved H_∞ stabilization condition is obtained in linear matrix inequalities(LMIs) framework by adequately considering the information about the bounds of the input delay to construct novel Lyapunov–Krasovskii functionals(LKFs).For the purpose of reducing the conservatism of the proposed results,the bounds of the LKFs differential cross terms are properly estimated without introducing any slack matrix ***,the H_∞ controller is reasonably designed to guarantee the robust asymptotic stability for the linear NCSs with an H_∞ performance level γ.Numerical simulation examples are included to validate the reduced conservatism and effectiveness of our proposed method.

关键词： H ∞ performance networked control systems packet dropout network-induced delay

Tire Road Friction Coefficient Estimation:Review and Research Perspectives

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Chinese Journal of Mechanical Engineering 2022年第2期35卷 1-11页

作者： Yan Wang Jingyu Hu Fa’an Wang Haoxuan Dong Yongjun Yan Yanjun Ren Chaobin Zhou Guodong Yin School of Mechanical Engineering Southeast UniversityNanjing 211189China College of Mechano-Electronic Engineering Lanzhou University of TechnologyLanzhouGansu 730050China

Many surveys on vehicle traffic safety have shown that the tire road friction coefficient(TRFC)is correlated with the probability of an *** probability of road accidents increases sharply on slippery road ***,accurate knowledge of TRFC contributes to the optimization of driver maneuvers for further improving the safety of intelligent vehicles.A large number of researchers have employed different tools and proposed different algorithms to obtain *** work investigates these different methods that have been widely utilized to estimate *** methods are divided into three main categories:off-board sensors-based,vehicle dynamics-based,and data-driven-based *** review provides a comparative analysis of these methods and describes their strengths and ***,some future research directions regarding TRFC estimation are presented.

关键词： Intelligent vehicles Tire road friction coefficient(TRFC) Off-board sensors-based method Vehicle dynamics-based method Data-driven-based method

Composite polymer electrolyte reinforced by graphitic carbon nitride nanosheets for room-temperature all-solid-state lithium batteries

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Chinese Journal of Chemical Engineering 2023年第2期54卷 257-263页

作者： Qingyue Han Suqing Wang Wenhan Kong Bing Ji Haihui Wang School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510640China Beijing Key Laboratory for Membrane Materials and Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

By virtue of the flexibility and safety, polyethylene oxide(PEO) based electrolytes are regarded as an appealing candidate for all-solid-state lithium batteries. However, their application is limited by the poor ionic conductivity at room temperature, narrow electrochemical stability window and uncontrolled growth of lithium dendrite. To alleviate these problems, we introduce the ultrathin graphitic carbon nitride nanosheets(GCN) as advanced nanofillers into PEO based electrolytes(GCN-CPE). Benefiting from the high surface area and abundant surface N-active sites of GCN, the GCN-CPE displays decreased crystallinity and enhanced ionic conductivity. Meanwhile, Fourier transform infrared and chronoamperometry studies indicate that GCN can facilitate Li+migration in the composite electrolyte. Additionally, the GCN-CPE displays an extended electrochemical window compared with PEO based electrolytes. As a result, Li symmetric battery assembled with GCN-CPE shows a stable Li plating/stripping cycling performance, and the all-solid-state Li/LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NCM622) batteries using GCN-CPE exhibit satisfactory cyclability and rate capability in a voltage range of 3-4.2 V at 30 ℃.

关键词： Electrolytes Polymers Graphitic carbon nitride nanosheets Composites Room temperature All-solid-state battery

Theoretical insights into strong intrinsic piezoelectricity of blue-phosphorus-like group-IV monochalcogenides

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Nano Research 2022年第1期15卷 209-216页

作者： Yuxin Dai Xiaoli Zhang Yu Cui Mengyuan Li Yao Luo Fan Jiang Renqiang Zhao Yucheng Huang College of Chemistry and Material science Key Laboratory of Electrochemical Clean Energy of Anhui Higher Education InstitutesThe Key Laboratory of Functional Molecular SolidsMinistry of EducationAnhui Laboratory of Molecule-Based MaterialsAnhui Normal UniversityWuhu 241000China

On the basis of known structures of 13-GeTe bulk and the derived monolayer,we proposed a series of structural analogues MXs(M=Ge,Sn;X=S,Se,Te)with an intrinsic built-in electric field via a substitution *** first-principles calculations,we demonstrated that these MX monolayers and bulks are thermodynamically,dynamically and mechanically stable,and the stabilities of bulks are more robust than the monolayer *** calculations showed that the monolayers have large band gaps ranging from 2.38 to 3.27 eV while the bulks have pronounced small band gaps ranging from 0.06 to 0.78 *** calculated piezoelectric coefficients d11 for the MX monolayers are in the range from 6.6 to 10.9 ***,the calculated d33 for the MX bulks are as high as 40.3-213.7 pm/*** correlating atomic polarizability,atomic mass,relative ion motion,Bader charge and lattice parameters,we proposed an empirical model to estimate the piezoelectric coefficients for the two-dimensional:(2D)MXs,where a nice match between the estimated ones and the calculated ones was *** versatile electronic propertiesand large piezoelectric coefficients endow MXs a broad prospect of application in optoelectronic and piezoelectric devices,and the revealed underlying mechanisms offer valuable guidelines for seeking novel piezoelectrics.

关键词： piezoelectricity Janus density functional theory electronic property blue-phosphorus group-IV monochalcogenides

Synthesis of cell-penetrated nitrogen-doped carbon dots by hydrothermal treatment of eggplant sepals

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science china Chemistry 2016年第7期59卷 836-842页

作者： Yichen Wang Xiue Jiang State Key Laboratory of Electro analytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Science Department of Electrical and Computer Engineering McGill University

Novel nitrogen doped carbon quantum dots were successfully fabricated by a hydrothermal method wxth eggplam sepals as carbon source. The carbon materials were characterized by transmission electron microscopy （TEM）, UV-Vis adsorption, Fourier-transformed infrared spectroscopy （FTIR）, fluorescence and the X-ray photoelectron spectroscopy （XPS） measurements, respectively. The carbon quantum dots showed excellent photoluminescence property with high stability in phosphate buffer solution with different pH values from 5 to 9, even in the cell culture medium supplied with the fetal bovine serum. Meanwhile, we also studied the interaction of carbon quantum dots with living HeLa cells with confocal microscopy. Our results indicated that the carbon quantum dots can enter the living HeLa cells by cellular penetration.

关键词： carbon quantum dots eggplant sepals fluorescence bioimaging cellular penetration

S-Allylmercaptocysteine improves alcoholic liver disease partly through a direct modulation of insulin receptor signaling

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Acta Pharmaceutica Sinica B 2021年第3期11卷 668-679页

作者： Pingping Luo Ming Zheng Rui Zhang Hong Zhang Yingxia Liu Wei Li Xiaoming Sun Qian Yu George LTipoe Jia Xiao Clinical Medicine Research Institute the First Affiliated Hospital of Jinan UniversityGuangzhou 510632China Department of Interventional Surgery the First Affiliated Hospital of Jinan UniversityGuangzhou 510632China State Key Discipline of Infectious Diseases Department of Infectious DiseasesShenzhen Third People’s HospitalShenzhen 518000China Faculty of Pharmaceutical sciences Toho UniversityChiba 2748510Japan School of Integrative Pharmacy Institute of Integrative Pharmaceutical ResearchGuangdong Pharmaceutical UniversityGuangzhou 510000China School of Biomedical sciences Li Ka Shing Faculty of Medicinethe University of Hong KongHong Kong 999077China

Alcoholic liver disease(ALD) causes insulin resistance, lipid metabolism dysfunction, and inflammation. We investigated the protective effects and direct regulating target of S-allylmercaptocysteine(SAMC) from aged garlic on liver cell injury. A chronic ethanol-fed ALD in vivo model(the NIAAA model) was used to test the protective functions of SAMC. It was observed that SAMC(300 mg/kg, by gavage method) effectively ameliorated ALD-induced body weight reduction, steatosis,insulin resistance, and inflammation without affecting the health status of the control mice, as demonstrated by histological, biochemical, and molecular biology assays. By using biophysical assays and molecular docking, we demonstrated that SAMC directly targeted insulin receptor(INSR) protein on the cell membrane and then restored downstream IRS-1/AKT/GSK3 b signaling. Liver-specific knock-down in mice and siRNA-mediated knock-down in AML-12 cells of Insr significantly impaired SAMC(250 mmol/L in cells)-mediated protection. Restoration of the IRS-1/AKT signaling partly recovered hepatic injury and further contributed to SAMC’s beneficial effects. Continuous administration of AKT agonist and recombinant IGF-1 in combination with SAMC showed hepato-protection in the mice ***-term(90-day) administration of SAMC had no obvious adverse effect on healthy mice. We conclude that SAMC is an effective and safe hepato-protective complimentary agent against ALD partly through the direct binding of INSR and partial regulation of the IRS-1/AKT/GSK3 b pathway.

关键词： Alcoholic liver disease S-Allylmercaptocysteine Insulin receptor Insulin resistance IRS-1 AKT GSK3b Safety