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Understanding enhancing mechanism of Pr_(6)O_(11) and Pr(OH)_(3) in methanol electrooxidation

Journal of Rare Earths 2022年第1期40卷 85-92页

作者： Yang Yang Zhenyu Li Ying Yu Xueqiong Zhang Hang Wei Haibin Chu Inner Mongolia Engineering and Technology Research Center for Catalytic Conversion and Utilization of Carbon Resource Molecules College of Chemistry and Chemical EngineeringInner Mongolia UniversityHohhot 010021China

The presence of oxygen vacancies and hydroxyl groups are both favorable for the methanol electrooxidation on Pt-based catalysts.Understanding and differentiating the enhancing mechanism between oxygen vacancies and hydroxyl groups for high activity of Pt catalysts in methanol oxidation reaction(MOR)is essential but still challenging.Herein,we developed two kinds of co-catalyst for Pt/CNTs,Pr_(6)O_(11)is rich in oxygen vacancies but contains substantially no hydroxyl groups,while Pr(OH)_(3) possesses abundant hydroxyl groups without oxygen vacancies.After a seque nce of designed experiments,it can be found that both oxygen vacancies and hydroxyl groups can improve the performance of Pt/CNTs electrocatalysts,but the enhancing mechanism and improving degree of oxygen vacancies and hydroxyl groups for the MOR are different.Since the oxygen vacancies are more conducive to increasing the intrinsic activity of the Pt catalyst,and the hydroxyl groups play a decisive role in dehydrogenation and deproto nation of methanol,the co-catalysts with both oxygen vacancies and hydroxyl groups mixed with Pt/CNTs have higher catalytic performance.Therefore,hydroxyl-rich Pr_(6)O_(11)·xH_(2)O was prepared and used as MOR electrocatalyst after mixed with Pt/CNTs.Benefiting from the synergistic effect of oxygen vacancies and hydroxyl groups,the Pr_(6)O_(11)·xH_(2)O/Pt/CNTs shows a high peak current density of 741 mA/mg,which is three times higher than that of Pt/CNTs.These new discoveries serve as a promising strategy for the rational design of MOR catalysts with low cost and high activity.

关键词： Oxygen vacancies Hydroxyl groups Pr_(6)O_(11) Pr(OH)_(3) Methanol oxidation reaction Rare earths

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A Full Quantum Eigensolver for Quantum Chemistry Simulations

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Research 2020年第1期2020卷 111-121页

作者： Shijie wei hang Li GuiLu Long Beijing Academy of Quantum Information Sciences Beijing 100193China State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics Tsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology and School of Information Tsinghua University Beijing 100084China Frontier Science Center for Quantum Information Beijing 100084China

Quantum simulation of quantum chemistry is one of the most compelling applications of quantum computing.It is of particular importance in areas ranging from materials science,biochemistry,and condensed matter physics.Here,we propose a full quantum eigensolver(FQE)algorithm to calculate the molecular ground energies and electronic structures using quantum gradient descent.Compared to existing classical-quantum hybrid methods such as variational quantum eigensolver(VQE),our method removes the classical optimizer and performs all the calculations on a quantum computer with faster convergence.The gradient descent iteration depth has a favorable complexity that is logarithmically dependent on the system size and inverse of the precision.Moreover,the FQE can be further simplified by exploiting a perturbation theory for the calculations of intermediate matrix elements and obtaining results with a precision that satisfies the requirement of chemistry application.The full quantum eigensolver can be implemented on a near-term quantum computer.With the rapid development of quantum computing hardware,the FQE provides an efficient and powerful tool to solve quantum chemistry problems.

关键词： convergence quantum iteration

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Theoretical Analysis of the Galloping Energy Harvesters under Bounded Random Parameter Excitation

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Computer Modeling in Engineering & Sciences 2023年第11期137卷 1731-1747页

作者： hang Deng Jimin Ye wei Li Dongmei Huang School of Mathematics and Statistics Xidian UniversityXi’an710071China

In this paper,the response properties of galloping energy harvesters under bounded random parameter excitation are studied theoretically.The first-order approximate solution of the galloping energy harvester is derived by applying the multi-scales method.The expression for the largest Lyapunov exponent that determines the trivial solution is derived,and the corresponding simulation diagrams,including the largest Lyapunov exponent diagrams and time domain diagrams,verify our results.Then the steady-state response moments of the nontrivial solution are studied using the moment method,and the analytical expressions for the first-order and second-order moments of the voltage amplitude are obtained,respectively.The corresponding results show that wind speed enhances the steady-state response moments of the voltage amplitude.Meanwhile,the voltage output can be controlled by adjusting the cubic coefficient.To further verify the response characteristics of the galloping energy harvester,the stationary probability density functions of the displacement and velocity are obtained by the Monte-Carlo simulation method.The results show that the wind speed enhances the displacement of the bluff and the damping ratios should be reduced asmuch as possible to improve the performance.What’smore,the piezoelectric materials also impact the performance of the energy harvester.

关键词： Galloping energy harvester multi-scales method parametric excitation stability

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Bifurcation control of solid angle car-following model through a time-delay feedback method

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浙江大学学报(英文版)A辑:应用物理与工程 2023年第9期24卷 828-840页

作者： Qun JI Hao LYU hang YANG Qi wei Rongjun CHENG Faculty of Maritime and Transportation Ningbo UniversityNingbo 315211China Ningbo University of Finance&Economics Ningbo 315175China

In order to alleviate unstable factor-caused bifurcation and reduce oscillations in traffic flow,a feedback control with consideration of time delay is designed for the solid angle model(SAM).The stability and bifurcation condition of the new SAM is derived through linear analysis and bifurcation analysis,and then accurate range of stable region is obtained.In order to explore the mechanism of the influence of multiple parameter combinations on the stability of controlled systems,a definite integral stabilization method is provided to determine the stable interval of time delay and feedback gain.Numerical simulations are explored to verify the feasibility and effectiveness of the proposed model,which also demonstrate that feedback gain and delay are two key factors to alleviate traffic congestion in the SAM.

关键词： Solid angle model(SAM) Time-delay Hopf bifurcation Feedback control Parameter calibration

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A numerical study of segmented cooling-stream injection in supersonic film cooling

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Chinese Journal of Aeronautics 2022年第6期35卷 156-171页

作者： hang NI Mingjun WANG Peixue JIANG wei PENG Yinhai ZHU Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy TechnologyKey Laboratory of Advanced Reactor Engineering and Safety of Ministry of EducationTsinghua UniversityBeijing 100084China School of Nuclear Science and Technology Xi’an Jiaotong UniversityXi’an 710049China Department of Energy and Power Engineering Key Laboratory for Thermal Science and Power Engineering of Ministry of EducationTsinghua UniversityBeijing 100084China Tsinghua University-Zhang Jiagang Joint Institute for Hydrogen Energy and Lithium-Ion Battery Technology Tsinghua UniversityBeijing 100084China

The present study proposes a segmented cooling-stream injection structure based on a certain coolant mass flow rate,and numerically investigates the effect of segmented cooling-stream injection on supersonic film cooling.The results indicate that without shock-wave impingement and with helium as the coolant,segmented cooling-stream injection can reduce the mixing between the mainstream and the cooling stream to produce better cooling performance than single injection,especially at larger coolant Mach numbers.However,with nitrogen as the coolant,the cooling effect of the segmented-injection system is very close to that of the single-injection system.Mixing at the impinging region is enhanced significantly when there is an incident shock wave.When the shock wave impinges between the two coolant inlets,segmented cooling-stream injection improves film cooling effectiveness in the midstream and downstream regions more than single injection because only part of the cooling stream undergoes the enhanced mixing effect of the shock wave.The advantage of segmented injection is reduced when the impinging region is behind the second coolant inlet.The further downstream the impinging region,the smaller the associated advantage.

关键词： Film cooling Mach number Segmented injection Shock wave Supersonic flow

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Genomic landscape of T-cell lymphoblastic lymphoma

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Chinese Journal of Cancer Research 2022年第2期34卷 83-94页

作者： Zhaoming Li Yue Song Mingzhi Zhang Yiming wei hang Ruan Department of Oncology the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China State Key Laboratory of Esophageal Cancer Prevention&Treatment and Henan Key Laboratory for Esophageal Cancer Research the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China

Objective: T-cell lymphoblastic lymphoma(T-LBL) is an aggressive neoplasm of precursor T cells, however,detailed genome-wide sequencing of large T-LBL cohorts has not been performed due to its rarity. The purpose of this study was to identify putative driver genes in T-LBL.Methods: To gain insight into the genetic mechanisms of T-LBL development, we performed whole-exome sequencing on 41 paired tumor-normal DNA samples from patients with T-LBL.Results: We identified 32 putative driver genes using whole-exome sequencing in 41 T-LBL cases, many of which have not previously been described in T-LBL, such as Janus kinase 3(JAK3), Janus kinase 1(JAK1), Runtrelated transcription factor 1(RUNX1) and Wilms’ tumor suppressor gene 1(WT1). When comparing the genetic alterations of T-LBL to T-cell acute lymphoblastic leukemia(T-ALL), we found that JAK-STAT and RAS pathway mutations were predominantly observed in T-LBL(58.5% and 34.1%, respectively), whereas Notch and cell cycle signaling pathways mutations were more prevalent in T-ALL. Notably, besides notch receptor 1(NOTCH1), mutational status of plant homeodomain(PHD)-like finger protein 6(PHF6) was identified as another independent factor for good prognosis. Of utmost interest is that co-existence of PHF6 and NOTCH1 mutation status might provide an alternative for early therapeutic stratification in T-LBL.Conclusions: Together, our findings will not only provide new insights into the molecular and genetic mechanisms of T-LBL, but also have tangible implications for clinical practice.

关键词： T-cell lymphoblastic lymphoma PHF6 NOTCH1 mutation

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Oral administration of asparagine and 3-indolepropionic acid prolongs survival time of rats with traumatic colon injury

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Military Medical Research 2023年第1期10卷 78-93页

作者： Bo Cao Rui-Yang Zhao hang-hang Li Xing-Ming Xu Hao Cui Huan Deng Lin Chen Bo wei Department of General Surgery the First Medical CenterChinese PLA General HospitalBeijing 100853China Medical School of Chinese PLA Beijing 100853China

Background: Traumatic colon injury(TCI) is a common disease during wartime. Prolongation of posttraumatic survival time is an effective approach to patient outcome improvement. However, there is a lack of basic research in this field.This study aimed to elucidate the mechanisms underlying TCI progression and to develop novel regimens to buy time for TCI patients on the battlefield.Methods: A total of 669 Sprague–Dawley rats were used in this study. Surgical colon incision was performed to generate the TCI rat model. The landscape of colon microbiota compositions was depicted using 16S rRNA sequencing and metabolites in the intestinal contents were detected by metabolomics profiling. The signaling transduction in the intestinal epithelium was investigated using antibody microarrays and Western blotting. The enzyme-linked immunosorbent assay(ELISA) was conducted to measure the levels of interleukin-6 and tumor necrosis factor-α in intestines and plasma for the detection of inflammatory responses. Diamine oxidase, D-lactate and endotoxin in plasma and protein expression of zonula occludens 1 and occludin were selected as the indicators of intestinal barrier permeability. To investigate alterations of microbiota symbiosis, the relative abundances of specific bacterial genera were detected using quantitative real-time PCR(qRT-PCR).Results: As a type of lethal injury, TCI induced acute disruption of intestinal homeostasis, characterized by inflammatory responses, intestinal barrier hyperpermeability and microbiota dysbiosis(P<0.05). Significant alterations in bacterial metabolic patterns were detected with decreases in many metabolites. After a series of screenings,we found that oral administration of asparagine(Asn) and 3-indolepropionic acid(IPA) effectively prolonged posttraumatic survival time [Asn plus IPA vs. Vehicle: hazard ratio(HR)=0.105, 95%CI 0.031–0.356, P=0.0003] and restored intestinal homeostasis in TCI rats(P<0.05). Mechanistically, this combinational strategy protected the rats against TCI through syne

关键词： Traumatic colon injury Asparagine 3-Indolepropionic acid Intestinal homeostasis Intestinal microbiota Akt signaling

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Distortion minimization for multimedia transmission in NOMA HAP-UAV integrated aerial access networks

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Chinese Journal of Aeronautics 2022年第9期35卷 81-94页

作者： Guobin Zhang Zhu HAN hang XIN Xin wei Boya DI School of Electrical Engineering and Intelligentization Dongguan University of TechnologyDongguan 523808China Department of Electrical and Computer Engineering and Department of Computer Science University of HoustonTX77004USA School of Computer Science and Technology Dongguan University of TechnologyDongguan 523808China Department of Computing Imperial CollegeLondon SW72AzUK

Aerial access networks have been envisioned as a promising 6G solution to enhance the ground communication systems in both coverage and capacity. To better utilize the spectrum and fully explore different channel characteristics, this paper constructs an integrated network comprising the High Altitude Platform(HAP) and Unmanned Air Vehicles(UAVs) with the NonOrthogonal Multiple Access(NOMA) technology. In order to improve the transmission quality of images and videos, a power management scheme is proposed to minimize the distortion of the transmissions from the HAP and UAVs to the terminals. The power control is formulated as a non-convex problem constrained by the maximal transmit power and the minimal terminal rate requirements. The variable substitution and the first-order Tailor’s expansion is used to transform it into a sequence of convex problems, which are subsequently solved through the gradient projection method. Simulation demonstrates the signal distortion and error rate improvement achieved by the proposed algorithm.

关键词： Aerial Access Networks High Altitude Platform Non-Orthogonal Multiple Access Sixth-Generation Unmanned Air Vehicles

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Study on influence of key blasthole parameters on tunnel overbreak

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Underground Space 2023年第2期9卷 76-90页

作者： Zi-qiang Li Zheng Li wei-wei Huang Xuan-ming Ding hang Zhang School of Civil Engineering and Architecture Chongqing University of Science&TechnologyChongqing 401331China Key Laboratory of New Technology for Construction of Cities in Mountain Area Ministry of EducationChongqing UniversityChongqing 400045China Chongqing City Construction Investment(Group)Co. Ltd.Chongqing 400023China School of Civil Engineering Chongqing University400045China

To determine the influence of key blasthole parameters on tunnel overbreak during blasting construction,an intelligent detection sys-tem for tunnel blasting construction is independently developed.And the key blasthole parameters and overbreak of a typical section of a single line tunnel under the condition of Class V surrounding rock are analyzed and detected.The actual data obtained is compared with the results of numerical simulations and theoretical calculations.The results are as follows:(1)Quantitative analysis is performed based on the blasthole angle,opening position,and charge mass by the self-developed intelligent detection equipment for blasthole parameters,which can be used to guide the drilling construction.Intelligent scanning equipment for outline excavation can be used to image the actual excavation section in real-time and has the advantages of high precision and fast speed;(2)Tunnel overbreak can be regarded as consisting of two parts:the surrounding rock damage caused by the blasting load,and the collapse of the surrounding rock caused by the blasthole opening position.Every parameter of the peripheral hole will affect the tunnel overbreak;however,the key parameter is the blasthole opening position;(3)The distributions of the tunnel overbreak volume obtained with the theoretical analysis,finite element simulation,and measurements are basically consistent.Under the condition of Class V surrounding rock,the overbreak of this single line tunnel can reach 14.1–78.2 cm.To meet the specification requirements,the opening position and construction accuracy of the peripheral hole should be strictly controlled.

关键词： Tunnel blasting Blasthole parameters Tunnel overbreak Surrounding rock damage Smooth surface blasting

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Molecular basis of heading date control in rice

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aBIOTECH 2020年第4期1卷 219-232页

作者： Hua wei Xiling Wang hang Xu Lei Wang Key Laboratory of Plant Molecular Physiology CAS Center for Excellence in Molecular Plant SciencesInstitute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China

Flowering time is of great significance for crop reproduction,yield,and regional adaptability,which is intricately regulated by various environmental cues and endogenous signals.Genetic approaches in Arabidopsis have revealed the elaborate underlying mechanisms of sensing the dynamic change of photoperiod via a coincidence between light signaling and circadian clock,the cellular time keeping system,to precisely control photoperiodic flowering time,and many other signaling pathways including internal hormones and external temperature cues.Extensive studies in rice(Oryza sativa.),one of the short-day plants(SDP),have uncovered the multiple major genetic components in regulating heading date,and revealed the underlying mechanisms for regulating heading date.Here we summarize the current progresses on the molecular basis for rice heading date control,especially focusing on the integration mechanism between photoperiod and circadian clock,and epigenetic regulation and heading procedures in response to abiotic stresses.

关键词： Heading date Rice Photoperiod Circadian clock Epigenetic modification Abiotic stress

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