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Nuclear Science and Techniques 2023年第2期34卷 128-138页

作者： xing‑Chao Shen yuan Fu Jian‑yu Zhang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

The high-temperature molten salt pump is the core equipment in a molten salt reactor that drives the flow of the molten salt *** stability is key to the continuous and reliable operation of the molten salt pump,and the liquid seal at the wear ring can affect the dynamic characteristics of the rotor *** the molten salt pump is operated in the hightemperature molten salt medium,thermal deformation of the submerged parts inevitably occurs,changing clearance between the stator and rotor,affecting the leakage and dynamic characteristics of the *** this study,the seal leakage,seal dynamic characteristics,and rotor system dynamic characteristics are simulated and analyzed using finite element simulation software based on two cases of considering the effect of seal thermal deformation effect or *** results show a significant difference in the leakage characteristics and dynamic characteristics of the seal obtained by considering the effect of seal thermal deformation and neglecting the effect of thermal *** leakage flow rate decreases,and the first-order critical speed of the seal-bearing-rotor system decrease after considering the seal’s thermal deformation.

关键词： High-temperature molten salt pump Seal thermal deformation Leakage characteristics Seal dynamic characteristics Critical speed

Baicalin,silver titanate,Bletilla striata polysaccharide and carboxymethyl chitosan in a porous sponge dressing for burn wound healing

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Journal of Integrative Medicine 2023年第5期21卷 487-495页

作者： Yan-rong Gong Cheng Zhang xing Xiang Zhi-bo Wang yu-qing Wang Yong-hua su Hui-qing Zhang School of Traditional Chinese Medicine Naval Medical UniversityShanghai 200433China Department of Dermatology Shuguang HospitalShanghai University of Traditional Chinese MedicineShanghai 201203China Department of Dermatology Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghai 200437China Institute of Dermatology Shanghai Academy of Traditional Chinese MedicineShanghai 201203China

Objective This study tests the efficacy of Bletilla striata polysaccharide(BSP),carboxymethyl chitosan(CMC),baicalin(BA)and silver titanate(ST)in a wound dressings to fight infection,promote healing and provide superior *** The antibacterial activity of BA and ST was evaluated in vitro using the inhibition zone ***/ST/BSP/CMC porous sponge dressings were prepared and *** biocompatibility of BA/ST/BSP/CMC was assessed using the cell counting kit-8 *** therapeutic effect of BA/ST/BSP/CMC was further investigated using the dorsal skin burn model in Sprague-Dawley *** The wound dressing had good antibacterial activity against Escherichia coli and Staphylococcus aureus through BA and ST,while the combination of BSP and CMC played an important role in promoting wound *** BA/ST/BSP/CMC porous sponge dressings were prepared using a freeze-drying method with the concentrations of BA and ST at 20 and 0.83 mg/mL,respectively,and the optimal ratio of 5%BSP to 4%CMC was 1:*** average porosity,water absorption and air permeability of BA/ST/BSP/CMC porous sponge dressings were measured to be 90.43%,746.1%and 66.60%,*** treatment for 3 and 7 days,the healing rates of the BA/ST/BSP/CMC group and BA/BSP/CMC group were significantly higher than those of the normal saline(NS)group and silver sulfadiazine(SSD)group(P<0.05).Interleukin-1βexpression in the BA/ST/BSP/CMC group at 1 and 3 days was significantly lower than that in the other three groups(P<0.05).After being treated for 3 days,vascular endothelial growth factor expression in the BA/BSP/CMC group and BA/ST/BSP/CMC group was significantly higher than that in the NS group and SSD group(P<0.05).Inspection of histological sections showed that the BA/ST/BSP/CMC group and BA/BSP/CMC group began to develop scabbing and peeling of damaged skin after 3 days of treatment,indicating accelerated healing relative to the NS group and SSD *** The opt

关键词： Wound dressing Baicalin Bletilla striata polysaccharide Silver titanate Carboxymethylchitosan

Extraction of copper from copper-bearing biotite by ultrasonic-assisted leaching

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International Journal of Minerals,Metallurgy and Materials 2022年第2期29卷 212-217页

作者： Baoqiang yu Jue Kou Chunbao sun Yi xing School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China

Copper-bearing biotite is a refractory copper mineral found on the surface of the Zambian *** is a copper oxide from which copper is extracted by various methods,especially by *** is the process of extracting a substance from a solid material dissolved in a *** improve the efficiency of the leaching process by a more effective method,a new method called ultrasonic-assisted acid leaching is proposed and applied in this *** with regular acid leaching,the ultrasound method reduced the leaching time from 120 to 40 min,and sulfuric acid concentration reduced from 0.5 to 0.3 mol·L^(-1).Besides,leaching temperature could be reduced from 75 to 45°C at the leaching rate of 78%.The mechanism analysis indicates that an ultrasonic wave can cause the delamination of a copper-bearing biotite and increase its specific surface area from 0.55 to 1.67 m^(2)·g^(-1).The results indicate that copper extraction from copper-bearing biotite by ultrasonic-assisted acid leaching is more effective than regular acid *** study proposes a promising method for recycling valuable metals from phyllosilicate minerals.

关键词： ultrasonic wave copper extraction delamination copper-bearing biotite

Multiscale observation in wide-spatial radar surveillance based on coherent FDA design

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Science China(Information Sciences) 2024年第2期67卷 232-252页

作者： Lei yu Feng HE Yi su College of Electronics Science National University of Defense Technology

Wide-spatial radar surveillance missions are challenging tasks, requiring an increased power budget and agility in transmission aimed at extracting information from multiple targets in different environments. These requirements necessitate high transmitting degrees of freedom(DOF) to achieve the objective of multiscale observation for specific tasks in specialized regions of interest. Herein, we exploit the multiscale observation ability in wide-spatial radar surveillance based on frequency diverse array(FDA)radar. The proposed method facilitates spatial anisotropic control of multiple radar resources, including the transmitting waveforms, beampattern, and bandwidth. By utilizing a coherent FDA radar, we offer principles for the selection of baseband waveforms, in addition to the quantitative design of the beampattern gain and optimal bandwidth from the perspective of detection. The feasibility of the proposed method is validated through numerical experiments, thus indicating the potential in wide-spatial radar surveillance. Moreover,this work can be regarded as a preliminary attempt to gauge the efficacy of the computational array, a novel academic concept.

关键词： multi-scale observation wide-spatial surveillance frequency diverse array (FDA) beampattern synthesis frequency diversity gain computational array

A novel signal feature extraction technology based on empirical wavelet transform and reverse dispersion entropy

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Defence Technology（防务技术） 2021年第5期17卷 1625-1635页

作者： yu-xing Li Shang-bin Jiao Xiang Gao School of Automation and Information Engineering Xi’an University of TechnologyXi’an710048China School of Electrical Engineering Xi’an University of TechnologyXi’an710048China

Feature extraction is an important part of signal processing,which is significant for signal detection,classification,and *** nonlinear dynamic analysis method can extract the nonlinear characteristics of signals and is widely used in different *** dispersion entropy(RDE)proposed by us recently,as a nonlinear dynamic analysis method,has the advantages of fast computing speed and strong anti-noise ability,which is more suitable for measuring the complexity of signal than traditional permutation entropy(PE)and dispersion entropy(DE).Empirical wavelet transform(EWT),based on the theory of wavelet analysis,can decompose a complex non-stationary signal into a number of empirical wavelet functions(EWFs)with compact support set spectrum,which has better decomposition performance than empirical mode decomposition(EMD)and its improved *** the advantages of RDE and EWT,on the one hand,we introduce EWT into the field of underwater acoustic signal processing and fault diagnosis to improve the signal decomposition accuracy;on the other hand,we use RDE as the features of EWFs to improve the signal separability and ***,we propose a novel signal feature extraction technology based on EWT and RDE in this *** results show that the proposed feature extraction technology can effectively extract the complexity features of actual ***,it also has higher distinguishing ability for different types of signals than five latest feature extraction technologies.

关键词： Feature extraction Empirical mode decomposition Empirical wavelet transform Permutation entropy Reverse dispersion entropy

Giant magnetoresistance in antiferromagnetic Mn2Au-based tunnel junction

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Science China(Physics,Mechanics & Astronomy) 2020年第9期63卷 111-117页

作者： xing-Tao Jia Xiao-Lin Cai yu Jia School of Physics and Electronic Information Engineering Henan Polytechnic UniversityJiaozuo 454000China International Laboratory for Quantum Functional Materials of Henan School of PhysicsZhengzhou UniversityZhengzhou 450001China Key Laboratory for Special Functional Materials of Ministry of Education School of Materials Science and EngineeringHenan UniversityKaifeng 475004China

Recent studies on the electrical switching of tetragonal antiferromagnet(AFM)via Neél spin-orbit torque have paved the way for the economic use of antiferromagnetic *** most difficult obstacle that presently limits the application of antiferromagnetic materials in spintronics,especially in memory storage applications,could be the small and fragile magnetoresistance(MR)in the AFM-based *** this study,we investigated the spin transports in Mn2Au-based tunnel junctions based on the first-principle scattering *** MRs more than 1000%are predicted in some Fe/MgO/Ag/Mn2Au/Ta junctions that are about the same order as that in an MgO-based ferromagnetic tunnel junction with same barrier *** interplay of the spin filtering effect,the quantum well resonant states,and the interfacial resonant states could be responsible for the unusual giant and robust MRs observed in these Mn2Au-based junctions.

关键词： Mn2Au giant magnetoresistance tunnel junction

Zinc finger protein ZFP36 and pyruvate dehydrogenase kinase PDK1 function in ABA-mediated aluminum tolerance in rice

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The Crop Journal 2024年第5期12卷 1483-1495页

作者： Nana su Yanning Gong Xin Hou xing Liu Sergey Shabala Vadim Demidchik Min yu Mingyi Jiang Liping Huang College of Life Sciences Nanjing Agricultural UniversityNanjing 210095JiangsuChina International Research Center for Environmental Membrane Biology College of Food Science and EngineeringFoshan UniversityFoshan 528000GuangdongChina Tasmania Institute of Agriculture University of TasmaniaHobartTAS 7001Australia Department of Plant Cell Biology and Bioengineering Biological FacultyBelarusian State UniversityMinsk 220030Belarus College of Life Sciences Wuhan UniversityWuhan 430072HubeiChina

Aluminum(Al)toxicity poses a significant constraint on field crop yields in acid *** finger protein36(ZFP36)is well-documented for its pivotal role in enhancing tolerance to both drought and oxidative stress in *** study unveils a novel function of ZFP36 modulated by abscisic acid(ABA)-dependent mechanisms,specifically aimed at alleviating Al toxicity in *** Al stress,the expression of ZFP36significantly increased through an ABA-dependent *** down ZFP36 heightened Al sensitivity,while overexpressing ZFP36 conferred increased resistance to Al ***,our investigations revealed a physical interaction between ZFP36 and pyruvate dehydrogenase kinase 1 in rice(OsPDK1).Biochemical assays further elucidated that OsPDK1 phosphorylates ZFP36 at the amino acid site 73–*** experiments demonstrated that ZFP36 positively regulates the expression of ascorbate peroxidases(OsAPX1)and OsALS1 by binding to specific elements in their upstream segments in *** genetic and phenotypic analyses,we unveiled that OsPDK1 influences ABA-triggered antioxidant defense to alleviate Al toxicity by interacting with *** summary,our study underscores that pyruvate dehydrogenase kinase 1(OsPDK1)phosphorylates ZFP36 to modulate the activities of antioxidant enzymes via an ABA-dependent pathway,influencing tolerance of rice to soil Al toxicity.

关键词： ZFP36 OsPDK1 ABA signaling Aluminum tolerance

Numerical simulation of flow and heat transfer of n-decane in sub-millimeter spiral tube at supercritical pressure

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Chinese Journal of Chemical Engineering 2023年第8期60卷 173-185页

作者： Jiahao xing Huaizhi Han Ruitian yu Wen Luo School of Chemical Engineering Sichuan UniversityChengdu 610065China Engineering Research Center of Combustion and Cooling for Aerospace Power Ministry of EducationSichuan UniversityChengdu 610065China

The flow and heat transfer characteristics of n-decane in the sub-millimeter spiral tube(SMST) at supercritical pressure(p = 3 MPa) are studied by the RNG k-ε numerical model in this paper. The effects of various Reynolds numbers(Re) and structural parameters pitch(s) and spiral diameter(D) are *** indicate that the average Nusselt numberNu and friction factorNu increase with an increase in Re, and decrease with an increase in D/d(tube diameter). In terms of the structural parameter s/d, it is found that as s/d increases, the Nu first increase, and then decrease. and the critical structural parameter is s/d = 4. Compared with the straight tube, the SMST can improve Nu by 34.8% at best, while it can improve Nu by 102.1% at most. In addition, a comprehensive heat transfer coefficient is applied to analyze the thermodynamic properties of SMST. With the optimal structural parameters of D/d = 6 and s/d = 4, the comprehensive heat transfer factor of supercritical pressure hydrocarbon fuel in the SMST can reach 1.074. At last, correlations of the average Nusselt number and friction factor are developed to predict the flow and heat transfer of n-decane at supercritical pressure.

关键词： sub-millimeter spiral tube supercritical pressure Numerical simulation Heat transfer performance

The penetrating depth analysis of Lunar Penetrating Radar onboard Chang＇e-3 rover

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Research in Astronomy and Astrophysics 2017年第5期17卷 79-90页

作者： Shu-Guo xing Yan su Jian-Qing Feng Shun Dai yuan Xiao Chun-yu Ding Chun-Lai Li National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China University of Chinese Academy of Sciences Beijing 100049 China

Lunar Penetrating Radar（LPR） has successfully been used to acquire a large amount of scientific data during its in-situ detection. The analysis of penetrating depth can help to determine whether the target is within the effective detection range and contribute to distinguishing useful echoes from ***, this study introduces two traditional methods, both based on a radar transmission equation, to calculate the penetrating depth. The only difference between the two methods is that the first method adopts system calibration parameters given in the calibration report and the second one uses high-voltage-off radar data. However, some prior knowledge and assumptions are needed in the radar equation and the accuracy of assumptions will directly influence the final results. Therefore, a new method termed the Correlation Coefficient Method（CCM） is provided in this study, which is only based on radar data without any a priori assumptions. The CCM can obtain the penetrating depth according to the different correlation between reflected echoes and noise. To be exact, there is a strong correlation in the useful reflected echoes and a random correlation in the noise between adjacent data traces. In addition, this method can acquire a variable penetrating depth along the profile of the rover, but only one single depth value can be obtained from traditional methods. Through a simulation, the CCM has been verified as an effective method to obtain penetration depth. The comparisons and analysis of the calculation results of these three methods are also implemented in this study. Finally, results show that the ultimate penetrating depth of Channel 1 and the estimated penetrating depth of Channel 2 range from 136.9 m to 165.5 m（ε_r = 6.6） and from 13.0 m to 17.5 m（ε_r = 2.3）, respectively.

关键词： penetrating Lunar rover lunar assumptions calibration ultimate traces Correlation verified

Measurement-device-independent quantum secret sharing and quantum conference based on Gaussian cluster state

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Science China(Information Sciences) 2019年第7期62卷 196-209页

作者： yu WANG Caixing TIAN Qi su Meihong WANG Xiaolong su State Key Laboratory of Cryptology State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-Electronics Shanxi University Collaborative Innovation Center of Extreme Optics Shanxi University

Cluster state is the basic resource for one-way quantum computation and a valuable resource for establishing quantum network, because it has a flexible and varied composition form. We present measurement-device-independent quantum secret sharing(QSS) and quantum conference(QC) schemes based on continuous variable(CV) four-mode cluster state with different structures. The users of the protocol prepare their own Einstein-Podolsky-Rosen(EPR) states, respectively. One mode of these EPR states is sent to an untrusted relay where a generalized Bell measurement creates different types of CV cluster states among four users, while the other mode is kept at their own station. We show that a shared secret key for QSS and QC schemes is distilled based on the shared quantum correlation among four users. QC and four users QSS are implemented based on the star shape CV cluster state. QSS with three users are implemented based on the linear or square shape CV cluster states. The results show that the secure transmission distance for an asymmetric network, where the transmission distances between the users and relay are different, is longer than that of a symmetric network, where the transmission distances between the users and relay are the same. The presented schemes provide concrete references for establishing quantum network with the CV cluster state.

关键词： measurement-device-independent cluster state quantum network continuous variable quantum secret sharing