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Polaron and molecular states of a spin-orbit coupled impurity in a spinless Fermi sea

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Chinese Physics B 2021年第10期30卷 447-456页

作者： Hong-hao Yin Tian-Yang xie An-Chun Ji qing Sun Department of Physics Capital Normal UniversityBeijing 100048China

We investigate the polaron and molecular states of a fermionic atom with one-dimensional spin-orbit coupling(SOC)coupled to a three-dimensional spinless Fermi *** of the interplay among the SOC,Raman coupling and spinselected interatomic interactions,the polaron state induced by the spin-orbit coupled impurity exhibits quite unique *** find that the energy dispersion of the polaron generally has a double-minimum structure,which results in a finite center-of-mass(c.m.)momentum in the ground state,different from the zero-momentum polarons where SOC are introduced into the majority *** further tuning the parameters such as the atomic interaction strength,a discontinuous transition between the polarons with different *** may occur,signaled by the singular behavior of the quasiparticle residue and effective mass of the ***,the molecular state as well as the polaron-to-molecule transition is also strongly affected by the Raman coupling and the effective Zeeman field,which are introduced by the lasers generating SOC on the impurity *** also discuss the effects of a more general spin-dependent interaction and mass *** results would be beneficial for the study of impurity physics brought by SOC.

关键词： spin-orbit coupling polaron Fermi gas

Sleep Apnea Monitoring System Based on Commodity WiFi Devices

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Computers, Materials & Continua 2021年第11期69卷 2793-2806页

作者： Xiaolong Yang Xin Yu Liangbo xie hao Xue Mu Zhou qing Jiang School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing400065China School of Computing Technologies RMIT UniversityMelbourneVictoria3001Australia

To address the limitations of traditional sleep monitoring methods that highly rely on sleeping posture without considering sleep apnea,an intelligent apnea monitoring system is designed based on commodity WiFi in this *** utilizing linear fitting and wavelet transform,the phase error of channel state information(CSI)of the receiving antenna is eliminated,and the noise of the signal amplitude is ***,the short-time Fourier transform(STFT)and sliding window method are combined to segment received wireless ***,several important statistical characteristics are extracted,and a back propagation(BP)neural network model is built to identify apnea ***,interferences caused by changes of sleeping posture are *** experimental results demonstrate that the proposed system can identify apnea state with an accuracy of over 95.6%.Furthermore,the accuracy can still reach more than 94.8%when the test environment layout is ***,the proposed system can be used as a daily apnea monitoring system at home and provide users with health information.

关键词： WiFi channel state information apnea neural network

Parametric channel modeling based OFDM channel estimation

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The Journal of China Universities of Posts and Telecommunications 2014年第5期21卷 1-8页

作者： qing hao-bo LIU Yuan-an xie Gang LIU Kai-ming LIU Fang Beijing Key Laboratory of Work Safety Intelligent Monitoring Beijing University of Posts and Telecommunications Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

A simplified parametric channel estimation approach was proposed for orthogonal frequency division multiplexing （OFDM） systems. Based on parametric channel model, this algorithm is composed of two parts： the estimation of channel parameters and channel interpolation. The exponentially embedded family （EEF） criterion is exploited to determine the number of channel paths as well as the multipath time delays. Consequently, the channel frequency responses is acquired via the estimated parameters. Additionally, the authors＇ scheme is computationally efficient owing to the needless of the eigenvalue decomposition or the estimation of signal parameters by the rotational invariance technique （ESPRIT）. Simulations are provided to validate the performance of this algorithm from perspectives of the probability of correct estimation and the mean square error （MSE）. It is demonstrated that this approach exhibits a superior performance over the existing algorithms.

关键词： channel estimation OFDM mean square error EEF criterion

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氢燃料混合动力机车能量管理策略

内燃机与配件 2024年第10期 122-124页

作者：谢嘉欣郭婉露秦庆民中车株洲电力机车有限公司湖南株洲412000

氢燃料电池在国内外轨道交通领域的应用日益增加,能量管理策略作为氢燃料电池应用中的关键内容,受到越来越多的关注。本文针对某一种氢燃料电池混合动力机车的能量管理策略设计进行阐述,着重分析混合动力系统的能量平衡控制、分级电压... 详细信息

氢燃料电池在国内外轨道交通领域的应用日益增加,能量管理策略作为氢燃料电池应用中的关键内容,受到越来越多的关注。本文针对某一种氢燃料电池混合动力机车的能量管理策略设计进行阐述,着重分析混合动力系统的能量平衡控制、分级电压控制策略以及功率分配策略,基于运行工况及规则确定具体的控制策略,控制简单明确,可实现混合动力系统的稳定输出,充分发挥氢燃料电池和动力电池的优势,保障机车动态性能,满足不同牵引功率下机车运行需求,对推动混合动力机车能量管理技术的发展具有一定意义。

关键词：氢燃料电池混合动力系统能量管理

Reaction mechanism of fluoride conversion into BF^(4-) during sulphuric acid leaching of roasted bastnaesite

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Journal of Rare Earths 2021年第2期39卷 186-193页

作者： Hongcheng Zhang Dairui xie Heng Zhang Meng Jiang hao Huang Yu wan Yang Liao Shilin Zhao College of Chemistry and Material Science Sichuan Normal UniversityChengdu 610068China Key Laboratory of Land Resources Evaluation and Monitoring in Southwest Ministry of Education of ChinaChengdu 610068China

The bastnaesite used in hydrometallurgy usually contains 7%-11% fluorine,and the conversion of fluorine into high-value products is the key to achieving green production of rare earths and improving the comprehensive utilization of *** order to recover fluorine from bastnaesite in the form of KBF4,the mechanism of F^(-)conversion to BF^(4-)in sulphuric acid leaching solution of roasted bastnaesite was studied by using Eh-pH diagram and simulation *** shows that the formation of BF^(4-)is affected by pH in the absence of rare ***^(4-)is hydrolyzed to BF3 OH-and F-when the pH is greater than 3.9,and part of F-exists as HF^(2-)when pH is lower than *** the presence of La^(3+),the formation of BF^(4-)is mainly affected by LaF_(3) when pH is greater than 0,and in the case that the pH is lower than 2,it is mainly affected by HF^(2-).When Ce4+is present in solution,CeF_(2)^(2+) can exist stably in sulphuric acid *** down the pH can reduce the stability of CeF_(2)^(2+) and increase the BF^(4-)conversion *** on these results,KBF4 was prepared in the alkaline solution of bastnaesite,and the conversion of BF^(4-)is 84.31%.This provides a theoretical basis for the recovery of fluorine from bastnaesite in the form of KBF_(4).

关键词： BF^(4-) Bastnaesite E_(h)-pH diagram Sulphuric acid leaching Rare earths

Es-SOX8 regulates the morphological changes of the sperm nucleus of Eriocheir sinensis by activating Es-BMP2 transcription

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BIOCELL 2022年第11期46卷 2399-2413页

作者： KE JIA FU-qing TAN shuANG-LI hao wan-XI YANG The Sperm Laboratory College of Life SciencesZhejiang UniversityHangzhou310058China The First Affiliated Hospital College of MedicineZhejiang UniversityHangzhou310003China

The SRY-related high mobility group(HMG)box(SOX)transcription factors participate in many physiological processes of animal growth,development,and reproduction and are related to spermatogenesis in many ***,the relationship between SOX and spermatogenesis in Eriocheir sinensis is rarely ***,we studied the role of Es-SOX8 in the spermatogenesis of *** and its possible regulation *** results demonstrated Es-SOX8 signal in both cytoplasm and nucleus of spermatogonia,spermatocytes as well as spermatids,but not in mature *** and eosin staining showed a significant increase in the number of spermatozoa with abnormal nuclear morphology in vivo,described as prominent edges and corners,after the knockdown of Es-SOX8 through RNA *** indicated a possible role of Es-SOX8 in the nuclear deformation process in the spermatogenesis of *** of the mRNA levels of Es-bone morphogenetic protein 2(BMP2)in the Es-Sox8 knocked-down testis tissue revealed significantly decreased transcription of *** immunoprecipitation results showed the binding of Es-SOX8 protein to the promoter region of ***,Es-SOX8 can directly regulate the transcription of Es-BMP2 by activating the promoter of Es-BMP2 and thus affects the sperm nucleus deformation of ***.

关键词： SOX Transcription factor Spermatogenesis BMP2

Effect of H_2 dilution on the structure and properties of nc-CrC/a-C:H coatings deposited by a hybrid beams system

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Nuclear Science and Techniques 2018年第1期29卷 118-126页

作者： Yao cai Hui-Dong Liu Zhong-Wei Hu Qiang wan Chang Luo hao Chen Yan Liu Yan-Ming Chen qing-Song Mei Bing Yang School of Power and Mechanical Engineering Wuhan University School of Materials Science and Engineering Xi'an Jiao Tong University China Datang Corporation Science and Technology Research Institute Co. Ltd. East China Branch

Nanocomposite Cr C/hydrogenated amorphous carbon(nc-CrC/a-C:H) coatings were deposited by a hybrid beams system comprised of a hollow cathode ion source and a cathodic arc ion-plating unit with varying H_2 flow rates. The influences of H_2 flow rates on the morphologies, microstructures, and properties of the coatings were systematically studied. The morphologies and microstructures of the coatings were characterized by SEM, AFM, XPS, Raman spectroscopy, GIXRD, and HRTEM. The mechanical and tribological properties were measured by a nano-indenter, scratch tester, and ball-ondisk tribometer. The wear tracks were evaluated using 3D profilometer, optical microscope, and EDS analysis. It has been found that a moderate H_2 flow rate can effectively smooth the surface, enlarge the fraction of a sp^3 bond, and improve the properties. The coating exhibits the highest hardness and elastic modulus at the H_2 flow rate of 40 sccm. A superior combination of adhesion strength,friction coefficient, and wear resistance can be achieved at the H_2 flow rate of 80 sccm.

关键词： CrC/a-C:H coating Nanocomposite H2 flow rate Hybrid beams system

Mechanical ventilation strategy for pulmonary rehabilitation based on patient-ventilator interaction

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Science China(Technological Sciences) 2021年第4期64卷 869-878页

作者： hao LiMing LI Xiao SHI Yan cai MaoLin REN shuai xie Fei LI YaNa wanG Na wanG YiXuan LUO ZuJin XU Meng School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Department of Rehabilitation The Fouth Medical Center of PLA General HospitalBeijing 100048China Department of Pulmonary and Critical Care Medicine Chinese PLA General HospitalBeijing 100039China Department of Respiratory and Critical Care Medicine Beijing Engineering Research Center of Respiratory and Critical Care MedicineBeijing Institute of Respiratory MedicineBeijing Chao-Yang HospitalCapital Medical UniversityBeijing 100043China Department of Orthopedics Chinese PLA General HospitalBeijing 100039China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China

Mechanical ventilation is an effective medical means in the treatment of patients with critically ill,COVID-19 and other pulmonary *** the mechanical ventilation and the weaning process,the conduct of pulmonary rehabilitation is essential for the patients to improve the spontaneous breathing ability and to avoid the weakness of respiratory muscles and other pulmonary functional ***,inappropriate mechanical ventilation strategies for pulmonary rehabilitation often result in weaning difficulties and other ventilator *** this article,the mechanical ventilation strategies for pulmonary rehabilitation are studied based on the analysis of patient-ventilator interaction.A pneumatic model of the mechanical ventilation system is established to determine the mathematical relationship among the pressure,the volumetric flow,and the tidal *** ventilation cycle is divided into four phases according to the different respiratory characteristics of patients,namely,the triggering phase,the inhalation phase,the switching phase,and the exhalation *** control parameters of the ventilator are adjusted by analyzing the interaction between the patient and the ventilator at different phases.A novel fuzzy control method of the ventilator support pressure is proposed in the pressure support ventilation *** to the fuzzy rules in this research,the plateau pressure can be obtained by the trigger sensitivity and the patient’s inspiratory *** experiment prototype of the ventilator is established to verify the accuracy of the pneumatic model and the validity of the mechanical ventilation strategies proposed in this *** addition,through the discussion of the patient-ventilator asynchrony,the strategies for mechanical ventilation can be adjusted *** results of this research are meaningful for the clinical operation of mechanical ***,these results provide a theoretical basis for the future research on

关键词： mechanical ventilation pulmonary rehabilitation phases division fuzzy control patient-ventilator interaction

Ectopic Expression of the Pttknl Gene Induces Alterations in the Morphology of the Leaves and Flowers in Petunia hybrida Vilm.

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Journal of Integrative Plant Biology 2005年第10期47卷 1153-1158页

作者： Xin HU qing-Feng WU Ya-Hong xie Hong RU Feng xie Xin-Yu wanG Chong-Ying wan School of Life Sciences Lanzhou University Lanzhou 730000 China Xi＇an Institute of Gardens Xi＇an 710065 China

A novel knottedl-like homeobox （knox） gene, Pttknl （Populus tremulaxtremuloides knottedl）, isolated from the cambial region of hybrid aspen, was introduced into Petunia hybrida Vilm. using the leafdisc method mediated by Agrobacterium. A series of novel phenotypes was observed in transgenic petunia plants, including the formation of ectopic spikes on the adaxial surface of corollas and small petals on the abaxial surface of corollas, fusion of floral organs, shortening of corolla midribs, the formation of tumor-like knots along the midrib on the abaxial surface and serrated lobs of corolla margins, and alterations in petal color; except for changes in the leaves and plant architecture, RT-PCR showed that the Pttknl gene was expressed in the leaves of different petunia transgenic plants, whereas no signal was detected in wild-type plants. The possible function of Pttknl in leaf and flower development is discussed.

关键词： ectopic expression knox gene novel phenotypes Petunia hybrida Pttknl gene RT-PCR.