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Theoretical investigation on the cavitation bubble dynamics near three spherical particles based on Weiss theorem

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Journal of Hydrodynamics 2023年第6期35卷 1119-1130页

作者： Yu-ning Zhang Zhi-ling Ding Jing-rong Hu xiao-xiao zheng Jia-xin Yu Jin-sen Hu College of Mechanical and Transportation Engineering China University of Petroleum-BeijingBeijing102249China Beijing Key Laboratory of Process Fluid Filtration and Separation China University of Petroleum-BeijingBeijing102249China China Fire and Rescue Institute Beijing102202China Key Laboratory of Power Station Energy Transfer Conversion and System(Ministry of Education) School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China

To research the dynamics of the cavitation bubble under the interaction of particle clusters,the bubble morphological evolutionary characteristics near three equal-sized spherical particles are theoretically explored in the present study based on the Weiss theorem and the velocity potential superposition *** three particles are arranged symmetrically,and the fluid velocity field near the three particles and the cavitation bubble is ***,the effects of the bubble-particle distance and the maximum radius of the cavitation bubble on the fluid velocity are investigated,and the contribution mechanisms of the fluid velocity field constituents are *** analysis has found that:(1)The fluid velocity between the bubble and the particle is lower than that at the other locations in both the growth and collapse phases,thus the bubble cannot always maintain a standard spherical shape.(2)The bubble-particle distance and the maximum radius of the cavitation bubble are the key parameters affecting the circumferential inhomogeneity of the radial velocity of the fluid around the *** larger the maximum radius or the smaller the bubble-particle distance is,the more visible the non-circularity of the bubble morphology.(3)The image bubbles and the linear sinks contribute oppositely to the fluid velocity field,and the presence of the image bubble reduces the fluid *** the low velocity region,the image bubble is the main mechanism contributing to the effect of the particle on the fluid velocity.

关键词： Particles-bubble effects velocity potential fluid velocity bubble morphology Weiss theorem

Epilepsy and migrained-Are they comorbidity?

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Genes & Diseases 2018年第2期5卷 112-118页

作者： Jin Liao Xin Tian Hao Wang zheng xiao Neurology Department at Chongqing Medical University ChongqingChina Neurology Department at the First Affiliated Hospital of Chongqing Medical University No.1 Youyi StreetYuanjiagangYuzhong DistrictChongqingChina

Epilepsy and migraine often *** the clinical symptoms,they often have some signs of symptoms before onset;from the pathogenesis of epilepsy and migraine,both of them have a high degree of neuronal excitement and ion channel abnormalities;in terms of treatment,many antiepileptic drugs are work in *** of this indicates that they interact with each *** it is undeniable that there are interactions and relationships between them,and there are also some differences such as the different clinical episodes,the different ways of neuronal haperexcitability and the different drug treatment *** are they comorbidity?If we can better understand the correlation between seizures and migraines,then this will help develop better guidelines for clinical diagnosis and treatment.

关键词： Comorbidity CSD Epilepsy FHM Migraine

PDMS Rod-SBSE System Coupled with Gas Chromatography for Determination of PAHs in Aqueous Samples

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Chemical Research in Chinese Universities 2011年第5期27卷 742-745页

作者： CHENG Chuan-xian PEI Hai-rong LAN xiao-zheng College of Chemistry and Material Science Shandong Agricultural University Tai ＇an 2 71018 P. R. China

A method for the analysis of trace polycyclic aromatic hydrocarbons（PAHs） in aqueous samples has been established by polydimethylsiloxane（PDMS） rod aided stir bar sorptive extraction（SBSE）. The homemade PDMS rod has a size of 30 mm×3 mm o.d. with a volume of ca. 200 μL, stable in thermal desorption process. The enriched PAHs by the PDMS rod were released in a homemade thermal desorption system coupled with gas chromatography. Experimental parameters for extraction of six PAHs were optimized including extraction time, pH, ionic strength and temperature of solution. The procedure has good recoveries of 80.0%―100.3% and very low limits of detection of 4.0―33 ng/L. PAHs in rain and river water were analyzed by this method.

关键词： Polydimethylsiloxane(PDMS) rod Stir bar sorptive extraction(SBSE) Polycyclic aromatic hydrocarbon

Primary cutaneous mantle cell lymphoma:Report of a rare case

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World Journal of Clinical Cases 2020年第8期8卷 1507-1514页

作者： xiao-Dan zheng Yan-Lin Zhang Jian-Lan Xie xiao-Ge Zhou Department of Pathology Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China

BACKGROUND We describe the case of a 74-year-old man diagnosed with primary cutaneous mantle cell lymphoma(MCL),an extremely rare and controversial condition that is not included in the World Health Organization-European Organization for Research and Treatment of Cancer classification for cutaneous *** SUMMARY The patient presented diffuse cutaneous erythematous plaques and nodules throughout the *** lesions were biopsied and histopathological examination showed diffuse monomorphic lymphocyte infiltration in the dermal and subcutaneous layers,sparing the *** staining revealed CD20,cyclin-D1,CD5,and SOX-11 *** in situ hybridization showed CCND1/IGH gene *** diagnosis of primary cutaneous MCL requires ensuring that no other parts are involved;these cases require close follow-up to monitor their possible progression to systemic disease and for treating relapsed cutaneous *** this case,positron emission tomography scanning and clinical staging revealed no systemic involvement,and follow-up examination at 20 mo after diagnosis showed no evidence of systemic *** prognosis of primary cutaneous MCL is relatively *** patient received six cycles of chemotherapy,and the cutaneous manifestations presented almost complete *** Primary cutaneous MCL is rare,and its prognosis is relatively ***,correct diagnosis is a prerequisite for proper treatment.

关键词： Primary Cutaneous Mantle cell lymphoma Diagnosis Treatment Prognosis Case report

Implementation of Quantum Fourier Transform and Its Applications via Quantum-Dot Spins and Microcavity

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Communications in Theoretical Physics 2009年第9期52卷 425-430页

作者： DONG Ping zheng xiao-Hu ZHANG Gang CAO Zhuo-Liang Department of Physics Hefei Teachers College Hefei 230061 China School of Physics and Material Science Anhui University Hefei 230039 China Department of Mathematics and Physics West Anhui University Lu＇an 237012 China

A scheme for implementing discrete quantum Fourier transform is proposed via quantum dots embedded in a microcavity, and then some of its applications are investigated, i.e., Deutsch 3ozsa. algorithm and Shor＇s quantum factoring. In particular, the detailed process of implementing one^qubit Deutsch Jozsa algorithm and the factorization of N = 15 are given. The microcavity mode is only virtually excited in the whole interaction, so the effective decoherent has slight effect on the current scheme. These schemes would be an important step to fabricate a solid quantum computer.

关键词： quantum Fourier transform quantum dot quantum algorithm

Preparation of PDMS-coated microspheres by sol-gel method for sorptive extraction of PAHs

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Chinese Chemical Letters 2008年第8期19卷 996-999页

作者： Chang Guang Yang Xiang Juan Ji xiao zheng Lan College of Chemistry and Materials Science Shandong Agricultural University Taian 271018 China

In this paper, a novel SPME mode, PDMS-coated solid glass microspheres （SGMs）, were prepared by sol-gel method. Using homemade thermal desorption unit coupled with CGC-FID, six PAHs as model analytes, the performance of the new mode was characterized. The new extractive phase exhibited high thermal stability and satisfactory extraction capability. The detection limits were 0.01-0.045 ng/mL, and the linearity was from 0.5 ng/mL to 96 ng/mL. The R.S.D.s of repeatability for retention time and peak area were all within 0.074% and 6.7%, respectively. The recoveries of the PAHs were 78-127% from the samples taken from river water.

关键词： Sorptive extraction PDMS-coated microspheres Sol-gel PAHs

Phase behavior of binary system of bromobenzene-chlorobenzene confined in SBA-15 and MCM-41

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Chinese Chemical Letters 2011年第12期22卷 1497-1500页

作者： xiao zheng Lan Hai Rong Pei Chuan Xian Cheng College of Chemistry and Materials Science Shandong Agriculture University Taian 271018 China

Phase behavior of binary system of bromobenzene-chlorobenzene （C6H5Br-C6H5Cl） confined in SBA-15 and MCM-41 （pore diameter 8 nm, 3.8 nm, respectively） has been investigated by means of differential scanning calorimetry （DSC）. Phase diagram of C6H5Br-C6H5Cl system confined in SBA-15 is a type of the complete miscible both in liquid and solid state, the same phase behavior as the bulk system. However, the phase diagram comprises only one boundary line, which is shifted down 22-36 K with respect to the bulk system. C6H5Br-C6H5Cl or the mixture within nanopores of MCM-41 is nonfreezing. The different phase behavior of the system confined in SBA-15 and MCM-41 is thought mainly due to the relative size of pore to molecule. （C） 2011 xiao zheng Lan. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Phase behavior Confinement SBA-15 MCM-41 Phase diagram

Effect of time interval on microstructure evolution of medium carbon steel during warm deformation

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Journal of Iron and Steel Research International 2019年第6期26卷 602-610页

作者： Hong-bin Li xiao-ping zheng De-cheng Wan Lian-sheng Chen College of Metallurgy and Energy North China University of Science and Technology Tangshan 063009 Hebei China Modem Metallurgy of Hebei Province Key Laboratory Tangshan 063009 Hebei China

The thermal mechanical simulator system (Gleeble-3500) was used to carry out the double passes compression tests. The microstructure evolution of medium carbon steel with different time intervals during warm deformation was investigated by scanning electron microscopy, transmission electron microscopy and electron back-scattered diffraction. The results show that the effects of time interval on microstructure evolution are very important. The low-angle boundaries transform into high-angle boundaries (HABs) during interval. The fraction of HABs and homogeneity of particle carbides increase with increasing time interval. In addition, the homogeneity of carbides also increases with the strain. However, the effects of time interval on the microstructure evolution are negligible when it exceeds 100 s.

关键词： Double-pass deformation Warm deformation Microstructure evolution Misorientation

Influence of α-Al_2O_3 and AlF_3 on pyrohydrolysis of Li_3AlF_6

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Nuclear Science and Techniques 2018年第9期29卷 148-156页

作者： Jia Peng xiao-Bei zheng Yu-Xia Liu Lan Zhang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China CAS Innovative Academy in TMSR Energy System Shanghai 201800China

In this study, Li_3AlF_6 was employed to simulate the molten salt LiF–BeF_2 to explore its pyrohydrolysis behavior and that of its components, i.e., LiF and AlF_3,respectively. The influence of the accelerators α-Al_2O_3 and AlF_3 on the pyrohydrolysis of LiF and Li_3AlF_6 was investigated. Finally, the solid pyrohydrolytic products were characterized by means of X-ray diffraction, and the corresponding reaction mechanisms were proposed. These experimental results indicated that AlF_3 was completely hydrolyzed to the corresponding oxide α-Al_2O_3 at 650 ℃ in 1 h, whereas the complete hydrolysis of LiF and Li_3AlF_6 required the assistance of either α-Al_2O_3 or AlF_3 under the same conditions. The influence of the accelerator α-Al_2O_3 and AlF_3 on the pyrohydrolytic behavior of Li_3AlF_6 provides references for future research studies on the pyrohydrolysis of LiF–BeF_2 and multi-component molten salts.

关键词： Pyrohydrolysis Accelerator Li3AlF6 molten salt Reaction mechanism