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Influence of pressure disturbance wave on dynamic response characteristics of liquid film seal for multiphase pump

Petroleum Science 2024年第3期21卷 2048-2065页

作者： Qing-Ping Li Jin-Ya zhang Jia-Xiang zhang yong-xue zhang CNOOC Research Institute Company Limited Beijing100028China State Key Laboratory of Natural Gas Hydrate Beijing100028China College of Mechanical and Transportation Engineering China University of PetroleumBeijing2249China

Slug flow or high GVF(Gas Volume Fraction)conditions can cause pressure disturbance waves and alternating loads at the boundary of mechanical seals for multiphase pumps,endangering the safety of multiphase pump *** mechanical seal model is simplified by using periodic boundary conditions and numerical calculations are carried out based on the Zwart-Gerber-Belamri cavitation ***(User Define Function)programs such as structural dynamics equations,alternating load equations,and pressure disturbance equations are embedded in numerical calculations,and the dynamic response characteristics of mechanical seal are studied using layered dynamic mesh *** results show that when the pressure disturbance occurs at the inlet,as the amplitude and period of the disturbance increase,the film thickness gradually *** the fundamental reason for the hysteresis of the film thickness change is that the pressure in the high-pressure area cannot be restored in a timely *** maximum value of leakage and the minimum value of axial velocity are independent of the disturbance period and determined by the disturbance *** mutual interference between enhanced waves does not have a significant impact on the film thickness,while the front wave in the attenuated wave has a promoting effect on the subsequent film thickness changes,and the fluctuation of the liquid film cavitation rate and axial velocity under the attenuated wave condition deviates from the initial *** with pressure disturbance conditions,alternating load conditions have a more significant impact on film thickness and *** actual operation,it is necessary to avoid alternating load conditions in multiphase pump mechanical seals.

关键词： Multiphase pump Liquid film seal Pressure disturbance wave Dynamic response characteristics

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Isolation and Molecular Characterization of High Molecular Weight Glutenin Subunit Genes 1Bx13 and 1By16 from Hexaploid Wheat

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Journal of Integrative Plant Biology 2008年第3期50卷 329-337页

作者： Bin-Shuang Pang xue-yong zhang Key Laboratory of Crop Germplasm and Biotechnology Ministry of Agriculture Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing 100081 China

The high molecular weight glutenin subunit （HMW-GS） pair 1Bx13＋1By16 are recognized to positively correlate with bread-making quality; however, their molecular data remain unknown. In order to reveal the mechanism by which 1By16 and 1Bx13 creates high quality, their open reading frames （ORFs） were amplified from common wheat Atlas66 and Jimai 20 using primers that were designed based on published sequences of HMW glutenin genes. The ORF of 1By16 was 2220bp, deduced into 738 amino acid residues with seven cysteines including 59 hexapeptides and 22 nanopeptides motifs. The ORF of 1Bx13 was 2385bp, deduced into 795 amino acid residues with four cysteines including 68 hexapeptides, 25 nanopeptides and six tripepUdes motifs. We found that 1By16 was the largest y-type HMW glutenin gene described to date in common wheat. The 1By16 had 36 amino acid residues inserted in the central repetitive domain compared with 1By15. Expression in bacteria and western-blot tests confirmed that the sequence cloned was the ORF of HMW-GS 1By16, and that 1Bx13 was one of the largest 1Bx genes that have been described so far in common wheat, exhibiting a hexapeptide （PGQGQQ） insertion in the end of central repetitive domain compared with 1Bx7. A phylogenetic tree based on the deduced full-length amino acid sequence alignment of the published HMW-GS genes showed that the 1By16 was clustered with Glu-1B-2, and that the 1Bx13 was clustered with Glu-1B-1 alleles.

关键词： bacterial expression high molecular weight glutenin subunit 1Bx13 1By16 western-blot wheat.

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Numerical investigation of the interactions between a laser-generated bubble and a particle near a solid wall

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Journal of Hydrodynamics 2021年第2期33卷 311-322页

作者： Jian-yong Yin yong-xue zhang Jian-jun Zhu Liang Lü Shi-da Li College of Mechanical and Transportation Engineering China University of Petroleum-BeijingBeijing 102249China Beijing Key Laboratory of Process Fluid Filtration and Separation China University of Petroleum-BeijingBeijing 102249China School of International Education Hainan Medical UniversityHaikou 571199China Department of Thermal Engineering Chengde Petroleum CollegeChengde 067000China

The interactions between the bubbles and the particles near structures are important issues for the applications of the cavitation in the fluid *** study the hidden microscopic mechanisms,a numerical method for simulating the laser-generated bubble between the solid wall and a particle is developed in this paper with considerations of the viscosities and the compressibility of the gas and the liquid phases,as well as the surface tension between *** gas-liquid interface is tracked by the coupling level set and the volume of fluid(CLSVOF)*** numerical results clearly reveal that the particle can influence the cavitation bubble *** potential damage of the nearby structures is numerically quantified in terms of the wall pressure,which helps better understand the synergetic effects of the particle on the *** effects of three dimensionless parameters on the wall pressure are also investigated,especially,on the peak pressure,namely,γ1(defined as L_(1)/R_(max),where L_(1)is the distance from the center of the initial bubble to the solid wall and R_(max)is the maximum bubble radius),γ_(2)(defined as L_(2)/R_(max),where L_(2)is the distance from the lower surface of the spherical particle to the initial bubble center)andθ(defined as Rp/R_(max),where Rp is the spherical particle radius).Further numerical results show that these parameters play a dominant role in determining the peak *** y_(1)1.00,the peak pressure is caused by the shock *** the increase ofθor decrease ofγ_(2),the peak pressure ***γ_(2)>2.00,the effect of the particle on the bubble behavior can be neglected.

关键词： Cavitation bubble spherical particle coupling level set and the volume of fluid(CLSVOF) solid wall OpenFOAM

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Identification and Preliminary Analysis of Several Centromere-associated Bacterial Artificial Chromosome Clones from a Diploid Wheat Library

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Journal of Integrative Plant Biology 2006年第3期48卷 348-358页

作者： Zhao Liu Wei Yue Yu-Shen Dong xue-yong zhang Key Laboratory of Crop Germplasm and Biotechnology Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing 100081 China State Key Laboratory of Crop Genetics and Germplasm Enhancement Nanjing Agricultural University Nanjing 210095 China

Although the centromeres of some plants have been investlgated prevlously, our knowledge of the wheat centromere Is still very llmlted. To understand the structure and functlon of the wheat centromere, we used two centromeric repeats （RCS1 and CCS1-5ab） to obtain some centromere-assoclated bacterial artificial chromosome （BAC） clones in 32 RCS1-related BAC clones that had been screened out from a diploid wheat （Triticum boeoticum Boiss.; 2n=2x=14） BAC library. Southern hybridization results indicated that, of the 32 candidates, there were 28 RCS1-positive clones. Based on gel blot patterns, the frequency of RCS1 was approximately one copy every 69.4 kb in these 28 RCS1-positive BAC clones. More bands were detected when the same filter was probed with CCS1-5ab. Furthermore, the CCS1 bands covered all the bands detected by RCS1, which suggests that some CCS1 repeats were distributed together with RCS1. The frequency of CCS1 families was once every 35.8 kb, nearly twice that of RCS1. Fluorescence in situ hybridization （FISH） analysis Indicated that the five BAC clones containing RCS1 and CCS1 sequences all detected signals at the centromerlc regions in hexaplold wheat, but the signal intensities on the A-genome chromosomes were stronger than those on the B- and/or Dgenome chromosomes. The FISH analysis among nine Triticeae cereals indicated that there were A-genomespecific （or rich） sequences dispersing on chromosome arms in the BAC clone TbBACS. In addition, at the interphase cells, the centromeres of diploid species usually clustered at one pole and formed a ring-like allocation In the period before metaphase.

关键词： centromere fluorescence in situ hybridization (FISH) repeat Southern hybridization Triticum boeoticum.

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High-speed experimental photography of collapsing cavitation bubble between a spherical particle and a rigid wall

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Journal of Hydrodynamics 2018年第6期30卷 1012-1021页

作者： Yu-ning zhang Xiao-yang Xie Yu-ning zhang yong-xue zhang College of Mechanical and Transportation Engineering China University of Petroleum-Beijing Beijing 102249 China Beijing Key Laboratory of Process Fluid Filtration and Separation China University of Petroleum-BeijingBeijing 102249 China Key Laboratory of Condition Monitoring and Control for Power Plant Equipment (Ministry of Education) School of Energy Power and Mechanical Engineering North China Electric Power University Beijing 102206 China School of Nuclear Science and Engineering North China Electric Power University Beijing 102206 China

The synergetic effects between cavitation bubbles and silt particles on the damages of materials are essential problems in fluid machineries. For studying the underlying microscopic mechanisms, in the present paper, the dynamic behaviors of a single cavitation bubble between a spherical particle and a rigid wall are experimentally investigated with a high-speed camera. The results indicate that the existence of the particle can affect the bubble shape during collapse and significantly accelerate the collapse velocity of the bubble. The influences of the particle size, the distance between the bubble and the particle and the distance between the bubble and the rigid wall on the phenomena are qualitatively and quantitatively analyzed. These parameters can prominently affect the collapse velocity of the bubble(especially its maximum value).

关键词： Cavitation particle bubble dynamics bubble collapse

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Promotion on the differentiation of retinal Müller cells into retinal ganglion cells by Brn-3b

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International Journal of Ophthalmology(English edition) 2016年第7期9卷 948-954页

作者： Zhen-Kai Wu Lan Cao xue-yong zhang Wei-Tao Song Xiao-Bo Xia Department of Ophthalmology Xiangya HospitalCentral South UniversityChangsha 410008 Hunan ProvinceChina

AIM： To investigate the role of Brn-3b in differentiation process of stem cells derived from retinal Muller cells into the ganglion cell. METHODS： The passage culture method of Muller cells from retina of newborn Sprague Dawley rats was carried out by repeated incomplete pancreatic enzyme digestion method. The cells were detected by fluorescence- activated ceil sorter （FACS）, immunohistochemistry technology and reverse transcription-polymerase chain reaction （RT-PCR） to determine the purity. The third passage of cells was induced in the serum-free dedifferentiation medium. The expression of the specific markers Ki-67 and nestin of retinal stem cells was measured by RT-PCR and Western blot. The cell proliferation of retinal stem cells was detected by 5- Ethynyl-2＇-deoxyuridine （Edu） staining. The cells were randomly divided into 5 groups as follows： group A： Brn-3bsiRNA group; group B： Brn-3b control siRNA group; group C： pGC-Brn-3b-green fluorescent protein （GFP） group; group D： pGC-GFP group; group E： control group （without any handling）. The purified Muller cells were cultured for 3-7d, then, the percentage of ganglion cells was counted by immunofluorescence staining. RESULTS： FACS demonstrated the purity of retinal Muller cells was more 97.44%. A few spherical cell spheres appeared. Immunofluorescence staining showed that stem cells within the spheres were positive for retinal stem cell-specific markers nestin （red fluorescence, 92.94%±6.48%） and Ki-67 （green fluorescence, 85.96%± 6.04% ）. Meanwhile, RT-PCR analysis showed cell spheres in the culture to have expressed a battery of transcripts characteristic of stem cells such as nestin and Ki-67, which were absent in the Muller cells. Western blot analysis further confirmed the expression of nestin and Ki-67 in the cell spheres but not in the Muller cells. Edu staining showed most of the nuclei within the cell spheres were stained red （82.80%±6.65%）, suggesting the new cell spheres had the capacity for effectiv

关键词： Mtiller cells retinal ganglion cells Brn-3b stem cells differentiation

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Integration of urchin-like MnCo_(2)O_(4)@C core–shell nanowire arrays within porous copper current collector for superior performance Li-ion battery anodes

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Rare Metals 2024年第2期43卷 599-611页

作者： xue-Ru zhang Qiong Wu yong zhang Xi-Fei Li Ting Xie Yu-Cheng Wu Instrumental Analysis Center Hefei University of TechnologyHefei230009China Key Laboratory of Advanced Functional Materials and Devices of Anhui Province Hefei230009China School of Materials Science and Engineering Hefei University of TechnologyHefei230009China Institute of Advanced Electrochemical Energy Xi’an University of TechnologyXi’an710048China

Spinel MnCo_(2)O_(4) is a promising energy storage candidate as anode materials in lithium-ion batteries owing to synergistic effects of two intrinsic solid-state redox ***,low conductivity,poor rate capacity and rapid capacity fading have seriously impaired its practical *** overcome the inferiorities,urchin-like MnCo_(2)O_(4)@C core–shell nanowire arrays have been fabricated directly within a porous copper current collector via a facile hydrothermal method followed by a chemical vapor deposition carbonization *** a typical nanowire,the core is composed of interconnected MnCo_(2)O_(4)nanoparticles and the shell shows as a thin amorphous carbon *** integrated MnCo_(2)O_(4)@C/Cu structure could act as working anodes without using additives or polymer *** MnCo_(2)O_(4)@C/Cu possesses slightly longer Li-ion insertion/desertion pathway than that of MnCo_(2)O_(4)/Cu,the carbon shell could effectively prevent the pulverization of MnCo_(2)O_(4) and lower down charge transfer resistance and actively participate in Li-ion *** rearrangement of carbon atoms during lithiation/delithiation cycling could inhibit the formation of passive solid electrolyte interphase *** a result,the MnCo_(2)O_(4)@C/Cu electrode presents superior rate capacity(600 mAh·g^(−1) at 1 A·g^(−1)) and better stability(797 mAh·g^(−1) after 200 cycles at 100 mA·g^(−1)).The excellent reversible Li ion storage capacity,cycling stability and rate capacity endow MnCo_(2)O_(4)@C/Cu great potential as stable and high output integrated anode materials in Li-ion batteries.

关键词： MnCo_(2)O_(4)@C Urchin-like nanowire arrays Core-shell Integrated anode materials Lithium-ion batteries

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Antisense telomerase RNA induced human gastric cancer cell apoptosis

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World Journal of Gastroenterology 2000年第3期6卷 430-432页

作者： Fang Xin zhang xue yong zhang Dai Ming Fan Zi Yun Deng Yan Yan Han Ping Wu Jun Jie Fan Department of Gastroenterology Lanzhou PLA General HospitalLanzhou 730050Gansu ProvinceChina Institute of Digestive Diseases the Fourth Military Medical UniversityXi’an 710033Shaanxi ProvinceChina

INTRODUCTION Human tissue homeostasis is precisely regulated bycellular division,differentiation and *** somatic cells progressively lose telomererestriction fragment(TRF)length with eachsuccessive cell division,eventually leading tocellular quiescence,chromosomal end-degradationand *** the contrary,stabilization oftelomere lengths by expressing telomerase,an RNA-dependent DNA polymerase,may be involved incellular immortality and carcinogenesis.

关键词： stomach neoplasms RNA antisense telomere gene therapy

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Comparison of two methods used to culture and purify rat retinal Mller cells

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International Journal of Ophthalmology(English edition) 2013年第6期6卷 778-784页

作者： Wei-Tao Song xue-yong zhang Si-Qi Xiong Dan Wen Jian Jiang Xiao-Bo Xia Department of Ophthalmology Xiangya HospitalCentral South University

AIM:To study two methods for culturing and purifying Sprague-Dawley(SD)rat retinal Muller cells and determine which one is ***:The passage culture method of Muller cells was respectively carried out by complete pancreatic enzyme digestion method and repeated incomplete pancreatic enzyme digestion *** culturing retinal cells for one month through these two methods,fluorescence-activated cell sorter(FACS),RT-PCR,and immunohistochemistry technology were performed to examine the enrichment and purity of Muller glial cells,and carried out two-sample approximate t test using SSPS 13.0 to further compare the Muller cell positive rate in both ***:The statistical results showed that the purity of Muller cells was 83.2%±5.16%in group A,and the purity was 98.5%±1.08%in group *** two-sample approximate t test analysis demonstrated that the difference between group A and group B was statistically significant(t=-9.178,P<0.005).The results clearly exhibited a difference between the purity of Muller cells cultured by the complete pancreatic enzyme digestion method(group A)and the repeated incomplete pancreatic enzyme digestion method(group B).CONCLUSION:Compared with the complete pancreatic enzyme digestion method,this novel method was more efficient and a higher purity of Muller cells could be obtained using this approach.

关键词： primary culture passage purification retinal Mller cell trypsinization

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Analyses on the misdiagnoses of 25 patients with unilateral optic nerve sheath meningioma

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International Journal of Ophthalmology(English edition) 2016年第9期9卷 1315-1319页

作者： Jun-Feng Mao Xiao-Bo Xia Xiang-Bo Tang xue-yong zhang Dan Wen Department of Ophthalmology Xiangya HospitalCentral South University

AIM：To investigate clinical features of optic nerve sheath meningioma（ONSM） that was misdiagnosed,and to find methods to reduce the ***：Retrospective series ***-five misdisgnosed patients with unilateral ONSM were collected from Jan.2008 to Jan.2015 and the clinical records ***：Patients were misdiagnosed with acute papillitis most frequently（P=17）,immediately followed by optic atrophy（P=8）,ischemic optic neuropathy（P=5）,acute retrobulbar optic neuritis（P=5）,optic disc vasculitis（P =3）.For each patient,the minimum frequency of misdiagnoses was once and the maximum was 4 *** for the lasting time of being misdiagnosed,the shortest was 1.5mo and the longest was 45 *** cases（84%） were once treated with glucocorticoids,and its side effects was found in seventeen *** patients（80%） complained with varying degree of vision *** a definite diagnosis was made,sixteen cases（64%） showed slight exophthalmos and eighteen cases（72%） had the tubular ***：ONSM without loss obvious exophthalmos is easily misdiagnosed in clinic,and for most of these ONSMs are tubular.

关键词： optic nerve sheath meningioma misdiagnosis clinical feature

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