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Recurrent coronal jets observed by SDO/AIA

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Research in Astronomy and Astrophysics 2021年第10期21卷 213-220页

作者： Yan-jie zhang Qing-Min zhang jun Dai Zhe Xu Hai-Sheng ji Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryCASNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China

In this paper,we carried out multiwavelength observations of three recurring jets on 2014November *** jets originated from the same region at the edge of AR 12205 and propagated along the same coronal *** eruptions were generated by magnetic reconnection,which is evidenced by continuous magnetic cancellation at the jet *** projected initial velocity of jet2 is~402 km s^(-1).The accelerations in the ascending and descending phases of jet2 are not consistent,the former is considerably larger than the value of g_(⊙) at the solar surface,while the latter is lower than g_(⊙).There are two possible candidates of extra forces acting on jet2 during its *** is the downward gas pressure from jet1when it falls back and meets with *** other is the viscous drag from the surrounding plasma during the fast propagation of *** a contrast,the accelerations of jet3 in the rising and falling phases are constant,implying that the propagation of jet3 is not significantly influenced by extra forces.

关键词： Sun:corona Sun:activity Sun:magnetic fields

Modeling of high-temperature reforming reactor based on interactive thermal control with a tail gas combustor

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Advances in Manufacturing 2016年第1期4卷 47-54页

作者： Dan zhang Zhong Shao ji-Ping Xin Ai-jun Li Shanghai Key Laboratory of Mechanics in EnergyEngineering Institute of Applied Mathematics andMechanics Shanghai University Shanghai 200444People's Republic of China Research Center of Composite Materials ShanghaiUniversity Shanghai 200444 People's Republic of China

This paper proposes a method to model hydrocarbon reforming by coupling detailed chemical kinetics with complex computational fluid dynamics. The entire chemistry of catalyzed reactions was confined within the geometrically simple channels and modeled using the low-dimensional plug model, into which the interactive thermal control of the multi-channel reforming reactor has been implemented with a tail-gas combustor around the external surface of these catalytic channels. The geomet- rically complex flow in the tail gas combustor was simu- lated using FLUENT without involving any chemical reactions. The influences of the conditions at the reactor inlet such as the inlet gas velocity, the inlet gas composi- tion and the variety of hydrocarbons of each channel on gas conversions were investigated numerically. The impact of the tail gas combustor setup on the efficiency of the reforming reactor was also analyzed. Methane catalytic partial oxidation （CPOx） and propane steam reforming （SR） were used to illustrate the approach reported in the present work.

关键词： Computational fluid dynamics Reactionkinetics Catalytic partial oxidation Steam reforming

High-entropy pyrochlores with low thermal conductivity for thermal barrier coating materials

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Journal of Advanced Ceramics 2019年第4期8卷 576-582页

作者： Fei LI Lin ZHOU ji-Xuan LIU Yongcheng LIANG Guo-jun zhang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and Engineering Institute of Functional Materials College of ScienceDonghua University

High-entropy pyrochlore-type structures based on rare-earth zirconates are successfully produced by conventional solid-state reaction method. Six rare-earth oxides(La2O3, Nd2O3, Sm2O3, Eu2O3, Gd2O3, and Y2O3) and ZrO2 are used as the raw powders. Five out of the six rare-earth oxides with equimolar ratio and ZrO2 are mixed and sintered at different temperatures for investigating the reaction process. The results demonstrate that the high-entropy pyrochlores(5RE1/5)2 Zr2O7 have been formed after heated at 1000 ℃. The(5RE1/5)2Zr2O7 are highly sintering resistant and possess excellent thermal stability. The thermal conductivities of the(5RE1/5)2Zr2O7 high-entropy ceramics are below 1 W·m–1·K–1 in the temperature range of 300–1200 ℃. The(5RE1/5)2Zr2O7 can be potential thermal barrier coating materials.

关键词： thermal barrier coating(TBC) pyrochlore high-entropy ceramics thermal conductivity

Experimental research on charging characteristics of a pressure-controlled VRLA battery in high-temperature environments

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第3期10卷 418-422页

作者： Hua ZHU jin-jun TAN zhang-lu XU ji-sen XU Institute of Thermal Science and Power Systems Zhejiang University Hangzhou 310027 China

Valve-regulated-lead-acid (VRLA) battery charging performed in high-temperature environments is extremely risky under overcharge conditions, and may lead to a subsequent thermal runaway. A new pressure-controlled charging method was adopted and the charging characteristics of the pressure-controlled VRLA battery in high-temperature environments were ex-perimentally studied. The concept was tested in a large temperature gradient to obtain more details about the effects of users' accustomed charging and discharging modes on battery capacity. The premature capacity loss (PCL) phenomenon under high temperature exposure was analyzed. The results showed that the capacity loss could be recovered by charging using a large current.

关键词： Valve-regulated-lead-acid (VRLA) battery Pressure-controlled charging method High-temperature environments Charging and discharging characteristics

Overexpression of a maize SNF-related protein kinase gene, ZmSnRK2.11, reduces salt and drought tolerance in Arabidopsis

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Journal of Integrative Agriculture 2015年第7期14卷 1229-1241页

作者： zhang Fan CHEN Xun-ji WANG jian-hua ZHENG jun College of Agriculture and Biotechnology China Agricultural University Institute of Crop Science Chinese Academy of Agricultural Sciences Institute of Nuclear Technology and Biotechnology Xinjiang Academy of Agricultural Sciences

Sucrose non-fermenting-1 related protein kinase 2 （SnRK2） is a unique family of protein kinases associated with abiotic stress signal transduction in plants. In this study, a maize SnRK2 gene ZmSnRK2.11 was cloned and characterized. The results showed that ZmSnRK2.11 is up-regulated by high-salinity and dehydration treatment, and it is expressed mainly in maize mature leaf. Atransient expression assay using onion epidermal cells revealed that ZmSnRK2.11-GFP fusion proteins are localized to both the nucleus and cytoplasm. Overexpressing-ZmSnRK2.11 in Arabidopsis resulted in salt and drought sensitivity phenotypes that exhibited an increased rate of water loss, reduced relative water content, delayed stoma closure, accumulated less free proline content and increased malondialdehyde （MDA） content relative to the phenotypes observed in wild-type （WT） control. Furthermore, overexpression of ZmSnRK2.11 up-regulated the expression of the genes ABI1 and ABI2 and decreased the expression of DREB2A and P5CSI. Taken together, our results suggest that ZmSnRK2.11 is a possible negative regulator involved in the salt and drought stress signal transduction pathways in plants.

关键词： maize salt and drought stresses ZmSnRK2.11 SnRK2

Identification of QTLs Conferring Agronomic and Quality Traits in Hexaploid Wheat

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Journal of Integrative Agriculture 2012年第9期11卷 1399-1408页

作者： MAjun zhang Cai-ying YAN Gui-jun LILT Chun-ji CSIRO Plant Industry St Lucia QLD 4067 Australia Key Laboratory for Crop Germplasm Resources of Hebei Province~College of Life Science Agricultural University of Hebei Baoding 071001 P.R.China School of Plant Biology The University of Western Australia Perth WA 6009 Australia

The availability of elite germplasm resources with high yield and quality potentials is very important for development of cultivars in wheat. Thus, seeking such resources has been the continuous effort of breeder community. In this study, genetic analysis of a novel resource, Triticum spelta line CSCR6, from Australia was made by use of a recombination inbred line （RIL） population of 82 individuals from the cross between CSCR6 and another Australian hexaploid wheat cultivar, Lang. Data of a multiple environmental test was employed to genetically dissect quantitative trait loci （QTL） for agronomic traits such as plant height （PH）, spike length （SL）, spikelet per spike （SPI）, grain number per spike （GNS） and thousand grains weight （TGW） and for quality traits including grain protein content （GPC）, gluten content （GC）, grain hardness （GH）, falling number （FN） and sedimentation value （SV）. A 24 QTLs with additive effects were detected for all the investigated traits, and were located on chromosomes 1B, 1D, 2B, 3A, 3B, 3D, 4B, 5A, 5B, 7A, and 7B, respectively. Some QTLs located on 2B and 4B showed higher explanation of phenotypic variances and were not obviously interacted with environment. A QTL in the marker interval of wPT-5334-wPT-4918 （near the locus barc 0199） on 4B gave the highest contribution ratio of 30.76% on PH, while Qgpc-4B and Qgc-4B gave 13.07 and 14.70% contribution ratio on GPC and GC, respectively. Qph-2B, Qgns-2B, and Qgpc-2B showed 13.36, 10.00, and 10.79% contribution ratio on PH, GNS and GPC, respectively. Also, a QTL on 5A, Qsl- 5A, could explain 25.12% of phenotypic variance on SL. For most of agronomic and quality traits, CSCR6 alleles produced increase effects. The fact that a number of loci affecting the investigated traits were detected in T. spelta line CSCR6 revealed that it could offer a new opportunity for the manipulation of these traits in wheat breeding programs.

关键词： wheat QTL analysis RILs agronomic traits quality traits

Theoretical Analysis and Experimental Verification on Valve-less Piezoelectric Pump with Hemisphere-segment Bluff-body

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Chinese Journal of Mechanical Engineering 2014年第3期27卷 595-605页

作者： ji jing zhang jianhui XIA Qixiao WANG Shouyin HUANG jun ZHAO Chunsheng State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics College of Mechanical and Electrical Engineering Qingdao Agricultural University College of Mechanical and Electronic Engineer Beijing Union University Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences

Existing researches on no-moving part valves in valve-less piezoelectric pumps mainly concentrate on pipeline valves and chamber bottom valves, which leads to the complex structure and manufacturing process of pump channel and chamber bottom. Furthermore, position fixed valves with respect to the inlet and outlet also makes the adjustability and controllability of flow rate worse. In order to overcome these shortcomings, this paper puts forward a novel implantable structure of valve-less piezoelectric pump with hemisphere-segments in the pump chamber. Based on the theory of flow around bluff-body, the flow resistance on the spherical and round surface of hemisphere-segment is different when fluid flows through, and the macroscopic flow resistance differences thus formed are also different. A novel valve-less piezoelectric pump with hemisphere-segment bluff-body （HSBB） is presented and designed. HSBB is the no-moving part valve. By the method of volume and momentum comparison, the stress on the bluff-body in the pump chamber is analyzed. The essential reason of unidirectional fluid pumping is expounded, and the flow rate formula is obtained. To verify the theory, a prototype is produced. By using the prototype, experimental research on the relationship between flow rate, pressure difference, voltage, and frequency has been carried out, which proves the correctness of the above theory. This prototype has six hemisphere-segments in the chamber filled with water, and the effective diameter of the piezoelectric bimorph is 30mm. The experiment result shows that the flow rate can reach 0.50 mL/s at the frequency of 6 Hz and the voltage of 110 V. Besides, the pressure difference can reach 26.2 mm H20 at the frequency of 6 Hz and the voltage of 160 V. This research proposes a valve-less piezoelectric pump with hemisphere-segment bluff-body, and its validity and feasibility is verified through theoretical analysis and experiment.

关键词： valve-less piezoelectric pump hemisphere-segment bluff-body flow resistance

Alteration of the esophageal microbiota in Barrett's esophagus and esophageal adenocarcinoma

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World Journal of Gastroenterology 2019年第18期25卷 2149-2161页

作者： jing Lv Lei Guo ji-jun Liu He-Ping Zhao jun zhang ji-Han Wang Department of Clinical Laboratory Honghui HospitalXi'an Jiaotong University Department of Spinal Surgery Honghui Hospital Xi'an Jiaotong University Department of Gastroenterology Second Affiliated Hospital of Xi’an Jiaotong University

The incidence of esophageal adenocarcinoma(EAC) has increased in recent decades, and its 5-year survival rate is less than 20%. As a well-established precursor, patients with Barrett's esophagus(BE) have a persistent risk of progression to EAC. Many researchers have already identified some factors that may contribute to the development of BE and EAC, and the identified risks include gastroesophageal reflux(GER), male sex, older age, central obesity,tobacco smoking, Helicobacter pylori(H. pylori) eradication, and the administration of proton pump inhibitors(PPIs) and antibiotics. The human gut harbors trillions of microorganisms, the majority of which are bacteria. These microorganisms benefit the human host in many ways, such as helping in digestion, assisting in the synthesis of certain vitamins, promoting the development of the gastrointestinal immune system, regulating metabolism and preventing invasion by specific pathogens. In contrast, microbial dysbiosis may play important roles in various diseases, such as inflammation and cancers. The composition of the microbiota located in the normal esophagus is relatively conserved without distinct microbial preferences in the upper, middle and lower esophagus. Six major phyla constitute the esophageal microbiota, including Firmicutes,Bacteroides, Actinobacteria, Proteobacteria, Fusobacteria and TM7, similar to the oral microbiota. Streptococcus dominates the esophageal microbiota. However, the microbiota varies in different esophageal diseases compared to that in the healthy esophagus. The type Ⅰ microbiota, which is primarily composed of gram-positive bacteria, is closely associated with the normal esophagus, while type Ⅱ microbiota has enriched gram-negative bacteria and is mainly associated with the abnormal esophagus. These increased gram-negative anaerobes/microaerophiles include Veillonella, Prevotella, Haemophilus, Neisseria, Granulicatella and Fusobacterium, many of which are associated with BE. The microbial d

关键词： Barrett's esophagus esophageal adenocarcinoma microorganisms esophageal microbiota alteration dysbiosis

Third-Order Stokes Wave Solutions of the Free Surface Capillary- Gravity Wave and the Interfacial Internal Wave

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China Ocean Engineering 2017年第6期31卷 781-787页

作者： MENG Rui-jun CUI ji-feng CHEN Xiao-gang zhang Bao-le zhang Hong-bo College of Science Inner Mongolia University of Technology Hohhot 010051 China

Based on the Stokes wave theory, the capillary-gravity wave and the interfacial internal wave in two-layer constant depth＇s fluid system are investigated. The fluids are assumed to be incompressible, inviscid and irrotational. The third-order Stokes wave solutions are given by using a perturbation method. The results indicate that the third-order solutions depend on the surface tension, the density and the depth of each layer. As expected, the first-order solutions are the linear theoretical results （the small amplitude wave theoretical results）. The second-order and the third-order solutions describe the nonlinear modification and the nonlinear interactions. The nonlinear impact appears not only in the n （n〉~2） times＇ high frequency components, but also in the low frequency components. It is also noted that the wave velocity depends on the wave number, depth, wave amplitude and surface tension.

关键词： surface tension capillary-gravity waves Stokes wave theory third-order Stokes wave solutions