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| 1 | Oral immunization of animals with transgenic cherry tomatillo expressing HBsAg显示文摘AIM: To investigate the expression of recombinant HBsAg (rHBsAg) in transgenic cherry tomatillo in order to explore the feasibility of producing HBV oral vaccine with cherry tomatillo by animal immune tests.METHODS: The recombinant plant expression vector containing HBsAg gene was constructed. Mediated with Agrobacterium tumefaciens, HBsAg gene was transferred into cotyledons of cherry tomatillo. Transformed cherry tomatillos were obtained through hygromycin delay-selection. Integrated DNA in transgenic cherry tomatillo was confirmed by hygromycin resistance selection, Gus detection, polymerase chain reaction (PCR) and dot blotting analysis. Antigenicity of rHBsAg was examined by ELISA and the immunogenicity of rHBsAg derived from transgenic cherry tomatillo tissues was confirmed by oral feed of transformed tissues to BALB/c mice primed with commercial HBV vaccines. Specific antibody titers in mice's serum were examined by ELISA every week.RESULTS: By far, 10 positive lines of transgenic cherry tomatillos containing HBsAg gene were obtained. Among different organs of the same transgenic cherry tomatillo,level of rHBsAg expressed in leaves was the highest with the yield up to 300ng/g fresh weight. And the rHBsAg expression level in fruits was about 10 ng/g fresh weight.In animal immune tests, oral delivery with transgenic tissues to mice primed with commercial vaccine instead of naive mice resulted in significant immune response.CONCLUSION: The result of this animal immune test indicated the rHBsAg derived from transgenic cherry tomatillo possessed normal immunogenicity. This work demonstrated the feasibility to generate oral immunogenic rHBsAg in transgenic cherry tomatillo, and would provide some experimental approach for the production of low-cost oral vaccines using transgenic cherry tomatillo in large scale. | YiGao YingMa MeiLi TongCheng Shao-WeiLi JunZhan Ning-ShaoXia | 2003 | World Journal of Gastroenterology2003，9，5： | 23 |
| 2 | Computational fluid dynamics evaluation of the effect of different city designs on the wind environment of a downwind natural heritage site显示文摘Disturbance in wind regime and sand erosion deposition balance may lead to burial and eventual vanishing of a site.This study conducted 3D computational fluid dynamics(CFD)simulations to evaluate the effect of a proposed city design on the wind environment of the Crescent Spring,a downwind natural heritage site located in Dunhuang,Northwestern China.Satellite terrain data from the Advanced Spaceborne Thermal Emission and Reflection Radiometer(ASTER)Digital Elevation Model(DEM)were used to construct the solid surface model.Steady-state Reynolds Averaged Navier-Stokes equations(RANS)with shear stress transport(SST)k-ωturbulence model were then applied to solve the flow field problems.Land-use changes were modeled implicitly by dividing the underlying surface into different areas and by applying corresponding aerodynamic roughness lengths.Simulations were performed by using cases with different city areas and building heights.Results show that the selected model could capture the surface roughness changes and could adjust wind profile over a large area.Wind profiles varied over the greenfield to the north and over the Gobi land to the east of the spring.Therefore,different wind speed reduction effects were observed from various city construction scenarios.The current city design would lead to about 2 m/s of wind speed reduction at the downwind city edge and about 1 m/s of wind speed reduction at the north of the spring at 35-m height.Reducing the city height in the north greenfield area could efficiently eliminate the negative effects of wind spee.By contrast,restricting the city area worked better in the eastern Gobi area compared with other parts of the study area.Wind speed reduction in areas near the spring could be limited to 0.1 m/s by combining these two abatement strategies.The CFD method could be applied to simulate the wind environment affected by other land-use changes over a large terrain. | BenLi LIU JianJun QU QingHe NIU JunZhan WANG KeCun ZHANG | 2014 | Journal of Arid Land2014，6，1： | 4 |
| 3 | Methods for calculating glacier area and length in a mountainous area based on remote-sensing data and a digital elevation model显示文摘In a mountainous region, the glacier area and length extracted form the satellite imagery data is the projected area and length of the land surface, which can't be representative of the reality; there are always some errors. In this paper, the methods of calculating glacier area and length calculation were put forward based on satellite imagery data and a digital elevation model (DEM). The pure pixels and the mixed pixels were extracted based on the linear spectral un-mixing approach, the slop of the pixels was calculated based on the DEM, then the area calculation method was presented. The projection length was obtained from the satellite imagery data, and the elevation differences was calculated from the DEM. The length calculation method was presented based on the Pythagorean theorem. For a glacier in the study area of western Qilian Mountain, northwestern China, the projected area and length were 140.93 km2 and 30.82 km, respectively. This compares with the results calculated by the methods in this paper, which were 155.16 km2 and 32.11 km respectively, a relative error of the projected area and length extracted from the LandSat Thematic Mapper (TM) image directly reach to -9.2 percent and -4.0 percent, respectively. The calculation method is more in accord with the practicality and can provide reference for some other object's area and length monitoring in a mountainous region. | JunZhan Wang YouJing Zhang WeiMin Zhang JianJun Qu Chen Chen | 2010 | Research in Cold and Arid Regions2010，2，4： | 4 |
| 4 | Process for improving the ladle free- opening rate for high aluminum steel in continuous casting显示文摘Steel 20Mn23AlV is a type of high aluminum steel with a very low ladle free-opening rate. The aluminum composition of 20Mn23AlV ranges from 1. 6% to 2. 45%,which is significantly higher than other types of steel.According to the real condition of 40 t ladle in steel-making plant of Baosteel Special Steel Company,previous works show that the key factors affecting the ladle free-opening rate of high aluminum steel in continuous casting are: sand material,accessories baking,ladle nozzle cleaning,the process and amount of adding sand,and the rate of argon stirring during refining. Therefore,improving the ladle filler sand quality,baking all of the raw materials,controlling the addition of ladle filler sand,cleaning the ladle nozzle,and optimizing argon stirring during the refining process can resolve the problem of a low ladle free-opening rate of high aluminum steel caused by the long ladle time of liquid steel. | LIU Junzhan ZHOU Tongjun LUO Hui | 2015 | Baosteel Technical Research2015，9，1： | 3 |
| 5 | Classification of full-polarization ALOS-PALSAR imagery using SVM in arid area of Dunhuang显示文摘Classification is an important process in interpretation of synthetic aperture radar(SAR) imagery. As an advanced instrument for remote sensing, the polarimetric SAR has been applied widely in many fields. The main aim of this paper is to explore the ability of the full-polarization SAR data in classification. The study area is a part of Dunhuang, Gansu Province, China. An L-band full-polarization image of Dunhuang which includes quad-polarization modes was acquired by the ALOS-PALSAR(Advanced Land Observing Satellite–the Phased Array type L-band Synthetic Aperture Radar). Firstly, new characteristic information was extracted by the difference operation, ratio operation, and principal component transform based on the full-polarization(HH, HV or VH, VV) modes SAR data. Then the single-, dual-, full-polarization SAR data and new SAR characteristic information were used to analyze quantitatively the classification accuracy based on the Support Vector Machines(SVM). The results show that classification overall accuracy of single-polarization SAR data is poor, and the highest is 56.53% of VV polarization. The classification overall accuracy of dual-polarization SAR is much better than single-polarization, the highest is 74.77% of HV & VV polarization data. The classification overall accuracy of full-polarization SAR is 80.21%, adding the difference characteristic information, ratio characteristic information and the first principal component(PC1) respectively, the overall accuracy increased by 3.09%, 3.38%, 4.14% respectively. When the full-polarization SAR data in combination with the all characteristic information, the classification overall accuracy reached to 91.01%. The full-polarization SAR data in combination with the band math characteristic information or the PC1 can greatly improve classification accuracy. | JunZhan Wang JianJun Qu WeiMin Zhang KeCun Zhang | 2016 | Research in Cold and Arid Regions2016，8，3： | 2 |
| 6 | Small-Mole- cule-Driven direct reprogramming of mouse fibroblasts into functional neurons 显示文摘 | Li Xiang Zuo Xiaohan Jing Junzhan | 2015 | Cell Stem Cell2015，17，2： | 1 |
| 7 | Microstructure andproperties of 3Dneedled-punched carbon/silicon carbide brakematerials显示文摘 | Fan Shangwu Zhang Litong Xu Yongdong Cheng Laifei Lou Jianjun Zhang Junzhan Yu Lin | 2007 | Composites Science and Technology2007，67，1112： | 1 |
| 8 | Micromachining features of TiC ceramic by femtosec- ond pulsed laser显示文摘 | ZHANG YING WANG YUQIAN ZHANG JUNZHAN | 2015 | Ceramics International2015，，41： | 1 |
| 9 | Microstructure and properties of 3D needle-punched carbon/silicon carbide brake materials显示文摘 | Shangwu Fan Litong Zhang Yongdong Xu Laifei Cheng Jianjun Lou Junzhan Zhang Lin Yu | 2007 | Composites Science and Technology2007，，11： | 1 |
| 10 | Preparation and friction behavior of carbon fiber reinforced silicon carbide matrix composites显示文摘 | Yongdong Xu Yani Zhang Laifei Cheng Litong Zhang Jianjun Lou Junzhan Zhang | 2006 | Ceramics International2006，，3： | 1 |
| 11 | Flow field research on bottom argon blowing in a 40 ton ladle显示文摘In order to improve argon blowing efficiency in a 40 ton ladle,numerical simulation and water simulation experiments of the bottom argon flowwere performed.Relationships among the ladle mixing time,slag eye area,different blowing flowrates,and different blowing positions(0,0.56 R,0.62 R,0.67R) are discussed.Results showed that the ladle mixing time decreased when the argon blowing brick distance(from bottom center of the ladle) increased,and decreased significantly when the blowing flowincreased from 70 to 130 L / h.When the blowing flowincreased and exceeded 130 L / h,the stirring effect tended to be stable,and there was little effect on the ladle mixing time.The slag eye area increased as the argon brick distance increased,and was larger when the argon blowbrick was near the ladle wall.Wall shear stress significantly increased as the brick distance increased and was concentrated at the slag wall near the argon flowbrick; this is called the most serious erosion wall.The average wall shear increased exponentially with increasing argon blowing brick distance. | ZHOU Tongjun LIU Junzhan LUO Hui | 2016 | Baosteel Technical Research2016，10，3： | 0 |
| 12 | Glacier extraction based on ASAR,DEM and texture feature of ASAR using SVM in the Western Qilian Mountains,Northwest China显示文摘This paper is focused on the method for extracting glacier area based on ENVISAT ASAR Wide Swath Modes(WSM) data and digital elevation model(DEM) data,using support vector machines(SVM) classification method.The digitized result of the glacier coverage area in the western Qilian Mountains was extracted based on Enhanced LandSat Thematic Mapper(ETM+) imagery,which was used to validate the precision of glacier extraction result.Because of similar backscattering of glacier,shadow and water,precision of the glacier coverage area extracted from single-polarization WSM data using SVM was only 35.4%.Then,texture features were extracted by the grey level co-occurrence matrix(GLCM),with extracted glacier coverage area based on WSM data and texture feature information.Compared with the result extracted from WSM data,the precision improved 13.2%.However,the glacier was still seriously confused with shadow and water.Finally,DEM data was introduced to extract the glacier coverage area.Water and glacier can be differentiated because their distribution area has different elevations;shadow can be removed from the classification result based on simulated shadow imagery created by DEM data and SAR imaging parameters;finally,the glacier coverage area was extracted and the precision reached to 90.2%.Thus,it can be demonstrated that the glacier can be accurately semi-automatically extracted from SAR with this method.The method is suitable not only for ENVISAT ASAR WSM imagery,but also for other satellite SAR imagery,especially for SAR imagery covering mountainous areas. | JunZhan Wang JianJun Qu WeiMin Zhang | 2012 | Research in Cold and Arid Regions2012，4，3： | 0 |
| 13 | A method to obtain soil-moisture estimates over bare agricultural fields in arid areas by using multi-angle RADARSAT-2 data显示文摘Soil moisture is an important parameter for agriculture, meteorological, and hydrological studies. This paper focuses on soil-moisture estimation methodology based on the multi-angle high-and low-incidence-angle mode RADARSAT-2 data obtained over bare agricultural fields in an arid area. Backscattering of the high-and low-incidence angles is simulated by using AIEM(advanced integral equation model), with the surface-roughness estimation model built based on the simulated data. Combining the surface-roughness estimation model with the backscattering model of the low-incidence-angle mode, a soil-moisture estimation method is put forward. First, the natural logarithm(ln) of soil moisture was obtained and then the soil moisture calculated. Soil moisture of the study area in Dunhuang, Gansu Province, was obtained based on this method; a good agreement was observed between the estimated and measured soil moisture. The coefficient of determination was 0.85, and the estimation precision reached 4.02% in root mean square error(RMSE). The results illustrate the high potential of the approach developed and RADARSAT-2 data to monitor soil moisture. | JunZhan Wang JianJun Qu LiHai Tan KeCun Zhang | 2018 | Research in Cold and Arid Regions2018，10，2： | 0 |
| 14 | A general mechanism of grain growth-Ⅰ.Theory显示文摘The behaviors of grain growth dominate the formation of the microstructure inside polycrystalline materials and thus strongly influence their practical performances.However,grain growth behaviors still remain ambiguous and thus lack a mathematical formula to describe the general evolution despite decades of efforts.Here,we propose a new migration model of grain boundary(GB)and further derive a mathematical expression to depict the general evolution of grain growth in the cellular structures.The expression incorporates the variables influencing growth rate(e.g.GB features,grain size and local grain size distribution)and thus reveals how the normal,abnormal and stagnant behaviors of grain growth occur in polycrystalline systems.In addition,our model correlates quantitatively GB roughening transition with grain growth behavior.The general growth theory may provide new insights into the GB thermodynamics and kinetics during the cellular structure evolution. | Jianfeng Hu Xianhao Wang Junzhan Zhang Jun Luo Zhijun Zhang Zhijian Shen | 2021 | Journal of Materiomics2021，7，5： | 0 |
| 15 | A general mechanism of grain growth-Ⅱ: Experimental显示文摘The formed microstructure inside polycrystalline materials strongly influences their practical performances,which process is mostly dominated by grain growth behaviors.However,the general evolution of grain growth behaviors,especial for the occurrence of abnormal grain growth and stagnant growth,remains ambiguous despite decades of efforts.Here,we investigate systematically the general evolution of grain growth behaviors by combining a new grain growth theory with grain growth experiments in SrTiO_(3) polycrystalline materials.The results demonstrate that the observed evolution of grain growth behaviors is in accord with the theoretical predictions,which reveals that the abnormal and stagnant behaviors of grain growth may intrinsically occur in polycrystalline systems due to the existence of nonzero step free energy for grain growth.Furthermore,the general growth theory reveals that normal grain growth results from the roughening transition of grain boundaries which corresponding to step free energy equal to zero.Besides the lower GB energy as commonly believed,the narrower grain size distribution is revealed to play an important role on the thermal stability of grains,which may lead to the counter-intuitive phenomenon of smaller nano-sized grains with higher thermal stability as recently reported in the literature.The general,quantitative growth theory may offer an accurate guidance for the microstructural design with optimal physical properties in polycrystalline materials. | Jianfeng Hu Junzhan Zhang Xianhao Wang Jun Luo Zhijun Zhang Zhijian Shen | 2021 | Journal of Materiomics2021，7，5： | 0 |
| 16 | Fabrication and Properties of Ti_3SiC_2/SiC Composites显示文摘Ti3SiC2/SiC composites were fabricated by reactive hot pressing method. Effects of hot pressing temperature, the content and particle size of SiC on phase composition, densification, mechanical properties and behavior of stress-strain of the composites were investigated. The results showed that: (1) Hot-pressing temperature influenced the phase composition of Ti3SiC2/SiC composites. The flexural strength and fracture toughness of composites increased with hot pressing temperature. (2) It became more difficult for the composites to densify when the content of SiC in composites increased. It need be sintered at higher temperature to get denser composite. The flexural strength and fracture toughness of composites increased when the content of SiC added in composites increased. However, when the content of SiC reached 50 wt%, the flexural strength and fracture toughness of composites decreased due to high content of pore in composites. (3) When the content of SiC was same, Ti3SiC2/SiC composites were denser while the particle size of SiC added in composites is 12.8 μm compared with the composites that the particle size of SiC added is 3 μm. The flexural strength and fracture toughness of composites increased with the increase of particle size of SiC added in composites. (4) Ti3SiC2/SiC composites were non-brittle fracture at room temperature. | YIN Hongfeng FAN Qiang REN Yun ZHANG Junzhan | 2008 | China's Refractories2008，17，1： | 0 |
| 17 | Synthesis of Si3N4 Powder Using Sawdust as Carbon Source显示文摘Si_3N_4 powder was synthesized by carbothermal reduction nitridation reaction using sawdust as carbon source and introducing SiO_2 by silica sol immersion.Effects of Si O2 content of silica sol,molding pressure,reaction temperature,reaction duration,and N_2 flow rate on phase compositions and microstructure of resultants were studied. The results show that using7. 5 mass% SiO_2 containing silica sol immersed sawdust as raw materials,the prepared Si3N4 powder is featured with high α-Si_3N_4 content,few impurities,etc. in the conditions of 1 450 ℃ of reaction temperature,9h of reaction duration,400 m L·min- 1of N_2 flow rate and 10 MPa of molding pressure. | MA Xiaochen YIN Hongfeng ZHANG Junzhan REN Yun | 2016 | China's Refractories2016，25，2： | 0 |
| 18 | Synthesis of SiC Whiskers from Silicon Nitride in Argon Atmosphere显示文摘SiC whiskers were synthesized by carbothermal reduction of silicon nitride. α-Si3N4 and β-Si3N4 powders were used as silicon sources, and graphite, active carbon and black carbon as carbon sources, as well as boron oxide as catalyst. The synthesized SiC whiskers were characterized by XRD and SEM. The results showed that the synthesizing temperature should be above 1 716 K; the decomposition of Si3N4 was the limited step in the synthesis of SiC whiskers; and catalyst not only offered the liquid condition, but also restricted the growth of SiC whiskers along one dimension. LS mechanism seems to explain well the growth of SiC whiskers. | ZHANG Ying JIANG Mingxue ZHANG Junzhan CUI Xiwen | 2009 | China's Refractories2009，18，1： | 0 |
| 19 | 在成纤维细胞中通过一个化学小分子诱导的类XEN状态实现直接重编程显示文摘文章简介直接谱系重编程已经成为了一种具备应用前景的制备目的细胞类型的新方法。在通过化学小分子将小鼠成纤维细胞诱导为多能干细胞形成的过程中。 | Xiang Li Defang Liu Yantao Ma Xiaomin Du Junzhan Jing Lipeng Wang Bingqing Xie Da Sun Shaoqiang Sun Xueqin Jin Xu Zhang Ting Zhao Jingyang Guan Zexuan Yi Weifeng Lai Ping Zheng Zhuo Huang Yanzhong Chang 柴真 Jun Xu 邓宏魁 | 2018 | 科学新闻2018，0，4： | 0 |
| 20 | Research and application of numerical simulation to optimization of ingot casting process显示文摘During the ingot casting process,the parametric changes of the molten steel pouring process often cause both ingot surface and internal quality defects. With the increasingly wide application of computers in industrial technology,numerical simulations of the molten steel pouring process enable predictions of the defects that will arise during the pouring and solidification process,especially for the molten steel flowduring the early stages of casting. In addition,using a computer to simulate the casting process of a 40 t ingot and solidification can prevent many defects. The simulation results indicate that controlling the pouring speed to less than 80 kg / s,hanging the casting powder in a mold with the hanging height maintained at 100-150 mm,and controlling the taper angle of the mold brick outlet to a suitable level can reduce the probability of slag entrapment and improve the internal and surface quality of the ingot. | ZHOU Tongjun LIU Junzhan LUO Hui | 2015 | Baosteel Technical Research2015，9，3： | 0 |
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