|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Study of Variable Turbulent Prandtl Number Model for Heat Transfer to Supercritical Fluids in Vertical Tubes显示文摘In order to improve the prediction performance of the numerical simulations for heat transfer of supercritical pressure fluids, a variable turbulent Prandtl number(Pr_t) model for vertical upward flow at supercritical pressures was developed in this study. The effects of Pr_t on the numerical simulation were analyzed, especially for the heat transfer deterioration conditions. Based on the analyses, the turbulent Prandtl number was modeled as a function of the turbulent viscosity ratio and molecular Prandtl number. The model was evaluated using experimental heat transfer data of CO_2, water and Freon. The wall temperatures, including the heat transfer deterioration cases, were more accurately predicted by this model than by traditional numerical calculations with a constant Pr_t. By analyzing the predicted results with and without the variable Pr_t model, it was found that the predicted velocity distribution and turbulent mixing characteristics with the variable Pr_t model are quite different from that predicted by a constant Pr_t. When heat transfer deterioration occurs, the radial velocity profile deviates from the log-law profile and the restrained turbulent mixing then leads to the deteriorated heat transfer. | TIAN Ran DAI Xiaoye WANG Dabiao SHI Lin | 2018 | Journal of Thermal Science2018,27,3: | 13 |
| 2 | Dynamic tensile properties and microstructural evolution of extruded EW75 magnesium alloy at high strain rates显示文摘The dynamic tensile properties and microstructural evolution of an extruded EW75 magnesium alloy deformed at ambient temperature and different high strain rates(from 1000 to 3000 s^(-1))along extrusion direction(ED)were investigated by Split Hopkinson Tension Bar(SHTB).The corresponding deformation mechanisms,texture evolution and microstructure changes were analyzed by optical microscope(OM),electron backscatter diffraction(EBSD)and transmission electron microscope(TEM).The results show that the extruded EW75 magnesium alloy along ED exhibits a conventional positive strain rate sensitivity that the dynamic flow stresses increase with in creasing strain rate.Texture measurements show that after dynamic tension,the initial weak texture of extruded EW75 magnesium alloy tansforms to a relatively strong<10-10>//ED texture with increasing strain rates.The microstructural analysis demonstrates that dislocation motion are main deformatin mode to accommodate dynamic tensile deformation at high strain rates.In addition,the interactions of dislocation-dislocation and dislocation-second phase lead to the in crease of flow stress and strain hardening with increasing strain rate. | Jincheng Yu Bo Song Dabiao Xia Xun Zeng Yuanding Huang Norbert Hort Pingli Mao Zheng Liu | 2020 | Journal of Magnesium and Alloys2020,8,3: | 7 |
| 3 | Effects of Fe concentration on microstructure and corrosion of Mg-6Al-1Zn-xFe alloys for fracturing balls applications显示文摘Mg-6A1-1 Zn-xFe (x = 0,1,3,5 and 7 wt%) alloys were prepared by powder metallurgy and followed by hot extrusion. Majority of Fe element exists as insoluble particles in the alloys. The as-extruded alloys showed higher degradable rates but less stable mechanical properties than as-annealed alloys. Corrosion rate of all the alloys increased with increasing Fe concentration, reaching 2.4 mL cm^-2 h^-1.0.2% yield strength of all the alloys was higher than 150 MPa. In short, Mg-6A1-1 Zn-xFe alloys have an attractive combination of corrosion and mechanical properties, which holds a bright future for fracturing balls applications. | Cheng Zhang Liang Wu Guangsheng Huang Lin Chen Dabiao Xia Bin Jiang Andrej Atrens Fusheng Pan | 2019 | Journal of Materials Science & Technology2019,35,9: | 5 |
| 4 | The Tibetan Plateau Surface–Atmosphere Coupling System and Its Weather and Climate Effects: The Third Tibetan Plateau Atmospheric Science Experiment显示文摘The Tibetan Plateau(TP) is a key area affecting forecasts of weather and climate in China and occurrences of extreme weather and climate events over the world. The China Meteorological Administration, the National Natural Science Foundation of China, and the Chinese Academy of Sciences jointly initiated the Third Tibetan Plateau Atmospheric Science Experiment(TIPEX-Ⅲ) in 2013, with an 8–10-yr implementation plan. Since its preliminary field measurements conducted in 2013, routine automatic sounding systems have been deployed at Shiquanhe, Gaize, and Shenzha stations in western TP, where no routine sounding observations were available previously. The observational networks for soil temperature and soil moisture in the central and western TP have also been established. Meanwhile, the plateau-scale and regional-scale boundary layer observations, cloud–precipitation microphysical observations with multiple radars and aircraft campaigns, and tropospheric–stratospheric air composition observations at multiple sites, were performed. The results so far show that the turbulent heat exchange coefficient and sensible heat flux are remarkably lower than the earlier estimations at grassland, meadow, and bare soil surfaces of the central and western TP. Climatologically, cumulus clouds over the main body of the TP might develop locally instead of originating from the cumulus clouds that propagate northward from South Asia. The TIPEX-Ⅲ observations up to now also reveal diurnal variations, macro-and microphysical characteristics, and water-phase transition mechanisms, of cumulus clouds at Naqu station. Moreover, TIPEX-Ⅲ related studies have proposed a maintenance mechanism responsible for the Asian 'atmospheric water tower' and demonstrated the effects of the TP heating anomalies on African, Asian, and North American climates. Additionally, numerical modeling studies show that the Γ distribution of raindrop size is more suitable for depicting the TP raindrop characteristics compared to the M–P distribution, the overestimation of sensible heat flux can be reduced via modifying the heat transfer parameterization over the TP, and considering climatic signals in some key areas of the TP can improve the skill for rainfall forecast in the central and eastern parts of China. Furthermore, the TIPEX-Ⅲ has been promoting the technology in processing surface observations, soundings, and radar observations, improving the quality of satellite retrieved soil moisture and atmospheric water vapor content products as well as high-resolution gauge–radar–satellite merged rainfall products, and facilitating the meteorological monitoring, forecasting, and data sharing operations. | Ping ZHAO Yueqing LI Xueliang GUO Xiangde XU Yimin LIU Shihao TANG Wenming XIAO Chunxiang SHI Yaoming MA Xing YU Huizhi LIU La JIA Yun CHEN Yanju LIU Jian LI Dabiao LUO Yunchang CAO Xiangdong ZHENG Junming CHEN An XIAO Fang YUAN Donghui CHEN Yang PANG Zhiqun HU Shengjun ZHANG Lixin DONG Juyang HU Shuai HAN Xiuji ZHOU | 2019 | Journal of Meteorological Research2019,33,3: | 4 |
| 5 | On dissipative gradient effect in higher-order strain gradient plasticity: the modelling of surface passivation显示文摘The phenomenological flow theory of higher-order strain gradient plasticity proposed by Fleck and Hutchinson(J.Mech.Phys.Solids,2001)and then improved by Fleck and Willis(J.Mech.Phys.Solids,2009)is used to investigate the surface-passivation problem and micro-scale plasticity.An extremum principle is stated for the theory involving one material length scale.To solve the initial boundary value problem,a numerical scheme based on the framework of variational constitutive updates is developed for the strain gradient plasticity theory.The main idea is that,in each incremental time step,the value of the effective plastic strain is obtained through the variation of a functional in regard to effective plastic strain,provided the displacement or deformation gradient.Numerical results for elasto-plastic foils under tension and bending,thin wires under torsion,are given by using the minimum principle and the numerical scheme.Implications for the role of dissipative gradient effect are explored for three non-proportional loading conditions:(1)stretch-passivation problem,(2)bending-passivation problem,and(3)torsion-passivation problem.The results indicate that,within the Fleck-Hutchinson-Willis theory,the dissipative length scale controls the strengthening size effect,i.e.the increase of initial yielding strength,while the surface passivation gives rise to an increase of strain hardening rate. | Fenfei Hua Dabiao Liu | 2020 | Acta Mechanica Sinica2020,36,4: | 2 |
| 6 | Precipitation of Crystallized Hydrated Iron (~I) Vanadate from Industrial Vanadium Leaching Solution显示文摘 | Chen Liang Liu Fengqiang Li Dabiao | 2011 | Hydrometal-lurgy2011,105,34: | 1 |
| 7 | Hall-Petch effect and strain gradient effect in the torsion of thin gold wires显示文摘 | Zhipeng Gan Yuming He Dabiao Liu Bo Zhang Lei Shen | 2014 | Scripta Materialia2014,,: | 1 |
| 8 | Association between the nasopharyngeal microbiome and metabolome in patients with COVID-19显示文摘SARS-CoV-2,the causative agent for COVID-19,infect human mainly via respiratory tract,which is heavily inhabited by local microbiota.However,the interaction between SARS-CoV-2 and nasopharyngeal microbiota,and the association with metabolome has not been well characterized.Here,metabolomic analysis of blood,urine,and nasopharyngeal swabs from a group of COVID-19 and non-COVID-19 patients,and metagenomic analysis of pharyngeal samples were used to identify the key features of COVID-19.Results showed lactic acid,L-proline,and chlorogenic acid methyl ester(CME)were significantly reduced in the sera of COVID-19 patients compared with non-COVID-19 ones.Nasopharyngeal commensal bacteria including Gemella morbillorum,Gemella haemolysans and Leptotrichia hofstadii were notably depleted in the pharynges of COVID-19 patients,while Prevotella histicola,Streptococcus sanguinis,and Veillonella dispar were relatively increased.The abundance of G.haemolysans and L.hofstadii were significantly positively associated with serum CME,which might be an anti-SARS-CoV-2 bacterial metabolite.This study provides important information to explore the linkage between nasopharyngeal microbiota and disease susceptibility.The findings were based on a very limited number of patients enrolled in this study;a larger size of cohort will be appreciated for further investigation. | Jing Liu Sheng Liu Zhao Zhang Xuejun Lee Wenxuan Wu Zhanlian Huang Ziying Lei Wenxiong Xu Dabiao Chen Xing Wu Yang Guo Liang Peng Bingliang Lin Yutian Chong Xiangyu Mou Mang Shi Ping Lan Tao Chen Wenjing Zhao Zhiliang Gao | 2021 | Synthetic and Systems Biotechnology2021,6,3: | 0 |
| 9 | Canonical Correlation Factors Causing the Formation of Accumulated Sand-belts along the Oasis Fringe in Hexi Corridor显示文摘Accumulated sand-belts refer to those formed along the oasis fringe,especially at the upwind location,due to the accumulation of sand blocked by farmland windbreak. In the 60 years since the foundation of new China,a lot of trees have been planted for desertification combating in northwest and north China,thus,accumulated sand-belts were formed at the upwind location. The formation and the ecological effects of the accumulated sand-belts along the oasis fringe is a new scientific concern. To study the formation causes of these belts in Hexi corridor,21 samples were selected,and the height / width of the belts,as well as the vegetation,soil,soil moisture and climatic factors were investigated. This paper analyzed the correlation between the height / width of the belts and the vegetation,soil,soil moisture and climatic factors using the methods of variance analysis,correlation analysis and canonical correlation analysis. The results indicate that: the accumulated sand-belts take a trend of being high and wide in the east whereas low and narrow in the west,and most of the parts tend to be stable; the species on the belts are dominated by Tamarix austromongolica,the vegetation cover and the pure vegetation cover of different dominant species on the leeward slope of the accumulated sand-belts vary significantly. The canonical correlation analysis shows that: the height and width of accumulated sand-belt is the interaction of precipitation,distance to the sand source,leeward vegetation cover and annual average wind speed. Moreover,the height of accumulated sand-belts are negatively correlated to the soil moisture at the depth of 30- 50 cm,air humidity and leeward vegetation cover,and the width of the belts is also negatively correlated with the distance to the sand source. The ecological effects of the accumulated sand-belts are both positive( stopping sands from moving into farmland,protective role as an obstacle)and negative( when the belts decay and activate one day,they will become the new sand sources). At present,there are no signs showing the negative effects of the belts. The ecological effects of the accumulated sand-belts are: firstly the protective role as an obstacle,and secondly to intercept and reduce the sands moving into farmlands. | Chang Zhaofeng Wang Qiangqiang Zhang Jianhui Tang Jinnian Zhu Shujuan Fan Baoli Zhang Dabiao Liu Shizeng Zhang Guozhong Li Aide | 2014 | Animal Husbandry and Feed Science2014,6,5: | 0 |
| 10 | Global Warming:Increases in the Instability of Climate in Minqin Desert Area显示文摘The instability of climate in Minqin desert area during the process of global warming was analyzed based on meteorological data during 1961-2013. The results show that the instability of monthly average temperature in January and April increased. Isothermal date in February was 10.36 d earlier from 1961 to 2013. The instability of extreme maximum temperature in December and January enhanced. The instability of extreme minimum temperature in July increased. The coefficient of variation of extreme minimum temperature in May was up to 287.3%. The instability of average precipitation in January enhanced. At the same time,the stability of annual average precipitation increased. The stability of climate is more worthy of attention. | Zhang Dabiao Chang Zhaofeng Wang Dawei Han Fugui Duan Xiaofeng Wang Qiangqiang Zhang Jianhui | 2016 | Meteorological and Environmental Research2016,7,6: | 0 |
| 11 | Pollution characteristics of peroxyacetyl nitrate in karst areas in Southwest China显示文摘桂林是世界著名的地处喀斯特地区的旅游胜地,其光化学污染问题日益严重,过氧乙酰硝酸酯(PAN)被认为是光化学污染的可靠指标,也是本研究的重点.本研究于2021年10月首次观测了桂林的PAN的浓度为0.087-2.559ppb,同时探讨了PAN典型高值过程的成因.此次污染主要来源于东北方向污染气团的水平和高空输送,同时,高温,强辐射和低湿度等气象条件也促进了本地PAN的形成.本研究同时估算了桂林市的O3背景浓度为20.347ppb.这项研究为城市的光化学污染控制工作提供了理论基础。 | Songjun Guo Xu Wei Hongjiao Li Wen Qin Yijun Mu Jiongli Huang Chuan Nong Junchao Yang Dabiao Zhang Hua Lin Jingying Mao Zhaoyu Mo | 2024 | Atmospheric and Oceanic Science Letters2024,17,2: | 0 |
| 12 | A MODIFIED TORSION PENDULUM FOR MEASURING THE SHEAR MODULUS OF A SINGLE MICRO-SIZED FILAMENT显示文摘A modified torsion pendulum apparatus is developed for measuring the shear modulus of single filaments with uniform micro-sized diameter. A single filament fixed at both ends and with a ring-shaped mass attached at the middle is used as a clamped-clamped torsion pendulum.The shear modulus of single filaments can be expressed as a function of the oscillation frequency of the torsion pendulum. The oscillation motion is measured with a CCD laser displacement sensor, and its frequency is determined by the Fast Fourier Transform(FFT) method. The shear moduli of three types of filaments: copper wires, tungsten wires and carbon fibers are accurately measured with this technique. It is found that the size effect in shear moduli of both copper wires and tungsten wires is minor. Finally, the error analysis of our measurement technique is presented in detail. | Dabiao Liu Yuming He Peng Hu Zhipeng Gan Huaming Ding | 2014 | Acta Mechanica Solida Sinica2014,27,3: | 0 |
| 13 | Ecological Effects of Accumulated Sand-belts along the Oasis Fringe in Hexi of Gansu显示文摘The accumulated sand-belts have formed along the oasis fringe,especially at the upwind areas of the desert area in Gansu Hexi of China during the process of desert control in recent 60 years. The accumulated sand-belt is a byproduct of desertification combating through afforestation and barriers-setting. This paper analyzed the data( including wind velocity / direction) of 21 sites on the accumulated sand-belt to evaluate its stability and ecological effects. The results showed that the accumulated sand-belt is in a stable state. It plays a significant role in weakening wind and this effect is enhanced with the increase of wind velocity. The height of accumulated sand-belt is an important factor characterizing its windproof function. When the wind velocity is higher than 2 m / s,the windproof area in the downwind places is 20 times greater than the height of the accumulated sand-belt. When the wind velocity is higher than 8 m / s,the wind velocity on the top of the accumulated sand-belt is less than that in the upwind open areas. When the air flow reaches the windward slope,its energy is released and reduced by uplifting along the slope and diversion towards the two wings. Wind deflector reduces the velocity of the prevailing wind on the windward slope. | Chang Zhaofeng Zhang Jianhui Wang Qiangqiang Zhu Shujuan Zhang Dabiao Fan Baoli Tang Jinnian Liu Shizeng | 2014 | Animal Husbandry and Feed Science2014,6,3: | 0 |
| 14 | Ulcerative colitis triggered by pegylated interferon alpha-2b in a patient with chronic hepatitis B: A case report and literature review显示文摘Interferon(IFN)is a multifaceted immunomodulator that is effective against many diseases,including chronic hepatitis B and chronic hepatitis C infection.IFN defends against viral infection,but may also cause various side effects,such as ulcerative colitis(UC).Herein,we present a case of UC triggered by pegylated interferon alpha-2b(PEG-IFN-α-2b)therapy in a patient with concurrent chronic hepatitis B(CHB)infection.The diagnosis was based on typical clinical symptoms,colonoscopy findings,colonic mucosal biopsy,and histopathology.Accordingly,treatment with mesalazine was initiated without stopping PEG-IFN-α-2b.Fortunately,UC relieved gradually without compromising the effects of treatment.Simultaneously,we conducted a literature review of previously published case reports on the side effect of UC in patients with underlying chronic hepatitis.Various reactions have been reported,including induction,exacerbation,and no change.This is the first report of UC triggered by PEG-IFN-α-2b in a CHB patient.We recommend that physicians pay attention to the rare side effect of UC during administration of PEG-IFN-α-2b.Mesalazine can relieve UC with sustained use of PEG-IFN-α-2b. | Zhishuo Mo Jian Tang Zeqian Wu Dabiao Chen Dongying Xie Peipei Wang | 2021 | Liver Research2021,5,2: | 0 |
| 15 | Modeling of Cyclic Bending of Thin Foils Using Higher-Order Strain Gradient Plasticity显示文摘The plastic behaviors of thin metallic foils,including size effect,Bauschinger effect,and passivation effect,are studied under cyclic bending condition using the strain gradient visco-plasticity theory.The finite element simulations are performed on the cyclic bending of the elasto-viscoplastic thin foils with passivated and unpassivated surfaces.The study is also conducted on the transition from a passivated surface to an unpassivated one.The roles of the dissipative and energetic gradient terms are emphasized.From the results,it is found that the dissipative gradient terms increase the yield strength,while the energetic gradient terms increase the strain hardening,resulting in an anomalous Bauschinger effect.Further,it is observed that the surface passivation effect increases both the normalized bending moment at initial yielding and strain hardening.The comparison between the numerical results of cases with and without passivation demonstrates that the switching of boundary conditions significantly affects the plastic behavior of the foils under cyclic bending. | Tong Luo Fenfei Hua Dabiao Liu | 2022 | Acta Mechanica Solida Sinica2022,35,4: | 0 |
| 16 | Relating Initial Texture to Deformation Behavior During Cold Rolling and Static Recrystallization Upon Subsequent Annealing of an Extruded WE43 Alloy显示文摘Deformation behaviors during cold rolling and static recrystallization behaviors upon subsequent annealing of an extruded WE43 alloys with different initial textures were investigated in this study.Three types of differently textured WE43 initial alloys were labeled as samplesⅠ,ⅡandⅢ.The results showed that multiple twinning modes and basal slip dominated the deformation of samples during cold rolling.Cold-rolled sampleⅠactivated the larger number of double twins with high strain energy,accompanied by the more uniform strain distribution,than cold-rolled samplesⅡandⅢ.During subsequent annealing,recrystallized grains preferentially occurred in double twins,twin-twin intersections and grain boundaries,thereby making cold-rolled sampleⅠhave the more rapid recrystallization rate.Similar recrystallization textures formed in three types of cold-rolled samples at the recrystallization nucleation stage,and they never largely changed with the annealing time due to the uniform grain growth induced by the solute drag and the precipitation pinning at grain boundaries.After full recrystallization,the grain growth was controlled by the solute drag,instead of precipitates which were re-dissolved into the matrix.Finally,the nucleation and growth kinetics of static recrystallization were calculated,and the effects of initial texture on activation energies of recrystallization nucleation and growth were discussed. | Qinghang Wang Haowei Zhai Hongbo Xia Lintao Liu Junjie He Dabiao Xia Hong Yang Bin Jiang | 2022 | Acta Metallurgica Sinica(English Letters)2022,35,11: | 0 |