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NUMERICAL PREDICTION OF VORTEX FLOWIN HYDRAULIC TURBINE DRAFT TUBE FOR LES

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Journal of Hydrodynamics 2005年第4期17卷 448-454页

作者： liu xiao-bing ZENG Yong-zhong CAO Shu-you School of Energy and Environment Xihua University Chengdu 610039 China State Key Hydraulics Laboratory of High Speed Flows Sichuan University Chengdu 610065 China

The three-dimensional unsteady turbulent flow is studied numerically in the whole flow passage of hydraulic turbine, and vortex flow in the draft tube is predicted accurately in this paper. The numerical prediction is based on the Navier-Stokes equations and Large-Eddy Simulation （LES） model. The SIMPLE algorithm with the body fitted coordinate and tetrahedroid grid system is applied for the solution of the discretization governing equations.

关键词： vortex flow hydraulic turbine draft tube numerical prediction LES

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Biomedical and Environmental Sciences 2021年第4期34卷 324-329页

作者： liu xiao bing WANG Jun LI Ya Jie TAN Hong Xing liu Yan Yan YU Wei ZHANG Yu YANG Li Chen PIAO Jian Hua liu xiao Li YANG xiao Guang Shenzhen Center for Chronic Disease Control Shenzhen 518020GuangdongChina Key Laboratory of Trace Element Nutrition of National Health Commission National Institute of Nutrition and HealthChinese Center for Disease Control and PreventionBeijing 100050China Changzhi Medical College Changzhi 047500ShanxiChina

Iodine is an essential component of thyroid hormones’biosynthesis and is crucial for normal growth and healthy development[1].If the amount of dietary iodine intake cannot match the long-term requirement,regardless of whether it is excessively low or high,it can cause various thyroid dysfunctions,including hyperthyroidism,hypothyroidism,and autoimmune thyroid diseases[2].

关键词： intake diseases dietary

Bacterial Community Structure in a Mollisol Under Long-Term Natural Restoration, Cropping, and Bare Fallow History Estimated by PCR-DGGE

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Pedosphere 2009年第2期19卷 156-165页

作者： WANG Guang-Hua JIN Jian liu Jun-Jie CHEN Xue-Li liu Ju-Dong liu xiao-bing Key Laboratory of Black Soil Ecology Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Harbin 150081 China

Soil microbial biomass and community structures are commonly used as indicators for soil quality and fertility. A investigation was performed to study the effects of long-term natural restoration, cropping, and bare fallow managements on the soil microbial biomass and bacterial community structures in depths of 0-10, 20 30, and 40-50 cm in a black soil （Mollisol）. Microbial biomass was estimated from chloroform fumigation-extraction, and bacterial community structures were determined by analysis of 16S rDNA using polymerase chain reaction-denaturing gradient gel electrophoresis （PCR- DGGE）. Experimental results showed that microbial biomass significantly declined with soil depth in the managements of restoration and cropping, but not in the bare fallow. DGGE profiles indicated that the band number in top 0-10 cm soils was less than that in depth of 20-30 or 40-50 cm. These suggested that the microbial population was high but the bacterial community structure was simple in the topsoil. Cluster and principle component analysis based on DGGE banding patterns showed that the bacterial community structure was affected by soil depth more primarily than by managements, and the succession of bacterial community as increase of soil depth has a similar tendency in the three managements. Fourteen predominating DGGE bands were excised and sequenced, in which 6 bands were identified as the taxa of Verrueomicrobia, 2 bands as Actinobacteria, 2 bands as α-Proteobacteria, and the other 4 bands as 8-Proteobacteria, Aeidobacteria, Nitrospira, and unclassified bacteria. In addition, the sequences of 11 DGGE bands were closely related to uncultured bacteria. Thus, the bacterial community structure in black soil was stable, and the predominating bacterial groups were uncultured.

关键词： bacterial community black soil denaturing gradient gel electrophoresis (DGGE) polymerase chain reaction (PCR) soil depth

Characterization of root-associated bacterial community structures in soybean and corn using locked nucleic acid(LNA) oligonucleotide-PCR clamping and 454 pyrosequencing

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Journal of Integrative Agriculture 2016年第8期15卷 1883-1891页

作者： YU Zhen-hua YU Jiang Makoto Ikenaga Masao Sakai liu xiao-bing WANG Guang-hua Key Laboratory of Mollisols Agroecology Northeast Institute of Geography and Agroecology Chinese Academy of Sciences College of Agronomy Northeast Agricultural University Faculty of Agriculture Kagoshima University

supported in part by grants from the Strategic Priority Research Program of Chinese Academy of Sciences （XDB15010103）;the National Natural Science Foundation of China （41201247）

关键词： bacterial diversity high-throughput sequencing corn soybean SSU rRNA genes

Thickening of Non-Ferroelectric Capacitive Layers with Enhanced Domain Switching Speed in Polyvinylidence Fluoride Copolymer Thin Films

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Chinese Physics Letters 2011年第10期28卷 236-239页

作者： liu xiao-bing MENG Jian-Wei JIANG An-Quan WANG Jian-Lu State Key Laboratory of ASIC and System Department of MicroelectronicsFudan UniversityShanghai 200433 National Laboratory Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083

The large coercive field of domain switching in poly(vinylidene fluoride-trifluoroethylene)thin films is in much part due to the contribution of nonpolar impurity phases rather than the manifestation of an intrinsic domain switching mechanism of the ferroelectric *** coincidentally derive the equivalent electrical capacitance for the total non-ferroelectric capacitive layers from either domain switching current transient or voltage dependence of the switched ***,the non-ferroelectric capacitance reduces by more than 71%with the enhancement of domain switching speed spanning over 5 orders of magnitude in company with the continuous reduction of the remanent polarization,which suggests the thickening of the above capacitive layers with enhanced domain switching speed.

关键词： ferroelectric capacitance Copolymer

Temporal and Spatial Dynamics of Bacterial Community in the Rhizosphere of Soybean Genotypes Grown in a Black Soil

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Pedosphere 2009年第6期19卷 808-816页

作者： JIN Jian WANG Guang-Hua liu xiao-bing liu Jii-Dong CHEN Xue-Li S. J. HERBERT Key Lab of Black Soil Ecology Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Harbin 150081 (China) Department of Plant Soil and Insect Sciences University of Massachusetts Amherst MA 01003 (USA)

The dynamics of rhizosphere microbial communities is important for plant health and productivity, and can be influenced by soil type, plant species or genotype, and plant growth stage. A pot experiment was carried out to examine the dynamics of microbial communities in the rhizosphere of two soybean genotypes grown in a black soil in Northeast China with a long history of soybean cultivation. The two soybean genotypes, Beifeng 11 and Hai 9731, differing in productivity were grown in a mixture of black soil and siliceous sand. The bacterial communities were compared at three zone locations including rhizoplane, rhizosphere, and bulk soil at the third node （V3）, early flowering （R1）, and early pod （R3） stages using polymerase chain reaction-denaturing gradient gel electrophoresis （PCR-DCGE） of 16S rDNA. The results of principal component analyses （PCA） showed that the bacterial community structure changed with growth stage. Spatially, the bacterial communities in the rhizoplane and rhizosphere were significantly different from those in the bulk soil. Nevertheless, the bacterial communities in the rhizoplane were distinct from those in the rhizosphere at the V3 stage, while no obvious differences were found at the R1 and R3 stages. For the two genotypes, the bacterial community structure was similar at the V3 stage, but differed at the R1 and R3 stages. In other words, some bacterial populations became dominant and some others recessive at the two later stages, which contributed to the variation of the bacterial community between the two genotypes. These results suggest that soybean plants can modify the rhizosphere bacterial communities in the black soil, and there existed genotype-specific bacterial populations in the rhizospbere, which may be related to soybean productivity.

关键词： PCR-DGGE plant growth stage 16S rDNA soybean productivity

Evaluation of Erythrocyte Iron Incorporation in Beijing Prepubertal Children Using a Single Stable Isotope Tracer Method

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Biomedical and Environmental Sciences 2020年第6期33卷 414-420页

作者： ZHANG Yu LI Ya Jie REN Tong Xiang liu xiao bing YANG Li Chen PAO Jian Hua WANG Jurr YANG xiao Guang Key Laboratory of Trace Element Nutrition MOHChinese Center for Disease Control and PreventionBeijing 100050China Department of Preventive Medicine Changzhi Medical CollegeChangzhi 046000ShanxiChina National Institute of Metrology Beijing 100029China

Objective To analyze the rate of erythrocyte iron incorporation and provided guidance for the iron nutrition for prepubertal *** Fifty-seven prepubertal children of Beijing were involved in this study and each subject was orally administered 3 mg of 57 Fe twice daily to obtain a total of 30 mg 57 Fe after a 5-d period. The stable isotope ratios in RBCs were determined in 14 th day, 28 th day, 60 th day, and 90 th day. The erythrocyte incorporation rate in children was calculated using the stable isotope ratios, blood volume and body iron *** The percentage of erythrocyte 57 Fe incorporation increased starting 14 th day, reached a peak at 60 d(boys: 19.67% ± 0.56%, girls: 21.33% ± 0.59%) and then decreased. The erythrocyte incorporation rates of 57 Fe obtained for girls in 60 th day was significantly higher than those obtained for boys(P < 0.0001).Conclusions The oral administration of 57 Fe to children can be used to obtain erythrocyte iron incorporation within 90 d. Prepubertal girls should begin to increase the intake of iron and further studies should pay more attention to the iron status in prepubertal children.

关键词： Stable isotope tracer technique Iron Erythrocyte incorporation rate Beijing prepubertal children MC-ICP-MS

NUMERICAL PREDICTION OF SILT ABRASIVE EROSION IN HYDRAULIC TURBINE

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Journal of Hydrodynamics 1999年第1期11卷 103-110页

作者： Zhang Jia-chuan liu xiao-bing (Sichuan Institute of Technology, Chengdu 611744, P. R. China) Sichuan Inst of Technology Chengdu China

Numerical investigations on silt abrasive erosion of hydraulic turbine for low sand concentration were reported. The turbulent flow velocity fields, pressure distributions and trajectories of sand particle in the hydraulic turbine have been numerically calculated by mixed Eulerian-Lagrangian turbulence model, which was based on a particle-source-in-cell numerical technique for two-phase flows. The Eulerian equations were used for the description of liquid phase flow, the solid particles were treated within Lagrangian framework. The sand particle rebound model and erosion wear model in flow field were also presented. The erosion wear rates of the guide vane of Gezhouba hydraulic turbine were calculated. The numerical predictions show a good agreement with the tests.

关键词： Two phase flow Sand Silt Particles (particulate matter) Turbulent flow Erosion Abrasives Numerical analysis

Using an Alternative Method to Estimate the Status of Iodine Nutrition in Pregnant Women

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Biomedical and Environmental Sciences 2018年第7期31卷 535-538页

作者： liu xiao bing WU Meng ZHANG Yu WANG Lei PIAO Jian Hua YANG Li Chen YANG xiao Guang Key Laboratory of Trace Element Nutrition of National Health and Family Planning Commission National Institute of Nutrition and Health of Chinese Center for Disease Control and Prevention Beijing 100050 China Maternal & Child Health Care Hospital of Shaanxi Province Xian 710000 Shaanxi China Chao Yang District Center for Disease Control and Prevention Beijing 100021 China

Iodine is an element that is essential for the synthesis of thyroid *** intake of dietary iodine has been recognized as a critical factor for maintaining *** is a well-known fact that iodine deficiency can impede the production of thyroid hormones in both the mother and fetus,which increases the risk of brain damage in the fetal stage.

关键词： Cr UIC Using an Alternative Method to Estimate the Status of Iodine Nutrition in Pregnant Women UIE