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| 1 | Numerical Simulation and Analysis of Solid-liquid Two-phase Flow in Centrifugal Pump显示文摘The flow with solid-liquid two-phase media inside centrifugal pumps is very complicated and the relevant method for the hydraulic design is still immature so far.There exist two main problems in the operation of the two-phase flow pumps,i.e.,low overall efficiency and severe abrasion.In this study,the three-dimensional,steady,incompressible,and turbulent solid-liquid two-phase flows in a low-specific-speed centrifugal pump are numerically simulated and analyzed by using a computational fluid dynamics(CFD) code based on the mixture model of the two-phase flow and the RNG k-two-equation turbulence model,in which the influences of rotation and curvature are fully taken into account.The coupling between impeller and volute is implemented by means of the frozen rotor method.The simulation results predicted indicate that the solid phase properties in two-phase flow,especially the concentration,the particle diameter and the density,have strong effects on the hydraulic performance of the pump.Both the pump head and the efficiency are reduced with increasing particle diameter or concentration.However,the effect of particle density on the performance is relatively minor.An obvious jet-wake flow structure is presented near the volute tongue and becomes more remarkable with increasing solid phase concentration.The suction side of the blade is subject to much more severe abrasion than the pressure side.The obtained results preliminarily reveal the characteristics of solid-liquid two-phase flow in the centrifugal pump,and are helpful for improvement and empirical correction in the hydraulic design of centrifugal pumps. | ZHANG Yuliang LI Yi CUI Baoling ZHU Zuchao DOU Huashu | 2013 | Chinese Journal of Mechanical Engineering2013，26，1： | 55 |
| 2 | External Characteristics and Internal Flow Features of a Centrifugal Pump during Rapid Startup显示文摘Centrifugal pumps always work under steady conditions,and many researches focus on the steady operation.But transient conditions,such as sudden startup and shutdown,are inevitable.The researches on the inner flow of centrifugal pumps under transient conditions have been done,and they show that the transient operation is different from the steady operation.In order to research the evolution of unsteady flow in a centrifugal pump under transient conditions,and to investigate the mechanism of transient effects by analyzing the unsteady flow in a centrifugal pump,the external characteristic experiment and the internal flow numerical calculation of the centrifugal pump with an open impeller during startup is presented.The relationships of the rotation speed,capacity and head between start-time are obtained by the external characteristics experiment.The numerical calculations under startup process are carried out by using the k-e model and N-S equation.The distribution of velocity and pressure in the inner channel of the tested pump was obtained by choosing fourteen start-time points and twelve geometrical points in the impeller channel during startup.The calculation results show that the velocity and the pressure increase linearly with the start-time before rotation's speed gets steady,then changes almost horizontally after rotation speed becomes steady,then fluctuates until being steady.The internal flow characteristics are in good agreement with the external characteristic experimental results and numerical calculation.The simulation methods and results make the basis for the diagnosis and optimization of under flow in the centrifugal pump during transient operation. | ZHU Zuchao GUO Xiaomei CUI Baoling LI Yi | 2011 | Chinese Journal of Mechanical Engineering2011，24，5： | 14 |
| 3 | Palaeogeomorphology and its control on the development of sequence stratigraphy and depositional systems of the Early Silurian in the Tarim Basin显示文摘The Silurian in the Tarim Basin was deposited on the basement deformed by the Caledonian tectonic movements at the end of the Late Ordovician. The development and distribution of sedimentary sequences of the Early Silurian have been clearly controlled by the palaeogeomorphology of the Late Ordovician. Based on unconformity characteristics and distribution of erosion, several zones can be differentiated including a high uplifted erosion zone, a transitional slope zone and a depression zone. The central and west Tabei Uplift zones show high angular unconformity and intense erosion. The Tarim Basin in the late Ordovician shows characteristics of higher in the west, lower in the east while higher in the south, lower in the north. The Early Silurian mainly developed transgressive and highstand systems tracts on the whole, while the lowstand systems tract only developed partly below the slope break. The palaeogeomorphology controlled the clastic source supply and deposit distribution. Braided delta system and tidal flat–estuary system were deposited. The duration of uplifting of the Tazhong paleouplift was longer than that of the Tabei paleo-uplift, and deposition was later. This led to the lower and middle members of the Kepingtage Formation missing in that area. As a large-scale transgression occurred during the deposition period of the upper member of the Kepingtage Formation, sediment from the west of the basin was transported and deposited by tides and waves, forming tidal–marine debris systems above the uplift. Proximal alluvial fan and fan delta coarse clastic deposits developed in proximal uplift zone in the east and southeast of the basin, and braided delta put forward to the transitional zone between the edge of uplift and the sea. Large-scale tidal channel, sub-distributary channel and mouth bar of the delta front can form favorable reservoirs, and they are primary targets for oil and gas exploration. This research on sequence–depositional systems development and distribution controlled by palaeogeomorphology is significant in guiding the prediction of reservoir sandstones. | Liu Jingyan Lin Changsong Cai Zhenzhong Zhu Yongfeng Yang Yongheng Peng Li Si Baoling Huang Zhen Li Huanpu Xu Yingcai Su Zhenzhen | 2010 | Petroleum Science2010，7，3： | 13 |
| 4 | Progress and records in the study of endogenetic mineralization during collisional orogenesis显示文摘To develop and perfect the theory of plate tectonics and regional metallogeny, metal-logenesis during collisional orogenesis should be thoroughly studied and will attract increasing at-tention of more and more scientists. This paper presents the main aspects of research and discus-sions on metallogenesis during collisional orogenesis after the development of plate tectonics, and accordingly divides the study history into two stages, i.e. the junior stage during 1971-1990 and the senior stage after 1990. Beginning with the negation of mineralization in the collision regime by Guild (1971), the focus of study was put on whether there occurred any mineralization during collisional orogenesis at the junior stage. At the senior stage, which is initiated by the advance of met-allogenic and petrogenic model for collisional orogenesis, scientists begin to pay their attention to the geodynamic mechanism of metallogenesis, spatial and temporal distribution of ore deposits, ore-forming fluidization, relationship | Yanjing Chen Huayong Chen Yulin Liu Guangjun Guo Yong Lai Shan Qin Baoling Huang Zengjie Zheng Yinghui Sui Chao Li et al. | 2000 | Chinese Science Bulletin2000，45，1： | 13 |
| 5 | Computational Analysis of Centrifugal Pump Delivering Solid-liquid Two-phase Flow during Startup Period显示文摘The transient behavior of centrifugal pumps during transient operating periods,such as startup and stopping,has drawn more and more attention recently because of urgent needs in engineering.Up to now,almost all the existing studies on this behavior are limited to using water as working fluid.The study on the transient behavior related to solid-liquid two-phase flow has not been seen yet.In order to explore the transient characteristics of a high specific-speed centrifugal pump during startup period delivering the pure water and solid-liquid two-phase flow,the transient flows inside the pump are numerically simulated using the dynamic mesh method.The variable rotational speed and flow rate with time obtained from experiment are best fitted as the function of time,and are written into computational fluid dynamics(CFD)code-FLUENT by using a user defined function.The predicted heads are compared with experimental results when pumping pure water.The results show that the difference in the transient performance during startup period is very obvious between water and solid-liquid two-phase flow during the later stage of startup process.Moreover,the time for the solid-liquid two-phase flow to achieve a stable condition is longer than that for water.The solid-liquid two-phase flow results in a higher impeller shaft power,a larger dynamic reaction force,a more violent fluctuation in pressure and a reduced stable pressure rise comparing with water.The research may be useful to understanding on the transient behavior of a centrifugal pump under a solid-liquid two-phase flow during startup period. | ZHANG Yuliang LI Yi ZHU Zuchao CUI Baoling | 2014 | Chinese Journal of Mechanical Engineering2014，27，1： | 13 |
| 6 | Nitrogen reduction using bioreactive thin-layer capping(BTC)with biozeolite: A field experiment in a eutrophic river显示文摘Bioreactive thin-layer capping(BTC)with biozeolite provides a potential remediation design that can sustainably treat N contamination from sediment and overlying water in eutrophic water bodies.Nitrogen(N)reduction using BTC with biozeolite was examined in a field incubation experiment in a eutrophic river in Yangzhou,Jiangsu Province,China.The biozeolite was zeolite with attached bacteria,including two isolated heterotrophic nitrifiers(Bacillus spp.)and two isolated aerobic denitrifiers(Acinetobacter spp.).The results showed that the total nitrogen(TN)reduction efficiency of the overlying water by BTC with biozeolite(with thickness of about 2 mm)reached a maximum(56.69%)at day 34,and simultaneous heterotrophic nitrification and aerobic denitrification occurred in the BTC system until day 34.There was a significant difference in the TN concentrations of the overlying water between biozeolite capping and control(t-test;p<0.05).The biozeolite had very strong in situ bioregeneration ability.Carbon was the main source of nitrifier growth.However,both dissolved oxygen(DO)and carbon concentrations affected denitrifier growth.In particular,DO concentrations greater than 3 mg/L inhibited denitrifier growth.Therefore,BTC with biozeolite was found to be a feasible technique to reduce N in a eutrophic river.However,it is necessary to further strengthen the adaptability of aerobic denitrifiers through changing domestication methods or conditions. | Zhenming Zhou Tinglin Huang Baoling Yuan | 2016 | Journal of Environmental Sciences2016，28，4： | 8 |
| 7 | Numerical Investigation of Pressure Distribution in a Low Specific Speed Centrifugal Pump显示文摘To study the pressure distribution of the volute casing, front casing and back casing in a prototype centrifugal pump, the pressure experiments and numerical simulations are carried out at six working conditions in this paper. The experimental results shows that the asymmetry of static pressure distribution on volute casing and front cavity is caused by the tongue of the volute and it may result in high radial and axial resultant force which can cause vibration and noise in the centrifugal pump. With the increasing of flow rate, the asymmetry of static pressure distribution and the magnitude of static pressure values reduce. The numerical results indicate that the pressure fluctuation near the tongue is strongest and it becomes slighter at point away from the tongue. With the increasing of flow rate, the local high-pressure region in impeller passage reduces and the flow becomes smoother accordingly, whereas the fluid speed becomes much higher which may cause further flow losses. The results predicted by numerical simulation are in coincident with the experimental ones. It shows that the turbulence model for simulating the flow field in centrifugal pumps is feasible. | JIA Xiaoqi CUI Baoling ZHU Zuchao YU Xiaoli | 2018 | Journal of Thermal Science2018，27，1： | 7 |
| 8 | Unsteady Flow Characteristic of Low-Specific-Speed Centrifugal Pump under Different Flow-Rate Conditions显示文摘To investigate the unsteady flow characteristics in centrifugal pump, the flow field in a low-specific-speed centrifugal pump with complex impeller is numerically simulated under different conditions. The RNG κ-ε turbulence model and sliding mesh are adopted during the process of computation. The results show that the interaction between impeller and volute results in the unstable flow of the fluid, which causes the uneven distribution of pressure fluctuations around the circumference of volute. Besides the main frequency and its multiple frequency of pressure fluctuations in the centrifugal pump, the frequency caused by the long blades of complex impeller also plays a dominant role in the low-frequency areas. Furthermore, there exists biggish fluctuation phenomenon near the tongue. The composition of static pressure fluctuations frequency on the volute wall and blade outlet is similar except that the fluctuation amplitude near the volute wall reduces. In general, the different flow rates mainly have influence on the amplitude of fluctuation frequency in the pump, while have little effect on the frequency composition. | CUI Baoling CHEN Desheng XU Wenjing JIN Yingzi ZHU Zuchao | 2015 | Journal of Thermal Science2015，24，1： | 7 |
| 9 | Influence of olivine grains on K-Ar dating of Late-Cenozoic olivine basalts in eastern China显示文摘Five Late-Cenozoic olivine basalt samples, taken from 3 young volcanoes (Keluo, Lianhuashan and Qinglongshan) located in the north of Heilongjian Province, were dated by the conventional K-Ar dating method. The apparent ages of whole rock are (0.06±0.01) Ma,( 0.15±0.03) Ma, (0.17±0.02) Ma, (21.10±0.13) Ma and (24.46±0.10) Ma, respectively. In the crushed sample grains (mush number 80-100)olivine(including phynocryst and xenocryst)was picked out under a binocular microscope, then apparent ages obtained are (0.03±0.01) Ma, (0.06±0.01) Ma, (0.07±0.03) Ma, (2.31±0.02) Ma and (1.50±0.21) Ma, respectively. The apparent ages of the olivine-picked out sample are come down (younger)50 to over 90. There are a lot of the Late-Cenozoic volcanic olivine basalt outcropping in eastern China, probably the age-datings of those basalt samples in which olivine grains are unpicked out are older than the true geological ages. The inference and conclusion drawn from those datings should be renewed. | Zhiguo Mu Yulin Liu Baoling Huang | 1998 | Chinese Science Bulletin1998，43，19： | 7 |
| 10 | The role of P2X7 receptor in ATP-mediated human leukemia cell death: calcium influx-independent显示文摘P2X7 受体的激活导致阳离子的快速的、双向流动,引起包括 cytotoxicity 的生物回答的宽广范围。然而,调停 P2X7 的 cytotoxicity 的机制仍然保持大部分未经勘探。在我们的以前的学习,在正常条件下面的调停 P2X7 的钙反应的缺乏在 P2X7+ 造血的房间线被发现。在这研究,在房间的不同类型的调停 P2X7 的 cytotoxicity (P2X7 ? ,有钙反应的 P2X7+ ,和没有钙反应的 P2X7+) 被调查。我们的结果证明 P2X7 收缩筋,腺苷 5-triphosphate ( ATP )或2,3-O-( 4 benzoylbenzoyl )-ATP, dose-dependently 在测试的所有P2X7+房间减少了房间生存能力,包括为 调停P2X7 的钙反应否定的 J6-1 , LCL ,和 Namalva 房间,尽管这些效果比在有正常 P2X7 功能的 KG1a 房间观察的那些低。细胞毒素的效果能被 P2X7 对手,氧化 ATP 和 1- 堵住[N, O 二度(5-isoquinolinesulfonyl )-N-methyl-l-tyrosyl]-4-phenylpiperazine。另外, phosphatidylserine 的外表表现能以一种时间依赖者方式和 apoptotic 被检测词法变化能在 J6-1 房间在 P2X7 受体的激活以后被观察。而且,调停 P2X7 的毛孔形成能在低离子的条件下面,然而并非在低二价的条件下面在 KG1a 和 J6-1 房间被检测。这些效果不能在 P2X7 被观察吗?Ramos 房间。这些结果建议 P2X7 调停受体的细胞毒素的效果可以发生独立于钙反应。 | Xiujun Zhang Lijun Meng Baoling He Jing Chen Peng Liu Jie Zhao Yufen Zhang Ming Li Dong An | 2009 | Acta Biochimica et Biophysica Sinica2009，41，5： | 7 |
| 11 | Size-dependent elastic properties of thin films: surface anisotropy and surface bonding显示文摘Surface eigenstress and eigendisplacement models were used to investigate the surface stress,surface relaxation and surface elasticity of thin films with different surface orientations.Molecular dynamics simulations and first-principles calculations were conducted on face-centered cubic Au films with the focus on relaxation induced nonlinear initial deformation.The simulation results verify the theoretical predictions of the size dependency of surface energy density and surface stress,and the nonlinear scaling law of the size-dependent Young’s modulus of thin films.The mechanism of the size-dependent behaviors was further explored at the atomic bonding level with the charge density field.The Au atomic bonding at surfaces is enhanced compared to its interior counterpart and therefore the nominal Young’s modulus of the Au thin films is larger when the film thickness is smaller. | ZHOU XiaoYe REN Hang HUANG BaoLing ZHANG TongYi | 2014 | Science China(Technological Sciences)2014，57，4： | 5 |
| 12 | Experimental Study on a Centrifugal Pump with an Open Impeller during Startup Period显示文摘Transient performance of fluid machinery during transient operating periods,such as startup and stopping,has been drawn more attentions recently due to the growing engineering needs.In this paper,the transient behavior of a prototype centrifugal pump with an open impeller during rapid startup period is studied experimentally.The variations of the rotational speed,flow rate,head,and shaft power during rapid startup period are recorded in experiments at different discharge valve openings.In addition,the non-dimensional flow rate and head are also used to analyze the transient behavior.The research result shows that the rise characteristic of the rotational speed is not basically changed by working points,while mainly depends on the startup characteristics of the driving motor.Compared with the rapid rise of the rotational speed,the flow rate rises slowly in the initial stage of startup.Moreover,the flow rate lags behind the rotational speed to rise to final stable value,and the delay becomes more severe with the increase of the discharge valve opening.The shaft power impact phenomenon generally exists in the process of startup.The non-dimensional analysis shows that the non-dimensional head is very high at the very beginning of startup,and quickly falls to the minimum,then gradually rises to final stable value,while the non-dimensional flow rate always shows the rise tendency during whole startup period.In conclusion,it is found from the non-dimensional results that the quasi-steady analysis is unable to accurately assess the transient flow during startup period. | Yuliang Zhang Zuchao Zhu Yingzi Jin Baoling Cui Yi Li Huashu Dou | 2013 | Journal of Thermal Science2013，22，1： | 5 |
| 13 | Laboratory-scale column study for remediation of TCE-contaminated aquifers using three-section controlled-release potassium permanganate barriers显示文摘A laboratory-scale study with a sand column was designed to simulate trichloroethylene(TCE) pollution in the aquifer environment with three-section controlled-release potassium permanganate(CRP) barriers.The main objective of this study was to evaluate the feasibility of CRP barriers in remediation of TCE in aquifers in a long-term and controlled manner.CRP particles with a 1:3 molar ratio of KMnO 4 to stearic acid showed the best controlled-release properties in pure water,and the theoretical release time was 138.5 days.The results of TCE removal in the test column indicated that complete removal efficiency of TCE in a sand column by three-section CRP barriers could be reached within 15 days.The molar ratio of KMnO 4 to TCE in the three-section CRP barriers was 16:1,which was much lower than 82:1 as required when KMnO 4 solution is used directly to achieve complete destruction of TCE.This result revealed that the efficiency of CRP for remediation of TCE was highly improved after encapsulation. | Baoling Yuan Fei Li Yanmei Chen Ming-Lai Fu | 2013 | Journal of Environmental Sciences2013，25，5： | 5 |
| 14 | Anti-cavitation performance of a splitter-bladed inducer under different flow rates and different inlet pressures显示文摘The anti-cavitation performance of a high-speed centrifugal pump with a splitter-bladed inducer is investigated under different flow rates and different inlet pressures. Simulations and external characteristics experiments are carried out. Static pressure and the vapor volume fraction distributions on the inducer and the impeller of the pump under various operation conditions are obtained. The results show that the cavitation developments on the impeller and on the inducer with the flow rates are reverse, while the development of the inlet pressure on the inducer and the impeller is the same. Cavitation on the impeller increases with the increase of flow rates, and it extends to the near passages with rotating, while cavitation on the inducer is more complex than that on the impeller. Cavitation at the inlet of the inducer decreases with the increase of flow rates, while cavitation at the outlet of the inducer is opposite. The results also show that cavitation development on the impeller and on the inducer with the inlet pressure is the same. Cavitation both decreases with the increase of the inlet pressure at the same flow rate. Furthermore, asymmetric cavitation on the impeller and on the inducer is both observed. And the asymmetric degree of cavitation on the impeller is higher than that on the inducer. | GUO XiaoMei ZHU ZuChao CUI BaoLing HUANG Yong | 2015 | Science China(Technological Sciences)2015，58，12： | 4 |
| 15 | Pressure Fluctuation Generated by the Interaction of Blade and Tongue显示文摘Pressure fluctuation around the tongue has large effect on the stable operation of a centrifugal pump. In this paper, the Reynolds averaged Navier-Stokes equations(RANS) and the RNG k-epsilon turbulence model is employed to simulate the flow in a pump. The flow field in the centrifugal pump is computed for a range of flow rate. The simulation results have been compared with the experimental data and good agreement has been achieved. In order to study the interaction of the tongue with the impeller, fifteen monitor probes are evenly distributed circumferentially at three radii around the tongue. Pressure distribution is investigated at various blade positions while the blade approaches to and leaves the tongue region. Results show that pressure signal fluctuates largely around the tongue, and it is more intense near the tongue surface. At design condition, standard deviation of pressure fluctuation is the minimum. At large flow rate, the increased low pressure region at the blade trailing edge results in the increases of pressure fluctuation amplitude and pressure spectra at the monitor probes. Minimum pressure is obtained when the blade is facing to the tongue. It is found that the amplitude of pressure fluctuation strongly depends on the blade positions at large flow rate, and pressure fluctuation is caused by the relative movement between blades and tongue. At small flow rate, the rule of pressure fluctuation is mainly depending on the structure of vortex flow at blade passage exit besides the influence from the relative position between the blade and the tongue. | ZHENG Lulu DOU Hua-Shu CHEN Xiaoping ZHU Zuchao CUI Baoling | 2018 | Journal of Thermal Science2018，27，1： | 4 |
| 16 | Factors Affecting Small Axial Cooling Fan Performance显示文摘Many factors such as outer diameter,hub ratio,blade numbers,shape and stagger angle affect the performance of small cooling fans.A small cooling fan was simulated using CFD software for three blade stagger angles (30.5°,37.5°,44.5°)and obtained the internal flow field and the static characteristics.Research indicated that the stagger angle has an obvious effect on the static characteristics of a fan.For flow rates below 0.0104 m3/s,total pressure is the greatest when the stagger angle is 37.5°;flow rates higher than 0.0104 m3/s,the total pressure is greatest when the stagger angle is 44.5° For the same flow rates,the velocity at inlet of pressure surface increases with increasing stagger angle,but the change of velocity on the suction surface is very small.For one model,vortices and the speed of revolution surfaces decrease with tip clearance increasing.But for other three models,increasing the stagger angle,the vortex intensity and speed of revolution surfaces at same height tip clearance increases,simultaneously,the position of vortex offset from the top of the rotor blade to the suction surface. | Lihong Wang,Yingzi Jin,Baoling Cui,Yuzhen Jin,Jin Lin,Yanping Wang and Chuanyu Wu College of Mechanical Engineering & Automation,Zhejiang Sci-Tech University,Xiasha Education Zone,Hangzhou 310018,China | 2010 | Journal of Thermal Science2010，19，2： | 4 |
| 17 | Safety and efficacy of Yupingfeng granules in children with recurrent respiratory tract infection:A randomized clinical trial显示文摘Importance:Recurrent respiratory tract infection(RRTI)is common in children.Inappropriate RRTI treatment will lead to asthma and other diseases,thereby seriously affecting the growth and physical health of children.Immune function modulation can prevent and alleviate childhood RRTI.Yupingfeng(YPF),a patented traditional Chinese medicine(TCM),has immunomodulatory effects and is widely used in China to treat children with RRTI.Objective:To evaluate the safety and efficacy of YPF monotherapy in treating children with RRTI.Methods:This multicenter,randomized,double-blind,double-simulation,noninferiority clinical trial was conducted from January 2015 to August 2017,with an 8-week treatment period and 52-week follow-up after the drug withdrawal.Children aged 2–6 years with RRTI meeting the inclusion and exclusion criteria were enrolled in 13 hospitals in China and divided randomly into three groups(2:2:1 ratio)to receive YPF,pidotimod,or placebo.The primary outcome was the proportion of RRTI returning to normal standard level during the follow-up.The secondary outcomes were reduction in the number of RRTI recurrences,effect on clinical symptoms(in accord with TCM practice),effect per symptom,and safety.The trial was registered at the Chinese Clinical Trials Registry(www.chictr.org.cn)under the unique identifier ChiCTR-IPR-15006847.Results:Three hundred and fifty-one children were enrolled and randomly assigned to 3 groups;124,125,and 61 children in the YPF,pidotimod,and placebo groups,respectively,had completed the trial.During the follow-up,the proportion of RRTI returning to normal standard level was 73.13%,67.15%,and 38.81%with YPF,pidotimod,and placebo,respectively(P<0.0001).The proportion of cases who returned to normal standard level in the YPF group was 34.32%higher than that in the placebo group.The safety profile did not significantly differ among the groups.Interpretation:YPF granules were noninferior to the active control drug pidotimod oral solution for the treatment of RRTI in children,and were superior to placebo,with a high safety profile. | Baoping Xu Xinmin Li Siyuan Hu Yixiao Bao Fengmei Chen Zhimin Chen Yonggang Du Enmei Liu Yufeng Liu Qinghui Mou Baoling Su Bo Wang Jianwen Xu Guiping Xu Qiaozhi Yang Liwei Gao Xiaohui Liu Lei Li Rong Ma Kunling Shen | 2022 | Pediatric Investigation2022，6，2： | 3 |
| 18 | A rhizobia strain isolated from root nodule of gymno-sperm Podocarpus macrophyllus显示文摘Symbiotic nitrogen fixation of rhizobia and leguminous plants is considered as the most important biologic nitrogen fixation system on earth. Symbiotic nodulation of gymnosperm Podocarpus macro-phyllus and rhizobia has never been reported. In this study, 11 endophytic bacteria strains were isolated from root nodules of P. macrophyllus and its variation P. macrophyllus var. maki. The plant infection tests on these strains indicated that the isolated strains could be nodulated on P. macrophyllus plants, and weak nitrogenase activity of nodules was found in acetylene reduction method. According to the physiological and biochemical characteristics of the 11 strains, GXLO 02 was selected as the representative strain. 16S rDNA full-length sequence analysis of GXLO 02 confirmed that the representative strain GXLO 02 belongs to Rhizobium sp. | HUANG BaoLing, LU ChengQun, WU Bo & FAN LiQin 1 Forestry College, Guangxi University, Nanning 530004, China 2 Guangxi Key Laboratory of Subtropical Bioresource Conservation and Utilization, Nanning 530004, China | 2007 | Science China(Life Sciences)2007，50，2： | 3 |
| 19 | Influence of Blade Outlet Angle on Performance of Low-specific-speed Centrifugal Pump显示文摘In order to analyze the influence of blade outlet angle on inner flow field and performance of low-specific-speed centrifugal pump, the flow field in the pump with different blade outlet angles 32.5°and 39° was numerically calculated. The external performance experiment was also carried out on the pump. Based on SIMPLEC algorithm, time-average N-S equation and the rectified k-ε turbulent model were adopted during the process of computation. The distributions of velocity and pressure in pumps with different blade outlet angles were obtained by calculation. The numerical results show that backflow areas exist in the two impellers, while the inner flow has a little improvement in the impeller with larger blade outlet angle. Blade outlet angle has a certain influence on the static pressure near the long-blade leading edge and tongue, but it has little influence on the distribution of static pressure in the passages of impeller. The experiment results show that the low-specific-speed centrifugal pump with larger blade outlet angle has better hydraulic performance. | Cui Baoling Wang Canfei Zhu Zuchao Jin Yingzi | 2013 | Journal of Thermal Science2013，22，2： | 3 |
| 20 | Numerical simulation of the effect of upstream swirling flow on swirl meter performance显示文摘Flow measurement is important in the fluid process and transmission system. For the need of accuracy measurement of fluid, stable flow is acquired. However, the elbows and devices as valves and rotary machines may produce swirling flow in the natural gas pipeline networks system and many other industry fields. In order to reveal the influence of upstream swirling flow on internal flow fields and the metrological characteristics, numerical simulations are carried out on the swirl meter. Using RNG k-ε turbulent model and SIMPLE algorithm, the flow field is numerically simulated under swirling flows generated from co-swirl and counter-swirl flow. Simulation results show fluctuation is enhanced or weakened depending on the rotating direction of swirling flow. A counter-swirl flow increases the entropy production rate at the inlet and outlet of the swirler, the junction region between throat and divergent section, and then the pressure loss is increased. The vortex precession dominates the static pressure distributions on the solid walls and in the channel, especially at the end region of the throat. | CHEN Desheng CUI Baoling ZHU Zuchao | 2018 | Journal of Thermal Science2018，27，2： | 3 |
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