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氮、磷、钾配施对葛根生长及品质的影响

中国土壤与肥料 2024年第4期 153-158页

作者：彭斯文戴翠婷谢进徐瑞彭正明龙世平湖南省农业科学院湖南长沙410125 武陵源区协合乡经济发展综合服务中心湖南张家界427499

为探明氮、磷、钾肥配施对葛根生长及品质的影响,为葛根高效栽培提供合理的施肥技术支撑和理论依据,采用L_(9)(3~4)正交试验设计,研究氮、磷、钾配施对葛根产量和主要功能成分的影响,明确研究区葛根氮、磷、钾的最佳施用量。结果表明,... 详细信息

为探明氮、磷、钾肥配施对葛根生长及品质的影响,为葛根高效栽培提供合理的施肥技术支撑和理论依据,采用L_(9)(3~4)正交试验设计,研究氮、磷、钾配施对葛根产量和主要功能成分的影响,明确研究区葛根氮、磷、钾的最佳施用量。结果表明,不同施肥方案对葛根产量和功能成分的影响显著,其中以N_(3)P_(1)K_(2)(N 270kg/hm^(2),P_(2)O_(5)45 kg/hm^(2),K_(2)O 90 kg/hm^(2))处理的产量和总黄酮含量最高,分别为2.13 kg/株和83.10 mg/g;N_(1)P_(3)K_(2)(N 90 kg/hm^(2),P_(2)O_(5)135 kg/hm^(2),K_(2)O 90 kg/hm^(2))的葛根素含量最高,为24.85 mg/g,N_(1)P_(2)K_(3)(N 90 kg/hm^(2),P_(2)O_(5)90 kg/hm^(2),K_(2)O 135 kg/hm^(2))处理的大豆苷和大豆苷元含量均为最高,分别为22.96和2.55 mg/g。氮、磷、钾肥配施对葛根产量和葛根素含量影响的大小顺序为氮肥>钾肥>磷肥。以葛根产量为目标的最佳施肥量为N 270 kg/hm^(2)、P_(2)O_(5)135 kg/hm^(2)、K_(2)O 90 kg/hm^(2),以葛根品质提升为目标的最佳施肥量为N 180 kg/hm^(2)、P_(2)O_(5)135 kg/hm^(2)、K_(2)O 90 kg/hm^(2)。

关键词：葛根氮磷钾配施产量功能成分

Experimental and Internal Flow Investigation on the Performance of a Hydraulic Retarder with Different Liquid-Filled Amount and Blade Inclination Angles

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Journal of Thermal Science 2022年第3期31卷 923-933页

作者： dai cui DONG Liang ZHANG Xing ZHU Jiancheng LIN Haibo School of Energy and Power Engineering Jiangsu UniversityZhenjiang212013China Sichuan Provincial Key Lab of Process Equipment and Control Sichuan University of Science&EngineeringZigong643000China Research Center of Fluid Machinery Engineering and Technology Jiangsu UniversityZhenjiang212013China Pipeline Research Design Center PipeChina North Pipeline CompanyLangfang065000China

In order to study the variation of brake torque,vibration,pressure fluctuation,exterior noise and internal flow for a hydraulic retarder with different inclination angles and liquid-filled amount,a bench-scale hydraulic retarder was *** INV3020 data collection system was used for the synchronous acquisition of brake torque,vibration,pressure fluctuation and exterior noise *** were performed with different inclination angles(90°and 75°)and six liquid-filled amount(50 vol%,60 vol%,70 vol%,80 vol%,90vol%and 100 vol%).The torque-volume ratio was proposed to accurately analyze the influence of inclination angle on the liquid volume in stator and rotor and the brake *** multiphase flow model was employed to capture the volume and velocity *** research shows that the brake performance improves and the vibration increases with the decrease of inclination angle and the increase of liquid-filled *** pressure fluctuation increases as the liquid-filled amount increases,while the lower inclination angle effectively lowers the pressure fluctuation *** sound pressure level trends upward with increasing liquid-filled amount,and the lower inclination angle can effectively reduce the *** volume distribution of the liquid phase under different liquid-filled amount is basically *** lower inclination angle can induce more vortexes.

关键词： hydraulic retarder blade inclination angle liquid-filled amount brake torque vibration pressure fluctuation noise numerical calculation

国际标准化超细针穿刺甲状腺结节不同细胞学采集模式诊断率的比较

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南京医科大学学报（自然科学版） 2024年第1期44卷 45-51页

作者：谷志远王知笑蔡赟崔岱陈欢欢戎荣杨涛刘晓云南京医科大学第一附属医院内分泌科江苏南京210029 南京大学医学院附属鼓楼医院内分泌科江苏南京210008 南京医科大学第一附属医院病理科江苏南京210029

目的:评价甲状腺结节穿刺时不同留样顺序对细胞学诊断率的影响。方法:共入选591例甲状腺结节患者的613个甲状腺结节,所有甲状腺结节均行4针细针穿刺,分为两种模式进行。模式一:304个结节穿刺,前2针进行涂片细胞学检查,后2针再进行液基... 详细信息

目的:评价甲状腺结节穿刺时不同留样顺序对细胞学诊断率的影响。方法:共入选591例甲状腺结节患者的613个甲状腺结节,所有甲状腺结节均行4针细针穿刺,分为两种模式进行。模式一:304个结节穿刺,前2针进行涂片细胞学检查,后2针再进行液基细胞学检查;模式二:309个结节穿刺,前2针进行液基细胞学检查,后2针再进行传统涂片细胞学制片。细胞病理医师采用盲法单独对每份样本进行读片。比较不同细胞学制片方法以及两种模式对细针穿刺诊断率的影响。结果:先液基后涂片的细胞学采集模式总体诊断率为82.2%,显著高于先涂片后液基的模式(74.7%)(P=0.023)。对于直径≥10 mm的结节来说,先液基后涂片的细胞学采集模式总体诊断率为83.2%,同样显著高于先涂片后液基模式的诊断率(75.4%)(P=0.048);同为前2针,单独液基方法诊断率为78.0%,显著高于单独涂片诊断率(63.8%)(P<0.001);对于直径≥10 mm的结节而言,单独液基诊断率为78.3%,亦显著高于单独涂片的诊断率(62.6%)(P<0.001)。结论:使用国际标准化超细针进行甲状腺细针穿刺,先液基再涂片的细胞学采集模式诊断率显著高于先涂片后液基的采集模式;如果仅以一种方式来收取细胞学标本,沉降式液基细胞采集制片的方法诊断率显著优于传统涂片制片方法。

关键词：甲状腺细针穿刺甲状腺结节涂片细胞学液基细胞学

UPLC-Q-TOF-MS/MS法分析紫辛鼻鼽颗粒化学成分及入血成分

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中成药 2024年第4期46卷 1093-1102页

作者：康雨胡军华章晨峰肖伟戴翠红林夏王振中南京中医药大学江苏南京210000 江苏康缘药业股份有限公司中药制药过程控制与智能制造技术全国重点实验室江苏连云港222001

目的建立UPLC-Q-TOF-MS/MS法分析紫辛鼻鼽颗粒化学成分及入血成分。方法分析采用Agilent ZORBAX SB-C_(18)色谱柱(1.8μm, 2.1 mm×100 mm);流动相0.2%甲酸-乙腈,梯度洗脱;体积流量0.2 mL/min;柱温30℃;电喷雾离子源;正负离子扫描。... 详细信息

目的建立UPLC-Q-TOF-MS/MS法分析紫辛鼻鼽颗粒化学成分及入血成分。方法分析采用Agilent ZORBAX SB-C_(18)色谱柱(1.8μm, 2.1 mm×100 mm);流动相0.2%甲酸-乙腈,梯度洗脱;体积流量0.2 mL/min;柱温30℃;电喷雾离子源;正负离子扫描。根据准分子离子、保留时间、二级碎片离子结合对照品信息及文献报道进行成分鉴定。结果共鉴定出88种成分,其中28种经对照品比对确认。从大鼠血清中发现了30种成分,其中20种为原型成分,10种为代谢产物。结论该方法稳定可靠,可为紫辛鼻鼽颗粒药效物质基础、质量控制研究奠定基础。

关键词：紫辛鼻鼽颗粒化学成分入血成分 UPLC-Q-TOF-MS/MS

Induced noise of impeller stuck and passive rotation state in multi-stage pump without power drive under natural flow conditions

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Journal of Hydrodynamics 2023年第5期35卷 1008-1026页

作者： Run-ze Zhou Hou-lin Liu Ru-nan Hua Liang Dong Kim Tiow Ooi cui dai Si-yuan Hu Research Center of Fluid Machinery Engineering and Technology Jiangsu UniversityZhenjiang212013China National Research Center of Pumps Jiangsu UniversityZhenjiang212013China School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingaporeSingapore Wuhan Second Ship Design and Research Institute Wuhan430060China School of Energy and Power Engineering Jiangsu UniversityZhenjiang212013China

The natural flow cooling strategy is commonly employed in modern high-speed vessels and nuclear-powered submarines. These vessels rely on the energy generated by their own speed to drive the cooling system and supply cooling water to the condenser. The circulating pump, which operates without a motor drive under natural flow conditions, is a large resistance component in the cooling system. However, it is also the primary noise source, significantly impacting the vessel’s safe operation and acoustic stealth performance. This study investigates the induced noise characteristics of a multi-stage pump under natural flow conditions by experiment, computational fluid dynamics (CFD), and acoustic finite element method. The analysis encompasses the distribution of the flow field, variations in acoustic power, spectral features of flow-induced noise, and directivity of external field radiation noise under different natural flow conditions. The results show that the acoustic power distribution is correlated with the flow field. When the impeller is stuck, the noise sources primarily concentrate in the flow separation area at the blade’s leading edge, the interface area between the impeller and the guide vane, and the flow shock area inside the guide vane. Conversely, when the impeller rotates passively, the blade wake area has a higher acoustic power. The flow noise spectrum under natural flow conditions mainly exhibits broadband and discrete characteristics. Additionally, the pump structure influences the external field radiation noise, and its directivity varies with different flow rates and characteristic frequencies. This study provides valuable insights into optimal design to reduce the noise of the circulating pump in the vessel’s natural flow cooling system. It is essential for ensuring the safe operation and acoustic stealth performance of high-speed vessels and nuclear-powered submarines.

关键词： Natural flow condition multi-stage pump flow induced noise acoustic power radiation noise directivity

Continuous-Time Channel Prediction Based on Tensor Neural Ordinary Differential Equation

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China Communications 2024年第1期21卷 163-174页

作者： Mingyao cui Hao Jiang Yuhao Chen Yang Du Linglong dai The Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Huawei Technology Co. Ltd.Chengdu Research InstituteChengdu 611730China

Channel prediction is critical to address the channel aging issue in mobile *** channel prediction techniques are mainly designed for discrete channel prediction,which can only predict the future channel in a fixed time slot per frame,while the other intra-frame channels are usually recovered by ***,these approaches suffer from a serious interpolation loss,especially for mobile millimeter-wave *** solve this challenging problem,we propose a tensor neural ordinary differential equation(TN-ODE)based continuous-time channel prediction scheme to realize the direct prediction of intra-frame ***,inspired by the recently developed continuous mapping model named neural ODE in the field of machine learning,we first utilize the neural ODE model to predict future continuous-time *** improve the channel prediction accuracy and reduce computational complexity,we then propose the TN-ODE scheme to learn the structural characteristics of the high-dimensional channel by low-dimensional learnable *** results show that the proposed scheme is able to achieve higher intra-frame channel prediction accuracy than existing schemes.

关键词： channel prediction massive multipleinput-multiple-output millimeter-wave communications ordinary differential equation

Soil bacterial and fungal communities resilience to long-term nitrogen addition in subtropical forests in China

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Journal of Forestry Research 2024年第2期35卷 95-108页

作者： Xinlei Fu Yunze dai Jun cui Pengfei Deng Wei Fan Xiaoniu Xu School of Forestry and Landscape Architecture Anhui Agricultural UniversityHefei 230036AnhuiPeople’s Republic of China Suzhou Polytechnic Institute of Agriculture Suzhou 215008JiangsuPeople’s Republic of China College of Life and Environment Sciences Huangshan UniversityHuangshan 245041AnhuiPeople’s Republic of China

Atmospheric nitrogen(N)deposition is predicted to increase,especially in the ***,the responses of soil microorganisms to long-term N addition at the molecular level in N-rich subtropical forests have not been clarified.A long-term nutrient addition experiment was conducted in a subtropical evergreen old-growth forest in *** four treatments were:control,low N(50 kg N ha^(-1)a^(-1)),high N(100 kg N ha^(-1)a^(-1)),and combined N and phosphorus(P)(100 kg N ha^(-1)a^(-1)+50 kg P ha^(-1)a^(-1)).Metagenomic sequencing characterized diversity and composition of soil microbial communities and used to construct bacterial/fungal co-occurrence ***-treated soils were more acidic and had higher levels of dissolved organic carbon than *** were no significant differences in microbial diversity and community composition across *** addition of nutrients increased the abundance of copiotrophic bacteria and potentially beneficial microorganisms(e.g.,Gemmatimonadetes,Chaetomium,and Aureobasidium).Low N addition increased microbiome network *** rare fungi were identified as module hubs under nutrient addition,indicating that low abundance fungi were more sensitive to increased *** results indicate that the overall composition of microbial communities was stable but not static to long-term N *** findings provide new insights that can aid predictions of the response of soil microbial communities to long-term N addition.

关键词： Long-term nitrogen addition Old-growth subtropical forest Metagenomics Beneficial microorganisms Co-occurrence network

Influence of Flap Parameters on the Aerodynamic Performance of a Wind-Turbine Airfoil

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Fluid Dynamics & Materials Processing 2024年第4期20卷 771-786页

作者： Yuanjun dai Jingan cui Baohua Li Cong Wang Kunju Shi Mechanical College Shanghai DianJi UniversityShanghai201306China College of Energy Engineering Xinjiang Institute of TechnologyUrumqi830091China

A numerical method has been used to analyze the flow field related to a NACA 0015 airfoil with and without a flap and assess the influence of the flap height and angle on the surface pressure coefficient,lift coefficient,and drag *** numerical results demonstrate that the flap can effectively improve the lift coefficient of the airfoil;however,at small attack angles,its influence is significantly *** the angle of attack exceeds the critical stall angle and the flap height is 1.5%of the chord length,the influence of the flap becomes very *** the flap height increases,the starting point of the separation vortex gradually moves forward and generates a larger wake *** aerodynamic characteristics are obtained for 1.5%(of the chord length)flap height and a 45°flap angle;in this case,the separation vortex is effectively reduced.

关键词： Airfoil flap height flap angle lift-drag ratio aerodynamic characteristics

A Hydraulic Performance Comparison of Centrifugal Pump Operating in Pump and Turbine Modes

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Journal of Thermal Science 2020年第6期29卷 1594-1605页

作者： dai cui DONG Liang LIN Haibo ZHAO Fei School of Energy and Power Engineering Jiangsu UniversityZhenjiang 212013China Sichuan Provincial Key Lab of Process Equipment and Control Sichuan University of Science&EngineeringZigong 643000China Research Center of Fluid Machinery Engineering and Technology Jiangsu UniversityZhenjiang 212013China School of Mechanical Research Center of Technology Wuxi Institute of TechnologyWuxi 214121China

The modifications of impeller may show diverse impact on centrifugal pump operating in pump and turbine *** clarify this problem,the hydraulic performance of a low specific speed centrifugal pump operating in both modes was firstly obtained by CFD method and verified by ***,based on the single-factor design method,a series of calculations have been conducted to identify the effects of impeller geometry parameters on the hydraulic performance in different *** variations of head,shaft power and hydraulic efficiency curves with different impeller parameters were *** is found that compared with turbine,the pump shows a more obvious variation of *** outlet angle has positive impact both on the head consumed by pump or generated by *** change of turbine shaft power is apparently smaller than that of pump for different impeller geometry *** the outlet width somewhat changes the turbine shaft *** hydraulic efficiency in both modes shows different variation under different impeller geometric parameters,while the hydraulic efficiency of both modes is reduced with the outlet angle ***,the response amount of hydraulic efficiency caused by certain change of impeller parameters was estimated by sensitivity analysis *** is found that only the appropriate blade number and outlet width can improve the hydraulic performance both in pump and turbine ***,the hydraulic loss,skin friction loss and theoretical analysis were performed to explore the reason of hydraulic performance variation due to different impeller *** change of slip factor,impeller inlet area,impeller outlet area or hydraulic loss results in the change of hydraulic performance in both *** results can be useful for hydraulic performance improvement for both pump and turbine modes through impeller geometry modification.

关键词： Computational Fluid Dynamics centrifugal pump impeller modification pump mode turbine mode