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Research Status, Critical Technologies, and Development Trends of Hydraulic Pressure Pulsation Attenuator

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Chinese Journal of Mechanical Engineering 2021年第1期34卷 114-130页

作者： Yan Wang Tongsheng Shen Chunsen Tan Jian Fu shengrong guo School of Transportation Science and Engineering Beihang UniversityBeijing 100083China School of Mechanical Engineering and Automation Beihang UniversityBeijing 100083China Nanjing Engineer Institute of Air-craft Systerm Jincheng AVICNanjing 211100China

Hydraulic pumps are a positive displacement pump whose working principle causes inherent output flow pulsation.Flow pulsation produces pressure pulsation when encountering liquid resistance.Pressure pulsation spreads in the pipeline and causes vibration,noise,damage,and even pipeline rupture and major safety accidents.With the development of airborne hydraulic systems with high pressure,power,and flow rate,the hazards of vibration and noise caused by pressure pulsation are also amplified,severely restricting the application and development of hydraulic systems.In this review paper,the mechanism,harm,and suppression method of pressure pulsation in hydraulic systems are analyzed.Then,the classification and characteristics of pulsation attenuators according to different working principles are described.Furthermore,the critical technology of simulation design,matching method with airborne piston pumps,and preliminary design method of pulsation attenuators are proposed.Finally,the development trend of pulsation attenuators is prospected.This paper provides a reference for the research and application of pressure pulsation attenuators.

关键词： Hydraulic pump Pressure pulsation Pulsation attenuator

Hydraulic piston pump in civil aircraft: Current status, future directions and critical technologies

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Chinese Journal of Aeronautics 2020年第1期33卷 16-30页

作者： shengrong guo Jinhua CHEN Yueliang LU Yan WANG Hongkang DONG Nanjing Engineer Institute of Aircraft System Jincheng AVICNanjing 211100China Aviation Science and Technology Key Laboratory of Aero Electromechanical System Integration Nanjing 211100China School of Transportation Science and Engineering Beihang UniversityBeijing 100083China

The piston pump is the key power component in the civil aircraft hydraulic system,and the most common pump used in the aviation field is the pressure compensated variable displacement type.In this review paper,a basic introduction to the civil aircraft piston pump is presented,including the classification,structure,working principle,design features,and achievements by some research groups.Then,the future directions of the aircraft pump are reported from various perspectives.Further,the critical technologies are analyzed and summarized in detail from six thrust areas:friction couples,noise reduction,inlet boost,thermal management,fault diagnosis and health management,and mechanical seal.Finally,the challenges and limitations of the research on the aircraft pump are discussed to provide valuable insight for future scholars.

关键词： Civil aircraft Engine driven pump High pressure Inlet boost Intelligent control Lubricating gaps Piston pumps Pulsation reduction

双权变指标Herz-Morrey空间上的双线性Calderón-Zygmund算子的交换子

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应用数学 2024年第2期37卷 337-358页

作者：王盛荣郭鹏飞徐景实海南师范大学数学与统计学院海南海口571158 桂林电子科技大学数学与计算科学学院广西桂林541004

利用Muckenhoupt权的性质、有界平均振荡函数的性质和Hardy-Littlewood极大算子在变指标Lebesgue空间上的有界性,本文得到了双线性Calderón-Zygmund算子和BMO函数生成的交换子在双权变指标Herz-Morrey空间乘积上的有界性.

关键词： Calderón-Zygmund算子 Muckenhoupt权变指标 Herz-Morrey空间

Reasonable location of stopping line in close‑distance underlying coal seam and partition support of large cross‑section roadway

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International Journal of Coal Science & Technology 2022年第4期9卷 181-202页

作者： Dongdong Chen Yiyi Wu shengrong Xie Fangfang guo Fulian He Ruipeng Liu School of Energy and Mining Engineering China University of Mining&Technology-BeijingBeijing 100083China

Close-distance coal seams are widely distributed over China,and the coal pillars left by the overlying coal seams afect the retracement channel of the underlying coal seam in the stopping stage.Based on the engineering background of close-distance seam mining in a coal mine,the reasonable position of the underlying coal seam's stopping line and the support method of the large section roadway during stopping are investigated using feld measurements,similar simulation experiments,and numerical simulations.There are three types of location relationships between the stopping line of the underlying coal seam and the stopping line of the overlying coal seam:"externally staggered with the upper stopping line"(ESUL,stops mining under the overlying goaf),"overlapped with upper stopping line"(OUL),and"internally staggered with the upper stopping line"(ISUL,ISUL-SD for shorter internal staggered distances,ISUL-LD for longer ones).There are diferent stress arch structures in the overlying strata of the above three positions,and the stress arch evolution process exists in the process of ESUL→OUL→ISUL-SD→ISUL-LD:a front and rear double stress arch structure→the front arch gradually decreases→the front arch dies out,and the double arch synthesizes the single arch→the single-arch range expands→the nested double arch.The relationship between the stress arch structure and the position of the stopping line is evaluated as follows:(1)ESUL:the stress concentration in the roof plate of the retracement channel of the underlying coal seam is the highest,because the overburden block of the extensive collapse zone acts directly on the roof plate of the retracement channel,resulting in relative difculties in roof support.(2)OUL:although the retracement channel roof pressure is minimal,the overlying rock structure has the potential for rotation or slippage instability.(3)ISUL-SD:the pressure on the roof of the retracement channel is small and the overburden structure is stable,which is conducive to the safe retraction of the support and not

关键词： Close-distance coal seams Stopping line Stress arch structure Retracement channel Partition support

Significant effects of transport on nanoparticles during new particle formation events in the atmosphere of Beijing

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Particuology 2023年第9期80卷 1-10页

作者： Dongjie Shang Min Hu Lizi Tang Xin Fang Ying Liu Yusheng Wu Zhuofei Du Xuhui Cai Zhijun Wu shengrong Lou Mattias Hallquist Song guo Yuanhang Zhang State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringInternational JointLaboratory for Regional Pollution ControlMinistry of Education(IJRC)Peking UniversityBeijing100871China Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Nanjing University of Information Science&TechnologyNanjing210044China Department of Chemistry and Molecular Biology University of GothenburgGothenburg41296Sweden Shanghai Academy of Environmental Sciences Shanghai200233China

The mechanisms of new particle formation(NPF)events that occurred under high aerosol loadings(“polluted”NPF)in the atmosphere have been unclear,which has inhibited the precision of particlepollution control.To deepen the understanding of how the“polluted”NPF events occur,a one-monthcomprehensive measurement was conducted in the atmosphere of Beijing during the summer of2016.The“clean”NPF events(frequency=22%)(condensation sink,CS0.015 s^(-1))were influenced by both local nucleation-growth and regional transport,and the contributions from thetwo factors to 6e25 nm particle number concentration were 60%and 40%,respectively.This studyemphasized the importance of the transport for nanoparticles in relatively polluted atmospheres,and forthat the regional joint particle pollution control would be an essential policy.

关键词： New particle formation Transport Nanoparticles Sulfuric acid

A CODING SCHEME USING GLOBAL MOTION ESTIMATION FOR AVS P-FRAME

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Journal of Electronics(China) 2007年第6期24卷 815-820页

作者： Gong shengrong guo Li Cui Zhiming School of Computer Science and Technology Soochow University Suzhou 215006 China

Block matching has been used for motion estimation and motion compensation in the Au- dio and Video Standard (AVS) for years. While having an acceptable performance in describing mo- tion between frames, it requires quite a few bits to represent the motion vectors. In certain circum- stances, the use of global motion estimation and compensation would perform equally well or even better than the block matching in terms of motion accuracy, while it results in the coding of global motion model parameters. In this letter, we modify an AVS coder by adding (1) six global motion model parameters to the frame header, and (2) mode selection among INTRA, SKIP, INTER-16×16, INTER-16×8, INTER-8×16, INTER-8×8, and Global Motion Compensation (GMC) modes by La- grange optimal rate-distortion criteria. Simulation results demonstrate that over 0.1dB improvement in PSNR is obtained compared to the AVS coder for an average coded P-frame with the same bit- rate.

关键词：计算机技术设计方案通信技术网络

UV-resistant salicylic acid as interface modifier for efficient and stable perovskite solar cells

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Chinese Journal of Structural Chemistry 2023年第6期42卷 36-40页

作者： guo-Bin Xiao Zihan Fang shengrong Yang Jing Cao Yu Tang Laboratory of Clean Energy Chemistry and Materials State Key Laboratory of Solid LubricationLanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000PR China State Key Laboratory of Applied Organic Chemistry Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu ProvinceCollege of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou730000PR China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049PR China

Interfacial defect is one of the main hurdles to impede the improvement of efficiency and stability of perovskite solar cells(PSCs).Additionally,the ultraviolet(UV)irradiate induces the generation of deep defects,and further accelerate the decomposition of perovskite films.Thus,the interfacial modification is crucial to improve the ef-ficiency and stability of PSCs.Here,the salicylic acid(SA)as a multifunctional interface material is employed to modify the interface of mesoporous cerium oxide(m-CeO_(x))and perovskite.The introduced SA molecules can interact with Ce in m-CeO_(x)and Pb in perovskite through carboxylic acid functional groups to passivate interfacial defects and promote interfacial electron extraction and transport.The PSC with SA modification exhibits an improved power conversion efficiency(PCE)of 23.33%.More importantly,the SA can absorb UV light and reduce the damage of UV light to perovskite film,then improving the UV stability and overall stability of devices.This work provides a novel insight to design the interfacial modification materials for preparing efficient and stable PSCs.

关键词： Salicylic acid Interface modification UV absorption Perovskite solar cells

Intracellularly Degradable,Self-assembled Amphiphilic Block Copolycurcumin Nanoparticles for Efficient in vivo Cancer Chemotherapy

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Intracellularly Degradable,Self-assembled Amphiphilic Block ...

Size-resolved effective density of submicron particles during summertime in the rural atmosphere of Beijing, China

2016年广东省药师周大会

作者：吕立 Yuan guo Yuanyuan Shen Jieying Liu Wenjun Zhang Dejian Zhou shengrong guo 中山大学孙逸仙纪念医院药学部

Chemotherapy is widely used in various cancer treatments.However,current cancer chemotherapy has a major limitation:lacking of specific targeting ability.As a result,it kills both cancerous and healthy cells,causing severe adverse side-effects and toxicity to patients which limits the dose regime and allows tumour to gain resistance.One approach to address

关键词： nanoparticles self assembly drug delivery cancer therapy curcumin

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Journal of Environmental Sciences 2018年第11期30卷 69-77页

作者： Kai Qiao Zhijun Wu Xiangyu Pei Qianyun Liu Dongjie Shang Jing Zheng Zhuofei Du Wenfei Zhu Yusheng Wu shengrong Lou Song guo Chak K.Chan Ravi Kant Pathak Mattias Hallquist Min Hu State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University Beijing 100871 China Atmospheric Science Department of Chemistry and Molecular Biology University of Gothenburg Gothenburg 412 96 Sweden Division of Environment and Sustainability Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong China Shanghai Academy of Environmental Sciences Shanghai 200233 China School of Energy and Environment City University of Hong Kong Tat Chee Avenue Kowloon Hong Kong China

Particle density is an important physical property of atmospheric particles. The information on high time-resolution size-resolved particle density is essential for understanding the atmospheric physical and chemical aging processes of aerosols particles. In the present study, a centrifugal particle mass analyzer （CPMA） combined with a differential mobility analyzer （DMA） was deployed to determine the size-resolved effective density of 50 to 350 nm particles at a rural site of Beijing during summer 2016. The measured particle effective densities decreased with increasing particle sizes and ranged from 1.43 to 1.55 g/cm3, on average. The effective particle density distributions were dominated by a mode peaked at around 1.5 g/cm3 for 50 to 350 nm particles. Extra modes with peaks at 1.0, 0.8, and 0.6 g/cm3 for 150, 240, and 350 nm particles, which might be freshly emitted soot particles, were observed during intensive primary emissions episodes. The particle effective densities showed a diurnal variation pattern, with higher values during daytime. A case study showed that the effective density of Aitken mode particles during the new particle formation （NPF） event decreased considerably, indicating the significant contribution of organics to new particle growth.

关键词： Effective density Atmospheric aerosol Centrifugal particle mass analyzer Rural site New particle formation