When designing a complex pipeline with long distance and multi-supports for offshore platform,it is necessary to analyze the vibration characteristics of the complex pipeline system to ensure that there is no harmful ...When designing a complex pipeline with long distance and multi-supports for offshore platform,it is necessary to analyze the vibration characteristics of the complex pipeline system to ensure that there is no harmful resonance in the working conditions.Therefore,the optimal layout of support is an effective method to reduce the vibration response of hydraulic pipeline system.In this paper,a developed dynamic optimization method for the complex pipeline is proposed to investigate the vibration characteristics of complex pipeline with multi-elastic supports.In this method,the Kriging response surface model between the support position and pipeline is established.The position of the clamp in the model is parameterized and the optimal solution of performance index is obtained by genetic algorithm.The number of clamps and the interval between clamps are considered as the constraints of layout optimization,and the optimization objective is the natural frequencies of pipeline.Taking a typical offshore pipeline as example to demonstrate the effectiveness of the proposed method,the results show that the vibration performance of the hydraulic pipeline system is distinctly improved by the optimization procedure,which can provide reasonable guidance for the design of complex hydraulic pipeline system.展开更多
Nicotinamide adenine dinucleotide (NAD+/NADH) pools homeostasis is recognized as an Achilles’ Heel in tumor metabolism reprogramming. However, mitochondria can enable cancer cells to overcome NADH exhaustion by provi...Nicotinamide adenine dinucleotide (NAD+/NADH) pools homeostasis is recognized as an Achilles’ Heel in tumor metabolism reprogramming. However, mitochondria can enable cancer cells to overcome NADH exhaustion by providing NAD+ precursors and/or intermediates, thus promoting their survival rate and potentially driving uncontrollable proliferation. Here, a synergistic intervention NAD+/NADH homeostasis and mitochondrial metabolism strategy with magnetic resonance imaging (MRI)/photoacoustic imaging (PAI) are developed to address grand challenge of metabolic reprogramming for antitumor bioenergetic therapy. A mitochondrial-targeted cascade amplification nanoplatform ([β-MQ]TRL), triggered by NAD(P)H: quinone oxidoreductase-1 (NQO1), can enable a continuous depletion of cytosol NADH until cell death. The end-product, hydrogen peroxide (H_(2)O_(2)), can be further catalytically converted to higher toxic ·OH in proximity to mitochondria based on [β-MQ]TRL mediated Fenton-like reaction, hijacking tumorigenic energy sources and leading to mitochondrial dysfunction. Additionally, the mild thermal ablation enabled by [β-MQ]TRL further amplifies this cascade reaction to effectively prevent tumor metastasis and recurrence. This synchronous intervention strategy with MRI/PAI establishes unprecedented efficiency in antitumor bioenergetic therapy in vivo, which shows excellent promise for clinical application.展开更多
Vibrations in aircraft hydraulic pipeline system,due to multi-source excitation of high fluid pressure fluctuation and serious vibration environment of airframe,can cause the pipeline system vibration failures through...Vibrations in aircraft hydraulic pipeline system,due to multi-source excitation of high fluid pressure fluctuation and serious vibration environment of airframe,can cause the pipeline system vibration failures through overload in engineering field.Controlling the vibrations in hydraulic pipeline is a challenging work to ensure the flight safety of aircraft.The common vibration control technologies have been demonstrated to be effective in typical structures such as aerospace structures,shipbuilding structures,marine offshore structures,motor structures,etc.However,there are few research literatures on vibration control strategies of aircraft hydraulic pipeline.Combining with the development trend of aircraft hydraulic pipeline system and the requirement of vibration control technologies,this paper provides a detailed review on the current vibration control technologies in hydraulic pipeline system.A review of the general approaches following the passive and active control technologies are presented,which are including optimal layout technique of pipeline and clamps,constrained layer damping technique,vibration absorber technique,hydraulic hose technique,optimal pump structure technique,and active vibration control technique of pipeline system.Finally,some suggestions for the application of vibration control technologies in engineering field are given.展开更多
基金This work is supported by Natural Science Foundation of Shandong Province(Grant no.ZR2018MEE021)Equipment Pre Research Fund Project(Grant no.61402100501).
文摘When designing a complex pipeline with long distance and multi-supports for offshore platform,it is necessary to analyze the vibration characteristics of the complex pipeline system to ensure that there is no harmful resonance in the working conditions.Therefore,the optimal layout of support is an effective method to reduce the vibration response of hydraulic pipeline system.In this paper,a developed dynamic optimization method for the complex pipeline is proposed to investigate the vibration characteristics of complex pipeline with multi-elastic supports.In this method,the Kriging response surface model between the support position and pipeline is established.The position of the clamp in the model is parameterized and the optimal solution of performance index is obtained by genetic algorithm.The number of clamps and the interval between clamps are considered as the constraints of layout optimization,and the optimization objective is the natural frequencies of pipeline.Taking a typical offshore pipeline as example to demonstrate the effectiveness of the proposed method,the results show that the vibration performance of the hydraulic pipeline system is distinctly improved by the optimization procedure,which can provide reasonable guidance for the design of complex hydraulic pipeline system.
基金financially supported by the Shanghai 2020 “Science and Technology Innovation Action Plan” Social Development Science and Technology Research Project(No.20dz1203600)the Fundamental Research Funds for the Central Universities,and the Open Funds for Characterization of Tongji University.
文摘Nicotinamide adenine dinucleotide (NAD+/NADH) pools homeostasis is recognized as an Achilles’ Heel in tumor metabolism reprogramming. However, mitochondria can enable cancer cells to overcome NADH exhaustion by providing NAD+ precursors and/or intermediates, thus promoting their survival rate and potentially driving uncontrollable proliferation. Here, a synergistic intervention NAD+/NADH homeostasis and mitochondrial metabolism strategy with magnetic resonance imaging (MRI)/photoacoustic imaging (PAI) are developed to address grand challenge of metabolic reprogramming for antitumor bioenergetic therapy. A mitochondrial-targeted cascade amplification nanoplatform ([β-MQ]TRL), triggered by NAD(P)H: quinone oxidoreductase-1 (NQO1), can enable a continuous depletion of cytosol NADH until cell death. The end-product, hydrogen peroxide (H_(2)O_(2)), can be further catalytically converted to higher toxic ·OH in proximity to mitochondria based on [β-MQ]TRL mediated Fenton-like reaction, hijacking tumorigenic energy sources and leading to mitochondrial dysfunction. Additionally, the mild thermal ablation enabled by [β-MQ]TRL further amplifies this cascade reaction to effectively prevent tumor metastasis and recurrence. This synchronous intervention strategy with MRI/PAI establishes unprecedented efficiency in antitumor bioenergetic therapy in vivo, which shows excellent promise for clinical application.
基金the National Natural Science Foundation of China(No.51805462)。
文摘Vibrations in aircraft hydraulic pipeline system,due to multi-source excitation of high fluid pressure fluctuation and serious vibration environment of airframe,can cause the pipeline system vibration failures through overload in engineering field.Controlling the vibrations in hydraulic pipeline is a challenging work to ensure the flight safety of aircraft.The common vibration control technologies have been demonstrated to be effective in typical structures such as aerospace structures,shipbuilding structures,marine offshore structures,motor structures,etc.However,there are few research literatures on vibration control strategies of aircraft hydraulic pipeline.Combining with the development trend of aircraft hydraulic pipeline system and the requirement of vibration control technologies,this paper provides a detailed review on the current vibration control technologies in hydraulic pipeline system.A review of the general approaches following the passive and active control technologies are presented,which are including optimal layout technique of pipeline and clamps,constrained layer damping technique,vibration absorber technique,hydraulic hose technique,optimal pump structure technique,and active vibration control technique of pipeline system.Finally,some suggestions for the application of vibration control technologies in engineering field are given.