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Multi-Factor Intensity Estimation for Tropical Cyclones in the Western North Pacific Based on the Deviation Angle Variance Technique

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Journal of Meteorological Research 2020年第5期34卷 1038-1051页

作者： Wei ZHONG meng yuan Hexin YE Xia LUO College of Meteorology and Oceanology National University of Defense TechnologyNanjing 211101 Submarine College of Navy Qingdao 266199

In this paper, the infrared cloud images from Fengyun series geostationary satellites and the best track data from the China Meteorological Administration(CMA-BST) in 2015–2017 are used to investigate the effects of two multifactor models, generalized linear model(GLM) and long short-term memory(LSTM) model, for tropical cyclone(TC) intensity estimation based on the deviation angle variance(DAV) technique. For comparison, the typical singlefactor Sigmoid function model(SFM) with the map minimum value of DAV is also used to produce TC intensity estimation. Sensitivity experiments regarding the DAV calculation radius and different training data groups are conducted, and the estimation precision and optimum calculation radius for DAV in the western North Pacific(WNP) are analyzed. The results show that the root-mean-square-error(RMSE) of the single-factor SFM is 8.79–13.91 m s^-1 by using the individual years as test sets and the remaining two years as training sets with the optimum calculation radius of 550 km. However, after selecting and using the high-correlation multiple factors from the same test and training data, the RMSEs of GLM and LSTM models decrease to 5.93–8.68 and 4.99–7.00 m s^-1 respectively, with their own optimum calculation radii of 350 and 400 km. All the sensitivity experiments indicate that the SFM results are significantly influenced by the DAV calculation radius and characteristics of the training set data, while the results of multi-factor models appear more stable. Furthermore, the multi-factor models reduce the optimum radius within the process of DAV calculation and improve the precision of TC intensity estimation in the WNP, which can be chosen as an effective approach for TC intensity estimation in marine areas.

关键词： deviation angle variance(DAV)technique tropical cyclone(TC) intensity estimation

Achieving high ductility and low in-plane anisotropy in magnesium alloy through a novel texture design strategy

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Journal of Magnesium and Alloys 2024年第7期12卷 2863-2873页

作者： Shi Liu Cheng Wang Hong Ning Zhao-yuan meng Kai Guan Hui-yuan Wang State Key Laboratory of Automotive Simulation and Control Jilin UniversityPR China Key Laboratory of Automobile Materials of Ministry of Education&School of Materials Science and Engineering Nanling CampusJilin UniversityNo.5988 Renmin StreetChangchun130025 PR China State Key Laboratory of Reliability and Intelligence of Electrical Equipment School of Material Science and EngineeringHebei University of TechnologyTianjin300130 PR China

Texture regulation is a prominent method to modify the mechanical properties and anisotropy of magnesium *** this work,the Mg-1Al-0.3Ca-0.5Mn-0.2Gd(wt.%)alloy sheet with TD-tilted and circular texture was fabricated by unidirectional rolling(UR)and multidirectional rolling(MR)method,*** generating a strong in-plane mechanical anisotropy in conventional TD-tilted texture,the novel circular texture sample possessed a weak in-plane yield *** can be rationalized by the similar proportion of soft grains with favorable orientation for basalslip and{10.12}tensile twinning during the uniaxial tension of circular-texture sample along different ***,compared with the TD-tilted texture,the circular texture improved the elongation to failure both along the rolling direction(RD)and transverse direction(TD).By quasi-in-situ EBSD-assisted slip trace analysis,higher activation of basal slip was observed in the circular-texture sample during RD tension,contributing to its excellent *** loading along the TD,the TD-tilted texture promoted the activation of{10.12}tensile twins significantly,thus providing nucleation sites for cracks and deteriorating the *** research may shed new insights into the development of formable and ductile Mg alloy sheets by texture modification.

关键词： Magnesium alloy TD-tilted texture Circular texture In-plane yield anisotropy Ductility

Influence of H_(2)S and NH_(3) on biogas dry reforming using Ni catalyst:a study on single and synergetic effect

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Frontiers of Environmental Science & Engineering 2023年第3期17卷 63-74页

作者： Yuchen Gao Jianguo Jiang yuan meng Tongyao Ju Siyu Han School of Environmental Science and Engineering Tiangong UniversityTianjin 300387China School of Environment Tsinghua UniversityBeijing 100084China

Biogas is a renewable biomass energy source mainly composed of CH4 and CO_(2).Dry reforming is a promising technology for the high-value utilization of *** impurity gases in biogas can not be completely removed after pretreatment,which may affect the performance of dry *** this study,the influence of typical impurities H_(2)S and NH_(3) on dry reforming was studied using Ni/MgO *** results showed that low concentration of H_(2)S in biogas could cause serious deactivation of *** results including EDS,XPS and TOF-SIMS confirmed the adsorption of sulfur on the catalyst surface,which was the cause of catalyst *** used air calcination method to regenerate the sulfur-poisoned catalysts and found that the regeneration temperature higher than 500℃could help catalyst recover the original ***_(3)in the concentration range of 50–10000 ppm showed a slight inhibitory effect on biogas dry *** decline rate of biogas conversion efficiency increased with the increase of NH_(3) *** was related to the reduction of oxygen activity on catalyst surface caused by NH_(3).The synergetic effect of H_(2)S and NH_(3)in biogas was *** results showed that biogas conversion decreased faster under the coexistence of H_(2)S and NH_(3)than under the effect of H_(2)S alone,so as the surface oxygen activity of *** calcination regeneration could also recover the activity of the deactivated catalyst under the synergetic effect of H_(2)S and NH_(3).

关键词： Biogas Dryreforming Suifur poisoning Ammonia Synergetic effect Hydrogen

Effect of tadalafil in chronic renal failure rabbits:relevance to erectile dysfunction

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第6期12卷 455-459页

作者： meng-yuan ZHANG Qiang FU Wei BIAN Department of Urology Provincial Hospital Affiliated to Shandong University Jinan 250021 China

It is of great importance to investigate an effective and reliable medication against chronic renal failure (CRF)-related erectile dysfunction (ED),which aims to improve patients' life *** concentrations of cyclic guanosine monophosphate (cGMP) in the corpus cavernosal smooth muscle of both CRF and control rabbits were *** effects of various concentrations of tadalafil,papaverine,and sodium nitroprusside on the relaxation responses of corpus cavernosal smooth muscle pre-contracted with phenylephrine in CRF rabbits were *** was significant difference in the concentration of cGMP between CRF and control rabbits (P<0.01).Tadalafil had the greatest impacts on CRF rabbits when given the same concentration of papaverine or sodium nitroprusside and particularly significant differences were identified under the concentration levels of 10-5 and 10-4 mol/L (P<0.01).The results suggest that the cGMP concentrations of the corpus cavernosum had been greatly reduced in CRF rabbits compared with control rabbits and that tadalafil may be an ideal medication for use in the treatment of CRF-related ED.

关键词： Chronic renal failure Erectile dysfunction Phosphodiesterase inhibitor Tadalafil

Fate and risk assessment of emerging contaminants in reclaimed water production processes

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Frontiers of Environmental Science & Engineering 2021年第5期15卷 295-310页

作者： yuan meng Weiyi Liu Heidelore Fiedler Jinlan Zhang Xinrui Wei Xiaohui Liu meng Peng Tingting Zhang Department of Environmental Science and Engineering Research Centre for Resource and EnvironmentBeijing University of Chemical TechnologyBeijing100029China MTM Research Centre School of Science and TechnologyOrebro UniversityOrebroSE-70182Sweden State Key Laboratory of Environmental Criteria and Risk Assessment National Engineering Laboratory for Lake Pollution Control and Ecological RestorationResearch Centre of Lake EnvironmentChinese Research Academy of Environmental SciencesBeijing100012China School of Environment Tsinghua UniversityBeijing100084China

Reclaimed water has been widely applied in irrigation and industrial *** the behavior of emerging contaminants in the production process of reclaimed water is the first prerequisite for developing relevant water quality *** study investigated 43 emerging contaminants,including 22 pharmaceuticals and personal care products(PPCPs),11 organophosphorus flame retardants(OPFRs),and 10 antibiotic resistance genes(ARGs)in 3 reclaimed wastewater treatment plants(RWTPs)in *** composition profiles and removal efficiencies of these contaminants in RWTPs were *** results indicated that the distribution characteristics of the different types of contaminants in the three RWTPs were ***,sul2 and tris(1-chloro-2-propyl)phosphate were the dominant substances in the wastewater,and their highest concentrations were 27104 ng/L,1.4×10^(7) copies/mL and 262 ng/L,*** and sul2 were observed to be the dominant substances in the sludge,and their highest concentrations were 5419 ng/g and 3.7×10^(8) copies/g,***/anoxic/oxic system combined with the membrane bioreactor process achieved a relatively high aqueous removal of PPCPs(87%).ARGs and OPFRs were challenging to remove,with average removal rates of 6.5%and 31%,*** meta-analysis indicated that tertiary treatment processes performed better in emerging contaminant removal than secondary *** exhibited the highest mass load discharge,with 33.5 mg/d per 1000 *** and tris(2-ethylhexyl)phosphate posed high risks(risk quotient>1.0)to aquatic *** study provides essential evidence to screen high priority pollutants and develop corresponding standard in RWTPs.

关键词： Trace organic pollution Antibiotic resistance genes Reclaimed wastewater Sludge Risk assessment Mass load

Temperature and pH Dually-responsive Poly(β-amino ester) Nanoparticles for Drug Delivery

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Chinese Journal of Polymer Science 2017年第4期35卷 534-546页

作者：卢小菊 xiang-yu yang yuan meng shao-zhen li School of Chemical and Material Engineering and Institute of Quantum Materials Hubei Polytechnic University Huangshi 435003 China

Stimuli-responsive polymers have undoubtedly been of great interest in the past decades due to a variety of their potential applications in biomedical territory. However, their non-degradability limits their in vivo applications. Herein, we report a novel pH and temperature dual-stimuli responsive-poly（β-amino ester）. The pH/temperature sensitivities are interrelated and can be easily tuned by changing PEG-diacrylate chain length and the percentage of biamines in the feed ratio. These dual-responsive polymers are very useful in drug delivery. Reaction of methyl ether poly（ethylene glycol）（MPEG） and poly（β-amino ester） resulted in an amphiphilic MPEG-PBAE block copolymer which could form nanoparticles by self- assembly. A hydrophobic drug （DOX） was loaded in the self-assembled nanoparticles at low temperature without using organic solvents. The loaded drug was released very slowly and steadily at 37 ℃ under physiological conditions （pH 7.4）, but rapidly released from the micelles in weakly acidic environments （pH 6.4 and 5.0） for intracellular drug release. Thus, these poly（fl-amino ester） polymers constitute ideal drug carriers since their thermal sensitivity allows the drug loadings without using organic solvent and their pH sensitivity permits fast intracellular drug release.

关键词： Temperature-sensitive pH-sensitive Nanoparticles Drug delivery

Comprehensive profiling and evaluation of the alteration of RNA modifications in thyroid carcinoma by liquid chromatography-tandem mass spectrometry

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Chinese Chemical Letters 2022年第8期33卷 3772-3776页

作者： meng-yuan Chen Chu-Bo Qi Xiao-meng Tang Jiang-Hui Ding Bi-Feng yuan Yu-Qi Feng School of Public Health Wuhan UniversityWuhan 430071China Department of Chemistry Sauvage Center for Molecular SciencesWuhan UniversityWuhan 430072China Jiangxi Provincial People's Hospital Affiliated to Nanchang University Nanchang 330006China

RNA molecules contain diverse modifications that display important functions in a variety of physiological and pathological *** far over 150 chemical modifications have been characterized to be present in various RNA species,such as in messenger RNA(mRNA),ribosomal RNA(rRNA),and transfer RNA(tRNA).Previous studies revealed that certain RNA modifications were correlated to specific human diseases,indicating RNA modifications could serve as the potential indicator of human ***,systemic investigation of the alteration of RNA modifications in different RNA species of carcinoma tissues are still ***,we carried out the comprehensive profiling and evaluation of the alteration of RNA modifications in thyroid carcinoma by liquid chromatography-tandem mass spectrometry(LC-ESIMS/MS)*** developed method allowed us to simultaneously detect 48 different types of RNA *** this method,we detected 10,15,14,and 25 modifications in m RNA,18 S r RNA,28 S rRNA and small RNA(<200 nt),*** to the normal tissues,we revealed a total of 14 RNA modification exhibited significant increase and 2 RNA modifications showed significant decrease in thyroid carcinoma *** study provided the first comprehensive profile as well as the alteration of modifications in different RNA species in thyroid carcinoma and matched tumor-adjacent normal *** altered pattern RNA modifications may serve as the indicator of thyroid ***,this study may promote the in-depth understanding of the regulatory roles of RNA modifications in thyroid carcinoma.

关键词： RNA modification Liquid chromatography-mass spectrometry Thyroid carcinoma Profiling

Stability and Nonlinear Response Analysis of Parametric Vibration for Elastically Constrained Pipes Conveying Pulsating Fluid

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Acta Mechanica Solida Sinica 2023年第2期36卷 230-240页

作者： meng-yuan Hao Hu Ding Xiao-Ye Mao Li-Qun Chen Shanghai Key Laboratory of Mechanics in Energy Engineering School of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China

Usually,the stability analysis of pipes with pulsating flow velocities is for rigidly constrained pipes or cantilevered *** this paper,the effects of elastic constraints on pipe stability and nonlinear responses under pulsating velocities are investigated.A mechanical model of a fluid-conveying pipe under the constraints of elastic clamps is established.A partial differentialintegral nonlinear equation governing the lateral vibration of the pipe is *** natural frequencies and mode functions of the pipe are ***,the stable boundary and nonlinear steady-state responses of the parametric vibration for the pipe are established ***,the analytical solutions are verified *** results of this work reveal some interesting *** is found that the elastic constraint stiffness in the direction perpendicular to the axis of the pipe does not affect the critical flow velocity of the ***,the constraint stiffness has a significant effect on the instability boundary of the pipe with pulsating flow ***,an increase in the stiffness of the constraint increases the instable region of the pipe under parametric ***,when the constraint stiffness is increased,the steady-state response amplitude of the nonlinear vibration for the pipe is significantly ***,the effects of the constraint stiffness on the instable region and vibration responses of the fluid-conveying pipe are different when the flow velocity is pulsating.

关键词： Pipe conveying fluid Elastic boundary Stability Nonlinear dynamics Parametric vibration Multi-scale method

Posture control of a 3-RPS pneumatic parallel platform with parameter initialization and an adaptive robust method

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Frontiers of Information Technology & Electronic Engineering 2017年第3期18卷 303-316页

作者： Guo-liang TAO Ce SHANG De-yuan meng Chao-chao ZHOU The State Key Laboratory of Fluid Power Transmission and Control Zhejiang University School of Mechatronic Engineering China University of Mining and Technology

A control algorithm for a 3-RPS parallel platform driven by pneumatic cylinders is discussed. All cylinders are controlled by proportional directional valves while the kinematic and dynamic properties of the system are modeled. The method of adaptive robust control is applied to the controller using a back-stepping approach and online parameter estimation. To compensate for the uncertainty and the influence caused by estimations, a fast dynamic compensator is integrated in the controller design. To prevent any influence caused by the load applied to the moving platform changing in a practical working situation, the identification of parameters is taken as the initialization of unknown parameters in the controller, which can improve the adaptability of the algorithm. Using these methods, the response rate of the parameter estimation and control performance were improved *** adverse effects of load and restriction forces were eliminated by the initialization and online *** under different situations illustrated the effectiveness of the adaptive robust controller with parameter initialization, approaching average tracking errors of less than 1%.

关键词： Parameter initialization Adaptive robust control Parallel mechanism Pneumatic cylinders