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Model optimization method and connected-pipe experiment of a liquid fuel ramjet engine

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航空动力学报 2013年第6期28卷 1277-1285页

作者： ma qian-rong GUO Xin WU Hu CHOU qian School of Power and Energy Northwest Polytechnical University Aero-Engine Altitude Simulated Key Laboratory China Gas Turbine EstablishmentAviation Industry Corporation of China

The optimization method of a mathematical model and connected-pipe experimental technique for a test in altitude test facility (ATF) of a liquid fuel ramjet engine was *** optimization of the simple mathematical model was divided into two ***,using the test engine's geometry configuration size data,a preliminary adjustment was ***,using experimental test data,the components' experiential coefficients were modified *** was laid on the simulation technique of flight condition and parameters measurement *** experimental technique was applied to a ramjet ATF test *** comparison results show that the optimized-model has higher precision and the nozzle gross thrust difference drops from 12% to about 4%.

关键词： ramjet engine model optimization altitude test facility(ATF) connected-pipe experiment simulation technique

market-based solution in China to finance the clean from the dirty

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Fundamental Research 2024年第2期4卷 324-333页

作者： Haoqi qian rong ma Libo Wu Institute for Global Public Policy Fudan UniversityShanghai 200433China LSE-Fudan Research Centre for Global Public Policy Fudan UniversityShanghai 200433China School of Economics Fudan UniversityShanghai 200433China Shanghai Institute for Energy and Carbon Neutrality Strategy Fudan UniversityShanghai 200433China

Financial incentives play a key role in promoting renewable energy investments that can help China achieve the‘dual carbon’*** national emissions trading scheme(ETS)and the renewable energy portfolio standard(RPS)are two existing market-based policy instruments that can generate stable expected returns for low-carbon *** paper studies the interactive distribution effects of these two market-based *** use the micro-level thermal power plant data to investigate the abatement effects of the national ETS,in which the details show that the existing rate-based ETS will result in higher negative impacts on power units,whose installed capacities are smaller than 400 *** interactive distribution effects between the two markets will occur when the permit allocation standards of the national ETS become stricter than the existing *** in Eastern China and Northern China will face high pressure on costs in both ETS and RPS *** the levels of the permit allocation standards are set as 70%of the existing ones and the carbon price is assumed to be 200 yuan/ton in 2030,the annual market size of the national ETS will be nearly 100 billion yuan,and the annual market size is predicted to be 250 billion *** the existing rate-based national ETS,the China Certified Emission Reduction(CCER)mechanism will have an offsetting effect,which should be taken into serious consideration during the policy-making processes in the future.

关键词： Emission trading scheme Renewable energy portfolio standard Green finance Policy interactions China certified emission reduction Distribution effect

Spatial Distribution Pattern and Influencing Factors of Bed-and-breakfasts(B&Bs)from the Perspective of Urban-rural Differences:A Case Study of Jiaodong Peninsula,China

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Chinese Geographical Science 2024年第4期34卷 752-763页

作者： WANG Xinyue ma qian management College Ocean University of ChinaQingdao 266100China

There are significant differences between urban and rural bed-and-breakfasts(B&Bs)in terms of customer positioning,economic strength and spatial *** identifying the differences in spatial characteristics and influencing factors of each type,is essential for creating urban and rural B&B agglomeration *** study used density-based spatial clustering of applications with noise(DBSCAN)and the multi-scale geographically weighted regression(MGWR)model to explore similarities and differences in the spatial distribution patterns and influencing factors for urban and rural B&Bs on the Jiaodong Peninsula of China from 2010 to *** results showed that:1)both urban and rural B&Bs in Jiaodong Peninsula went through three stages:a slow start from 2010 to 2015,rapid development from 2015 to 2019,and hindered development from 2019 to ***,urban B&Bs demonstrated a higher development speed and agglomeration intensity,leading to an increasingly evident trend of uneven development between the two sectors.2)The clustering scale of both urban and rural B&Bs continued to expand in terms of quantity and *** B&B clusters characterized by a limited number,but a higher likelihood of transitioning from low-level to high-level *** the number of rural B&B clusters steadily increased over time,their clustering scale was comparatively lower than that of urban B&Bs,and they lacked the presence of high-level clustering.3)In terms of development direction,urban B&B clusters exhibited a relatively stable pattern and evolved into high-level clustering centers within the main urban ***,rural B&Bs exhibited a more pronounced spatial diffusion effect,with clusters showing a trend of multi-center development along the coastline.4)Transport emerged as a common influencing factor for both urban and rural B&Bs,with the density of road network having the strongest explanatory power for their spatial *** terms of differences,populati

关键词： urban-rural bed-and-breakfasts(B&Bs) spatiotemporal evolution density-based spatial clustering of applications with noise(DBSCAN)model multi-scale geographically weighted regression(MGWR) Jiaodong Peninsula China

Bioinspired nanomaterials for the treatment of bacterial infections

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Nano Research 2024年第2期17卷 691-714页

作者： Xiaojing ma Wenjing Tang rong Yang Robert F.Smith School of Chemical&Biomolecular Engineering Cornell UniversityIthacaNY 14853USA

Infectious diseases pose a serious threat to global *** immunizations can control most viral infections,bacterial infections,particularly those caused by drug-resistant strains,continue to cause high rates of illness and ***,the creation of new antibiotics has come to a grinding halt in the last ten *** response to this crisis,nanotechnology has emerged as a hopeful solution to tackle drug resistance and enhance treatment results.A large variety of biomimetic nanomaterials,termed nanozymes,have demonstrated strong antimicrobial *** the inherent toxicity of nanomaterials is a concern,recent studies have harnessed the stimuli-responsiveness of nanomaterials to enable local and/or targeted delivery to reduce the treatment side ***,the physicochemical versatility of nanomaterials affords many degrees of freedom that enable rational design of smart or autonomous therapeutics,which cannot be achieved using conventional *** design straddles the fields of catalysis,nanoscience,microbiology,and translational *** provide an overview of this interdisciplinary landscape,this review is organized based on composition into lipid,metal,metal oxide,and non-metallic *** as a delivery vehicle enhance bioavailability and reduce ***-and metal oxide-based nanomaterials inhibit bacterial growth by mimicking natural enzymatic activities such as peroxidase(POD)and ***,carbon-,polymer-,and cell membrane-based nanomaterials are combined into a discussion on non-metallic *** the end of this review,potentially fruitful directions for future bioinspired nanomaterials in infectious disease treatment are included.

关键词： bioinspired nanomaterial bacteria infectious disease antimicrobial liposome nanozyme

Further Results on Stability Analysis for Sampled-Data Systems via Refined Semi-Looped-Functional

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Journal of Systems Science & Complexity 2024年第1期37卷 318-328页

作者： SHENG Zhaoliang XU Shengyuan ma qian ZHANG Baoyong School of Automation Nanjing University of Science and TechnologyNanjing 210094China

This paper investigates the stability problem for sampled-data systems by adopting a refined semi-looped-functional,which is with the following two ***,the new functional term is with a new integral vectorη0,which contains sampling information of the systems and associates two commonly used ***,the vectorη0 is combined into various zero equations for processing the functional,especially where a new equation is derived fromη*** on the refined functional,further stability results for sampled-data systems are *** the effectiveness of the results is numerically verified through two examples at the end.

关键词： Integral vector sampled-data systems semi-looped-functional stability analysis.

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堵塞条件下发动机高空试验推力差异分析

推进技术 2021年第3期42卷 481-487页

作者：马前容周杰仇钎李康中国航发四川燃气涡轮研究院高空模拟技术重点实验室四川绵阳621000

堵塞技术是降低发动机高空模拟试验成本和解决设备抽气能力不足的可行手段。在不同喷管排气环境压力条件下,某型带拉瓦尔喷管涡扇发动机完成了四组堵塞对推力影响的试验,发动机总推力试验值最大差异为6.2%。为揭示试验推力差异产生的原... 详细信息

堵塞技术是降低发动机高空模拟试验成本和解决设备抽气能力不足的可行手段。在不同喷管排气环境压力条件下,某型带拉瓦尔喷管涡扇发动机完成了四组堵塞对推力影响的试验,发动机总推力试验值最大差异为6.2%。为揭示试验推力差异产生的原因,提高堵塞条件下发动机高空试验推力评估的准确性,开展了相关的理论分析和一维仿真计算,提出了主要影响量估算方法。结果表明:推力差异主要与发动机转速、结果修正方法和喷管扩张段流场特性有关;按文中提出的主要影响量估算方法计算了这些因素对推力的影响量,扣除影响量后总推力的最大差异降至0.8%;相同转速下,总推力相似换算值随喷管排气压力的升高呈增大趋势,最大差异达到3.3%。

关键词：堵塞技术推力发动机高空试验拉瓦尔喷管

Guaranteed Cost Attitude Tracking Control for Uncertain Quadrotor Unmanned Aerial Vehicle Under Safety Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1447-1457页

作者： qian ma Peng Jin Frank L.Lewis School of Automation Nanjing University of Science and TechnologyNanjing 210094China UTA Research Institute University of Texas at ArlingtonFort WorthTexas 76118 USA IEEE

In this paper,guaranteed cost attitude tracking con-trol for uncertain quadrotor unmanned aerial vehicle(QUAV)under safety constraints is ***,an augmented system is constructed by the tracking error system and reference *** transformation aims to convert the tracking control prob-lem into a stabilization control ***,control barrier function and disturbance attenuation function are designed to characterize the violations of safety constraints and tolerance of uncertain disturbances,and they are incorporated into the reward function as penalty *** on the modified reward function,the problem is simplified as the optimal regulation problem of the nominal augmented system,and a new Hamilton-Jacobi-Bellman equation is ***,critic-only rein-forcement learning algorithm with a concurrent learning tech-nique is employed to solve the Hamilton-Jacobi-Bellman equa-tion and obtain the optimal *** proposed algorithm can not only ensure the reward function within an upper bound in the presence of uncertain disturbances,but also enforce safety *** performance of the algorithm is evaluated by the numerical simulation.

关键词： Attitude tracking control quadrotor unmanned aerial vehicle(QUAV) reinforcement learning safety constraints uncertain disturbances.

Preparation of K-doped g-C_(3)N_(4) composite loaded on magnetic attapulgite and its degradation performance for malachite green

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Chinese Journal of Chemical Engineering 2024年第7期71卷 110-121页

作者： Aishun ma Hanlin qian Hongxia Liu Sili Ren Jiangxi Key Laboratory of Mining&Metallurgy Environmental Pollution Control Jiangxi University of Science and TechnologyGanzhou 341000China Jiangxi Provincial Key Laboratory of Low-Carbon Processing and Utilization of Strategic Metal Mineral Resources Jiangxi University of Science and TechnologyGanzhou 341000China

Visible-light-driven photocatalysis is a promising technology for the treatment of dye *** this work,a novel photocatalyst of K-doped g-C_(3)N_(4) loaded on magnetic attapulgite(ATP)(Kω-g-C_(3)N_(4)@ATP-Fe_(3)O_(4))with excellent visible light photocatalytic properties and stability were successfully prepared and *** removal efficiency of Kω-g-C_(3)N_(4)@ATP-Fe_(3)O_(4) for malachite green(MG)was studied,and the degradation mechanism was analyzed and *** was found that the K_(5)-g-C_(3)N_(4)@ATP-Fe_(3)O_(4) photocatalyst possessed excellent degradation efficiency of over 98.0%for the MG dye wastewater under optimal ***,the K_(5)-g-C_(3)N_(4)@ATP-Fe_(3)O_(4) materials possessed good recyclability with a removal rate over 82%after 4 *** visible light condition,the K_(5)-g-C_(3)N_(4)@ATP-Fe_(3)O_(4) photocatalyst produce radicals of·OH and O_(2)^(-)to degrade the MG dyes,which was supported by electron paramagnetic resonance(EPR)and radical trapping *** addition,the LC-MS analysis interpreted the degradation pathways and intermediates of MG in the *** findings in this work indicate that the prepared photocatalytic material has excellent degradation efficiency for MG and can be applied in dye wastewater treatment.

关键词： Photocatalyst malachite green K-doped g-C_(3)N_(4) Degradation

Milk fat globule epidermal growth factor 8 alleviates liver injury in severe acute pancreatitis by restoring autophagy flux and inhibiting ferroptosis in hepatocytes

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World Journal of Gastroenterology 2024年第7期30卷 728-741页

作者： Qing Cui Hang-Cheng Liu Wu-Ming Liu Feng ma Yi Lv Jian-Cang ma rong-qian Wu Yi-Fan Ren Department of Cardiology Xi’an Central Hospital Affiliated to Xi’an Jiaotong UniversityXi’an 710003Shaanxi ProvinceChina Department of General Surgery The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710004Shaanxi ProvinceChina National Local Joint Engineering Research Center for Precision Surgery&Regenerative Medicine Shaanxi Provincial Center for Regenerative Medicine and Surgical EngineeringFirst Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina Department of Vascular Surgery The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710004Shaanxi ProvinceChina

BACKGROUND Liver injury is common in severe acute pancreatitis(SAP).Excessive autophagy often leads to an imbalance of homeostasis in hepatocytes,which induces lipid peroxidation and mitochondrial iron deposition and ultimately leads to *** previous study found that milk fat globule epidermal growth factor 8(MFG-E8)alleviates acinar cell damage during SAP via binding toαvβ3/5 ***-E8 also seems to mitigate pancreatic fibrosis via inhibiting chaperone-mediated *** To speculate whether MFG-E8 could also alleviate SAP induced liver injury by restoring the abnormal autophagy *** SAP was induced in mice by 2 hly intraperitoneal injections of 4.0 g/kg L-arginine or 7 hly injections of 50μg/kg cerulein plus ***8-knockout mice were used to study the effect of MFG-E8 deficiency on SAPinduced liver ***,a specificαvβ3/5 integrin inhibitor,was used to investigate the possible mechanism of *** The results showed that MFG-E8 deficiency aggravated SAP-induced liver injury in mice,enhanced autophagy flux in hepatocyte,and worsened the degree of *** MFG-E8 reduced SAP-induced liver injury in a dose-dependent ***,MFG-E8 mitigated excessive autophagy and inhibited ferroptosis in liver *** abolished MFG-E8’s beneficial effects in SAP-induced liver *** MFG-E8 acts as an endogenous protective mediator in SAP-induced liver ***-E8 alleviates the excessive autophagy and inhibits ferroptosis in hepatocytes by binding to integrinαVβ3/5.

关键词： Autophagy flux Ferroptosis Liver injury Milk fat globule epidermal growth factor 8 αvβ3/5 integrins Acute pancreatitis