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高良姜多糖的提取及其活性研究

惠州学院学报 2024年第3期44卷 43-48,63页

作者：黎鹏辉陈婷婷黄雪娴刘家欣邝颖欣陈晓嫚童丹惠州学院生命科学学院广东惠州516007

采用水提醇沉和单因素实验获得较优的高良姜多糖提取方法。以对DPPH·自由基、超氧阴离子自由基的清除率为指标,评价高良姜多糖的抗氧化能力,同时研究其对酪氨酸酶抑制以及抗菌活性,探讨其在护肤品领域的潜在应用。获得高良姜多糖较优... 详细信息

采用水提醇沉和单因素实验获得较优的高良姜多糖提取方法。以对DPPH·自由基、超氧阴离子自由基的清除率为指标,评价高良姜多糖的抗氧化能力,同时研究其对酪氨酸酶抑制以及抗菌活性,探讨其在护肤品领域的潜在应用。获得高良姜多糖较优的提取方法为:提取温度为70℃、提取时间为40 min、料液比为1∶40(g/mL),此时多糖得率为11.62%,含量为20.0%。同时,研究发现高良姜多糖对DPPH·自由基和超氧阴离子自由基具有较强的清除率,均表现出质量浓度依赖性;研究发现高良姜多糖对酪氨酸酶具有较强的抑制活性,IC50值为2.69 mg/mL;此外,研究发现高良姜多糖对白色念珠菌和金黄色葡萄球菌具有较强的抑制作用。结果表明,高良姜多糖在护肤品方面具有较好的应用前景。

关键词：高良姜多糖抗氧化活性酪氨酸酶抗菌

Low-cost hybrid integrated 4 × 25 GBaud PAM-4CWDM ROSA with a PLC-based arrayed waveguide grating de-multiplexer

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Photonics Research 2019年第7期7卷 37-42页

作者： Lei Liu Limin Chang yingxin kuang Zezheng Li Yang Liu Huan Guan Manqing Tan Yude Yu Zhiyong Li State Key Laboratory of Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 101408China

We demonstrate a low-cost hybrid integrated and compact 100 GBaud four-lane coarse wavelength division multiplexing (CWDM) receiver optical sub-assembly (ROSA) based on an arrayed waveguide grating de-multiplexer in the O band. To achieve the horizontal light coupling between the planar light-wave circuit (PLC) based arrayed waveguide grating de-multiplexer and photodetector array, a 42°polished facet is applied for total reflection.A flexible printed circuit with high-frequency coplanar waveguides is used for a power supply of trans-impedance amplifier and signal *** fabricated CWDM ROSA module, whose size is 18mm×22mm×6mm, shows a 3 dB bandwidth of 21.2,18.4,19.6,and 19.3 GHz,respectively,in each lane. The overall symbol error rates are at a magnitude of 10^-7 for 25 GBaud four-level pulse amplitude modulation (PAM-4) transmission with an average input optical power of 5dBm.

关键词： CWDM ROSA division optical compact facet pulse dB

Airflow Analytical Toolkit(AAT):A MATLAB-based analyzer for holistic studies on the dynamic characteristics of airflows

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Building Simulation 2024年第7期17卷 1137-1159页

作者： Zuoyu Xie Junhui Fan Bin Cao yingxin Zhu Department of Building Science School of ArchitectureTsinghua UniversityBeijingChina Key Laboratory of Eco Planning&Green Building Ministry of Education(Tsinghua University)BeijingChina

The dynamic characteristics of different airflows on micro-scales have been explored from many perspectives since the late *** the one hand,most analytical tools and research subjects in previous contributions vary significantly:some only focus on fluctuant velocity features,while others pay attention to directional *** the other hand,despite the wide variety of existing analytical methods,they are not systematically classified and *** paper aims to establish a system including state-of-the-art tools for airflow analysis and to further design a holistic toolkit named Airflow Analytical Toolkit(AAT).The AAT contains two tools,responsible for analyzing the velocity and direction characteristics of airflows,each of which is integrated with multiple analytical *** assess the performance of the developed toolkit,we further take typical natural and mechanical winds as cases to show its excellent analytical *** the help of this toolkit,the great differences in velocity and directional characteristics among different airflows are *** comparative results reveal that not only is the velocity of natural wind more fluctuating than that of mechanical wind,but its incoming flow direction is also more *** AAT,serving as a powerful and user-friendly instrument,will hopefully offer great convenience in data analysis and guidance for a deeper understanding of the dynamic characteristics of airflows,and further remedy the gap in airflow analytical tools.

关键词： airflow analysis dynamic characteristic wind velocity wind direction thermal comfort wind comfort

An air combat maneuver pattern extraction based on time series segmentation and clustering analysis

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Defence Technology（防务技术） 2024年第6期36卷 149-162页

作者： Zhifei Xi yingxin Kou Zhanwu Li Yue Lv You Li Air Force Engineering University No.1 Baling RoadBaqiao DistrictXi'anShaanxi ProvinceChina

Target maneuver recognition is a prerequisite for air combat situation awareness,trajectory prediction,threat assessment and maneuver *** get rid of the dependence of the current target maneuver recognition method on empirical criteria and sample data,and automatically and adaptively complete the task of extracting the target maneuver pattern,in this paper,an air combat maneuver pattern extraction based on time series segmentation and clustering analysis is proposed by combining autoencoder,G-G clustering algorithm and the selective ensemble clustering analysis ***,the autoencoder is used to extract key features of maneuvering trajectory to remove the impacts of redundant variables and reduce the data dimension;Then,taking the time information into account,the segmentation of Maneuver characteristic time series is realized with the improved FSTS-AEGG algorithm,and a large number of maneuver primitives are extracted;Finally,the maneuver primitives are grouped into some categories by using the selective ensemble multiple time series clustering algorithm,which can prove that each class represents a maneuver *** maneuver pattern extraction method is applied to small scale air combat trajectory and can recognize and correctly partition at least 71.3%of maneuver actions,indicating that the method is effective and satisfies the requirements for engineering *** addition,this method can provide data support for various target maneuvering recognition methods proposed in the literature,greatly reduce the workload and improve the recognition accuracy.

关键词： Maneuver pattern extraction Data mining Fuzzy segmentation Selective ensemble clustering

Optimizing evasive maneuvering of planes using a flight quality driven model

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Science China(Information Sciences) 2024年第3期67卷 197-208页

作者： Chang LIU Shaoshan SUN Chenggang TAO yingxin SHOU Bin XU School of Automation Northwestern Polytechnical University Chengdu Aircraft Design & Research Institute of AVIC

This paper investigates the optimal evasive maneuver for a plane to avoid an incoming missile. To accurately model the system dynamics while improving computational efficiency, a simplified plane model based on flight quality is established. A missile model with proportional guidance is also *** problem of determining the optimal evasion plane maneuver is formulated. The Gauss pseudospectral method(GPM) is proposed as a solution to find the optimal maneuver. The optimized maneuver is validated by testing it on a high-fidelity 6-degree-of-freedom(6-DOF) model, which demonstrates the effectiveness of the proposed simplified plane model. The Monte Carlo method is employed to evaluate the capability of the plane to evade missiles in various scenarios and elucidate general principles for successful evasion.

关键词： optimal maneuver flying quality evasive strategy pursuit-evasion game air-to-air combat

Liquid metal droplet dynamics

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Droplet 2024年第1期3卷 61-94页

作者： Xi Zhao Mengwen Qiao yingxin Zhou Jing Liu Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijingChina School of Future Technology University of Chinese Academy of SciencesBeijingChina Department of Biomedical Engineering School of MedicineTsinghua UniversityBeijingChina

The unique properties to combine the dual merits of both liquids and metals together make the gallium‐based liquid metal(LM)droplets a class of unconventional substitute which possess great potential for a group of newly emerging areas,such as stretchable electronics,soft devices,micro sensors and *** addition,LM droplets are undoubtedly an intriguing target worth of pursuing in fundamental hydrodynamic investigations due to their extremely high surface tension nature compared to classical nonmetallic *** the discovery of the diverse transformation phenomena and self‐fueled droplet mollusks of LM that can move automatically in solution via single electricity or even without any external energy supply,tremendous attentions were attracted to this special fluidic object of LM *** the past decade,there has been a proliferation of explorations on LM droplet dynamics,while the involved contents are heterogeneous due to the interfacial physical/chemical activity of the LM and the diversity of the kinetic *** better understand and manipulate the droplet behavior and to promote further development of the LMs,this review is dedicated to summarize the latest progress and presents an overview on basic findings related to LM macrodroplet ***,the extended definition of LM droplets and the corresponding fabrication methods are ***,typical works on LM droplet dynamics are systematically interpreted based on their different behavior ***,the perspectives,main obstacles and challenges restricting the development of LM droplet dynamics are pointed out.

关键词： dynamics behavior doubt

Modelling and mechanical characteristics of PDC cutter-rock interaction by combining mixed fragmentation modes with dynamic rock strength

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Petroleum 2024年第3期10卷 474-482页

作者： Guangjian Dong Ping Chen Xudong Wang Jianhong Fu yingxin Yang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500China School of Petroleum Engineering Southwest Petroleum UniversityChengdu610500China Periodical Office of Southwest Petroleum University Southwest Petroleum UniversityChengdu610500China School of Mechatronic Engineering Southwest Petroleum UniversityChengdu610500China

Polycrystalline diamond compact(PDC)bit is one of the most widely used drill bits for improving the rate of penetration in deep oil and gas well and geothermal ***,the dynamic rock fragmentation mechanics characteristics of PDC bits are still unclearly.A coupled fragmentation mechanics model of PDC cutter-rock interaction is established by combining the mixed fragmentation modes with dynamic *** coupling influence laws of cutter angle,cutting depth,dynamic strength ratio,breaking modes on the horizontal force coefficient(HFC),vertical force coefficient(VFC)and specific energy are *** model of this paper can optimize cutter inclination angle,cutting depth and minimum specific *** the increase of the cutter inclination angle,the dynamic VFC changes into two *** definition of the dynamic modes depends on the dynamic strength *** the cutting angle increases,the cutting force *** cutting force increases nonlinearly with increasing cutting *** specific energy of rock fragmentation increases nonlinearly with increasing cutting *** the increase of dynamic strength,the specific energy of rock fragmentation increases *** the input-energy increases,the rate of penetration response is divided into three *** results have important guiding significance for the PDC bit design and drilling parameters optimization to increase the rate of penetration and the efficiency of exploration and development.

关键词： Mechanical characteristics PDC cutter-rock inter action Mixed fragmentation modes Dynamic rock strength

Incubation temperature induced developmental plasticity of cold responsive physiological phenotypes in Japanese Quails

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Avian Research 2024年第3期15卷 385-394页

作者： yingxin Kou Rongmiao Zhang Xiaoqian Li Na Zhu Yihang Huang Shuping Zhang College of Life and Environmental Sciences Minzu University of ChinaBeijing100081China

Embryonic development is a critical period for phenotype *** variation during embryonic development can induce changes in postnatal phenotypes of *** thyroxine secretion and aerobic metabolic activity of small birds are important phenotypes closely related to their winter *** the context of climate change,it is necessary to determine whether temperature variation during incubation in birds leads to developmental plasticity of these cold responsive *** incubated Japanese Quail(Coturnix japonica)eggs at 36.8℃,37.8℃,and 38.8℃,and raised the chicks to 35-day old at 22℃with same raising conditions,then all the quails were exposed to gradually temperature dropping environment(from 15℃to 0℃).After cold treatment,serum T3 level,resting metabolic rate,skeletal muscle and liver metabolomes of the birds were *** serum T3 levels were significantly lower in the 38.8℃group and significantly higher in the 36.8℃group compared to the 37.8℃*** metabolic rate in the 38.8℃group was significantly lower compared to the 37.8℃*** with the 37.8℃group,metabolites involved in the tricarboxylic acid cycle in the liver were significantly lower in the 38.8℃group,and metabolites related to lipid oxidation metabolism and fatty acid biosynthesis were significantly lower in the skeletal muscles in the 38.8℃group but significantly higher in the 36.8℃*** results indicate that incubation temperature variation can lead to developmental plasticity in cold responsive physiological *** incubation temperature may impair the capacity of birds coping with cold challenge.

关键词： Cold response Developmental plasticity Incubation temperature Metabolic rate Metabolomes Precocial bird Thyroxin

Wearable pressure sensors based on antibacterial and porous chitosan hydrogels for full-range human motion detection

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Science China(Technological Sciences) 2024年第8期67卷 2475-2484页

作者： ZHANG yingxin LIU HanGuang JIN ShunYu LI YaJuan ZHANG Wan ZHOU Hang NIE ZanXiang HUANG Yuan School of Microelectronics Science and Technology Sun Yat-sen UniversityGuangzhou 510275China Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230022China Department of Clinical Laboratory the First Affiliated Hospital of Anhui Medical UniversityHefei 230022China School of Electronic and Computer Engineering Peking University Shenzhen Graduate SchoolShenzhen 518055China Zinergy Shenzhen Ltd. Shenzhen 518109China

Wearable pressure sensors made from conductive hydrogels hold significant potential in health ***,limited pressure range(Pa to hundreds of kPa)and inadequate antibacterial properties restrict their practical applications in diagnostic and health ***,a wearable high-performance pressure sensor was assembled using a facilely prepared porous chitosan-based hydrogel,which was constructed from commercial phenolphthalein particles as a sacrificial *** relationship between the porosity of hydrogels and sensing performance of sensors was systematically ***,the wearable pressure sensor,featuring an optimized porosity of hydrogels,exhibits an ultrawide sensing capacity from 4.83 Pa to 250 k Pa(range-to-limit ratio of 51,760)and high sensitivity throughout high pressure ranges(0.7 kPa~(-1),120–250 kPa).The presence of chitosan endows these hydrogels with outstanding antibacterial performance against *** and ***,making them ideal candidates for use in wearable *** features allow for a practical approach to monitor full-range human motion using a single device with a simple structure.

关键词： porous hydrogels antibacterial performances wearable pressure sensors full-range human motion chitosan