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Chemical diversity and biological function of indolediketopiperazines from marine-derived fungi

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Marine Life Science & Technology 2020年第1期2卷 31-40页

作者： jin cao Bin-Gui Wang Key Laboratory of Experimental Marine Biology Institute of OceanologyChinese Academy of Sciences and Laboratory of Marine Biology and BiotechnologyQingdao National Laboratory for Marine Science and TechnologyQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China

Natural products from marine-derived fungi have attracted considerable attention in the recent two *** are one of the most important classes of marine natural products,mainly discovered from the fungal genera Penicillium,Aspergillus and *** compounds span a wide range of chemical structures and *** review summarizes 155 indolediketopiperazines that were discovered from marine-derived fungi from 2000 to early 2019 and primarily focuses on their chemical diversity and biological function.

关键词： Indolediketopiperazines Marine-derived fungi Natural products Chemical diversity Biological function

Non-dominated sorting quantum particle swarm optimization and its application in cognitive radio spectrum allocation

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Journal of Central South University 2013年第7期20卷 1878-1888页

作者： GAO Hong-yuan cao jin-long College of Information and Communication Engineering Harbin Engineering University Harbin 150001 China School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

In order to solve discrete multi-objective optimization problems, a non-dominated sorting quantum particle swarm optimization (NSQPSO) based on non-dominated sorting and quantum particle swarm optimization is proposed, and the performance of the NSQPSO is evaluated through five classical benchmark functions. The quantum particle swarm optimization (QPSO) applies the quantum computing theory to particle swarm optimization, and thus has the advantages of both quantum computing theory and particle swarm optimization, so it has a faster convergence rate and a more accurate convergence value. Therefore, QPSO is used as the evolutionary method of the proposed NSQPSO. Also NSQPSO is used to solve cognitive radio spectrum allocation problem. The methods to complete spectrum allocation in previous literature only consider one objective, i.e. network utilization or fairness, but the proposed NSQPSO method, can consider both network utilization and fairness simultaneously through obtaining Pareto front solutions. Cognitive radio systems can select one solution from the Pareto front solutions according to the weight of network reward and fairness. If one weight is unit and the other is zero, then it becomes single objective optimization, so the proposed NSQPSO method has a much wider application range. The experimental research results show that the NSQPS can obtain the same non-dominated solutions as exhaustive search but takes much less time in small dimensions; while in large dimensions, where the problem cannot be solved by exhaustive search, the NSQPSO can still solve the problem, which proves the effectiveness of NSQPSO.

关键词： cognitive radio spectrum allocation multi-objective optimization non-dominated sorting quantum particle swarmoptimization benchmark function

A method of autonomous orbit determination for satellite using star sensor

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Science China(Physics,Mechanics & Astronomy) 2005年第3期48卷 268-281页

作者： MA Jianbo XU jin cao Zhibin Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

In this paper a method of autonomous orbit determination using star sensor is studied. By building relatively consummate dynamical models which simulate attitude motion of satellite and observation from satellite to background stars, the simulant computation of this method is executed, and it is shown that the method of autonomous orbit determination is feasible. Academic and calculation analyses have been done for the relation between the direction of star sensor with respect to satellite-body coordinate system and the accuracy of autonomous orbit determination.

关键词： autonomous orbit determination of satellite, star sensor, attitude of satellite.

Full-frame Data Reduction Method:A Data Mining Tool to Detect the Potential Variations in Optical Photometry

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Research in Astronomy and Astrophysics 2023年第5期23卷 110-141页

作者： Zhi-Bin Dai Hao Zhou jin cao Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 101408China School of Information Science and Engineering of Yunnan University Kunming 650500China

A Synchronous Photometry Data Extraction(SPDE)program,performing indiscriminate monitoring of all stars appearing in the same field of view of an astronomical image,is developed by integrating several Astropy affiliated packages to make full use of time series observed by traditional small/medium aperture ground-based *** complete full-frame stellar photometry data reductions implemented for the two time series of cataclysmic variables:RX J2102.0+3359 and Paloma J0524+4244 produce 363 and 641 optimal light curves,respectively.A cross-identification with SIMBAD finds 23 known stars,of which 16 are red giant-/horizontal-branch stars,2 W UMa-type eclipsing variables,2 program stars,an X-ray source and 2 Asteroid Terrestrial-impact Last Alert System *** on the data products from the SPDE program,a follow-up light curve analysis program identifies 32 potential variable light curves,of which 18 are from the time series of RX J2102.0+3359,and 14 are from that of Paloma J0524+*** are preliminarily separated into periodic,transient,and peculiar *** querying for the 58 VizieR online data catalogs,their physical parameters and multi-band brightness spanning X-ray to radio are compiled for future analysis.

关键词： catalogs-stars fundamental parameters-stars variables general-methods data analysis-techniques photometric

Transitivity of varietal hypercube networks

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Frontiers of Mathematics in China 2014年第6期9卷 1401-1410页

作者： Li XIAO jin cao Jun-Ming XU School of Mathematical Sciences University of Science and Technology of ChinaWentsun Wu Key Laboratory of CAS Hefei 230026 China

The varietal hypercube VQn is a variant of the hypercube Qn and has better properties than Qn with the same number of edges and vertices. This paper proves that VQn is vertex-transitive. This property shows that when VQn is used to model an interconnection network, it is high symmetrical and obviously superior to other variants of the hypercube such as the crossed cube.

关键词： Combinatorics graph transitivity varietal hypercube network

Internal Stress Distribution Model of the Magnetomechanical Hysteresis of Fe-Cr-Al Based Alloys

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Journal of Materials Science & Technology 2011年第5期27卷 471-474页

作者： Renrong Lin Wei jin Mingzhou cao Rui Yang Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The damping capacities of Fe-13Cr-6AI, Fe-12Cr-1Mo-6AI and Fe-12Cr-1Mn-6Al （at.%） alloys as a function of strain-amplitude tested in a given static load are characterized in the 3-point bending deformation mode. After being modified, Smith-Birchak model is applied to describe the results. It is shown that the modified model agrees with the experimental data much better than the original one. Finally, the influences of stress factors on the damping capacity of the alloys are analyzed.

关键词： Magnetomechanical damping Static load Smith-Birchak model 3-point bending

Magnetic resonance imaging for chronic pain:diagnosis,manipulation,and biomarkers

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Science China(Life Sciences) 2021年第6期64卷 879-896页

作者： Yiheng Tu jin cao Yanzhi Bi Li Hu CAS Key Laboratory of Mental Health Institute of PsychologyBeijing 100101China Department of Psychology University of Chinese Academy of SciencesBeijing 100101China Department of Psychiatry Massachusetts General Hospital and Harvard Medical SchoolBoston 02129USA Department of Pain Management The State Key Clinical Specialty in Pain MedicineThe Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510260China

Pain is a multidimensional subjective experience with biological,psychological,and social *** acute pain can be a warning signal for the body to avoid excessive injury,long-term and ongoing pain may be developed as chronic *** are more than 100 million people in China living with chronic pain,which has raised a huge socioeconomic *** the mechanisms of pain and developing effective analgesia approaches are important for basic and clinical ***,with the development of brain imaging and data analytical approaches,the neural mechanisms of chronic pain have been widely *** the first part of this review,we briefly introduced the magnetic resonance imaging and conventional analytical approaches for brain imaging ***,we reviewed brain alterations caused by several chronic pain disorders,including localized and widespread primary pain,primary headaches and orofacial pain,musculoskeletal pain,and neuropathic pain,and present meta-analytical results to show brain regions associated with the pathophysiology of chronic ***,we reviewed brain changes induced by pain interventions,such as pharmacotherapy,neuromodulation,and ***,we reviewed emerging studies that combined advanced machine learning and neuroimaging techniques to identify diagnostic,prognostic,and predictive biomarkers in chronic pain patients.

关键词： chronic pain magnetic resonance imaging biomarkers machine learning

Performance of large-diameter pneumatic down-the-hole (DTH) hammers: A focus on influences of the hammer structure

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Petroleum Science 2023年第4期20卷 2399-2412页

作者： Pin-Lu cao Hong-Yu cao jin-E cao Cheng-Da Wen Bao-Yi Chen Shan-Shan Yao College of Construction Engineering Jilin UniversityNo.938 Ximinzhu StrChangchunJilin130061China

Pneumatic down-the-hole (DTH) hammer has been extensively used in air drillings through hard and ultra-hard geological formations. Numerical modeling can offer close observation on the working behaviors by visualizing internal pressure status as well as provide reliable performance predictions for large-diameter DTH hammers to which conventional empirical and experimental approaches cannot be applied. In this study, CFD simulations coupled with dynamic meshing are utilized to simulate the air flow and piston movement inside the large-diameter DTH hammers. The numerical modeling scheme is verified against a theoretical model published in literature. Effects of structural parameters on hammer performance, including piston mass, piston upper-end diameter, piston groove diameter, and lengths of intake and exhaust stroke in both front and rear chambers, are analyzed in detail by virtue of sets of numerical simulations. The simulations suggest that changing the intake stroke of front chamber has a negligible influence on hammer performance while increasing the piston groove would lower all the four indicators of hammer performance, including impact energy, impact frequency, maximum stroke, and air consumption rate. Changing the other structural parameters demonstrates mixed effects on the performance indicators. Based on the numerical simulations, a large GQ-400 DTH hammer has been designed for reduced air consumption rate and tested in a field drilling practice. The air drilling test with the designed hammer provided a penetration rate 1.7 times faster than that of conventional mud drilling.

关键词： Pneumatic down-the-hole(DTH)hammer Computational fluid dynamics Dynamic mesh Gas turbulent flow Piston impact performance

Experimental and Numerical Study of Non-Premixed Dimethyl Ether/Methane-Air Hot Flame at Elevated Pressures

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Journal of Thermal Science 2023年第1期32卷 401-413页

作者： cao jin ZHOU Xun ZHANG Rui YANG Shenghua LIU Dong MIIT Key Laboratory of Thermal Control of Electronic Equipment School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing 210094China Advanced Combustion Laboratory School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing210094China

Methane has a narrow range of flammable limits,low flame speed and poor ignition characteristics,which limit its utilization in internal combustion ***,this issue can be remedied through the use of CH_(4)/DME blends,because DME has better ignition and combustion *** this study,the effects of pressure and blending ratio on the combustion characteristics of CH_(4)/DME blended fuels were investigated by using a high-pressure diffusion counterflow system,a constant volume combustion bomb,and CHEMKIN *** reaction pressures are 0.1 MPa,0.2 MPa,0.3 MPa,and the blending ratios are 100%DME,75%DME+25%CH_(4),50%DME+50%CH_(4)and 25%DME+75%CH_(4)(mol%).The results show that the laminar flame speed,flame temperature,and extinction limit of CH_(4)/DME blended fuel decrease as the CH_(4)blending ratio or pressure ***_(4)addition and increasing pressure both lead to the competition for OH and H radicals between CH_(4)and ***,the increase of CH_(4)mole fraction can also increase the path flux of CH_(4)+H=CH_(3)+H_(2),while the increase of pressure can decrease this path ***,increasing pressure can promote all reaction processes and reaction rates.

关键词： counterflow high-pressure DME CH4 extinction limit