检索结果-南通市图书馆

^1H NMR Quantification of DHA and EPA in Fish Oil

在线全文

学校读者我要写书评

暂无评论

Journal of Ocean University of China 2020年第5期19卷 1193-1197页

作者： lv Jinxiao WANG Cong ZHANG Xiuli lv Zhihua YU Mingming School of Medicine and Pharmacy Ocean University of ChinaQingdao 266003China Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology Qingdao 266003China Key Laboratory of Glycoscience&Glycotechnology of Shandong Province Qingdao 266003China Key Laboratory of Marine Drugs Ministry of Education of ChinaQingdao 266003China

Fish oil is a popular nutritional product consumed in China. The beneficial effects of fish oil have been attributed to docosahexaenoic acid(DHA) and eicosapentaenoic acid(EPA). Hence, it is crucial to develop a rapid and precise method to determine the contents of EPA and DHA in fish oil. In this study, a rapid and accurate proton nuclear magnetic resonance method for the quantification of DHA and EPA was developed. Dimethyl terephthalate was selected as an internal standard, and the signals at 2.391 ppm for DHA and at 1.697 ppm for EPA were chosen for the quantification. Validation of the method was performed in terms of specificity, precision, and stability. The results indicated that the method was precise and in line with the China Food and Drug Administration guidance. The method has been successfully applied to characterize fish oil capsules obtained from four pharmaceutical companies. This study indicated that the rapid ~1H NMR method is suitable for the quality control of fish oil.

关键词： ^1H NMR EPA DHA fish oil quality control

Embedding Derivatives and Integration Operators on Hardy Type Tent Spaces

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2022年第6期38卷 1069-1093页

作者： Mao Fa WANG lv ZHOU School of Mathematics and Statistics Wuhan UniversityWuhan 430072P.R.China

In this paper,we completely characterize the positive Borel measuresμon the unit ball B_(n)such that the differential type operator R^(m)of order m∈N is bounded from Hardy type tent space HT_(q,α)^(p)(B_(n))into L^(s)(μ)for full range of p,q,s,α.Subsequently,the corresponding compact description of differential type operator R^(m)is also *** an application,we obtain the boundedness and compactness of integration operator J_(g)from HT_(q,α)^(p)(B_(n))toHT_(s,β)^(t)(B_(n)),and the methods used here are adaptable to the Hardy spaces.

关键词： Embedding derivative integration operator Hardy type tent space Carleson measure

Control of chiral-optical activities by magnetic field based on the transformation of achiral binary crystals into chiral ternary crystals

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第7期67卷 2300-2305页

作者： Zhiyan Chen Yan lv Wei Qin College of Physics Qingdao UniversityQingdao 266071China School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China Shandong Linuo Photovoltaic Hi-Tech Co. Ltd.Jinan 250100China

Multicomponent self-assembled chiral systems have attracted great attention due to their promising application in the area of spin-photonics and *** this work,through introducing an achiral third component into an achiral binary crystal,a chiral organic ternary crystal is fabricated,where both pronounced chiral-optical coupling and magnetic field dependence of chiral-optical activities are *** transformation of achiral structure into chiral structure generates a significant effect on the polarized state of light and the electron spin resonance ***,the coupling between circularly polarized photon and spin is observed in chiral ternary crystal with pronounced chiral orbit,where obvious magnetic field-transmissivity loop is ***,temperature could increase the magnitude of lattice parameters to lead to a larger helix radius to increase the chiral orbit ***,this work indicates that the further exploration of photon-chiral orbit-spin interactions in organic chiral ternary crystals is promising.

关键词： organic chiral ternary crystals chiral orbit chiral-optical activities magnetic field

Decentralized Bilateral Risk-based Self-healing Strategy for Power Distribution Network with Potentials from Central Energy Stations

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2023年第1期11卷 179-190页

作者： Chaoxian lv Rui Liang Yuanyuan Chai School of Electrical Engineering China University of Mining and TechnologyXuzhouChina School of Electrical Engineering Hebei University of TechnologyTianjinChina

Owing to potential regulation capacities from flexible resources in energy coupling,storage,and consumption links,central energy stations(CESs)can provide additional support to power distribution network(PDN)in case of power ***,existing research has not explicitly revealed the emergency response of PDN with leveraging multiple *** paper proposes a decentralized self-healing strategy of PDN to minimize the entire load loss,in which multi-area CESs’potentials including thermal storage and building thermal inertia,as well as the flexible topology of PDN,are reasonably exploited for service *** sake of privacy preservation,the co-optimization of PDN and CESs is realized in a decentralized manner using adaptive alternating direction method of multipliers(ADMM).Furtherly,bilateral risk management with conditional value-at-risk(CVaR)for PDN and risk constraints for CESs is integrated to deal with uncertainties from outage *** studies are conducted on a modified IEEE 33-bus PDN with multiple *** results illustrate that the proposed strategy can fully utilize the potentials of multi-area CESs for coordinated load *** effectiveness of the performance and behaviors’adaptation against random risks is also validated.

关键词： Power distribution network(PDN) central energy station(CES) bilateral risk management self-healing alternating direction method of multipliers(ADMM)

Multiple magnetic topologies in flux transfer events: THEMIS measurements

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2016年第8期59卷 1283-1293页

作者： lv LeiQi PU ZuYin XIE Lun School of Earth and Space Science Peking University Beijing 100871 China PKU/UCLA Joint Research Institute in Science and Engineering Peking University Beijing 100871 China

Flux transfer events （FTEs） are local transient magnetic reconnections at the magnetopause （MP） that provide channels for transport of solar wind energy and plasma into the magnetosphere （MSP）. All current theoretical models suggest that FTEs are open-flux ropes; however, global simulations show that they contain both open and closed magnetic fields. To clarify this to- pology, we analyzed 441 events observed by THEMIS and investigated their magnetic topologies. Only one type of open field line was detected in most magnetosheath （MSH） FTEs, independent of the polarity of the Bn bipolar signatures. Newly formed MSH field lines were also observed. In the all MP boundary layers FTEs and most MSP FTEs, multiple types of topologies were observed, irrelevant to the Bn bipolar polarity. Closed field lines were found in all MP boundary layers and MSP FTEs. Meanwhile very few boundary FTEs contained the newly formed MSH flux. In some situations, only closed field lines were seen in MSP FTEs, which are referred to as the fossil FTEs. These results, which largely differ from the traditional view, demonstrate the existence of complex magnetic topologies in FTEs. Based on these results, we propose a new 3D FTE picture to modify the current FTE models.

关键词： flux transfer events magnetic flux rope magnetic field topology magnetopause

Identity-based key distribution for mobile Ad Hoc networks

在线全文

学校读者我要写书评

暂无评论

Frontiers of Computer Science 2011年第4期5卷 442-447页

作者： Xixiang lv Hui LI Baocang WANG State Key Laboratory of Integrated Service Networks Xidian University Xi＇an 710071 China State Key Laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing 100049 China

An identity-based cryptosystem can make a special contribution to building key distribution and management architectures in resource-constrained mobile ad hoc networks since it does not suffer from certificate management problems. In this paper, based on a light- weight cryptosystem, elliptic curve cryptography （ECC）, we propose an identity-based distributed key-distribution protocol for mobile ad hoc networks. In this protocol, using secret sharing, we build a virtual private key generator which calculates one part of a user＇s secret key and sends it to the user via public channels, while, the other part of the secret key is generated by the user. So, the secret key of the user is generated collaboratively by the virtual authority and the user. Each has half of the secret information about the secret key of the user. Thus there is no secret key distribution problem. In addition, the user＇s secret key is known only to the user itself, therefore there is no key escrow.

关键词： key distribution Ad Hoc networks identity-based cryptography

Rational construction of graphene oxide with MOF- derived porous NiFe@C nanocubes for high-performance microwave attenuation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2016年第12期9卷 3671-3682页

作者： Zhihong Yang Hualiang lv Renbing WU College of Materials Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 211100 China Department of Materials Science Fudan University Shanghai 200433 China

Exploring lightweight microwave attenuation materials with strong and tunable wideband microwave absorption is highly desirable but remains a significant challenge. Herein, three-dimensional （3D） porous hybrid composites consisting of NiFe nanoparticles embedded within carbon nanocubes decorated on graphene oxide （GO） sheets （NiFe@C nanocubes@GO） as high-performance microwave attenuation materials have been rationally synthesized. The 3D porous hybrid composites are fabricated by a simple method, which involves one-step pyrolysis of NiFe Prussian blue analogue nanocubes in the presence of GO sheets. Benefiting from the unique structural features that exhibit good magnetic and dielectric losses as well as a proper impedance match, the resulting NiFe@C nanocubes@GO composites show excellent microwave attenuation ability. With a minimum reflection loss （RL） of -51 dB at 7.7 GHz at a thickness of 2.8 mm and maximum percentage bandwidth of 38.6% for RL 〈 -10 dB at a thickness of 2.2 mm, the NiFe@C nanocubes@GO composites are superior to the previously reported state-of-the-art carbon-based microwave attenuation materials.

关键词： hybrid dielectric loss magnetic loss microwave attenuation

Structural and Mechanical Characterization ofAtrina Pectinata and Freshwater Mussel Shells

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2015年第2期12卷 276-284页

作者： Jianlu lv Yonggang Jiang Deyuan Zhang School of Mechanical Engineering and Automation Beihang University Xueyuan Road No. 37 Haidian District Beij'ing 1 00191 China International Research Institute for Multidisciplinary Science Beihang University Xueyuan Road No. 37 Haidian District Belling 100191 China

The microstructures ofAtrina pectinata and freshwater mussel shells are investigated by optical microscopy and scanning electron microscopy. The mechanical properties of these shells are characterized by nanoindentation and three-point bending tests. Results show that both shells possess a prismatic microstructure mainly composed of columnar crystals and an organic matrix. The fracture toughness of the prismatic structure of Atrina pectinata and freshwater mussel are approximately 1.15 MPa.m1/2 and 0.87 MPa.m1/2, respectively, while the fracture toughness of natural calcite is approximately 0.2 MPa.m1/2. Calculated results from indentations agree with those obtained from the three-point bending tests. The columnar crystal material shows excellent fracture toughness due to grain refinement. In addition, the organic matrix of the prismatic layer can arrest cracks, and thereby improves the fracture toughness.

关键词： shell prismatic fracture toughness organic matrix crack

Vehicle-to-grid service development logic and management formulation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2019年第4期7卷 935-947页

作者： Lefeng SHI Tong lv Yandi WANG School of Economics and Management Chongqing Normal UniversityChongqing 401331China School of Electrical Engineering Shandong UniversityJinan 250061China

Vehicle-to-grid(V2G)is regarded as the effective way to reconcile contradictions between an electric power system and electric vehicles(EVs).A lot of research has been carried out to affect this,often based on different technical and trade model *** value of theresearch is dependent on how reasonable the assumptions it makes *** paper presents a framework for analyzing V2G service development from a coevolutionary perspective in which the interactive relation between the diffusion of EVs and the upgrade of the distribution grid system is considered.A V2G service development logic and its management formulation are put ***,the motivations and contradictions of developing V2G services are *** a development phase division of the V2G services is proposed in view of the coevolution relation between the grid upgrade and the development of the ***,taking into account the characteristics of each phase,the physical trade structures and corresponding management hierarchies,management relations as well as management measures,are *** paper provides a new perspective of V2G service development,answers the core question on how to make the V2G vision come true in synergy with the development of EVs,and gives some advice on future V2G management paradigms.

关键词： Electric vehicle Vehicle-to-grid service Smart grid Aggregator