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Positive- and Zero-Sequence Impedance estimation of YNyn0+d-Connected Main Power Transformers in Wind Power Applications

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CSee Journal of Power and energy Systems 2021年第1期7卷 57-65页

作者： Franklin l.Quilumba Robert e.Jimerson Ken Swift Rafael Garc´ıa with Oncor electric Delivery Fort WorthTX 76102 USA

With the increased penetration of non-conventionalrenewable energy resources, such as wind power plants (WPPs),into the power system, a lot of interest has been placed on studyingtheir impact for system protection, planning and operationsto ensure continued reliability of the electric grid. The impactof WPPs on the grid is typically identified during generationinterconnection studies. One of the challenges faced by protectionand planning engineers, at an early stage in this process, isthat many of the studies involving these power plants must beperformed without specific data available because the equipmentis not built yet. Among all the needed data, a particular interest inthis study is placed on the positive- and zero-sequence impedancesof the main power transformer (MPT) that interconnects a windpower plant to the transmission system due to its contribution toshort-circuit current during ground faults. The most commonlyfound in practice MPT winding configurations is a high-voltagewinding in wye with neutral bushing;a low-voltage windingin wye with neutral bushing without phase shift between thesewindings, and a stabilizing tertiary winding connected in deltathat is not designed for external loading designated as YNyn0+***, this paper proposes a methodology to estimate the sequenceimpedances of YNyn0+d transformers from a statistical point ofview applying clustering and regression analyses on existing MPTtest report data.

关键词： Positive-and zero-sequence impedance estimation power transformers short-circuit analysis threewinding transformer with buried tertiary wind power integration

Novel heating-and deformation-induced phase transitions and mechanical properties for multicomponent Zr_(50)M_(50),Zr_(50)(M,Ag)_(50)and Zr_(50)(M,Pd)_(50)(M=Fe,Co,Ni,Cu)amorphous alloys

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Journal of Materials Science & Technology 2022年第9期104卷 109-118页

作者： J.Ding A.Inoue F.l.Kong S.l.Zhu Y.l.Pu e.Shalaan A.A.Al-Ghamdi A.l.Greer School of Materials Science and engineering Tianjin UniversityTianjin 300072China International Institute of Green Materials Josai International UniversityTogane 283-8555Japan Institute of Massive Amorphous Alloy Science China University of Mining TechnologyXuzhou 221116China Department of Physics King Abdulaziz UniversityJeddah 22254Saudi Arabia MISiS National University of Science and TechnologyMoscow 119049Russia School of Materials Science and engineering Lanzhou Jiaotong UniversityLanzhou 730070China Department of Materials Science and Metallurgy University of CambridgeCambridge CB30FSUK

Multicomponent alloys of Zr_(50)M_(50),Zr_(50)(M,Ag)_(50)and Zr_(50)(M,Pd)_(50)(M=Fe,Co,Ni,Cu)can be melt-spun to obtain amorphous *** maximum thickness for fully amorphous ribbons varies with composition in the range 34-53μ*** contrast,fully amorphous ribbons are not obtainable for binary Zr_(50)Ni_(50)or ternary Zr_(50)(Ni,Cu)_(50)***-induced crystallization occurs through:two stages of amorphous[am]→[~(am')+B2]→[B2+B33]for Zr_(50)M_(50);and[am]→[am'+B2]→[B2+AgZr]for Zr_(50)(M,Ag)_(50);and a single stage of[am]→[B2]for Zr_(50)(M,Pd)_(50),while no B2 phase is formed for the binary and ternary Zr_(50)Q_(50)(Q=Ni or/and Cu)***-spun amorphous ribbons have good bending ***,Zr_(50)M_(50)ribbons in tension show 0.22-0.28%plastic elongation and work-hardening(the yield stress is~820 MPa,the fracture stress is~1200 MPa).When cold-rolled at room temperature to 30%reduction in thickness,Zr_(50)M_(50)ribbons show 10%increase in hardness,while retaining good bending ***-rolling induces precipitation of spheroidal B2 and irregular B33 particles,while deformation in tension induces B2,B33 and also plate-like monoclinic *** B2 and B33 particles form by polymorphic transformation,and include a high density of internal *** novel deformationinduced precipitation has not been recognized for any Zr_(50)Q_(50)binary or ternary *** new multicomponent systems are encouraging for future progress as structural amorphous alloys.

关键词： Multicomponent Microstructure Mechanical properties Phase transition Amorphous alloy

Rietveld refinement and optical properties of SrWO_4:eu^(3+) powders prepared by the non-hydrolytic sol-gel method

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Journal of Rare earths 2015年第2期33卷 113-128页

作者： P.F.S.Pereira I.C.Nogueira e.longo e.J.Nassar I.l.V.Rosa l.S.Cavalcante Chemistry Institute University of the State of Sao Paulo Julio de Mesquita Filho-UNESP Francisco DegniAraraquara-SP 14800-900 Brazil lIeC-Chemistry Department Federal University of Sao Carlos Via Washington Luis Km 235Sao Carlos-SP 13565-905 Brazil University of Franca-UNIFRAN Via Dr.Armando Sales de OliveiraNo.201 Franca-SP 14404-600 Brazil CCN-DQ-GeRATeC University of the State of Piauí Joao Cabral 2231 P.O.Box 391Terezina PI 64002-150 Brazil

We investigated the effect of annealing time on the structure and optical properties of Sr WO4：eu^3＋ powders prepared by the non-hydrolytic sol-gel method and heat treated at 800 ℃ for 2,4,8 and 16 *** and differential thermal analyses revealed that Sr WO4：eu^3＋ powders were obtained at about 800 ℃.X-ray diffraction patterns and Rietveld refinement data confirmed that all powders had a scheelite-type tetragonal ***-Raman and Fourier transform infrared spectra indicated structural order at short range and anti-symmetric stretching vibrations of O-W-O bonds associated with tetrahedral[WO4]*** properties were investigated by ultraviolet-visible（UV-vis）diffuse reflectance,and photoluminescence（Pl）data which provided the evolution of quantum efficiency（η）and lifetime（τ）.UV-vis spectroscopy evidenced intermediate energy levels within the band gap of Sr WO4：eu^3＋ *** properties validated that the eu^3＋ electric-dipole（^5D0→^7F2）transition in Pl emission spectra was dominant which proved that eu^3＋ ions were positioned in a site without an inversion center.[（^5D0→^7F2）/（^5D0→^7F1）]band ratios showed that eu^3＋ ions were located in a low symmetry *** Pl emission,ηandτproved the dependence on the annealing time in the behavior of Sr WO4：eu3＋powders with a higher relative emission Pl intensity as well as higherηandτvalues related to other samples when heat treated at 800℃ for 8 h.

关键词： SrWO4 Rietveld refinement optical band gap eu^(3+) +-rare earth luminescence

Kinetics of the Oxidative Dehydrogenation of Propane over a VMgO Catalyst

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Journal of Natural Gas Chemistry 2002年第1期11卷 33-42页

作者： l.late e.A.Blekkan DepartmentofChemicalegineering NorwegianUniversityofScienceandTechnology（NTNU）N－7491TrondheimNorway DepartmentofChemicalegineering NorwegianUniversityofScienceandTechnology（NTNU）N－7491TrondheimNor

The reaction kinetics of the oxidative dehydrogenation of propane was studied at 475-550°C over a VMgO catalyst. Vanadium-magnesium-oxides are among the most selective and active catalysts for the dehydrogenation of propane to propylene. Selectivity to propylene up to about 60% was obtained at 10% conversion, but the selectivity decreased with increasing conversion. No oxygenates were detected, the only by-products were CO and CO2. The reaction rate of propane was found to be first order in propane and close to zero order in oxygen, which is in agreement with a Mars van Krevelen mechanism with the activation of the hydrocarbon as the rate determining step. The activation energy of the conversion of propane was found to be 122±6 kJ/mol.

关键词： propane oxidative dehydrogenation VMgO kinetics

Two Cyclic Peptides Produced by the endophytic Fungus # 2221 from Castaniopsis fissa on the South China Sea Coast

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Chinese Chemical letters 2005年第2期16卷 219-222页

作者： WenQingYIN JieMingZOU ZhiGangSHe l.l.P.Vrijmoed e.B.GarethJones YongChenglIN DepartmentofA_ppliedChemistry ZhongshanUniversityGuangzhou510275 DepartmentofAppliedChemistry ZhongshanUniversityGuangzhou510275／／GuilinSanjinPharmaceuticalCo.Ltd.Guilin541004／／DepartmentofchemistryandchemicalengineeringGuangxiNormalUniversityGuilin5411004 GuilinSanjinPharmaceuticalCo.ltd. Guilin541004 DepartmentofBiologyandChemistry CityUniversityofHongKongHongKong

New cyclic peptides 1 and 2 were isolated from the endophytic fungus #2221 fromCastaniopsis fissa on the south China sea coast. By 2D NMR methods and chiral HPlC technique,their structures were elucidated as cyclo (l-... 详细信息

关键词： endophytic fungus cyclic peptides metabolite.

Optimizing outcomes for patients with gastric cancer peritoneal carcinomatosis

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World Journal of Gastrointestinal Oncology 2018年第10期10卷 282-289页

作者： Jennifer l leiting Travis e Grotz Division of Hepatobiliary and Pancreas Surgery Mayo Clinic

Peritoneal carcinomatosis (PC) from gastric cancer has traditionally been considered a terminal progression of the disease and is associated with poor survival out-comes. Positive peritoneal cytology similarly worsens the survival of patients with gastric cancer and treatment options for these patients have been limited. Recent ad-vances in multimodality treatment regimens have led to innovative ways to care for and treat patients with this disease burden. One of these advances has been to use neoadjuvant therapy to try and convert patients with positivecytologyorlow-volume PC to negative cytolo-gy with no evidence of active peritoneal *** strategies include the use of neoadjuvant systemic chemotherapy alone,using neoadjuvant laparoscopic heated intraper itoneal chemotherapy(NlHIPeC)after systemic chemotherapy,or using neoadjuvant intra-peritoneal and systemic chemother apy(NIPS)in a bi-dir ectional manner. For patients with higher volume PC,cytoreductive surgery (CRS) and hyperthermic intrape-ritoneal chemotherapy(HIPeC)have been mainstays of treatment. When used together, CRS and HIPeC can improve overall outcomes in properly selected patients,but overall survival outcomes remain unacceptably *** extent of peritoneal disease, commonly measured by the peritoneal carcinomatosis index (PCI), and the com-pleteness of cytor eduction,has been shown to greatly impact outcomes in patients undergoing CRS and *** uses of NlHIPeC and NlHIPeC plus NIPS have both been shown to decrease the PCI and thus increase the opportunity for complete cytoreduction. Newer therapies like pressurized intraperitoneal aerosol chemother apy and immunotherapy, such as catumaxomab, along with improved systemic chemotherapeutic regimens, are being explored with great *** is exciting progress being made in the management of PC from gastric can-cer and its’ treatment is no longer futile.

关键词： Peritoneal carcinomatosis index Peritoneal carcinomatosis Gastric cancer Cytoreductive surgery Heated intraperitoneal chemotherapy Neoadjuvant intraperitoneal and systemic chemotherapy

Digital twin intelligent system for industrial internet of things-based big data management and analysis in cloud environments

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Virtual Reality & Intelligent Hardware 2022年第4期4卷 279-291页

作者： Christos l.STeRGIOU Kostas e.PSANNIS Department of Applied Informatics University of MacedoniaGreece

This work surveys and illustrates multiple open challenges in the field of industrial Internet of Things(IoT)-based big data management and analysis in cloud *** arising from the fields of machine learning in cloud infrastructures,artificial intelligence techniques for big data analytics in cloud environments,and federated learning cloud systems are ***,reinforcement learning,which is a novel technique that allows large cloud-based data centers,to allocate more energy-efficient resources is ***,we propose an architecture that attempts to combine the features offered by several cloud providers to achieve an energy-efficient industrial IoT-based big data management framework(eeIBDM)established outside of every user in the *** data can be integrated with techniques such as reinforcement and federated learning to achieve a digital twin scenario for the virtual representation of industrial IoT-based big data of machines and room ***,we propose an algorithm for determining the energy consumption of the infrastructure by evaluating the eeIBDM ***,future directions for the expansion of this research are discussed.

关键词： Machine learning IoT Big data Cloud computing Management Analytics Digital twin Scenario energy efficiency

Quantum-dot microlasers based on whispering gallery mode resonators

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light(Science & Applications) 2021年第5期10卷 785-795页

作者： A.e.Zhukov N.V.Kryzhanovskaya e.l.Moiseev M.V.Maximov laboratory of quantum optoelectronics National Research University Higher School of EconomicsKantemirovskaya 3ASt.Petersburg 194100Russia Nanophotonics laboratory Alferov UniversityKhlopina 8/3St.Petersburg 194021Russia

The subject of this paper is microlasers with the emission spectra determined by the whispering gallery *** to the total internal reflection of light on the sidewalls,a high Q-factor is achieved until the diameter is comparable to the *** light emission predominantly occurs in the plane of the structure,which facilitates the microlaser integration with other *** focus on microdisk lasers with various types of the In(Ga)As quantum dots(QDs).Deep localization of charge carriers in spatilly separated regions suppresses the lateral diffusion and makes it possible to overcome the undesirable effect of non-adiative recombination in deep ***,using conventional epitaxial structures and relatively simple post-growth processing methods,it is possible to realize small microlasers capable of operating without temperature stabilization at elevated *** low sensitivity of QDs to epitaxial and manufacturing defects allows fabricating microlasers using IIV heterostructures grown on silicon.

关键词： Quantum mode overcome

A new currency for mutualism?Fungal endophytes alter antioxidant activity in hosts responding to drought

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Fungal Diversity 2012年第3期54卷 39-49页

作者： Cyd e.Hamilton Taryn l.Bauerle MTT Agrifood and Biotech Plant Production UnitJokioinenFinland Cornell University HorticultureIthacaNYUSA

Fungal endophytes have significant effects on host performance including but not limited to changes in reproductive output,as well as,biotic and abiotic stress *** ultimate mechanisms for resistance to herbivory have been documented in a number of fungal-plant symbiota and involve the production of alkaloids by the *** have thus been defined as a currency responsible for increased host resistance to *** provide support for the hypothesis that another currency may be responsible for increased host tolerance to abiotic stress resulting from endophyte colonization;namely *** report comparatively higher activity of antioxidants in endophyte colonized hosts resulting from abiotic stress and propose antioxidants are another currency via which mutualistic interactions between fungal endophytes and their hosts can *** recognize fungal endophyte interactions are diverse and complex and include antagonisms,commensalisms,and mutualisms.

关键词： Symbiont Stress epichloe Neotyphodium Stress tolerance Reactive oxygen species