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Research in Astronomy and Astrophysics 2017年第5期17卷 31-38页

作者： Diana petrova Kjurkchieva velimir Angelov Popov Sunay Ibryamov Ibryamov Doroteya Lyubenova vasileva Nikola Ivanov petrov Department of Physics Shumen University115 Universitetska Str.9712 ShumenBulgaria IRIDA Observatory Rozhen NAOBulgaria Institute of Astronomy and NAO Bulgarian Academy of Sciences72 Tsarigradsko Shose Blvd.1784 SofiaBulgaria

Photometric observations in Sloan g′and i′bands of four W UMa binaries, v796 Cep,v797 Cep, CSS J015341.9＋381641 and NSvS 3853195, are presented. Our observations showed that CSS J015404.1＋382805 and NSvS 3853195 are the same star. We determined the initial epochs T_0 of all targets and found improved values for the period of NSvS 3853195. The light curve solutions of our data revealed that the components of each target are almost the same in terms of mass, temperature,radius and luminosity. The stellar components are G and K spectral types and undergo partial *** systems have barely-overcontact configurations and can be classified as H subtype W UMa *** established that the relation between the luminosity ratio l_2/l_1 and mass ratio q of our targets is approximately l_2/l_1 = q^（1.5）.

关键词： stars: binaries: eclipsing -- stars: fundamental parameters -- stars: individual (v796 Cep,v797 Cep CSS J015341.9+381641 NSvS 3853195)

Pancreatic enzymes and abdominal adipose tissue distribution in new-onset prediabetes/diabetes after acute pancreatitis

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World Journal of Gastroenterology 2021年第23期27卷 3357-3371页

作者： Juyeon Ko Loren Skudder-Hill Jaelim Cho Sakina H Bharmal Maxim S petrov School of Medicine University of AucklandAuckland 1142New Zealand

BACKGROUND New-onset prediabetes/diabetes after acute pancreatitis(NODAP)is the most common sequela of pancreatitis,and it differs from type 2 prediabetes/diabetes mellitus(T2DM).AIM To study the associations between circulating levels of pancreatic amylase,pancreatic lipase,chymotrypsin and fat phenotypes in NODAP,T2DM,and *** Individuals with NODAP(n=30),T2DM(n=30),and sex-matched healthy individuals(n=30)were *** fat phenotypes(intra-pancreatic fat,liver fat,skeletal muscle fat,visceral fat,and subcutaneous fat)were determined using the same magnetic resonance imaging protocol and scanner magnet strength for all ***-way analysis of covariance,linear regression analysis,and relative importance analysis were *** Intra-pancreatic fat deposition(IPFD)was higher in NODAP(9.4%±1.8%)and T2DM(9.8%±1.1%)compared with healthy controls(7.8%±1.9%)after adjusting for covariates(P=0.003).Similar findings were observed in regards to visceral fat volume(P=0.005),but not subcutaneous fat volume,liver fat,or skeletal muscle *** IPFD(β=-2.201,P=0.023)and visceral fat volume(β=-0.004,P=0.028)were significantly associated with circulating levels of pancreatic amylase in NODAP,but not in T2DM or healthy *** the five fat phenotypes,IPFD explained the highest amount of variance in pancreatic amylase concentration(R2=15.3%out of 41.2%).None of the phenotypes contributed meaningfully to the variance in pancreatic lipase or *** Both NODAP and T2DM are characterized by increased IPFD and visceral fat ***,only NODAP is characterized by significant inverse associations between the two fat phenotypes and pancreatic amylase.

关键词： Amylase Lipase Chymotrypsin Pancreatitis Diabetes Intra-pancreatic fat visceral fat Liver fat

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非金属原料的重要作用和特殊性质

矿产综合利用 1986年第4期 93-98页

作者： v·P·petrov 汪镜亮

非金属组原料是划分为两个大组——燃料矿物和金属矿石后,作为“剩余”部分而出现的。当然,这两个大组和非金属组要清楚区分开是非常困难的。例如,琥珀、沥青岩或矿物石蜡是燃料矿物,而同时也可将它们视作典型的非金属原料。钛矿石在... 详细信息

非金属组原料是划分为两个大组——燃料矿物和金属矿石后,作为“剩余”部分而出现的。当然,这两个大组和非金属组要清楚区分开是非常困难的。例如,琥珀、沥青岩或矿物石蜡是燃料矿物,而同时也可将它们视作典型的非金属原料。钛矿石在较小程度上

关键词：沥青岩金属矿石粘土类层状硅酸盐矿物对原料工业工业矿物矿床形成铝土矿资源碳酸盐岩

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微带平衡放大器用的混合集成电路的研制

微纳电子技术 1979年第6期 42-45页

作者： G.v.petrov 孙中元

宽带平衡放大器用的混合集成电路(HIC)在超高频范围内已广泛地用于各种收发机上,因为它能使我们在输入和输出端获得低电压驻波比、线性更好的相位-频率特性以及比单级放大器更大的动态范围。在宽带平衡放大器的研制中要解决的主要问题... 详细信息

宽带平衡放大器用的混合集成电路(HIC)在超高频范围内已广泛地用于各种收发机上,因为它能使我们在输入和输出端获得低电压驻波比、线性更好的相位-频率特性以及比单级放大器更大的动态范围。在宽带平衡放大器的研制中要解决的主要问题是选择晶体管的输入和输出端的匹配电路,用以提供均匀的振幅-频率性能和在宽带内使源和负载之间匹配。本文中我们讨论采用具有不同Q因子的短线定向耦合器(SDC)作为耦合器的微带平衡超高频放大器混合集成电路(HIC)的研究,并考虑到晶体管的稳定性。

关键词：混合集成电路超高频宽带匹配网络 HIC 微带线 SDC 厘米波(10厘米-1厘米) 微波频率平衡放大器推挽放大器单级放大器

Synthesis, X-ray structure and luminescent properties of Sm^(3+) ternary complex with novel heterocyclic β-diketone and 1,10-phenanthroline (Phen)

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Journal of Rare Earths 2011年第8期29卷 719-722页

作者： Ilya v. Taydakov Boris E. Zaitsev Sergey S. Krasnoselskiy Zoya A. Starikova G. S. petrov Institute of Plastics JSC Perovskiy proezd 35 Moscow 111024 Russian Federation People's Friendship University of Russia A. N. Nesmeyanov Institute of Organoelement Compounds Russian Academy of Sciences

A new neutral ternary samarium complex Sm（Phen）HL3 in which Phen is 1,10-phenanthroline and HL is （1,3-bis（1,3-dimethyl-1H-pyrazol-4-yl）-1,3-propanedione） was synthesized. Molecular structure of this complex was determined by X-ray diffraction. Under Uv-light this complex is demonstrated bright red luminescence （λmax=647 nm）, which was corresponding to the electric dipole 4G5/2→6H9/2 transition in Sm3＋ ion. Uv-absorption, excitation and emission spectra of the title compound were investigated.

关键词： samarium pyrazole β-diketone crystal structure photoluminescence rare earths

Upper Hybrid Resonance RADAR Scattering Diagnostics of Small Scale Turbulence in FT-1 Tokamak

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中国核科技报告 1999年第S4期 384-384页

作者： A.D.Gurchenko,E.Z.Gusakov,M.M.Larionov,K.M.Novik,Yu.v.petrov,A.N.Saveliev,v.L.Selenin,A.Yu.Stepanov Ioffe Physico-Technical Institute Politekhnicheskaya 26 194021 St.Petersburg Russia Ioffe Physico-Technical Institute Politekhnicheskaya 26 194021 St.Petersburg Russia Ioffe Physico-Technical Institute Politekhnicheskaya 26 194021 St.Petersburg Russia Ioffe Physico-Technical Institute Politekhnicheskaya 26 194021 St.Petersburg Russia Ioffe Physico-Technical Institute Politekhnicheskaya 26 194021 St.Petersburg Russia Ioffe Physico-Technical Institute Politekhnicheskaya 26 194021 St.Petersburg Russia Ioffe Physico-Technical Institute Politekhnicheskaya 26 194021 St.Petersburg Russia Ioffe Physico-Technical Institute Politekhnicheskaya 26 194021 St.Petersburg Russia

The new diagnostic technique, utilizing RADAR microwave scattering in the Upper Hybrid Resonance (UHR) has been developed and applied for study of spontaneous magnetic field and density turbulence in the FT-1 tokamak.... 详细信息

关键词： Upper Hybrid Resonance RADAR Scattering Diagnostics of Small Scale Turbulence in FT-1 Tokamak FT

All-optical generation of static electric field in a single metal-semiconductor nanoantenna

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Light(Science & Applications) 2023年第11期12卷 2350-2362页

作者： Yali Sun Artem Larin Alexey Mozharov Eduard Ageev Olesia Pashina Filipp Komissarenko Ivan Mukhin Mihail petrov Sergey Makarov Pavel Belov Dmitry Zuev School of Physics and Engineering ITMO UniversityLomonosova 9Saint Petersburg 191002Russia Center for Nanotechnologies Alferov UniversityKhlopina 8/3Saint Petersburg 194021Russia Higher School of Engineering Physics Peter the Great Saint Petersburg Polytechnic UniversityPolitekhnicheskaya 29Saint Petersburg 195251Russia

Electric field is a powerful instrument in nanoscale engineering,providing wide functionalities for control in various optical and solid-state *** development of a single optically resonant nanostructure operating with a charge-induced electrical field is challenging,but it could be extremely useful for novel nanophotonic ***,we show a resonant metal-semiconductor nanostructure with a static electric field created at the interface between its components by charge carriers generated via femtosecond laser *** study this field experimentally,probing it by second-harmonic generation signal,which,in our system,is time-dependent and has a non-quadratic signal/excitation power *** developed numerical models reveal the influence of the optically induced static electric field on the second harmonic generation *** also show how metal work function and silicon surface defect density for different charge carrier concentrations affect the formation of this *** estimate the value of optically-generated static electric field in this nanoantenna to achieve≈10^(8)v/*** findings pave the way for the creation of nanoantenna-based optical memory,programmable logic and neuromorphic devices.

关键词： antenna optical field

Zeolite Synthesis under Insertion of Silica Rich Filtration Residues from Industrial Wastewater Reconditioning

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Advances in Chemical Engineering and Science 2014年第2期4卷 120-134页

作者： Andrea Hartmann v.petrov J.-C.Buhl K.Rübner M.Lindemann C.Prinz A.Zimathies Institut für Mineralogie Universitat HannoverHannoverGermany Fachgruppe vII.1 Baustoffe Bundesanstalt für Materialforschung und-prüfung(BAM)BerlinGermany Fachbereich 1.3 Strukturanalytik Richard-Willstätter Bundesanstalt für Materialforschung und-prüfung(BAM)BerlinGermany

Zeolite synthesis was studied using two silica rich filtration residues (FR 1 and FR 2) as Si-source and sodium aluminate in a direct synthesis at 60°C at strong alkaline conditions (8 M - 16 M NaOH). In addition to these one-pot syntheses, a two-step process was investigated. Here, an alkaline digestion of FR at 60°C was followed by gel precipitation with sodium aluminate and gel crystallization under usual conditions of 80°C - 90°C. The results show that the substitution of chemical reagent sodium silicate by a waste material like FR as Si-source is possible but requires fine tuning of the reaction conditions as zeolite crystallization is a process under kinetic control. The solubility behaviour and impurities of the inserted filtration residues strongly influenced the course of reaction. Thus zeolites like hydrosodalite or intermediate zeolite between cancrinite and sodalite, or zeolite NaA or Z-21 in cocrystallization with hydrosodalite could be observed in the one pot syntheses already in a short time interval between 1 - 4 h depending on the alkalinity. The two step process yield to zeolites NaA and NaX in very good quality. The reaction process of FR in both reaction methods was characterized by chemical analyses, X-ray powder diffraction, Fourier transform infrared spectroscopy as well as scanning electron microscopy. Surface area and water content of selected products were further characterized by the BET-method and by thermogravimetry. Summing up the results, we can show that zeolite formation from filtration residues is possible by several reaction procedures as model cases for a re-use of industrial waste materials. Beside the importance for environmental protection, the reactions are of interest for zeolite chemistry as the re-use of FR is possible under economically conditions of low energy consumption at 60°C and short reaction periods.

关键词： Zeolites Superalkaline Conditions Filtration Residues Re-Use of Industrial Waste Reaction Kinetics Silica Residue

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巯基捕收剂浮选细粒的某些特性

矿冶 1998年第2期7卷 21-26页

作者： petrov I A Davydov G I Studencov v v Revazashili I B (Kazmekhanobr,Republic of Kazakhstan) 哈萨克斯坦国家工业生态科技生产联合体

阐明了浮选不同粒级硫化物巯基捕收剂作用的研究。结果表明，当浮选细粒硫化物时，由于黑药的结构特点（有两个非极性基），它比黄药优越。按矿粒在气泡上沿环固着的假说，探讨了使用黄药和黑药时存在不同的矿物－气泡集合体的作用机理... 详细信息

阐明了浮选不同粒级硫化物巯基捕收剂作用的研究。结果表明，当浮选细粒硫化物时，由于黑药的结构特点（有两个非极性基），它比黄药优越。按矿粒在气泡上沿环固着的假说，探讨了使用黄药和黑药时存在不同的矿物－气泡集合体的作用机理。研究结果可用于修正选厂的药剂制度。

关键词：捕收剂细粒浮选巯基捕收剂细矿粒

How to stabilize standard perovskite solar cells to withstand operating conditions under an ambient environment for more than 1000 hours using simple and universal encapsulation

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Journal of Energy Chemistry 2023年第3期78卷 246-252,I0008页

作者： Nikolai A.Belich Andrey A.petrov Pavel A.Ivlev Natalia N.Udalova Alla A.Pustovalova Eugene A.Goodilin Alexey B.Tarasov Laboratory of New Materials for Solar Energetics Faculty of Materials ScienceLomonosov Moscow State University119991 MoscowRussia Department of Chemistry Lomonosov Moscow State University119991 MoscowRussia

We introduce a simple and universal scalable encapsulation strategy for perovskite solar cells based on thermal vacuum evaporation of MgF2or MoO3-xcapping layer followed by sealing the device with glass and Uv-curable *** proposed encapsulation method is beneficial to most of the other known encapsulation approaches being fully harmless to perovskite and transporting layers and processible at room *** deposition of the capping layer promotes efficient removal of water,oxygen and organic solvent residuals from the device prior to sealing and could be easily performed using standard equipment for metal electrode *** proposed strategy is transferrable to any lab-scale perovskite solar cell prototypes regardless of their geometry and architecture and results in excellent stability of the devices in ambient air and long operating *** the 1000 hours stability test at ambient air(30%-60% RH),the cells preserved 92.9% of their initial efficiency on average under 1 Sun illumination at constant maximum power point tracking(MPPT,ISOS-L-1) and over 96% under sto rage in the dark(ISOS-D-1),thus evidencing for the high effectiveness of the proposed encapsulation approach.

关键词： Perovskite solar cells Halide perovskites Encapsulation High stability ISOS-L-1