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Radiation of a TM mode from an open end of a three-layer dielectric capillary

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Chinese Physics B 2024年第7期33卷 311-318页

作者： Sergey NGalyamin Alexandr MAltmark st.petersburg state University 7/9Universitetskayanab.St.Petersburg 199034Russia st.petersburg Electrotechnical University“LETI” 5ProfessoraPopovaSt.Petersburg 197022Russia

Modern trends in beam-driven radiation sources include the interaction of Cherenkov wakefields in open-ended circular waveguides with complicated dielectric linings, with a three-layer dielectric capillary recently proposed to reduce radiation divergence being a representative example [Opt. Lett. 45 5416(2020)]. We present a rigorous approach that allows for an analytical description of the electromagnetic processes that occur when the structure is excited by a single waveguide TM mode. In other words, the corresponding canonical waveguide diffraction problem is solved in a rigorous formulation. This is a continuation of our previous papers which considered simpler cases with a homogeneous or two-layer dielectric filling. Here we use the same analytical approach based on the Wiener–Hopf–Fock technique and deal with the more complicated case of a three-layer dielectric lining. Using the obtained rigorous solution, we discuss the possibility of manipulating the far-field radiation pattern using a third layer made of a low permittivity material.

关键词： diffraction radiation open-ended waveguide Wiener–Hopf technique Cherenkov radiation

Microwave diagnostics of pulsed atmospheric discharge with electrolytic electrode and long-lived luminous formation in its afterglow

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High Voltage 2024年第1期9卷 127-136页

作者： Shixin Zhao Xingbao Lyu Aleksandr Astafiev Chengxun Yuan Lin Miao Jingfeng Yao Ying Wang Anatoly Kudryavtsev Aleksandr Chirtsov Gennadii Shabanov Zhongxiang Zhou School of Physics Harbin Institute of TechnologyHarbinChina Physics Department Saint Petersburg Electrotechnical University“LETI”St.PetersburgRussia Heilongjiang Provincial Key Laboratory of Plasma Physics and Application Technology HarbinChina Physics Department St.Petersburg State UniversitySt.PetersburgRussia Konstantinov petersburg Nuclear Physics Institute National Research Centre“Kurchatov Institute”GatchinaRussia

The Gatchina discharge phenomenon holds significant promise as a laboratory model for simulating ball ***,crucial aspects concerning the plasma components of the resulting afterglow remain ***,the measurement of the electron density,a critical parameter,has not been fully achieved thus *** this study,microwave diagnostics and video recording were employed during a pulsed Gatchina discharge,along with synchronous measurement of discharge current and *** antennas were positioned at different heights to enable separate diagnosis of the discharge and the ensuing long-lived *** findings revealed that during the active phase of the Gatchina discharge,the plasma density was substantial enough to cause reflection of an electromagnetic wave with a frequency of 20 GHz from this highly conductive *** the afterglow,the signal experienced only a moderate weakening of 10–20 percent,facilitating the determination of the time dependence of average electron density during the afterglow's passage between the two *** measurements verified the unusually slow plasma decay in the afterglow of the Gatchina discharge,suggesting the potential significance of chemi-ionisation processes involving long-lived(metastable)particles.

关键词： holds luminous electrolytic

Polyelectrolyte Complexes between Hyperbranched and Linear Polysaccharides: Fucoidan/Chitosan

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Chinese Journal of Polymer Science 2024年第4期42卷 468-479页

作者： Ekaterina R.Gasilova Daria N.Poshina Aleksandra O.Sitnikova Natalia N.Saprykina Yury A.Skorik Institute of Macromolecular Compounds of the Russian Academy of Sciences Bolshoi VO 31St.Petersburg199004Russian Federation

Polyelectrolyte complexes(PECs)of hyperbranched(HB)and linear polysaccharides are promising as more effective encapsulation agents compared to PECs formed by linear *** investigated the PECs between the HB anionic polysaccharide fucoidan(FUC)and the cationic linear polysaccharide chitosan(CS).The FUC had a molecular weight(MW)of 30×*** PECs were prepared in three solvents(water,0.01 and 0.1 mol/L acetic acid)with CS of MW of 15,110 and 170 kDa,and deacetylation degrees(DDA)of 70%and 97%.The structures of the PECs and the initial FUC were investigated by multi-angle static and dynamic light *** the FUC contained 18 wt%of—OSO3 groups and 5 wt%of uronic acid units,it was a“strong-weak”copolyanion,so the HB macromolecules of the FUC formed nanogel particles in 0.1 mol/L AcOH and open branched structures in water,as confirmed by the Kratky *** mixing the solutions of original components,the PEC structures underwent an equilibration period,the duration of which increased with the MW of *** the charge stoichiometry was approached,the PECs shrank;the fractal dimension approached unity,indicating the side-by-side packing of adjacent FUC branches with the help of *** aggregation in the vicinity of the charge compensation was hardly observed,as it occurred in a very narrow *** PEC content at theζ-potential inversion depended on solvents’pH and the DDA of *** the extreme case of core-shell PECs in 0.1 mol/L AcOH,obtained by mixing FUC nanogels with the solutions of high MW CS of 97%DDA,the protruding tails of CS formed a positively charged shell in the whole range of FUC content(10 wt%

关键词： Polyelectrolyte complexes Chitosan Hyperbranched fucoidan Light scattering

Comparison of Perovskite Systems Based on AFeO_(3)(A=Ce,La,Y)in CO_(2) Hydrogenation to CO

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Transactions of Tianjin University 2024年第4期30卷 337-358页

作者： Anna N.Matveyeva Shamil O.Omarov Laboratory of Materials and Processes for Hydrogen Energy Ioff e Institute194021 St.PetersburgRussia

CO_(2) is the most cost-eff ective and abundant carbon resource,while the reverse water-gas reaction(rWGS)is one of the most eff ective methods of CO_(2) *** work presents a comparative study of rWGS activity for perovskite systems based on AFeO_(3)(where A=Ce,La,Y).These systems were synthesized by solution combustion synthesis(SCS)with diff erent ratios of fuel(glycine)and oxidizer(φ),diff erent amounts of NH 4 NO_(3),and the addition of alumina or silica as *** techniques,including X-ray diff raction analysis,thermogravimetric analysis,Fourier transform infrared spectroscopy(FTIR),scanning electron microscopy,energy-dispersive X-ray spectroscopy,N 2-physisorption,H_(2) temper-ature-programmed reduction,temperature-programmed desorption of H_(2) and CO_(2),Raman spectroscopy,and in situ FTIR,were used to relate the physicochemical properties with the catalytic performance of the obtained *** specifi c perovskite-containing system(either bulk or supported)has its own optimalφand NH_(4) NO_(3) amount to achieve the highest yield and dispersion of the perovskite *** all synthesized systems,bulk SCS-derived La-Fe-O systems showed the highest resistance to reducing environments and the easiest hydrogen desorption,outperforming La-Fe-O produced by solgel combustion(SGC).CO_(2) conversion into CO at 600°C for bulk ferrite systems,depending on the A-cation type and preparation method,follows the order La(SGC)stem based on La-Fe-O,obtained by the SCS method.γ-Al_(2)O_(3) improves the dispersion of CeFeO_(3) and LaFeO_(3) phases,the specifi c surface area,and the quant

关键词： Perovskites LaFeO_(3) CeFeO_(3) YFeO_(3) Solution combustion synthesis CO_(2) hydrogenation Reverse water–gas reaction(rWGS)

Systemic juvenile idiopathic arthritis–associated lung disease: A retrospective cohort study

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World Journal of Clinical Pediatrics 2024年第1期13卷 73-83页

作者： Konstantin E Belozerov Natalia M Solomatina Eugenia A Isupova Alla A Kuznetsova Mikhail M Kostik Department of Pediatric Saint-Petersburg State Pediatric Medical UniversitySaint-Petersburg 194100Russia st.petersburg state Budgetary Institution of Health Care Children's City Polyclinic No.29 of the Kalininsky District of St.PetersburgSt.Petersburg 195274Russia Research Laboratory of Autoimmune and Autoinflammatory Diseases World-Class Research Centre for Personalized MedicineAlmazov National Medical Research CentreSt.Petersburg 197341Russia

BACKGROUND Lung damage in systemic juvenile arthritis(sJIA)is one of the contemporary topics in pediatric *** previous studies showed the severe course and fatal outcomes in some *** information about interstitial lung disease(ILD)in the sJIA is scarce and limited to a total of 100 *** To describe the features of sJIA patients with ILD in *** In the present retrospective cohort study,information about 5 patients less than 18-years-old with sJIA and ILD were *** diagnosis of sJIA was made according to the current 2004 and new provisional International League of Associations for Rheumatology criteria *** was diagnosed with chest computed tomography with the exclusion of other possible reasons for concurrent lung *** activation syndrome(MAS)was diagnosed with HLH-2004 and 2016 EULAR/ACR/PRINTO Classification Criteria and hScores were calculated during the lung *** The onset age of sJIA ranged from 1 year to 10 *** time interval before ILD ranged from 1 mo to 3 *** disease course was characterized by the prevalence of the systemic features above articular involvement,intensive rash(100%),persistent and very active MAS(hScore range:194-220)with transaminitis(100%),and respiratory symptoms(100%).Only 3 patients(60%)developed a clubbing *** patients(100%)had pleural effusion and 4 patients(80%)had pericardial effusion at the disease *** patients(40%)developed pulmonary arterial ***-related reactions to tocilizumab were observed in 3(60%)of the *** patient with trisomy 21 had a fatal disease *** of the remaining patients had sJIA remission and 2 patients had *** disease improved in 3 patients(75%),but 1 of them had initial deterioration of lung *** patient who has not achieved the sJIA remission had the progressed course of *** cases of hyper-eosinophilia were *** patients(80%)received

关键词： Systemic juvenile arthritis Interstitial lung disease Canakinumab Tocilizumab Interleukin-6 Interleukin-1

Management of persistent urine leak after partial nephrectomy:A case series

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Current Urology 2024年第2期18卷 155-158页

作者： Bakhman Guliev Boris Komyakov Maksim Shevnin Murad Agagyulov Ali Talyshinskii Department of Urology North-Western State Medical UniversitySt.PetersburgRussia Center of Urology City Mariinsky HospitalSt.PetersburgRussia

Urinary leak is one of the most significant complications after partial *** case of persistent urine leaks,placement of a ureteral stent is effective but not always *** study included 5 patients with persistent urinary leak after partial *** patients underwent flexible ureteroscopy wherein we identified the damaged ***,we performed percutaneous puncture targeting the distal end of the endoscope at this calyx and installed a nephrostomy ***,the endoscope was removed,and the ureter was drained with a *** stenting ensures elimination of urinary leak in most patients after partial *** patients with persistent urinary leak,retrograde endoscopic percutaneous drainage of the pelvicalyceal system is the method of choice because it allows for rapid and effective treatment of urinary fistulas.

关键词： Complication Endoscopic treatment Flexible ureteroscopy Kidney cancer Urinary fistula

Cross-method Analysis of Corotation Radii Data Set for Spiral Galaxies

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Research in Astronomy and Astrophysics 2024年第7期24卷 95-110页

作者： V.S.Kostiuk A.A.Marchuk A.S.Gusev sternberg Astronomical Institute Lomonosov Moscow State UniversityUniversitetsky pr.13119234 MoscowRussia Central(Pulkovo)Astronomical Observatory Russian Academy of SciencesPulkovskoye chaussee 65/1196140 St.PetersburgRussia Saint petersburg state University Universitetsky pr.28198504 St.PetersburgRussia

A corotation radius is a key characteristic of disk galaxies that is essential to determine the angular speed of the spiral structureΩ_p,and therefore understand its *** the literature,there are plenty of methods to estimate this value,but do these measurements have any consistency?In this work,we collected a data set of corotation radius measurements for 547 galaxies,300 of which had at least two *** initial analysis reveals that most objects have rather inconsistent corotation radius ***,a significant fraction of galactic disks is distinguished by a large error coverage and almost uniform distribution of *** findings do not have any relation to spiral type,Hubble classification,or presence of a *** other reasons,obtained results could be explained by the transient nature of spirals in a considerable part of *** have made our collected data sample publicly available,and have demonstrated on one example how it could be useful for future research by investigating a winding time value for a sample of galaxies with possible multiple spiral arm patterns.

关键词： galaxies fundamental parameters-galaxies kinematics and dynamics-galaxies structure

What Mice Can Teach Us about How to stop Drug-Resistant Tuberculosis:Correct Chemotherapy Regimen and Patient Compliance are the Key

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Biomedical and Environmental Sciences 2024年第9期37卷 1086-1090页

作者： Igor Mokrousov Tatiana Vinogradova Marine Dogonadze Maria Vitovskaya Natalia Zabolotnykh Sergei Chekrygin Anna Vyazovaya Laboratory of Molecular Epidemiology and Evolutionary Genetics St.Petersburg Pasteur InstituteSt.Petersburg197101Russia Henan International Joint Laboratory of Children’s Infectious Diseases Children’s Hospital Affiliated to Zhengzhou UniversityHenan Children’s Hospital Zhengzhou Children’s HospitalZhengzhou 450012HenanChina st.petersburg Research Institute of Phthisiopulmonology St.PetersburgRussia Resource Center Bio-bank Center Research Park of St.Petersburg State UniversitySt.PetersburgRussia

Despite well-known limitations,mice remain useful as model animals to study tuberculosis(TB)pathogenesis,the basic immune response,the extent of lung pathology as well as efficacy of new drugs against Mycobacterium tuberculosis[1,2].There are four routes of tuberculosis infection in mice:aerosol generation and exposition,intravenous injection,intranasal administration,and subcutaneous administration[3].

关键词： tuberculosis drugs injection

丙酮盐酸混合液提取土壤腐殖质组分的光谱学特征

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光谱学与光谱分析 2024年第2期44卷 474-479页

作者：宋鸽孔祥仕黑龙江大学中俄学院黑龙江哈尔滨150080 Institute of Earth Sciences St.Petersburg State UniversitySt.Petersburg 199034Russia 吉首大学旅游学院湖南吉首416000

采用丙酮盐酸混合液提取土壤胡敏酸(HA)和胡敏素(HU)组分,利用元素分析、紫外-可见漫反射光谱和红外光谱进行结构表征。元素分析表明,HA中C、H、N和S含量均高于HU,O含量低于HU。原子比分析表明HA的缩合度相对较高,分子结构相对复杂,HU... 详细信息

采用丙酮盐酸混合液提取土壤胡敏酸(HA)和胡敏素(HU)组分,利用元素分析、紫外-可见漫反射光谱和红外光谱进行结构表征。元素分析表明,HA中C、H、N和S含量均高于HU,O含量低于HU。原子比分析表明HA的缩合度相对较高,分子结构相对复杂,HU的缩合度相对较低,分子结构相对简单。紫外-可见漫反射光谱分析表明,由于腐殖质(HS)的组成复杂,多种官能团互相干扰,HA和HU紫外-可见漫反射光谱无明显特征峰,吸光度值随着波长的增加呈下降趋势,且HA包含的吸光有机成分较多,化学组成较复杂。HA和HU紫外特征参数SUV254和E4/E6比较分析表明,与HU相比,HA芳香性较大,腐殖化程度较高。红外光谱分析表明,HA和HU具有相似的红外光谱,各研究对象特征吸收峰的吸收强度不同,其中开垦黑土20~40 cm和未开垦灰土18~37 cm土层HA的振动幅度较大,说明其包含的酚类化合物、含羟基化合物、脂肪族化合物和羧酸,以及含羰基的醛、酮、醚等化合物的含量较多。开垦黑土10~20 cm土层和未开垦灰土18~37 cm土层HU在各特征吸收峰振动幅度较大,说明其包含的酚类化合物、羧酸、脂肪烃和糖类化合物含量较多。红外光谱各吸收峰强度比较分析表明,开垦后黑土HA和HU酚类化合物、羟基官能团和脂肪族化合物等含量增加,而开垦后灰土HA和HU酚类化合物、羧酸和脂肪族化合物含量下降,表明开垦对黑土土壤有机质影响相对较小,并且在一定程度上增加了土壤有机质含量,而促进了灰土土壤有机质的分解。综上所述,丙酮盐酸混合液提取法为HS生物化学和生理活性的研究提供了新的技术手段,为合理利用土壤资源提供理论依据。

关键词：胡敏酸胡敏素元素分析紫外-可见漫反射光谱近红外光谱