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Kinetics and mechanism of the low-energy b-a phase transition of the second kind in 2,4-dinitroanisole

Defence Technology（防务技术） 2024年第10期40卷 210-224页

作者： Aleksandr V.Stankevich nikolay a.rasputin Anisa KhRudina Gennady L.Rusinov Vera I.Filyakova Valery N.Charushin y1.postovsky institute of organic synthesis ural branch of the russian academy of sciencesekaterinburg 620108russia russian federal nuclear center e zababakhin all-russia research institute of technical physics snezhinsk 456770russia kazan national research technological university kazan 420015russia

In this work,comprehensive studies of 2,4-dinitroanisole(2,4DNAN)were carried out using powder thermorentgenography of the internal *** time of the complete polymorphic transition in the solid phase b/a in 2,4DNAN under various combinations of conditions has been *** has been established that,regardless of the season of manufacture of the substance,when it is stored for 8e9 months,with a change in ambient temperature from minus 30℃ to plus 30℃,a complete polymorphic transition b/a *** stored in conditions below minus 5℃,polymorphic transition does not *** stored in conditions above plus 30℃ in a closed container,polymorphic transition occurs within 3 *** polymorphic transition is accompanied by a decrease in density by 1.3%e1.5%and an increase in melting temperature by 10-12℃,depending on the degree of purity of the starting *** activation energy of the molecular rearrangement was 68e70 kJ/mol(16.5±3 kcal/mol).The mechanism of polymorphic transition has been evaluated,which is presumably based on internal homodiffusion and energy transfer to the surface of the mass of powder particles and the *** average activation energy of the polymorphic transition process was 110±6.2 kJ/mol(26.2 kcal/mol).In an open container,reactions proceed by a homogeneous mechanism,and in a closed container by a heterogeneous mechanism involving the gas phase.

关键词： Energetic materials Melt-castable 2,4-Dinitroanisole Polymorphic transition Kinetics Mechanism Homodiffusion Sublimation

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Saffman–Taylor instability in eccentric cylinders at gaseous cavitation

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Friction 2024年第2期12卷 356-362页

作者： Anatoliy A.MONAKHOV nikolay BUKHARIN Institute of Mechanics Moscow State UniversityMoscow 119899Russia ThermoFluid Solutions Ltd. CalgaryAlberta T3G4E8Canada

A flow of silicon fluid in the gap between eccentric cylinders was studied *** condition of gaseous cavitation inception during the rotation of internal cylinder was *** was shown that at reduction of the gap between cylinders Saffman–Taylor instability appeared on surface of the internal cylinder and then gaseous cavitation was *** of one uniform gas formation appearance under this type of instability was demonstrated.

关键词： gaseous cavitation Saffman-Taylor instability eccentric cylinders friction lubrication theory

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Ion-conducting Membranes Based on Bacterial Cellulose Nanofibers Modified by Poly(sodium acrylate-co-2-acrylamido-2-methylpropanesulfonic acid)

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Chinese Journal of Polymer Science 2024年第3期42卷 333-343,I0007页

作者： Elizaveta V.Batishcheva nikolay N.Smirnov Natalya V.Bobrova Maria P.Sokolova Michael A.Smirnov Institute of Macromolecular Compounds Russian Academy of SciencesBolshoy pr.31Saint Petersburg 199004Russia

Green method for preparation of ion-conducting membranes(ICM) based on bacterial cellulose nanofibers(CNF) modified by a copolymer of sodium acrylate and 2-acrylamido-2-methylpropanesulfonic acid was elaborated. FTIR and NMR data confirmed grafting of polyacrylate onto cellulose surface. Formation of porous structure of the ICM was controlled by SEM and AFM. The maximal ionic conductivity of the membranes reaches 1.5 and 3.1 mS·cm^(-1)(60 ℃ and 98% relative humidity) when they are saturated with water or H_2SO_4(1 mol·L^(-1)) electrolyte,respectively. Prepared ICM was tested as a separator in a symmetrical supercapacitor with electrodes based on polyaniline hydrogel. The assembled cell demonstrate ability to operate at high current density up to 100 A·g^(-1) maintaining specific capacitance 165 F·g^(-1). Maximal specific capacitance of 289 F·g^(-1) was achieved at current density 1 A·g^(-1). Retaining of 90% of initial capacitance after 10000 of charge-discharge cycles proves high electrochemical stability of prepared ICM.

关键词： Bacterial cellulose Ion conductivity Porous membrane Supercapacitor

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How the adoption of industry 4.0 technologies is related to participation in global and domestic value chains: Evidence from Russia

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International Journal of Innovation Studies 2024年第2期8卷 93-108页

作者： Anna A.Fedyunina nikolay A.Gorodnyi Yuri V.Simachev Centre for Industrial Policy Studies National Research University Higher School of EconomicMoscow11Pokrovsky BoulevardZip Code:101000Russia

This study explores the relationships among Industry 4.0 technologies, their application areas,and the involvement of Russian manufacturing firms in global and domestic value chains. Weapply logit and multinomial logit regressions using an original survey dataset of approximately1700 Russian manufacturing firms. We make a novel contribution to the literature by uncoveringan asymmetry in adopting Industry 4.0 technologies among Russian industrial firms in domesticvalue chains (DVCs) and global value chains (GVCs). This asymmetry has the potential to impedeGVC localization and DVC internationalization. Based on our results, software automation solu-tions are the only ones demonstrating statistical significance for firms participating simulta-neously in GVCs, DVCs, and both GVCs and DVCs. Companies in DVCs demonstrate a broaderutilization of Industry 4.0 technologies across various application areas. We also identify evidenceof reshoring in DVCs, indicating that Industry 4.0 adoption encourages firms to establish enduringrelationships with domestic suppliers. Highlighting that differences in technology adoption areinfluenced by external factors, including adherence to international standards and regulatoryprinciples, we propose policy implications for developing countries. Recommendations encom-pass reducing entry barriers to DVCs, improving procurement transparency, and promotingcompetition in the digital solutions market to empower firms for seamless GVC integration.

关键词： Industry 4.0 Global value chains Domestic value chains Forward linkages Backward linkages

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Catalytic co-combustion of biomass and brown coal in a fluidized bed:Economic and environmental benefits

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Journal of Environmental Sciences 2024年第6期140卷 24-36页

作者： Yury V.Dubinin nikolay A.Yazykov Petr M.Yeletsky Roman B.Tabakaev Aleksandra I.Belyanovskaya Vadim A.Yakovlev Federal Research Center Boreskov Institute of Catalysis SB RAS Lavrentiev Ave.5Novosibirsk630090Russia University of Tyumen Volodarskogo str.6Tyumen625003Russia

The work is devoted to the study of combustion of brown coal,pine sawdust,and their mixtures in a fluidized bed of catalyst at 600-750℃.It is shown that an increase in the content of sawdust in a mixture with brown coal leads to an increase in the burnout degree of solid fuel from 94.4%to 99.9%,while the emission of greenhouse gases in the form of CO_(2)CO and NOxis reduced(CO_(2)from the biomass is not included in the balance).The high content of alkaline earth metal oxides(CaO and MgO)in the mineral part of brown coal,sawdust,and their mixtures eliminates the emission of sulfur oxides and the slagging of heat-exchange surfaces during the combustion in a fluidized bed of *** optimal temperature,when the highest burnout degree of the above fuels is achieved in the combustion is 750℃.It is also shown that the increase in temperature and the content of sawdust in the composition of the fuel mixtures has a positive effect on the economic and environmental process indicators.

关键词： Co-combustion Fluidized catalyst bed Biomass Coal Economic effect Environmental impact

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Self-healable and Robust Film Based on Electroactive Polymer Brush as Electrode for Flexible Supercapacitor

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Chinese Journal of Polymer Science 2024年第8期42卷 1049-1059页

作者： Maria P.Sokolova Vitaly K.Vorobiov nikolay N.Smirnov Ivan S.Kuryndin Natalya V.Bobrova Michael A.Smirnov Institute of Macromolecular Compounds Russian Academy of SciencesBolshoy pr.31Saint Petersburg 199004Russia

The aim of this study was to develop self-healable and robust elect roconductive film based on polyaniline copolymer for application as electrode in flexible *** this purpose,the electroconductive polymer brushes(EPB)was *** synthesis of EPB is based on graft polymerizations of acrylamide(AAm)on poly(vinyl alcohol)(PVA)with formation of PVA-PAAm polymer brush and subsequent graft copolymerization of aniline and p-phenylenediamine on PVA-PAAm resulting in formation of EPB with electroconducting copoly(aniline-co-pphenylenediamine)(PAPh DA).It was found that the ratio between PVA and PAAm at the first stage greatly influence the electrochemical performance of the *** films were prepared by casting of EPB solution with subsequent *** of electrical current distribution through the film with AFM reveal more uniform distribution of PAPhDA in EPB in comparison with reference PVA-PAPhDA and PAAm-PAPhDA *** was demonstrated that mechanical cha racteristics and electrical conductivity values of films restore at large extent after curring and self-healing under optimal relative humidity level(58%).The flexile supercapacitor cell with EPB film electrodes demon strate specific capacitance 602 mF·cm^(-2)at the current density of 1 mA·cm^(-2)and retention 94%of initial capacitance after 5000 charge/discharge cycles.

关键词： Polymer brush Polyaniline Flexible supercapacitor Self-healing Electroconducting film

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伯醇对镍基催化剂在转移氢化反应中的抑制作用研究

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Chinese Journal of Catalysis 2024年第3期58卷 168-179页

作者： nikolay Nesterov Alexey Philippov Vera Pakharukova Evgeny Gerasimov Stanislav Yakushkin Oleg Martyanov 博列斯科夫催化研究所俄罗斯新西伯利亚

本文研究了在转移加氢条件下,不同类型醇作为氢供体对镍基催化剂在苯并呋喃加氢反应中的活性影响.结果表明,使用异丙醇作为氢供体时,苯并呋喃的加氢过程为底物先发生脱芳构化,然后再进行脱氧反应.然而,当使用伯醇如甲醇、乙醇和正丙醇... 详细信息

本文研究了在转移加氢条件下,不同类型醇作为氢供体对镍基催化剂在苯并呋喃加氢反应中的活性影响.结果表明,使用异丙醇作为氢供体时,苯并呋喃的加氢过程为底物先发生脱芳构化,然后再进行脱氧反应.然而,当使用伯醇如甲醇、乙醇和正丙醇作为氢供体时,会导致镍基催化剂的不可逆失活.针对这一现象,进一步研究了伯醇使镍基金属催化剂失活的机理.结果表明,在250°C条件下,催化剂与伯醇的相互作用会导致形成非活性的碳化物Ni_(3)C,并且镍金属颗粒在氧化铝载体表面会发生烧结和偏析.

关键词：苯并呋喃转移加氢超临界共沉淀 Ni催化剂醇

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超表面:塑造光子学的未来

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Science Bulletin 2024年第11期69卷 1607-1611页

作者： nikolay L.Kazanskiy Svetlana N.Khonina Muhammad A.Butt Samara National Research University Samara 443086Russia

A metasurface, often abbreviated as MS, represents a thin, artificially crafted surface consisting of an assembly of subwavelength structures that interact with light in distinct manners. Typically,smaller than the wavelength of the light they engage with, these structures empower precise management of light properties such as polarization, phase, and amplitude.

关键词： precise abbreviated 光子学

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The biosynthetic pathway of the hallucinogen mescaline and its heterologous reconstruction

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Molecular Plant 2024年第7期17卷 1129-1150页

作者： Paula Berman Luis Alejandro de Haro Ana-Rita Cavaco Sayantan Panda Younghui Dong nikolay Kuzmich Gabriel Lichtenstein Yoav Peleg Hila Harat Adam Jozwiaki Jianghua Cai Uwe Heinig Sagit Meir Ilana Rogachev Asaph Aharoni Department of Plant and Environmental Sciences Weizmann Institute of ScienceRehovot 7610001Israel Life Sciences Core Facilities Weizmann Institute of ScienceRehovot 7610001Israel The Maurice and Vivienne Wohl Institute for Drug Discovery Weizmann Institute of ScienceRehovot 7610001Israel Present address:Department of Cell and Metabolic Biology Leibniz Institute of Plant BiochemistryWeinberg 306120 Halle(Saale)Germany Department of Molecular&Cellular Pharmacology University of Miami Miler School of MedicineMiamiFL 33136USA Department of Botany and Plant Sciences University of California RiversideRiversideCA 92521USA Laboratory of Plant Hormones and Development Regulation of Chongqing School of Life SciencesChongqing UniversityChongqing 401331China

Mescaline,among the earliest identified natural hallucinogens,holds great potential in psychotherapy ***,despite the existence of a postulated biosynthetic pathway for more than half a century,the specific enzymes involved in this process are yet to be *** this study,we investigated the cactus Lophophora williamsii(Peyote),the largest known natural producer of the phenethylamine *** employed a multi-faceted approach,combining de novo whole-genome and transcriptome sequencing with comprehensive chemical profiling,enzymatic assays,molecular modeling,and pathway engineering for pathway *** identified four groups of enzymes responsible for the six catalytic steps in the mescaline biosynthetic pathway,and an N-methyltransferase enzyme that N-methylates all phenethylamine intermediates,likely modulating mescaline levels in ***,we reconstructed the mescaline biosynthetic pathway in both Nicotiana benthamiana plants and yeast cells,providing novel insights into several challenges hindering complete heterologous mescaline *** together,our study opens up avenues for exploration of sustainable production approaches and responsible utilization of mescaline,safeguarding this valuable natural resource for future generations.

关键词： mescaline Lophophora williamsi Peyote biosynthetic pathway de novo genome sequencing mo-lecular modeling

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集成氮化硅微腔中呼吸子频率的注入锁定研究（特邀）

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激光与光电子学进展 2024年第19期 91-97页

作者：张一斐杨华山 nikolay Pavlov 何吉骏潘时龙南京航空航天大学微波光子技术国家级重点实验室 Enlightra 空天集成电路与微系统工信部重点实验室

耗散克尔孤子是基于光学微腔产生的宽带低噪声光学频率梳，具有稳定的时域脉冲，在光谱分析、通信和精密测量等多个领域显示出极大的应用潜力。呼吸子是耗散克尔孤子的一种特殊类型，其脉冲持续时间和峰值强度会呈现周期性的振荡。研究... 详细信息

耗散克尔孤子是基于光学微腔产生的宽带低噪声光学频率梳，具有稳定的时域脉冲，在光谱分析、通信和精密测量等多个领域显示出极大的应用潜力。呼吸子是耗散克尔孤子的一种特殊类型，其脉冲持续时间和峰值强度会呈现周期性的振荡。研究了集成氮化硅微腔中的呼吸耗散克尔孤子，在实验过程中观察到其呼吸频率约为290 MHz且表现出约为MHz量级的不稳定性。这是其在未来应用中的主要障碍。通过在呼吸频率的波动范围内对泵浦激光器施加适当的调制信号，可以将呼吸频率注入锁定到该调制信号的频率，注入锁定的范围约为10 MHz，锁定之后线宽由11 MHz压窄为35 kHz。此外，在实验过程中还观察到了另一种由于模间相互作用而导致的呼吸子，其呼吸频率约为295 MHz。并同样对其进行了注入锁定实验，实现了呼吸频率的稳定。该研究工作为微腔中呼吸子的实际应用提供了新的思路，预期可以作为多波长源应用在多通道的调幅连续波激光雷达中。

关键词：集成氮化硅微腔光学频率梳呼吸子注入锁定

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