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Temperature dependences of electric properties of tetramethylammonium mono-and pentaiodide

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Journal of Advanced Dielectrics 2019年第6期9卷 81-86页

作者： Irina D.Yushina Fedor V.Podgornov maxim Gavrilyak Victor Boronin Ekaterina V.Bartashevich South Ural State University 76 Lenin Avenue Chelyabinsk 454080Russian Federation Institute of Electrophysics Ural Branch of Russian Academy of Sciences 106 Amundsen str. Ekaterinburg 620216Russian Federation

The dielectric properties of tetramethylammonium monoiodide and pentaiodide were investigated in broad temperature range(-150℃till+50℃).It was demonstrated that the structural organization of the polyiodide chain containing I...I charge-assisted halogen bonds influenced the parameters and the mechanism of electric conductivity of considered *** impedance spectroscopic measurements revealed that the direct current electric conductivity of pentaiodide salt is around four orders of magnitude higher than that of corresponding ***,pentaiodide demonstrates the hopping mechanism of conductivity.

关键词： Impedance spectroscopy electric conductivity tetramethylammonium salts polyiodides halogen bonding

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烯烃聚合钯催化剂研究进展

化学通报 2012年第8期75卷 681-690页

作者：张呈平聂万丽 Borzov maxim V 西北大学化学与材料科学学院合成与天然功能分子化学教育部重点实验室西安710069

综述了烯烃聚合钯催化剂的研究进展,烯烃聚合钯催化剂的配体类型有膦配体、氮配体、碳配体、氧配体、氮-氧配体、膦-氧配体、氮-膦配体等。与齐格勒-纳塔催化剂和茂金属催化剂相比,烯烃聚合钯催化剂具有高催化活性、单活性中心和良好的... 详细信息

综述了烯烃聚合钯催化剂的研究进展,烯烃聚合钯催化剂的配体类型有膦配体、氮配体、碳配体、氧配体、氮-氧配体、膦-氧配体、氮-膦配体等。与齐格勒-纳塔催化剂和茂金属催化剂相比,烯烃聚合钯催化剂具有高催化活性、单活性中心和良好的分子剪裁性等优点,可在分子层次上实现烯烃聚合的分子设计与组装;与铁、钴、镍等后过渡金属催化剂相比,烯烃聚合钯催化剂具有反应条件较温和、催化活性和立体选择性较高的优势。

关键词：钯催化剂后过渡金属催化剂烯烃聚合反应

Current Networks of Long Proxies for Building Reconstruction Models of the Atlantic Multidecadal Oscillation

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Atmospheric and Climate Sciences 2016年第3期6卷 367-374页

作者： Markus Lindholm Risto Jalkanen maxim G. Ogurtsov Luke Rovaniemi Research Unit Rovaniemi Finland A.F. Ioffe Physico-Technical Institute St. Petersburg Russia

Currently available proxies were studied as networks for building reconstruction models of the Atlantic Multidecadal Oscillation (AMO). Only proxies that would double the current record length (backwards in time from AD 1564) were included. We present two proxy networks and corresponding reconstruction (transfer) models, one for tree-growth based proxies only and another for multiproxies. Both of them show a useful match in timing as well as amplitude with the AMO. These model structures demonstrated reasonable model performance (overall r2 = 0.45 - 0.36). The time stability of proxy-AMO relationships was also validated. The new models produced acceptable results in cross-calibration-verification (reduction of error and coefficient of efficiency statistics in 1856-1921 and 1922-1990 vary between 0.41 and 0.21). The spatial distribution of these data series indicate that proxies respond to an AMO-like climatic oscillation over much of the Northern Hemisphere.

关键词： Proxies Atlantic Multidecadal Oscillation Tree Growth Climate Change Transfer Models

Harnessing self-heating effect for ultralow-crosstalk electro-optic Mach–Zehnder switches

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Photonics Research 2023年第10期11卷 1757-1769页

作者： PENG BAO QIXIANG CHENG JINLONG WEI GIUSEPPE TALLI maxim KUSCHNEROV RICHARD V.PENTY Centre for Photonic Systems Electrical Engineering DivisionDepartment of EngineeringUniversity of CambridgeCambridge CB30FAUK Huawei Technologies Duesseldolf GmbH European Research Center80992 MunichGemany Current address:Peng Cheng Laboratory Shenzhen 518000China

This paper presents a novel approach to counterbalance free-carrier-absorption(FCA) in electro-optic(E-O)Mach–Zehnder interferometer(MZI) cells by harnessing the self-heating effect. We show insights on crosstalk limitations in MZIs with direct carrier-injection and provide a detailed design methodology on a differential phase shifter pair. Leveraging both free-carrier dispersion(FCD) and self-heating effects, our design enables arbitrary phase tuning with balanced FCA loss in the pair of arms, eliminating the need for additional phase corrections and creating ultralow crosstalk MZI elements. This neat design disengages from the commonly used nested structure, thus providing an opportunity of embedding tunable couplers for correcting imperfect splitting ratios given that only two are needed. We show that with the use of tunable directional couplers, a standard±10 nm process variation is tolerated, while achieving a crosstalk ratio below-40 dB. By direct carrier injection in both arms, the proposed device operates at nanosecond scales and can bring about a breakthrough in the scalability of E-O switch fabrics, as well as other silicon integrated circuits that have stringent requirements for crosstalk leakage.

关键词： crosstalk interferometer breakthrough

Case Series of Methylene Blue Injections for the Treatment of Zygapophysial and Sacroiliac Joint Pain: Results of 5 Cases

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Open Journal of Anesthesiology 2013年第6期3卷 301-303页

作者： Jay Parekh maxim Eckmann Somayaji Ramamurthy University of Texas Health Science Center at San Antonio San Antonio USA.

Introduction: Shealy is credited with the use of fluoroscopy guided radiofrequency ablation (RFA) for denervation of the lumbar zygapophysial (L-Z) joint in the mid-1970’s. Peng and colleagues described the use of methylene blue (MB) injection for discogenic pain;MB may work through direct neurotoxicity or inhibition of nitric oxide synthesis. We present a retrospective case series of five patients with L-Z or SI joint pain where MB used as an alternative to RFA. Materials and Methods: This is a retrospective case series of five patients who received MB for the chemical neurolysis of either medial or/and lateral branch’s for zygapophysial or SI joint pain. All of the MB blocks were done under fluoroscopic guidance and performed in the same manner as diagnostic medial and lateral branch blocks but with care to consider the medication as neurotoxic in relation to spinal nerves. On average 1cc of 0.05% final concentration MB was injected per nerve or sacral foraminal level. Results: Four of the five patients had significant lasting pain relief. Discussion: Chemical neurolysis has potential to achieve technical success in these refractory cases of spine pain possibly due to spread over a broader area;for this same reason the procedure should be performed carefully under fluoroscopic guidance.

关键词： Radio Frequency Ablation Facet Zygapophysial Sacroiliac Methylene Blue Pain Interventional

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硅烷阳离子活性研究进展

化学通报 2013年第9期76卷 786-790页

作者：聂万丽刘敏霞 maxim V Borzov 乐山师范学院化学学院生物有机与表面科学重点实验室乐山614000 西北大学化学与材料科学学院合成与天然功能分子化学教育部重点实验室西安710069

硅烷阳离子具有独特的三价特征及高的亲电性和路易斯酸性,近年来其在有机合成中的应用受到广泛关注。本文主要从结构特征和反应活性两方面对硅烷阳离子进行了总结。对其稳定的结构类型、在CO2的活化及转化中的应用、催化C—F键的活化(... 详细信息

硅烷阳离子具有独特的三价特征及高的亲电性和路易斯酸性,近年来其在有机合成中的应用受到广泛关注。本文主要从结构特征和反应活性两方面对硅烷阳离子进行了总结。对其稳定的结构类型、在CO2的活化及转化中的应用、催化C—F键的活化(氢化去氟反应)以及作为一种新型的路易斯酸在催化Diels-Alder反应中的优越反应性能四个方面进行了介绍。

关键词：三价硅阳离子 CO2的活化氢化去氟反应路易斯酸Diels—Alder反应

Deep Bayesian local crystallography

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npj Computational Materials 2021年第1期7卷 1649-1660页

作者： Sergei V.Kalinin Mark P.Oxley Mani Valleti Junjie Zhang Raphael P.Hermann Hong Zheng Wenrui Zhang Gyula Eres Rama K.Vasudevan maxim Ziatdinov Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831USA Bredesen Center for Interdisciplinary Research The University of TennesseeKnoxvilleTN 37996USA Materials Science and Technology Division Oak Ridge National LaboratoryOak RidgeTN 37831USA Materials Science Division Argonne National LaboratoryArgonneIL 60439USA Computational Sciences and Engineering Division Oak Ridge National LaboratoryOak RidgeTN 37831USA Present address:State Key Laboratory of Crystal Materials&Institute of Crystal Materials Shandong UniversityJinanShandong 250100China

The advent of high-resolution electron and scanning probe microscopy imaging has opened the floodgates for acquiring atomically resolved images of bulk materials,2D materials,and *** plethora of data contains an immense volume of information on materials structures,structural distortions,and physical *** this knowledge regarding local physical phenomena necessitates the development of the mathematical frameworks for extraction of relevant ***,the analysis of atomically resolved images is often based on the adaptation of concepts from macroscopic physics,notably translational and point group symmetries and symmetry lowering ***,we explore the bottom-up definition of structural units and symmetry in atomically resolved data using a Bayesian *** demonstrate the need for a Bayesian definition of symmetry using a simple toy model and demonstrate how this definition can be extended to the experimental data using deep learning networks in a Bayesian setting,namely rotationally invariant variational autoencoders.

关键词： symmetry local resolved

Perylene Diimide Incorporated Polyurethane Polymer as Potential Colour Filter Material with Non-fluorescent Property

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Chinese Journal of Chemistry 2023年第11期41卷 1348-1354页

作者： Xin-Yi Zhang Kai-Li Tian Jie Liu Wittaya Ngeontae Ai-Juan Zhao maxim V. Bermeshev Shi-Qing Wong Kaspars Traskovskis Zhijian Chen Xiang-Kui Ren School of Chemical Engineering and Technology State Key Laboratory of Chemical EngineeringTianjin UniversityTianjin300350 China Department of Chemistry Faculty of ScienceKhon Kaen UniversityKhon Kaen40002 Thailand A.V.Topchiev Institute of Petrochemical Synthesis of Russian Academy of Sciences Moscow119991 Russia Faculty of Materials Science and Applied Chemistry Riga Technical UniversityRigaLV-1048 Latvia Zhejiang Institute of Tianjin University NingboZhejiang315201 China

A novel polyurethane polymer containing perylene diimide(PDI)unit and aniline segment,denoted as PU-PDI,was designed and *** tensile property and photophysical characteristic were investigated using various experimental and theoretical *** is found that the elongation of PU-PDIs can reach more than 1000%,indicating good tensile ***,based on the photoinduced electron transfer mechanism,the aniline segments in polyurethane can quench the auto-fluorescence of PDI unit to a negligible value,which overcomes the intractable fluorescence drawbacks of conventional colour *** non-emissive characteristic,in combination with the good thermal stability and tensile property of PU-PDI,provides a feasible design strategy to fabricate optical filters with high display quality.

关键词： Perylene dimide Polyurethane Photoinduced electron transfer Fluorescence quenching Colour filter

Search for Signatures of New Heavy Top Quark of the Fourth Generation at the Hadron Colliders

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Open Journal of Microphysics 2014年第4期4卷 35-45页

The Fourth Generation and Vector Like Quark (VLQ) models are extensions of the Standard Model of particles physics. These models predict the existence of new heavy quarks like heavy top quark t' with electric charge 2/3 and heavy bottom quark b' with electric charge -1/3. The t' and b' will act the fourth generation quarks. In current work we present a search for a pair production of a fourth generation quark, t' quark and its antiparticle, followed by their decays to Z, W bosons followed by decays to trilepton e-e-μ+ plus jets and missing transverse energy in the final state according to the process . We use Monte Carlo simulation techniques Pythia8, MadGraph5 and CalcHEP to simulate this process at both the Large Hadron Collider at CERN (proton-proton collisions) and the Fermilab Tevatron Collider (proton-antiproton collisions). We assume that the t' quark is a narrow state that always decay to a W and Z bosons plus jets. We select 2 electrons + jets+ missing energy final states with one isolated μ with high transverse momentum. The three charged leptons plus missing energy in the final state offer the best discovery potential at the hadron colliders for new heavy top quark mass of 500 GeV. We study the possible signals at both the LHC and the Tevatron of new quarks t' coupled to the third generation quarks in the context of fourth generation and vector like quark models under the assumption of a branching ratios BR(t'→Wb)=50%?and BR(t'→Zt)=50%. Heavy quark pair production gives interesting signals in final states with three charged leptons plus missing energy. Finally, from our analysis the new heavy fourth generation quark t' can be discovered at both the Tevatron and the LHC with mass 500 GeV.

关键词： LHC Tevatron Fourth Generation Model Heavy Top Monte Carlo Simulation