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Maximizing catalytic efficiency with bio-inspired hierarchical porous zeolites

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National Science Review 2023年第7期10卷 74-76页

作者： svetlana Mintova Laboratory of Catalysis and Spectrochemistry (LCS) ENSICAEN CNRS Normandy University

Hierarchical porous materials are characterized by their elegant interconnectivity and regularity across multiple length scales,which enables rapid mass transfer,exchange,and high catalytic performance [1].Thhese advanced materials differ from single-length-scale porous materials like microporous zeolites [2],mesoporous MCM-41 [3],SBA-15 [4]and MOF [5],and they are considered to be the second generation of porous materials [1,6].These materials haveattracted significant academic and industrial attention [7].

关键词： SILICA

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纳米材料在植物激素中的应用及研究进展

仲恺农业工程学院学报 2024年第3期37卷 66-77页

作者：林依彤尹国强周红军 BABITSKAYA svetlana 周新华左继浩仲恺农业工程学院化学化工学院广东广州510225 仲恺农业工程学院广东省普通高校农业绿色精细化学品重点实验室广东广州510225 白俄罗斯国家科学院生物有机化学研究所明斯克州明斯克220141

对纳米技术在植物激素中的应用,包括单一纳米材料对内源植物激素的影响、纳米粒子-外源植物激素复合材料以及负载植物激素的纳米材料在植物中的应用进行了综述,对未来纳米技术在植物激素施用过程中的发展进行了展望.

关键词：纳米技术植物激素缓控释体系

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绵萆薢的化学成分研究

山东科学 2024年

作者：刘伟于金倩董红敬 BOTIROV Erkin Khozhiakbarovich GUSAKOVA svetlana Dmitrievna 王晓齐鲁工业大学(山东省科学院)山东省分析测试中心天然产物分离提取共性技术创新与应用山东省工程研究中心齐鲁工业大学(山东省科学院)药学院乌兹别克斯坦国家科学院植物化学研究所

利用大孔树脂、MCI柱色谱、凝胶柱色谱和制备液相等对绵萆薢化学成分进行研究。通过1H-NMR、13C-NMR、ESI-MS等波谱方法鉴定分离得到的化合物结构,从绵萆薢中分离得到10个化合物,分别鉴定为3个芳香族化合物:diosniponol C（1）、3,5-dih... 详细信息

利用大孔树脂、MCI柱色谱、凝胶柱色谱和制备液相等对绵萆薢化学成分进行研究。通过1H-NMR、13C-NMR、ESI-MS等波谱方法鉴定分离得到的化合物结构,从绵萆薢中分离得到10个化合物,分别鉴定为3个芳香族化合物:diosniponol C（1）、3,5-dihydroxy-4,4'-dimethoxybibenzyl（9）、覆盆子酮（10）;2个皂苷类化合物:甲基原薯蓣皂苷（2）、原纤细薯蓣皂苷（6）;3个二芳基庚烷类化合物:（3R,5R）-3,5-dihydroxy-1,7-bis-（4-hydroxy-3-methoxyphenyl）-heptane 3-O-β-D-glucopyranoside（3）、（3R,5R）-3,5-dihydroxy-1,7-bis（4-hydroxyphenyl） heptane 3-O-β-D-glucopyranoside （4）、（3R,5R）-3,5-dihydroxy-1-（4-hydroxy-3-methoxyphenyl）-7-（4-hydroxyphenyl） heptane 3-β-D-glucopyranoside （5）;1个生物碱类化合物cyclo（l-Pro-l-Leu）(7);1个甾醇类化合物:β-谷甾醇（8）,其中化合物（3～5）、（7）、（9）为首次从绵萆薢药材中分离得到。本研究对绵萆薢70%乙醇提取物化学成分进行系统性分离,丰富了绵萆薢化学成分组成,为绵萆薢的综合开发利用奠定基础。

关键词：绵萆薢化学成分结构鉴定

ONE LINEAR ANALYTIC APPROXIMATION FOR STOCHASTIC INTEGRODIFFERENTIAL EQUATIONS

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Acta Mathematica Scientia 2010年第4期30卷 1073-1085页

作者： svetlana Jankovic Dejan Ilic University of Nis Department of Mathematics

This article concerns the construction of approximate solutions for a general stochastic integrodifferential equation which is not explicitly solvable and whose coeffcients functionally depend on Lebesgue integrals and stochastic integrals with respect to martingales. The approximate equations are linear ordinary stochastic differential equations, the solutions of which are defined on sub-intervals of an arbitrary partition of the time interval and connected at successive division points. The closeness of the initial and approximate solutions is measured in the L^p-th norm, uniformly on the time interval. The convergence with probability one is also given.

关键词： Stochastic integrodifferential equation linear approximation approximate solution L^p-convergence convergence with probability one

Evaluation of Hypervisor Stability towards Insider Attacks

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Journal of Electronic Science and Technology 2016年第1期14卷 37-42页

作者： Roman Kulikov svetlana Kolesnikova the Department of Computer Systems Design and Security National Research University of Information Technology

Virtualization technology plays a key role in cloud ***,the security issues of virtualization tools（hypervisors,emulators,etc.） should be under precise ***,threats of insider attacks are *** virtualization tools and hypervisors have been poorly protected from this type of ***,hypervisor is one of the most critical elements in cloud computing ***,hypervisor vulnerabilities analysis is ***,a formal model of insider attack on hypervisor is ***,on the basis of the formal attack model,we propose a new methodology of hypervisor stability *** this paper,certain security countermeasures are considered that should be integrated in hypervisor software architecture.

关键词： Cloud computing hypervisor insider attack hypervisor stability virtualization virtual machine

The effect of ozone on pine forests in South-Eastern France from 2017 to 2019

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Journal of Forestry Research 2023年第2期34卷 301-315页

作者： Anumol Shashikumar svetlana Bičárová Dalstein-Richier Laurence Groupe International d′Etudes Des Forêts Sud-Européennes(G.I.E.F.S) 69Avenue des Hespérides06300 NiceFrance Institute of Earth Science of the Slovak Academy of Sciences 05960 StaráLesnáTatranskáLomnicaSlovakia

In South-Eastern forests of France,risks linked to the effects of tropospheric ozone(O_(3))are real;its annual impact has been observed specifically near the coastline and in high altitude mountains during the period *** this study,the risk assessment of O_(3)pollutant was carried out using two approaches based on forest response indicators such as O_(3)specific foliar visible injury and by stomatal O_(3)*** O_(3)dose values(POD_(0))were obtained by the DO_(3)SE *** model requires hourly O_(3)concentration for POD_(0)calculation.A modified approach that uses measurements from passive samplers(monthly average O_(3)concentration)was tested for the calculation of POD_(0)and test results showed good agreement with the POD_(0)calculated using hourly O_(3)*** the model input file,the average O_(3)concentration is used for POD_(0),and this could be useful for POD_(0)calculation when the active monitor is *** this study,a flux-based assessment provided better correlation with O_(3)specific leaf injury,which is also *** visible injury in response to O_(3)indicates that Pinus cembra and Pinus halepensis are more affected and therefore more sensitive than Pinus *** POD_(0)and stomatal conductance(Gsto)seem to be induced by environmental factors,primarily rainfall and the soil water potential(fSWP).The correlation between the O_(3)flux metric and environmental variables with forest response indicators by Spearman rank test confirms *** as one of the most sensitive species to O_(3).

关键词： Ozone Foliar visible injury Phytotoxic ozone dose Stomatal conductance DO_(3)SE

Potential use of magnesium industrial waste for synthesis of Li and Mg co-doped LiMn_(2)O_(4)nanoparticles as cathode material for Li-ion batteries:Effect of sintering temperature

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Nano Research 2022年第5期15卷 4500-4516页

作者： Aleksei Llusco Luis Rojas svetlana Ushak Mario Grageda Department of Chemical Engineering and Mineral Processing and Center for Advanced Study of Lithium and Industrial Minerals(CELiMIN) Universidad de AntofagastaAntofagasta 1270300Chile

Potential advantages of active electrode nanomaterials have led to development of high energy and power density lithium-ion(Li-ion)***,under increasing demand for critical resources such as lithium and cobalt,it is necessary to use abundant raw materials,which can be obtained from industrial *** this work,purified Mg(OH)_(2)from waste generated in the production of Li2CO3 with natural brines from the Salar de Atacama(Chile)is used as a doping agent for synthesis of LiMn_(2)O_(4)(LMO)spinel octahedral nanoparticles co-doped with excess Li and *** of a pure cubic spinel phase(Fd3m)takes place at 500℃and sintering temperature effect at 580 and 750℃,thus the elemental composition and the structural,morphological,and electrochemical properties are studied in *** electrochemical performance at room temperature is obtained for Li_(1.03)Mg_(0.05)Mn_(1.92)O_(4)spinel sintered at 750℃with an initial discharge capacity of 121.3 mAh·g^(-1)and capacity retention of 94.0%after 100 cycles at C/3.A locally ordered spinel structure is obtained at 750℃,and doping with Mg^(2+)improves structural *** between both effects resulted in a high Li^(+)diffusion rate(1.29×10^(-9)cm^(2)·s^(-1))significantly improving cycling performance at elevated C-rates in 50℃.

关键词： LiMn_(2)O_(4)(LMO)spinel Mg doped excess Li octahedral nanoparticle industrial waste lithium-ion(Li-ion)batteries

Slow Retrial Asymptotics for a Single Server Queue with Two-Way Communication and Markov Modulated Poisson

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Journal of Systems Science and Systems Engineering 2019年第2期28卷 181-193页

作者： Anatoly Nazarov Tuan Phung-Duc svetlana Paul Institute of Applied Mathematics and Computer Science National Research Tomsk State University 36 Lenina ave. 634050 Tomsk Russian Federation Faculty of Engineering Information and Systems University of Tsukuba 1-1-1 Tennodai Tsukuba Ibaraki 305-8573 Japan

In this paper, we consider an MMPP/M/1/1 retrial queue where incoming fresh calls arrive at the server according to a Markov modulated Poisson process (MMPP). Upon arrival, an incoming call either occupies the server if it is idle or joins a virtual waiting room called orbit if the server is busy. From the orbit, incoming calls retry to occupy the server in an exponentially distributed time and behave the same as a fresh incoming call. After an exponentially distributed idle time, the server makes an outgoing call whose duration is also exponentially distributed but with a different parameter from that of incoming calls. Our contribution is to derive the first order (law of large numbers) and the second order (central lim让 theorem) asymptotics for the distribution of the number of calls in the orb计 under the condition that the retrial rate is extremely low. The asymptotic results are used to obtain the Gaussian approximation for the distribution of the number of calls in the orbit. Our result generalizes earlier results where Poisson input was assumed.

关键词： Retrial queueing system incoming calls and outgoing calls MMPP-process asymptotic analysismethod gaussian approximation

Rickettsia influences thermotolerance in the whitefly Bemisia tabaci B biotype

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Insect Science 2011年第1期18卷 57-66页

作者： Marina Brumin svetlana Kontsedalov Murad Ghanim Department of Entomology Institute of Plant Protection the Volcani Center Bet Dagan Israel

The whitefly Bemisia tabaci harbors Portiera aleyrodidarum, an obligatory symbiotic bacterium, as well as several secondary symbionts, including Rickettsia, Hamiltonella, Wolbachia, Arsenophonus, Cardinium and Fritschea, the function of which is unknown. In Israel, Rickettsia is found in both the B and Q ofB. tabaci biotypes, and while all other secondary symbionts are located in the bacteriomes, Rickettsia can occupy most of the body cavity of the insect. We tested whether Rickettsia influences the biology of B. tabaci and found that exposing a Rickettsia-containing population to increasing temperatures significantly increases its tolerance to heat shock that reached 40~C, compared to a Rickettsia-free population. This increase in tolerance to heat shock was not associated with specific induction of heat-shock protein gene expression; however, it was associated with reduction in Rickettsia numbers as was assessed by quantitative real-time polymerase chain reaction and fluorescence in situ hybridization analyses. To assess the causes for thermotolerance when Rickettsia is reduced, we tested whether its presence is associated with the induction of genes required for thermotolerance. We found that under normal 25℃ rearing temperature, genes associated with response to stress such as cytoskeleton genes are induced in the Rickettsia-containing population. Thus, the presence of Rickettsia in B. tabaci under normal conditions induces the expression of genes required for thermotolerance that under high temperatures indirectly lead to this tolerance.

关键词： cytoskeleton gene expression heat shock symbiont