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Effect of Surfactant Stabilizers on the Distribution of Carbon Nanotubes in Aqueous Media

Journal of Wuhan University of Technology(Materials Science) 2018年第3期33卷 533-536页

作者： Yury N Tolchkov Zoya A Mikhaleva r D A Sldozian nariman r memetov Alexey G Tkachev Department of Technology and Methods of Nanoproducts Manufacturing Tambov State Technical University

The results of a study on the homogeneity of suspensions are described considering the effect of different types of surfactant stabilizers and their concentrations on the uniform distribution of a carbon nanotubes（CNTs）-based modifying additive to construction materials in an aqueous medium. This problem was solved herein by using surfactants and ultrasound. The sonication treatment of CNTs particle agglomerates allowed for dispersing their globules and achieving a 15-20-fold decrease in their average size, for which it became possible to make better use of the CNTs as cement modifier. As a result of the experimental studies carried out, the effect of the surfactant type and concentration promoting uniform distribution of the CNTs in the bulk of the suspension and, correspondingly, in the structural composite matrix was revealed. The CNTs-based additive improved the physical-mechanical and operational characteristics of the material.

关键词： carbon nanotubes nanomodification composite construction materials surfactants

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Estimating Water retention with Pedotransfer Functions Using Multi-Objective Group Method of Data Handling and ANNs

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Pedosphere 2011年第1期21卷 107-114页

作者： H.BAYAT M.r.NEYSHABOUrI K.MOHAMMADI N.nariman-ZADEH Department of Soil Science Faculty of AgricultureBu Ali Sina University Department of Soil Science Faculty of AgricultureTabriz University Department of Irrigation and Drainage Engineering Tarbiat Modares University Department of Mechanical Engineering Engineering FacultyGuilan University

Pedotransfer functions(PTFs) have been developed to estimate soil water retention curves(SWrC) by various *** this study PTFs were developed to estimate the parameters(θ s,θ r,α and λ) of the Brooks and Corey model from a data set of 148 *** and aggregate size distribution fractal parameters(PSDFPs and ASDFPs,respectively) were computed from three fractal models for either particle or aggregate size *** most effective model in each group was determined by sensitivity *** with the other variables,the selected fractal parameters were employed to estimate SWrC using multi-objective group method of data handling(mGMDH) and different topologies of artificial neural networks(ANNs).The architecture of ANNs for parametric PTFs was different regarding the type of ANN,output layer transfer functions and the number of hidden *** parameter was estimated using four PTFs by the hierarchical entering of input variables in the *** inclusion of PSDFPs in the list of inputs improved the accuracy and reliability of parametric PTFs with the exception of θ *** textural fraction variables in PTF1 for the estimation of α were replaced with PSDFPs in *** use of ASDFPs as inputs significantly improved α estimates in the *** result highlights the importance of ASDFPs in developing parametric *** mGMDH technique performed significantly better than ANNs in most PTFs.

关键词：人工神经网络土壤水分特征曲线参数估计数据处理多目标保水功能土壤转换函数分形模型

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Design and performance analysis of position-based impedance control for an electrohydrostatic actuation system

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Chinese Journal of Aeronautics 2018年第3期31卷 584-596页

作者： Yongling FU Xu HAN nariman SEPEHrI Guozhe ZHOU Jian FU Liming YU rongrong YANG School of Mechanical Engineering and Automation Beihang University Beijing 100083 China Department of Mechanical Engineering University of Manitoba Manitoba R3T 2N2 Canada China Academy of Launch Vehicle Technology Beijing 100076 China Flying College Beihang University Beijing 100083 China

Electrohydrostatic actuator（EHA） is a type of power-by-wire actuator that is widely implemented in the aerospace industry for flight control, landing gears, thrust reversers, thrust vector control, and space robots. This paper presents the development and evaluation of positionbased impedance control（PBIC） for an EHA. Impedance control provides the actuator with compliance and facilitates the interaction with the environment. Most impedance control applications utilize electrical or valve-controlled hydraulic actuators, whereas this work realizes impedance control via a compact and efficient EHA. The structures of the EHA and PBIC are firstly introduced. A mathematical model of the actuation system is established, and values of its coefficients are identified by particle swarm optimization. This model facilitates the development of a position controller and the selection of target impedance parameters. A nonlinear proportional-integral position controller is developed for the EHA to achieve the accurate positioning requirement of PBIC. The controller compensates for the adverse effect of stiction, and a position accuracy of 0.08 mm is *** experimental results are presented to verify the applicability of PBIC to the EHA. The compliance of the actuator is demonstrated in an impact test.

关键词： Actuation system Aerospace Electrohydrostatic actuator Force control Nonlinear dynamics Particle swarm optimization Position control

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Climate Change and Its Impact on Brown Bear Distribution in Iran

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Journal of Zoological research 2022年第1期4卷 1-11页

作者： Sahar roshan Ara Sohrab Ashrafi roghayeh Garmaeepour Mohammad Zarrintab nariman Askaripour Sorour Esfandeh Department of Environmental Sciences Faculty of Natural ResourcesUniversity of TehranIran ARTICLE

Climate change is one of the threats in the recent century,affecting biodiversity directly and *** the patterns of species distribution is one of useful tools for predicting the impacts of climate change on endangered *** bear(Ursus arctos)plays an important role as a focal species in mountainous *** study was aims to investigate the effects of future climate changes on the distribution of this species using an ensemble modeling method in *** this purpose five algorithms including MAXENT,rF,MArS,GAM,GLM and BrT were used to predict the distribution of the species in the present climatic conditions as well as in the 2050s and *** results showed that temperature and precipitation were two main factors in the distribution of brown bears in *** the distribution of the brown bear in the future showed that suitability of its habitat will decrease in the western and central parts and increase in the northern *** a shift toward higher altitude will be expected for brown bear in the ***,in this condition it is imperative to upgrade the extent of protected areas for better conservation of brown bear.

关键词： Iran Ursus arctos Species distribution modeling r software Predicting

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由有胚胎的干细胞的熔化的 reprogramming 体的房间不在老鼠引起 Dlk1-Dio3 区域的 silencing

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World Journal of Stem Cells 2012年第8期4卷 87-93页

作者： nariman r Battulin Anna A Khabarova Ul’yana A Boyarskikh Aleksey G Menzorov Maxim L Filipenko Oleg L Serov Institute of Cytology and Genetics SD rAS Lavrentyeva 10 Novosibirsk 630090 Russian Institute of Chemical Biology and Basic Medicine SD rAS Lavrentyeva 8 Novosibirsk 630090 Russian

AIM:To examine the imprinted Dlk1-Dio3 locus in pluripotent embryonic stem(ES)cell/fibroblast hybrid ***:Gtl2,rian,and Mirg mrNA expression in mouse pluripotent ES cell/fibroblast hybrid cells was examined by real-time reverse transcription-polymerase chain *** and bisulfate sequencing were used to determine the DNA methylation level of the Dlk1-Dio3 locus imprinting control region. rESULTS:The selected hybrid clones had a near-tetraploid karyotype and were highly pluripotent judging from their capacity to generate chimeric embryos and adult *** data clearly demonstrate that Gtl2,rian,and Mirg,which are imprinted genes within the Dlk1-Dio3 locus,are active in all examined ES cell/fibroblast hybrid *** spite of interclonal variability,the expression of the imprinted genes is comparable to that of ES cells and *** analysis of the DNA methylation status of the intergenic differentially methylated region(IG DMr)within the Dlk1-Dio3 locus by pyrosequencing and bisulfite sequencing clearly showed that the DNA methylation status of the imprinted region in the tested hybrid clones was comparable to that of both ES cells and ***:reprogramming process in a hybrid cell system is achieved without marked alteration of the imprinted Dlk1-Dio3 locus.

关键词： Cell fusion Embryonic stem cells reprogramming Pluripotency Imprinted Dlk1-Dio3 region DNA methylation

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Spectrophotometric Investigation of Complex Formation of Ge（IV） with Bis（2,3,4-Trigidroksifenilazo） Benzidine in the Presence of Cationic Surfactants Active Substances

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Journal of Chemistry and Chemical Engineering 2014年第1期8卷 21-24页

作者： Mardanova Samira rafiq Alieva rafiqa Alirza Bahmanova Fidan nariman Chyragov Famil Musa Ganja State University Ganja AZ-2000 Azerbaidjan Baku State University Baku AZ-1148 Azerbaidjan

It is investigated the interaction of Ge(IV) with bis(2,3,4-trigodroksifenolazo) benzidine (r) in the presence of KSAS (cationic surface active substances)-CPCl (cetylpyridinium chloride), CPBr (cetylpyridinium bromide) and CTMABr (cetyltrimethylammonium bromide). It is studied the effect pH, time on the formation of ternary complexes. It is determinated of molar absorption coefficients and stability constants of germanium. Binary (Ge-r) and triple (Ge-r-CPCl, Ge-r-CPBr, Ge-r-C M Br) complex form at pH 4 and pH 1, respectively. The composition proportion of binar system is 1 2 and the composition proportion triple complex is 1 1 2. The concentration interval of germanium which obeying beer low in the Ge-r 0.12-2.92 mkq/mL, in the Ge-r-CPCl is 0.04-1.46 mkq/mL, in the Ge-r-CPBr is 0.00-1.00 mkq/mL and in the Ge-r-C M Br is 0.00-1.00 mkq/mL. Molar absorbtivities of complexes are 45,000, 57,000, 59,000 and 60,000, respectively. The effect of interfering ions and masking agents has been learned. Stability constants of complexes have been determined lgK1 = 7.21 0.06 (Ge-r), lgK1 = 12.08 0.05 (Ge-r-CPCl), lgK1 = 12.12 0.07 (Ge-r-CPBr) and lgK1 = 12.85 0.06 (Ge-r-C M Br). It is developed highly selective method of photometric determination of trace amounts of Ge(IV) in petroleum coke.

关键词：阳离子表面活性剂表面活性物质三元复合物联苯胺分光光度法十六烷基三甲基溴化铵氯化十六烷基吡啶溴化十六烷基吡啶

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