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Synthesis of PMMA-co-PMAA Copolymer Brush on Multi-Wall Carbon Nanotubes

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Journal of Surface Engineered Materials and Advanced Technology 2012年第3期2卷 221-226页

作者： petr Slobodian petr Svoboda Pavel Riha Roman Boruta petr Saha Centre of Polymer Systems University Institute Tomas Bata University Zlin Czech Republic Department of Polymer Engineering Faculty of Technology Tomas Bata University Zlin Czech Republic 4Institute of Hydrodynamics Academy of Sciences Prague Czech Republic Institute of Hydrodynamics Academy of Sciences Prague Czech Republic. Polymer Centre Faculty of Technology Tomas Bata University Zlin Czech Republic

Poly(methyl methacrylate)/poly(methacrylamide) copolymer (PMMA-co-PMAA) was synthesized by a free radical copolymerization of MMA and MAA monomers in methylethyl ketone using AIBN as radical initiator. Multi-wall carbon nanotubes (MWCNT) were oxidized in KMnO4 acidic suspension. Carboxyl groups on the surface oxidized MWCNT were reacted with primary amide group of PMMA-co-PMAA copolymer in MEK solution under ultrasound to form polymer brush on the surface of MWCNT. With the help of TG analyses the amount of covalently grafted PMMA-co-PMAA copolymer onto MWCNT surface was determined as ?47 wt%. TEM analyses identified thin co-polymer layer adhered onto MWCNT surface with average thickness ?5 nm.

关键词： Carbon Nanotubes Functionalization PMMA PMAA Polymer brush

An Integrated Oil Production Enhancement Technology Based on Waterflooding Energy Recovery

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Fluid Dynamics & Materials Processing 2023年第2期19卷 285-301页

作者： Aleksandr Lekomtsev vitaliy Bakaneev Ivan Stepanenko petr Maximov Yulia Rozhkova Alexey Dengaev Wanli Kang Perm National Research Polytechnic University Perm614990Russian Department of Oil Field Development and Operation Gubkin Russian State University of Oil and GasMoscow119991Russia China University of petroleum(East China) Qingdao266000China

A new integrated oil production enhancement technology based on water-flooding energy recovery is *** providing an extensive review of the existing scientific and technical literature on this subject,the proposed integrated technology is described together with the related process flow diagram,the criteria used to select a tar-get facility for its implementation and the outcomes of the laboratory studies conducted to analyze emulsion formation and separation ***,the outcomes of numerical simulations performed using Ansys CFX software are also *** to these results,using the proposed approach the incremental oil production may reach 1.2 t/day(with a 13%increase)and more,even at low flow rates(less than 10 t/day),thereby providing evidence for the benefits associated with this integrated technology.

关键词： Oil production jet pump waterflooding system energy recovery Ansys CFX

Comparison of the Ergonomic Characteristics of Forwarders with Stationary and Rotating Cabins

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Journal of Agricultural Science and Technology(B) 2014年第6期4卷 476-484页

作者： petr Filo Department of Forest and Forest Products Technology Faculty of Forestry and Wood Technology Mendel University in Brno Brno61300 Czech Republic

The research of the ergonomic parameters of two tested forwarders was based on the measurement of a variability of physiological functions of the operator during one work shift. The research included a series of six measurements, each lasting l h and starting at 5：00, 12：00 and 17：00 O＇clock. The measured operator was at all times the same person. We had a hypothesis that the rate of the measured variability would have to do with the following four factors： forwarder cabin type, terrain character, fatigue during the work shift and work at daylight or in dark. Main findings are described below： during his work with a fixed type of the forwarder cab, the operator＇s brain waves at the frequency of Gamma, high Beta, Beta and Alpha reached statistically significantly higher average values than during his work with a rotating cab. With a higher degree of terrain roughness and in the forwarder with the rotating cab, the operator showed a significantly higher frequency and lower amplitude of respiration. At the beginning of the work shift, the tension of muscles in the operator＇s neck was at the significantly lowest level. In the afternoon, at the end of the work shift, the level of muscle tension was the highest. The “daylight/dark” work had a significantly highest impact on volume changes in the amplitude （strength） of blood pulse and on the skin conductance level. All research factors explained together 15%-65% of the variability of physiological functions.

关键词： Forwarder cabin ergonomic parameters operator psycho-physiological functions

Design and experiment of fuzzy-PID based tillage depth control system for a self-propelled electric tiller

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International Journal of Agricultural and Biological Engineering 2023年第4期16卷 116-125页

作者： Maohua Xiao Ye Ma Chen Wang Junyun Chen Yejun Zhu petr Bartos Guosheng Geng College of Engineering Nanjing Agricultural UniversityNanjing 210031China Faculty of Agriculture University of South BohemiaStudentska 1668Czech

The research on the self-propelled electric tiller is vital for further improving the quality and efficiency of greenhouse rotary tillage operation,reducing the work intensity and operation risk of operators,and achieving environmentally friendly *** of the existing self-propelled tillers rely on manual adjustment of the tillage ***,the consistency and stability of the tillage depth are difficult to *** this study,the automatic control method of tillage depth of a self-propelled electric tiller is investigated.A method of applying the fuzzy PID(Proportional Integral Derivative)control method to the tillage depth adjustment system of a tiller is also proposed to realize automatic *** system uses the real-time detection of the resistance sensor and angle *** controller runs the electronically controlled hydraulic system to adjust the force and position *** fuzzy control algorithm is used in the operation error control to realize the double-parameter control of the tillage *** simulation and experimental verification of the system are *** show that the control system applying fuzzy PID can improve the soil breaking rate by 3%in the operation process based on reducing the stability variation of tillage depth by 24%.The control strategy can reach the set value of tillage depth quickly and *** can also meet the requirement of tillage depth consistency during the operation.

关键词： Fuzzy PID Self-propelled electric tiller Tillage depth Electro-controlled hydraulic system Comprehensive adjustment of force and position

Pathological changes in the cellular structures of retina and choroidea in the early stages of alloxan-induced diabetes

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World Journal of Diabetes 2018年第12期9卷 239-251页

作者： Irina Danilova Svetlana Medvedeva Svetlana Shmakova Margarita Chereshneva Alexey Sarapultsev petr Sarapultsev Department of Biology and Fundamental Medicine Institute of Natural Sciences and Mathematics Ural Federal University Named After the First Pres.of Russia B.N.Yeltsin Laboratory of Morphology and Biochemistry Institute of Immunology and Physiology Ural Division of Russian Academy of Sciences Laboratory of Immunophysiology and Immunopharmacology Institute of Immunology and Physiology Ural Division of Russian Academy of Sciences Institute of Chemical Engineering Ural Federal University Named After the First Pres. of Russia B.N. Yeltsin Laboratory of Immu-nophatophysiology Institute of Immunology and Physiology Ural Division of Russian Academy of Sciences

AIM To investigate the temporal sequence of pathological changes in the cellular structures of retina and choroidea in the early stages of diabetes in laboratory *** Experimental type 1 diabetes was modeled by three intraperitoneal injections of an alloxan solution into 30 male nonlinear rats at 16 wk of age. The 30 th and 60 th days from the final alloxan injection were chosen as the endpoints. Light and electron microscopy and morphometric and immunohistochemical studies were performed on histological slices of eyeballs from experimental *** Diabetic disturbances progressed to 60 d of the experiment. Thus, in the retina, a partial destruction of photoreceptors accompanied by interstitial edema was observed. The morphometric analysis revealed a reduction in the thickness of the retina. A reduction in the number of blood vessels of the choroid with disturbances of the endothelial cells and the vascular walls and a persistent reduction in the number of melanocytes were observed. The number of proliferating Ki-67 positive cells decreased, and the number of macrophages increased with diabetes *** The starting point in the development of destructive changes involves early reduction in the number of melanocytes of the choroidea and alterations in the retinal pigment epithelium.

关键词： Alloxan Diabetes Diabetic retinopathy Early stage Morphology Histological changes

Applying Double Skin Facade with ETFE Membrane Assembly for Energy Saving and Acoustic Protection for the Building of the Czech Institute of Informatics,Robotics and Cybernetics in Prague

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Journal of Civil Engineering and Architecture 2019年第3期13卷 178-185页

作者： petr Franta Architects&Assoc. Ltd.PragueCzech Republic Czech Institute of Informatics Robotics and Cybernetics-Czech Technical UniversityPragueCzech Republic

Multidisciplinary, integrated planning approach by architects, engineers, scientists and manufacturers to reduce energy consumption of buildings. The CIIRC Complex, located on the main campus of Czech Technical University in Prague consists of two buildings, newly constructed building and adaptive reuse of existing building. CIIRC—Czech Institute of Informatics, Robotics and Cybernetics is a contemporary teaching facility of new generation and use for scientific research teams. New building has ten above-ground floors, on the bottom 4 floors of laboratories, scientist modules, classrooms, above are offices, meeting rooms, teaching and research modules for professors and students. Offices of the rector are on the last two floors of the building. On the top floor is congress type auditorium, in the basement is fully automatic car park. Double skin pneumatic cushions facade. In the project are introduced series of architectural and technical features and innovations. Probably the most visible is the double skin facade facing south-transparent double layer membrane ETFE (Ethylen-TetraFluorEthylen) cushions with triple glazed modular system assembly. Acting as solar collector, recuperating of hot air on the top floors, saving up to 30% of an energy consumption.

关键词： Double skin façade as solar collector ETFE membrane cushions as outer skin air-recuperation from façade(top floors).

Biochar surface functional groups as affected by biomass feedstock, biochar composition and pyrolysis temperature

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Carbon Resources Conversion 2021年第1期4卷 36-46页

作者： Rainer Janu verena Mrlik Doris Ribitsch Jakub Hofman petr Sedlácek Lucie Bielsk Gerhard Soja AIT Austrian Institute of Technology GmbH Konrad Lorenz-Str.243430 TullnAustria University of Natural Resources and Life Sciences Institute of Environmental BiotechnologyKonrad Lorenz-Str.203430 TullnAustria Masaryk University Faculty of ScienceRECETOXKamenice 753/562500 BrnoCzech Republic Brno University of Technology Materials Research CentrePurkyňova 464/11861200 BrnoCzech Republic University of Natural Resources and Life Sciences Institute for Chemical and Energy EngineeringMuthgasse 1071190 WienAustria

By testing 92 different biochars,this study had the objective to determine the relations between simple physico-chemical characteristics of biochar(elemental composition,ash fraction,specific surface area,process parameters)and infrared sorption characteristics revealing the presence of specific functional *** results of Diffusive Reflection Fourier Transformation Infrared Spectroscopy were statistically analyzed with multiple linear regression techniques and Principal Component Analysis(PCA)with the biochar characterization parameters as model *** dominant parameters affecting the functional group signals were the pyrolysis temperature,the H/C-ratio and specific surface area of the biochar and the ash *** models were able to explain 60-90%of data variance for specific peaks in the *** application of PCA could further reduce the input parameters to three main factors explaining 70.8%of total data *** of the first two main factors showed the similarity of infrared spectra of biochars produced at 300 and 450℃,whereas a pyrolysis temperature of 600℃ lead to a partial and a 750℃ to a nearly complete loss of biochar surface functional groups.

关键词： FTIR DRIFTS Spectroscopy Characterization Carbonization

Anorectal hemangioma, a rare cause of lower gastrointestinal bleeding, treated with selective embolization: A case report

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World Journal of Gastrointestinal Surgery 2024年第8期16卷 2735-2741页

作者： Barbora Pospisilova Jaromir Frydrych Antonin Krajina JuliusÖrhalmi Ivana M Kajzrlikova petr vitek Department of Internal Medicine Hospital in Frydek-MistekFrydek-Mistek 73801Czech Republic Department of Radiodiagnostic Hospital in Jablonec nad NisouJablonec nad Nisou 46601Czech Republic Department of Radiology University Hospital Hradec KraloveHradec Kralove 50005Czech Republic Department of Surgery Hospital HoroviceHorovice 26831Czech Republic Faculty of Medicine University of OstravaOstrava 70300Czech Republic

BACKGROUND Anorectal hemangioma is a rare and frequently misdiagnosed cause of lower gastrointestinal(GI)***,we present a minimally invasive therapy with selective *** SUMMARY A 21-year-old male patient experienced painless rectal bleeding since childhood and was treated for ulcerative *** studies later revealed specific characteristics for vascular lesions-anorectal *** severity of rectal bleeding caused symptomatic anemia and possible surgical treatment was asso-ciated with a high risk of fecal ***,we present selective emboli-zation,a minimally invasive therapeutic approach that is proven as an alternative therapeutic method of *** patient significantly improved temporarily and had a small ischemic ulcer,which healed with a control colonoscopy and deve-loped no *** Awareness of the clinical and radiological features of GI hemangiomas may help improve diagnostics and avoid inappropriate therapeutic procedures.

关键词： Hemangioma vascular malformation Gastrointestinal hemorrhage Rectal bleeding Phlebolith Selective embolization Case report

Morphological characteristics of blood cells in monitor lizards:is erythrocyte size linked to actual body size?

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Integrative Zoology 2013年第1期8卷 39-45页

作者： petra FRÝDLOvÁ Jan HNÍZDO Lenka CHYLÍKOvÁ OlgaŠIMKOvÁ veronika CIKÁNOvÁ petr vELENSKÝ Daniel FRYNTA Department of Zoology Charles University in PraguePragueCzech Republic Animal Clinic PragueCzech Republic Prague Zoo PragueCzech Republic

Blood cell morphology and count are not uniform across ***,between-species comparisons revealed that the size of red blood cells is associated with body size in some lizard taxa,and this finding was interpreted in the context of the metabolic *** the present study,we examined the numbers and the size of blood cells in 2 species of monitor lizards,the mangrove-dwelling monitor(varanus indicus)and the savannah monitor(***),and we compared these traits in individuals of different body *** results revealed that during the course of ontogeny,the size of red blood cells increases with body *** the mass-specific metabolic rate decreases with body size and the cell volume-to-surface ratio decreases with the cell size,changes in the erythrocyte size might be the result of oxygen transport adjustment.

关键词： blood parameters body size erythrocyte size metabolic theory varanidae