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Structural and optical properties of nanostructured copper sulfide semiconductor synthesized in an industrial mill

Frontiers of Chemical Science and Engineering 2019年第1期13卷 164-170页

作者： Marcela Achimovicova Erika Dutkova Erika Tothova Zdenka Bujnakova jaroslav Briancin Satoshi Kitazono Institute of Mineral and Waste Processing Waste Disposal and Geomechanics Clausthal University of Technology Clausthal 38678 Germany Institute of Geotechnics Slovak Academy of Sciences Kosice 04001 Slovakia Nakase Refinery Nihon Seiko Co. Ltd. Yabu-shi Hyogo 667-1111 Japan

Chalcogenide nanostructured semiconductor, copper sulfide (CuS) was prepared from copper and sulfur powders in stoichiometric ratio by a simple, fast, and convenient one-step mechanochemical synthesis after 40 min of milling in an industrial eccentric vibratory mill. The kinetics of the mechanochemical synthesis and the influence of the physical properties of two Cu powder precursor types on the kinetics were studied. The crystal structure, physical properties, and morphology of the product were characterized by X-ray diffraction (XRD), the specific surface area measurements, particle size distribution and scanning electron microscopy. The XRD analysis confirmed the hexagonal crystal structure of the product-CuS (covellite) with the average size of the crystallites 11 nm. The scanning electron microscopy analysis has revealed that the agglomerated grains have a plate-like structure composed of CuS nanoparticles. The thermal analysis was performed to investigate the thermal stability of the mechanochemically synthesized CuS. The optical properties were studied using UV-Vis and photoluminescence spectroscopy. The determined optical band gap energy 1.80 eV responds to the value of the bulk CuS, because of agglomerated nanoparticles. In addition, a mechanism of CuS mechanochemical reaction was proposed, and the verification of CuS commercial production was performed.

关键词： copper sulfide industrial mechanochemical synthesis thermal analysis optical properties

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Augmented Node Placement Model in t-WSN Through Multiobjective Approach

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Computers, Materials & Continua 2021年第12期69卷 3629-3644页

作者： Kalaipriyan Thirugnansambandam Debnath Bhattacharyya jaroslav Frnda Dinesh Kumar Anguraj Jan Nedoma School of Computer Science and Engineering VIT UniversityChennai CampusTamilnaduIndia Department of Computer Science and Engineering Koneru Lakshmaiah Education FoundationVaddeswaramGunturIndia Department of Quantitative Methods and Economic Informatics Faculty of Operation and Economics of Transport and CommunicationsUniversity of Zilina01026 ZilinaSlovakia Department of Telecommunications Faculty of Electrical Engineering and Computer ScienceVSB-Technical University of Ostrava70833 Ostrava-PorubaCzech Republic

In Wireless Sensor Network(WSN),coverage and connectivity are the vital challenges in the target-based *** linear objective is to find the positions to cover the complete target nodes and connectivity between each sensor for data forwarding towards the base station given a grid with target points and a potential sensor placement *** this paper,a multiobjective problem on target-based WSN(t-WSN)is derived,which minimizes the number of deployed nodes,and maximizes the cost of coverage and sensing *** Evolutionary-based Non-Dominated Sorting Genetic Algorithm-II(NSGA-II)is incorporated to tackle this multiobjective problem *** problems are intended to solve different objectives of a problem ***-inspired algorithms address the NP-hard problem most effectively in recent *** NSGA-II,the Non-Dominated sorting preserves the better solution in different objectives simultaneously using dominance *** the diversity maintenance phase,density estimation and crowd comparison are the two components that balance the exploration and exploitation phase of the *** of NSGA-II on this multiobjective problem is evaluated in terms of performance indicators Overall Non-dominated Vector Generation(ONGV)and Spacing(SP).The simulation results show the proposed method performs outperforms the existing algorithms in different aspects of the model.

关键词： Focused wireless sensor network m-coverage k-connectivity problem non-dominated sorting NSGA-II

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Optimization of Root Section for Ultra-long Steam Turbine Rotor Blade

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Journal of Thermal Science 2018年第2期27卷 95-102页

作者： Jindrich Hala Martin Luxa David Simurda marek Bobcik Ondrej Novak Bartolomej Rudas jaroslav Synac Institute of Thermomechanics of The Czech Academy of Sciences Prague Czech Republic Doosan Skoda Power Ltd Pilsen Czech Republic Faculty of Mechanical Engineering University of West Bohemia Pilsen Czech Republic

This study presents the comparison of aerodynamic performances of two successive designs of the root profiles for the ultra-long rotor blade equipped with a straight fir-tree dovetail. Since aerodynamic and strength requirements laid upon the root section design are contradictory, it is necessary to aerodynamically optimize the design within the limits given by the foremost strength requirements. The most limiting criterion of the static strength is the size of the blade cross-section, which is determined by the number of blades in a rotor and also by the shape and size of a blade dovetail. The aerodynamic design requires mainly the zero incidence angle at the inlet of a profile and in the ideal case ensures that the load does not exceed a limit load condition. Moreover, the typical root profile cascades are transonic with supersonic exit Math number, therefore, the shape of a suction side and a trailing edge has to respect transonic expansion of a working gas. In this paper, the two variants of root section profile cascades are compared and the aerodynamic qualities of both variants are verified using CFD simulation and two mutually independent experimental methods of measurements （optical and pneumatic）.

关键词： steam turbine blade cascade root section

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SP-DSTS-MIMO Scheme-Aided H.266 for Reliable High Data Rate Mobile Video Communication

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Computers, Materials & Continua 2023年第1期74卷 995-1010页

作者： Khadem Ullah Nasru Minallah Durre Nayab Ishtiaque Ahmed jaroslav Frnda Jan Nedoma Department of Computer Systems Engineering University of Engineering and Technology PeshawarPeshawar25000Pakistan National Centre in Big Data and Cloud Computing University of Engineering and Technology Peshawar(NCBC-UETP)Peshawar25000Pakistan Department of Quantitative Methods and Economic Informatics Faculty of Operation and Economics of Transport and CommunicationsUniversity of Zilina01026ZilinaSlovakia Department of Telecommunications Faculty of Electrical Engineering and Computer ScienceVSB-Technical University of OstravaOstrava-PorubaCzech Republic

With the ever growth of Internet users,video applications,and massive data traffic across the network,there is a higher need for reliable bandwidth-efficient multimedia *** Video Coding(VVC/H.266)is finalized in September 2020 providing significantly greater compression efficiency compared to Highest Efficient Video Coding(HEVC)while providing versatile effective use for Ultra-High Definition(HD)*** article analyzes the quality performance of convolutional codes,turbo codes and self-concatenated convolutional(SCC)codes based on performance metrics for reliable future video *** advent of turbo codes was a significant achievement ever in the era of wireless communication approaching nearly the Shannon *** codes are operated by the deployment of an interleaver between two Recursive Systematic Convolutional(RSC)encoders in a parallel *** RSC encoders may be operating on the same or different architectures and code *** proposed work utilizes the latest source compression standards H.266 and H.265 encoded standards and Sphere Packing modulation aided differential Space Time Spreading(SP-DSTS)for video transmission in order to provide bandwidth-efficient wireless video ***,simulation results show that turbo codes defeat convolutional codes with an averaged E_(b)/N_(0) gain of 1.5 dB while convolutional codes outperformcompared to SCC codes with an E_(b)/N_(0) gain of 3.5 dBatBit ErrorRate(BER)of 10−*** Peak Signal to Noise Ratio(PSNR)results of convolutional codes with the latest source coding standard of H.266 is plotted against convolutional codes with H.265 and it was concluded H.266 outperform with about 6 dB PSNR gain at E_(b)/N_(0) value of 4.5 dB.

关键词： H.265 RSC turbo codes SCC SP-DSTS BP-CNN BER PSNR

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Footfall patterns of a runner with an Achilles tendon rupture

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Journal of Sport and Health Science 2017年第4期6卷 498-502页

作者： Daniel Jandacka David Zahradnik Roman Farana jaroslav Uchytil Joseph Hamill Department of Human Movement Studies Human Motion Diagnostic Center University of Ostrava Department of Kinesiology University of Massachusetts

Purpose: This study aims to compare the load and the length of previously ruptured and healthy Achilles tendon(AT) of a recreational runner who used different footfall patterns on each limb during ***: A 41-year-old recreational athlete with a ruptured AT participated in this report. Two force plates and a high-speed motion capture system were used to collect ground reaction force and kinematic data in shod and barefoot running conditions. AT length was measured using ultrasonography and an infrared camera system. AT force was estimated as the active plantar flexion moment divided by AT moment arm during stance ***: The participant used a rearfoot pattern on the affected limb and a forefoot/midfoot pattern on the unaffected limb during shod running,and a forefoot/midfoot pattern during barefoot running. There was no difference between the length of the affected and the unaffected AT. During shod running, the maximal AT force and loading rate were lower in the affected AT versus the unaffected AT. During barefoot running, the affected maximal AT force and loading rate were greater than the unaffected ***: Footfall patterns can be an adaptation to reduce the loading on a previously injured AT. It appears that runners may consider using a rearfoot footfall pattern during running to reduce the stress on the AT.

关键词： Achilles tendon Calcaneus Footfall patterns Injury Running Tendon length

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Thermostability of montmorillonitic clays

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China Foundry 2014年第3期11卷 201-207页

作者： Petr Jelínek Stanislaw M.Dobosz jaroslav Beňo Katarzyna Major-Gabrys VSB–Technical University of Ostrava Faculty of Metallurgy and Material Engineering Department of Metallurgy and Foundry Engineering Czech Republic AGH University of Science and Technology Faculty of Foundry Engineering Department of Moulding Materials Mould Technology and Foundry of Non-ferrous Metals Al. Mickiewicza 30 30-059 Krakow Poland

Bentonite is one of the most widespread used clays connected with various applications. In the case of foundry technology, bentonite is primarily used as a binder for mold manufacture. Thermal stability of bentonites is a natural property of clay minerals and it depends on the genesis, source and chemical composition of the clay. This property is also closely connected to bentonite structure. According to DTA analysis if only one peak of dehydroxylation is observed(about 600 oC), the cis- isomerism of bentonite is expected, while two peaks of de-hydroxylation(about 550 and 850 oC) are expected in the trans- one. In this overview, the bentonite structure, the water – bentonite interaction and the swelling behavior of bentonite in connection with the general technological properties of bentonite molding mixture are summarized. Further, various types of methods for determination of bentonite thermostability are discussed, including instrumental analytical methods as well as methods that employ evaluation of various technological properties of bentonite binders and/or bentonite molding mixtures.

关键词： bentonite thermostability binder clay

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An Artificial Heart System for Testing and Evaluation of Cardiac Pacemakers

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Computers, Materials & Continua 2022年第12期73卷 6269-6287页

作者： Martin Augustynek Jan Kubicek jaroslav Thomas Marek Penhaker Dominik Vilimek Michal Strycek Ondrej Sojka Antonino Proto Department of Cybernetics and Biomedical Engineering Faculty of Electrical Engineering and Computer ScienceVSB-Technical University of Ostrava17.Listopadu 15Ostrava–Poruba70800Czech Republic

The usability assessment of a pacemaker is a complex task where the dedicated programmer for testing programmed algorithms is *** paper provides the outcomes of development and complex testing of the artificial cardiac system to evaluate the pacemaker’s *** this work,we used the modular laboratory platform ELVIS II and created graphical user interface in LabVIEW programming *** electrical model of the heart allows signals generation(right atrium,right ventricle)and the monitoring of the stimulation *** LabVIEW user interface allows to set the parameters of the generated signals and the simulation of the cardiac rhythm disorders as well as the monitoring and visualization of the pacemaker behavior in *** results demonstrate the capability of proposed system to evaluate the paced and sensed *** proposed solution allows the scientists to test the behavior of any cardiac pacemaker for its pre-programmed settings and pacing *** addition,the proposed system can simulate various disorders and test cardiac pacemakers in different working modes.

关键词： Artificial heart cardiac conduction system electrical cardiac stimulation pacemaker

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Acute appendicitis in a patient after a uterus transplant: A case report

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World Journal of Clinical Cases 2019年第24期7卷 4270-4276页

作者： Jakub Kristek Michal Kudla jaroslav Chlupac Robert Novotny Tomas Mirejovsky Libor Janousek Jiri Fronek Department of Transplant Surgery Institute for Clinical and Experimental MedicinePrague 14021Czech Republic Department of Anatomy Second Faculty of MedicineCharles UniversityPrague 15006Czech Republic Department of Clinical and Transplant Pathology Institute for Clinical and Experimental MedicinePrague 14021Czech Republic First Faculty of Medicine Charles UniversityPrague 12108Czech Republic

BACKGROUND Acute appendicitis in a solid organ transplant recipient is a rare occurrence, and experience remains limited. Appendicitis in uterine transplant recipients has never been reported. Immunocompromised patients with acute abdomen often present late and with attenuated symptoms. The differential diagnosis in a transplanted patient is broad and challenging due to possible existing complications associated with the graft, effects of immunosuppression, and altered anatomical *** SUMMARY A 26-year-old woman suffering from absolute uterine factor infertility received a uterus transplant. In the post-transplant period, she suffered from leukopenia and recurrent acute cellular rejection. Her compliance was suboptimal. She travelled to an exotic destination despite the physician's recommendation not to do so. Following her vacation, she presented with abdominal discomfort, nausea and diarrhoea. There was no sign of acute abdomen;the abdominal ultrasound was negative on day 0. Clostridium difficile colitis was verified and treated with perorally administered vancomycin. On day 4, the discomfort changed to pain;the ultrasound scan revealed a finding suggestive of appendicitis. Surgical exploration revealed perforated appendicitis, and appendectomy was *** a surgical point of view, the patient's follow-up was uneventful. The patient underwent a successful embryo transfer 6 months after the appendectomy. The patient gave birth to a healthy boy at the 35 th week of *** A high index of suspicion of an atypical course and symptomatology of acute abdomen should be maintained in immunosuppressed patients.

关键词： Uterus Organ transplantation Noncompliance Acute abdomen Colitis Differential diagnosis Case report

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Small intestinal bacterial overgrowth syndrome

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World Journal of Gastroenterology 2010年第24期16卷 2978-2990页

作者： Jan Bures Jiri Cyrany Darina Kohoutova Miroslav Frstl Stanislav Rejchrt jaroslav Kvetina Viktor Vorisek Marcela Kopacova 2nd Department of Medicine Charles University in Praha Faculty of Medicine at Hradec Kralove University Teaching Hospital Institute of Clinical Microbiology Charles University in Praha Faculty of Medicine at Hradec Kralove University Teaching Hospital Institute of Experimental Biopharmaceutics Joint Research Centre of Czech Academy of Sciences and PRO.MED.CS Praha a.s. Institute of Clinical Biochemistry and Diagnostics Charles University in Praha Faculty of Medicine at Hradec Kralove University Teaching Hospital

Human intestinal microbiota create a complex polymi-crobial ecology. This is characterised by its high population density, wide diversity and complexity of interaction. Any dysbalance of this complex intestinal microbiome, both qualitative and quantitative, might have serious health consequence for a macro-organism, including small intestinal bacterial overgrowth syndrome (SIBO).SIBO is defined as an increase in the number and/or alteration in the type of bacteria in the upper gastro-intestinal tract. There are several endogenous defence mechanisms for preventing bacterial overgrowth: gastric acid secretion, intestinal motility, intact ileo-caecal valve, immunoglobulins within intestinal secretion and bacte-riostatic properties of pancreatic and biliary secretion. Aetiology of SIBO is usually complex, associated with disorders of protective antibacterial mechanisms (e.g. achlorhydria, pancreatic exocrine insuff iciency, immuno-deficiency syndromes), anatomical abnormalities (e.g. small intestinal obstruction, diverticula, f istulae, surgical blind loop, previous ileo-caecal resections) and/or motility disorders (e.g. scleroderma, autonomic neuropathy in diabetes mellitus, post-radiation enteropathy, small intestinal pseudo-obstruction). In some patients more than one factor may be involved. Symptoms related to SIBO are bloating, diarrhoea, malabsorption, weight loss and malnutrition. The gold standard for diagnosing SIBO is still microbial investigation of jejunal aspirates. Noninvasive hydrogen and methane breath tests are most commonly used for the diagnosis of SIBO using glucose or lactulose. Therapy for SIBO must be com-plex, addressing all causes, symptoms and complica-tions, and fully individualised. It should include treatment of the underlying disease, nutritional support and cyclical gastro-intestinal selective antibiotics. Prognosis is usually serious, determined mostly by the underlying disease that led to SIBO.

关键词： Bacterial overgrowth Breath test Hydrogen Methane Small intestine

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制备条件对稀土掺杂TiO_2物理性质和光催化降解吡唑草胺性能的影响（英文）

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催化学报 2015年第10期36卷 1679-1685页

作者： Marcela Kralova Irina Levchuk Vit Kasparek Mika Sillanpaa jaroslav Cihlar 布尔诺理工大学中欧科技学院拉普兰塔理工大学绿色化学实验室

多相光催化是一种非常有效的降解各种水污染物的方法.本文以稀土(镝和镨)掺杂的TiO2为光催化剂,考察了制备条件对其物理性质和光催化性能的影响.采用溶胶-凝胶法和不同条件(反应温度450,550,650 oC;反应时间4,8,12 h)的固态反应法制备了... 详细信息

多相光催化是一种非常有效的降解各种水污染物的方法.本文以稀土(镝和镨)掺杂的TiO2为光催化剂,考察了制备条件对其物理性质和光催化性能的影响.采用溶胶-凝胶法和不同条件(反应温度450,550,650 oC;反应时间4,8,12 h)的固态反应法制备了TiO2样品.运用X射线衍射分析了该样品的晶相,发现只存在锐钛矿相,并得到Raman光谱的证实.同时采用扫描电镜观察了样品的结构和粒径;以BET法计算了其比表面积;运用紫外-可见光漫反射光谱测得了样品的带隙能量.通过测量紫外光照射下常用除草剂吡唑草胺的降解速率评价了样品的光催化活性,反应过程中吡唑草胺的浓度用高效液相色谱分析.结果表明,稀土掺杂使得TiO2吸收边红移,并提高了其光催化活性;制备时最优的固态反应条件为550 oC反应8 h.

关键词：稀土掺杂二氧化钛镝镨合成条件光催化降解吡唑草胺

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