Search

Castor stalk is one of excellent woody materials.which is the byproduct of the castor oil plant. Itwas usually burnt without use at all when the castor seed were harvest. To use this resource, we studied the castor stalk based panel made with different resin including UF, PF and MDI resin. The results show that the properties of castor stalk based particle panel made with UF and MDI resin by certain techniques can reach the requirement of the standard of China expect the castor stalk based particle board with PF resin which will be studied further more.

Corn cobs are potential feedstock for producing heat, power, fuels, and chemicals. Densification of corn cobs into briquettes/pellets would improve their bulk handling, transportation, and storage properties. The objective of this study was to investigate the densification characteristics and specific energy requirements for the compression of corn cobs under four pressure levels (10, 12, 14, 16MPa) and with two particle size levels (2.41mm, 0.86mm). The compression behavior of ground corn cobs was studied using a hydraulic press briquetteing machine whose cylindrical die diameter was about 30 mm. The corn cobs moisture content and preheat temperature before compaction was 10% (w.b.) and 75 °C, respectively. The cylindrical die temperature was maintained at 90 ± 5 °C. It was found that the briquette density ranged from 809 to 1043 kg m-3; while the total specific energy requirement to compress and extrude briquette ranged from 17 to 26 MJ t-1, with an increase in pressure. Particle size had also a significant effect on briquette density and specific energy requirement. The finer corn cob grinds (0.86mm) resulted in higher density and lower specific energy requirement than the coarser corn cob grinds (2.41mm). New statistical models were developed to describe the total specific energy consumption of ground corn cobs during densification using a multiple linear regression analysis.

A graphene oxide/polyaniline composite was synthesized by an in situ polymerization process. This product was simply prepared in an ethylene glycol medium, using ammonium persulfate as oxidant in ice bath. The composite was characterized by field emission scanning electron microscopy, transmission electron microscopy, X-Ray photoelectron spectroscopy, Raman spectroscopy and electrochemical test. The composite material showed a good electrochemical performance.

SDBS modified graphene was prepared by electrochemical method using Sodium dodecylbenzenesulfonate (SDBS) as electrolyte and graphite rod as electrode. The anode graphite rod was corroded and deposited at the bottom of the electrolyte solution. The obtained graphene was characterized by Atomic force microscopy (AFM), Raman and Fourier transform infrared spectra (FT-IR). AFM images indicated that most of the layers had the thickness of less than 2 nm, suggesting the fromation of single layer of graphene. The resulting graphene showed very good dispersion stability both in water and in organic solvents (ethanol, acetone).

The solvent-based exfoliation of graphite, including into graphene and/or graphene-like platelets, is an important challenge. Here, we report a “direct” Friedel-Crafts acylation reaction between graphite and 4-ethylbenzoic acid (EBA) to afford edge-functionalized graphite (EFG). Unlike, for example, graphite oxide (GO), the functionalization is at the edges of the graphite and thus, the basal plane of individual layers in EFG is not functionalized. The EFG can be easily dispersed and exfoliated in common organic solvents to concentrations as high as 0.8 mg/mL. Large-are uniform films can be produced by solution-casting such dispersions on substrates and conductivities as high as 125 S/cm can be obtained by subsequent heat treatment at 900 °C under argon atmosphere. Hence, a few layers graphene obtained from annealing under argon atmosphere show the potential to replace Indium tin oxide (ITO).

In this work, we synthesized graphene nanosheets via a soft chemistry synthetic route involving pre-exfoliation treatment, strong oxidation, and post thermal exfoliation. X-ray diffraction (XRD), Raman spectroscopy, atomic force microscopy (AFM), and transmission electron microscopy (TEM) confirmed the ordered graphite crystal structure and morphology of graphene nanosheets. N2 adsorption was used to determine the specific surface area of graphene nanosheets. As a result, pre-treatment of the graphite with HNO3/H2SO4 mixture produced the exfoliated graphite nanoplates, and the post thermal exfoliation of the graphite oxide nanosheets at low temperature led to produce a large number graphene nanosheets. The specific surface area of obtained graphene nanosheets was 333 m2/g.

The aim is to treat oily sludge from floatation process of oil produced water by deflocculation. Based upon analyzing the granularity distribution and dewater efficiency of the flocs, floc breakage and dewater of oily sludge was carried out. The results indicated that the coagulant skeleton builder in sludge could be broken by changing the coalescent state, and deflocculation could disrupt skeleton of the floc and release interstitial water in sludge. The highest dewatering efficiency is about 81.2% at the pH of 4.5 by gravity sedimentation. The sludge had a broader range of granularity distribution and a smaller volume-average diameter. Moreover, the median diameter d (0.5) of the treated sludge was 36.0 μm, which was smaller than 73.1 μm of raw sample. Meanwhile, capillary suction time (CST) significantly decreased with pH adjustment. A wastewater removal efficiency of 90.99% for the treated sludge by pressure filtration could be achieved. The method would be a potential technique to be applied to other kinds of floatation sludge.

This study presents the experimental results of using admixture of used engine oil and kerosene as an alternative fuel in foundry shops. In this experiment, several proportions of used engine oil (well filtered) and kerosene were measured to make 1000ml per mixture using a calibrated beaker. Each mixture was fired in a furnacensuring atomization, ignition and combustion in a timed set up. Results of the experiment showed that admixtures of 100%, 95% and 90% volume of used engine oil gave low pour point hence were incombustible. 85%, 80% and 75% volume of used engine oil admixtures gave carburized flame. While 55% and below of used engine oil volume of admixtures gave oxygenated flame. 57% - 70% volume of used engine oil admixtures produced neutral flame which is ideal for melting. Of the latter proportions, 70% of used engine oil admixture had the highest heat content 70,780 kj/kg and the lowest cost. Hence this admixture is recommended as an effective admixture for fuel substitution in the foundry shop.

A moisture-measuring device for the determination of percentage moisture content of cassava particulate on dry basis during drying process was developed used to investigate the effect of pressure on the resistance of the cassava particulate sample. A thermo-gravimetric sample analysis was used for the calibration of the moisture measuring device. The device had four electrode cups, two of which were used as dummies to give a ½ Wheatstone bridge circuit used to measure the resistance. The resistance of the cassava samples increases with decrease in the %moisture content and decreases with increase in pressure.

The papers aim is to detail temper bead realization, as a possible solution to the removal of heat treatments. Applying temper beads could be a solution for repair, in case surface heat treatments are required, provided they are correctly applied. The paper presents the main ways of applying temper beads, presenting in the same time what the outcomes could be in case of not respecting the prescribed work sequence.

The objective of the paper is to present the newest results of our complex research work. In order to determination and comparison of the fatigue resistance, fatigue crack growth tests were performed on different grades of S690QL quenched and tempered, and S960TM thermomechanically rolled high strength steels.15 mmand30 mmthick base materials were used for our investigations. Welded joints were made from these base materials, using gas metal arc welding with matching, overmatching, and undermatching filler metals. In the paper, the performance of the welding experiments will be presented, especially with the difficulties of the filler material selection; along with the results of the fatigue crack growth examinations executed on the base materials and its welded joints. Statistical aspects were applied both for the presenting of the possible locations of the cracks in the base materials and the welded joints and for the processing of the measured data. Furthermore, the results will be compared with each other, and the possibility of derivation of fatigue crack propagation limit curves will be referred.

In the paper there are presented experimental results concerning mechanical characteristics of friction-welded joints in comparison with electron beam welded joints, made by 20VNiMoCr120 heat-resistant steel, which are part of some elements working at high pressure and temperature. The paper represents a study which suggests non-conventional welding and heat-treatment procedures for water and steam-supply pipes, large cylindrical recipients with high values of wall thickness, boiler pipes, steam turbines which compose thermo-energetic installations, in order to prevent failure appearance. The actual level of development in all activity fields proves the fact that on top of the performance and modernism, technological products and processes must assure a high reliability. All the results and experimental researches are obtained by the first author in her PhD Thesis.

In this paper there are presented results of research carried out for establishing the most favourable scenario of curing of the Polymer-Cement Concrete (PCC). The general recommendations for PCC point to the need of alternating conditions of curing of PCC. Polymer-cement concrete should be first cured in the wet conditions for effective hydration of Portland cement and then in air-dry conditions for polymer setting. According to the literature, the often accepted curing regime of PCC covers 5 days of wet curing and then the air-dry curing until the time of testing. According to the European Standards, the wet period should last 3 days. However, the authors` experiences show that the aforementioned scenarios is not the optimum one. The studies presented in this paper are the part of the larger research program, which – according to the authors` intention – should lead to the establishing of the optimum curing regime for PCC. The tests were carried out using two types of polymer modifiers: two-component epoxy resin and water dispersion of polyacrylates, introduced into the cement concrete mix. The following properties were accepted as the criteria of evaluation of PCC curing effectiveness: compressive strength, tensile splitting strength, surface tensile strength (by pull-off method), wear resistance, water penetration under pressure. These properties were evaluated after 28 days of curing according to the various regimes. The tests showed that the extension of the wet curing period beyond 5 days was favourable for the technical properties of PCC. The establishing of the optimum time of wet curing, however, needs further research. Also, some conclusions were formulated about the usefulness of the various properties as the criteria of PCC curing efficiency evaluation.

The paper presents results of the researches conducted upon the use of the arc-air gouging process with coated electrodes, in comparison with the plasma gouging process, in case of the welded structures. The paper aims at submitting the arc-air gouging technologies with electrodes and the plasma gouging technologies. The research consists in gouging a structural steel, of the quality S275JR and in comparing the surfaces obtained by the enumerated processes. The obtained samples will be analyzed in terms of microstructure, macrostructure, hardness of the thermally influenced area, hardness of the gouged area.The gouging process is based on melting the raw material, with an electric arc achieved between an electrode and the raw material; and on removing the melt material with a compressed-air jet, in the case of the arc-air gouging and plasma gouging. The gouging with coated electrode is different, given that it requires special electrodes, with thick flux cover, in order to generate an electric arc and a strong gas flux. During the gouging process, the raw material will be oxidized; yet, this does not influence the process. The gouging process can be either manual or automated. In this paper, the manual variant will be submitted, in the case of the arc-air gouging technology and the gouging with coated electrodes; in the case of the plasma gouging, both variants will be submitted.

The paper is focused on the use of advanced composite materials in the real application areas of buildings exposed to extreme environmental stress. The paper describe properties of composite rebar, especially with regards to long-term resistance to chemical and corrosion attack, minimization of heat transfer or resistance in construction with reduced concrete cover. The paper also presents behavior of composite rebar and concrete samples with composite reinforcement during loading and fire tests.

This paper refers to behaviour and capacity of axially loaded columns strengthened under load using welded steel plates. This method of strengthening is fast, simple and widely used but no universal and reliable analytical solution has been presented yet. In the paper, focus is put on flexural buckling. The approach using cross-section properties of strengthened member and the modified buckling reduction factor was used to calculate the ultimate resistance. In buckling theory, the resistance of column subjected to compression load is reached when the most stressed fibres start to yield. However, some researchers allow certain amount of yielding for base material of columns strengthened under load. In the paper, the new modified buckling reduction factor based on Eurocodes is derived. Two types of column strengthening under various preload magnitudes are investigated using finite element study in ANSYS code and transient analysis type. Birth and death of elements is used to simulate strengthening welded plates. The results are compared with analytical solutions.

The thermal cycles simulator of welding is a complex equipment that reproduces in a specimen thermal cycles of the type caused in the HAZ by welding processes.In this paper, it is presented a comparison between the results obtained by welded joints and thermal cycle simulator specimens, from the material P355NH of 22 mm thickness for pressure vessels. Two types of thermal cycle simulator specimens were used: one specimen without post-simulation heat treatment and one specimen with post-simulation heat treatment.For the welded specimens Mn3Ni1CrMo filler material was used.This paper offers information about the impact energy of specific areas of the welded joints, both for butt welding and thermal cycle simulator specimens.A good correlation was observed between the results of thermal cycle simulation with post-simulation heat treatment and the results obtained by welding.

The present paper shows the experimental results obtained on two complex alloys Co-Cr-W-C-Fe-Ni-Si-Mn-Mo and Ni-Cr-Fe-B-Si-C-Co alloys deposited on copper support by welding (TIG). Well - known for their excellent abrasive wear, corrosion and high temperature erosion resistance, these materials were chosen as protective solutions for some highly mechanically and thermally stressed devices, namely the blast tuyeres of blast furnaces. A testing method which simulates as near as possible the real working conditions is the quick thermal shock, consisting in heating at the chosen testing temperature followed by cooling in cool air spray, for 25 cycles. Testing parameters were set according to the blast tuyere device working conditions. In this paper, the coatings microstructure’s comparative changes consequently to quick thermal shock were monitoring, because this affect the device lifetime and mechanical characteristics. The untested samples as well as on quick thermal shocked ones was investigated using X-ray diffraction, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS).

Development of new steels with higher creep resistance must be based on detailed knowledge of strengthening and degradation processes, structural stability at high temperature exposure and their welding. This paper is concerned with the real weld joint hardness and microstructure of progressive low alloy creep resistance T24 steel. These steel is widely used in many power-plant constructions all over the Europe. Welding the T24 steels components is one of the most important technological procedures. The aim of the performed investigation is to evaluate the hardness and microstructure in the heat affected zone (HAZ) and the weld metal. Results of the secondary hardening in the real weld joints after low temperature post weld heat treatment (460°C/48h) and without post weld heat treatment at service temperature are described in this paper. Obtained results are compared to the hardness values of the weld joint post weld heat treated at recommended temperature (740°C). The microstructure of the real weld joints was analysed by transmission electron microscopy (TEM) in order to identify minority phases - MX nanoparticles and/or coarse (M23C6) particles. Secondary hardening of the not heat treated and low temperature heat treated T24 weld joint was proved.

This paper presents in detail the laser welding of a new mechatronic component belonging to the pressure sensors made ​​by aluminum alloy AW2007. Due to very high reflectivity of aluminum alloys, fast oxidation, the absorption of gases from the surrounding medium, special difficulties arise at laser beam welding and most situations require appropriate surface pretreatment. Given these issues, the paper present an experimental study on the influence of welding parameters on the seam quality for the aluminum alloy AW2007. In addition of the study regarding the influence of welding parameters, such as, laser power, welding speed, we conducted an analysis on the influence of the initial temperature of the material on the quality of the weld. Besides these aspects the paper presents a constructive solution for a device used to optimize the laser welding process of the sensor.

Nanotechnology has become a driving power in most of the branches of industry recently and construction industry is not an exception. Therefore, this paper deals with the topical problem of using nanoparticles in concrete. Carbon nanotubes (CNTs) with exceptional physico-mechanical properties were used in the experimental part of the paper. Their potential for enhancing characteristics of common concrete is promising. A frequent problem of application of carbon nanotubes is their agglomeration, which is caused by high surface tension, Van der Waals force and high ratio of sides. This fact limits possibilities of application of CNTs and it is the main reason of rare use of the promising potential of CNTs. Formed agglomerations can be dispersed by adding energy from outside and if suitable surface active agent in the solution of CNTs and water is added, their re-agglomeration can be prevented. Experimental part of the paper focuses on possibilities of dispersing CNTs by means of ultrasonic homogenizer Bandelin Sonopulse HD 3200 and suitable surface-active substance. Tests specimens were prepared from a suspension of water and CNTs with two different proportions and development of physico-mechanical properties in time was observed. Results confirmed the trends described in foreign literature sources and gave valuable impulses for further attempts to use nanotechnology in concrete technology.

Surface acoustic wave can be generated at the free surface of an elastic solid. Interdigital transducers (IDTs) are fabricated on the piezoelectric substrate surface that will act as electrical input and output port. When appropriate AC voltage stimulus is applied to the input transducer, surface acoustic wave will be produced. The output or receiving port will detect the incident surface acoustic wave and convert it back to a suitably filtered electrical once. For this property, surface acoustic based devices were initially developed for the telecommunication purpose such as signal filters and resonators. SAW based devices have been modified to be sensors later on from for gas detections and have been moving towards biological detections recently for its ultra-sensitivity to surface perturbation. The main component of this device is the IDTs. Recently, there are several methods to produce IDTs; Ultra-Violet (UV), deep UV lithography, Electron beam (e-beam) lithography and X-ray lithography. Although, these methods can produce very fine and accurate electrodes in term of submicron size but the costs are extremely expensive. Thus, this paper will discuss the conventional CMOS method which is much more economical to produce the applicable IDTs for the bacterial pathogens sensing purpose. Shear horizontal surface acoustic wave (SHSAW), one of the SAW based types is used in this paper as it is most suitable for the liquid based application as it has the advantage of acoustic energy is not being radiated into liquid.

It’s generally accepted that the transport of lithium ions in solid polymer electrolytes exists mainly in the amorphous regions, thus the research has focused on reducing the crystallinity to obtain high conductivity at room temperature. However, the point has been challenged: crystalline systems can provide a better ionic conductivity. In this paper, PEO/LiClO4polymer electrolytes with different lithium-oxygen ratios were prepared by melt-blending. The results show that [EO]/ [Li+] = 3 system has higher ionic conductivity, 4.26×10-6S/cm, more than twice as that of [EO]/ [Li+] = 4 system. DSC and XRD results show PEO3:LiClO4crystalline phase present in both systems, the crystallinity of [EO]/ [Li+] = 3 system is higher. It illustrates the generally accepted mechanism is not suitable for these systems, suggesting the high conductivity of [EO]/ [Li+] = 3 system is due to the unique crystal structure of PEO3:LiClO4. Besides, as the crystallinity increases, the tensile strength of [EO]/ [Li+] = 3 system increases greatly, to 1.43 MPa. In addition, because of the high melt temperature of PEO3:LiClO4, the electrolytes will gain excellent heat resistance. In summary, this paper provides a new idea to prepare polymer electrolytes with high ionic conductivity, improved strength and excellent heat resistance in large scale.

Copper alloys with high strength and high conductivity are a serial of materials with excellent comprehensive performance. However, the strength and the conductivity are a pair of conflicting factors. To resolve this contradiction, Cu-1.0Cr-0.12Zr alloy was studied in this paper. With optical microscope, scanning electron microscope, Brinell hardness and the arms bridge, effects of heat treatment on microstructure and properties of such alloys was studied,and we strived to find a heat treatment processing to achieve the best match between the conductivity and the strength of the alloy. This paper focused on the study of conductive properties of the alloy. The main factor infuencing the conductivity of the alloy was the content of the soluting elements. The higher the content,the lower the conductivity, and vice versa. The results showed that the best comprehensive properties were obtained after solid solution at 920°C and then aging at 450°C for 180 min.

The pull-in behavior of carbon nanotubes (CNTs), which is the sudden increase in the deflection of two interacting CNTs, affects the properties of CNT networks significantly, and thus becomes an important subject in applications. In this paper, an energy-based analysis is carried out to predict the pull-in behavior as well as the critical pull-in distance between two interacting CNTs, and the results agree well with the subsequent atomistic simulations. Furthermore, the factors that affect the critical pull-in distance are also investigated. It is found that the length and diameter of CNTs and space angle between CNTs affect the critical pull-in distance significantly: the critical pull-in distance increases almost linearly with the increasing CNT length and decreasing CNT diameter, and the parallel CNTs have a much higher critical pull-in distance than the non-parallel CNTs. Besides, the chirality of CNTs has a little influence, and when the two CNTs are both zigzag and armchair, the critical pull-in distance is higher than the CNTs with other chiralities due to their stronger commensurability effect. The method and results in this paper will provide nanoscale reference for the design and optimization of CNT-based nanomaterials and nanodevices.

Concrete mechanical properties under dynamic load such as blast and impact are very complex. Shock wave propagation law and damage effect in the concrete were studied numerically in the paper by using TNT explosive ignition and growth model, concrete dynamic damage model, and SPH method. And shock wave properties of different mass explosives in the concrete were analyzed with the similarity theory. The result shows that TNT shock wave propagation law meets the internal-blast similarity law. Peak pressure, positive pressure impulse, maximum velocity and maximum acceleration in the concrete decrease with the increase of scaled distance. And time needed for reaching peak pressure increases linearly with the increase of scaled distance. A theoretical basis of structure and protection design for constructions is achieved in the paper.

The microwave differential thermal analysis (MW-DTA) is a new procedure to evaluate the materials, barium ferrite type M in this paper, according to the phenomena appeared during the material heating. The paper presents a new evaluation technique which is faster and with low energy consumption. The microwaves are used to heat the material, two infrared pyrometers for monitoring the temperatures on the material surface and a temperature regulator where the data are recorded for evaluation. The material, a homogeneous mixture of Fe2O3+BaCO3, is a ceramic material with good absorbance properties, so the heating will be pure microwave heating. The results and the DTA graphic is automatically generated by the temperature recording device based on the data sensed by the infrared pyrometers. The paper presents technical aspect regarding to the microwave heating and temperature measurement in microwave field and how to make differential thermal analysis in microwave field.

A variety of current scientific work shows the importance and possibilities of an effective conditioning of tribological contacts to minimize friction and wear, respectively an increase in performance of tribological highly stressed components. By slight modifications of the finishing process positive effects like the increase of lifetime or increase of power can therefore be generated. Based on this approach the tribological system piston ring/cylinder running surface of internal combustion engines is an example with high potential for optimization of production. This paper introduces alternative production and conditioning processes. The evaluation of chemical modifications of boundary layers, which are used in addition to the topography as a representative indicator for the description of the functionalities of produced surfaces is considered to be a special aspect. The present paper combines considerations of manufacturing technology with tribological tests showing the relationships and dependencies between the process characteristics of finishing and the operational behavior of the examined components.

Numerical simulations are powerful tool for analyzing and research in domain of mechanical constructions. In welded joints is very important to determine residual stresses and temperature distribution in sample, apropos, element of construction. In some cases doing the experiment is not possible, so numerical simulations can give the required results and overview of stress state, residual stresses, critical areas, displacement, temperature distribution and other data is needed for analyzing and improvement of constructions or parts of constructions. This analysis includes finite element model for the thermal and mechanical welding simulation. Welding simulation was considered as a sequential coupled thermo-mechanical analysis. The residual stress distribution and magnitude in axial direction was obtained. The paper also shows the results obtained in a simultaneously test of a butt welded thin steel sheet specimen by conventional methods and thermography. Numerical methods are also used in order to predict the crack of specimen. The obtained results confirm that it is very useful to use thermography and Finite Element Method (FEM) for early diagnostics of the complex structures in the exploitation conditions. In this paper is obtained good agreement of results between experiment and Numerical simulations.

This paper introduces results of fracture experiments on fine-grain concrete specimens prepared from CEM 42.5 R Portland cement of different origin (five Czech Republic localities: Mokrá, Hranice, Radotín, Prachovice, Čížkovice), with natural zeolite admixture. Although the specimens were produced using the same type of cement, this paper shows that even small differences in chemical and mineralogical composition (caused by different origin) can result in changes of mechanical fracture parameter values.

The paper aims to explore influence of elements of transition metal (TM) and rare earth (RE) on iron-carbon micro-electrolysis for dyeing effluent degradation. There is evidence that there aren't many reports about it in domestic literature. The paper analysed the morphologies of surfaces of irons and activated carbons and designed the orthogonal experiments. Next was discussion for related influence factors. It deduced the mechanism that TMs and REs assist zero-valent iron (Fe0) catalysing degradation of dyeing effluent. It is based on following explanation. Cations of manganese and cobalt easily penetrate Fe0 lattices, but doesn't Ce4+ because of larger radius. Thus Ce4+ is weaker than Mn2+ and Co2+ for improving Fe0 activity. Furthermore, because the valence electron structure of Mn2+ is more stable than that of Co2+, Mn2+ is more efficient to assist Fe0 degrading dyeing effluent than Co2+. Therefore, the ranking of affecting Fe0 activity from greatest to smallest is Mn2+, Co2+ and Ce4+.

The welding process causes transient thermal stresses and non-continuous plastic strains around the weld due to the induced high temperatures. Uneven heating and cooling during the welding process cause a residual stresses in the welded member. The paper deals with the local influence of welding process and its global consequences at the creation and final redistribution of welding stresses. The paper also presents a verification of Modified empirical formulae, developed by the author, using experimental results of research program oriented to the effects of welding stresses and beams local stability [1, 2 and 3].

Wind turbine blades are the major structural element and highest cost component in the wind power system. Modern wind turbine blade sizes are increasing, and the driving motivation behind this is to increase the efficiency and energy output per unit rotor area, and to reduce the cost per kilowatt hour. However due to the increase in size the material selection for wind turbine has become critical and complex. To achieve the desired materials to improve the design of wind turbine blades several factors such as high fatigue strength, less weight, less cost and potential of recycling must be focused. Basalt fiber is a relative newcomer to fiber reinforced polymers and structural composites. Basalt fiber with their excellent mechanical properties represents an interesting alternative composite material for modern wind turbine blades. Some manufacturers claim that basalt fiber has similar or better properties than S-2 glass fiber and its cheaper than carbon fiber. Basalt fiber together with carbon fiber are the most advanced and interesting area of hybrid technologies. This paper reviews extra ordinary properties of basalt fiber over other fiber reinforced composites and highlight how the basalt special properties together with carbon fiber will reduce the weight and cost of wind turbine blades while improving their performance. This paper also demonstrates why the basalt carbon hybrid composite material will be an ideal alternative for the wind turbine rotor blades.

This paper mainly introduces the mechanism of microwave heating: electric conduction loss, eddy current loss and arc discharge. The microwave heating behavior of 316 stainless steel powder body which made by gel casting was investigated in the paper. Experiments on different microwave power, powder particle size, and the content of auxiliary heating material showed that the smaller the powder particle size, the larger microwave power and auxiliary heating materials help 316 stainless steel body for sintering.

Microbending optical fiber pressure sensor is designed with the sensing unit based on multimode fiber in this paper. It consists of the pressure gasket, the microbending regulator and the metal clamp with fine adjustment structure. The measuring range of the sensor could be adjusted by choosing different gasket. When pressure acts on the fixture, a little displacement may occur, and luminous flux of the fiber will be lost after going through microbending part. According to the principle of light field detection, the pressure measurement can be achieved by detecting the loss of light intensity caused by different load. The basic structure of the sensor and its sensing mechanism are well introduced in this paper. In addition, for improving the effectiveness of the Microbending optical fiber pressure sensors, we set up mechanical zero adjustment and the maximal displacement limitation in order to avoid sensor breakdown caused by excess displacement.

As the needs of optical glasses are on the rise, the precision on shape, form, surface qualities and the scaling down of sizes are rising, too. The standards and surface finish of reference mirrors used in measuring appliances are crucial; hence, enhancement of the surface finish is indispensable in manufacturing industries. This paper proposes a self-propelled multi jet polishing technique for ultra precision polishing process in which bladelessTesla turbinewas used as a prime mover. The turbine is characterized by high swirling velocity at the outlet; therefore, high kinetic energy in the course of away from the turbine was used as polishing energy. Simulation of the flow of the field of turbine blades using computational fluid dynamics software (CFD) has also been presented. With a newly designed and manufactured polishing tool, this paper investigates the optimal polishing parameters for surface roughness improvement of crown optical glasses using Taguchis experimental approach; signal-to-nose (S/N) ratio and ANOVA analysis was also carried out to determine the effect of main factors on the surface roughness. Consequently, a 2.5μm size of Al2O3abrasive, 10wt% abrasive concentration, 80rpm of polishing head, 6 numbers of nozzles, 6 kg/cm2of pressure, and 45min. of polishing time have been found to be the optimal parameters. It was observed that about 94.44% improvements on surface roughness; Ra, from 0.360μm to 0.020μm has been achieved using the optimal parameters. In addition to this; angular speed of polishing head, pressure and polishing time were found to have significant effect on surface roughness improvement.

In paper are presented information about materials used for production of models by Fused Deposition Modeling (FDM) rapid prototyping technology. In today's rapid prototyping technologies the initial state of building material can be in solid, liquid or powder state. The current range materials include plastic, nylon, wax, resins, metals and ceramics. In FDM are mainly used as basic materials ABS - Acrylonitrile Butadiene Styrene, polyamide, polycarbonate, polyethylene and polypropylene. Main part of the paper is focused on experimental testing of Acrylonitrile Butadiene Styrene materials realized by different research teams and presents outputs of testing of ABS material in FDM technology realized by authors.

The influence of impact toughness in vanadium-bearing high strength weathering steels CGHAZ was researched by welding thermal simulation in this paper. The melting and precipitation situation of V, Ti and N in the high strength weathering steel was analyzed in the process of welding thermal simulation according to relative papers. According to the research, TiN in the steel plays a decisive role in CGHAZ on its impact toughness, and give a suggestion about the content of Ti in order to promote the tested steels impact toughness in CGHAZ.

The paper is concerned on the properties of the new ideal circuit element, a memristor. We proposed memristor with nanothin three layers of Pt/ TiO2-x/TiO2/TiO2+x/Pt sandwiched structure in this paper,based on study of the working principles of HP memristor. As the new TiO2+xlayer and its expansion effect,the switching speed of the new structure memristor mentioned would be faster. The paper gives the test result and mechanism of the new structure memristor, such as characteristic analysis results of Pt nanowire, memristor, repetitiveness and V-I characteristic hysteretic curve of three layers memristor by using semiconductor tester.

Recent developments in the growth of InGaN layers made it possible to grow a heavily doped p-type layer with Indium concentration up to 40%. In this work, a tunnel junction based on these developments has been designed with the use of Silvaco TCAD. This diode introduces a low resistive path to the current carriers, effectively adds voltages and encounters the parasitic effects of the stacked sub-cells. A double-junction solar cell is designed based on our interfacing tunnel diode and simulated results are presented in this paper. Remarkable results are achieved comparing to the existing InGaN based multijunction solar cells. A highVocof ~3.1V and conversion efficiency greater than 17.5% has been achieved under AM 1.5. This paper also highlights and discusses the challenges in fabrication of such a highly efficient solar cell.

This paper presents results of laboratory investigation microstructure bearing steel 100CrMnSi6-4 after laser hardening in the air and cryogenic environment. Usied high-power laser CO2 (4 kW) were selected the best parameters for hardening process (power density, scanning speed, the overlap surface hardened zones). As a result, laser hardening of the surface layer steel 100CrMnSi6-4 with selected process parameters obtained highdispersing martensitic microstructure of microhardness to 900HV0.1 with isolated fragmented chromium carbides. In the heat affected zone found martensitic- bainitic and bainite microstructure. In comparison with conventional hardening (e.g. inductive) were significant microstructure fragmentation and increase hardness about 15%. This paper presents ablative laser texturing surface layer above steel hardened before by laser. Texturing process was carried out in two environments and used pulsed iterbium fiber laser radiation Nd: YAG with a wavelength λ = 1064 nm.

In this paper, generation and harm of SO2are described. Cansolv SO2Scrubbing, a regenerated amine process, is mainly described with respects to its process principle, features and application. This paper analyzed the existing problems such as corrosion , crystallization and loss of amine. Prevention measures were proposed according to the monitoring data, analysis and research.

Based on the heat-resistant mechanism, the orthogonal experimental method and the requirements for physical-mechanical performances of heat-resistant concrete, one mixing process project was taken as the target for analysis on the mixture ratio design of heat-resistant concrete. The conventional raw materials such as normal Portland cement, common crushed aggregates, fly ash and concrete admixture were adopted to manufacture the C30 heat-resistant concrete which gets the limit heat-resistant temperature of 500°C subsequently. And the influencing factors on the strength of heat-resistant concrete were also studied in this paper. Experimental results show that the mixture ratio design of heat-resistant concrete in this paper is reasonable. The engineering application results also show it is financially viable that adopting the normal Portland cement to manufacture the heat-resistant concrete with limit heat-resistant temperature of 500°C.

The influence of crystallization conditions of leaded tin bronze on the obtained microstructure parameters is examined in the paper. Modification of crystallization conditions was realised by varying the cooling rate of the melt with preheating of the casting molds. Quantitative regularities of the influence of the cooling rate of bronze on its phase composition are presented. Data on mechanical properties of the material under investigation are also reported in the paper. It is demonstrated that high cooling rates (casting into mold at ambient temperature) enable obtaining higher mechanical properties in comparison with low cooling rates (casting into mold heated up to 800 °С).

In this paper, through understanding, analyzing and comparing of domestic and foreign treatment of high concentration organic wastewater, then derived organic wastewater can be economical and efficient handled by micro-electrolysis. But at the same time, the traditional micro-electrolysis also has some disadvantages. This paper discusses a new micro-electrolysis technology, namely cavitation-impinging stream electrolysis technology which has the advantages in treating high concentration organic wastewater. It is not only solving the process of passivation and harden problems in high concentration organic wastewater by traditional micro-electrolysis technology, but also combining with the characteristics of impinging stream coupled cavitation enhancement more effectively, making the degradation of organic pollutants maximize.

ZnO in various nanostructures forms have been widely studied for the application such as in solar cells, light emitting diodes, UV sensors and so on. In this paper, we have successfully deposited ZnO nanotetrapods using thermal chemical vapour deposition (TCVD) technique on layer-by-layer ZnO seeded catalyst, with Zn powder and O2 gas as source materials. We demonstrate that by using double furnace TCVD system, ZnO nanotetrapods can be deposited at lower temperature than the vapour temperature of the Zn powder. In this paper we report the effect of different deposition temperature (450 °C to 600 °C) on the surface morphologies, crystalline structure and optical properties of the ZnO nanotetrapods. FE-SEM micrographs show that the length of the nanotetrapods arms decreases with the increase of the deposition temperature. PL spectra show that the visible emission are very low compared to the UV emission which indicates that the ZnO tetrapod have very low intrinsic defect. The highest UV emission intensity is given by the sample deposited at 500 °C.

This paper presents a numerical model of rubber composite using a COMSOL multiphysics program to simulate electrical properties of the rubber composite in the frequency range of 300 kHz to 30 MHz. The rubber composite was made of natural rubber vulcanized with carbon black and carbon nanotube. The chracterization was done by setting up a parallel plate capacitive structure in a shape of circular disk with a diameter of 38 mm and using the RF vector network analyzer to measure electrical properties in term of electrical impedance, specifically resistance (R) and reactance (X). Three different thinknesses of rubber composite sheets were used in the experiment, specifically 0.7 mm, 1.7 mm, and 2.9 mm. From the physical dimension of the test setup, capacitance (C), dissipation factor (D), relative permitivity (εr), and conductivity (σ) can be calculated. These extracted parameters together with the physical dimension of the test structure were used to create COMSOL multiphysics simulation models. The program can simulate non-linear modeling of the rubber composite under different electromagnetic constrains. The simulation results were compared to the measured results for all samples. Comparison results show that all electrical parameters were closly matched, indicating that the COMSOL multiphysics models were correctly generated. The results also indicate that the conductivity and the relative permittivity of the tested rubber composite change dramatically at the frequency above 10 MHz. The results indicate the physical limit of the tested rubber composite in the sensing application. The simulation model proposed in this paper can be used to design and possibly predict the geometical and electrical properties of the rubber composite in future applications.

This paper proposes a method based on the spectra response of IR detectors mounted on thermographic camera for emissivity measurement at various target surface temperatures, while the reflected temperature istaken into account, and also studies on the effect of surface roughness on the emissivity value. The emissivity (ε8-14μm) of general engineering material such as iron, stainless steel, brass, copper and aluminum obtained in this paper are in agreement with other literatures. Finally, results found that the roughness and emissivity of equipment increases with increasing of the operating time.

The paper presents advanced ultrasonic and eddy current NDE techniques developed in the authors laboratory for nondestructive evaluation of austenitic stainless steel welds. The paper discusses the performance and comparison of 2D discrete wavelet transform (DWT) and de-noising methods applied on eddy current images obtained from stainless steel weld pad with machined longitudinal notches and a systematic approach for eddy current defect characterisation in weld pads by neural network. The simulation and experimental results on the effect of elastic anisotropy on ultrasonic phased array inspection in austenitic stainless steel weld are also discussed. A guided wave based ultrasonic method developed for detection of defects in stainless steel welds and its validation with complimentary techniques such as radiography and in-situ metallography are also presented.

In view of using only the intensity information of retroreflection light and poor capacity of anti-interference in laser short-range detection, this paper presents a short-range detection method based on laser polarization properties of targets, designs the polarization detection model and constructs the polarization detection system. Through the analysis and the comparison of data which is obtained from the polarization characteristic and intensity characteristic experiments of five different targets, the conclusion that the detection method based on the laser polarization characteristics can effectively distinguish target is achieved. Meanwhile, the analysis of detection model in this paper can also provide certain theory significance for further research on polarization detection.