Lime-Barium and Lime-Zinc Raw Glazes with Raw Materials from Tanzania and Cameroon

In the paper, the lime-barium and lime-zinc glazes used in Southern and Eastern Africa Mineral Center (SEAMIC) ceramic unit in Tanzania were investigated for the production of high temperature raw glazes in Cameroon. The base Seger formula used was 0.3KNaO, 0.3CaO, 0.4ZnO or BaO;xAl2O3 and ySiO2. Different Al2O3/SiO2 formula ratios for glossy and matt glazes were tested with raw materials from Cameroon and Tanzania. In the Cameroonian glazes, a local pegmatite (quartz, microcline, albite) with low coloured oxides replaced an albitic feldspar in the Tanzanian glazes. The other materials were kaolin, limestone, silica and barium carbonate or zinc oxide. The glazes were tested at Seger Cone 7 (1240℃) on stoneware slabs (made up of the same feldspathic glaze material: 18%, silica sand or quartz 27%, ball clay 40% and kaolin 15%) from both Tanzania and Cameroon materials. From results obtained, zinc oxide acted as a more vigorous flux than barium carbonate at cone 7, which is obvious in the glazes with pegmatite (with high quartz content). At a Seger formula of Al2O3/SiO21:10, transparent glazes were obtained. In these glazes the alumina content was lower and when increased to higher Seger ratios 1:4.7 - 8.7, the gloss was lowered to matt-luster due to fine crystal formation.

Creating Matte and Opaque Stable Colored Glazes on Local Omani Earthenware Pottery: Testing White Zircon Borax Frit Glaze Recipes

The ability of Omani local pottery earthenware to accept low- and medium-temperature fired glazes can face technical difficulties. The impurities included in the clays extracted from local fields, especially iron oxide, are a noted weakness that affects painting the local pottery with shiny, opaque, or matte glazes. Previously published research conducted by the researcher on Omani earthenware clays focused on finding a special transparent, shiny, and stable glazing recipe, but few studies have provided matte and opaque glazing recipes that are technically suitable for local Omani clays. By using laboratory-based experimental methodology, this research will investigate the possibility of using White Zircon Borax Frit (WZBF) to develop matte and opaque stable glazes that are suitable with local Omani pottery clay bodies. In the end of this experimental research, the purpose of this project is to develop applicable glazing recipes to be used for painting pots made by Omani clays.

A Study of Ca-Mg Silicate Crystalline Glazes——An Analysis on Forms of Crystals

In the study on Ca-Mg silicate crystalline glazes, we found some disequilibrated crystallization phenomena, such as non-crystallographic small angle forking and spheroidal growth, parasitism and wedging-form of crystals, dendritic growth, secondary nucleation, etc. Those phenomena possibly resulted from two factors: (1) partial temperature gradient, which is caused by heat asymmetry in the electrical resistance furnace, when crystals crystalize from silicate melt; (2) constitutional supercooling near the surface of crystals. The disparity of disequilibrated crystallization phenomena in different main crystalline phases causes various morphological features of the crystal aggregates. At the same time, disequilibrated crystallization causes great stress retained in the crystals, which results in cracks in glazes when the temperature drops. According to the results, the authors analyzed those phenomena and displayed correlative figures and data.

The Impact of Sun Radiation on the Thermal Comfort in Highly Glazed Buildings Equipped with Floor Heating Systems

Occupants of highly glazed buildings often suffer from thermal discomfort during the mid-seasons when no shadings are used in such buildings,especially when inertial heating systems are used.The present study is devoted to evaluating the impact of long solar beam exposure on the internal thermal discomfort in glazed spaces when heating is implemented through a floor system.A comprehensive experimental study is carried out using an experimental bi-climatic chamber which is fully monitored and controlled,allowing realistic simulations of the dynamic movement of the sun patch on a heated slab.The findings show that a period of discomfort as long as 8 h can occur,and persist far after the sunbeam exposure stops.During this period,the heating slab’s surface temperature,considered from an average point of view,can attain 34°C while the indoor temperature reaches 26°C.Simulations conducted using a previously developed model display a good fit with the measurements.

Designing interactive glazing through an engineering psychology approach:Six augmented reality scenarios that envision future car human-machine interface

Background With an increasing number of vehicles becoming autonomous,intelligent,and connected,paying attention to the future usage of car human-machine interface with these vehicles should become more relevant.Several studies have addressed car HMI but were less attentive to designing and implementing interactive glazing for every day(autonomous)driving contexts.Methods Reflecting on the literature,we describe an engineering psychology practice and the design of six novel future user scenarios,which envision the application of a specific set of augmented reality(AR)support user interactions.Additionally,we conduct evaluations on specific scenarios and experiential prototypes,which reveal that these AR scenarios aid the target user groups in experiencing a new type of interaction.The overall evaluation is positive with valuable assessment results and suggestions.Conclusions This study can interest applied psychology educators who aspire to teach how AR can be operationalized in a human-centered design process to students with minimal pre-existing expertise or minimal scientific knowledge in engineering psychology.

An Advanced Control Technology Robotic Casting and Glazing for Ceramic Bowls

Glazes on ceramics provide a durable finish as well as a protective layer, impervious, sanitary, and generally easily cleaned surface, have the advantage of having a very wide spectrum of colors. As a result, color has a lot of variability, luminosity and permanence. This method of coating is suitable for products that are not too big a smooth and can be done quickly such as plating of coffee mugs, cups or bowls. Putting the product in the enameled tank must not be soaked for too long as it will thicken the coating. When the coating is dry it will slip off easily. Therefore, this research is to provide product dipping. Good and consistent plating at all times and then industrial robots are used to help in plating or dipping. The robot can control the work quickly. According to the position and speed control can reduce the working time in the further.

The effect of single-horn glaze ice on the vortex structures in the wake of a horizontal axis wind turbine

The present study experimentally investigated the effect of a simulated single-horn glaze ice accreted on ro- tor blades on the vortex structures in the wake of a hori- zontal axis wind turbine by using the stereoscopic particle image velocimetry （Stereo-PIV） technique. During the ex- periments, four horizontal axis wind turbine models were tested, and both ＂free-run＂ and ＂phase-locked＂ Stereo-PIV measurements were carried out. Based on the ＂free-run＂ measurements, it was found that because of the simulated single-horn glaze ice, the shape, vorticity, and trajectory of tip vortices were changed significantly, and less kinetic en- ergy of the airflow could be harvested by the wind turbine. In addition, the ＂phase-locked＂ results indicated that the pres- ence of simulated single-horn glaze ice resulted in a dramatic reduction of the vorticity peak of the tip vortices. Moreover, as the length of the glaze ice increased, both root and tip vortex gaps were found to increase accordingly.

Investigation on surface figuration and microstructure of laser glazed nanostructure zirconia thermal barrier coatings

CO2 continuous wave laser beam had been applied to the laser glazing of plasma sprayed nanostructure zirconia thermal barrier coatings. The effects of laser glazing processing parameters on the surface figuration and microstructure change had been carried out, the microstructure and phase composition of the coatings had been evaluated by the scanning electron microscope （ SEM） and the X-ray diffraction （ XRD ）. SEM observation indicates that the microstructure of the as-glazed coating could be altered from singlecolumnar structure to a combination of the columnar grain and fine equiaxed grain with the different laser glazing conditions. XRD analysis illustrates that the predominance phase of the us-glazed coating is the metastable tetragonal phase, and the glazed coating with the single columnar structure has shown the clear orientation in （220） and （400） peaks while the other coatings do not show that.

Dynamic performance of cable net facade with consideration of glass panels under earthquake

Shaking table tests and theoretical analysis were conducted to study the dynamic performance of cable net facade with consideration of glass panels under earthquake. Firstly,the dynamic response of cable net faade under earthquake was investigated with shaking table test. Then the working mechanism of glass panels in coordination with cable net was proposed. Accordingly,a numerical simulation model of glass panel's working in coordination with cable net was built for the dynamic analysis.And then the seismic response was analyzed with this model theoretically. The study indicates that the seismic response of the cable net with glass panels on most occasions is mainly decided by the symmetric modes,and the first vibration mode is dominant. The damping of cable net facade is mainly decided by glass panels. And it is very good for cable net faade to restrain its dynamic response under earthquake.

Numerical Study on Ridge Ice Accretion and Its Effect Under Thermal Ice Protection

Under the condition of thermal anti-icing,the liquid water on the leading edge of the airfoil that would flow to the downstream non-protective zone will produce ridge ice,thus endangering flight safety.Based on the existing three-dimensional(3 D)icing model which considers the water film flow on the ice layer,an icing model with thermal boundary condition is introduced.With the boundary conditions of none anti-icing and thermal anti-icing,glaze ice accretion and ridge ice accretion are simulated on a simplified airfoil of unmanned aerial vehicle(UAV),and then the lift coefficient and drag coefficient are calculated and compared with the smooth airfoil under the same conditions.The results show that the lift-drag ratio obviously decreases after glaze ice occurred on the leading edge under the condition of none anti-icing;and that after setting the condition of anti-icing heat flux in the impingement area,the glaze ice on the leading edge becomes thinner and the ridge ice occurs in the non-protective zone,so the airfoil with this icing characteristic gets a lower lift-drag ratio.

Numerical Simulation of Icing on Nrel 5-MW Reference Offshore Wind Turbine Blades Under Different Icing Conditions

Offshore wind energy resources are operational in cold regions,while offshore wind turbines will face the threat of icing.Therefore,it is necessary to study icing of offshore wind turbines under different icing conditions.In this study,icing sensitivity of offshore wind turbine blades are performed using a combination of FLUENT and FENSAP-ICE software,and the effects of liquid water content(LWC),medium volume diameter(MVD),wind speed and air temperature on blade icing shape are analyzed by two types of ice,namely rime ice and glaze ice.The results show that the increase of LWC and MVD will increase the amount of ice that forms on the blade surface for either glaze ice or rime ice,and an increase of MVD will expand the adhesion surface between ice and blade.Before reaching the rated wind speed of 11.4 m/s,it does not directly affect the icing shape.However,after reaching the rated wind speed,the attack angle of the incoming flow decreases obviously,and the amount of ice increases markedly.When the ambient air temperature meets the icing conditions of glaze ice(i.e.,−5℃ to 0℃),the lower the temperature,the more glaze ice freezes,whereas air temperature has no impact on the icing of rime ice.Compared with onshore wind turbines,offshore wind turbines might face extreme meteorological conditions,and the wind speed has no impact on the amount of ice that forms on the blade surface for most wind speeds.

Preparation of Lead-free Base Glaze Suitable for Pearlescent Pigments by Low-temperature Solid-phase Reaction with Alkali Waste

A lead-free base glaze suitable for pearlescent pigments was prepared by a low-temperature solid-phase reaction with alkali waste.Tests were performed to evaluate the effects of the sintering conditions and alkali waste composition on the prepared base glaze and pearlescent glaze.The experimental results show that partially replacing SiO_(2) with B_(2)O_(3) effectively reduced the sintering temperature and time to form a glass network,but the network structure becomes disconnected as the B_(2)O_(3) content increases.An amorphous base glaze was obtained when soda ash was replaced with a small amount of alkali waste,but increasing the addition of NaCl further was adverse to base glaze formation by resulting in crystallization of the base glaze and a decrease in the bridging oxygen content.The pearlescent pigment was thermally stable in the glaze at 750℃,while higher temperatures caused the crystalline phase of NaAlSiO_(4) to appear and adhere to the surface of pigment granules,which degraded the pearlescent effect of the glaze.

A Novel Infrared Radiant Glaze Exhibiting Antibacterial and Antifungal Functions

Infrared radiant powder was synthesized by conventional ceramic processing techniques by using Fe2 O3, MnO2, CuO, Co2 O3 and kaolin as raw materials. A novel infrared radant glaze was developed by introducing the infrared radiant powder into glazing as a functional additive. Infrared radiant characteristics of the powder and the glaze were investigated. The optimum content of infrared radiant powder in glazing was ascertained to be 5% . The infrared radiant glaze exhibits significant antibacterial and antifungal Junctions due to the thermal effect of infrared radiation. Antibacterial percentages of the glaze reach 91% - 100% when Escherichia coli, Staphylococcus aureus and Bacillus subtilis are used as model bacterium respectively, while antifungal percentage of the glaze exceeds 95% when Penicillum citrinum is used as model fungus.

LASER GLAZING OF Ni-Nb AND Ni-Nb-Cr ALLOYS AND CORROSION RESISTANCE OF AMORPHOUS LAYERS

Partially amorphous Ni-Nb alloy was made by 1.91 kW cw CO_2 laser melt-quenching, and fully amorphous by 4.5 kW and 4.9 kW.The corrosion resistance of the amor- phous layer was improved by adding Cr.Potentiodynamic polarization curves show that the amorphous Ni_(50)Nb_(40)Cr_(10) is in more corrosion-resistant than the amorphous Ni_(60)Nb_(40)and 18-8 stainless steel.

Effect of Fly Ash on Drying Shrinkage of Thermal Insulation Mortar with Glazed Hollow Beads

Drying shrinkage of thermal insulation mortar with glazed hollow beads was measured by a vertical length comparator, and the influences of fly ash with different contents（0, 18%, 36%, and 54% were used） on the long-term drying shrinkage were discussed. The mass loss was measured by the weighting method and the pore structure was characterized using three different methods, including the light microscopy, the mercury intrusion porosimetry（MIP）, and the nitrogen adsorption/desorption（NAD） experiments, and the correlations among them were researched. The results show that drying shrinkage process of thermal insulation mortar includes three steps with increasing curing time： the acceleration period（before 7 d）, the deceleration period（7-365 d）, and the metastable period（after 365 d）. Drying shrinkage in the first stage（7 d before） increases quickly owing to the fast water loss, and its development in the last two stages is attributed to the increment of the pore volume of mortar with the radius below 50 nm, especially the increment of the pore volume fraction of the pore radius within the size range between 7.3 nm and 12.3 nm. There is no change in the drying shrinkage development trend of mortar with fly ash addition, and three steps in the service life, but fly ash addition in the mortar restrains its value. There is a linear relationship between the drying shrinkage and fly ash content, which means that drying shrinkage reduces with fly ash addition.

Application of cetylpyridinium chloride in dispersion of antibacterial ceramic glaze

The adsorption of cetylpyridinium chloride(CPC)onto a ceramic glaze mixture composed of limestone,feldspar,quartz,kaolin,and antibacterial agent was studied.Both adsorption isothermals and the average particle zeta potential were investigated in order to understand the suspension stability as a function of pH,ionic strength,and surfactant concentration.The results show that under the optimal conditions such as pH value of 7 or 9,0.01 mol/L of ionic strength and around critical micelle concentration(CMC)of surfactant,antibacterial ceramic glaze acquires fine dispersion stability.The adsorption of CPC on ceramic glaze particles is in accordance with Langmuir model in 0.01mol/L at pH=7 and pH=9.The adsorption of small amounts of cationic CPC onto the primarily negatively charged surfaces of the particles in the pH range of 7?9 produces strong attraction and flocculation due to hydrophobic interactions.High concentration of surfactant under 0.01 mol/L of salt provides high zeta potential,which produces a high stability.

A New Ceramic Substrate Glaze with High Resistance to Molten Aluminum

Corrosion resistance of ceramic substrate glazes to molten aluminum was studied in this paper. The glazes can spread slightly in aluminum alloy according to SEM examination of solidified interface between the glazes and aluminum alloy. The components of B2O3-P2O5 glazes were not detected with electron probe at the side of aluminum alloy near the interface, but the components of boron-free glaze were detected. It is shown that borophosphate glazes can resist the corrosion of molten aluminum.

Influence of Rare Earth Composite Phosphate on Surface Free Energy of Ceramic Glaze

Rare earth composite phosphate (RECP) was doped into the ceramic glazes. The contact angle and surface free energy were characterized by the OCA-30 automatism contact angle test system. Through studied the influence of RECP on the surface free energy of ceramic glaze and movement modality of oil on the ceramic glaze in the water, the results show that the ceramic surface free energy increase obviously after dope RECP. Analysis and calculation show that the surface free energy increase mainly profited from the surface hydroxyl groups increase.

SELF-LUBRICATING BEHAVIOR OF Fe-Re BINARY ALLOYS

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Effect of heat treatment temperature of the glaze lager on the structure and the formaldehyde removal performance of an interior wall tile

With the improvement of people’s living standards,a large number of petroleum products,daily necessities and decorations that can produce volatile organic compounds are used in decoration,which seriously affects the indoor air quality.Interior decoration materials have become a research hotspot in recent years.The purpose of this paper is to develop a kind of interior wall material with good indoor formaldehyde removal effect,easily using,and low cost.In this paper,combining different heat treatment temperatures of the glaze layer,tourmaline/diatomite-based interior wall tiles were prepared by ultrafine grinding,solid sintering,and low temperature calcination.The glaze layer under different heat treatment temperatures was characterized by thermogravimetric-differential thermal analysis,X-ray diffraction,and scanning electron microscope.The influences of heat treatment temperature on the microscopic morphology and structure of the glaze layer were analyzed.Taking formaldehyde as the target degradation product,the effects of tourmaline/diatomite-based interior wall tiles on the removal of formaldehyde under different heat treatment temperatures of the glaze layer were investigated.The results showed that with the increase in heat treatment temperature,the original pores of diatomite decreased,the specific surface area decreased,and the structure of tourmaline changed.At 850℃,the surface structure of the material was slightly damaged,the strength was increased,and the removal effect of formaldehyde was better.In a 1 m^(3) environmental chamber,the formaldehyde removal rate reached 73.6%in 300 min.When the temperature was increased to 950℃ and above,diatomite and the structure of tourmaline were destroyed,and the ability of the material to adsorb and degrade formaldehyde decreased.