This study focuses on recycling of different industrial wastes as silica fume and waste clay for production of structural sintered alumino-silicate ceramic bodies. These wastes are rich in important metal oxides like silica (SiO2) and alumina (Al2O3) which are useful for production of alumino-silicate ceramics by solid-state route. Different batches were designed, pressed and sintered at different temperatures using silica fume and waste clay mixtures. The sintered bodies were tested by various techniques. The bulk density and apparent porosity were examined by liquid displacement method. The formed phases of sintered ceramic bodies were identified by x-ray diffraction technique. The microstructure of sintered ceramics was examined by scanning electron microscope (SEM). Thermo-mechanical properties in terms of compressive strength, thermal shock resistance and thermal corrosion resistance against soda-lime glass were also investigated. The results revealed that thermally stable and corrosion resistant alumino-silicate ceramics were successfully fabricated from silica fume and waste clay after sintering at 1400oC. The fabricated ceramic bodies composed mainly of mullite, cristobalite and glassy phases. The amount of mullite is decreased while the amount cristobalite and glassy phases are increased with increasing the amount of silica fume. The apparent porosity decreased with increasing both sintering temperature and amount of added silica fume due to the formation of higher amounts of liquid phases. The phase composition and porosity of sintered ceramics influenced on the compressive strength, thermal shock resistance and corrosion resistance against soda-lime glass. Thermal shock resistance and corrosion resistance are improved with increasing the amount of formed mullite.

The main objective of this study is to fabricate composite materials having excellent thermal, mechanical and electrical properties for thermal and electronic applications. In this work, strontium feldspar -containing composites (Sr-feldspar/cordierite and Sr-feldspar/Sr-osumilite) were prepared by solid-state sintering of SrOcontaining cordierite (MgSrAl 4 Si 5 O 18 )/borosilicate glass powder mixtures. The phase composition, physical properties and microstructure of sintered composites were investigated by X-ray diffraction technique, water displacement method and scanning electron microscope, respectively. Moreover, the thermal expansion coefficient, hardness, and electrical properties were also measured. The results of X-ray patterns revealed the crystallization of Sr -feldspar and cordierite in the composites that contain up to 20% borosilicate glass. On the other hand, the composites that include more than 20% glass, displayed the crystallization of Sr -feldspar and Srosumilite with little amount of cristobalite. The bulk density values of sintered composites were decreased from 2.41 to 1.84 g/cm 3 with increasing the amount of added glass. The microhardness values were increased from 519 to 710 kg/mm 2 with increasing the glass content. Low thermal expansion coefficient (2.65 x 10 -6 , 2.22 x 10 -6 , 3.45 x 10 -6 and 4.26 x 10 -6 K -1 for C0, CG91, CG73, CG55, respectively) and low dialectic constant (7 -8.5) were obtained for the prepared composites.

This study focuses on the relationship between porosity, surface roughness, microstructure, strength, and thermal properties, as well as their effect on the bioactivity and biodegradability of fabricated akermanite (AK; Ca2MgSi2O7) bioceramic scaffolds. Firstly, we prepared the AK nanopowders using the mechanical activation method, mixed them with varying proportions of space-holder agent (NaCl), specifically 15, 20, 30, 40, and 50 vol.%, and sintered them at 1200 oC to create porous scaffolds. We investigated the physical properties and microstructure using the Archimedes method and field emission scanning electron microscopy (FE-SEM), respectively. The mechanical properties in terms of microhardness, compressive strength, longitudinal modulus, Young’s modulus, bulk modulus, and shear modulus were measured. The bioactivity and biodegradability of prepared scaffolds were assessed after soaking in simulated body fluid (SBF) for 10 days by FE-SEM and inductively coupled plasma-atomic emission spectroscopy (ICP-AES), respectively. The results revealed that porous scaffolds with suitable mechanical properties, bioactivity, and biodegradability were prepared. The porosity had a significant impact on the mechanical and biodegradability of the investigated scaffolds. It reduced mechanical properties slightly while improving bioactivity and biodegradability. The microstructure study displayed that all scaffolds formed apatite layer on their surfaces. This is because of good bioactivity and the suitable porosity level of AK. The obtained findings provide promising prospects for the future use of AK in bone tissue engineering.

The main objective of this study is to enhance the physical and mechanical properties of geopolymers fabricated from waste clay through incorporation of synthetic TiO2 nanofibers. Firstly, the nanofibers were chemically synthesized, annealed at 550 °C and then characterized by different tools as x-ray diffraction (XRD), FT-IR, scanning electron microscope (SEM) and transmission electron microscope (TEM). Secondly, three geopolymer batches included 0.1, 0.3 and 0.5 wt.

The main goal of this study is to investigate the effect of granite powder on the hydration characteristics of volcanic ash (85 %) - lime (15 %) cement pastes. The granite powders (10, 20 and 30 wt%) were added at the expanse of volcanic ash in the cement mixes. The casted cement cubes were cured under water (water-hydrated) or cured in air (air-hydrated with spraying of water every day), for 3, 7, and 28 days. XRD, FTIR, TG, and SEM, techniques were used to monitor the phase composition, thermal analysis and microstructure of the hydrated cement pastes. The chemically combined water, bulk density, apparent porosity, and compressive strength were also determined for the hydrated cement pastes. The results reveal that amorphous and crystalline hydrated phases as well as amorphous calcium-modified silica gel in addition to other minor phases were formed after curing in water or air. Generally, the pozzolanic cement pastes cured in air exhibited improved mechanical properties than that cured in water. Furthermore, the mechanical properties were improved with increasing curing time. Moreover, the substitution of volcanic ash by granite by up to 30 % did not affect the mechanical strength of cement pastes cured in water. On the other hand, the substitution of volcanic ash by granite in mixes cured in air exhibit slight reduction in compressive strength after addition granite. The granite granules act as nucleation sites on which the hydrated phases are deposited.

This work focuses on fabrication of 80 alumina/(20-x)zirconia/xHA (x = 0.0. 5.0, 10.0 and 15 wt.

The current study focuses on the development and fabrication of ceramic nano inks with improved properties. Firstly, two types of pigments were prepared through a solid state process using fine gibbsite (Al(OH)3) or aluminum chloride (AlCl3) with cobalt chloride hexahydrate (CoCl2.6H2O). The stoichiometric precursors were well-mixed and fired at 1000oC; then milled by a high energy ball mill to obtain nano pigments. The prepared pigments were investigated for their phase composition and crystallite size by X-ray diffraction, and further confirmed by Fourier Transform Infrared (FTIR). The morphology and particle size were examined using a scanning electron microscope. The optical properties in terms of UV-Vis, photoluminence emission spectra and CIE chromaticity diagram were also tested. The chemical-state of cobalt and surface elemental composition of prepared Co-aluminate pigments were tested by X-ray photoelectron spectroscopy (XPS). Four groups of ceramicinks (twelve formulations) were prepared using different percentages of cobalt aluminate pigments and additives. The fabricated inks were investigated for their morphology, rheology, contact-angle and sedimentation behavior. The results revealed that two cobalt aluminate pigments with spinel structure, nano sized particles and blue color, were successfully prepared by the proposed method. The results of optical properties indicated that the cobalt ions are located mainly in tetrahedral sites with a small amount in octahedral sites. The prepared pigments were successfully used in the fabrication of ceramic nano inks with improved properties. The viscosity of most fabricated inks was in the range needed for the industry (4-40 mPa s).

The main goal of this work is to study the effects of some transition metal-oxides, i.e. ZnO, TiO 2 , and Fe 2 O 3 , on inhibition of spinel formation during cordierite fabrication from granite waste, talc, and alumina by direct coagulation casting method. Moreover, the effect of these oxides on sinterability, microstructure, hardness and electrical properties was achieved. The casted specimens were sintered at different temperatures then examined by X-ray diffraction technique to follow the formed phases. The physical properties were determined according to Archimedes rule. The microstructure was also investigated by scanning electron microscope, while the hardness was determined by Vicker’s method. The electrical properties were evaluated by an impedance analyzer. The results indicated that sintered cordierite-spinel ceramics were successfully prepared with inhibition of spinel formation after addition of some transition metals and sintering up to 1250 °C. ZnO promoted the formation of spinel while TiO 2 and Fe 2 O 3 inhibited the formation of spinel and promoted the formation of cordierite. The ZnO-containing cordierites exhibited their best properties after sintering at 1200 °C, while the samples containing TiO 2 and Fe 2 O 3 showed their best properties after sintering at 1250 °C. The physical, mechanical and electrical properties were improved after increasing the amount of added metal oxides. The dielectric constant values were higher for the samples that contain TiO 2 than those contain Fe 2 O 3 and ZnO. Moreover, the hardness of all samples was in a narrow range of 6.14–6.61 GPa.

The main goal of this study is to recycle Cyclones’ waste clay for production of environmental friendly green and thermally stable geopolymers. Cyclones’ clay is a by-product produced in huge amounts after refractory industry. In this context, geopolymer was prepared from Cyclones’ clay and alkali activators at 70 °C. To study their thermal stability against firing, the prepared geopolymers were fired at 800 °C and 1000 °C with low heating rate. The qualitative phase analysis/elucidation of dried and fired geopolymers was evaluated by X-ray technique and Fourier transform infrared. The apparent porosity and bulk density were determined by liquid displacement method, while the linear shrinkage was calculated according the initial and final dimensions of the specimens after drying/firing. The microstructure was examined by scanning electron microscope, while compression strength was also determined. The results showed the recycling of waste clay for fabrication of green and thermally stable geopolymers was successfully conducted. The fabricated geopolymers exhibited interesting physical and mechanical properties with a developed microstructure. After firing, thermally stable ceramic bodies were obtained with the formation of new crystalline phases. The apparent porosity and bulk density of green geopolymer were changed after firing; the apparent porosity was decreased while the bulk density was increased. All prepared green and fired geopolymers exhibited good mechanical properties. The green geopolymer exhibited 37.7 MPa, while the geopolymers fired at 800 °C and 1000 °C exhibited 42 and 65 MPa, respectively.

This study focuses on recycling of ladle furnace slag for fabrication of geopolymer. Moreover, its application as a catalyst for biodiesel production is the main goal of this study. Several batches of geopolymer were prepared from ladle furnace slag and metakaolin in the existence of alkali activator. Phase identification of prepared geopolymers was inspected by x-ray diffraction and FT-IR while the physical properties (bulk density and apparent porosity) were examined giving the Archimedes' rule. Furthermore, the compressive strength was also tested. An attempt for application of prepared geopolymers as catalyst for biodiesel production was conducted using geopolymer fine powders (calcined at different temperatures) and soybean oil in presence of methanol. To evaluate the efficiency of prepared biodiesel, its density, Kinematic viscosity and flash point were determined. The results revealed that geopolymer bulk materials were successfully prepared from ladle furnace slag and kaolin. The prepared geopolymers have good physical and compressive strength. The best compressive strength (21 MPa) of prepared geopolymer was obtained for the batch composed of 60% ladle furnace slag and 40% metakaolin. Also, the results of density, viscosity and flash point of produced biodiesel were in the standard range, i.e. 0.848-0.885 g/cm3, 2.8-5.1 mm2/s and 90-135 degrees C, respectively.

In this study, amorphous ZnO-containing calcium silicate nano powders were prepared by sol–gel technique and then calcined at different temperatures; namely, 600, 800 and 1000 °C, to study their crystallization. The synthesized powders were examined by X-ray diffraction (XRD) technique, Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). Then, the synthesized powders were sintered at different temperatures. The sintered ceramics were examined for their physical properties, microstructure, mechanical properties and electrical properties by the suitable techniques. The results revealed that the synthesized nano powders were amorphous even after calcination up to 800 °C. By increasing the calcination temperature into 1000 °C, crystalline calcium silicate ceramic was formed. The average particle size of this crystalline material was 50 nm with lower agglomeration among the others calcined at low temperatures. Regarding to the sintered ceramics, the bulk density, fracture toughness and electrical conductivity were increased with increasing both sintering temperature and zinc content. On the other hand, microhardness, compressive strength, elastic moduli and Poisson's ratio were increased with increasing sintering temperature and decreased with increasing the zinc content.

This work focuses on recycling of Cyclone's waste clay in the existence of various percentages of submicron sand (400-800 nm), i.e. 2.50, 5.00 and 7.50 wt-%, for production of hardened and fired geopolymer mortars. After drying the hardened geopolymer mortars, they were subjected to low rate firing at different temperatures, i.e. 800, 1000, and 1200 degrees C. The physico-mechanical properties of dried and sintered geopolymer mortars were investigated by various tools. The apparent porosity and bulk density were tested by water-displacement method. The mineralogical composition and reaction products were identified by X-ray diffraction technique and Fourier transform infrared spectroscopy, respectively. The microstructure was investigated by scanning electron microscopy. The compression strength was also evaluated. The results revealed that the addition of submicron sand to geopolymer mortars enhances the physico-mechanical properties of geopolymer mortars. The mortar that contained 7.5 wt-% submicron sand exhibited lower porosity (25%) and the highest compressive strength (27 MPa) as compared to the other mortars. After firing, the mortars fired at 1000 degrees C exhibited improved properties than that fired at 800 degrees C, while that fired at 1200 degrees C was deformed and fused. On the other hand, the mortar that contains 2.50 wt-% submicron sand showed the best physico-mechanical properties as compared to the other ones. It exhibited the lower porosity (2.50 wt-%) and the highest compressive strength (85 MPa) after firing at 1000 degrees C.

This study focuses on recycling of granite sludge for production of cordierite-spinel composites prepared by direct coagulation method. Furthermore, the effect of transition metal oxides (CuO, NiO, and MnO2) on their in-situ formation, sinterability and properties (mechanical and electrical) was studied. The granite sludge, talc, and calcined alumina were utilized to prepare cordierite-spinel composites. Firstly, talc and alumina were mixed and fired at 1350 °C, then mixed with granite sludge and transition metal oxides to be ready for casting by direct coagulation method after adjusting the appropriate conditions. The casted specimens were firstly dried then sintered at 1200 and 1250 °C. The phase composition and physical properties of sintered composites were investigated by x-ray diffraction technique (XRD) and Archimedes method, respectively. The microstructure was investigated by scanning electron microscope while the hardness was tested by Vickers indentation method. The electrical properties of sintered bodies were also evaluated. All XRD patterns showed formation of cordierite and spinel phases after addition of metal oxides and sintering at 1200 or 1250 °C. Also, the results indicated enhancement of densification parameters for CuO- and MnO2-containing composites after sintering at 1250 °C while for NiO-containing composites, they enhanced after sintering at 1200 °C. Furthermore, the densification parameters were improved with increasing metal oxides contents. The highest hardness value (8.3 GPa) was obtained for 6

This work focuses on recycling of rice husk for production of activated carbon/Fe3O4 nanocomposite. Moreover, the synthesized composites were applied for elimination of methylene blue dye from wastewater. The proposed nanocomposite can replace pure activated carbon which is expensive and has some difficulties during its reusability. First, the activated carbon was extracted by thermal and chemical activations of rice husk ash. On the other hand, the activated carbon/magnetite nanocomposite was prepared by co-precipitation method using the suitable iron salts. The qualitative phase identification of prepared composite was performed by X-ray technique (XRD) and confirmed by Fourier Transform Infrared Spectroscopy (FT-IR). The morphology and particle size of prepared activated carbon and its composite were investigated by transmission electron microscope (TEM). The batch-adsorption method was utilized for studying the elimination of methylene blue dye from wastewater. Various factors like adsorbent dosage, pH of reaction, initial dye concentration, and duration of reaction were examined. The results showed that the prepared nanocomposite was almost amorphous as indicated from XRD patterns. Also, its particle size was very small (5–10 nm) and lower than the activated carbon alone (40–80 nm). Regarding the removal percentage of methylene blue dye from waste water, 98

The recycling of waste materials for production of innovative materials is considered as an interesting point of research and urged the scientists to deal with. This study focuses on the preparation of activated carbon (AC) from sugarcane bagasse waste material. Also, AC/magnetite nanocomposite was prepared by chemical precipitation of magnetite on the prepared AC. The synthesized AC and AC/magnetite were utilized as adsorbents for removal of crystal violet basic dye (CV) from wastewater. The prepared AC and AC/magnetite were investigated by surface area analyzer, X-ray diffraction, Fourier transform infrared spectroscopy (FT-IR), and Raman spectroscopy. To investigate the adsorption of CV by synthesized AC and AC/magnetite, batch adsorption process was conducted with varying different parameters as pH, contact time, and the dose of adsorbents. The equilibrium isotherm was examined by Langmuir and Freundlich models. Moreover, the adsorption kinetic was explored using pseudo-first-order and pseudo-second-order models. The results showed that the AC and AC/magnetite nanocomposite were successfully prepared by the proposed methods. AC/magnetite composite exhibited higher removal percentage (95.6%) for CV from wastewater than AC alone (92%) and the adsorption process proceeded by Freundlich isotherm. The obtained adsorption kinetic data indicated that the process fitted with pseudo-second-order model. The findings of this study recommend that AC and AC/magnetite nanocomposite could be used successfully for the removal of CV from wastewater.

This study focuses on fabrication of some spinel composites from pure and waste materials for electronic and magnetic applications. Six batches were designed from pure MgO, ZnO, Fe2O3, MnO2 and iron oxide extracted from alum sludge. The designed batches were sintered at 1250 and 1350 degrees C then investigated for their phase composition, microstructure, physical, mechanical, electrical and magnetic properties. The results indicated that, after sintering at 1350 degrees C, all batches formed spinel structures as main phases. The formed spinel structures were MgFe2O4, MgMn2O4, ZnMn2O4 and ZnFe2O4, in addition to some minor pervoskite structures. The batch that prepared from pure manganese and zinc oxides (B4), formed ZnMn2O4 spinel and exhibited the best densification parameters (bulk density; 4.7 g/cm3 and apparent porosity; 10%) as well as highest hardness (4.53 GPa). On the other hand, the specimen that fabricated from pure MgO, MnO2 and Fe2O3 (B2) formed MgFe2O4 and MgMn2O4 spinel structures and exhibited the highest electrical resistivity (1.3E + 09 Ohm.cm) as well as highest saturation magnetization (Ms = 24.948 emu/g).

The current study aimed to estimate the seasonal abundance of aphid species and their associated parasitoids on navel orange trees across the two seasons of 2021 and 2022 and to evaluate the potential impact of Aphidius matricariae Haliday against Aphis gossypii (Glover) during the period extended from August 2022 to January 2023. The results showed that the major aphid species were A. gossypii, Aphis citricola (van der Goot), Myzus persicae (Sulzer), and Aphis craccivora Koch. Data also revealed that A. matricariae, Trioxys sp., and Praon sp. were recorded as primary parasitoids and Charips sp. as a hyperparasitoid parasitoid. The behavior of A. matricariae varied according to the different host densities, since increased host density led to increased stings and mummies, and decreased leaf arrival times and host arrival times. By rearing A. matricariae on A. gossypii for three successive generations, the sex ratio (females: males) was nearly 1: 1 in the first two generations, but males dominated in the third ones (2.83:1). The obtained results showed that the parasitoid A. matricariae was the most abundant and efficient species and could be included in future biocontrol programs against A. gossypii.

Saleh, A.A.A., H. El-Nagar, A.A. Khalifa and M.F.M. Zawrah. 2023. The Role of Chrysoperla carnea (Steph.) and Beauveria bassina for Controlling Cabbage Aphid, Brevicoryne brassicae L. on Cabbage Plants. Arab Journal of Plant Protection, 41(3): 321-326. https://doi.org/10.22268/AJPP-041.3.321326 Field experiments were carried out at Kafr Saqr district, Sharkia governorate during 2019/2020 and 2020/2021 growing seasons to evaluate the predator:prey ratios for the release of C. carnea and evaluation of using Beauveria bassiana suspension against the cabbage aphid, Brevicoryne brassicae. The results obtained showed that the effective control of B. brassicae was achieved ten days after releasing the larvae of the predator C. carnea when the predator:prey ratios were 1:5 and 1:10. Meanwhile, at higher ratios (1:20, 1:25 and 1:50), the cabbage aphid B. brassicae numbers decreased 25 days after predator release. The numbers of B. brassicae decreased by 84.69 and 81.61% at 1:5 and 1:10 predator:prey ratio during the first season, respectively. On the other hand, the aphid numbers were reduced by 81.50 and 70.95% at 5 days after the predator’s release during the second season, for the two predator:prey ratios, respectively. Complete reduction of B. brassicae populations was achieved at 15 days after yhe release of C. carnea larvae with predator ratios of 1:5, 1:10 and 1:15, and numbers of B. brassicae at these ratios depressed completely 20 days after release. The results revealed that the best control of B. brassicae populations under greenhouses conditions was achieved by using the lower predator:prey ratio of 1:5 and 1:10 ten days after releasing larvae of C. carnea. The highest mortality rate in B. brassicae population caused by the fungus B. bassiana was 88.33%, recorded at 7 days after the application of spore concentration 1×107 spores/ml and the LC50 obtained in the field was 1.10×106 spores/ml. It can be concluded from this study that C. Carnea and B. bassiana are effective biocontrol agents in controlling the cabbage aphid B. brassicae in the field. Keywords: B. brassicae, Chrysoperla carnea, Beauveria bassiana, Predator release.

Ceramics are inorganicInorganic nonmetallic materials (oxides, carbidesCarbide, nitridesNitride, etc.) processed after sinteringSintering of natural or syntheticSynthetic precursorsPrecursor at high temperatureTemperature. They can also be applied at or resist high firingFiring temperatures. They are highly crystalline (most of the advanced and traditional ceramicsCeramic), semi-crystalline (vitrified ceramics such as earthenwareEarthenware, stoneware, andPorcelain porcelain), or completely amorphousAmorphous (glasses). The composition/structureStructure relationship, method of processing, raw materialsRaw materials, and applicationsApplication determine the propertiesProperties of ceramicsCeramic and whether the ceramics are traditional or advanced ones. The first man-made ceramics were potteryPottery objects and figurines from claysClay after firingFiring. Several stages have been considered in the development of ceramic industryIndustry until reaching the production of advanced ceramicsAdvanced ceramics. The second stage for development of ceramicCeramic includes the production of glazed-colored ceramics, ceramic arts, and building products. Recently, new categories of advanced ceramicsCeramic have been developed for electronicsElectronics, biomedicalBiomedical, semiconductorsSemiconductor, energyEnergy, and optical and structuralStructural applicationsApplication. In the present chapter, we are going to shed lightLight on the stages of development for advanced ceramicsAdvanced ceramics. Types and classifications, advanced processing techniquesProcessing techniques, propertiesProperties, sinteringSintering as well as new forms of applications will be presented in the currentCurrent chapter. Examples of these kinds of advanced ceramicsAdvanced ceramics, e.g., aluminaAlumina, zirconiaZirconia, Mg–Al spinels, silicon carbideSilicon carbide, silicon nitrideSilicon nitride, ceramic compositesCeramic composite, thin filmsThin film, etc., with their specific applicationsApplication will be also presented.

The main goal of the present study is to add graphene lubricant to enhance the microstructure and physicomechanical properties of aluminum matrix composites. The proposed composites were prepared by mechanical alloying technique, and the graphene was added with different contents up to 0.8 wt.% as reinforcement. X-ray diffraction analysis and transmission electron microscopy were employed to inspect milled powders' phase changes and particle features (shape and size). The obtained powders were sintered at 400, 500, and 570oC. The microstructure of fired composites was tested by scanning electron microscopy. The physical properties, hardness, compressive strength, strengthening factor, elastic-moduli, and electrical conductivity were also measured. The results displayed that the graphene particles are homogenously distributed through the Al matrix after milling. The particle size of milled powders was about 31.6 nm with an obvious degree of agglomeration. The mechanical properties of sintered composites were affected significantly by sintering temperature and graphene content as dominant factors. The highest obtained microhardness and compressive strengths were 920.8 MPa and 292.1 MPa. They achieved the composite that contains 0.8 wt.% of graphene (AG0.8). Moreover, the conductivity was decreased slightly with the increase of graphene, but it was increased with increasing sintering temperature.