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Now a days Concrete is used as a construction material and it is available easy.it has some properties like strength, tensile, durability, etc. Sawdust and eggshell powder used as a natural material and it will reduce the cost of construction materials. Sawdust and eggshell powders are one mostly available waste materials on the earth, so we are using these waste materials as useful construction materials and we also improving the strength of concrete. Eggshell powder consist of high calcium percentage compared normal cement and sawdust is very low in weight but it has given the same strength like cement. We brought the eggshell powder and sawdust from my nearest area and we replaced cement weights with 5%, 10%and15%. We added 5% of eggshell powder and 5% of sawdust for 10% weight of cement, 10% of eggshell powder and 10%sawdust for 20% weight of cement, 15% of eggshell powder and 15% of sawdust for 30% weight of cement. The compression strength results by replacing 10% of cement has got 20.9N/mm2,by replacing 20%of cement as got 20.3N/mm2, by replacing 30% of cement as got 18.2N/mm2. We also done tensile strengths for cylindrical concretes and we got 3.2 N/mm2 by replacing 10% weight of cement and 3.5N/mm2 for 20% weight of cement and 2.4N/mm2 for 30% weight of cement. As per the reports 10% and 20% replacements given better strength compared to cement concrete. [ABSTRACT FROM AUTHOR]

Uncontrolled infrastructure expansion depletes natural resources, and waste plastics are regularly thrown into the environment and oceans, putting nature, humans, and aquatic life at risk. These risks can be mitigated by properly disposing of plastic waste. Plastic waste management, such as reusing building waste materials, reduces pollutants that cause pollution and the demand for natural resources. The primary purpose of this research is to look into the possibility of using waste plastic as a target material for partial volume reduction in concrete blocks. The single-use polyethene terephthalate (PET) trash is placed in a PET container and compressed securely with a tampered rod. The PET bottle's opening is sealed with a polypropylene plastic cap. A concrete mix grade of (M25) is employed for this experiment. [ABSTRACT FROM AUTHOR]

Glasses with the composition xBaO-(30-x) TeO2-10TiO2-59B2O3-1CuO (where x = 10, 15, 20 and 25 mole %) were prepared by melt quenching technique. The XRD studies were made on these glass samples at room temperature. The amorphous nature of the glass samples was confirmed from the XRD patterns. The physical parameters such as density (ρ), molar volume (Vm), average boron-boron separation (dB-B) and oxygen packing density (OPD) were calculated. The change in density and molar volume has been investigated in terms of the variation of BaO in the glass composition. The optical absorption spectra have been recorded at room temperature. The values of optical band gap have been estimated from the ASF and Tauc’s methods. Both Tauc’s and ASF methods have been showing progressively increasing indirect optical band gap values with the increase of BaO concentrations. [ABSTRACT FROM AUTHOR]

Glass containing Cu2+ ions in (30-x) BaO-xAl2O3−69.5B2O3-0.5CuO (0 ≤ x ≤ 15 mol %) were prepared by the conventional melt quenching technique. Peak free X-ray diffractograms confirmed the amorphous nature of the glass samples. Spectroscopic studies such as optical absorption, EPR were studied to understand the effect of modifier oxide and CuO dopant. From EPR spectra the spin-Hamiltonian parameter were evaluated. The ground state of Cu2+ is d x 2 − y 2 (2B1g state) and the site symmetry around Cu2+ is tetragonally distorted octahedral. A broad optical absorption band was observed for all the glasses containing Cu2+ ions corresponding to the 2B1g → 2B2g transition. The optical band gap and Urbach energy values are calculated. [ABSTRACT FROM AUTHOR]

Spectroscopic and physical properties of V2O5 doped mixed alkali borate glasses are investigated. Borate glasses containing fixed concentrations of alkaline earth oxides (MgO and BaO) and alkali oxides (K2O and Na2O) were changes and are prepared by melt quenching technique. The values of ri, rp, Rm, αm molar volume and Λth increase and oxygen packing density, density and dopant ion concentration decrease with increasing of K2O content. As a result there shall be an increase in the disorder of the glass network. The optical band gap energies, Urbach energy, boron-boron separation, refractive index, dielectric constant, electronic polarizability and reflection loss values are varies nonlinearly with the K2O content which manifests the mixed alkali effect. [ABSTRACT FROM AUTHOR]

Electron Paramagnetic Resonance (EPR) studies at room temperature in the x-band frequencies on xZnO- 10Li2O-10Na2O-10K2O-(69-x)B2O3-1CuO (x=0,2,4,6 and 8 mole%) glass systems were reported. The non-linear variation of spin-Hamiltonian parameters with ZnO content indicated the change in the ligand field strength around Cu2+ ions in the host glass. The ground state of Cu2+ ions in the glass is designated as dx²-y² orbital (²B1g) while the observed symmetry around it is tetragonally distorted octahedral. The molecular orbital coefficients ɑ², β² and β1²are evaluated for Cu2+ doped samples. The non-linear variation in the values of parameters indicated mixed alkali effect in the glasses. [ABSTRACT FROM AUTHOR]

Borate glasses containing different concentrations of heavy metal oxide (CdO) with 2mol% of V2O5 as the paramagnetic probe were prepared by the conventional melt quenching technique. The prepared glasses were characterized by XRD to confirm the amorphous nature. EPR and Optical absorption studies were carried out at room temperature. EPR spectra of these glass samples were recorded at X-band frequency with 100 kHz field modulation at room temperature. From the EPR spectra the spin-Hamiltonian parameters were evaluated. The spin-Hamiltonian parameter values indicated that g|| < g┴ < ge [=2.0023] and A∥︀ > A┴. This suggests that VO2+ ions are present in octahedral sites with tetragonal compression and belong to C4v symmetry with dxy being the ground state. The measure of tetragonal distortion (Δg∥︀/Δg┴)varies non-linearly with glass composition indicating change in tetragonal distortion. The covalency rates were estimated. The number of spins participating in the resonance [N] and susceptibility (χ) values were also evaluated. [ABSTRACT FROM AUTHOR]

The 'mixed alkaline effect' is one of the classical anomalies of glass science. We report here an interesting phenomenon 'Mixed Alkaline earth oxide Effect' observed in a series of VO2+ ions doped in xMgO-(30-x)BaO-68B2O3-2V2O5 glass system. Glasses are investigated by EPR technique at X-band frequencies. The EPR spectra of all the glasses exhibited resonance signals characteristic of VO2+ ions in octahedral coordination with tetragonal compression and have C4V symmetry with ground state dxy. Tetragonality (Δgll/Δg⊥) of V4+ ion sites exhibited non-linear variation with MgO content, which indicated change in the ligand field at the site of V4+. [ABSTRACT FROM AUTHOR]