It has been investigated the effect of firing temperature on water absorption and flexural strength in the manufacture of BL1P code stoneware ceramics. Ceramics are made in the form the test block bar with materials from of Borneo Clay Noodle, PRC Feldspar, Kaolin Belitung, Belitung Quartz, Ballclay Bantur, Bentonite, and Talk with a simple casting method. The block bar of the molds was burned at four temperature variations, i.e. 850, 900, 1000, and 1200 oC. From the results of measurements of it water absorption, it was found that the increase in firing temperature from 850 oC to 1200 oC showed a decrease in water absorption from 18.3% to 5.5%, while the measurement of it flexural strength showed an increase in flexural strength of 11.6 kg/cm2 to 19.8 kg/cm2.

No abstract

Magnetite (Fe 3 O 4 ) crystals have been synthesized from the natural iron sands of Tegal Lenga Beach with HCl (37%) as a solvent. Tegal Lenga Beach is a stretch of beach located in Kalisada Village, Seririt District, Buleleng Regency, Bali Province, Indonesia. Iron sand samples were obtained by extracting local natural sand from Tegal Lenga Beach by magnetic separation method. The iron sand sample was ground with agate mortar for 15 hours, then washed and rinsed with deionized water (DI water). Furthermore, the fine powder sample of iron sand was dried on a hotplate at a temperature of 80˚C until all the water had evaporated. Eighty grams of fine iron sand powder dissolved in 200 mL HCl (37%) while stirring with a hot plate magnetic stirrer at a temperature of 100˚C with a rotating speed of 600 rpm for 30 minutes. This solution was filtered through Wattman filter paper No. 42; then the filtrate was dried using a hot plate at a temperature of 100˚C to form a crust. This crust is then ground in an agate mortar until it becomes a fine powder of iron sand. Furthermore, the iron sand fine powder filtrate sample was divided into four equal parts which were then calcined at temperatures of 300˚C, 400˚C, 450˚C, and 500˚C for 30 minutes, respectively. It was found that the fine powder of iron sand from the natural sand of the Tegal Lenga Beach consisted mostly of 84.26% metal oxide magnetite. The synthesized magnetite crystal has a tetrahedral structure with lattice parameters of a = b = (5.927 ± 0.0180) Å and c = (16.774 ± 0.0145) Å. Magnetite crystals have granular and lumpy grains with an average grain size of (94,560 ± 10,1397) μm. In relation to the values obtained from the hysteresis curve, namely the remanent magnetization of 9.6672 emu/gr, saturation magnetization of 45.3491 emu/gr, coercive magnetic field strength of 0.0242 T, and saturation magnetic field strength of 0, 2938 T, then this magnetite crystal is classified as a weak ferromagnetic material.

Tumors are caused by uncontrolled growth of abnormal cells. Magnetic Resonance Imaging (MRI) is modality that is widely used to produce highly detailed brain images. In addition, a surgical biopsy of the suspected tissue (tumor) is required to obtain more information about the type of tumor. Biopsy takes 10 to 15 days for laboratory testing. Based on a study conducted by Brady in 2016, errors in radiology practice are common, with an estimated daily error rate of 3-5%. Therefore, using the application of artificial intelligence, is expected to simplify and improve the accuracy of doctor's diagnose.

Investigation of the substitution process can provide a better understanding of the superconducting mechanisms in cuprous oxide materials. In this work the effects of substitution Lanthanum (La) for Gadolinium (Gd) on the structure and oxygen content for x = 0.0 -0.5 in the compound Gd 1-x La x Ba 2 Cu 3 O 7-δ (GLBCO-123 phase) have been investigated. Samples were synthesized by using a wet-mixing method from powders of Gd 2 O 2 , La 2 O 2 , BaO, CuO, and solution of HNO 3 . Based on the analysis of XRD data and SEM-EDXA, it confirms that the sample has formed the GLBCO-123 phase, as expected. It has been obtained that the lattice parameters a and c are increased while the parameter b is slightly decreased with increasing content of Lanthanum. The oxygen content slightly decreased and structure of the Gd 1-x La x Ba 2 Cu 3 O 7-δ phase changed from orthorhombic to tetragonal with increasing the content of Lanthanum.