Electrodeposition of paramagnetic copper (Cu) from a sulfate solution was investigated under magnetic fields and two different current densities. Static magnetic fields have been used during electrodeposition of paramagnetic Cu onto paramagnetic aluminum (Al) substrate to enhance the deposition rate and to alter crystallographic orientation and morphology of the film. The magnetic field might be attributed to the field-induced convection that disrupts the depletion layer near the electrode and that might also be correlated to Cu, Al, and oxygen dissolved in the solution as paramagnetic materials. An X-ray diffractometry, a scanning electron microscope with energy dispersive spectrometry, a potentiostat, and a digital camera were used for characterizing the crystal structure, morphology, the electrochemical behavior, and wettability, respectively. The results show that, at the current density of 10 mA cm −2 , raising the magnetic field from 800 to 1400 G increases the cathode current efficiency and alters the electrochemical behavior, the crystal growth, and the crystallite size. At the current density of 30 mA cm −2 , the magnetic field alters the growth and crystallographic orientation. The static magnetic field exposed during electrodeposition of Cu onto the Al alloy can control the film properties, especially crystallographic orientation and the oxygen content.

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XYZ is a company that provides building maintenance services; one of its services is glass cleaning services. In every work on building maintenance services projects in the form of cleaning the glass of PT. XYZ has not calculated the standard time of work, which affects 45% of the total work exceeding the deadline for the job given and the difficulty of estimating the productivity of the workers. In this study, the standard time and productivity were determined on the glass cleaning work of building X using the stopwatch time study method. The results of the calculations carried out using the stopwatch time study method obtained the optimal normal time at each stage of the work, namely in the preparation of work equipment for 58.55 minutes, on the removal of the gallows 112.82 minutes, on the installation of ropes of 20.41 minutes, on machine checking is 22.29 minutes, glass cleaning is 54.17 minutes, rope disassembly process is 57 minutes, and gondola storage is 55.33 minutes so that the optimal standard time is 380.56 minutes. Calculation results showed that performance rating measurement, excellent skill is B1 +0.11, a good effort is C1 +0.05, good condition is C +0.02, consistency is C +0.01 with a rating factor obtained in normal time is 65.569 minutes, and from the results of the calculation of worker productivity in the work of cleaning the glass of building X was obtained 0.12 units/hour.

Study of igneous rocks derived from Ogowele Village and Village Toli-Toli Bajugan has been conducted to determine the magnetic minerals contained in the igneous rocks, as well as determine the crystal system, lattice constants and field diffraction by comparison sieve 60 mesh and 80 mesh. Process characterization and analysis using X-Ray Diffraction (XRD). Characterization and analysis of the results showed that the compound was detected both rock samples Fe3O4, SiO2, Al2O3 and MnO2. Igneous rocks derived from Ogowele village is dominated by compounds SiO2 (quartz) by 52% and rocks from Bajugan village dominated by the compound Fe3O4 (magnetite) by 40%. The crystal structure is cubic and hexagonal compound to compound Fe3O4 SiO2. Fe3O4compound cubic lattice constants are a = b = c is 8.375 Å. To compound the hexagonal SiO2 ie a = b of 4.898 Å and c of 5.385 Å. Field diffraction on Fe3O4compound is (3 1 1) and the SiO2 compound that is (1 0 1).