<strong><span lang="EN-US">Abstract:</span></strong><span lang="EN-US"> The effect of bismuth ion substitution on the magnetic properties of cobalt ferrite nanoparticles was identified in this study. This method used in this study was coprecipitation method using 0.1 bismuth ion concentration. The results on hysteresis loop showed that the saturation magnetization of cobalt ferrite nanoparticles decreased with the substitution of bismuth ions, but the coercive field experienced the opposite. Saturation magnetization decreased from 57.97 to 51.19 emu / g, while coercive fields increased from 0.64 to 0.84 kOe.</span>

The crystalline structure and magnetic properties of Mn_1-xCo_xFe₂O₄ (x = 0 &amp; 0.25) was studied in this report. The ferrite materials were synthesized by the chemical co-precipitation method and calcinated at 1000^oC for 5 hours. The obtained materials were characterized by FTIR, XRD and VSM, and for photocatalytic activity was measured by UV-Vis spectrometer. Vibration bands at tetrahedral and octahedral site were corresponded by <strong> </strong>= 581.56 cm^-1 and  = 465.83 cm^-1 and 474.51 cm^-1 . The obtained ferrite were confirmed by XRD as spinel structure and shown that the addition of number of Mn decreased crystallite size <em>(D)</em> and x-ray density (<em>ρ_x</em>), but lattice constants <em>(a)</em> increased. The crystallite size of samples with x = 0.50 was 34.85 nm, and x = 0.75 was 32.17 nm. The magnetic properties of nanoparticles shown that magnetization saturation <em>(</em><em>Ms)</em>from 42.05 emu/g to 54.16 emu/g increased with the addition of number of Mn. The coercive field (<em>H</em>_c)decreased from 408.27 Oe to 258.37 Oe. Photocatalytic activity was observed by UV-Vis spectrometer, where percentage of MB degradation <em>(E)</em> increase with the addition of number on Mn from 49.08% to 69.06%, either rate constant <em>(k_app)</em> and half life time<em> (t_1/2)</em>.  Furthermore, ferrite material base Mn-Co-ferrite has good characteristic to applied for photocatalyst.

INITIATING ENTREPRENEURIAL SKILLS THROUGH THE INTRODUCTION OF E-COMMERCE FOR ORPHANS OF THE MUHAMMADIYAH ORPHANAGE IN BLIMBING SUKOHARJO. Efforts to improve skills and the cultivation of entrepreneurial spirit have been carried out at the Orphanage PKU Muhammadiyah Cabang Blimbing. This institution is home to 20 orphans located in Wonorejo, Polokarto, Sukoharjo. Wonorejo village is a convection village where most of the population work as convection producers, which in the sale of their clothes still use conventional methods, which are sold in stores and in markets. The pattern of mutually beneficial cooperation between convection entrepreneurs and orphans is initiated by technopreneurship activities namely by selling convection through online stores.

IntisariSintesis dan fabrikasi lapisan tipis berbasis nanopartikel porphyrin alam dilaporkan pada makalah ini. Larutan porphyrin alam disintesis melalui proses permurnian dengan teknik kolom kromatografi kemudian ditumbuhkan menjadi lapisan di atas substrat Cu dengan metode spin coating. Hasil pengamatan dengan atomic force microscopy menegaskan bahwa lapisan tipis tersusun dari struktur islands dengan dimensi nano meter orde. Dimensi lateral lapisan tipis dengan N = 3 menunjukkan struktur island sebesar 800 nm yang lebih kecil dibandingkan sampel N = 5 yaitu 1200 nm. Pengamatan lebih detail untuk skala scan lebih kecil menegaskan bahwa dimensi islands yang besar merupakan himpunan islands kecil-kecil membentuk suatu ikatan tertentu. Akhirnya, jika satu unit islands merupakan sebuah molekul, maka island-island tersebut berinteraksi membentuk suatu supra-molekuler. ABSTRACTSynthesis and fabrication of nanoparticle-based thin layer of natural porphyrin is reported in this paper. Porphyrin solution was synthesized by using a process of natural purification with column chromatography techniques. It was then grown into a thin film an a Cu substrate by spin coating method. Observations with atomic force microscopy confirmed that the thin layer structure is with the composition of islands with dimensions of the order of nano-meters. The lateral dimensions of the thin layer with N = 3 showed the structure of the island of 800 nm which is smaller than the sample of N = 5 is 1200 nm. Moreover, an observation of smaller-scale scan confirmed that the islands which are larger dimension are composed of small islands with a certain bond. Finally, if the one unit of island is a molecule, the islands may interact to form a supra-molecular.

This research is motivated by the implementation of the field trip method by history subject teacher in Bukittinggi Senior High School, but there are still some steps in the field trip that are not yet in line with the theoretical field trip steps. This study aims to determine the appropriateness of the implementation of the field trip method carried out at Bukittinggi Senior high school by the history teacher with the theoretical field trip method steps. The subject of this research is the history teacher at Bukittinggi Senior High School. The method used in this study is an evaluative method with type of qualitative research. The results showed that in general the steps of the field trip had been carried out by the teacher well, but there weresome things that were not ideal, including : 1) the teacher had not clearly stated the purpose of the field trip method, this was related with conceptual skills not maximal from the teacher. 2) the teacher has not involved the child in determining the object of the field trip in the PjBL, This is caused by human skill factors that are applied by the teacher is still not optimal.