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Modifications of the Microbial Fuel Cell (MFC) membrane need to be carried out to increase its electric potential energy. This research aims to determine the effect of montmorillonite from bentonite-Ca as a composite in modified earthenware (GT), which is then used as a membrane of the MFC-based on tempe wastewater as substrate. The results obtained were compared to MFC that used pure earthenware membrane (GM). The ratio of bentonite-Ca and clay in GT was 50:50, while GM used 100% of clay. Characterizations of GT dan GM were performed using FTIR, XRD, and SAA. MFC testing was carried out for 24 hours, where every 2 hours, measurements of potential difference (V), current (A), and power density (W/cm2) were carried out. FTIR and XRD data showed an increase in montmorillonite content in GT, while SAA data showed a decrease in pore volume in GT. The decrease in pore volume GT occurs due to an increase in the number of trivalent cations (Al3+, Fe3+) and bivalent (Mg2+). These cations help transfer protons from the anode to the cathode, which causes a decrease in the potential difference and an increase in the current strength and the MFC-GT power density. The average difference between the decrease in potential difference from MFC-GM to MFC-GT is 0.043 V, while the increase in current is 0.022 mA, and the increase in power density is 0.163 mW/cm2.

The theoretical study of the use of cyano acid derivatives as electron acceptor groups in pelargonidin as a dye compound in sensitized solar cells (DSSC) was successfully carried out. Theoretical study was carried out with the purpose to determine the effect modification of the addition of cyanoacrylic benzothiadiazole, cyanoacrylate, cyanovinyl, and cyanocynamic as electron acceptors to the characteristics of pelargonidin as dye DSSC. The effect of modification is based on the parameters of bond length, spectra, molecular electron density, light harvesting efficiency (LHE), (VRP), and HOMO-LUMO energy. The molecular structure created using the Avogadro program, then optimized by DFT/TDDFT method using a base set 6.311G *. Based on the results of research on pelargonidin-benzothiadiazole cyanoacrylate is a better modification when compared with pelargonidin without modification or pelargonidin modified with other cyano acids. This modification is better modification based on parameters molecular electron density, HOMO-LUMO energy, (VRP), bond lengths, and spectra. Pelargonidin-benzothiadiazole cyanoacrylic electron density in LUMO conditions centred in benzothiadiazole cyanoacrylic, HOMO and LUMO energy of dye is -4.97856 eV & -2,56731 eV, VRP value 0.439, bond lengths 1.936 Å, and spectra at wavelength 393.14 nm & 377.09 nm. Based on the light harvesting efficiency (LHE), pelargonidin without modification is the best modification with an LHE value 0.820.

Theoretical study of the use of cyano acid derivatives as electron acceptor groups in cyanidine as dye compounds of dye sensitized solar cells (DSSC) has been carried out based on energy parameters of HOMO-LUMO, LUMO electron localization, spectra, light absorption efficiency, coupling constants, and sensitizer bond length with TiO2. This study aims to determine the effect of cyanoacetic acid, cyanoacrylic benzothiadizole, cyanovinyl acid and cyanosynamic acid as electron acceptors on the photoelectric characteristics of cyanidine and determine the cyanoic acid derivative which can produce cyanidine photoelectric characteristics better based on energy parameters HOMO-LUMO, LUMO electron localization, spectra, light harvesting efficiency, coupling constant (VRP), and bond length of sensitizer with TiO2. This research begun with molecular optimization using DFT and TDDFT method with basis set of 6.311G *. HOMO-LUMO parameters used the same method with analysis technique using ECCE. The LUMO electron localization parameters use the same method, but the analysis technique used ECCE. Spectra using DFT method, using analytical technique using Chemcraft. Parameters of light absorption efficiency using DFT and TDDFT method with calculation technique using existing equations. Coupling constant parameters using the same method, the calculation technique used the energy equation of dye compounds were calculated in the conditions of HOMO, LUMO and TiO2 energy. Parameter length of the sensitizer bond with TiO2 were calculated used DFT method with avogadro analysis technique. Cyanidin cyanoacetate became the best modification based on HOMO LUMO energy parameter -4.569 and -1.01 eV, respesctively. In the electron localization parameter, the best modification was produced in cyanidine cyanoacetate with an electron-centered pattern on the cyanoacetic group. Spectra parameters produced the best modification, cyanoacetic cyanidine with a wavelength of 378.811 nm with osillator strength of 0.633. The light absorption efficiency parameters resulted in the best modification of cyanidin cyanoacetate with a value of 0.767. For parameter of clutch constant, best modification is cyanidin benzothiadizol sianoakrilik with a value -0.269. The best modification on the parameter length of the sensitizer bond with TiO2 was cyanidine cyanoacetate with a bond length of 1.926 Å.

Persaingan antara pelaku usaha yang semakin ketat akibat interaksi global menuntut setiap UKM (Usaha Kecil Menengah) sektor pangan harus lebih kreatif dan cermat dalam memasarkan produk mereka. Salah satu yang menjadi isu penting dalam persaingan global produk UKM sektor pangan adalah kenyamanan konsumen, khususnya konsumen muslim yang menuntut kehalalan suatu produk pangan. Oleh karena itu, pemerintah dan pihak terkait harus aktif memberikan penyuluhan terkait dengan sertifikat halal suatu produk. Jurusan Kimia UIN Sunan Kalijaga sebagai lembaga pendidikan tinggi yang core studinya fokus pada integrasi-interkoneksi sains-keislaman mewujudkan perannya dalam bentuk kegiatan penyuluhan proses sertifikasi halal hasil penyembelihan Rumah Potong Ayam (RPA) yang disampaikan kepada UKM anggota kelompok ternak unggas “Mitra Harapan Turi” di Dusun Garongan Wonokerto Turi Sleman Yogyakarta. Kegiatan ini merupakan langkah awal yang diikuti dengan kegiatan pendampingan, pembinaan, dan pengawasan bagi kelompok UKM tersebut guna meningkatkan pendapatan mereka. Materi penyuluhan meliputi manfaat dan proses sertifikasi halal suatu produk, khususnya produk RPA, serta materi mengenai teknik penyembelihan ayam potong yang sehat dan halal sesuai dengan syariat Islam. Peserta memperoleh pengetahuan baru dan motivasi dalam mengembangkan UKM mereka. Jika produk mereka dilengkapi dengan sertifikat halal, maka wilayah pemasaran produk mereka dapat diperluas hingga ke hotel dan rumah makan. Ini sangat memungkinkan karena Yogyakarta merupakan kota wisata yang memiliki banyak hotel dan rumah makan. Sebanyak 7 RPA bersedia mengurus sertifikat halal untuk produk mereka pada gelombang pertama bulan Maret 2015, sementara RPA yang lain menyusul pada gelombang kedua. Mereka didampingi oleh Jurusan Kimia UIN Sunan Kalijaga hingga memperoleh sertifikat tersebut dari LPPOM-MUI. Selanjutnya, Jurusan Kimia UIN Sunan Kalijaga bersama dengan LPPOM-MUI D.I. Yogyakarta akan melakukan pengawasan dalam pelaksanaan jaminan halal masing-masing RPA yang telah memiliki sertifikat halal.

Polymerization of purified eugenol from clove leaf oil using concentrated sulfuric acid as catalyst has been done in this research. Clove leaf oil was purified by vacuum redistillation, acid-base extraction, and vacuum fractionation to yield eugenol. The eugenol was polymerized with concentrated sulfuric acid in ratio 1: 2. Polyeugenol from eugenol of clove leaf oil resulted from redistillation, extraction, and fractionation is in solid form (yield: 88.14%); from redistillation and extraction is also in solid form (yield: 86.15%); from redistillation clove leaf oil is in gel form (yield: 100.29%). Structure of polyeugenol was determined by infrared spectrophotometer and characterized by thin layer chromatography (TLC). Molecular weight of the product was calculated by viscometry method. DOI: http://dx.doi.org/10.15408/jkv.v0i0.4685

The synthesis of chitosan–TiO2 film composite using sorbitol as plasticizer has been conducted. This research aims to develop environmental friendly plastic material which is safe for health due to the use of biodegradable chitosan - TiO2 that can block UV rays and therefore, maintain the quality of product from damage caused by UV rays. The anatase phase TiO2 nanocrystal was synthesized in chitosan matrix at room temperature and aging process. The solution was then added and blended in sorbitol for 24 hours to obtain homogeneous solution. The composite film was formed by coating method on a plate substrate, followed by drying. The characterization of film composite by XRD, TEM and FTIR showed the forming of anatase phase TiO2 nanocrystal that dispersed in chitosan matrix and formed the hydrogen bond. Meanwhile, from the physical properties characterization it was observed that the use of sorbitol as plasticizer had improved the plasticity tensile strength and elongation of the composite film. However, the excess sorbitol reduced the elasticity, tensile strength and elongation of the plastic. The best quality of plasticity obtained from film composite added by 3 % of sorbitol.