Pestisida organik adalah pestisida yang bahan dasarnya berasal dari tumbuhan yang bersifat mudah terurai di alam. Salah satu tumbuhan yang dapat dijadikan bahan baku pembuatan pestisida organik adalah kulit jeruk nipis. Kulit jeruk dapat berpotensi menjadi repellent karena mengandung minyak atsiri dengan komponen limonene, mirsen, linalool, oktanal, decanal, sitronelol, neral, geraniol, valensen dan sinensial. Linalool, sitronelol dan geraniol termasuk senyawa yang bersifat repellent terhadap serangga (arthropoda).  Pengunaan bahan alami dari ekstrak kulit jeruk diharapkan lebih aman jika dibandingkan dengan bahan kimia Dichloro Diphenyl Trichloroethane (DDT). Proses pembuatan pestisida organik dilakukan dengan ekstraksi maserasi menggunakan ethanol sebagai pelarut. Dalam penelitian ini bertujuan untuk mengetahui pengaruh variabel terhadap hasil pengujian pestisida organic terhadap jangkrik. Hasil penelitian menunjukkan pada konsentrasi pestisida organic 5% didapatkan prosentase kematian jangkrik 72%, pada konsentrasi 15% didapatkan prosen kematian jangkrik 80%, dan pada konsentrasi 25% didapatkan prosen kematian jangkrik 88%. Hasil penelitian menunjukkan bahwa adanya pengaruh terhadap perbedaan konsentrasi pestisida organic terhadap kematian jangkrik. Kata kunci: jeruk nipis, maserasi, pestisida organik AbstractOrganic pesticides are pesticides whose basic ingredients come from plants that are easily biodegradable in nature. One of the plants that can be used as raw material for making organic pesticides is lime peel. Orange peel can potentially be a repellent because it contains essential oils with components of limonene, mirsen, linalool, octanal, decanal, citronellol, neral, geraniol, valensen and sinensial. Linalool, citronellol and geraniol are compounds that are repellent to insects (arthropoda). The use of natural ingredients from orange peel extract is expected to be safer when compared to the chemical Dichloro Diphenyl Trichloroethane (DDT). The process of making organic pesticides is done by maceration extraction using ethanol as a solvent. This study aims to determine the effect of variables on the results of testing organic pesticides on crickets. The results showed that at 5% organic pesticide concentration, 72% of crickets died, at 15%, 80% of crickets died, and at 25%, 88% of crickets died. The results showed that there was an effect on differences in the concentration of organic pesticides on the mortality of crickets.. Keywords: lime, maceration, organic pesticide

In this work, densities of dimethyl sulfoxide + 1-allyl-3-methylimidazolium chloride mixtures have been experimentally determined with a vibrating tube densimeter. Densities were measured at temperatures between 293.15 and 373.15 K and molar fractions of dimethyl sulfoxide xDMSO = 0, 0.05 0.1, 0.15, 0.25, 0.5, 0.75, 0.9 and 1 at pressures in the range P = [0.1, 35] MPa. It was found that density increases with ionic liquid concentration and with pressure and decrease with temperature. Excess molar volumes were calculated resulting in negative values with a maximum of non-ideality at DMSO concentration of xDMSO = 0.5. The excess molar values were less negative at high pressures. At T = 330 K a maximum in the excess molar values was observed at several concentrations. Density was correlated as a function of temperature, pressure and concentration with an average relative deviation of 0.12%.

In this work, densities of the systems dimethyl sulfoxide (DMSO) + choline acetate and DMSO + 1-ethyl-3-methylimidazolium acetate were measured with a Stabinger densimeter. The density was measured at temperatures T = [293.15, 373.15] K and for the full composition range when possible. Excess molar volumes and excess isobaric expansion coefficients were calculated for the latter system. The excess molar volume was correlated with the Redlich–Kister polynomial equation. Melting points of some mixtures of choline acetate + DMSO were also determined.

In this work, the Group Contribution Equation of State (GC-EoS) is extended to model two new ionic liquid families, namely, 1-alkyl-3-methylimidazolium dimethylphosphate ([-MeIm] + [Me2PO4]-) and 1-alkyl-3-methylimidazolium diethylphosphate ([-MeIm] + [Et2PO4]-). Pure group parameters for the functional groups [-MeIm] + [Me2PO4]-and [-MeIm] + [Et2PO4]and interaction parameters between these groups and the main paraffinic and aromatic subgroups (CH3, CH2, ACH, AC, ACCH3, CH2=CH) were estimated using infinite dilution activity coefficients data from literature. In order to evaluate the performance of the new parameters, the model was challenged against experimental data on phase behavior of binary mixtures, showing an average relative deviation of 4.5%.