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"The measurement of specific surface area of porous materials has long been important in physical sciences and is currently growing in importance in applied and environmental science. Numerous systems have been developed for surface area measurement by gas adsorption. Commercial systems are available which can measure a wide range of absolute surface area with relative ease. However, their cost is often prohibitive. In this study, an inexpensive apparatus for surface area measurement has been set up to be used for measuring supercritical adsorption of CO2. The Ono-KondoLattice model was used to represent the adsorption isotherm and to determine the surface area. The results of surface area determination using CO2 adsorption combined with OK model have been compared to the numbers obtained from nitrogen BET method. For surface area determination of zeolites and activated carbons, the new methodgive reasonable agreement results (within 10% deviation) compared to the results obtained from nitrogen BET method. In addition, thenew method also gives more reasonable results for surface area determination of coals. As known, the nitrogen BET method gives almost zero of coals? surface area. This might due to the characteristic of the coals? structure that might be change (the pores are closed) during the cooling process in nitrogen BET method. Moreover, the new method can also be used to determine the surface area of porous materials using CO2 adsorption data at various temperatures without sacrificing their accuracy."

"Andrografolida merupakan senyawa yang terkandung dalam tanaman sambiloto (Andrographis paniculata) yang memiliki khasiat sebagai anti-infeksi. Sistem penghantaran yang umum digunakan untuk zat ini adalah oral, namun sistem penghantaran ini memiliki beberapa kekurangan. Transfersom dipilih untuk mengatasi beberapa kekurangan tersebut. Penelitian ini bertujuan untuk mendapatkan formula transfersom andrografolida yang optimal menggunakan metode respon permukaan (Response Surface Methodology, RSM). Pada penelitian ini digunakan desain eksperimen full factorial dengan dua faktor yaitu perbandingan zat aktif terhadap total lipid dan perbandingan jumlah surfaktan terhadap fosfolipid, sehingga diperoleh 9 variasi formula. Optimasi formula dilakukan dengan Design Expert 12.0.1.0. Dari hasil optimisasi didapatkan bahwa formula optimal adalah pada rasio konsentrasi zat aktif terhadap total lipid 1:10, dan rasio perbandingan konsentrasi surfaktan terhadap fosfolipid 25:75 dengan ukuran partikel 206,22 nm, potensial zeta -40,80 mV, indeks deformabiltas 2,32 dan efisiensi penjerapan 92,20%, dengan nilai desirability 0,87. Namun, metode ini hanya mampu memprediksi pengujian berikutnya untuk respon potensial zeta dan indeks deformabilitas. Metode ini dapat digunakan untuk lebih mengoptimalkan formula transfersom secara keseluruhan dengan menambahkan jumlah variabel.

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Andrographolide is a component of the Sambiloto/Bitter plant (Andrographis paniculata) which has anti-infective properties. The delivery system commonly used for this substance is oral, but this delivery system has several drawbacks. Transfersomes were chosen to overcome some of these drawbacks. This study aims to obtain the optimal andrographolide transfersome formula using the Response Surface Methodology (RSM). In this study, the experiment was designed by full factorial with two influence factors, which were the ratio of the surfactant to phospholipid, and the ratio of total lipid to active ingredient, hence there were 9 transfersome formulas. Response surface and optimization was accomplished by Design Expert 12.0.1.0. The RSM optimization showed that the optimal formula of the andrographolide transfersome had the andrographolide to total lipid ratio of 1 to 10, and the surfactant to phospholipid ratio of 25:75 with a particle size of 206.22 nm, zeta potential. -40.80 mV, deformability index 2.32, and entrapment efficiency 92.20 %, with a desirability value of 0.87. However, this method can predict the next test for zeta potential and deformability indeks only. This method can be used to further optimize the overall transfersome formula by including more variables."

"Adsorpsi merupakan salah satu metoda yang dapat digunakan untuk menangani masalah limbah emulsi minyak solar.Pada penelitian ini digunakan adsorben admisel zeolit HDTMA-Br teradsolubilisasi polimetil metakrilat (PMMA) untuk demulsifikasi dan adsorpsi solar. Kondisi optimum pembuatan model limbah emulsi solar adalah konsentrasi SDS 0,002 M, perbandingan minyak : air yaitu 5x10-4:1, kecepatan pengadukan 450 rpm selama 15 menit. Hasil uji kestabilan emulsi minyak dalam air dengan turbidimeter didapatkan nilai turbiditas 388 NTU dan uji ukuran partikel dengan PSA didapatkan 337,9 nm. Pembuatan adsorben zeolit admisel-PMMA dilakukan dengan melalui tahapan: adsorpsi surfaktan HDTMA-Br pada permukaan zeolit membentuk admisel, mengadsolubilisasikan monomer metil metakrilat (MMA) ke dalam admisel dan polimerisasi MMA dengan menambahkan inisiator kalium persulfat (K2S2O8). Keberhasilan pembentukan zeolit admisel-PMMA tersebut dibuktikan dengan spektrofotometer FTIR. Analisis kuantitatif adsorpsi minyak solar oleh zeolit admisel-PMMA digunakan metode ekstraksi gravimetri dan adsorpsi SDS menggunakan spektrofotometer UV-Vis. Kondisi optimum adsorpsi adalah massa adsorben 0,6 gram, waktu pengadukan 45 menit dan pH 7,3. Kapasitas adsorpsi optimum untuk solar adalah 97,46 mg/gram dan untuk SDS 16,52 x 10-4 mmol/L.

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Adsorption and demulsification is the one solution to handle waste diesel oil emulsion. Therefore, in this research, applications of zeolite admicelle HDTMA - Br adsolubilized polymethyl methacrylate (PMMA) for demulsification and adsorption waste of diesel oil emulsion. The optimum condition of fuel emulsion waste includeof SDS concentration of 0.002 M, the variation ratio of oil:water is 5x10- 4:1, stirring 450 rpm for 15 minute. Result of stabilized emulsion with turbidimeter is 388 NTU as amount of turbidity and 337,9 nm of particle test with PSA. Making adsorption zeolite admicelle-PMMA through the stages of HDTMA-Br surfactant adsorption on the surface of the zeolite, adsolubilized methyl methacrylate monomer into the zeolite admicelle and polymerization initiator admicelle by adding calium persulfate (K2S2O8).The success of the modifications proved by FTIR spectrophotometer showed that the spectrum of PMMA has appeared on zeolite admicelle-PMMA. The efficiency of zeolite admicelle PMMA forming was proven by FTIR spectrophotometer. On the other hand, quantitative analysis of fuel emulsion adsorption by zeolit was using gravimeter extraction method while SDS adsorption was using UV-Vis spectrophotometer. The optimum condition of adsorption are 0,6 gram adsorbent mass, 45 minutes agitation time and pH 7,3. Optimum adsorption capacity of fuel is 97,46 mg/gram and 16,52 x 10-4 mmol/L for SDS."