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The electrical properties of graphene doped with graphite and N-pyridine and their interaction with K+ ions have been studied using the density-functional based tight-binding (DFTB) method. Pure graphene and graphene with a single vacancy are used as comparisons. A 4 × 4 × 1 unit cell was used as the base, while an enlarged supercell consisting of primitive unit cells repeated to 40 × 40 × 1 was used for sampling. The structure and the Fermi Level of the optimized graphene agreed with the experimental data. The presence of N as a dopant in a graphitic configuration shifted the Fermi level to higher levels, while N in a pyridinic configuration shifted it to lower. Both showed an increase in the intensity of electronic activity. The presence of the dopant N resulted in the widening of the bandgap in graphene. The electrical characteristics of the examined graphenes influence the strength of the interaction with K+ ions.

The properties of three types of CoMo/USY catalysts with different synthesized methods have been studied. The sequential and co-impregnation methods followed by activation using calcination and reduction process have been conducted. The properties of the catalysts were examined using Fourier-transform-infrared (FTIR) spectroscopy, X-ray diffraction (XRD) with refinement, and surface area analyzer (SAA). The FTIR spectrum study revealed the enhanced intensity of its Bronsted acid site, and the XRD diffractogram pattern verified the composition of pure metals, oxides, and alloys in the catalyst. The SAA demonstrated the mesoporous features of the catalyst. Scanning electron microscopy showed an irregular particle morphology. Additional analysis using the transmission electron microscopy indicated that the metal has successfully impregnated without damaging the USY structure.

The lability, dynamics of the first solvation shell, and structure breaking effect properties of Cs+ in liquid ammonia have been evaluated using Quantum Mechanical Charge Field Molecular Dynamics (...

Defects in graphene alter its structure, electrical characteristics, and interaction with K+ ions. The related characteristics of divacancy defect graphene and N, S codoped divacancy graphene were effectively explored using the DFTB technique. Divacancy is essential for the band gap opening. The dopants considerably enhance the density of state (DOS) intensity and alter the graphene-character bands. The depletion of density caused by the dopant is seen on the charge density isosurface. Because the charge of the K+ ion is balanced by the dopant, the ion prefers to be adsorbed on divacancy graphene with dopants.

The synthesis of CoMo/Mordenite (CoMo/MOR) catalysts was conducted using a co-impregnation method at a various Co/Mo ratios. The produced catalysts were then characterized by X-ray diffraction, total acidity analysis, and scanning electron microscopy. The activity of the catalyst in a hydrotreatment reaction was evaluated by applying the catalyst as a reduced-catalyst to the hydrocracking (HC) reaction of anisole molecules. Analysis of the diffraction data using the Le Bail refinement technique showed that the metal phase was successfully impregnated into the MOR. In addition, increasing the metal content resulted in an increase in the acidity of the catalysts and changed the morphology of the catalysts from homogeneous to heterogeneous with larger particle size. According to the data of GCMS, it is known that the catalysts successfully removed methyl group of anisole molecules. Hydrotreatment reaction with the prepared-catalyst produced 4.77% of phenols. It is 122 % higher than the reaction with MOR catalyst.

Structural and dynamical properties of Cu+ in 18.6% aqueous ammonia solution at 298.15 K have been investigated via quantum mechanical charge field molecular dynamics (QMCF MD). The QM region was set to a radius of 6.7 A to include the first and second solvation shell. The Hartree-Fock (HF) level was applied to calculate the ion-ligand and ligand-ligand interactions in the QM region using the LANL2DZ-ECP basis set for the ion and DZP-Dunning for the ligands. The Cu+ N and Cu+ O radial distribution functions showed maximum first shell probabilities at distances of 2.23 and 2.30 A, respectively. Predominantly, four NH3 molecules were found to form a tetrahedral [Cu(NH3)4]+ complex, although the formation of a short-lived intermediate [Cu(NH3)3H2O]+ complex was also observed. The mean residence times of NH3 and H2O ligands in the first solvation shell were estimated as 14.6 ps and 1.3 ps, respectively, reflecting the strong interaction between Cu+ and ammonia as well as the occurrence of rapid water exchange. The vibrational power spectrum of the Cu+ N vibration in the first solvation shell revealed a wave number of 252 cm−1 with a corresponding force constant of 43.0 Nm−1. In addition, an NBO analysis was carried out, confirming the strong electrostatic character of the Cu+ NH3 and Cu+ H2O interaction, and highlighting that the presence of H2O ligands may destabilize the first solvation shell.

At the factory of CV. Solo Button, coconut shell charcoal is made by heating the raw material in the open concrete reactor. This simple process results in minimal surface area characteristics and pore size, so the chrocoal is less suitable for the use as an adsorbent. Addition of treatment with degassing using N 2 at temperatures of 200 o C and 300 o C can increase surface area, pore size and number of pore charcoal. The SAA and BET analysis showed an increase in surface area of 6.2% and 93.6% as well as an increased pore size of 14.5% and 12.29% at both temperatures. Adsorption-desorption graphs indicate that the untreated charcoal has uneven surfaces and the pores are not detected while the degassing treatment at these temperatures indicates the formation of micropores from the charcoal. Keywords: chrocoal, pore, surface area, coconut shell

School buildings are important for the education process. Surabaya, the second-largest city in Indonesia has many public-school buildings. As the buildings have a long project life cycle, the concept of sustainable development is relevant for this type of facility with regard to promote maximum benefit to the community. This paper aims to determine the criteria of social sustainability for the public-school buildings in Surabaya. The study first identified the variables based on literature. Then, a preliminary survey involving four experts was conducted to verify which variables should be used for the questionnaire survey. The variables were also analyzed using mean and standard deviation (SD). The study found 17 relevant indicators for measuring the social sustainability of school buildings in Surabaya. The five most relevant indicators are (1) the building is supported by users and the community; (2) the building is close to public transportation facilities; (3) the building can fulfill the needs of the local community; (4) the building can adapt to changes; and (5) the building is accessiblefor all people. The implementation of social aspects in construction projects is expected to deliver not only short-term, but also long-term project benefits to the community, as this aspect is closely related to community interests.

The school building has an important role in the education process of the young generation. Surabaya as the second biggest city in Indonesia has a quite large number of school buildings. As a building is a construction project, it has a long project life cycle, it is very important to adopt a sustainable development concept to provide maximum benefit to the community. Social sustainability is one of the sustainable development aspects and has a close relationship with the community needs and interests. This aspect is essential to promote project benefit streams to the community not only in the short-term but also in the long-term. This research is an initial research step to investigate social sustainability criteria in public school buildings in Surabaya. Data was collected through a series of research steps consisting of a preliminary survey, pilot test, and questionnaire distribution. Mean analysis was used to rank the attributes criteria according to the three stakeholders’ perceptions. Finally, seventeen attributes were considered relevant to this research. This study provides a reference for the designer as well as the decision-maker such as the government on how to achieve social sustainable public buildings.

Rb(I) ion solvation in liquid ammonia has been studied by an ab initio quantum mechanical charge field molecular dynamics simulation, and the first solvation shell structure has been analyzed using natural bond orbital. The simulation was performed for an ion and 593 ammonia molecules in a box with a length of 29.03 A corresponding to a liquid ammonia density of 0.69 g/mL at 235.16 K. The quantum mechanical calculation was carried out for atomic interactions in the radius of 6.4 A from the ion using LANL2DZ ECP and DZP (Dunning) basis sets for Rb(I) ion and ammonia respectively. The trajectories of the simulation were analyzed in terms of radial, angular, and coordination number distribution functions, vibration, and mean residence time (MRT). Two solvation shell regions are observed for the Rb(I)-N as well as the Rb(I)-H. The maximum distance of Rb(I)-N in the first solvation shell is in accordance with experimental data where a coordination number of 8 is favorable. A non-single coordination number of the first and second shell indicates dynamic solvation structure. It is confirmed by frequent exchange ligand processes observed within a simulation time of 15 ps. The low stabilization energy of donor acceptor ion-ligand interaction with a small Wiberg bond index affirms that the Rb(I)-NH3 interaction is weak electrostatically.

Petani pembesaran lele banyak yang mengeluh gagal dalam usahapembesaran lele. Kegagalan tersebut disebabkan oleh penggunaan pakandan kolam yang tidak efisien serta harga pakan mahal. Tujuan kegiatanpengabdian masyarakat ini memberikan wawasan tentang metode barudalam usaha pembesaran lele yang menguntungkan. Mitra pengabdiankegiatan ini yaitu kelompok pembesaran lele Sungut Emas di Boyolali danpetani-petani pembesaran lele disekitarnya. Metode pengabdiandilakukan dengan metode substitusi ipteks secara teori, praktek lapangan,dan pendampingan. Substitusi ipteks secara teori meliputi penjelasantentang pembesaran lele tebar padat dan aplikasi enzim dalam efisiensipakan. Materi praktek lapangan meliputi cara persiapan air, carapengelolaan air, cara menangani penyakit dan cara memberi pakan.Simpulan, substitusi ipteks pembesaran lele tebar padat mampumenyelesaikan masalah yang dihadapi petani pembesaran lele tebar padatsehingga keuntungan usaha meningkat.

Ab initio of Quantum Mechanics Charge Field Molecular Dynamic (QMCF-MD) of K(I) ion in liquid ammonia has been studied. A Hartree-Fock level of theory was coupled with LANL2DZ ECP basis set for K(I) ion and DZP (Dunning) for ammonia. Two regions as first and second solvation shell were observed. In the first solvation shell at distance 3.7 (A), K(I) ion was coordinated by four to eight ammonia molecules dominated by K(NH 3 ) 6 + species. Second shell of solvation was ranging between 3.7 A to 7.3 A. Within simulation time of 20 ps, the frequent exchange processes of ligands indicating for a very labile solvation structure. Four mechanism types of ligand exchange between first and second solvation shell were observed. Mean residence time of ligand is less than 2 ps confirming weak in ion-ligand interaction. Evaluation of K(NH 3 ) 6 + using natural bond orbital analysis shows that the Wiberg bond Index is less than 0.05 indicating weak electrostatic interaction of K-N.

The Freundlich adsorption isotherm is mostly presented as an empirical equation and the (fractal) Langmuir adsorption isotherm is derived from kinetics. However, their constants are determined by thermodynamic approach. As yet, both are used as an independent tool for determining the type of adsorption, just physical or chemical adsorption. This study aims to introduce an alternative way of driving Freundlich adsorption isotherm from kinetics, to elaborate its relation with the (fractal) Langmuir adsorption isotherm, and to determine their constants simultaneously by kinetics approach. An alternative way of determining the constants in both isotherm equations by kinetics approach was introduced. The results were then compared with that obtained by the conventional method. The study is theoretical but the validity of determination technique is based on the statistical tests on data adapted from literature. The Freundlich adsorption isotherm is introduced; the isotherm is the (fractal) Langmuir adsorption isotherm at relatively low concentration. It is irrelevant to use both adsorption isotherm separately. The new method is more reliable and its represent the reaction.

Penelitian ini bertujuan untuk mengetahui pengaruh katalis Mo-Co/USY terhadap distribusi dan konversi produk serta pengaruh penambahan logam Co terhadap selektivitas produk benzena pada reaksi hidrodeoksigenasi (HDO) anisol. Reaksi HDO anisol dilakukan dengan sistem alir. Produk yang terbentuk dianalisis dengan kromatografi gas-spektrometer massa GC-MS. Produk utama dari HDO anisol yaitu benzena dan toluene. Aktivitas katalis Mo- Co/USY lebih tinggi daripada USY dan termal. Katalis Mo-Co/USY B memiliki selektivitas tertinggi pada produk benzena (15%).Kata kunci: aktivitas katalis, hidrodeoksigenasi, katalis Mo-Co/USY, reaksi hidrodeoksi- genasi anisol

The non-sulfide catalysts Co-Mo/USY were prepared with three different methods, i.e. co-impregnation and two sequential impregnation procedures. The phases of the synthesized materials and their composition were characterized with X-ray diffraction. Furthermore, the X-ray diffraction patterns were analyzed using Le Bail methods with Rietica software. Finally, an overview of the substitution effect of cobalt and molybdenum on the metal content and acidity of the catalyst were also investigated.

The preparation and characterization of bimetallic catalysts using impregnation method with a variation of concentration of precursor sequence Co and Mo metal obtained catalyst K 1 [Co (0.018 M) - Mo (0.037 M)/USY]. K 2 [Co (0.026 M) - Mo (0.055 M)/USY], K 3 [Co (0.035 M) - Mo (0.074 M)/USY], K 4 [Co (0.05 M) - Mo (0.11 M )/USY] and K 5 [Co (0.107 M) - Mo (0.22 M)/USY].Character of the catalyst in terms of crystallinity was analyzed by XRD. The result shows that there is no cristalinity damage of USY after impregnation but the amorphous cristalin structure was obtained. Amount of metal content was analyzed by XRF and the catalyst morphology by SEM-EDS. The result shows that the higher the concentration of Co and Mo so that find the higher content of metal in catalyst of the prepared catalyst increase. K 4 shows the best characteristic of catalysts prepared in this research. Analysis of K 4 is proving that Co and Mo are presented in catalyst

Research on the preparation and characterization of sulfonated polystyrene (PST) /chitosan vanillin (KV) composite as electrolyte membranes has been conducted in order to investigate the effect of PST and KV composition to its chemical and physical properties. Polystyrene was modified by sulfonation reaction to produces PST, meanwhile chitosan was modified by schift base reaction to produces KV. The composite membranes were prepared by casting method and were characterized in order to identify the functional groups contained in the composite, the cation exchange capacity (CEC), the Swelling Degree (SD), the thermal properties and the morphology. The peak of imine vibration in the FTIR spectrum indicates that the chitosan vanilin was succesfully synthesized. Meanwhile, the peak of sulfonate vibration indicates the product of sulfonation on polystyrene. The result of CEC analysis shows that the addition of sulfonate groups on polystyrene and the addition of phenolic groups on chitosan increase the CEC value. The increasing of PST and KV concentration in membrane enhance the CEC value. However, the increasing of PST concentration in membrane composition even decrease the Swelling Degree of membranes. Meanwhile, the increasing of KV concentration increase the swelling degree of membranes. Thermal analysis shows that the thermal decomposition of membranes occurs in three stages i.e. the dehydration of water molecules, the degradation of the subtituen groups and the plasticizer and the degradation of the back bone of chitosan and polystyrene.

Effect of temperature variation to product distribution, rate and deactivation of catalyst of tetrahydrifuran hydrodeoxygenation have been conducted using Pt/gAl2O3 with aluminum enrichmen. Reaction was conducted by flow system. Product of reaction were analyzed as propane (C3) and buthene derivate (C4). At 350ºC, reaction product and rate constant were optimum. At higher temperature, product distribution was shift from C4 to C3. Lowering pore size catalyst, surface area and acidity of catalyst were responsible to catalyst deactivation. Deactivation process was follow exponential regression.

Ca-Mg-Al Layered Double Hydroxides (Ca-Mg-Al-LDH) compounds were successfully synthesized from brine water and AlCl3.6H2O as the starting materials by coprecipitation method. The product result was characterized by X-ray powder diffraction (XRD) and Fourier transform infrared (FT-IR). The effects of the reaction time and the molar ratios of the raw material on the crystallinity of Ca-Mg-Al-LDH were examining. Results show that increasing reaction time (30; 60 and 90 min.) could improve the crystallinity and monodispersity of layered double hydroxide compounds particles. The well-defined Ca-Mg- Al-LDH could be prepared with (Ca+Mg)/Al molar ratios 0.5.

Langmuir adsorption isotherm equation is generally derived using the kinetics approach and based on some assumptions. These assumptions are usually not accompanied by an adequate explanation related with the mechanisms and the determination techniques of its adsorption constants. This study presents a simple technique on the determination of the isotherm equation based on the main assumption so called the monolayer assumption. Furthermore, a more precise technique for determining the adsorption constants is also described. This theoretical study is supported with statistical analysis on the experimental data adapted from the literature. Two theories based on adsorption mechanism and based on rate were introduced. Regardless of its limitations, the results show that the technique for the determination is valid.

The effect of adsorbate concentration, surface tension and temperature on glycerol adsorption over activated carbon have been conducted. Activity of adsorbent was increased by soaking activated carbon in H2SO4 10% solution for 12 hours followed heating at a temperature of 500oC under N2 gas flow for 3 hours. Furthermore, the identification and characterization of activated carbon were done by infrared spectroscopy (IR)   and gravimetric method acidity test. Conditions of adsorption of glycerol by activated carbon were carried out using batch method with ±12 hours of contact time on the variation of adsorbate concentration or the ratio glycerol : water (v/v) 1 : 2, 1 : 3, 1 : 4, and 1 : 5, as well as variations in 30, 40, 50, and 60 oC. The result showed that increased activity of activated carbon increased acidity from 0.5 mmol/gram to 2.7 mmol/gram. Increasing concentration of glycerol causes the surface tension decreases and (∂I³/∂C) becomes negative with means that glycerol was adsorbed over the surface. It has been confirmed by the increase of actvated carbon capacity is proportional to the increased concentration of glycerol. Temperature was also playing the role of glycerol adsorption where at 60 oC maximum adsorption was riched.   Keywords: Adsorption, Glycerol, Adsorbate concentration, Temperature, Surface tension, Activated Carbon