Lattice Model of Multilayer Adsorption of Particles with Orientation Dependent Interactions at Solid Surfaces

A simple lattice model has been used to study the formation of multilayer films by fluids with orientation-dependent interactions on solid surfaces. The particles, composed of two halves (A and B) were allowed to take on one of six different orientations. The interaction between a pair of differently oriented neighboring particles was assumed to depend on the degrees to which their A and B parts overlap. Here, we have assumed that the AA interaction was strongly attractive, the AB interaction was set to zero, while the BB interaction was varied between 0 and −1.0. The ground state properties of the model have been determined for the systems being in contact with non-selective and selective walls over the entire range of BB interaction energies between 0 and −1.0. It has been demonstrated that the structure of multilayer films depends on the strengths of surface potential felt by differently oriented particles and the interaction between the B halves of fluid particles. Finite temperature behavior has been studied by Monte Carlo simulation methods. It has been shown that the bulk phase phase diagram is qualitatively independent of the BB interaction energy, and has the swan neck shape, since the high stability of the dense ordered phase suppresses the possibility of the formation of disordered liquid-like phase. Only one class of non-uniform systems with the BB interaction set to zero has been considered. The results have been found to be consistent with the predictions stemming form the ground state considerations. In particular, we have found that a complete wetting occurs at any temperature, down to zero. Furthermore, the sequences of layering transitions, and the structure of multilayer films, have been found to be the same as observed in the ground state.

Development of nutritional meals and gruels from blends of pro-vitamin a cassava grits and African yam

The potentials of underutilized African yam bean (AYB) and pro-vitamin A cassava in the development of nutritious food products with acceptable sensory properties were studied. Grits were produced from freshly harvested yellow root pro-vitamin A cassava by peeling, washing, cutting, soaking, dewatering, roasting, sieving, and milling to obtain yellow root cassava grits while AYB flour was obtained by cleaning, roasting, dehulling, milling, and sieving (425 µm). A simple lattice design was used to obtain formulations of blends (100:0; 90:10; 80:20; 70:30; 60:40 and 0:100) of yellow root cassava grits and AYB flour. Gruels were prepared from these formulations using 4:5 w/v in boiling water while meals were prepared using 1:1 w/v of blend in boiling water for 5 min. Moisture, fat, ash, protein, crude fibre, carbohydrate, β-carotene and calorific content of the blends were in the ranges of 4.66 – 7.92%, 2.20 – 2.82%, 2.16 – 2.66%, 2.72 – 20.43%, 1.15 – 1.40%, 68.65 – 83.23%, 1.33 to 3.97 μg/g and 348.37 – 358.96 kcal/100 g, respectively. Saponin, tannin, trypsin inhibitor, hemagglutinin, starchyose, raffinose, phytate and Hydrogen Cyanide ranged from 0.039 – 0.087%, 0.11 – 0.15%, 1.24 – 3.15 mg/g, 1.47 – 3.49 mg/100 g, 1.51 – 1.81%, 0.38 – 0.45%, 0.82 – 2.69 mg/g, 0.07 – 4.47 mg/kg, respectively. The sensory evaluation revealed that the meal and the gruel samples had acceptable sensory attributes. The developed products have the potentials in alleviating the problem of protein malnutrition in developing countries.

Behavior of Ternary Mixtures of Hydrogen Bond Acceptors and Donors in Terms of Band Gap Energies

Three ternary mixtures composed by choline chloride (ChCl), ethylene glycol (EG), and a second hydrogen bond donor (HBD) as ethanol (A), 2-propanol (B), and glycerol (C) were studied in terms of composition related to the band gap energy (BGE). A Design of Experiments (DoE) approach, and in particular a Simple Lattice three-components design, was employed for determining the variation of the BGE upon the composition of each system. UV-VIS analysis and subsequent Tauc plot methodology provided the data requested from the DoE, and multivariate statistical analysis revealed a drop of the BGE in correspondence to specific binary compositions for systems A and B. In particular, a BGE of 3.85 eV was registered for the mixtures ChCl/EtOH (1:1) and ChCl/2-propanol (1:1), which represents one of the lowest values ever observed for these systems.

Behaviour of Ternary Mixtures of Hydrogen Bond Acceptors and Donors in Terms of Band Gap Energies

Three ternary mixtures composed by choline chloride (ChCl), ethylene glycol (EG) and a second hydrogen bond donor (HBD) as ethanol (A), 2-propanol (B), and glycerol (C) were studied in terms of composition related to the band gap energy (BGE). A Design of Experiments (DoE) approach, and in particular a Simple Lattice three-components design, was employed for determining the variation of the BGE upon the composition of each system. UV-VIS analysis and subsequent Tauc plot methodology provided the data requested from the DoE and multivariate statistical analysis revealed a drop of the BGE in correspondence to specific binary compositions for systems A and B. In particular, a BGE of 3.85 eV was registered for the mixtures ChCl/EtOH (1:1), and ChCl/2-propanol (1:1), which represents one of the lowest values ever observed for these systems.

Evaluasi Galur Harapan Padi Hitam (Oryza sativa L.) Berdaya Hasil Tinggi dan Berumur Genjah

Padi merupakan komoditas pangan penting dunia. Salah satu jenis padi adalah padi hitam yang saat ini belum banyak direkayasa, sehingga daya hasilnya rendah dengan umur yang panjang. Penelitian ini bertujuan mengetahui karakter agronomi galur harapan padi hitam berdaya hasil tinggi dan berumur genjah. Percobaan dilaksanakan di Pusat Inovasi Agro Teknologi (PIAT) Universitas Gadjah Mada di Kalitirto, Berbah, Kabupaten Sleman, Daerah Istimewa Yogyakarta pada bulan Maret-Agustus 2018. Bahan penelitian yang digunakan adalah 17 galur harapan padi dan 1 kultivar unggul lokal. Rancangan percobaan lapangan yang digunakan adalah Kisi Sederhana (Simple Lattice Design) dengan 3 ulangan. Setiap galur harapan ditanam pada plot berukuran 5x1,2 m dengan jarak tanam 20×30 cm, secara inling (1 bibit perlubang tanam) dengan umur pindah tanam 21 hari. Variabel pengamatan berupa komponen agronomi, komponen hasil dan karakter fisik gabah dan beras. Analisis varians dilakukan untuk variabel kuantitatif dengan taraf nyata α = 5%. dilanjutkan dengan uji Scott Knott. Hasil penelitian menunjukan karakter agronomi galur harapan padi hitam secara umum serupa dengan karakter agronomi galur harapan padi putih dan padi merah terkait dengan variabel tinggi tanaman sedang (lebih dari 110 cm), anakan produktif sedang (10-20 buah), umur panen sedang (125-150 HSS), panjang malai (20-30 cm), jumlah gabah per malai kurang dari 250 biji. Daya hasil galur harapan padi hitam P2 (4,10±0.27 ton/hektare) dan XI (3,95±0.45 ton/hektare) lebih tinggi dari varietas unggul lokal Sleman Merah (3,84±0.50 ton/hektare. Galur harapan padi hitam W (116±0.33 HSS) memiliki kategori umur panen genjah.

Uji Efek Antioksidan Formulasi Nanoemulsi Ekstrak Etanol Daun Parang Romang (Boehmeria virgata)

ABSTRAKUpaya menangkal terjadinya penyakit degeneratif akibat terakumulasi radikal bebas, salah satunya adalah pemanfaatan daun parang romang (Boehmeria virgata) yang memiliki potensi kandungan antioksidan yang diformulasikan dalam sediaan nanoemulsi. Tujuan dari penelitian ini mengetahui aktivitas antioksidan formulasi nanoemulsi ekstrak etanol daun parang romang. Daun Parang romang diekstraksi secara maserasi.selanjutnya diformulasi menjadi sediaan nanoemulsi dengan metode simple lattice design. Spektrofotometer UV-Vis digunakan untuk mengukur aktivitas antioksidan.. Hasil penelitian menunjukkan aktivitas antioksidan dengan metode DPPH pembanding kuersetin dan formulasi nanaoemulsi masing-masing diperoleh nilai IC50 yaitu 19,82 μg /mL dan 96,36 μg /ml. Hal ini menunjukkan bahwa formulasi nanoemulsi ekstrak daun parang romang memiliki aktivitas antioksidan yang kuat. Kata Kunci : Daun Parang romang, Nanoemulsi, Antioksidan, DPPH.

Simple Lattice Model of Self-Assembling Metal-Organic Layers of Pyridyl-Substituted Porphyrins and Copper on Au(111) Surface

A simple lattice model of metal-organic adsorption layers self-assembling on the Au(111) surface and based on pyridyl-substituted porphyrins differing by the number of functional groups and their position has been...

Geopolymerization of Coal Fly Ash, Ceramic Tile Waste and Spent Bleaching Earth for the Production of Sodium Aluminosilicate Monolith

In this study, compressive strength, density, porosity, and methylene blue adsorptive intensity of sodium aluminosilicate monolith produced from coal fly ash (CFA), ceramic tile waste (CTW), and spent bleaching earth (SBE) were evaluated. Using simple lattice mixture design, CFA-CTW-SBE blend with mass ratio of 55.95% CFA, 38.73% CTW, and 5.31% SBE, and an alkali solution containing 80% 8M NaOH and 20% sodium silicate, resulted to a maximum desirability of 12.4MPa compressive strength, 1310 kg/m3 density, 17.03% porosity, and 1.63% methylene blue adsorption intensity. The properties of the product conform to the specifications of ASTM C90-14 for lightweight load-bearing concrete.