Structural and Luminescence Studies on Barium Sodium Borosilicate Glasses Containing Uranium Oxides

Barium sodium borosilicate glasses containing different amounts of uranium oxides were prepared by conventional melt quench method and investigated for their structural aspects by ²⁹Si and ¹¹B MAS NMR technique combined with steady‐state luminescence and lifetime measurements. Based on MAS NMR studies, it is confirmed that uranium ions act as network modifier up to 15 wt% and beyond which a separate uranium containing phase is formed. From the luminescence studies, it is inferred that uranyl species is in a highly distorted environment. For more than 15 wt% uranium oxide incorporation, weaker U–O–U linkages are formed at the expense stronger U–O–Si/B linkages, as suggested by the excited state lifetime value of the uranyl species as well as red shift in emission peak maximum. For glass samples containing more than 25 wt% uranium oxides, crystalline barium uranium silicate gets phase separated from glass matrix as confirmed by XRD studies.     

Fabrication and Circuit Modeling of NMOS Inverter Based on Quantum Dot Gate Field-Effect Transistors

This paper presents the fabrication of a negative-channel metal–oxide–semiconductor (NMOS) inverter based on quantum dot gate field-effect transistors (QDG-FETs). A QDG-FET produces one intermediate state in its transfer characteristic. NMOS inverters based on a QDG-FET produce three states in their transfer characteristic. The generation of the third state in the inverter characteristic makes this a promising circuit element for multivalued logic implementation. A circuit simulation result based on the Berkley simulation (BSIM) circuit model of the QDG-FET is also presented in this paper, predicting the fabricated device characteristic.     

Non-dendritic Structural Changes in Al–7Si Alloy Cast Through Rapid Slurry Formation (RSF) Process

Rapid slurry formation (RSF) is a semi-solid metal forming technique, which is based on a so-called solid enthalpy exchange material. The beauty of the process is that the slurry is controlled by relative added amounts of the alloy system used. It is not necessary to accurately control the heat flux to surrounding media such as, crucible or mould. In the present investigation 15?% solid fraction in Al?C7Si alloy slurry has been produced by RSF method. The slurry so prepared was cast in gravity die cast mould with water cooling arrangement. Thus ingot of size 30?cm?×?5?cm?×?2.5?cm could be produced. The microstructure showed rosette and globular type ??-Al morphology. Tensile properties evaluated were higher than as cast Al?C7Si alloy. During slurry formation coarsening of particles was experimentally investigated and also theoretically described by Lifshitz-Slyozov-Wagner (LSW) theory and convective mass flow equations.     

A correlation study on the phenolic profiles and corrosion inhibition properties of mangrove tannins (Rhizophora apiculata) as affected by extraction solvents

The objective of this study was to investigate the correlation of phenolic compositions and corrosion inhibition properties of Rhizophora apiculata bark extracts as affected by nine solvent systems. Several phenolic compositions, namely, total phenolic content (TPC), total flavonoid content (TFC), condensed tannin content (CTC) were investigated. In addition, the inhibitive actions of tannin extracts on mild steel in 1 M HCl solution were studied by potentiodynamic polarization and electrochemical impedance spectroscopy. The results showed that extraction solvents had significant effects on TPC, TFC, CTC and inhibition properties of extracts. A correlation between CTC and inhibition properties of R. apiculata bark extracts was revealed.     

Characterisation of Seed Lipids from Bixa orellana and Trachyspermum copticum

Bixa orellana L. seeds possess a resinous lipid (6.3 %), which has a pungent and spicy odour. The seed is known for its medicinal properties such as anti‐inflammatory, antipyretic activity and as a cure for tonsilitis. Trachyspermum copticum L. seed is a well known digestive aid and relief from colic pain. T. copticum possesses essential oil rich in thymol (>50 %) and lipid (15.6 %). The present study was aimed to quantify lipid classes of these two species by silicic acid chromatography and analyze their fatty acid composition by gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS). It was observed that the seed lipids are rich in neutral lipids with 98.1 and 95.2 % and lower quantities of glycolipids of 1.5 and 3.8 % and phospholipids of 0.36 and 1.0 % in B. orellana and T. copticum, respectively. The fatty acid composition of B. orellana seed lipid showed major quantities of palmitic (26.9 %), linoleic (26.1 %), oleic (17.5 %), linolenic (15.1 %), stearic acid (10.8 %) and small quantities of eicosanoic acid (3.6 %). In T. copticum seed lipids, petroselinic acid (68.3 %) and linoleic acid (25.3 %) together constituted 93 % of the total lipid. The results revealed that the lipids after recovery of the essential components namely, bixin and volatile oil from B. orellana and T. copticum, respectively can be further explored for industrial applications.     

Solubility and dissolution enhancement strategies: current understanding and recent trends

Identification of lead compounds with higher molecular weight and lower aqueous solubility has become increasingly prevalent with the advent of high throughput screening. Poor aqueous solubility of these lipophilic compounds can drastically affect the dissolution rate and subsequently the drug absorbed in the systemic circulation, imposing a significant burden of time and money during drug development process. Various pre-formulation and formulation strategies have been applied in the past that can improve the aqueous solubility of lipophilic compounds by manipulating either the crystal lattice properties or the activity coefficient of a solute in solution or both, if possible. However, despite various strategies available in the armor of formulation scientist, solubility issue still remains an overriding problem in the drug development process. It is perhaps due to the insufficient conceptual understanding of solubility and dissolution phenomenon that hinders the judgment in selecting suitable strategy for improving aqueous solubility and/or dissolution rate. This article, therefore, focuses on (i) revisiting the theoretical and mathematical concepts associated with solubility and dissolution, (ii) their application in making rationale decision for selecting suitable pre-formulation and formulation strategies and (iii) the relevant research performed in this field in past decade.     

Humble,humane and harmonious houses of Laurie Baker

Laurie Baker (1917–2007) was an architect from Birmingham, who settled and worked in India, where he met and was profoundly influenced by Gandhi. In India, he developed simple and indigenous principles of design of houses, which are comfortable and affordable by the poor. Laurie Baker is often called the Mahatma Gandhi of domestic architecture. His work is truly sustainable architecture – ecological, economic and social.     

Gonflement de la chaux dans les briques

Le problème de l'éclatement des briques dû à l'action de la chaux devient grave dans la fabrication des briques en différents endroits de l'lnde et d'ailleurs. Des briques cuites tombent en poussière lorsqu'elles sont exposées à l'air libre, du fait de la présence de particules de chaux. L'Institut central de recherche de la construction de Roorkee s'est attachée à l'étude du mécanisme par lequel les chlorures peuvent prévenir cet inconvénient.     

Easy,operable ionic polymer metal composite actuator based on a platinum‐coated sulfonated poly(vinyl alcohol)–polyaniline composite membrane

In this study, an electric‐stimulus‐responsive bending actuator based on a platinum (Pt)‐coated sulfonated poly(vinyl alcohol) (SPVA)–polyaniline (PANI) composite membrane was developed. The SPVA–PANI membrane was prepared by a solution casting method; it showed good electrochemical properties and an adequate ion‐exchange capacity of 1.6 mequiv/g of dry membrane. The water uptake by the membrane with 4 h of immersion time at 45 °C was found to be 425%. The SPVA–PANI composite membrane based ionic polymer metal composite (IPMC) actuator prepared by the coating of Pt metal layers on both sides of the membrane by an electroless plating process showed a good proton conductivity of 1.75 × 10^?3 S/cm. The smooth and uniform coating of Pt on both surfaces of the membrane, as indicated by scanning electron micrographs, seemed to be responsible for the slow water loss that is necessary for the long life of an IPMC actuator. The maximum water loss was 48% at 6 V for 12 min. This indicated the better performance of the IPMC membrane when an electric potential was applied. According to electromechanical characterization, the maximum tip displacement was 14.5 mm at 5.25 V. A multifinger IPMC membrane based microgripping system was developed, and it showed potential for microrobotics application. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43787.