Synthesis,spectroscopic characterization,and thermal decomposition kinetics of some lanthanide（Ⅲ） nitrate complexes of 2-（N-o-hydroxyacetophenone） amino-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene

Complexes of La（Ⅲ）, Ce（Ⅲ）, Pr（Ⅲ）, Nd（Ⅲ）, Sm（Ⅲ）, Eu（Ⅲ）, Gd（Ⅲ）, Dy（Ⅲ）, Yb（Ⅲ）, and Lu0ID with 2-（N-o- hydroxyacetophenone）amino-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene （HAAT） formed by the condensation of o-hydroxyacetophenone and 2-amino-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene were synthesized and characterized on the basis of elemental analyses, molar conductance measurements, magnetic susceptibility data, UV-Visible, IR, and NMR spectral studies. The spectral data revealed that the ligand acted as a neutral tridentate coordinating to the metal ion through ONO donor sequence. A coordination number nine was proposed for the complexes. Thermal decomposition studies of the ligand and lanthanum（Ⅲ） complex were carried out and kinetic parameters were calculated using Coats-Redfem equation. The decomposition reactions followed random nucleation mechanism with one nucleus on each particle.     

Reduced graphene oxide wrapped sulfur nanocomposite as cathode material for lithium sulfur battery

Sulfur has been investigated as an active electrode material for secondary batteries due to theoretically specific capacity compared to the lithium-ion battery. In the present study, reduced graphene oxide (RGO) sheets wrapped Sulfur nanocomposite (S-RGO) synthesized by hydrothermal method and confirmed the wrapping of RGO sheets on Sulfur nanoparticles by various analytical techniques. The synthesized S-RGO nanocomposite demonstrated improved interaction of sulfur nanoparticles with RGO which is confirmed through XPS analysis. The synthesized S-RGO resulted in significantly improved reversible specific capacity and higher rate capability (823 mAh/g at 0.1C, 400 mAh/g at 1C) with 77 wt% of sulfur loading amount on the cathode of the Li–S battery. Therefore, the present study opens up new insights into sustainable development in the field of Li–S battery energy storage applications.     

Towards Probabilistic Formal Analysis of SATS-Simultaneously Moving Aircraft (SATS-SMA)

The objective of NASA’s Small Aircraft Transportation System (SATS) Concept of Operations (ConOps) is to facilitate high volume operation of advanced small aircraft operating in non-towered, non-radar airports. This system can provide improved and accessible air travel at a lower cost. Given the safety-critical nature of SATS, its analysis accuracy is extremely important. However, the commonly used analysis techniques, like pilot/computer simulation and traditional model checking, do not ascertain an error-free and complete verification of SATS due to the wide range of possibilities involved in SATS or the inability to capture the randomized and unpredictable aspects of the SATS ConOps environment in their models. Another limitation of these studies is that a limited speed range was used in the analysis. To overcome these limitations, we propose to formulate the SATS ConOps as a fully synchronous and probabilistic model, i.e., SATS-SMA, that supports simultaneously moving aircraft. The distinguishing features of our work include the preservation of safety of aircraft while providing a precise timing model, which is closer to reality compared to the previous hybrid analyses. Important insights related to the aircraft take-off and landing operations during the instrument meteorological conditions are also presented.     

Effects of high hydrostatic pressure on the mechanical behavior of a crystalline polymer–polyoxymethylene

The true stress-true strain behavior of polyoxymethylene, n(-CH₂O), as an example of a bulk semi-crystalline polymer, has been investigated for constant hydrostatic environmental pressures from 1 atmosphere to 8 kilobars with the principal objectives of elucidating the factors controlling flow and fracture. Experiments were conducted in uniaxial tension at room temperature and constant strain rate. The tensile observations were supplemented by measurements of bulk compressibility and stress relaxation behavior at pressure. In contrast with metals and inorganic compounds, the modulus, yield stress and fracture stress of POM increase strongly with pressure by a factor of approximately three at 8 kilobars. The modulus increase is shown from the stress relaxation measurements to be associated with a pressure-induced increase in the β-transition temperature which points to the potential usefulness of the concept of pressure-temperature super-position of mechanical behavior. The characteristics of the pressure dependence of the yield stress demonstrate that yield criteria based on continum mechanics considerations, including the Mohr or Coulomb-Navier criterion, are not valid for general deformation (non-plane strain) conditions in this polymer. The concept of a critical volume change determining the initiation of yielding is suggested to be applicable to semi-crystalline polymers. Comparison with analogous changes in yield stress with temperature points to an increasing contribution to the control of yielding by the initially disordered regions with increasing pressure or decreasing temperature. The fracture behavior observed at pressure eliminates the concepts of a critical stress as a fracture criterion for POM and of a simple reduction in normal stress at points of stress concentration as the principal effect of the applied pressure on fracture.     

L-Ornithine Monohydrochloride Doped Zinc Tris-Thiourea Sulphate Single Crystals for NLO Applications

Silicon - In the current study, transparent and bulk sized L-ornithine monohydrochloride (LOMHC) added zinc tris-thiourea sulphate (LOMHC-ZTS) single crystals are synthesized successfully by...     

Estimation of Uncertainty in the Calibration of Industrial Platinum Resistance Thermometers (IPRT) Using Monte Carlo Method

Monte Carlo method has been implemented for uncertainty estimation in IPRT calibration. The work is based on the Callendar van Dusen equation for 0–500 °C calibration range. Derivation of the mathematics model for running the simulation is also described. Results are compared with output from the traditional GUM method and we find close agreement between two methods.     

Performance evaluation of a curved electrode actuator fabricated without gold/chromium conductive layers

Microsystem Technologies - Curved electrode actuators displace on the order of a biological cell diameter at low actuation voltages, making them a potential candidate for probing and...