Ilmenite phase nickel titanate nanowhiskers as highly sensitive LPG sensor at room temperature

The NiTiO₃ nanoparticles with ilmenite phase were synthesized by the sol gel method and investigated for sensing of various volatile organic compounds. The resistive type sensing by NiTiO₃ towards LPG was not reported earlier where the sensor showed fair response towards hydrogen sulfide gas, but the sensitivity towards LPG was very high. The response % for 150 ppm of LPG was approximately 3200% at room temperature. The high response towards LPG was due to the presence of some amount of rutile TiO₂ in the composites. The response and recovery times of these sensors were very less (about 2 s) which could be attributed to the whiskers like structure of NiTiO₃.     

Application of Theory of Constraints in an integrated poultry industry

Theory of Constraints developed by E. M. Goldratt was initially applied to production scheduling and later to various areas such as Operations, Finance and Measures, Project Management, Marketing, Sales, Managing People, Strategy and Tactics. However, these applications were in engineering industries and products. The Strategic Thinking Processes of Theory of Constraints are designed to help combat an enormous problem faced by organizations--the tendency of organizations and their management to study, construct and implement solutions in isolation. In this case study, we applied the Theory of Constraints' Strategic Thinking Process in one of the leading integrated poultry businesses in India to identify and overcome the policy constraints in the business. After overcoming the policy constraints, overwhelming improvements in throughput and Inventories were observed.     

Synthesis of flexible polymeric shielding materials for soft gamma rays: Physicomechanical and attenuation characteristics of radiation crosslinked polydimethylsiloxane/Bi2O3 composites

Flexible lead‐free high energy radiation shielding material was developed through internal compounding. Polymer‐filler interaction, crosslinking density, specific gravity, physicomechanical characteristics, percentage attenuation, and thermal stability of the crosslinked composites were estimated. It was found that even at very high filler loading composites can be crosslinked; however, the crosslinking density was composition dependent and was highest in 10–50 wt% loading range at 100 kGy and 200 kGy. The Nielsen model was applied to understand the micromechanics of the system. Attenuation of gamma radiation from Am241 was not affected by the crosslinking density. Thermal stability of the composites was found to be significantly affected with bismuth oxide loading. POLYM. COMPOS., 37:756–762, 2016. © 2014 Society of Plastics Engineers     

Heterogenized copper catalysts for the amination of arylhalide: Synthesis,characterization and catalytic applications

This research investigated the synthesis, characterization and catalytic activity of heterogenized copper complexes for the selective amination of aryl halides. Amination reactions using homogeneous copper catalyst systems are not generally selective and it is also difficult to recover the catalyst from the homogeneous system for recycling. To overcome these difficulties, our efforts were directed towards the development of cheaper heterogeneous catalyst systems, which can be easily recovered and recycled. Heterogenized analogs of the homogenous Cu complexes were prepared using two methods: (a) encapsulation of copper complexes in zeolite-Y and (b) tethering of copper complexes on various supports like zeolite-Y, silica, charcoal, or clay. The encapsulated and tethered copper catalysts on zeolite-Y were characterized using EPR, Diffused reflectance UV–vis, XRD, IAS, ICPES, SEM, and TEM. The results confirmed that the copper complexes were truly heterogenized in zeolite-Y support. Encapsulated and tethered copper complexes were tested for amination of aryl iodide. The effects of various reaction parameters were examined using tethered Cu(Phen)(PPh₃)Br-PTA-Y catalyst to determine optimum conditions. A recycle study of encapsulated and tethered Cu catalyst was carried out to test their robustness for possible commercial exploitation.     

Computational study of 5<Emphasis Type="Italic">d</Emphasis> transition metal mononitrides and monoborides using density functional method

5d-metal mononitrides and monoborides viz. X-N and X-B (X = La, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg) are studied using density functional method based B3LYP functional with LANL2DZ and SDD basis set. The lowest spin state, electron affinities, ionization potentials and binding energies for mononitrides and monoborides are obtained. The electronic state and electronic configuration of mononitrides and monoborides are discussed. Orbitals involved in bond formation are identified. The properties of mononitrides and monoborides are compared. It is found that 5d-metal atoms form stronger bond with nitrogen atom than the boron atom. The range of binding energy, electron affinity and ionization potential is wider for mononitrides than that for monoborides. The properties of 5d-metal mononitrides and 3d-metal mononitrides are also compared. The binding energies for the former are lower than those for the latter.     

Prognostic value of blood lactate, base deficit, and oxygen-derived variables in an LD50 model of penetrating trauma

OBJECTIVE: To determine whether blood lactate, base deficit, or oxygen-derived hemodynamic variables correlate with morbidity and mortality rates in a clinically-relevant LD50 model of penetrating trauma. DESIGN: Prospective, controlled study. SETTING: University research laboratory. SUBJECTS: Anesthetized, mechanically-ventilated mongrel pigs (30+/-2 kg, n = 29). INTERVENTIONS: A captive bolt gun delivered a penetrating injury to the thigh, followed immediately by a 40% to 60% hemorrhage. After 1 hr, shed blood and supplemental crystalloid were administered for resuscitation. MEASUREMENTS AND MAIN RESULTS: After penetrating injury, 50.7+/-0.3% hemorrhage (range 50% to 52.5%), and a 1-hr shock period, seven of 14 animals died, compared with six of six animals after 55% to 60% hemorrhage, and 0 of nine animals after < or =47.5% hemorrhage. Only two of 13 deaths occurred during fluid resuscitation. At the LD50 hemorrhage, peak lactate concentration and base deficit were 11.2+/-0.8 mM and 9.3+/-1.5 mmol/L, respectively, and minimum mixed venous oxygen saturation, systemic oxygen delivery, and systemic oxygen consumption were 33+/-5%, 380+/-83 mL/min/kg, and 177+/-35 mL/min/kg, respectively. For comparison, baseline preinjury values were 1.6+/-0.1 mM, -6.7+/-0.6 mmol/L, 71+/-3%, 2189+/-198 mL/min/kg, and 628+/-102 mL/min/kg, respectively. Of all the variables, only lactate was significantly related to blood loss before and after fluid resuscitation in the 16 survivors. However, r2 values were relatively low (.20 to .50), which indicates that only a small fraction of the hyperiactacidemia was directly related to tissue hypoperfusion. In the whole population of survivors and nonsurvivors, both lactate and base deficit (but none of the oxygen-derived variables) correlated with blood loss. CONCLUSIONS: Arterial lactate is a stronger index of blood loss after penetrating trauma than base deficit or oxygen-derived hemodynamic variables. The reliability of arterial lactate depends on several factors, such as the time after injury, the proportion of survivors and nonsurvivors in the study population, and on factors other than tissue hypoxia.     

Multiple orifice synthetic jet for improvement in impingement heat transfer

Synthetic jet is potentially useful for cooling of electronic components and its utility has been investigated in previous studies. Synthetic jet will become further attractive if additional cooling can be obtained without a corresponding increase in the input power. In this context, we explore the use of multiple orifice single-cavity synthetic jet employed in direct impingement mode of cooling. Experiments are conducted for different configurations with a center orifice surrounded by multiple satellite orifices. The Reynolds number is in the range of 1000–2600 while the normalized axial distance is varied in the range of 1–30 in this study. The maximum heat transfer coefficient with multiple orifice synthetic jet is approximately 12 times that of the natural heat transfer coefficient and up to 30% more as compared to that obtained with a conventional single orifice jet. Interestingly, the average Nusselt number gets maximized at two axial distances-the two peaks can be of comparable magnitude. The appearance, location and magnitude of the two peaks depend on the number of satellite orifices and the pitch circle radius on which the satellite holes lie. It is proposed that a transition in flow behavior from multiple-jet to a combined-jet occurs, which leads to the appearance of this additional peak. The additional peak (at the smaller axial distance) can be utilized in the design of cooling solutions for compact devices. The input power reduces slightly in the multi-orifice case with respect to the conventional design. The average velocity at the surface is also obtained with the help of hot-wire anemometry. The use of multiple orifice synthetic jet does not appear to have been explored earlier and the results are expected to be useful in several practical applications.