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The abundance and replenishable nature of biomass make it a suitable fuel for power generation. Among the various technologies, dual fluidized bed gasification (DFBG) is a suitable technology to generate high-quality syngas from biomass. However, the complexity of hydrodynamics and heat transfer with bed geometry, flow conditions as well as feedstock demands effective research for the design of such system. This study, therefore, focuses on the simulation of hydrodynamics of a dual fluidized bed gasification system. The 2-D two-fluid model (TFM) simulations were performed using Multiphase Flow with Interphase eXchanges (MFiX) software by varying the superficial air velocities for both the gasifier and riser. The influence of superficial air velocity on static pressure, pressure drop, axial and radial voidage, solid velocities, and granular temperature was evaluated. From the simulations, it was observed that with the increase in superficial air velocities, there was an increase in the effective height of pressure drop (66%), voidage, and solid velocities of the gasifier. For the simulation of the riser, similar trends in the profile of hydrodynamic parameters were also observed. The optimum velocity for the gasifier and riser has been suggested to be between 0.15 and 0.35 m/s and 6–7 m/s, respectively. [ABSTRACT FROM AUTHOR]

This study looks at how radiation and heat move through a two-dimensional, unsteady Darcy-Forchheimer MHD flow that flows across a porous, stretched plate that is vertically inclined and has a transverse magnetic field applied to it. We use the MATLAB bvp4c approach to numerically translate the controlling boundary layer nonlinear PDEs, which are partial differential equations, into a set of nonlinear ODEs, which are ordinary differential equations, using the similarity transformation. We quantitatively assess the velocity and temperature profiles using graphs that represent the problem's various characteristics, including unsteadiness, Prandtl number, magnetic, Grashoff number, radiation parameter, and Eckert number. Tables illustrate the effects on skin friction (τ) and Nusselt number (Nu). The velocity profile decreases as the magnetic and inertial parameters increase, and the temperature profile decreases with the increases in the radiation parameters. [ABSTRACT FROM AUTHOR]

An in situ hydrolysis of the P–Cl bonds of the carbophosphazene [{NC(NMe2)}2{NPCl2}] (LPCl2) in the presence of hydrated lanthanide(III) nitrates in a dichloromethane and methanol (2 : 1) solvent mixture afforded a series of novel 1D coordination polymers: [{Ln(LHPO2)3(NO3)2(CH3OH)(H2O)} (Cl)]n {where Ln(III) = Gd (1), Tb (2), Dy (3), or Er (4) and LHPO2 is the hydrolyzed carbophosphazene (LPCl2) ligand}. X-ray crystallographic analysis revealed that complexes 1–4 are isostructural and crystallized in the monoclinic crystal system having P21/c space group. The coordination polymers are formed because of the involvement of the geminal P(O)(OH) moieties of the carbophosphazene ligand. Each lanthanide(III) ion is 9-coordinate (9O) in a distorted muffin geometry. Magnetic measurements revealed that both DyIII and ErIII analogues exhibit field-induced single-molecule magnet (SMM) behavior at 0.8 kOe and 2.2 k Oe, respectively. At such dc fields, the dynamic magnetic susceptibility displays complex behavior with a triple magnetic relaxation contribution for 3, while two contributions were identified for 4. The observed static and dynamic magnetic behavior for complexes 1–4 were further rationalized with the aid of BS-DFT and CASSCF/SO-RASSI/SINGLE_ANISO calculations. [ABSTRACT FROM AUTHOR]

A rigid pentadentate chelating ligand (H2L) has been utilized to synthesize a series of octacoordinate mononuclear complexes, [Dy(L)(Ph3PO)(OOCR)] (where R = C6H5 (1), C(CH3)3 (2), CF3 (3)) and a dinuclear complex, [Dy2(L)2(Ph3PO)2{(OOC)2C6H4}] (4) based on the highly anisotropic Dy(III) ion. All the complexes were structurally characterized by single-crystal X-ray diffraction studies. The complexes were formed by the coordination action of the dianionic pentadentate ligand [L]2−, one phosphine oxide, and carboxylate ligands. DC and AC magnetic measurements were performed on 1–4. Complexes 1–4 show SMM behaviour, under zero DC field for 1 and 4, and under 500 Oe and 1000 Oe DC fields for 2 and 3 respectively, with thermally activated, Raman, and Raman and quantum tunnelling dominant relaxation mechanisms for 1 and 2, 3 and 4, respectively. [ABSTRACT FROM AUTHOR]

Synthesis of core‐modified 28π non‐fused hexaphyrin is reported. The optical and 1H NMR spectral analysis reveals the non‐aromatic nature of the macrocycle in its freebase form at 298 K. However, the non‐aromatic nature of the macrocycle remains unaltered upon lowering the temperature. The structural elucidations for the freebase macrocycle also justify the non‐aromaticity of the freebase 8, where the thiophene units of the 1,2 diphenyl 1,2 dithienyl ethene moiety is deviated maximum from the overall macrocyclic framework. Protonation on the imino pyrrolic nitrogens results in single–crystal X‐ray structures of 8 which show essential distortion in macrocyclic framework needed for the effective π‐electron delocalization, attaining Möbius aromaticity. The Nucleus Independent Chemical Shift (NICS) values for the freebase and protonated macrocycles are −2.0 ppm and −5.6 ppm. The Anisotropy Induced Current density shows the clockwise delocalization of current density vectors. Overall, the spectral, structural and theoretical analysis suggests nonaromatic in freebase and Möbius aromatic nature of the protonated hexaphyrin. [ABSTRACT FROM AUTHOR]

The abundance and replenishment nature of solid biomass prompt fuel substitution for gasification and thermal power plants. However, many challenges are encountered while utilizing raw biomass, such as seasonality, strong hydrophilicity, low bulk and energy density, excess oxygen content, less compositional homogeneity, and poor grindability. It is, therefore, indispensable to augment the thermo-chemical properties of the solid biomass by performing suitable pretreatment. Among the various pretreatment techniques, non-oxidative torrefaction effectively upgrades solid biomass to coal-like fuel altering its physico-chemical properties. Therefore, in this work, torrefaction of rice husk and sugarcane bagasse have been performed in a fixed bed reactor by varying temperatures from 210–330 °C and residence time from 30–60 min under a non-oxidative environment. The experimental investigation illustrates a decrease in mass and energy yield of the biomass with a rise in temperature and residence time. Conversely, the higher heating value of rice husk and sugarcane bagasse has improved by 119.4% and 128.9%, respectively. The hydrogen-to-carbon (H/C) and oxygen-to-carbon (O/C) ratio of the torrefied biomass has reduced to enriched fuel variety as indicated by the van Krevelen plot. The decomposition and structural modifications were assessed using Fourier transform infrared spectroscopy, x-ray diffraction, and morphology analysis. Based on the experimental observations, it has been found that torrefaction of rice husk at 290 °C and 30 min and sugarcane bagasse at 270 °C and 30 min would generate enriched syngas using a dual fluidized bed gasification system. Furthermore, water gas shift reactions will be promoted to enhance the percentage of hydrogen in the gas mixture. [ABSTRACT FROM AUTHOR]

A rotating fluidized bed in a static geometry dryer without a slit is highly recommended in multiple operations, such as separation, mixing, gasification, combustion, particle coating, and drying process intensification. The present analysis proposed a highly efficient moisture removal technique into optimized energy forms, including electrical and thermal energy used in air heating and particle fluidization. Hence, to reduce a considerable energy loss in rotating fluidized bed chambers, the energy exergy analysis of granular drying is carried out for two distinct drying chambers without and with a slit. Granular drying has been conducted in dryers at 55 °C –65 °C, airflow rate of 400–600 m3/h, drying inventory of 300–500 g, energy utilized, and energy utilization ratio. It is observed that. In the slit-less rotating fluidized bed with static geometry dryer, the drying efficiency is increased by 5.6%, the drying cost decreased by 19.8%, and the payback period is reduced by 54% compared to the rotating fluidized bed dryer in static geometry. [ABSTRACT FROM AUTHOR]

The synthesis, structure and magnetic properties of homometallic hexanuclear lanthanide complexes [Ln6(HL)4(tfa)4(S)2]·2NO3·x H2O·yMeOH (1, Ln = Gd, S = MeOH, x = 0, y = 0; 2, Ln = Tb, S = H2O, x = 2, y = 2; 3, Ln = Dy, S = MeOH, x = 0, y = 2; 4, Ln = Er, S = MeOH, x = 0, y = 2). [(H4L) = 6-((bis(2-hydroxyethyl)amino)-N′-(2-hydroxybenzylidene)picolinohydrazide) (tfa = trifloroacetylacetone)] are reported. These hexanuclear assemblies are made up of two trinuclear triangular sub-units linked through the oxygen atoms of two phenoxide bridging groups in a corner sharing arrangement. Magnetic studies reveal that 1 displays a magnetocaloric effect with a maximum value of −ΔSm = 21.03 J kg−1 K−1 at T = 3 K and under an applied field change ΔB = 5 T. Complex 3 shows slow relaxation of magnetization even under zero applied field although a clear maximum in the ac susceptibility plots cannot be seen. However, under an optimal applied field of 0.2 T, clear maxima are observed in the out-of-phase (χ′′M) component of the ac susceptibility in the temperature range 3.5 K (2 kHz) to 10.5 K (10 kHz). The temperature dependence of the relaxation times could be fitted to the sum of Orbach, Raman and QTM relaxation processes affording the following parameters: τo = 3.4(9) × 10−8 s, Ueff = 94(2) K, BRaman = 16.43(1) K−n s−1, n = 3.2(3) and τQTM = 0.0044(3) s. 4, under an applied magnetic field of 0.2 T, shows slow relaxation of magnetization through a thermally activated Orbach process with Ueff = 18.2(9) K and τo = 3.5(3) × 10−8 s. [ABSTRACT FROM AUTHOR]

We report the synthesis of [(L)DyIII(Cy3PO)2]·[BPh4] (1-Dy) (where H2L = 2,6-diacetylpyridine bis-benzoylhydrazone and Cy = cyclohexyl) which crystallized in the triclinic, P1¯ space group. The local geometry around Dy(III) in 1-Dy was found to be pentagonal bipyramidal (pseudo-D5h). The AC magnetic susceptibility measurements performed on 1-Dy and on its diluted 1-Y(Dy) samples showed a typical single-molecule magnet signature revealed by the appearance of AC-frequency dependent out-of-phase susceptibility signals in the absence of a static magnetic field. The out-of-phase AC susceptibility signals were well resolved on the application of a small magnetic field (HDC = 500 Oe) and yielded an energy barrier for magnetization flipping of Ueff/kB = 50 K for the diluted derivative. The magnetic studies on 1-Dy and 1-Y(Dy) and data analysis further confirm that Raman and QTM under-barrier magnetic relaxations play a crucial role in lowering Ueff despite the almost axial nature of the Dy(III) ion in 1-Dy. We have rationalized these observations through detailed ab initio calculations performed on the X-ray crystal structure of 1-Dy. [ABSTRACT FROM AUTHOR]

Regulated oxidative stress (OS) is important during pregnancy. Sporadic studies suggest the significance of deregulated OS in hepatitis E virus (HEV) infected pregnancy, but with limited reactive oxygen species (ROS) or antioxidant markers. The present novel study, therefore, aimed to evaluate the significance of ROS‐antioxidant imbalance and resulting altered OS in HEV infected pregnancy complications like preterm delivery (PTD) and outcome. Difference in serum levels of ROS and antioxidant panel of markers were evaluated by ELISA for HEV immunoglobulin M RNA positive genotype 1 cases (including acute [acute viral hepatitis, AVH] and fulminant [fulminant hepatic failure, FHF] cases) and healthy term delivery subjects, and analyzed statistically. Direct ROS marker H2O2 levels and indirect OS marker for DNA damage 8‐hydroxy‐2′‐deoxyguanosine was significantly increased in HEV‐cases compared to controls, and was associated and prognostic factor for PTD and fetal death in HEV cases. A comparatively lower total serum antioxidant capacity was observed in the FHF cases compared to the control subjects and the AVH cases. Glutathione (GSH) levels and superoxide dismutase (SOD) activity were significantly associated with PTD in the FHF sub‐cohorts (p = 0.017) and AVH sub‐cohorts (p < 0.001), respectively, and was associated with poor prognosis in HEV cases. The serum H2O2 levels were found to be negatively correlated with SOD activity (p = 0.016) and GSH levels (p = 0.001) in the HEV‐AVH cases; and positively correlated with the viral load in HEV cases (p = 0.023). The ROS‐antioxidant imbalance resulting OS plays a detrimental associative role in HEV infected pregnancy complications like PTD and adverse pregnancy outcomes; and holds therapeutic significance. [ABSTRACT FROM AUTHOR]

Parsers are omnipresent in almost all software systems. However, an operational implementation of parsers cannot answer many "how", "why" and "what if" questions, why does this parser not accept this string, or, can we have to parser for it to accept a set of strings? To lift the parsing theory to answer such questions, we build a symbolic encoding of parsing. Our symbolic encoding, that we referred to as a parse condition, is a logical condition that is satisfiable if and only if a given string w can be successfully parsed using a grammar G . We build an SMT encoding of such parse conditions for LL(1) grammars and demonstrate its utility by building three applications over it: automated repair of syntax errors in Tiger programs, automated parser synthesis to automatically synthesize LL(1) parsers from examples, and automatic root cause analysis of parser construction to debug errors in parse tables. We implement our ideas into a tool, Cyclops , that successfully repairs 80% of our benchmarks (675 buggy Tiger programs), clocking an average of 30 s per repair, synthesize parsers for interesting languages from examples, and ranks the ground truth as the topmost ranked reason for failure in more than 85% of our instances. On our deployment of Cyclops in a compiler design course, 91 of 128 students gave a positive response stating that assistance from Cyclops was indeed useful. [ABSTRACT FROM AUTHOR]

The present investigation involves the numerical studies on the thermochemical conversion of bamboo biomasses conducted in a Double Tapered Bubbling Fluidized Bed Reactor. Six different bamboo biomass species suitable for the gasification process available in Mizoram state, India, are selected for the study. The 0D equilibrium-based model predicts the percentage composition of syngas constituents viz; H2, CO, CO2, H2O, and CH4 obtained through the gasification process. The global gasification reaction of biomass is formulated from the chemical reactions at various gasification stages. The composition of constituents in the syngas obtained is numerically determined at varied temperature ranges (400–1400 K) and Moisture content (0–40%). The percentage of syngas constituents obtained for Bambusa vulgaris Wamin is outstanding compared to the other biomass species used in the study. The production of CH4 is found suitable at low temperature (< 1000 K) and moisture content (< 35%). The result presented over the equivalence ratio range of 0.2–0.5, and gasification temperature of 1073 K, better recognizes the percentage yield of the syngas components. However, the percentage of H2 and CO2 increases due to the water gas shift reaction with the temperature rise. The obtained results are suitably compared with the literature in the same areas. [ABSTRACT FROM AUTHOR]

This research manifests the performance analysis of a novel slit-less rotating fluidized bed in static geometry (SL-RFBSG) using a local food grain paddy. From the economic point of view of the drying process, system economy, and system complexity, this dryer is developed without slit and rectangular air inlets. The performance of the developed dryer is evaluated, considering the effect of various operating parameters, namely loading capacity of grain, operating temperature, air flow rate, drying time and grain quality. The SL-RFBSG dryer's energy utilization, product quality, and overall drying performance are affected by increasing drying air temperature, air flow rate, and inventory. Hence, the drying efficiency of the developed dryer is increased by 20.5%, while 78% of milling rice is recovered. [ABSTRACT FROM AUTHOR]

Production of clean energy from biomass through thermochemical conversion techniques has gained substantial momentum over the last decades. The biomass gasification is a noteworthy thermochemical conversion technique due to its varied advantages like feed material flexibility and ease of operation. Here in this work, the effects of applying air preheating for the gasification of biomass (dry wood) under varied particle size (100, 300 and 800 µm) and its outcome are simulated using ANSYS FLUENT 14.0. Two-fluid model is used for the simulation study with distinct phases—air (Phase-1) and wood (Phase-2). The boundary conditions are applied, and the simulation results obtained are matched with available studies. The inlet velocity of the gasifying medium is varied from 0-3m/s analogous to the bubbling fluidized bed velocity range. The gasification temperature ranges are 973, 1073 and 1173 K. The simulations are conducted with and without preheated air in a double-tapered bubbling fluidized bed reactor having taper angle of 5°.The fluid velocity and taper angle play an essential role in controlling the solid particle suspension rate inside the reactor chamber. However, the air preheating maintains the overall reactor temperature that enhances the solid–gas conversion rate. [ABSTRACT FROM AUTHOR]

The application of biochar in agricultural practices and vegetative slopes has been rigorously recommended in previous literature. However, its potential application in other industries is scarcely explored. Biochar is a chemically stable material with a low thermal conductivity, which makes it a perfect fit for blending with soil to use as thermal backfills. A thermal backfill is an essential component for maintaining the ambient temperature around the underground pipelines and storage tanks of crude oil industries. This study investigates the potential application of eighteen soil-biochar blends as thermal backfill. Highly plastic silt and clayey sand (SC) soil were amended with three different biochar types viz. hardwood biochar, water hyacinth biochar, and sugarcane bagasse biochar (SBBC), at three biochar contents of 2.5%, 5%, 7.5% (w/w). Thereafter, their compaction characteristics, thermal and physicochemical properties were investigated. The thermal conductivity (K) and volumetric heat capacity (C) of MH soil were reduced by 22%, 29%, 33%, and 16%, 24%, 26% with 7.5% amendment of hardwood, water hyacinth, and SBBC. Similarly, K and C values of SC soil decreased by 22%, 34%, 37%, and l2%, 18%, and 20%. The micrographic analysis of soil-biochar blend reveals that the entrapped air in biochar particles governs the heat transfer in biochar-amended soil. An inverse correlation of thermal conductivity with pH and electrical conductivity was also observed for the soil-biochar mixes. This study extends the domain of biochar application highlighting the engineering properties of different blends, which would be helpful for its field-scale application. [ABSTRACT FROM AUTHOR]

In the present research, a parametric study of a pilot-scale gas–solid vortex reactor (GSVR) with static geometry dryer has been carried out. It is an intense and clean energy technology of the granular material drying, which is highly applicable in various industrial operations, namely particulate coating, granular drying, mixing, agglomeration, separation, milling, combustion, etc. The foremost feature of this reactor is its compact size through which higher heat and mass transfer take place. Observing intense heat and mass transfer characteristics of the GSVR reactor, a pilot-scale GSVR dryer has been developed that dry the granular material rapidly. The goal of the present study is to examine the performance of the developed reactor, by means of experimental investigations, considering various operating parameters such as air pressure, temperature, suspension density, drying air temperature, airflow rate, and inventory of paddy. The results obtained from the experimental study revealed that the maximum and minimum time of drying is found to be 40 and 20 min for the maximum and minimum loading capacity of 1000 and 400 g, respectively. Hence, overall drying efficiency is improved by increasing the inventory of paddy (800–1000 g). [ABSTRACT FROM AUTHOR]

Summary: Efficiency drop due to increase in photovoltaic (PV) module operating temperature creates a huge difference between the projected and actual electricity generated in large power plants. As a solution to this problem Photovoltaic‐Thermal (PV/T) collector, with PV at top and thermal collector at the bottom has been developed. PV/T can cool the PV as well as generate low‐temperature thermal energy. This article presents a comparative experimental study of two newly developed PV/T collector having transparent solar panel with copper tube absorber arranged in rectangular spiral (PV/T‐RS) and horizontal oscillating (PV/T‐HO) configurations. The PV/T collectors are experimentally evaluated under outdoor conditions at Indian Institute of Technology Guwahati. The developed PV/T's are compared in terms of electrical and thermal efficiencies. The PV/T‐RS is found to be better as compared to PV/T‐HO in terms of electrical output, whereas reverse result is reported in case of thermal output. The average electrical and thermal efficiency was found to be 11.2% ± 0.95% and 57.11% ± 2.94% for PV/T‐RS. The calculated average thermal efficiency of PV/T‐HO (63.6% ± 2.94%) is found to be 11.4% more as compared to PV/T‐RS. The overall exergetic efficiency for PV/T‐RS and PV/T‐HO was found to be in the range 11.8%‐16.2% ± 3.18% and 9.7%‐15.25% ± 3.18%, respectively. [ABSTRACT FROM AUTHOR]

Background Limited supply, cost and potential for severe adverse effects observed with the blood derived rabies immunoglobulin products has led to search for alternative therapies. This issue has been addressed by developing an anti-rabies monoclonal antibody cocktail. Methods This is a phase 3, randomized, open-label, noninferiority trial conducted in patients with World Health Organization (WHO) category III exposure with suspected rabid animal. Eligible patients were assigned to either the test arm, TwinrabTM (docaravimab and miromavimab) or the reference arm, human rabies immunoglobulin (HRIG; Imogam® Rabies-HT), in a ratio of 1:1. The primary endpoint was the comparison of responder rates between the 2 arms assessed as percentage of those with rabies virus neutralizing antibodies titers ≥0.5 IU/mL on day 14. Results A total of 308 patients were equally randomized into the 2 arms. In the per-protocol (PP) population, there were 90.21% responders in the TwinrabTM arm and 94.37% in the HRIG arm. The geometric mean of rapid fluorescent foci inhibition test titers in the PP on day 14 were 4.38 and 4.85 IU/mL, for the TwinrabTM and HRIG arms, respectively. There were no deaths or serious adverse events reported. Conclusions This study confirmed that TwinrabTM is noninferior to HRIG in terms of providing an unbroken window of protection up to day 84. This trial in healthy adults with WHO category III exposure from suspected rabid animal also establishes the safety of TwinrabTM in patients with 1 WHO approved vaccine regimen (Essen). Clinical Trials Registration CTRI/2017/07/009038. [ABSTRACT FROM AUTHOR]

Two neutral, isostructural, octanuclear, LnIII complexes, [Ln8(HL)6(L)2(μ3-OH)4(μ2-OH)2(H2O)4].solv (Ln = Gd(III), (1Gd) and Dy(III), (2Dy) have been synthesized using LnIII nitrate salts and a o-vanillin-supported multi-dentate ligand, N'-(2-hydroxy-3-methoxy-5-nitrobenzylidene)-2-(hydroxyamino) propanehydrazide (H3L) in the presence of tetramethyl ammonium hydroxide. The complexes were structurally characterized by single crystal X-ray diffraction studies. The complexes are held by the cumulative coordination action of six [HL]2−, two [L]3− chelating ligands, H2O and hydroxide ligands. Magneto-structural analysis of complexes 1Gd and 2Dy reveals the presence of intramolecular antiferromagnetic interactions between the LnIII ions. Magneto-caloric effect was analysed for the complex 1Gd which shows a maximum in the change of molar entropy (–ΔSm) of magnitude 25.5 J kg–1 K–1 at T = 3 K and an applied field change ΔB = 5 T. [ABSTRACT FROM AUTHOR]

Summary: This study has dealt with the synthesis and characterization of biochars produced from three biomasses, viz. water hyacinth (whole plant and its components), yellow oleander, and sugarcane bagasse, and their comparative assessment for potential application in agronomy and energy production. The pyrolysis was carried out in a fixed batch reactor at 350°C and 550°C with a heating rate of 20°Cmin−1. Biochars were characterized for proximate and ultimate (elemental) analysis, and also using standard techniques (SEM, EDX, TGA, BET, XRD, and FTIR). Biochars produced at 550°C from all the feedstock had good properties (carbon content: 39.09‐80.74%, pH: 7.36‐10.42, calorific value: 16.98‐30.18 MJ kg−1, and ash content: 0.89%‐21.78%). Moreover, relatively low atomic ratios (H/C 0.25‐0.47 and O/C 0.15‐1.11) of all biochars indicated their potential as solid fuel. XRD results showed the presence of amorphous and crystalline structures, and minerals like sylivite, quartz, kalsilite, and tridymite in the biochar. Biochar produced from sugarcane bagasse at 550°C possessed the best properties: fixed carbon (77.42%), bulk density (0.13 kg/m3), brunauer–emmett–teller (BET) surface area (17.78 m2/g), pore size (12.86 nm), total pore volume (0.025 cm3/g), calorific value (30.18 MJ kg−1), ash content (1.16%), and moisture content (2.03%). [ABSTRACT FROM AUTHOR]

Single-molecule magnets involving monometallic 4f complexes have been investigated extensively in last two decades to understand the factors that govern the slow magnetization relaxation behavior in these complexes and to establish a magneto-structural correlation. The prime goal in this direction is to suppress the temperature independent quantum tunneling of magnetization (QTM) effect via fine-tuning the coordination geometry/microenvironment. Among the various coordination geometries that have been pursued, complexes containing high coordination number around Ln(III) are sparse. Herein, we present a summary of the various synthetic strategies that were used for the assembly of 10- and 12-coordinated Ln(III) complexes. The magnetic properties of such complexes are also described. [ABSTRACT FROM AUTHOR]

Electric vehicles that run on batteries have a major disadvantage of temperature abnormalities when operated at extreme working conditions. Therefore, thermal management of battery pack is essential to ensure its safety and performance. There are three operation strategies of thermal management air-based, liquid-based, and phase change material-based battery thermal management systems (BTMSs). Optimization studies on BTMSs have been focused mainly on the structural parameters as compared to the operating parameters. In liquid cooled multichannel flow-type BTMSs, equal flow rates are employed in all the channels. However, only a few studies have focused on variable coolant flow rates in channel-type liquid BTMS and its optimization. In this paper, a multichannel cold plate-based liquid BTMS is proposed for Lithium-ion battery pack comprising of two prismatic cells operating at 1 C discharge rate. Multi-objective optimization (MOO) technique coupled with computational fluid dynamics (CFD) simulations is used for obtaining optimal mass flow rate combination of coolant in the channels for reducing the power consumption of the BTMS without compromising on its thermal performance. Response surface methodology is adopted for the sensitivity analysis of the operating parameters and Multi Objective Genetic Algorithm (MOGA) approach is used to obtain the optimal solution set. The results showed a maximum reduction of 66.33%, 38.10%, and 43.56% for mass flow rate, maximum pressure and power consumption respectively in comparison to equal mass flow rate case whereas the temperature rise and temperature distribution of the battery system remain within the nominal range. [ABSTRACT FROM AUTHOR]

The reaction of a bulky acetyl acetone ligand 1,3-dimesitylpropane-1,3-dione (MesacacH) with hydrated lanthanide chlorides in the presence of tetramethylammonium hydroxide afforded a new family of neutral mononuclear LnIII complexes [Ln(Mesacac)3(DMF)] (Ln = Dy (1); Tb (2); Y0.91Dy0.09 (3); and Er (4)). The molecular structures of these complexes were confirmed by single crystal X-ray diffraction studies. The coordination geometries of the LnIII centre were analysed by SHAPE analysis which revealed a capped octahedral geometry in 1–4. Photoluminescence studies showed ligand-sensitized green emissions for 2 with an appreciable quantum yield of 0.83%. Static (dc) and dynamic (ac) magnetic studies of complexes 1 and 3 were performed. The dynamic magnetic study revealed that complex 1 exhibits zero-field slow relaxation of the magnetization without showing a clear maximum in the out-of-phase ac susceptibility plots. However, magnetic dilution of 1 with the YIII metal ion (complex 3) and/or the application of a dc magnetic field induces a strong frequency dependence of the ac susceptibility signals with χ′′M peaks in the 3–10 K temperature range, thus supporting field-induced SMM behaviour of 1. The relaxation process takes place through a combination of the Orbach and Raman mechanisms. The fitting of the temperature dependence of the relaxation time to the equation τ−1 = τ0−1 exp(–Ueff/kBT) + BTn, allows the extraction of the effective energy barrier Ueff/kB = 70 K (48.7 cm−1) and pre-exponential parameter of τ0 = 2.7 × 10−7 s for the Orbach mechanism (first term) and the parameters B = 0.04 s−1 K−n and n = 6.11, for the Raman mechanism (second term). [ABSTRACT FROM AUTHOR]

A rotating fluidized bed in static geometry (RFB-SG) without slits is presented in this paper as a research objective. The concept of RFB-SG is highly beneficial in numerous industrial operations such as granular drying, particle coating, mixing, agglomeration, and combustion. In this study, a three-dimensional CFD model is developed using the commercial software ANSYS FLUENT 14.5, to investigate hydrodynamics and heat transfer characteristics of gas–solid in the vortex chamber. The analysis of the flow pattern of gas–solid and the prediction of fluidization capacity have been made, using appropriate parameters. The findings showed that the significant factors, such as inlet air velocity, solid-bed thickness, the volume fraction of solids, solids pressure, and heat transfer coefficient, influenced the reactor capacity. It is observed that the solid inventories of 300 and 500 g have been fluidized perfectly at inlet air velocities of 30 m s−1 and 44 m s−1, respectively. The overall operating and drying costs are found to be decreased due to the reduction in fluidization air requirements. [ABSTRACT FROM AUTHOR]

The major concerns with Lithium‐ion batteries failures are temperature rise and temperature non‐uniformity during adverse operating conditions like fast charging/discharging and extreme ambient conditions (extreme hot/cold weather). These problems lead to safety issues like thermal runaway of the battery pack. To negate these issues and to ensure better performance of the battery pack, battery thermal management system (BTMS) is adopted in EVs. The prominent BTMSs are air‐based BTMS, liquid‐based BTMS and phase change based BTMS. This paper collates various thermal management issues and numerous cooling methods developed to mitigate these problems and throws light on some of the research gaps on recovery and utilization of low‐grade heat generated in the battery pack. [ABSTRACT FROM AUTHOR]

Diradicals have been of tremendous interest for over a century ever since the first reports of p‐ and m‐phenylene‐bridged diphenylmethylradicals in 1904 by Thiele and 1915 by Schlenk. Reported here are the first examples of cyclic(alkyl)(amino)carbene (CAAC) analogues of Thiele's hydrocarbon, a Kekulé diradical, and Schlenk's hydrocarbon, a non‐Kekulé diradical, without using CAAC as a precursor. The CAAC analogue of Thiele's hydrocarbon has a singlet ground state, whereas the CAAC analogue of Schlenk's hydrocarbon contains two unpaired electrons. The latter forms a dimer, by an intermolecular double head‐to‐tail dimerization. This straightforward synthetic methodology is modular and can be extended for the generation of redox‐active organic compounds. [ABSTRACT FROM AUTHOR]

Diradicals have been of tremendous interest for over a century ever since the first reports of p‐ and m‐phenylene‐bridged diphenylmethylradicals in 1904 by Thiele and 1915 by Schlenk. Reported here are the first examples of cyclic(alkyl)(amino)carbene (CAAC) analogues of Thiele's hydrocarbon, a Kekulé diradical, and Schlenk's hydrocarbon, a non‐Kekulé diradical, without using CAAC as a precursor. The CAAC analogue of Thiele's hydrocarbon has a singlet ground state, whereas the CAAC analogue of Schlenk's hydrocarbon contains two unpaired electrons. The latter forms a dimer, by an intermolecular double head‐to‐tail dimerization. This straightforward synthetic methodology is modular and can be extended for the generation of redox‐active organic compounds. [ABSTRACT FROM AUTHOR]

The transient temperature measurements and subsequent prediction of heat flux are prime requirements to quantify instantaneous heat transfer characteristics in short duration unsteady flow phenomena. Coaxial surface junction thermocouples (CSJT) are efficient laboratory tools that can cater both the requirements of measuring continuous as well as instantaneous temperatures. In addition, they have the capability of fast response behaviour for the measurement of transient temperature even in harsh environments. Ease of fabrication process, robustness and cost effectiveness are some of the advantages of CSJTs over its counterparts. The present investigations mainly focus on CSJT as a potential "heat flux sensor" for short duration experiments. For this purpose, an E-type probe (3.25 mm diameter and 10 mm long) was prepared in-house. The fabrication process involves intentional plastic deformation between the two metallic thermo-elements of the probe to achieve a sensing junction of 20 μm. The characterization and quality of the sensing surface is supported through Electron Discharge X-ray (EDX) and Field Emission Scanning Electron Microscope (FESEM) studies. The probe was exposed to a continuous wave laser source of known wattage (in the range of 0.2 W–0.5 W) which acts as a source for step heat load. Transient temperatures recorded from the probe are further processed for heat flux computation through analytical and numerical methods. As a term of inference during the test window of 0.4 s, it is observed that temperature as well as heat flux values have a nice match in trend as well as magnitude with an uncertainty band of ±5%. [ABSTRACT FROM AUTHOR]

Highly symmetric enneanuclear copper(II) phosphates [Cu9(Pz)6(μ-OH)3(μ3-OH)(ArOPO3)4(DMF)3] (PzH = pyrazole, Ar = 2,6-(CHPh2)2-4-R-C6H2; R = Me, 2MeAr; Et, 2EtAr; iPr, 2iPrAr; and Ar = 2,6-iPr2C6H3, 2Dip) comprising nine copper(II) centers and pyrazole, hydroxide and DMF as ancillary ligands were synthesized by a reaction involving the arylphosphate monoester, 1, copper(I)chloride, pyrazole, and triethylamine in a 4 : 9 : 6 : 14 ratio. All four complexes were characterized by single crystal structural analysis. The complexes contain two distinct structural motifs within the multinuclear copper scaffold: a hexanuclear unit and a trinuclear unit. In the latter, the three Cu(II) centres are bridged by a μ3-OH. Each pair of Cu(II) centers in the trinuclear unit are bridged by a pyrazole ligand. The hexanuclear unit is made up of three dinuclear Cu(II) motifs where the two Cu(II) centres are bridged by an –OH and a pyrazole ligand. The three dinuclear units are connected to each other by phosphate ligands. The latter also aid the fusion of the trinuclear and the hexanuclear motifs. Magnetic studies reveal a strong antiferromagnetic exchange between the Cu(II) centres of the dinuclear units in the hexanuclear part and a strong spin frustration in the trinuclear part leading to a degenerate ground state. [ABSTRACT FROM AUTHOR]

We report the influence of N-heterocyclic carbenes (NHCs) on the hydrolysis of a diphosphene TerP＝PTer (1; Ter = 2,6-Mes2C6H3; Mes = 2,4,6-Me3C6H2), a phosphorus-analogue of an alkene. The diphosphene 1 itself is completely inert towards water. However, NHCs have been found to activate 1 towards ready hydrolysis. While sterically less-encumbered NHCs react with 1 affording NHC-adducts which are in equilibrium with 1 in solution, sterically encumbered NHCs do not bind to 1 at all. Interestingly, in both of these situations hydrolysis of the P＝P motif proceeds efficiently. At low temperatures, sterically less-encumbered NHCs are catalytic while the sterically encumbered NHCs play a catalytic role at room temperature. To gain insight on this striking influence of NHCs on the hydrolysis of diphosphene detailed low-temperature 31P-NMR studies along with theoretical calculations have been carried out. In addition, systematic hydrolysis studies of all the NHCs used in this study have also been performed. [ABSTRACT FROM AUTHOR]

Path‐based equivalence checkers (PBECs) have been successfully applied for verification of programmes from diverse domains and from various stages of high‐level synthesis. In the case of non‐equivalence, PBEC provides very little information which is not sufficient for further investigation of the two programmes being compared by some human expert. In this work, the authors show how a counter‐trace (cTrace) can be generated in the case of non‐equivalence reported by the PBEC. Using this cTrace, they also present a procedure to find suitable initialisation values for input variables which reveal the non‐equivalence (i.e. counter‐example) by using off‐the‐shelf satisfiability modulo theories (SMT) solvers. To aid the human expert, they also show that how they can visualise this cTrace in the control and data‐flow graph of the programmes using the graph visualisation software – Graphviz. This counter‐example and visual representation of the corresponding cTrace will be helpful in debugging the root cause of the non‐equivalence. The experimental results are encouraging. [ABSTRACT FROM AUTHOR]

Path-based equivalence checkers (PBECs) have been successfully applied for verification of programmes from diverse domains and from various stages of high-level synthesis. In the case of non-equivalence, PBEC provides very little information which is not sufficient for further investigation of the two programmes being compared by some human expert. In this work, the authors show how a counter-trace (cTrace) can be generated in the case of non-equivalence reported by the PBEC. Using this cTrace, they also present a procedure to find suitable initialisation values for input variables which reveal the non-equivalence (i.e. counter-example) by using off-the-shelf satisfiability modulo theories (SMT) solvers. To aid the human expert, they also show that how they can visualise this cTrace in the control and data-flow graph of the programmes using the graph visualisation software - Graphviz. This counter-example and visual representation of the corresponding cTrace will be helpful in debugging the root cause of the non-equivalence. The experimental results are encouraging. [ABSTRACT FROM AUTHOR]

Herein, we report the synthesis and molecular structures of various magnesium(ii)-phosphate monoesters. By using a bulky aryl substituted phosphate monoester, ArOPO3H2 (Ar = 2,6-(CHPh2)2-4-tBu-C6H2), we have reproducibly assembled mono-, di-, tetra- (cage and ring), hexa-, and polynuclear magnesium(ii)-phosphate monoesters. Interestingly, the hexanuclear magnesium(ii)-phosphate monoester encapsulates an open-cage dodecanuclear water cluster. [ABSTRACT FROM AUTHOR]

The reaction of LnCl3·6H2O with a multidentate flexible Schiff base ligand (LH4), H2O3PtBu and trifluoroacetic acid (tfaH) afforded a series of homometallic tetranuclear complexes, [Ln4(LH2)2(O3PtBu)2(μ2-η1η1tfa)2][2Cl] (Ln = DyIII (1), TbIII (2) and GdIII (3)). The tetranuclear lanthanide core contains two structurally different lanthanide centres, one being in a distorted trigonal dodecahedron geometry and the other in a distorted trigonal prism. Complexes 1–3 were investigated via direct and alternating current (DC and AC) magnetic susceptibility measurements. Only 1 revealed a weak single-molecule magnet (SMM) behaviour. Alternating current (ac) magnetic susceptibility measurements on 1 reveal a frequency-dependent out-of-phase signal. However, the absence of distinct maxima in the χ′′ peak (within the temperature/frequency range of our experiments) prevented deduction of the experimental energy barrier for magnetization reversal (Ueff) and the relaxation time. We have carried out extensive ab initio (CASSCF + RASSI-SO + SINGLE_ANISO + POLY_ANISO) calculations on complexes 1–2 to gain deeper insights into the nature of magnetic anisotropy. Our calculations yielded only one exchange coupling parameter between the two LnIII centres bridged by the ligand (neglecting the exchange between the LnIII centres that are not proximal wrt each other). All the extracted J values indicate a weakly antiferromagnetic coupling between the metal centres (J = −0.025 cm−1 for 1 and J = −0.015 cm−1 for 2). Calculated exchange coupled Ucal values of ∼5 and ∼1 cm−1 in 1 and 2 respectively nicely corroborated the experimental observations regarding weak and no SMM characteristics. Our calculations indicated the presence of a net single-molecule toroidal (SMT) behaviour in complex 2. On the other hand, fitting the magnetic data (susceptibility and magnetization) in the isotropic cluster 3 revealed weak AFM exchange couplings of J1 = 0.025 cm−1 and J2 = −0.020 cm−1 which are consistent with those for GdIII ions. [ABSTRACT FROM AUTHOR]

The reaction of a tridentate NNO donor ligand, 4-nitro-2-((2-(pyridine-2-yl)hydrazono)methyl)phenol (HL) with lanthanide(iii) nitrates in the presence of triethylamine afforded a new family of neutral mononuclear LnIII complexes [Ln(NO3)(L)2(HOCH3)] (Ln = Gd; (1) Tb; (2), Dy; (3), and Ho (4). The mononuclear complexes were structurally characterized by single crystal X-ray diffraction studies which revealed a spherical tricapped trigonal prism geometry with a pseudo D3h symmetry around the LnIII centre. Static (dc) and dynamic (ac) magnetic studies have been performed on these complexes. Field-induced single-ion magnet behaviour was observed in the DyIII analogue with an effective energy barrier and an pre-exponential factor of Δ/kB = 68(2) K and τ0 = 1.8 × 10−7 s, respectively. [ABSTRACT FROM AUTHOR]

A family of four dinuclear complexes, [NHEt3]2[Ln2(µ‐NO3)2(NO3)2(HL)2] [Ln = GdIII (1), TbIII (2), HoIII (3), DyIII (4)], were synthesized by the reaction of an enolizable multidentate Schiff base ligand H3L (H3L = N′‐(2‐hydroxy‐3‐methoxy‐5‐nitrobenzylidene)‐2‐(hydroxyimino)propanehydrazide) with hydrated lanthanide nitrates in the presence of NEt3. The molecular structure of complexes 1–4 was confirmed by single‐crystal XRD analysis. All of the centrosymmetric complexes are dianionic, isostructural and each of the LnIII centers is nine‐coordinate and adopts a muffin like coordination geometry as indicated by SHAPE analysis. The dynamic magnetization studies revealed that the compounds 2 and 4 are field‐induced single‐molecule magnets with effective energy barriers,Ueff = 34(2) K (for 2) and 80(3) K (for 4) and pre‐exponential factors, τo = 1.1 × 10–8 s (for 2) and 1.15 × 10–7 s (for 4). The reaction of an enolizable multidentate ligand (H3L) with hydrated lanthanide nitrates in the presence of NEt3 affords isolation of homo dinuclear Ln2 (Ln = Gd, Tb, Ho, and Dy) complexes. Magnetization dynamics reveals that the Tb2 and Dy2 derivatives are field induced single‐molecule magnets with effective energy barriers, Ueff = 34(2) K, and 80(3) K respectively. [ABSTRACT FROM AUTHOR]

Herein we report two different reactivity modes of lithium(aryl)(boryl)amide, 4, when it is reacted with chlorosilanes such as SiCl4 and MeSiHCl2, and chlorophosphine, Ph2PCl. Thus, the reaction of lithium(aryl)(boryl)amide, 4, with MeSiHCl2 leads exclusively to an N-substitution product, 6. On the other hand, the reaction of 4 with SiCl4 and Ph2PCl proceeds completely differently affording exclusively p-aryl-C-substitution products, 5 and 7, respectively. [ABSTRACT FROM AUTHOR]

The study of water clusters in a confined state has received considerable attention. The simplest among such assemblies of water molecules is the water dimer. Stabilizing this unit at ambient conditions in an appropriate host-template, however, has remained a challenge. Herein, we report 2,6-(diphenylmethyl)-4-iso-propyl-phenyl substituted phosphate diesters (both in their neutral and anionic forms) as molecular templates for hosting the water dimer. The robustness of the water dimer within the neutral phosphate-diester ensemble is remarkable. Even when treated with triethylamine the water dimer is not disrupted, while exclusively the P(O)(OH) unit is deprotonated. [ABSTRACT FROM AUTHOR]

Abstract: The addition reactions of N‐heterocyclic carbenes (NHCs) are mostly known to occur through the carbenic centre (C2), which leads to a “normal” adduct. Herein, we report the “abnormal” addition of NHCDip 1 (1,3‐(2,6‐iPr2C6H3)‐imidazole‐2‐ylidene) to a conjugate acid of cyclic (alkyl)(amino)carbene 2 (CAACiPr=1‐iPr‐3,3,5,5‐Me4‐pyrrolinium triflate). Mechanistic study revealed that this reaction proceeded through the in situ formation of 1,3‐(2,6‐iPr2C6H3)‐imidazolium cation 4 and N‐iPr‐substituted CAAC 5 followed by the oxidative addition of compound 5 across the C4−H bond (alias backbone C−H) of compound 4. The in situ formation of compound 5 was also proven by the oxidative addition of it to the N−H group of iPrNH2. DFT calculations also supported the mechanistic findings. A different methodology for the in situ generation of compound 5 by using TMPLi is also described. [ABSTRACT FROM AUTHOR]

Summary: Cleaner energy production system such as direct alcohol fuel cells (DAFCs) are considered as an alternative source for generating cleaner energy. Studies based on design of catalysts, electrodes design, proton exchange membrane, and flow field were conducted for improving its performance characteristic such as power density. However, the less focus was paid on determining the operating conditions considering the uncertainties that will result in an increase of power density of DAFCs. Therefore, the present work proposes a novel comprehensive procedure involving experimental study and evolutionary approach of genetic programming (GP) in formulation of robust power density models for DAFCs. Two uncertainties such as the selection of objective function and variations in measurement of operating conditions are incorporated in framework of GP. The power density models incorporate the formulation of new objective function in GP that will result in higher accuracy of the models. Experiments performed on DAFCs validate performance of the models. Simulation profiler is then generated for models to verify its robustness in uncertain operating conditions. The inferences on relationships between power density and operating conditions for DAFCs are made by surface analysis of the models. [ABSTRACT FROM AUTHOR]

Molecular nano magnets such as single-molecule magnets (SMMs) are a class of coordination complexes with numerous potential applications such as information storage devices, Q-bits in quantum computing and spintronics materials. One of the greatest challenges in taking these molecules to end-user applications lies in devising strategies to control and predict their magnetic properties. In this regard, lanthanide-based compounds are very attractive as they possess appealing magnetic properties such as very high barriers for magnetization reversal, very large blocking temperatures etc. Controlling the microscopic energy levels of lanthanide-based single-ion magnets (SIMs) is a challenging task and to obtain molecules having very large blocking temperatures, it is desirable to enhance the ground state-excited state gap between the mJ levels and also to quench the quantum tunnelling of magnetization that often circumvents the barrier height. One of the strategies that has been developed by us and others in this area is to employ a diamagnetic transition metal ion to achieve this goal. Over the years several diamagnetic ions such as ZnII, NiII (square planar), AlIII and CoIII have been successfully employed to obtain lanthanide-based SMMs with interesting properties. In this perspective, we discuss how incorporation of diamagnetic ion(s) in the cluster aggregation enhances the barrier height for magnetization reversal and hence improves the magnetic properties. We also discuss theoretical studies on such systems based on ab initio calculations performed using CASSCF level of theory. Such studies are helpful in affording an understanding of the role and limitation of the diamagnetic ions in enhancing the barrier height for magnetization reversal of molecular nanomagnets. [ABSTRACT FROM AUTHOR]