Fox nutshell was used as a new precursor for the production of a high surface area activated carbon with zinc chloride activator at 600 °C activation temperature and 2.0 impregnation ratio. The ...Brunauer–Emmett–Teller (BET) surface area of the prepared activated carbon was 2869 m2/g with total pore, micropore and mesopore volume of 1.96, 1.68 and 0.28 cm3/g. Methylene blue and phenol were used as adsorbates for adsorption experiment onto prepared high surface area activated carbon in batch and column scale. Adsorption kinetics of methylene blue and phenol was studied by using commonly kinetic models, i.e., the pseudo-first-order model, the pseudo-second-order model, and the intraparticle diffusion model. The experimental adsorption isotherms of these adsorbates on the prepared activated carbon were analysed using three isotherm models: the Langmuir, Freundlich and Tempkin. The equilibrium adsorption (qe) of methylene blue was increased from 249.88 to 968.74 mg/g and for phenol was increased from 19.84 to 75.37 mg/g when initial concentration was enhanced from 100 mg/L to 500 mg/L. The negative values of the enthalpy change (ΔH0 = −2.93 kJ/mol for MB and −16.92 kJ/mol for phenol) indicate that the MB and phenol adsorption process onto FNAC was exothermic in nature. In column experiments, the effects of the bed height of the packing material and flow rate of methylene blue and phenol onto prepared activated carbon were studied.
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•High surface area activated carbon (FNAC) prepared from Fox nutshell with chemical activation using ZnCl2.•Prepared activated carbon contains high BET surface area of 2869 m2/g and micropore volumes of 1.69 cm3/g.•Prepared activated carbon has been used in the adsorption of methylene blue and phenol from their aqueous solution.•Kinetic and isothermal adsorption studies of both the adsorbates are carried out.•Adsorption capacity of FNAC to methylene blue and phenol at 500 mg/L concentration are 968.74 and 75.37 mg/g, respectively.
Let G be a simple graph on n vertices and \mathcal {I}_G denotes parity binomial edge ideal of G in the polynomial ring S = \mathbb{K}x_1,\ldots , x_n, y_1, \ldots , y_n. We obtain lower bound for ...the regularity of parity binomial edge ideals of graphs. We then classify all graphs whose parity binomial edge ideals have regularity 3. We classify graphs whose parity binomial edge ideals have pure resolution.
The current study investigates the decolorization of Indanthrene Blue RS dye and the optimization of process parameters needed for effective decolorization by the bacterial consortium. The pure ...culture of strain TS8, PMS, and NCH has been isolated from the textile wastewater sample collected from local textile processing units outlet and dye contaminated soil from Odisha, India. A bacterial consortium-BP of Bacillus flexus TS8 (BF), Proteus mirabilis PMS (PM), and Pseudomonas aeruginosa NCH (PA) were developed. The physicochemical parameters were optimized to attain maximum decolorization efficacy. Degradation of Indanthrene Blue RS and the formation of metabolites were confirmed through UV-vis spectroscopy, FT-IR, and GC-MS analysis. The developed consortium-BP showed an enhanced decolorization of Indanthrene Blue RS dye with an Average decolorization rate of 11,088 µg h
within 9 h compared to the individual strains under aerobic conditions. The supplementation of agricultural residual wastes showed increased decolorization efficiency of consortium-BP. Higher reduction in TOC and COD removal (≥ 80%) determined the mineralization of Indanthrene Blue RS by consortium-BP. Significant induction of various oxidoreductive enzymes in consortium-BP compared to that of Individual strains indicates their involvement in the overall decolorization and degradation process, with the higher protein concentration in the intracellular enzymes. Studies on the phytotoxicity effect revealed the non-toxic nature of the degraded products formed on mineralization of Indanthrene Blue RS by consortium-BP. This study represents a new approach for enhanced biodegradation using consortium-BP in treating textile wastewaters containing anthraquinone dyes.
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•Volumetric heat source has been used in modeling of SLM of Ti6Al4V.•Simulation of moving single scan and multi-scan.•Porosity is estimated and compared with the experiment.•Porosity ...forms due to improper melting in the powder bed.•The solidification parameters are calculated to estimate solidified grain structure.
A volumetric heat source is used in numerical modeling of selective laser melting (SLM) of Ti6Al4V powder. Single track and multi-track SLM simulations are performed by varying the two key process parameters-laser power and scan speed. The model is validated with the published experimental results for melt pool shape, size and temperature. The predictions are in good agreement with the experiments at low to medium energy density. The validated model is used for investigating the thermo-fluidic transport during SLM of Ti6Al4V and examining the dependence of the melt pool characteristics on the process parameters. As-solidified porosity is calculated numerically for the multi-track simulations and its formation is delineated with the transport phenomena. The predicted porosity compares reasonably well with the experimental values. Solidification parameters, such as temperature gradients and cooling rate are calculated at the instantaneous location of the solidification front and analyzed. This analysis suggests the formation of fully columnar grains of different sizes along the width and depth of the melt pool. Overall, the model provides a good description of thermo-fluidic transport in SLM of Ti6Al4V powder and the resulting temperature field, melt pool characteristics, as-solidified porosity and the expected grain structure. Based on the current analysis, an optimum processing window of 50–70 J mm−3 energy density is suggested for SLM of Ti6Al4V powder.
•Multiphysics analyses quantify group thermal interaction for geothermal piles.•Proposed power reduction factor quantifies loss in energy harvesting efficiency.•Sustained thermal operation and small ...pile spacing reduce group power output.•Pile diameter and circulation tube orientation do not affect thermal interaction.•Non-uniform placement of geothermal piles causes uneven temperature increments.
This paper employs coupled multiphysics modelling of pile-soil heat exchange to quantify pile thermal interaction and its influence in diminishing the power output expected from a group of geothermal piles. Three-dimensional finite element models, which account for the flow of heat carrier fluid through the circulation tubes and conductive heat transport in pile and soil, are developed for different group arrangements of geothermal piles. Finite element analyses (FEAs) of a pair of geothermal piles reveal the effects of spacing, diameter, orientation of embedded fluid circulation tubes, and thermal operation time of geothermal piles on thermal interaction between the piles. A simple analysis-based expression is proposed to calculate power reduction factor that quantifies thermal interaction between two simultaneously acting geothermal piles. The proposed factor is further employed, in conjunction with the principle of superposition, to estimate power output from a group of geothermal piles. Comparison of predictions using the proposed method with FEA results suggests that the proposed method can successfully predict total energy harvesting efficiency (i.e., power output) of a thermally interacting group of geothermal piles.
A new multi-phase lattice hydrodynamic traffic flow model is proposed by considering the effect of multi-forward looking sites on a unidirectional highway. We examined the qualitative properties of ...proposed model through linear as well as nonlinear stability analysis. It is shown that the multi-anticipation effect can significantly enlarge the stability region on the phase diagram and exhibit three-phase traffic flow. It is also observed that the multi-forward looking sites have prominent influence on traffic flow when driver senses the relative flux of leading vehicles. Theoretical findings are verified using numerical simulation which confirms that the traffic jam is suppressed efficiently by considering the information of leading vehicles in unidirectional multi-phase traffic flow.
•A multi-phase lattice model is presented by incorporating the effect of forward looking sites.•The qualitative properties of proposed model are analyzed theoretically.•Phase diagrams are presented for different parameters.•The effect of forward leading lattices on multi-phase traffic dynamics is examined numerically.
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•Activated carbons were prepared from Fox nutshell by chemical activation using H3PO4.•The prepared activated carbons were characterized by BET Autosorb, FTIR, and FESEM.•The BET and ...microporous surface areas were 2636m2/g and 2042m2/g respectively.•Total pore and micropore volumes were 1.53cm3/g and 1.32cm3/g respectively.
Activated carbons were prepared from Fox nutshell by chemical activation with H3PO4 in N2 atmosphere and their characteristics were studied. The effects of activation temperature and impregnation ratio were examined. N2 adsorption isotherms characterized the surface area, total pore volume, micropore volume and pore size distribution of activated carbons. Activated carbon was produced at 700°C with a 1.5 impregnation ratio and one hour of activation time has found 2636m2/g and 1.53cm3/g of highest BET surface area and total pore volume, respectively. The result of Fourier-infrared spectroscopy analysis of the prepared activated carbon confirmed that the carbon has abundant functional groups on the surface. Field emission scanning electron micrographs of the prepared activated carbon showed that a porous structure formed during activation.
•Blockchain technology (BCT) in Automotive Supply Chain (ASC) is reviewed.•Exemplified the potential ASC activities for BCT adoption.•A blockchain framework is proposed to digitise and decentralize ...ASC activities.•Proposed an BCT implementation framework for ASC in VUCA world.
As world is affected by demand volatility; process uncertainty; supply chain complexity and information ambiguity forming a VUCA world. To manage this scenario, industries are adopting emerging technologies for business excellence and one among them is Blockchain. Blockchain technology (BCT) is a distributed ledger technology (DLT) that stores transactional records in a tamper-proof and immutable way; it is a promising solution for incorporating transparency and traceability in traditional ecosystem. As automotive industries are facing a Volatile environment, Uncertain schedules & information; Complex supply chain networks, and Ambiguous decisions that cripples the automotive supply chain (ASC). Therefore, BCT can be used to address issues related to ASC in VUCA world. Keeping this in mind, study reported a systematic literature review (SLR) of BCT applications in ASC. More than seventy research papers were reviewed based on different BCT characteristics and applications. Through content analysis, study explored how to link supply chain visibility, information transparency with BCT for an efficient ASC in VUCA world. Moreover, a BCT implementation framework is proposed for ASC, to provide a decision-making approach for practitioners in VUCA world.
In this Concept we discuss how the chemistry of coinage metal complexes based on alkynyl ligands has developed over the past decades. The rich coordination of alkynyl, that exhibit both η1 (end‐on) ...and η2 (side on) modes, includes non‐bridged systems, as well as bridging of up to four (or six) metal centres. Resulting metal clusters often exhibit highly regular structures and typical coordination motifs forming fascinating assemblies exploiting this versatile coordination. Metallophilic interactions are often an important driving force for the formation of large clusters. In addition, the use of co‐ligands as well the possibility to encapsulate counter ions greatly increases the chemical and structural diversity. Herein we attempt to summarize and highlight design principles towards multinuclear homo and hetero‐bi‐metallic coinage metal clusters of alkynyl ligands.
Coin toss: Syntheses, structural traits and properties of alkynyl coinage metals clusters are discussed and compared. Concepts and synthetic strategies are highlighted.
We calculate the shear (
η
) and bulk viscosity (
ζ
) of Self Interacting Dark Matter (SIDM) fluid using the kinetic theory formalism. Using the astrophysical constraints on dark matter ...self-interaction cross section over mass
σ
/
m
, we demonstrate that viscous SIDM fluid violates the lower bound on the ratio of shear viscosity to its entropy density,
η
/
s
=
1
4
π
. Then, considering the
η
/
s
bound as universal, we derive a theoretical upper limit on the ratio of velocity average dark matter self interaction cross-section to its mass and also estimate an upper limit on SIDM mass. We report that mass of the SIDM particle should be sub-GeV scale. Furthermore, with the assumption of a power-law form of
η
and
ζ
, we study its evolution in the light of low redshift observations. We show that at the large redshift, the SIDM viscosity is small, but at the small redshift, it becomes sufficiently large and contributes significantly to cosmic dissipation. As a consequence, viscous SIDM can explain the low redshift observations and also consistent with the standard cosmological prediction.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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