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A comparative adsorption study was carried out for methylene blue (MB) and its 3,7-bis(N,N-(2-hydroxyethyl)amino)-phenothiazinium dye analog (MBI). Batch experiments employed aqueous solutions and commercial filter paper. Out of seven kinetic models tested by means of four quality statistical indicators, the pseudo-second-order, the double-exponential, and the bi-linear Weber-Morris equations were best fits. For both dyes, the process was described as a succession of two diffusion-controlled steps. The Freundlich isotherm was chosen from 11 models describing a variety of mechanism assumptions. Physisorption was considered responsible for the dye removal from liquid. Adsorption of MB is thermodynamically favored, whereas that of MBI is sterically hindered. Both processes are exothermic and exhibit reduced randomness at the S-L interface. The paper was found suitable for retaining MB but served rather filtration/purification purposes for MBI.

A novel paper-based dot immune-graphene-gold filtration assay (DIGGFA) for the detection of breast cancer cells was developed based on the photo-thermal effect of graphene oxide (GO)-Au nanocomposite. Anti-EpCAM antibody which specific to the MCF-7 cell surface antigen, was immobilized on the nitrocellulose paper. The GO-Au-anti-EpCAM composite would interact with the MCF-7 cells captured on the nitrocellulose paper. After the test zone was irradiated by a laser, GO-Au nanocomposite could generate heat, temperature contrast was recorded and positive correlated with the cell number. Standard curve was prepared according to the temperature contrast and the cell number. Under optimal conditions, this method could detect a minimum of 600 MCF-7 cells with a near infrared laser and an infrared temperature gun within 15 min. This simple and rapid method could be applied to the clinical diagnosis in hospitals., (Copyright © 2015 Elsevier B.V. All rights reserved.)

The double-wall paper cup is an everyday object that can be used in the laboratory to study heat transfer. The experiment described here has been done by physics students aged 12-13 years; it can also be used in a different context to prompt debate about environmental issues.

In this project, we explore the use of threshold concept theory as a design basis for development of Interactive Virtual Laboratories in thermodynamics. Thermodynamics is a difficult subject for chemical and biological engineering students to master. One reason for the difficulty is the diverse and challenging set of threshold concepts that they must coherently synthesize and be able to apply in a diverse range of contexts. Based on our experience and from reports in the literature, we have identified a set of threshold concepts we propose are critical for mastery of thermodynamics. To help students better learn these concepts, we have been developing Interactive Virtual Laboratories. This paper describes the development and initial investigation of two such laboratories. They are available for instructors to use through the AIChE Concept Warehouse website (http://cw.edudiv.org/). The Interactive Virtual Laboratories are a series of two-dimensional simulations designed to address the targeted threshold concepts. The design of these laboratories is based on allowing students to see and explore alternative representations of the phenomena that they are learning. They allow inquirybased, scaffolded activity, and each has several activities that provide multiple representations. These activities guide students to perform virtual experiments, and also to place the virtual experiments in the context of the concepts that they are learning. They explain concepts in a way that is less abstract and more intuitive to students by providing a dynamic representation of phenomena at a molecular level. Students are expected to answer numerical questions and, whenever possible, predict and explain the effects of macroscopic changes (i.e., pressure, temperature, composition, energy) based on observations of molecular properties. In the study reported in this paper, we investigate how students experience the laboratories and whether the students perceive the simulations are beneficial towards learning. The two interactive virtual laboratories studied address the concepts of Pv work and reversible processes. Eight participants took part in the clinical study outside of the engineering classroom. All students had previously taken a thermodynamics course and had access to a thermodynamics textbook and the internet as they completed the laboratory. A "think aloud" protocol was used where students were audio recorded as they verbally described their actions in completing the laboratory. The transcribed audio recordings together with video recordings of the computer screen on which they worked were analyzed. After completing the laboratory, a semi-structured interview asked participants about their perceptions of the simulation's effectiveness, their previous thermodynamics experience, and a brief assessment of what they learned. All interviews were transcribed for analysis. The participants generally responded positively to the simulations. Seven out of eight students explicitly stated that the dynamic simulations helped them visualize and engage with the processes more than they could with the static depictions in books or lecture. However, some difficulties were observed, including interacting with the interface and understanding specifically what a question was asking. One participant found the interactivity to be unintuitive. We also noticed a relation between how the participants framed knowledge and their approach to completing the laboratory. Students who activated more sophisticated frames typically completed the simulation more quickly and accurately than those with more naive frames. Students who did not do as well tended to focus on trying to identify equations they had used in the past, even going so far as to use them in an unsuitable context. On the other hand, students who completed the simulations accurately and more quickly appeared to integrate what they were seeing on the screen with their foundational conceptual knowledge to form new understanding.

In this Special Issue of Thermo, a collection of 11 papers is presented based on a preselection of the Editor in Chief of the journal for this particular and specific Special Issue called Feature Papers of Thermo in 2022 [...]

This Special Issue is a collection of papers from some of the leading researchers discussing new findings or cutting-edge developments relating to all aspects of fluid mechanics [...]

In this study, we employ spectroscopic, thermodynamic and molecular docking approaches to identify the mechanism by which thiazolidinone derivatives 4a-4d bind with human serum albumin. It has been suggested that the affinity of the interaction of derivatives 4a-4d with HSA is within the optimal range necessary for the transportation and distribution of compounds within the organism. The binding constant values for the derivative/HSA complexes were found to be 0.03-5.87 × 10 5  M -1 . Both ΔH 0 and ΔS 0 values were negative, which indicates that binding occurs mainly through van der Waals forces and hydrogen bonding. The negative values calculated for ΔG 0 indicate that the binding of derivatives 4a-4d with HSA is a spontaneous process. Our study also reveals that derivatives 4a-4d bind to the subdomain IB (Site III) of HSA and that this binding alters the conformation and thermodynamic stability of HSA. Molecular docking simulations suggest that the main binding forces are van der Waals interactions, hydrophobic interactions and hydrogen bonds. The studied compounds showed weak DPPH-scavenging activity at all of the tested concentrations. The results suggest that compound 4b with a phenyl substituent at the nitrogen atom of the 1,3-thiazolidin-4-one moiety can be considered the most potent antioxidant in the series., (© 2024 John Wiley & Sons, Ltd.)

This study investigates the process conditions of the adsorption of copper (II) ion onto paper mill sludge (PMS) in a batch process. These conditions are: concentration of initial solution, contact time, temperature and quantity of the adsorbent. Characteristic properties of PMS employed as an adsorbent in the experiments were defined using Fourier transform infrared spectroscopy (FT-IR) scanning electron microscopy (SEM) and elemental analyses. According to the obtained results, while the amount of removed copper (II) ion increased with an increase in the rate of the adsorbent and contact time, it decreased as a result of an increase in the temperature and initial solution concentration. Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherms were implemented for the determination of the most appropriate isotherm model for the experimental data, and it was found that the process is in concordance with Langmuir equation. The maximum adsorption capacity of PMS was calculated as 114.42 mg g-1. In kinetic studies, the adsorption process of copper (II) ion onto PMS was controlled by the pseudo-second-order kinetic model. The calculated activation value (Ea) was 38.61 kJ mol-1 and demonstrates that the process occurred by physical adsorption mechanism. The values of the thermodynamic parameters such as enthalpy (ΔHO)(-21.19kJmol-1), free energy (ΔGO) (−8.883 kJ mol-1) and entropy (ΔSO) (0.101 kJ mol-1 K-1) changes were determined to estimate the nature of the process. The results clearly showed that the process was of exothermic and spontaneous nature and that PMS could be utilized as an adsorbent for the removal of copper (II) ion from wastewater. [ABSTRACT FROM AUTHOR]

Rhodanese, the primary cyanide-detoxifying enzyme, plays a crucial role in mitigating the harmful effects of cyanide present in various industrial waste materials, such as battery manufacturing effluents. The bioremediation of cyanide-contaminated environments relies on efficient detoxification mechanisms, making rhodanese a valuable enzyme for biotechnological applications. This research aimed to investigate the biochemical properties of purified rhodanese produced by Aspergillus welwitschiae LOT1, a fungal strain with promising cyanide detoxification capabilities. The purified rhodanese was obtained through fermentation, precipitation, and chromatographic separations, resulting in a homogeneous band of approximately 58 kDa with a specific activity of 374 RU/mg, 28-fold purification, and 14% recovery. The enzyme exhibited optimal cyanide detoxification at pH 7 and 60 °C, with stability observed between 30 and 50 °C and pH 8-10. All metal ions examined except for Cu 2+ enhanced the cyanide-degrading ability of rhodanese. Notably, the enzyme demonstrated a high substrate preference for Na 2 S 2 O 3 and followed a first-order kinetic model and free energy, ΔG of 61.3 kJ/mol, making it a promising candidate for biotechnological applications. Overall, this study provides valuable insights into the biochemical properties of rhodanese from A. welwitschiae LOT1, highlighting its potential for efficient cyanide detoxification and bioremediation., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

This Special Issue is a collection of top-quality papers from some of the Editorial Board Members of Fluids, Guest Editors, and leading researchers discussing new knowledge or new cutting-edge developments on all aspects of fluid mechanics [...]

The Hofmeister series is a series of ions ordered according to their ability to precipitate proteins. It has also been linked to a host of (bio)chemical phenomena. Several attempts over the years to correlate the series to the varying success of different salts in crystallising proteins have been largely inconclusive. A correlation, based on published data and crystallisation conditions for several proteins, is proposed here between some thermodynamic properties of proteins and the position in the Hofmeister series of the salts from which they preferentially crystallise. Namely, a high ratio between the entropic or enthalpic protein-solvent interactions contribution to thermodynamic stability and the total thermodynamic stability of a given protein, indicate the protein's high propensity to crystallise in solutions of highly kosmotropic salts. Low such ratios on the other hand, indicate that chaotropic salts can be equally successful, i. e. that the protein in question is rather indifferent to the Hofmeister character of the salt. Testing various model proteins for crystallisation against screens containing salts found at different points on the Hofmeister series, as well as further bibliographic analysis, have yielded results that appear to largely corroborate this hypothesis. These conclusions may conceivably be used as a crystallisation predictive tool., (© 2024 The Authors. ChemPlusChem published by Wiley-VCH GmbH.)

Hybrid material of surgical mask activated carbon (SMAC) and Fe 2 O 3 (SMAC-Fe 2 O 3 ) composite was prepared by simple co-precipitation method and used as potential material for the remediation of 2,4-dicholrophenol (2,4-DCP). The XRD patterns exhibited the presence of SMAC and Fe 2 O 3 , FTIR spectrum showed the FeO-carbon stretching at the wavenumber from 400 to 550 cm -1 . UV-Vis DRS results showed the band gap was 1.97 eV and 2.05 eV for SMAC-Fe 2 O 3 and Fe 2 O 3 , respectively. The SEM images revealed that the Fe 2 O 3 doped onto the fiber morphology of SMAC. The outcomes of the BET examination exhibited a surface area of 195 m 2 /g and a pore volume of 0.2062 cm 3 /g for the SMAC/Fe 2 O 3 composite. The batch mode study shows the maximum adsorption and photocatalytic degradation efficacies which were 97% and 78%, respectively. The experimental data was studied with both linear and nonlinear adsorption isotherm and kinetics models. The nonlinear Langmuir isotherm and pseudo-second-order kinetics (PSOK) models have well fit compared with other models. The Langmuir maximum adsorption capacity (q max ) was found 161.60 mg/g. Thermodynamic analysis shows that the 2,4-DCP adsorption onto SMAC-Fe 2 O 3 was a spontaneous and exothermic process. The PSOK assumes that the adsorption process was chemisorption. The photocatalytic degradation rate constant of 2,4-DCP was calculated using pseudo-first-order kinetics (PFOK) and the rate constant for SMAC-Fe 2 O 3 and Fe 2 O 3 were 0.859 × 10 -2  min -1 and 0.616 × 10 -2  min -1 , correspondingly. In addition, the obtained composite exhibited good reusability after a few cycles. These results confirmed that SMAC-Fe 2 O 3 composite is an effective adsorbent and photocatalyst for removing 2,4-DCP pollutants., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Points out a different and much simpler approach for the study of equilibria of multiple and heterogeneous chemical reactions. A simulation on coal methanation is used to teach the technique. An example and the methodology used are provided. (MVL)

The chemical system of rubbery elasticity is presented. Several references are given from which to extract experiments and problems for students. (SA)

The converter transformer epoxy impregnated paper bushing is a multi-media electrical equipment, and the main materials include the internal conductor, the external conductor, transformer oil, SF6 gas, the air inside internal conductor, the main insulation material epoxy impregnated paper, sheath, and fittings. In actual operating, the converter transformer bushing is undertaken by the harmonic current with large number of high harmonics and the temperature distribution of the epoxy impregnated paper converter transformer bushings under actual current waveform needs to be researched. What's more, the temperature distribution of the epoxy impregnated paper converter transformer bushings is affected by several factors and to provide basis for the optimization of bushings it's necessary to research about the impact of these factors on the temperature distribution of the epoxy impregnated paper converter transformer bushings. In this paper, on the basis of our previous paper [8], the 3-D temperature distribution of the 400 kV epoxy impregnated paper converter transformer bushing under actual current waveform with large number of harmonics has been simulated by using the computational fluid dynamics (CFD) and finite element method (FEM) analysis. The temperature distribution regularity of the 400 kV converter transformer bushing under different influencing factors has been computed and analyzed. The dissipation structure of the bushing has been optimized and the DC steady-state electric field distribution of the 400 kV converter transformer bushing has been obtained considering the temperature gradient in epoxy impregnated paper. [ABSTRACT FROM PUBLISHER]

Heat pumps have the potential for several applications across various industrial sectors, showcasing significant promise, especially in sectors such as pulp and paper, food and beverage, chemical, non-metallic minerals, and machinery. Envisioning the near future, there is confidence that heat pumps can achieve temperatures above 200 °C, offering substantial potential for utilization in these sectors. Nevertheless, a crucial aspect for the advancement of high-temperature heat pumps is the selection of the fluid. Fluid selection involves considerations of both thermodynamic efficiency and environmental impact, requiring fluids with zero ODP, negligible GWP, and no PFAS. Moreover, it is essential to consider the risks to human health associated with a specific fluid. Despite extensive research, particularly in the realm of vapour compression heat pumps, choosing the most suitable working fluid for these applications is a complex undertaking. Therefore, this paper conducts a theoretical analysis to evaluate potential fluids with suitable thermodynamic properties for high-temperature heat pumps (HTHPs). The comparative results gleaned from this study provide valuable insights for the comprehensive analysis of fluids, showing promise within temperature ranges dictated by specific applications. The metrics employed in the comparison emphasise the merits of fluids in terms of the overall performance, dimensions, and operating ranges of applicable compressor, heat exchange capacity, transport properties, and safety. One noteworthy finding from the analysis is that maintaining a constant HTHP lift (at 40 K) results in having the highest COP across all fluids when the condensing temperature ranges between 85% and 90% of their respective critical temperatures. According to the results of the analysis, natural fluids, including water and alcohols like ethanol or methanol, emerge as particularly compelling candidates. [ABSTRACT FROM AUTHOR]

Abstract: In this study, a pulp and paper mill (PPM) in the SEKA Papermaking Plant in İzmit, Turkey, is analysed through energy and exergy balances. The plant utilises recycled waste paper for papermaking. This type of raw material input makes the process highly sophisticated. The pulping uses strictly mechanical processes, such as digestion, separation by screening and hydrocyclone, and refining. The milling, as an integrated process, provides the final operations necessary to prepare the conditions required for the end-product by stock-preparation, wiring, rolling, and drying by dewatering, pressing, and evaporation. The possibility of making the entire process more thermodynamically efficient is discussed by calculating the energy and exergy losses for all the mechanical and physical sub-processes. The study shows that the energy efficiencies for each of the mechanical and physical steps in the PPM vary between 34% and 97.4%, whereas the exergy efficiencies vary between 30.2% and 94.2%. In conclusion, based on the results from the energy and exergy flow analyses, the exergy output can be improved through more efforts directed primarily to further measurements toward more efficient energy utilisation in the PPM. [Copyright &y& Elsevier]

Tolterodine tartrate (TOTA) is associated with adverse effect, high hepatic access, varied bioavailability, slight aqueous solubility, and short half-life after oral delivery. Hansen solubility parameters (HSP, HSPiP program), experimental solubility (T = 298.2 to 318.2 K and p = 0.1 MPa), computational (van't Hoff and Apelblat models), and thermodynamic models were used to the select solvent(s). HSPiP predicted PEG400 as the most suitable co-solvent based on HSP values (δ d  = 17.88, δ p  = 4.0, and δ h  = 8.8 of PEG400) and comparable to the drug (δ d  = 17.6, δ p  = 2.4, and δ h  = 4.6 of TOTA). The experimental mole fraction solubility of TOTA was maximum (x e  = 0.0852) in PEG400 confirming the best fit of the prediction. The observed highest solubility was attributed to the δ p and δ h interacting forces. The activity coefficient (ϒi) was found to be increased with temperature. The higher values of r 2 (linear regression coefficient) and low RMSD (root mean square deviation) indicated a good correlation between the generated "xe" data for crystalline TOTA and the explored models (modified Apelblat and van't Hoff models). TOTA solubility in "PEG400 + water mixture" was endothermic and entropy-driven. IR (immediate release product) formulation can be tailored using 60% PEG400 in buffer solution for 2 mg of TOTA in 0.25 mL (dosing volume). The isotonic binary solution was associated with a pH of 7.2 suitable for sub-Q delivery. The approach would be a promising alternative with ease of delivery to children and aged patients., (© 2024. The Author(s), under exclusive licence to American Association of Pharmaceutical Scientists.)

The discharge of colored effluent into water bodies is a big concern; hence, the current work was designed to fabricate a superior nanocomposite (NBM) using the Newbouldia laevis husk (NB) and functionalized multiwalled carbon nanotubes ( f- MWCNTs) for the adsorption of malachite green oxalate (MGO). Brunauer-Emmett-Teller (BET) surface analysis was used to assess the specific surface area of NB (0.7699 m 2  g -1 ) and NBM (94.006 m 2  g -1 ). Fourier transform infrared spectroscopy (FTIR) was employed to determine the chemical moieties on the surface of the adsorbent. Field emission scanning electron microscopy (FESEM) and thermogravimetric analysis (TGA) were used to analyze the surface morphology and the thermal behavior of the adsorbents. Essential factors of the adsorption process were investigated, and it was revealed that pH 6.0, adsorbent dose of 0.05 g, contact time 80 min, concentration of 100 mg dm -3 and maximum adsorption capacity of 35.78 mg g -1 (NB) and 69.97 mg g -1 (NBM) were the optimal parameters. The NB and NBM adsorption processes followed a pseudo-first-order kinetic model. The exothermic and endothermic adsorptive processes were noticed to be the best descriptions of MGO elimination by NB and NBM, respectively. The uptake of MGO by NB and NBM was best described by models of Freundlich and Langmuir isotherms. Besides, NBM demonstrated uptake efficiency that is >80% after the fourth adsorption/desorption cycle. As a result, NBM has a wide range of possible uses in environmental remediation.

Exercising in a tropical climate with constant high temperatures and high humidity increases the risk of heatstroke for active people who frequently train outdoors. For these active persons, a cooling source of water nearby can be essential, and this is usually carried in canteen bottles. However, commercially available water canteen bottles have limited thermal insulation capability to keep the liquid content cooled for the required period. This work proposed an engineering solution to enhance the heat insulation performance of water canteen bottles, using recycled cellulose aerogels made from paper waste for the first time as an insulating layer. Recycled cellulose aerogels wrapped around the water canteen bottle provides excellent thermal insulation performance, while not adding significant weight to the bottle. The temperature of the ice slurry in the canteen bottle was measured periodically over four hours with a mercury thermometer. The effects of the static and dynamic conditions on the temperature rate were also quantified. A 1.5 cm thickness of 1.0 wt.% recycled cellulose aerogel wrapped around the canteen bottle can provide an excellent thermal insulation performance with the lowest rise in temperature, achieving a low final temperature of the ice slurry content of 3.5 °C after 4 h. This result is much better than that provided by available commercial bottles under the same conditions.

Spontaneous radial imbibition into thin circular samples of porous material when they have been subjected to radial temperature differences was analyzed theoretically and experimentally. The use of the Darcy equation allowed us to take into account temperature variations in the dynamic viscosity and surface tension in order to find the one-dimensional equation for the imbibition fronts. Experiments using blotting paper showed a good fit between the experimental data and theoretical profiles through the estimation of a single parameter.