Reduction In Enthalpy Research Articles

Microstructure, composition and magnetic properties of Nd-(Fe1-xCox)-B oxide magnetic particles synthesized by Pechini-type chemical method

This work deals with the investigation and optimization of the crystalline phases, magnetic properties, chemical composition and morphology of Nd-(Fe1-xCox)-B oxide magnetic particles (where x = 0, 0.05, 0.1, 0.15, 0.2, 0.3, 0.4, and 0.5) synthesized by Pechini method that can be used as a precursor for the production of Nd2(Fe,Co)14B hard magnetic phase. The polymerization mechanism of Pechini process was investigated by Fourier transform infrared (FTIR) and Raman spectroscopy to confirm the formation of metal-CA complexes and successive esterification reactions between citric acid (CA) and ethylene glycol (EG). The chemical composition of the synthesized samples was studied via energy dispersive (EDS) and X-ray photoelectro (XPS) spectroscopy methods. The structure, morphology, and the crystalline phase of resulting Nd-(Fe1-xCox)-B oxide magnetic particles were characterized by Rietveld refinement of X-ray diffraction (XRD) patterns, scanning electron microscopy ( SEM), and high-resolution transmission electron microscopy (HR-TEM) and its selected area electron diffractograms (SAED). The results obtained from the Rietveld refinement of XRD patterns show that (Fe2O3/Fe3O4) phase ratio decreases with the amount of cobalt that can be attributed to the reduction of enthalpy . The SEM micrographs indicate that the oxide particles have an elongated structure with irregular shapes supported by TEM observations. The results of structural analysis by HR-TEM and SAED are consistent with the Rietveld results which confirms the presence of different oxide phases in Nd-(Fe1-xCox)-B oxide particles. The magnetic behaviorstudied by VSM was interpreted by the variances of the morphology, structure and chemical composition of Nd-(Fe1-xCox)-B oxide particles, all of which were influenced by the cobalt content. First‐Order Reversal Curve (FORC) diagrams show that the magnetic interaction between oxide particles decreases as the cobalt content increases.

Effect of High Pressure Treatment on Structural, Functional, and In‐Vitro Digestibility of Starches from Tubers, Cereals, and Beans

AbstractStarch from different sources (wheat, rice, corn, waxy corn, potato, sweet potato, and kidney bean) are subjected to high pressure treatment (HPT) at 300 and 600 MPa and are evaluated for changes in digestibility, structural, thermal, and pasting properties. HPT alters the surface of starch granules and significantly disrupts morphology of granules. Increase in average granule size and decrease in relative crystallinity is observed in high pressure treated starches. However, a significant decrease average granule size is observed at 600 MPa. High pressure treated starches show progressive reduction in both swelling power and solubility with increase in pressure. HPT results in reduction in gelatinization temperatures and enthalpy of gelatinization (ΔHgel) while starches except potato starch treated at 600 MPa do not show any endothermic peak indicating complete destruction of crystalline structure. Peak and final viscosity of native starches is higher than those of their counterpart high pressure treated starches except waxy corn starch. Increase in gel firmness and destruction of internal structure of starches especially that of tuber starches treated at high pressures is observed. HPT lowered rapidly digestible starch fraction and increased slowly digestible starch and resistant starch fraction.

The Effect of Dialkyl Peroxide Crosslinking on the Properties of LLDPE and UHMWPE.

Peroxide has been considered a chemical agent that can be used to tune the properties of polymeric materials. This research evaluated the influence of different concentrations of dialkyl peroxides on the mechanical, thermal, and morphological properties of linear low-density polyethylene (LLDPE) and ultra-high molecular weight polyethylene (UHMWPE). The neat polymer, as well as those with the addition of 1% and 2% by mass of dialkyl peroxides, were subjected to compression molding and immersion in water for 1 h, under controlled temperatures of 90 °C. The values of the gel content found in the samples indicated that the addition of peroxide to the LLDPE and to the UHMWPE promoted the formation of a reticulated network. The structure obtained by the crosslinking led to less reorganization of the chains during the crystallization process, resulting in the formation of imperfect crystals and, consequently, in the reduction in melting temperatures, crystallization and enthalpy. The mechanical properties were altered with the presence of the crosslinker. The polymers presented had predominant characteristics of a ductile material, with the occurrence of crazing with an increased peroxide content.

Non-intuitive Behavior of Polymer-Ciprofloxacin Nanoconjugate Suspensions: a Tool for Flexible Oral Drug Delivery.

Ciprofloxacin (CPX) is prone to spontaneous self-aggregation and formation of supramolecular dimers (π - π stacking) due to its complicated surface chemistry which has been associated with its anomalous solubility and instability in aqueous systems particularly near neutral pH. The surface characteristic of ciprofloxacin was modified through non-intuitive counterion interaction between CPX and diethylaminoethyl dextran (DDEX) to form nanoconjugate assembly. The CPX-DDEX nanoconjugate was confirmed by FTIR, SEM, DSC, TGA, and 1H-NMR. The DSC thermograms showed a remarkable 20% reduction in the melting temperature (Tm) of CPX from 268.57±1.11°C to 214.36±1.0211°C and 78% reduction in enthalpy of fusion (ΔHf) from 59.84 kJ/mol (180.59 J/g) to 12.90 kJ/mol (38.92 J/g), indicating increased solubility and dissolution efficiency. DDEX polymer alone exhibited pseudoplastic characteristics however with more viscous rather than elastic response, while the CPX-DDEX nanoconjugate suspensions exhibited remarkable elastic behavior with significantly increased storage modulus (G') thus controlling and extending the release of CPX. The reconstituted freeze-dried CPX-DDEX nanoconjugate suspension was chemically stable throughout the 90-day study both in the refrigerator and at controlled room temperature, while the aqueous suspension of pure CPX without DDEX was only stable for 72 and 24 h, respectively. The dissolution efficiency of the CPX-DDEX nanoconjugate suspensions increased with increasing molar concentration of DDEX to a maximum of 100% at 50 μM of DDEX followed by a remarkable decrease within the 3-week study. It was apparent that the dissolution efficiency was governed by a critical balance between the CPX solubility and the viscoelastic characteristics of the polymeric nanoassembly. This study demonstrates the potential application of polymer-drug nanoconjugation formulation design to stabilization and flexible delivery of CPX from aqueous suspension systems. Graphical abstract.

Macro-encapsulated 3D phase change material: Na2S2O3·5H2O-NaOAc·3H2O/carbonized Melamine sponge composite as core and SiC modified polyurethane thin-layer as shell

Micro-encapsulated phase change materials (PCMs) which constructed by PCMs as core and polymer as shell had been confirmed a good way to store and release latent heat, but its complex and expensive manufacturing process as well as poor mechanical strength impede its industrialization. Herein, based on the concept of micro-encapsulated PCM with core-shell structure, we conveniently prepared a 3D macro-encapsulated PCM with improved heat conductivity and mechanical performance. The optimized eutectic PCM with 72 wt%Na2S2O3·5H2O-28 wt%NaOAc·3H2O was impregnated into lightweight marco-porous carbonized Melamine sponge (CMS) carrier to prepare PCM@CMS composite as core, with pretty small enthalpy reduction within 1.23 %. Subsequently, SiC modified polyurethane thin-layer (PUSiC) was employed as shell to macro-encapsulate PCM@CMS, which solved leakage problem, improved thermal conductivity and guaranteed the steady function of PCM. The crystalline structure, composition and the morphology of PCM@CMS were analyzed in detail. Mechanical performance test revealed that PUSiC thin-layer possessed increased compression strength, tensile modulus and reduced fracture tensile strain, enabling the stable operation of PCM@CMS@PUSiC in high-intensity workplaces. Heat transfer experiment demonstrated that heat transfer of PCM@CMS@PUSiC was enhanced from the inside out. Thermal stability tests manifested the brilliant encapsulation effect of PUSiC thin-layer, by which PCM functioned steadily at 60 °C without leakage or dehydration. Furthermore, its thermal properties difference before and after 200 thermal cycles was small, showing a potential of long-time use.

Thermodynamics of CO2 adsorption on cellulose‐derived biochar prepared in ionic liquid

AbstractThis work focused on thermodynamic analysis of carbon dioxide (CO2) adsorption on a promising biochar as a CO2 adsorbent. The biochar was prepared by catalytic pyrolysis of cellulose material in ionic liquid at moderate temperature. The adsorption characteristics, such as adsorption capacity, interfacial potential, Gibbs free energy change, enthalpy change, entropy change, and internal energy change, influenced by adsorption temperature and gas pressure, were systematically investigated. The results indicated that CO2 adsorption on cellulose‐derived biochar was a spontaneous, physical, exothermic, and entropic decrement process, accompanied by adsorption capacity of 5.2 mmol/g and interfacial potential of −18.2 J/g at 273 K and 100 kPa. The process could be well described by adsorption potential theory. Then a quasi‐Gaussian distribution of site energy was verified for CO2 adsorption. The interfacial potential was found to be a monotropic function of the amount of CO2 adsorbed, and the latter was actually a differential of the former via adsorption potential. The positive temperature effect and negative pressure effect on negative Gibbs free energy change indicated that reducing adsorption temperature and increasing gas pressure were beneficial to CO2 uptake, accompanied by the increase of adsorption capacity and the reduction of interfacial energy, entropy, enthalpy, and internal energy. The strongest temperature effects on entropy change, enthalpy change, and internal energy change existed at given pressure or temperature. The pressure effect was stronger and more sensitive to pressure at lower adsorption pressure. More interestingly, the peak pressure or peak temperature with the strongest pressure effect possibly existed during CO2 adsorption.

Balancing processing ease with combustion performancein aluminum/PVDF energetic filaments

Molecular weight (Mw) effects in poly(vinylidene fluoride) (PVDF) influence both processability and combustion behavior in energetic Al–PVDF filaments. Results show decreased viscosity in unloaded and fuel-lean (i.e., 15 wt% Al) filaments. In highly loaded filaments (i.e., 30 wt% Al), reduced viscosity is minimal due to higher electrostatic interaction between Al particles and low Mw chains as confirmed by Fourier-transform infrared spectroscopy. Thermal and combustion analysis further corroborates this story as exothermic activity decreases in PVDF with smaller Mw chains. Differential scanning calorimetry and Thermogravimetric analysis show reduced reaction enthalpy and lower char yield in low Mw PVDF. Enthalpy reduction trends continued in nonequilibrium burn rate studies, which confirm that burn rate decreases in the presence of low Mw PVDF. Furthermore, powder X-ray patterns of post-burn products suggest that low Mw PVDF decomposition creates a diffusion barrier near the Al particle surface resulting in negligible AlF3 formation in fuel-rich filaments.

Mechanical and tribological properties evaluation of plasma-sprayed shape memory alloy coating

In the current investigation, an elemental blending of equiatomic Ni and Ti powder was considered to spray on mild steel by the atmospheric plasma spray process. The results revealed that the coating developed with 120 mm stand-off distance (SOD) has better mechanical properties such as microhardness and adhesion strength. Again, SOD predominantly influences the formation of intermetallics (NiTi, Ni3Ti, Ti2Ni, and TiO) that helps to enhance the microhardness (683.85 HV) as well as the mechanical interlocking and chemical bonding that is solely responsible for the high adhesion strength (43.17 MPa) of the coating. The failure analysis of the coating developed at too high and too low SOD revealed that rapid expansion of gas stream, reduction in enthalpy of particles, improper heat transfer, burning of splat, agglomeration of particles during flight, and oxidation are the key factors responsible for the reduction in mechanical properties of plasma-sprayed Ni-Ti alloy (NITINOL) coatings. In addition to the above, the solid particle erosion analysis revealed the increase in brittleness of the coating with increasing in SOD. The surface morphologies of the eroded surface depict various erosion mechanisms at both 45° and 90° impingement angles such as chip formation, lip formation, plastic deformation, scratches, etc.

Polyurethane macro-encapsulation for CH3COONa·3H2O-Na2S2O3·5H2O/Melamine sponge to fabricate form-stable composite phase change material

Using nano-sized porous supporting materials as carriers to shape-stabilize phase change materials (PCMs) is leading currently. However, the high carrier proportion and the existence of “nonfreezing liquid layer” in the composite significantly reduce the phase change enthalpy of composite. In this work, macroporous Melamine sponge (MS) as lightweight semi-adsorbed supporting material and the eutectic hydrated salt of Na2S2O3·5H2O-CH3COONa·3H2O as PCM were introduced, and the enthalpy reduction of the PCM@MS composite was much smaller (within 5%). Subsequently, the solid polyurethane (PU) thin-layer was adapted to macro-encapsulate PCM@MS, by which PCM operated stably in a closed system, solving the leakage problem and eliminating salt corrosion. With the addition of 2% SrCl2·6H2O as nucleating agent, the eutectic hydrated salt PCM with the mass ratio of 72%Na2S2O3·5H2O-28%CH3COONa·3H2O processed a suitable melting point (41.45 °C), high enthalpy (186.6 J/g) and low supercooling (0.462 °C). The morphology of MS and the distribution of PCM in MS were investigated in detail. Leakage and thermal stability tests for PCM@MS@PU indicated that 2.5 mm PU thin-layer owned a prominent cladding effect on PCM@MS. Heat conductivity determination manifested that PCM@MS@PU presented a brilliant thermal insulation property. Moreover, its thermal performance difference was small after 150 thermal cycles. All these enable the application of PCM@MS@PU in radiant floor heating system and provide a new routine for shape-stabilizing PCMs with polymer-based macroporous supporting material and thin-coating material.

Impact of high-intensity ultrasound waves on structural, functional, thermal and rheological properties of rice flour and its biopolymers structural features

Physical modifications of flours are an environment-friendly technology receiving increasing attention for widening the range of utilization of these raw materials. Rice flour was modified with ultrasound treatments at a frequency of 24 kHz and varying treatment time (2–60 min) and flour concentration (5–30%) in the dispersion. The effect of the modification was measured in the flours' physical, functional, pasting and rheological properties. Particle size of treated samples was reduced, and particle's disruption was observed by SEM; this had an impact on the water absorption ability, as shown by a sharp increase of swelling power. The thermal properties showed a significant reduction of gelatinization enthalpy, as well as narrowing of the gelatinization temperature range, characteristic of better packed starch crystalline structures after sonication. Modified patterns in starch and proteins were obtained with XRD and FTIR, which indicated impact to their crystalline and amide I secondary structures as a consequence of ultrasonication. Pasting profiles were found to be reduced with increasing treatment time, while higher concentrations did not significantly change the modification achieved. The pasting temperature was found to be significantly increased in all treated samples. Ultrasound treatment led to gels with higher strength, obtaining lower values of tan δ with increasing sonication time and flour concentration. Ultrasound allowed the modulation of rice flour functionality, being the effect independent on the concentration of the treated flour dispersion, up to 30%, and increased by treatment time up to 10 min; for longer treatments not many differences were found.

Formulation and characterization of artemether-loaded sodium alginate microcapsules

Purpose: To increase the solubility of artemether (ART) in Transcutol® HP through microencapsulation in sodium alginate polymer to achieve sustained in vivo release.Method: Graded concentrations of ART (0.00, 0.25, 0.50, 0.75, and 1.00 g) microcapsules were produced using Tween® 80 by the cold homogenization method at 24 x 1000 rpm for 15 min. Characterization based on yield, encapsulation efficiency (EE), particle size, pH stability, differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and in vivo release using Peter’s four-day suppressive protocol in Wistar mice infected with Plasmodium berghei, were determined.Results: The results obtained indicate that 0.5 g ART-loaded microcapsules (AMC) showed the highest yield of 96.85 %. The EE of 88.3 % corresponded to 0.75 g ART-loaded microcapsules. DSC results revealed that there was a significant reduction in enthalpy in all the formulations compared to the crystalline drug, but no strong bond interaction occurred except for the blank microcapsules. The AMC1.0 showed high dose-dependent plasmodial growth inhibition of 88.75 % while AMC0.25 had the least (68.13 %).Conclusion: The artemether microcapsules showed sustained release characteristics for oral delivery of artemether and therefore may reduce some of the adverse effects associated with high dose artemether therapy in conventional oral tablets.
 Keywords: Malaria, Artemether, Transcutol® HP, Sustained-release, RBC count, Antiplasmodial activity

Effect of acetylated starch on the development of peanut skin-cassava starch foams

Cassava starch was modified by acetylation to obtain modified starches with a degree of substitution (DS) of 0.5 and 1.5. The acetylated cassava starches presented a reduction in temperature gelatinization and enthalpy, water solubility, and power swelling, in addition to a loss of crystallinity compared to native cassava starches. Acetylated cassava starch was used to the development of foams based on native cassava starch, 24% (w/w) of peanut skin, and 13% (w/w) of glycerol. It was used blends of native cassava starch and acetylated cassava starch with ratios of 100/0, 90/10, 80/20, 70/30, and 60/40. The foams containing acetylated cassava starch with DS = 0.5 exhibited a reduction in water absorption capacity (WAC) for water contact time of 30 min. Foams containing acetylated cassava starch with DS = 1.5 did not show a significant difference in WAC compared to foams made using only native cassava starch. The use of 30% (w/w) of acetylated cassava starch, independently of DS (0.5 or 1.5), resulted in faster degradation of foams than those without modified starches.

Robust, 3D-printed hydratable plastics for effective solar desalination

In this work, hydratable plastics is being introduced as a new class of materials for effective solar desalination for the first time. In the form of highly amorphous regenerated cellulose, the 3D-printed material achieves a high evaporation rate of 3.01 kg m−2 h−1 under 1-sun irradiation through vaporisation enthalpy reduction. In addition, this work demonstrates that evaporation rate saturation at higher irradiation can be overcome by improving rehydration rate through architectural design via 3D-printing. As such, an unprecedented evaporation rate of 7.35 kg m−2 h−1 under concentrated 3-sun irradiation was achieved. More importantly, water molecules are found to be more locally ordered, leading to more hydrogen bonding in the hydrated cellulose than in bulk. It turns out that the weaker cellulose-water hydrogen bonds with longer bond length and higher deviation from non-linearity is the most probable origins for the significant reduction of vaporisation enthalpy. The 3D-printed evaporators also exhibits long-term stability and anti-salt-fouling ability in evaporating saline water due the interconnectivity of the micro and sub-nano water channels. Finally, purified water collected from a handmade device possess high drinkability.

Effects of drying temperature and genotype on morphology and technological, thermal, and pasting properties of corn starch

The objective of this study was to evaluate the effects of drying temperature (30, 50, 70, and 90 °C) and genotype (yellow floury corn, white floury corn, and yellow flint corn) on the morphology and technological and thermal properties of corn starch. The white and yellow genotypes with floury endosperm (soft) had spherical starch granules, while the granules of the yellow flint genotype were polyhedral. White floury corn showed higher extraction yield, higher resistance during granules' swelling before the physical collapse, as it was not affected by the increase in drying temperature, and at 90 °C it presented higher breakdown and energy necessary for gelatinization. There were peak viscosity and gelatinization enthalpy reduction on starch from yellow floury corn and yellow flint corn according to the increase in drying temperature. Drying temperatures below 50 °C are indicated for all genotypes studied. White floury corn is indicated due to the higher extraction yield presented. Yellow floury corn is indicated for application in chilled and frozen products due to lower starch retrogradation. The yellow flint corn is indicated for application as a thickening agent due to higher gel hardness.

Balancing processing ease with combustion performance in aluminum/PVDF energetic filaments

Abstract

Experimental Study on GNP Based Nanofluid Phase Change Material for Cooling Application

The current study aims to analyze the solidification and melting characteristics of nanofluid phase change material (NFPCM) for building cooling applications. The NFPCM were prepared by using graphene nanoplatelets (GNP) in different concentrations (0.2, 0.4 & 0.6 Wt. %) and DI water as base PCM. The NFPCM was prepared using two step methods and stability of the NFPCM was analyzed using visual sedimentation method. The experimentation was conducted in -12 °C and -9 °C surrounding bath temperatures. The Sub-cooling was eliminated completely for the addition of SDBS and GNP in maximum concentration. The experimental results showed that the 10 % and 8.5 % reduction in solidification time for 0.6 wt. % GNP in base PCM for the surrounding bath temperature of -12 °C and -9 °C respectively. Also, the DSC analysis was conducted for the heating rate of 5 K/min and the reduction of enthalpy during heating and cooling was noticed 14 % and 11 % respectively. It is observed that the reduction of overall solidification time of the NFPCM will have the predominant effect in the chiller operation time.

Sustainable Wood-Based Hierarchical Solar Steam Generator: A Biomimetic Design with Reduced Vaporization Enthalpy of Water.

Water purification by solar distillation is considered a promising technology for producing clean water from undrinkable water resources. A solar steam generator is a central part of a solar distillation process to separate water and contaminants. Here, we report an efficient and sustainable hierarchical solar steam generator (HSSG) with reduced vaporization enthalpy based on bacterial cellulose (BC) nanocomposites. The nanomaterials are assembled with BC nanofibers produced by bacteria in situ to form nanocomposites. Using this method, we construct functional BC nanocomposites inside and on the natural porous structure of wood. Our HSSG integrates solar-to-vapor efficiency improvement and vaporization enthalpy reduction by integrating the hierarchical multifunctional BC nanocomposites with the natural porous structure of wood. Because of the biomimetic design, hierarchical structure and reduced vaporization enthalpy of HSSG, a high evaporation rate of 2.9 kg m-2 h-1 and solar-to-vapor efficiency of 80% is achieved.

Parametric influence study of cryogenic hydrogen dispersion on theoretical aspect

In this paper, we proposed a theoretical model to study the dispersion of hydrogen. The model given a correlation between the concentration and temperature for cryogenic gases. The model based on adiabatic mixing hypothesis and neglected exterior heat sources, and thought the gas mixture was always at quasi-steady state. Real-gas law was adopted, and thermal physical properties of the gases are obtained from NIST REFPROP database. The concentration curve approximately appears a decreasing straight line, and turns on dew point and ice point, since heat released from water vapor phase change. Compared with liquid hydrogen and liquid natural gas spill experimental data, the model obtained well agreement solutions.Effects of three typical weather conditions (atmospheric temperature, relative humidity and barometric pressure) on hydrogen dispersion were quantitatively studied. It is confirmed that the dispersion is excited in summer, and is depressed in winter and transition seasons with increased ambient temperature. With increased ambient temperature, the effect of increased enthalpy reduction of the dry air components and the effect of the water latent heat are respectively dominate in the 268.15–293.15 K and 293.15–308.15 K ranges. Compared to ambient temperature and barometric pressure, relative humidity has the strongest positive effect on hydrogen dispersion, and the slight dampening effect of barometric pressure could be neglected.

Synthesis and Characterization of Nanostructured Lipid Nanocarriers for Enhanced Sun Protection Factor of Octyl p-methoxycinnamate.

Sunlight is important to health, but higher exposure to radiation causes early aging of the skin and skin damage that can lead to skin cancers. This study aimed at producing a stable octyl p-methoxycinnamate (OMC)-loaded nanostructured lipid carrier (NLC) sunscreen, which can help in the photoprotective effect. NLC was produced by emulsification-sonication method and these systems were composed of myristyl myristate (MM), caprylic capric triglyceride (CCT), Tween® 80 (TW), and soybean phosphatidylcholine (SP) and characterized by dynamic light scattering (DLS), zeta potential (ZP) measurement, atomic force microscopy (AFM), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and in vitro release studies. Pre-formulation studies were performed changing TW concentrations and no differences were found at concentrations of 1.0 and 2.0%. Two selected formulations were designed and showed an average size of 91.5-131.7, polydispersity index > 0.2, and a negative value of ZP. AFM presented a sphere-like morphology and SEM showed ability to form a thin film. DSC exhibited that the incorporation of OMC promoted reduction of enthalpy due to formation of a more amorphous structure. Drug release shows up to 55.74% and 30.57%, and this difference could be related to the presence of SP in this formulation that promoted a more amorphous structure; the release mechanism study indicated Fickian diffusion and relaxation. Sun protection factor (SPF) evaluation was performed using NLC and presented values around 40, considerably higher than those observed in the literature. The developed formulations provide a beneficial alternative to conventional sunscreen formulations.

CALB-catalyzed kinetic resolution of (RS)-3-benzoylthio-2-methylpropyl azolides: kinetic and thermodynamic analysis

Zofenopril as an ACE inhibitor expired recently was found to have a favourable safety profile in comparison with other ACE inhibitors in treating high blood pressure, congestive heart failure, and acute myocardial infarction. It can be synthesised from the key building blocks of (S)-3-benzoylthio-2-methylpropanoic acid and (4S)-phenylthio-L-proline. In this report, an efficient hydrolytic resolution via Candida antarctic lipase B (CALB) for preparing the former block in isopropyl ether (IPE) containing (RS)-3-benzoylthio-2-methylpropyl pyrazolide (1) and water was developed. Quantitative improvements of the enzyme activity and enantioselectivity in terms of k2SKmS−1 = 5.726 L h−1 g−1 and E = 217 at 45 °C were found from the kinetic analysis. Insights into the CALB performance via thermodynamic analysis were then addressed and compared with those by using (RS)-3-benzoylthio-2-methylpropyl 1,2,4-triazolide (2) as the substrate. A putative thermodynamic model was moreover hypothesised for elucidating the more enthalpy reduction of 68.92-70.86 kJ mol−1 from the acyl part of (S)-1 and (S)-2 as well as that of 23.69-25.63 kJ mol−1 from the triad imidazolium to Ser105 and leaving 1,2,4-triazole moiety of (R)-2 and (S)-2 on stabilising the corresponding transition states.