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Gelatin methacryloyl (GelMA) is one of the most widely used photo-crosslinkable biopolymers in tissue engineering. In in presence of an appropriate photoinitiator, the light activation triggers the crosslinking process, which provides shape fidelity and stability at physiological temperature. Although ultraviolet (UV) has been extensively explored for photo-crosslinking, its application has been linked to numerous biosafety concerns, originated from UV phototoxicity. Eosin Y, in combination with TEOA and VC, is a biosafe photoinitiation system that can be activated via visible light instead of UV and bypasses those biosafety concerns; however, the crosslinking system needs fine-tuning and optimization. In order to systematically optimize the crosslinking conditions, we herein independently varied the concentrations of Eosin Y [(EY)], triethanolamine (TEOA), vinyl caprolactam (VC), GelMA precursor, and crosslinking times and assessed the effect of those parameters on the properties the hydrogel. Our data showed that except EY, which exhibited an optimal concentration (~ 0.05 mM), increasing [TEOA], [VA], [GelMA], or crosslinking time improved mechanical (tensile strength/modulus and compressive modulus), adhesion (lap shear strength), swelling, biodegradation properties of the hydrogel. However, increasing the concentrations of crosslinking reagents ([TEOA], [VA], [GelMA]) reduced cell viability in 3-dimensional (3D) cell culture. This study enabled us to optimize the crosslinking conditions to improve the properties of the GelMA hydrogel and to generate a library of hydrogels with defined properties essential for different biomedical applications.

The effect of sacrificial reagents (SRs) on photocatalytic H 2 evolution rate over different photocatalysts was systematically studied. Zn 0.5 Cd 0.5 S, graphitic carbon nitride (g-C 3 N 4 ), and TiO 2 were chosen as typical photocatalysts, while alcohols, amines, carboxylic acids, and inorganic Na 2 S/Na 2 SO 3 were chosen as SRs. The results indicate that Na 2 S/Na 2 SO 3 , methanol, and triethanolamine are the most suitable SRs for Zn 0.5 Cd 0.5 S, TiO 2 , and g-C 3 N 4 , respectively. It was found that in selecting organic SRs, both the permittivity and oxidation potential have profound effects on the H 2 production efficiency, which will provide basis for choosing appropriate SRs for different photocatalysts.

CuNi-BTC was synthesized using the co-precipitation method with precursors copper (II) nitrate trihydrate, nickel nitrate trihydrate, benzene-1,3,5-tricarboxylic acid, and the addition of 10 wt% triethanolamine (TEOA) as a modulator. The synthesis was conducted at room temperature and dried at 60°C for 24 hours. X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier-Transform Infrared (FTIR), Brunnauer-Emmet-Teller (BET), and electrochemical measurement are techniques employed for the characterization of the material. The diffraction patterns of CuNi-BTC show similar diffraction peaks of the HKUST-1 at 2θ of 6.7°, 9.5°, 11.5°, and 13.4°, respectively. The morphology of CuNi-BTC has an octahedral shape with a pore on its surface. The BET analyses show that the surface area of CuNi-BTC is 534 m 2 /g with pore and diameter volumes of 0.044 cm 3 /g and 1.60 nm, respectively. The nitrogen adsorption-desorption isotherm graph shows the type IV characteristic of a mesoporous material. The electrochemical performance of the material was observed by cyclic voltammetry (CV) methods. The CuNi-BTC has current reduction and oxidation values of 4.46 and 3.38 μA, respectively, and has good stability at various scan rates between 10 – 100 mvs -1 .

Photocatalytic water splitting is a sustainable technology for the production of clean fuel in terms of hydrogen (H2). In the present study, hydrogen (H2) production efficiency of three promising photocatalysts (titania (TiO2-P25), graphitic carbon nitride (g-C3N4), and cadmium sulfide (CdS)) was evaluated in detail using various sacrificial agents. The effect of most commonly used sacrificial agents in the recent years, such as methanol, ethanol, isopropanol, ethylene glycol, glycerol, lactic acid, glucose, sodium sulfide, sodium sulfite, sodium sulfide/sodium sulfite mixture, and triethanolamine, were evaluated on TiO2-P25, g-C3N4, and CdS. H2 production experiments were carried out under simulated solar light irradiation in an immersion type photo-reactor. All the experiments were performed without any noble metal co-catalyst. Moreover, photolysis experiments were executed to study the H2 generation in the absence of a catalyst. The results were discussed specifically in terms of chemical reactions, pH of the reaction medium, hydroxyl groups, alpha hydrogen, and carbon chain length of sacrificial agents. The results revealed that glucose and glycerol are the most suitable sacrificial agents for an oxide photocatalyst. Triethanolamine is the ideal sacrificial agent for carbon and sulfide photocatalyst. A remarkable amount of H2 was produced from the photolysis of sodium sulfide and sodium sulfide/sodium sulfite mixture without any photocatalyst. The findings of this study would be highly beneficial for the selection of sacrificial agents for a particular photocatalyst.

Materials with viscoplastic characteristics have been widely studied due to their applicability in various industries, but also because they are common in nature. The flow curve of viscoplastic fluids is generally well-captured by the Herschel-Bulkley (HB) model, which can account for yield stress and has a power-law behavior after flow occurs. Carbopol solutions are the most common kind of fluids used in experimental studies involving viscoplastic behavior. Carbopol solutions generally need a neutralizing agent, which acts as a pH regulator and prevents the formation of fungus. However, this agent can also affect the rheological properties of the original solution. In this work, yield stress measurements from different techniques (flow curve, oscillatory, and creep tests) were conducted for a combination of Carbopol and triethanolamine (neutralizing agent) concentrations of aqueous solutions. In addition, pH measurements for all samples were performed. For the analyzed cases, it was found that triethanolamine concentrations must be higher than 500 ppm to avoid the formation of fungi but below 700 ppm to obtain a homogeneous solution. The yield stress was shown to increase with the increment in the concentration of both components. In a more fundamental analysis, we employed the Suspension of Fractal Aggregates (SoFA) model, conceived to represent waxy crude oils, to evaluate the system considered and found an accurate agreement with respect to the data. This result shows that there can be similarities between the dynamics of both aggregate structures, to be verified in future studies.

Using natural materials, i.e. halloysite nanoclay that is a biocompatible naturally occurring clay and Heracleum persicum extract that can serve as a green reducing agent, a novel magnetic catalyst, Fe 3 O 4 /Hal-Mel-TEA(IL)-Pd, has been designed and fabricated. To prepare the catalyst, halloysite was first magnetized (magnetic particles with mean diameter of 13.06 ± 3.1 nm) and then surface functionalized with melamine, 1,4 dibromobutane and triethanolamine to provide ionic liquid on the halloysite surface (5 wt%). The latter was then used as a support to immobilize Pd nanoparticles that were reduced by Heracleum persicum extract. The characterization of the catalyst established that the loading of Pd in Fe 3 O 4 /Hal-Mel-TEA(IL)-Pd was very low (0.93 wt%) and its specific surface area was 63 m 2 g −1 . Moreover, the catalyst showed magnetic property (Ms = 19.75 emu g −1 ) and could be magnetically separated from the reaction. The catalytic performance of the magnetic catalyst for reductive degradation of methyl orange and rhodamine B in the presence of NaBH 4 in aqueous media was investigated. The activation energy, enthalpy, and entropy for the reduction of methyl orange were estimated as 42.02 kJ mol −1 , 39.40 kJ mol −1 , and −139.06 J mol −1 K −1 , respectively. These values for rhodamine B were calculated as 39.97 kJ mol −1 , 34.33 kJ mol −1 , and −155.18 Jmol −1 K −1 , respectively. Notably, Fe 3 O 4 /Hal-Mel-TEA(IL)-Pd could be reused for eight reaction runs with negligible loss of the catalytic activity (~3%) and Pd leaching (0.01 wt% of the initial loading).

Wound healing is fundamental to restore the tissue integrity. A topical study of the influence of Aloe vera hydrogel, formulated with 1,2-propanediol (propanediol) and triethanolamine (TEA), on the skin wound-healing process was investigated in female Wistar rats. FTIR spectroscopy confirms the presence of carboxylic acid and methyl ester carboxylate groups related with important compounds that confer the hydrogel a good interaction with proteins and growth factors. SEM images show a microstructure and micro-roughness that promote a good adhesion to the wound. Therefore, the swelling kinetics and the contact angle response contribute to the understanding of the in vivo results of the animal test. The results indicated that the Aloe vera hydrogel, prepared with propanediol and TEA, together with its superficial characteristics, improve its rapid penetration without drying out the treated tissue. This produced a positive influence on inflammation, angiogenesis, and wound contraction, reducing 29% the total healing time, reaching the total closure of the wound in 15 days.

Here, the catalytic and degradation effect of nickel nanoparticles (NiNPs) on triethanolamine (TEA) with CO2 at 20 °C and 50 °C and a range of TEA concentrations (3–30 wt%) was studied. We show that TEA absorption rate of CO2 can be enhanced with NiNPs, the maximum enhancement was 8.3% when compared to a control solution found at 50 °C with 30 wt% TEA alone. Additionally, the time for TEA to be fully loaded with CO2 is reduced; compared to the control, NiNPs enhanced solutions were up to 26.3% faster. Also, to the best of our knowledge, this is the first time the degradation of TEA with NiNPs has been studied. TEA was subject to both oxygen (30 wt%, 55 °C, 0.35 L/min of air, 0.4 molCO2/molTEA, 7.5 mL/min of CO2) and thermal degradation with and without NiNPs (30 wt%, 0.5 molCO2/molTEA, 135 °C). In both degradation experiments, surprisingly, there was no significant difference in TEA degradation in the presence of NiNPs. At high temperature (135 °C), the solution lost 19.2% and 20.3% of the original TEA, with and without NiNPs, respectively. In the presence of oxygen, the solution lost 30.5% and 33.6% of the original TEA, with and without NiNPs, respectively. This indicates that TEA or its mixture with other amines and NiNPs could improve post-combustion CO2 capture.

Design and preparation of noble-metal-free photocatalysts is of great importance for photocatalytic water splitting harvesting solar energy. Here, we report the high visible-light-driven hydrogen evolution upon the hybrid photocatalyst system consisting of CdS nanocrystals and Ni@NiO nanoparticles grown on the surface of g-C 3 N 4 . The hybrid system shows a high H 2 -production rate of 1258.7 μmol h −1 g −1 in the presence of triethanolamine as a sacrificial electron donor under visible light irradiation. The synergetic catalytic mechanism has been studied and the results of photovoltaic and photoluminescence properties show that efficient electron transfer could be achieved from g-C 3 N 4 to CdS nanocrystals and subsequently to Ni@NiO hybrid.

The high specific surface area (SSA) mesoporous silica nanoparticles (MSNs) are synthesized and characterized in this work. The structure directing method combined with the co-condensation and bi-phasic processes are employed to fabricate the porous particles. Myristyltrimethylammonium bromide (MTAB) is utilized as the major structure directing agent. Triton X-100 and triethanolamine (TEA) are employed as the co-structure directing agents. In order to generate a bi-phasic environment and increase the reaction rate, cyclohexane (CHX) and L-Arginine (LAG) are used, respectively. To swelling of the structure directing agents, the solution of structure directing agents, solvent and catalyst is subjected to sonicate by ultrasonic wave with the frequency of 40 kHz. In the research, as synthesized sample of particles are characterized by different scientific techniques. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) are utilized to analyze the morphology and pore formed on the obtained particles. The N 2 adsorption-desorption isotherm testing integrated with the BET and BJH calculation techniques are employed to determine the SSA, mean pore diameter and total pore volume of the resultant particles at relative pressure of 0.99. Results from the tests as mentioned revealed that SSA of particles synthesized by using only MTAB as a structure directing agent, is about 672.30 m 2 /g while SSA of particles fabricated by using MTAB+TEA and MTAB+triton X-100 is 691.45 and 651.93 m 2 /g, respectively. A mean pore diameter and total pore volume of the obtained particles are 4.9, 7.5, 3.9 nm and 0.83, 1.30, 0.63 cm 3 /g when MTAB, MTAB+TEA and MTAB+X-100 are used as structure directing agents, respectively. Porous particles with uniform size distribution are successfully synthesized and confirmed by SEM and TEM micrographs, respectively. Finally, TEM-EDX confirmed that the synthesized particles are silica (SiO 2 ) nanoparticles.