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31.
《International Journal of Hydrogen Energy》2022,47(36):16121-16131
Ammonia is considered as a promising hydrogen or energy carrier. Ammonia absorption or adsorption is an important aspect for both ammonia removal, storage and separation applications. To these ends, a wide range of solid and liquid sorbents have been investigated. Among these, the deep eutectic solvent (DES) is emerging as a promising class of ammonia absorbers. Herein, we report a novel type of DES, i.e., metal-containing DESs for ammonia absorption. Specifically, the NH3 absorption capacity is enhanced by ca. 18.1–36.9% when a small amount of metal chlorides, such as MgCl2, MnCl2 etc., are added into a DES composed of resorcinol (Res) and ethylene glycol (EG). To our knowledge, the MgCl2/Res/EG (0.1:1:2) DES outperforms most of the reported DESs. The excellent NH3 absorption performances of metal–containing DESs have been attributed to the synergy of Lewis acid–base and hydrogen bonding interactions. Additionally, good reversibility and high NH3/CO2 selectivity are achieved over the MgCl2/Res/EG (0.1:1:2) DES, which enables it to be a potential NH3 absorber for further investigations. 相似文献
32.
《International Journal of Hydrogen Energy》2022,47(67):29172-29183
To improve the safety of wet dust removal systems for processing magnesium-based alloys, a new method is proposed for preventing hydrogen generation. In this paper, hydrogen generation by Mg–Zn alloy dust was inhibited with six common metal corrosion inhibitors. The results showed that sodium dodecylbenzene sulfonate was the best hydrogen inhibitor, while CeCl3 enhanced hydrogen precipitation. The film-forming stability of sodium dodecylbenzene sulfonate was tested with different contents, temperatures, Cl? concentrations and perturbation rates. The results showed that this inhibitor formed stable protective films on the surfaces of Mg–Zn alloy particles, and adsorption followed the Langmuir adsorption model. 相似文献
33.
Xinyao Xie Xiaoqiong Wang Xiufang Bi Nan Ning Mingyuan Li Yage Xing Zhenming Che 《International Journal of Food Science & Technology》2022,57(7):4368-4379
This study investigated the effect of ultrafiltration (UF) combined with high-pressure processing (HPP) at 550 MPa, 25 °C for 5 min, ultrasound (US) at 520 W, 40 °C for 10 min and heat treatment (HT) at 90 °C for 3 min on the microbial, physicochemical and sensory properties of a blueberry–grape–pineapple–cantaloupe juice blend during 104 days of storage at 4 °C. After UF, the shelf life of the HPP- and US-treated clear juice blends were 104 and 72 days during the storage at 4 °C respectively. HPP, US and HT treatment minimally affected the anthocyanin and total phenol contents, while HPP better maintained the ascorbic acid levels and sensory properties in the clear juice blend during the storage. Therefore, HPP combined with UF was identified as a prospective processing technique in the fruit juice industry. 相似文献
34.
Referring to the total surface existing in wheat dough, gluten–starch interfaces are a major component. However, their impact on dough rheology is largely unclear. Common viewpoints, based on starch surface modifications or reconstitution experiments, failed to show unambiguous relations of interface characteristics and dough rheology. Observing hybrid artificial dough systems with defined particle surface functionalization gives a new perspective. Since surface functionalization standardizes particle–polymer interfaces, the impact on rheology becomes clearly transferable and thus, contributes to a better understanding of gluten–starch interfaces. Based on this perspective, the effect of particle/starch surface functionality is discussed in relation to the rheological properties of natural wheat dough and modified gluten–starch systems. A competitive relation of starch and gluten for intermolecular interactions with the network-forming polymer becomes apparent during network development by adsorption phenomena. This gluten–starch adhesiveness delays the beginning of non-linearity under large deformations, thus contributing to a high deformability of dough. Consequently, starch surface functionality affects the mechanical properties, starting from network formation and ending with the thermal fixation of structure. 相似文献
35.
《International Journal of Hydrogen Energy》2022,47(25):12569-12581
Heteroatomic doping is an effective way to optimize the electronic structure of carbon nitride to boost photocatalytic performance. However, the extra introduced defects could result in the decrease of its crystallinity. In this work, crystalline K–I co-doped carbon nitride (K–I–CCN) was simply synthesized from molten salt ionthermal post-calcination in nitrogen atmosphere. Structure characterization results indicate that compared to K–CCN synthesized from conventional molten salt heat treatment in air, nitrogen heating atmosphere is more conductive for the formation of homogeneous pore structure of the catalyst, which has larger surface area and pore volume, while could repairing some defects and resulting in better polymerization crystallization. In addition, except the implanting of K, I doping is still retained after nitrogen heat treatment, thus forming K–I co-doping structure. Due to the positive charge effect of K–I co-doping, K–I–CCN has a narrower band gap, higher surface charge density and stronger charge transport, so it performs significantly enhanced photocatalytic H2 evolution activity from water splitting. 相似文献
36.
Najiba Hasan Hamad 《亚洲传热研究》2022,51(5):3794-3814
Classical Fourier's theory is well-known in continuum physics and thermal sciences. However, the primary drawback of this law is that it contradicts the principle of causality. To explore the thermal relaxation time characteristic, Cattaneo–Christov's theory is adopted thermally. In this regard, the features of magnetohydrodynamic (MHD) mixed convective flows of Casson fluids over an impermeable irregular sheet are revealed numerically. In addition, the resulting system of partial differential equations is altered via practical transformations into nonlinear ordinary differential equations. An advanced numerical algorithm is developed in this respect to get higher approximations for temperature and velocity fields, as well as their corresponding wall gradients. For validating our numerical code, the current outcomes are compared with the available literature results. Moreover, it is revealed that the velocity field is more prominent in the suction flow situation as compared with the injection flow case. It is also found that the Casson fluid is hastened in the case of lower yield stress. Larger values of thermal relaxation parameters create a lessening trend in the temperature distribution and its related boundary layer breadth. 相似文献
37.
《Ceramics International》2022,48(9):12585-12591
In this study, zinc oxide (ZnO) nanofibers were prepared using the electrospinning method, and the effects of different spinning voltages and annealing temperatures on the fiber structure were tested. La0.8Sr0.2FeO3 (LSFO) perovskite film was prepared by a sol-gel method. Then we dip LSFO on ZnO nanofiber and grow it on the interdigital gold electrode substrate for gas sensors. The results show that the ZnO/LSFO heterostructure gas sensor has a good sensing response to H2S gas and exhibits good gas selectivity. The best gas response is 52.17% under 4 ppm H2S and work temperature 200°C, which has good recovery and reproducibility. 相似文献
38.
《Ceramics International》2022,48(17):24346-24354
The borided layer was prepared on the surface of the Ti–5Mo–5V–8Cr–3Al alloy by powder-pack boriding at 1000°C-10h. SEM, EPMA and TEM were used to investigate the effects of alloying elements (Al, V, Mo and Cr) on the growth of TiB whiskers in the borided Ti–5Mo–5V–8Cr–3Al alloy. Wear properties of borided Ti–5Mo–5V–8Cr–3Al alloy were investigated using dry reciprocating friction tests. SEM results show that the thickness of boride layer in Ti–5Mo–5V–8Cr–3Al alloy is thinner than that in the Cp-Ti. This is attributed to the enrichment of alloying elements especially V in TiB/substrate by TEM, which hinders the diffusion of B atoms, thus resulting in the short and thick TiB whiskers in Ti–5Mo–5V–8Cr–3Al alloy. Borided Ti–5Mo–5V–8Cr–3Al alloy has the better wear resistance than as-received alloy. 相似文献
39.
《International Journal of Hydrogen Energy》2022,47(65):27973-27985
Metal-support interaction and catalyst pretreatment are important for industrial catalysis. This work investigated the effect of supports (SiO2, CeO2, TiO2 and ZrO2) for Cu–Pd catalyst with high Cu/Pd ratio (Cu/Pd = 33.5) regarding catalyst cost, and the reduction temperatures of 350 °C and 550 °C were compared. The activity based on catalyst weight follows the order of Si > Ce > Zr > Ti when reduced at 350 °C. The reduction temperature leads to the surface reconstruction over the SiO2, CeO2 and TiO2 catalysts, while results in phase transition over Cu–Pd/ZrO2. The effect of reduction temperature on catalytic performance is prominent for the SiO2 and ZrO2 supported catalysts but not for the CeO2 and TiO2 ones. Among the investigated catalysts, Zr-350 exhibits the highest methanol yield. This work reveals the importance of the supports and pretreatment conditions on the physical-chemical properties and the catalytic performance of the Cu–Pd bimetallic catalysts. 相似文献
40.
《International Journal of Hydrogen Energy》2022,47(92):39030-39046
Significant efforts have been made to develop highly active non-noble metal-based, affordable metallic and stable electro-catalysts for hydrogen evolution reaction (HER). Strong acid and bases are now used in HER operations to achieve large-scale, sustained H2 fuel production. However, few studies have utilized phosphate-buffered neutral electrolytes (PBS) in the field of neutral electrolyte technology. In this work, a certain alloys with a Ni–Cr basis have been produced as favorable components for the HER under neutral conditions. Additionally, the current investigations are emphasizing on the concentration of buffer phosphate species in the HER activity of various materials. By employing polarization and electrochemical impedance spectroscopy (EIS) in neutral solutions, the electro-catalytic activity of new alloys on HER was evaluated. According to the preliminary findings, the examined Ni–Cr-based alloys show superior HER catalytic activity in neutral electrolytes. Additionally, the Ni–Cr alloy matrix with Fe and Mo added enhances HER electrocatalytic efficiency while lowering interfacial charge transfer resistance. Due to its low overpotential of ?297 mV @ 10 mA cm?2 and Tafel slope of 94 mV dec?1 in 1.0 M PBS media, the Ni–Cr–Mo–Fe alloy exhibits an efficient HER, suggesting that the Ni–Cr–Mo–Fe electrode will be a potential noble metal-free electro-catalyst for HER. The Ni–Cr–Mo–Fe cathode is a readily available and affordable material for the production of HER in neutral medium. 相似文献