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81.
Journal of Thermal Analysis and Calorimetry - This study shows multiple solutions, heat transfer characteristics, and stability analysis of the magnetohydrodynamic (MHD) flow of hybrid nanofluid...  相似文献   
82.
There are limited reports about the effect of different heat treatments on the quality and flavor of Black Tibetan sheep meat. The current study examined the effect of pan-frying, deep-frying, baking, and boiling treatment on the quality of Black Tibetan sheep meat; the amino acid, fatty acid, and volatile flavor compounds (VFCs) were investigated by a texture analyzer, ultra-high-performance liquid chromatography (UHPLC), gas chromatography (GC), and headspace-gas chromatography-ion mobility (HS-GC-IMS). The key VFCs were identified through orthogonal partial least squares discrimination analysis (OPLS-DA), and variable importance projection (VIP) values. In addition, Pearson’s correlations between meat quality parameters and key VFCs were examined. The sensory scores, including texture, color, and appearance, of baked and pan-fried meat were higher than those of deep-fried and boiled meat. The protein (40.47%) and amino acid (62.93 µmol/g) contents were the highest in pan-fried meat (p < 0.05). Additionally, it contained the highest amounts of monounsaturated and polyunsaturated fatty acids, such as oleic, linoleic, and α-linolenic acids (p < 0.05). Meanwhile, pan-fried and deep-fried meat had higher amounts of VFCs than baked meat. The OPLS-DA similarity and fingerprinting analyses revealed significant differences between the three heat treatment methods. Aldehydes were the key aroma compounds in pan-fried meat. Importantly, 3-methylbutyraldehyde and 2-heptanone contents were positively correlated with eicosenoic, oleic, isooleic, linoleic, α-Linolenic, and eicosadiene acids (p < 0.05). To sum up, pan-fried Black Tibetan sheep meat had the best edible, nutritional, and flavor quality.  相似文献   
83.
A T1ρ filter for the NMR imaging of solid polymers is presented. T1ρ is the relaxation time in the rotating frame, which is sensitive to the molecular motion and whose spectral density falls in the range of slow dynamics, namely motion characterized by correlation times ranging between 10−2 and 10−5 s. The method allows one to obtain a good spatial resolution without the need of strong field gradients and without the effects related to the spatial encoding manipulation of the spin system.  相似文献   
84.
We construct a simple CPA for studying ferromagnets which simultaneously possess site and (isotropic) exchange bond disorders. We use the theory to study spin-wave stiffness in diluted ferromagnet with exchange amorphousness and analyze the structure of the interfaces between ferromagnetic, spin-glass and paramagnetic phases of such a system.  相似文献   
85.
The present paper describes an effective and low-cost spectrophotometric method for the determination of mefenamic acid in its pure form and pharmaceutical preparations. The method is based on the charge-transfer complexation between mefenamic acid as an n-electron donor and chloranil as a π-acceptor to form a violet chromogen measured at 540 nm. Under the optimum conditions, a linear relationship with a good correlation coefficient (0.9996) was found between the absorbance and concentration of the studied drug in the range of 10–60 μg/mL. The optimal reaction conditions such as reagent concentration, heating time, and stability of the reaction product were determined. The limit of detection (LOD) was 2.16 μg/mL and the limit of quantifycation (LOQ) was 7.15 μg/mL. The method was successfully applied to the determination of mefenamic acid in pharmaceutical preparations without any interference from common excipients. The text was submitted by the author in English.  相似文献   
86.
Rechargeable Zinc batteries (RZBs) are considered a potent competitor for next-generation electrochemical devices, due to their multiple advantages. Nevertheless, traditional aqueous electrolytes may cause serious hazards to long-term battery cycling through fast capacity fading and poor Coulombic efficiency (CE), which happens due to complex reaction kinetics in aqueous systems. Herein, we proposed the novel adoption of the protic amide solvent, N-methyl formamide (NMF) as a Zinc battery electrolyte, which possesses a high dielectric constant and high flash point to promote fast kinetics and battery safety simultaneously. Dendrite-free and granular Zn deposition in Zn-NMF electrolyte assures ultra-long lifespan of 2000 h at 2.0 mA cm−2/2.0 mAh cm−2, high CE of 99.57 %, wide electrochemical window (≈3.43 V vs. Zn2+/Zn), and outstanding durability up to 10.0 mAh cm−2. This work sheds light on the efficient performance of the protic non-aqueous electrolyte, which will open new opportunities to promote safe and energy-dense RZBs.  相似文献   
87.
Cellulose - In this work we have attempted to use biomass as energy source which is abundantly available throughout the world. The work is focused on pyrolysis of sugarcane bagasse in a...  相似文献   
88.
In the current paper, through a convergent multi-step approach, a library of novel indole-phenyltriazole hybrids containing an amide moiety ( 9a-k) was synthesized. The structural verification of all synthesized molecules was accomplished by CHN and spectral analyses data. These synthesized bi-heterocyclic derivatives ( 9a-k ) were evaluated for their anti-ulcer potential by inhibitory action against Jack bean urease enzyme and subsequently their structure-activity relationship was perceived. Moreover, these compounds were inspected for cytotoxic profile by hemolytic activity and it was professed that nearly all the synthesized compounds showed low cytotoxicity. In addition, free radical scavenging activity and kinetic analysis were also carried out for these compounds to understand their mode of inhibition. So, it was summated that these derivatives might lead to further research gateways for obtaining better and safe anti-ulcer agents.  相似文献   
89.
A new tricyclic clerodane-type diterpenoid, trivially named phlomeoic acid (1), was isolated from the methanolic extract of Phlomis bracteosa, together with two known compounds, ursolic acid and glutinol, isolated for the first time from this species. Their structures were elucidated by means of spectroscopic and mass spectrometric techniques and comparison with literature data.  相似文献   
90.
We present a simple, novel procedure to selectively deposit gold nanoparticles using pure water. It enables patterning of nanoparticle monolayers with a remarkably high degree of selectivity on flat as well as microstructured oxide surfaces. We demonstrate that water molecules form a thin "capping" layer on exposed thiol molecules within the mercaptan self-assembled layer. This reversible capping of water molecules locally "deactivates" the thiol groups, therewith inhibiting the binding of metallic gold nanoparticles to these specific areas. This amazing role of water molecules can be used as a tool to pattern flat as well as structured surfaces with gold nanoparticles.  相似文献   
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