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921.
The advent of the Haber–Bosch (HB) process has made accessible all forms of nitrogenous derivatives (ammonia, nitrates, nitrites, and amines), revolutionizing the chemical industry. However, the depleting natural resources and growing environmental concerns demand a shift toward an energy-abated and environment-friendly alternative to the HB process, hence the shift in the recent research focus. The electrochemical reduction pathway offers one of the most alluring prospects as a carbon-free, environment-friendly, energy-abated alternative to the HB process. In this context, we provide a holistic overview of the electrochemical pathways for nitrogen fixation into its activated forms and categorically discuss the energetical and technological challenges that researchers encounter, simultaneously highlighting commendable contributions in the field. We also propose research targets that can serve as a benchmark to measure progress toward the practical realization of the electrochemical nitrogen reduction reaction. 相似文献
922.
Mohammad Nasir Uddin Md. Shaharier Amin Md. Saifur Rahman Sonia Khandaker Wahhida Shumi Md. Atiar Rahman Sheikh Mahbubur Rahman 《应用有机金属化学》2021,35(1)
Symmetrical bis‐Schiff bases (LH 2) have been synthesized by the condensation of 1,6‐hexanediamine (hn) and carbonyl or dicarbonyl. One of the synthesized Schiff bases has been subjected to the molecular docking for the prediction of their potentiality against coronavirus (SARS‐CoV‐2). Molecular docking revealed that tested Schiff base possessed high binding affinity with the receptor protein of SARS CoV‐2 compared with hydroxychloroquine (HCQ). The ADMET analysis showed that ligand is non‐carcinogenic and less toxic than standard HCQ. Schiff bases acting as dibasic tetra‐dentate ligands formed titanium (IV) complexes of the type [TiL(H2O)2Cl2] or [TiL(H2O)2]Cl2 being coordinated through ONNO donor atoms. Ligands and complexes were characterized by the elemental analysis and physicochemical and spectroscopic data including FTIR, 1H NMR, mass spectra, UV‐Visible spectra, molar conductance, and magnetic measurement. Optimized structures obtained from quantum chemical calculations supported the formation of complexes. Antibacterial, antifungal, and anti‐oxidant activity assessments have been studied for synthesized ligands and complexes. 相似文献
923.
Shahrajabian Hamzeh Bagherzadeh Seyed Amin Moghri Mehdi Karimi Vahid Jamali Mehdi 《Journal of Thermal Analysis and Calorimetry》2021,144(6):2099-2107
Journal of Thermal Analysis and Calorimetry - Doing experiments in order to determine mechanical properties of nanocomposites costs a lot. Therefore, finding the ways by which the properties of the... 相似文献
924.
Mohammad Foad Abazari Shohreh Zare Karizi Mina Kohandani Navid Nasiri Fatemeh Nejati Ehsan Saburi Amin Reza Nikpoor Seyed Ehsan Enderami Fatemeh Soleimanifar Vahid Mansouri 《先进技术聚合物》2020,31(10):2259-2269
Tissue engineering using new strategies has become a growing and promising method for treating large tissue lesions in the body. On the other hand, microRNAs (miRNAs), which are small non‐coding regulatory RNAs, are a new class of genetic materials that can have effective pharmacological roles. The combination of these two themes has created promising prospects for the treatment of diseases. Herein, human induced pluripotent stem cells (iPSCs) were transduced with miRNA‐2861 and then the osteogenic differentiation potential of transduced iPSCs and non‐transduced iPSCs was investigated while cultured on the electrospun poly lactic‐co‐glycolic acid (PLGA) nanofibrous scaffold and culture plate. MiR‐2861‐transduced iPSCs showed a significantly higher viability, mineralization, alkaline phosphatase (ALP) activity, calcium content, and bone‐related gene expression in comparison with those iPSCs that non‐transduced. The results also indicated that this increase is improved when miR‐2861 transduced iPSCs are cultured on the PLGA nanofibrous scaffold synergistically. This synergy was also confirmed by the results obtained from of Western blot analysis. It can be concluded that, miR‐2861, by negative regulation of those proteins that decrease/inhibit osteogenic differentiation and PLGA nanofibrous scaffold by preparation of a suitable artificial extracellular matrix, have a great positive impact in improving iPSCs osteogenic differentiation potential and this blend can be proposed to use in bone tissue engineering application. 相似文献
925.
In this work, the optoelectronic performance of organic/inorganic heterojunction photodiode based on alpha-sexithiophene (α-6T/n-Si) is introduced. A thin film of α-6T was deposited on the n-type silicon substrate by a thermal evaporation technique. The topographical properties of the α-6T thin film grown on the n-Si substrate were investigated using a field emission scanning electron microscope (FESEM) technique. A network of nanocrystalline needles over the film surface was observed which give rise to an improvement in the electric charge transport. The optical properties of the prepared thin film were investigated using a spectrophotometric technique. The high absorption of α-6T in UV and visible region suggested the ability of this architecture for UV and visible light detection. The I-V characteristics of the fabricated photodiode were investigated in dark and under different illumination intensities and different wavelengths. The present architecture showed a good response to halogen lamb light, where the estimated values of rising and falling time at 160 mW/cm2 were about 400 ms and 450 ms, respectively. The results show the possibility of using Au/α-6T/n-Si/Al structure as a photodetector for a wide range of the solar spectrum (UV–Visible). 相似文献
926.
Glucose 2-oxidase (pyranose oxidase, pyranose:oxygen-2-oxidoreductase, EC 1.1.3.10) from Coriolus versicolor catalyses the oxidation of d-glucose at carbon 2 in the presence of molecular O2 producing d-glucosone (2-keto-glucose and d-arabino-2-hexosulose) and H2O2. It was used to convert d-glucose into d-glucosone at moderate pressures (i.e. up to 150 bar) with compressed air in a modified commercial batch reactor. Several
parameters affecting biocatalysis at moderate pressures were investigated as follows: pressure, [enzyme], [glucose], pH, temperature,
nature of fluid and the presence of catalase. Glucose 2-oxidase was purified by immobilized metal affinity chromatography
on epoxy-activated Sepharose 6B-IDA-Cu(II) column at pH 6.0. The rate of bioconversion of d-glucose increased with the pressure since an increase in the pressure with compressed air resulted in higher rates of conversion.
On the other hand, the presence of catalase increased the rate of reaction which strongly suggests that H2O2 acted as inhibitor for this reaction. The rate of bioconversion of d-glucose by glucose 2-oxidase in the presence of either nitrogen or supercritical CO2 at 110 bar was very low compared with the use of compressed air at the same pressure. The optimum temperature (55°C) and
pH (5.0) of d-glucose bioconversion as well as kinetic parameters for this enzyme were determined under moderate pressure. The activation
energy (E
a) was 32.08 kJ mol−1 and kinetic parameters (V
max, K
m, K
cat and K
cat/K
m) for this bioconversion were 8.8 U mg−1 protein, 2.95 mM, 30.81 s−1 and 10,444.06 s−1 M−1, respectively. The biomass of C. versicolor as well as the cell-free extract containing glucose 2-oxidase activity were also useful for bioconversion of d-glucose at moderate pressures. The enzyme was apparently stable at moderate pressures since such pressures did not affect
significantly the enzyme activity. 相似文献
927.
Maria Shafique Shahid Hameed Muhammad Moazzam Naseer Najim Aboud Al-Masoudi 《Molecular diversity》2018,22(4):957-968
A series of new chiral 1,3,4-thiadiazole-based bis-sulfonamides 4a–4w and tri-sulfonamide analogue 5 was synthesized and evaluated as anti-HIV agents. The reaction of chiral amino acids 1 with sulfonyl chlorides 2, followed by subsequent reaction of resultant N-protected amino acids 2a–2f with thiosemicarbazide in the presence of excess phosphorous oxychloride afforded N-(1-(5-amino-1,3,4-thiadiazol-2-yl)alkyl)-4-arylsulfonamides 3a–3f. Treatment of 2a–2f with substituted sulfonyl chlorides in portions furnished the target bis-sulfonamide analogues 4a–4w in good yields, together with the unexpected 5. The new compounds were assayed against HIV-1 and HIV-2 in MT-4 cells. Compounds 4s were the most active in inhibiting HIV-1 with IC50?=?9.5 μM (SI?=?6.6), suggesting to be a new lead in the development of an antiviral agent. Interestingly, compound 5 exhibited significant cytotoxicity of >?4.09 μM and could be a promising antiproliferative agent. 相似文献
928.
K. Shahid S. Shahzadi S. Ali M. H. Bhatti K. M. Khan 《Journal of the Iranian Chemical Society》2005,2(2):140-148
4-(2,5-Dioxo-2,5-dihydro-1H-pyrrol-1-yl)benzoic acid and its complexes with methyl-, n-butyl-, phenyl-, benzyl- and octyl-tin have been synthesized and characterized by elemental analysis and spectral studies. The geometry around the tin atom has been deduced from both solid and solution studies. These complexes were also tested against different bacteria and fungi to determine their toxicity. LD50 data was also calculated using the Brine Shrimp method. 相似文献
929.
El Sayed Yousef Amin El-Adawy E.R. Shaaban 《Journal of Physics and Chemistry of Solids》2006,67(8):1649-1655
The optical and acoustic properties of tellurite glasses in the system TeO2/ZrO2/WO3 have been investigated. The refractive index at different wavelengths and the optical spectra of the glasses have been measured. From the refractive index and absorption edge studies for prepared glasses, the optical parameter viz; optical band gap (Eopt), Urbach energy, (ΔE), dispersion energy, Ed, and the average oscillator energy, E0, have been calculated. Sound velocities were measured by pulse echo technique. From these velocities and densities values, various elastic moduli were calculated. The variations in the refractive index, optical energy gap and elastic moduli with WO3 content have been discussed in terms of the glass structure. Quantitatively, we used the bond compression model for analyzing the room temperature elastic moduli data. By calculating the number of bonds per unit volume, the average stretching force constant, and the average ring size we can extract valuable information about the structure of the present glasses. 相似文献
930.
Ali Nouri-Borujerdi Amin R. Noghrehabadi D. Andrew S. Rees 《Transport in Porous Media》2007,69(2):281-288
We examine the effect of local thermal non-equilibrium on the steady state heat conduction in a porous layer in the presence
of internal heat generation. A uniform source of heat is present in either the fluid or the solid phase. A two-temperature
model is assumed and analytical solutions are presented for the resulting steady-state temperature profiles in a uniform porous
slab. Attention is then focussed on deriving simple conditions which guarantee local thermal equilibrium. 相似文献