Pyrazoles are highly versatile and find applications in various industries including chemicals, pharmaceuticals, polymers, medications, and agriculture. Pyrazoles and their analogues exhibit a range of biological activities, including anti-inflammatory, anti-tuberculosis, antibacterial, antifungal, anti-cancer, and anti-diabetic effects. In this context, this investigation focuses on the synthesis of pyrazoles containing heterocyclic components using Amberlite resin in reactions with ultrasonic irradiation. Synthesized pyrazoles containing heterocyclic components are intermediates of the apixaban API. Some pyrazole derivatives are key impurities of the apixaban API, which is synthesized by a multistep chemical conversion and has been reported previously. The use of the heterogeneous Amberlyst resin, which acts as a reusable catalyst and is gentle on reactions, allows for a more sustainable solution that reduces costs, accelerates reactions, and shortens reaction times. The procedures for using Amberlyst resin under ultrasonic irradiation to synthesize pyrazole derivatives are cost-effective, energy-efficient, and environmentally friendly for chemical synthesis and material preparation. They also simplify workups and produce quality and yields comparable to or better than existing methods.

• Book : 14(1)
• Pub. Date : 2025
• Page : pp.139-148
• Keyword :

Abstract

A transient simulation of shutdown cooling for a gas turbine test rig configuration under ventilated natural convection has been successfully demonstrated using a coupled aerothermal approach. Large eddy simulation (LES) and finite element analysis (FEA) were employed for fluid domain computational fluid dynamics (CFD) and solid component thermal conduction simulation, respectively. Coupling between LES and FEA was achieved through a plugin communicator. The buoyancy-induced chimney effect under the axially ventilated natural convection is correctly reproduced. The hotter turbulent flow in the upper part of the annular path and the colder laminar-type air movement in the lower part of the annulus are appropriately captured. The heat transfer features in the annular passage are also faithfully replicated, with heat flux of the inner cylinder reaching its maximum and minimum at the bottom dead center (BDC) and the top dead center (TDC), respectively. Agreement with experimental measurements is good in terms of both temperature and heat flux, and the result of the transient simulation for the shutdown cooling is encouraging too. In addition, radiation is simulated in the FEA model based on the usual gray body assumptions and Lambert's law for the coupled computation. It has been shown that at the high power (HP) condition, the radiation for the inner cylinder is approximately 11% of its convective heat flux counterpart. The importance of radiation is thus clearly revealed even for the present rig test case with a scaled-down temperature setup.

• Book : 147(3)
• Pub. Date : 2025
• Page : pp.031011
• Keyword :

Abstract

We derive and validate a generalization of the two-point visual control model, an accepted cognitive science model for human steering behavior. The generalized model is needed as current steering models are either insufficiently accurate or too complex for online state estimation. We demonstrate that the generalized model replicates specific human steering behavior with high precision (85% reduction in modeling error) and integrate this model into a human-as-advisor framework where human steering inputs are used for state estimation. As a benchmark study, we use this framework to decipher ambiguous lane markings represented by biased lateral position measurements. We demonstrate that, with the generalized model, the state estimator can accurately estimate the true vehicle state, providing lateral state estimates with under 0.15 m error across participants. However, without the generalized model, the estimator cannot accurately estimate the vehicle’s lateral state.

• Book : 5(1)
• Pub. Date : 2025
• Page : pp.011004
• Keyword :

Abstract

Gamma-ray imaging is a tool that has grown in importance in the applications of non-destructive assay (NDA) for radioactive survey and analysis of nuclear facilities. Imaging techniques have shown great promise in providing valuable information involving radioactive waste management and contamination prevention. For the application studied in this work, 65Zn has been identified as a radioactive contaminant during tritium extraction. Due to the volatile nature of 65Zn under the pressure and temperature changes during extraction operations, 65Zn can easily travel through components of the extraction system as vapor, making it difficult to trap. Previous research involving the development of a filtration system showed that the 65Zn can be trapped, mitigating product contamination. However, during the extraction process, direct analysis of the equipment to confirm that zinc contamination is trapped in the filter and has not spread to other components is impractical. In this situation, the need to assay the location of the contamination with little-to-no interference with operations is vital. In this work, we demonstrate the use of a commercialized 3D position-sensitive CdZnTe (CZT) gamma-ray imaging spectrometer to provide analysis of the 65Zn contamination. Onsite measurements during an extraction process are studied to assess the location and migration of the 65Zn. The results obtained from real-time glovebox monitoring demonstrate the feasibility of gamma-ray imaging for localizing the contamination and providing a preliminary qualitative assessment that is intended to be used in future work quantifying the contamination build-up and activity over time.

• Book : 11(2)
• Pub. Date : 2025
• Page : pp.022001
• Keyword :

• Book : 4(1)
• Pub. Date : 2025
• Page : pp.100141
• Keyword :

Abstract

Al-doped Ga2O3 microbelts with widths ranging from 20 to 154 μm and lengths up to 2 mm were grown using carbothermal reduction. Based on these ultra-wide microbelts, single-microbelt (37 μm wide) and double-microbelts(38 μm/42 μm wide) metal-semiconductor-metal photoconductive ultraviolet (UV) detectors PDs were fabricated and their optoelectronic performances were investigated at Vacuum-UV (VUV) wavelengths of 185 nm. Under irradiation of 185 nm, the Al-doped Ga2O3 PD has a very-high photocurrent (Iph) of 192.07 μA and extremely low dark current (Id) of 156 fA at 10 V, and presents a ultra-high light-to-dark current ratio of 1.23 × 10⁹. The responsivity (R), external quantum efficiency (EQE), and detectivity (D*) of the double-microbelts detector device were 1920 A W⁻¹, 9.36 × 10⁵%, and 8.6 × 10¹⁶ Jones, respectively. Since the bandgap of the Al-doped microbelts becomes wider, and the fabricated detector has weaker sensitivity to radiation in the 254/365 nm wavelengths. Compared with the 254 nm and 365 nm UV cases, the devices under 185 nm VUV show the excellent high selectivity ratios of 1.47 × 10⁶ and 1.7× 10⁷, respectively. This paper should provide a new insight on the VUV photodetectors utilizing Ga2O3 microbelts.

• Book : 36(2)
• Pub. Date : 2025
• Page : pp.025202
• Keyword :

• Book : 20(1)
• Pub. Date : 2025
• Page : pp.560-565
• Keyword :

• Book : 75()
• Pub. Date : 2025
• Page : pp.103176
• Keyword :

• Book : 43(1)
• Pub. Date : 2025
• Page : pp.129-149
• Keyword :

• Book : 178()
• Pub. Date : 2025
• Page : pp.105513
• Keyword :