Search

The objective of the current work is to explore the most appropriate temperature processing technologies (TPTs) and make their assessment based on the desired performance characteristics (assessment criteria) in the context of Indian cold chain (CC) industries. The assessment criteria and explored TPTs have been framed into a model for their theoretical and empirical assessment. The developed model has been analysed using an integrated approach based on Best Worst Method (BWM) and Evaluation Based on the Distance from Average Solution (EDAS) methods. The key findings of the work show that the criteria 'capability to achieve desired temperature' and 'Compatibility with environmental standards' play a crucial role in selecting a TPT for CC applications. Meanwhile, the refrigeration technologies such as 'solar energy-driven tri-generation refrigeration system' and 'passive cold devices as refrigeration technologies' can be adopted to achieve the optimum performance level of CC. To check the robustness of the results, sensitivity analysis has been performed. In addition, the study offers sound theoretical and managerial implications enriching the literature content into the subject domain and suggesting the most suitable TPT for temperature maintenance in CC, which might help the management to make decisions towards organisational growth. [ABSTRACT FROM AUTHOR]

Lanthanide doped fluoride nanoscintillators have received tremendous attention due to their high photochemical stability and tunable X-ray excited optical luminescence compared to traditional inorganic scintillators. Advancement in this field requires design strategies for the development of nanoscintillators that offer tailorable excitation dynamics through nanostructuring, thus enabling high luminescence in a suitable host. However, selection of an appropriate host matrix with low phonon energy and a nanoarchitecture that mitigates surface quenching due to the large surface-to-volume ratio of nanoparticles is still a challenge. Herein, we introduce NaBiF4:Gd,Tb (NBF) nanoparticles as highly efficient nanoscintillators with reduced afterglow to minimize interference in radioimaging, which utilizes the high X-ray attenuation coefficient of bismuth (5.74 cm2 g−1 at about 100 keV). The host NaBiF4 has a high refractive index and low phonon energy, which reduces the multiphonon non-radiative relaxation rates and enhances the radiative emission probability, thus yielding a long-life time for luminescence. Furthermore, by varying the composition of the nanoparticles and the relative concentrations of Gd and Tb, luminescence at multiple wavelengths in changing relative intensities can be achieved to enable multiplexed imaging. We show that NaBiF4:Gd/Tb can be easily synthesized using the co-precipitation method at room temperature within 1 min. Furthermore, we succeeded in fabricating organic–inorganic nanocomposite self-standing films of NaBiF4:Gd,Tb in high loading, uniformly dispersed in poly(methyl methacrylate) (PMMA) polymer. Their application in radiography is demonstrated by recording X-ray images using a commercially available charge-coupled device camera. We attained a resolution comparable to the non-flexible commercial CsI (TI) scintillator and significantly superior to the commercial Gd2O2S:Tb, GOS:Tb scintillators commonly used for screens. [ABSTRACT FROM AUTHOR]

Winds of globalisation and the growing population have prompted food industries to look for effective and efficient production systems. For the same, various technological upgrades need to be ramped up, having the potential to upscale the procedurals involving the processing, preservation, and quality of food products. Thermal processing is one among the highly opted procedural in the food industry and various field advancements allied with it need to be analysed for exploration of the avenues of intelligent manufacturing. Presented work glimpses the various novel thermal technologies clustered from the insights of research literature, to be enacted in the nowadays food processing arena. Various perspectives allied with its adoption are suited to develop a relational hierarchical framework, which is further contemplated by the fundamentals of probability-based hesitant fuzzy numbers. Outcomes secure the primacies allied with the different thermal technologies under consideration, accomplishing towards its adoption. Evaluated values are further checked for the dimension of robustness and reliability by sensitivity analysis, strengthening its implication perspectives. [ABSTRACT FROM AUTHOR]

The tribological simulation can be seen as a new study problem developed through modern information technology and computer simulation technology in combination with a variety of mathematical approaches in the field of tribology. There is a need to seek new conducts and means of in-depth study of the wear quantitative law, or else, it will become difficult for a fundamental breakthrough in the prevention and control of wear to be achieved. The tribological simulation research of the typical Pin-on-Disc sliding wear test system has been carried out by the adoption of computer technology and mathematical analysis methods to provide a new wear-analysis method for the simulation of the basic tribological contact problems. In the present research conduct, an attempt has been made to establish the wear simulation model considering multiple parameters based on experimental and theoretical facts. The parameters of the computational model have been determined through the experimental test data. The simulation model has been observed to reflect the basic relationship between input and output of the pin on the dry disc sliding wear test. Experiments performed have confirmed that, under the conditions analysed, the load effect on the wear rate is more critical than the other conditions. The wear rate varies linearly with the considered load conditions. The simulations have been conducted at the different angular velocities of 50, 60 and 70 rpm. These simulations have also revealed the effect of pin diameter on the depth of wear, and the deep insight into the increase of same with an increase in surface area. [ABSTRACT FROM AUTHOR]

Recently, defect luminescence-based ultralong persistent luminescent (PersL) materials have been increasingly appreciated for advanced applications. However, an in-depth understanding of trap manipulation is a big challenge in controlling trap distribution. In this work, we provide a complete understanding of defect-induced photoluminescence (PL) in Zn2GeO4 and the significant role of different defects and defect complexes. Excitation-dependent tunable emissions from blue to green regions indicated different mechanisms for filling traps for different excitation energies. Time-resolved emission spectroscopy (TRES) revealed time-dependent trap distribution, shifting the PL band from blue to green. The existence of different electron–hole recombination pathways in different time windows shed light on the complex PL of Zn2GeO4. Systematic temperature-dependent PL studies imply different trapping and de-trapping processes. We demonstrate the activation energies for different trapping mechanisms and the role of negative thermal expansion (NTE) of Zn2GeO4 in achieving the negative thermal quenching (NTQ) of PL. Further, the aliovalent doping of Pr3+ was used for trap manipulation and introducing additional intermediate defect states. Density functional theory calculations as well as thermoluminescence and electron paramagnetic resonance studies revealed a reduction in defect formation energies for selective defects, four-fold increase in trap density, and trap re-shuffling to optimum trap depths (0.73 eV) on the doping of Pr3+. The rich trap distribution resulted in a two-fold increase in the quantum yield of green emissions (∼19%) due to Zn interstitial defects. Improved afterglow on UV charging and an increase in the afterglow time from a few minutes in undoped Zn2GeO4 to an intense X-ray activated afterglow for 18 hours was observed in the Pr3+ doped Zn2GeO4 phosphor. Analysis of afterglow decay kinetics revealed the prominent trap-to-trap tunnelling mechanisms for long lifetimes. Impedance studies revealed the widening of electron channels and reduced resistance to electron movement with the incorporation of Pr3+ ions that enhanced PersL. LED fabrication was carried out to demonstrate the potential of the Zn2GeO4 phosphor for solid-state lighting. We believe that such kinetic and thermodynamic interpretation of defect chemistry will be helpful in tailoring the optoelectronic properties of native defect phosphors. [ABSTRACT FROM AUTHOR]

In this paper, the details of the development and performance characterisation of a compact, low-power gamma spectrometer for environmental gamma radiation monitoring networks are presented. To reduce the power consumption and the size of the spectrometer, a gamma detector comprising a silicon photomultiplier coupled to a Gd3Ga3Al2O12:Ce,B (GGAG:Ce,B) scintillator has been used for gamma spectrometry. Initially, a Monte Carlo simulation study was carried out to verify the suitability of the 5 mm × 5 mm × 5 mm GGAG:Ce,B crystal for spectrometry of gamma sources in the energy range 60–1332 keV. For minimising the power consumption, the signal processing electronics has been custom designed. This electronics was realised using standard off-the-shelf components to reduce the cost. The developed spectrometer is of size 16 cm × 10 cm × 6 cm, weighs 600 g and consumes 600 mW power. The spectrometer is developed such that it could be directly interfaced with GSM/Xbee for wireless communication with the radiation monitoring networks. The lower-level discriminator threshold of the system is 40 keV and the total electronic noise is <20 keV. The experimentally measured sensitivity of the spectrometer for 137Cs (662 keV) is 2.4 cps/μGy/h at 3.5 V overvoltage. The spectrometer offers excellent linearity over the measured energy range of 60–1332 keV and an energy resolution of ~10% for 662 keV gamma-ray at room temperature. [ABSTRACT FROM AUTHOR]

Macrocycles are prominent among drugs for treatment of infectious disease, with many originating from natural products. Herein we report on the discovery of a series of macrocycles structurally related to the natural product hymenocardine. Members of this series were found to inhibit the growth of Plasmodium falciparum , the parasite responsible for most malaria cases, and of four kinetoplastid parasites. Notably, macrocycles more potent than miltefosine, the only oral drug used for the treatment of the neglected tropical disease visceral leishmaniasis, were identified in a phenotypic screen of Leishmania infantum . In vitro profiling highlighted that potent inhibitors had satisfactory cell permeability with a low efflux ratio, indicating their potential for oral administration, but low solubility and metabolic stability. Analysis of predicted crystal structures suggests that optimization should focus on the reduction of π-π crystal packing interactions to reduce the strong crystalline interactions and improve the solubility of the most potent lead.

The energy response of gross gamma dose rate monitors needs to be flat in order to prevent overestimation of dose at low gamma energies. In this paper, a discriminator threshold modulation based electronic energy compensation algorithm has been proposed for SiPM-scintillator based gamma detectors. Theoretical simulation studies were carried out in order to optimize the parameters of the periodic ramp voltage used for modulation of the discriminator threshold of a SiPM-GGAG:Ce,B based gamma dose rate monitor. A customized threshold modulation circuit and signal processing electronics were developed for this gamma detector. For experimentally optimizing the parameters, the energy response studies of the detector, with and without the discriminator threshold modulation, were carried out. With the optimized parameters for a periodic ramp threshold, the count rates for 241Am (60 keV) and 60Co (1173 and 1332 keV) were observed to be within ±30% of the count rate obtained for 137Cs (662 keV). Using the electronic energy compensation techniques presented in this paper, a flat energy response of the SiPM-scintillator gamma detector for the energy range of 60 keV to 1.5 MeV could be achieved., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)