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1.
LC GC North America ; 39(6):291-292, 2021.
Article in English | ProQuest Central | ID: covidwho-20244058
2.
Aerosol and Air Quality Research ; 23(5), 2023.
Article in English | Web of Science | ID: covidwho-20243921

ABSTRACT

PM2.5 was continuously collected in Ho Chi Minh City (HCMC), Vietnam, during the period from September 2019 to August 2020, which included the period of socioeconomic suppression caused by restrictions imposed in the face of the coronavirus disease of 2019. The concentrations of PM2.5 mass, water-soluble ions (WSIs), organic carbon (OC), elemental carbon (EC), and water-soluble organic carbon (WSOC) were determined to evaluate the seasonal variations in PM2.5, the effect of socioeconomic suppression on PM2.5, and potential PM2.5 sources in HCMC. The PM2.5 mass concentration during the sampling period was 28.44 +/- 11.55 mu g m(-3) (average +/- standard deviation). OC, EC, and total WSIs accounted for 30.7 +/- 6.6%, 9.7 +/- 2.9%, and 24.9 +/- 6.6% of the PM2.5 mass, respectively. WSOC contributed 46.4 +/- 10.1% to OC mass. NO3-, SO42-, and NH4+ were the dominant species in WSIs (72.7 +/- 17.7% of the total WSIs' mass). The concentrations of PM2.5 mass and total WSIs during the rainy season were lower than those during the dry season, whereas the concentrations of carbonaceous species during the rainy season were higher. The concentrations of PM2.5 mass and chemical species during the socioeconomic suppression period significantly decreased by 45%-61% compared to the values before this period. The OC/EC ratio (3.28 +/- 0.61) and char-EC/soot-EC (4.88 +/- 2.72) suggested that biomass burning, coal combustion, vehicle emissions, cooking activities are major PM2.5 sources in HCMC. Furthermore, the results of a concentration-weighted trajectory analysis suggested that the geological sources of PM2.5 were in the local areas of HCMC and the northeast provinces of Vietnam (where coal-fired power plants are located).

3.
IEEE Transactions on Industry Applications ; : 1-7, 2023.
Article in English | Scopus | ID: covidwho-20235410

ABSTRACT

In this paper we report two applications of a subcategory of air cleaning devices based on soft ionization that do not cause molecular fragmentation. A system that includes two unipolar ionizing modules has been used to simultaneously produce positive and negative ions in the air. In one set of experiments a large chamber (28 m3) was used to study the effect of ions on reducing PM1.0 particles produced by a research grade calibrated cigarette. The data presented in this paper were obtained using a carbon-brush-based bipolar ionizer and a MERV 10 filter with electret media in a recirculating HVAC system. Significant improvement in removal rate of fine and ultrafine particles was achieved when using the bipolar ionizer in conjunction with the MERV 10 filter. The second set of experiments were conducted using a 36 m3 chamber, following BSL-3 standards, to study the effect of ions on aerosolized SARS-CoV-2. Results of these investigations reveal the inactivation rate of SARS-CoV-2 are enhanced when ions are introduced in the air;inactivation rates were increased by more than 60%and 90%for ion densities of 10,000/cc and 18,000/cc. IEEE

4.
LC GC North America ; 40(3):125-127, 2022.
Article in English | ProQuest Central | ID: covidwho-20232686

ABSTRACT

In 2002, the first fully humanized mAb was approved by the U.S. Food and Drug Administration (FDA) (3). [...]the biopharmaceutical industry is still in its infancy and new, more complex products are in development and will ikely dominant the market in the future. [...]the most common forms of LC-MS have limitations when characterizing large macromolecules (4). [...]in this column, we discuss the potential for charge detection MS (CDMS) as an analytical tool for characterizing large, complex, and heterogenous biopharmaceuticals. [...]in October 2021 at the American Association for Mass Spectrometry (ASMS) annua meeting in Philadelphia, TrueMass presented the first commercial CDMS (6,7). The cylinder is often inside an electrostatic linear ion trap (ELIT) instrument, where ions oscillate back and forth. [...]the oscillation frequency gives the m/z and the charge is determined by the magnitude.

5.
LC GC North America ; 38(9):532, 2020.
Article in English | ProQuest Central | ID: covidwho-20231684
6.
Front Chem Sci Eng ; : 1-11, 2023 May 18.
Article in English | MEDLINE | ID: covidwho-20242761

ABSTRACT

The current SARS-CoV-2 pandemic has resulted in the widespread use of personal protective equipment, particularly face masks. However, the use of commercial disposable face masks puts great pressure on the environment. In this study, nano-copper ions assembled cotton fabric used in face masks to impart antibacterial activity has been discussed. To produce the nanocomposite, the cotton fabric was modified by sodium chloroacetate after its mercerization, and assembled with bactericidal nano-copper ions (about 10.61 mg·g-1) through electrostatic adsorption. It demonstrated excellent antibacterial activity against Staphylococcus aureus and Escherichia coli because the gaps between fibers in the cotton fabric allow the nano-copper ions to be fully released. Moreover, the antibacterial efficiency was maintained even after 50 washing cycles. Furthermore, the face mask constructed with this novel nanocomposite upper layer exhibited a high particle filtration efficiency (96.08% ± 0.91%) without compromising the air permeability (28.9 min·L-1). This green, economical, facile, and scalable process of depositing nano-copper ions onto modified cotton fibric has great potential to reduce disease transmission, resource consumption, and environmental impact of waste, while also expanding the range of protective fabrics.

7.
Huan Jing Ke Xue ; 44(5): 2430-2440, 2023 May 08.
Article in Chinese | MEDLINE | ID: covidwho-20237414

ABSTRACT

To investigate the change characteristics of secondary inorganic ions in PM2.5 at different pollution stages before and after COVID-19, the online monitoring of winter meteorological and atmospheric pollutant concentrations in Zhengzhou from December 15, 2019 to February 15, 2020 was conducted using a high-resolution (1 h) online instrument. This study analyzed the causes of the haze process of COVID-19, the diurnal variation characteristics of air pollutants, and the distribution characteristics of air pollutants at different stages of haze.The results showed that Zhengzhou was mainly controlled by the high-pressure ridge during the haze process, and the weather situation was stable, which was conducive to the accumulation of air pollutants. SNA was the main component of water-soluble ions, accounting for more than 90%. Home isolation measures during COVID-19 had different impacts on the distribution characteristics of air pollutants in different haze stages. After COVID-19, the concentration of PM2.5 in the clean, occurrence, and dissipation stages increased compared with that before COVID-19 but significantly decreased in the development stage. The home isolation policy significantly reduced the high value of PM2.5. The concentrations of NO2, SO2, NH3, and CO were the highest in the haze development stage, showing a trend of first increasing and then decreasing. The concentration of O3 was lowest in the pre-COVID-19 development stage but highest in the post-COVID-19 development stage. The linear correlation between[NH4+]/[SO42-] and[NO3-]/[SO42-] at different time periods before and after COVID-19 was strong, indicating that the home isolation policy of COVID-19 did not change the generation mode of NO3-, and the corresponding reaction was always the main generation mode of NO3-. The correlation between[excess-NH4+] and[NO3-] was high in different periods before COVID-19, and NO3- generation was related to the increase in NH3 or NH4+ in the process of PM2.5 pollution in Zhengzhou.


Subject(s)
Air Pollutants , Air Pollution , COVID-19 , Humans , Particulate Matter/analysis , Environmental Monitoring/methods , COVID-19/epidemiology , Respiratory Aerosols and Droplets , Air Pollutants/analysis , Air Pollution/analysis , Ions/analysis , Seasons , China/epidemiology
8.
Journal of Aerosol Science ; : 106199, 2023.
Article in English | ScienceDirect | ID: covidwho-2316178

ABSTRACT

Small air ions have the ability to charge airborne particles, thereby increasing their accumulation on surfaces. Indoor air purification by applying ionization uses electrostatic particle deposition. Respiratory pathogens, including viruses and respiratory droplets carrying viruses or other pathogens, represent bioaerosols, whose particle size distributions contain increasingly larger proportion of fine and ultrafine particles, as the evaporation process proceeds. We have generated two model aerosols: the nebulized NaCl solution, resembling human saliva, and the cigarette smoke, having relatively low water content. We have conducted real life experiments of such surrogate aerosol particle deposition without ionization, using bipolar ionization, as well as using unipolar negative air ions. Particle number concentrations have been measured in the 10 nm–10 μm particle size range. The calculated deposition rates and aerosol particle half-life times were correlated with bioaerosol pathogens based on the core pathogen sizes. Bipolar ionizers emitting equal concentrations of positive and negative ions had low impact to the particle concentration decrease. Intense negative air ionization resulted in pronounced deposition rate increases, particularly in the particle size range of viruses including the SARS-CoV-2. The impact of negative air ionization was most pronounced in the same size range where the deposition rates without ionization were the lowest. Therefore, the results are very promising from the standpoint of air purification and bioaerosol pathogen removal, bearing in mind that the effect of ions will be most pronounced if the unipolar ion rich air stream is directed towards the breathing zone.

9.
Environmental Engineering Research ; 28(3), 2023.
Article in English | Web of Science | ID: covidwho-2307329

ABSTRACT

Rivers are our country's lifeline;however, we have done enough destruction to them which leads to deterioration in water quality. Fortunately, COVID-19 lockdown has brought new life to nature. This encouraged us to outline present review article which discusses pilot impacts of lockdown on six Indian rivers. Few rivers including Ganga showed major improvement at few sites in the assessed parameters such as pH, BOD, DO, FC, etc. The Ganga water at Haridwar and Rishikesh was investigated `fit for drinking' (Class A) while at Kanpur was found fit for `outdoor bathing' (Class B). These improvements can be attributed to strict restriction on human activities during lockdown as there were no or minimum industrial discharge, tourism activities, mass bathing and commercial events near rivers. However, after upliftment of lockdown, these activities will return to their previous state and most likely pollutants will eventually reappear in the water bodies. So, in this review we have reviewed government's existing water pollution control schemes, analysed their limitations and recommended several scopes for improvement. Further research directions in this area have also been highlighted. We believe that plans and actions described in the article, if implemented, will lead to fruitful outcomes in managing water resources.

10.
Chembiochem ; 24(10): e202300034, 2023 05 16.
Article in English | MEDLINE | ID: covidwho-2308421

ABSTRACT

CRISPR-LbuCas13a has emerged as a revolutionary tool for in vitro diagnosis. Similar to other Cas effectors, LbuCas13a requires Mg2+ to maintain its nuclease activity. However, the effect of other divalent metal ions on its trans-cleavage activity remains less explored. Herein, we addressed this issue by combining experimental and molecular dynamics simulation analysis. In vitro studies showed that both Mn2+ and Ca2+ could replace Mg2+ as cofactors of LbuCas13a. In contrast, Ni2+ , Zn2+ , Cu2+ , or Fe2+ inhibits the cis- and trans-cleavage activity, while Pb2+ does not affect it. Importantly, molecular dynamics simulations confirmed that calcium, magnesium, and manganese hydrated ions have a strong affinity to nucleotide bases, thus stabilizing the conformation of crRNA repeat region and enhancing the trans-cleavage activity. Finally, we showed that combination of Mg2+ and Mn2+ can further enhance the trans-cleavage activity to allow amplified RNA detection, revealing its potential advantage for in vitro diagnosis.


Subject(s)
Manganese , RNA , Calcium/metabolism , Molecular Conformation , Magnesium , CRISPR-Cas Systems
11.
Carbon ; 209, 2023.
Article in English | Scopus | ID: covidwho-2306451

ABSTRACT

The global pandemic of COVID-19 poses significant challenge to the recycling of disposable polypropylene (PP)-based waste masks. Herein, a simple but effective sulfonation route has been proposed to transform PP-based waste masks into value-added hard carbon (CM) anode materials for advanced sodium-ion batteries. The sulfonation treatment improves the thermal stability of the PP molecule, preventing their complete decomposition and the release of massive gas molecules during the carbonization process. Meanwhile, the oxygen functional groups introduced during sulfonation effectively facilitates the cross-linking between the PP chains, hindering the rearrangement of carbon microcrystalline structures and enhancing its structural disorder. As a result, the prepared hard carbon anode (CM-180) with a high disorder degree and minimal surface defects realizes a high sodium storage capacity of 327.4 mAh g−1 with excellent cycle and rate capability. In addition, when coupled with O3–NaNi1/3Fe1/3Mn1/3O2 cathode, the fabricated sodium-ion full cell delivers a high energy density of 238 Wh kg−1 and achieves an outstanding rate capability with a retained capacity of 75 mAh g−1 even at an ultrahigh current rate of 50 C. This work offers a novel insight into transforming the waste masks to value-added hard carbons with promising prospects for sodium-ion batteries. © 2023

12.
Molecular Crystals and Liquid Crystals ; 2023.
Article in English | Scopus | ID: covidwho-2302365

ABSTRACT

Detailed structural and noncovalent interactions in two thiazole derivatives (N-(4-Bromophenyl)-2-(methylthio)thiazole-5-carboxamide and Ethyl-5-((4-bromophenyl)carbamoyl)thiazole-4-carboxylate) are investigated by single crystal X-ray diffraction study and computational approaches. The structure investigation revealed that various interactions like C-H…O, N-H…O, and N-H…N hydrogen bonds and Br…Br interactions are involved in constructing ring motifs to stabilize the crystal packing. Hirshfeld surface analysis and fingerprint plots were carried out to study the differences and similarities in the relative contribution of noncovalent interactions in both the molecules. The FMOs and other global reactive parameters are analyzed for thiazole derivatives. The strength and nature of weak interactions present in the molecule were characterized by RDG-based NCI and QTAIM analyses. Natural bond orbital (NBO) analysis unravels the importance of non-covalent and hyperconjugative interactions for the stability of the molecules in their solid state. Further, molecular docking of N-(4-Bromophenyl)-2-(methylthio)thiazole-5-carboxamide and Ethyl-5-((4-bromophenyl)carbamoyl)thiazole-4-carboxylate with SARS-Covid-19 have been carried out. © 2023 Taylor & Francis Group, LLC.

13.
Build Simul ; : 1-16, 2022 Dec 02.
Article in English | MEDLINE | ID: covidwho-2302451

ABSTRACT

Infectious diseases (e.g., coronavirus disease 2019) dramatically impact human life, economy and social development. Exploring the low-cost and energy-saving approaches is essential in removing infectious virus particles from indoors, such as in classrooms. The application of air purification devices, such as negative ion generators (ionizers), gains popularity because of the favorable removal capacity for particles and the low operation cost. However, small and portable ionizers have potential disadvantages in the removal efficiency owing to the limited horizontal diffusion of negative ions. This study aims to investigate the layout strategy (number and location) of ionizers based on the energy-efficient natural ventilation in the classroom to improve removal efficiency (negative ions to particles) and decrease infection risk. Three infected students were considered in the classroom. The simulations of negative ion and particle concentrations were performed and validated by the experiment. Results showed that as the number of ionizers was 4 and 5, the removal performance was largely improved by combining ionizer with natural ventilation. Compared with the scenario without an ionizer, the scenario with 5 ionizers largely increased the average removal efficiency from around 20% to 85% and decreased the average infection risk by 23%. The setup with 5 ionizers placed upstream of the classroom was determined as the optimal layout strategy, particularly when the location and number of the infected students were unknown. This work can provide a guideline for applying ionizers to public buildings when natural ventilation is used. Electronic Supplementary Material ESM: the Appendix is available in the online version of this article at 10.1007/s12273-022-0959-z.

14.
FarmaJournal ; 7(1):7-17, 2022.
Article in Spanish | ProQuest Central | ID: covidwho-2271244

ABSTRACT

La microbiota varía con el tiempo, por ello durante el curso académico 2019-20, coincidiendo con la pandemia SARS-COV-2, se evaluó la evolución de la misma en un aula de la Facultad de Farmacia de la Universidad de Salamanca con la espectrometría de masas Matrix-assisted laser desorption ionization time-of-flight. Además, se comparó con otros estudios, así como con las directrices de la Comisión de la Comunidad Europea de calidad del aire de interiores. Tras el estudio se concluyó que dicha aula presentaba un grado de contaminación muy bajo, y que la mayoría de la microbiota era saprofítica. Asimismo, de forma general se puede concluir que de forma cuantitativa los hongos y de forma cuali-cuantitativa las bacterias no presentaban un riesgo para la salud. Por otro lado, entre las variables más importantes encontramos la afluencia de personas, la frecuencia de limpieza y la ventilación. Finalmente, este estudio recoge la poca normativa que existe sobre la calidad del aire en interiores no industriales y no hospitalarios.Alternate abstract:Microbiota varies over time, therefore during 2019-20 academic year, coinciding with the SARS-COV-2 pandemic, the evolution of it was evaluated in a classroom of the Faculty of Pharmacy of the University of Salamanca with mass spectrometry Matrix-assisted laser desorption ionization time-of-flight. In addition, this study was compared with others, as well as with guidelines of the European Community Commission on indoor air quality. After the study, it was concluded that said classroom had very low contamination degree and that most of microbiota was saprophytic. Furthermore, it can be concluded that quantitatively fungi and quantitatively and qualitatively the bacteria did not present a health risk. On the other hand, the most important variables that were found were the influx of people, the frequency of cleaning and ventilation. Finally, this study shows off the lack of regulation that exists on air quality in non-industrial and non-hospital interiors.

15.
Horticulturae ; 9(2):226, 2023.
Article in English | ProQuest Central | ID: covidwho-2268858

ABSTRACT

The nutritional quality and biomass of various sprouts can be enhanced by Zn and red-blue light, especially the Brassica sprouts. However, the combined effects of this two on sprouts are rarely reported. In this study, different Zn concentrations (0, 1.74, 3.48, 10.43 and 17.39 mM) were combined with two ratios of red-blue light-emitting diodes (LEDs) (R: B = 1:2, 1R2B;R: B = 2:1, 2R1B, at 70 μmol m−2 s−1 PPFD, 14 h/10 h, light/dark) to investigate their mutual effects on the growth, mineral elements, and nutritional quality in flowering Chinese cabbage sprouts (FCCS). Fresh weight, dry weight, contents of organic Zn, soluble sugar, vitamin C, total flavonoids, total polyphenol, FRAP (ferric ion-reducing antioxidant power) and DPPH (radical inhibition percentage of 1,1-diphenyl-2-picrylhydrazyl) were significantly increased by Zn supplement (10.43 and 17.39 mM) and 2R1B, while hypocotyl length and moisture content were decreased remarkably by Zn supplement. Total glucosinolates contents in the sprouts increased dramatically under 2R1B compared with 1R2B, while photosynthetic pigments contents decreased. Heat map and principal component analysis showed that 2R1B + 17.39 mM Zn was the optimal treatment for the accumulation of biomass and health-promoting compound in FCCS, suggesting that a suitable combination of light quality and Zn supplement might be beneficial to zinc-biofortified FCCS production.

16.
Antimicrobial Stewardship and Healthcare Epidemiology ; 3(S1):s2-s3, 2023.
Article in English | ProQuest Central | ID: covidwho-2265169

ABSTRACT

Objectives: The widespread distribution of SARS-CoV-2 and its high contagiousness pose a challenge for researchers seeking to develop a rapid and cost-effective screening method to identify carriers of this virus. RT-PCR is considered the gold standard for detecting viral RNA in nasopharyngeal swabs, but it is time-consuming and requires constant changes in the primer composition due to the mutation of SARS-CoV-2 strains. We propose a method for the detection of SARS-CoV-2 in nasopharyngeal swabs using MALDI-TOF MS and machine learning. Methods: Nasopharyngeal swabs from patients with PCR-confirmed COVID-19 and control participants were tested (130 and 80 swabs, respectively) with MALDI-TOF MS MicroFlex LT using the HCCA matrix. MALDI spectra were preprocessed in R version 4.1.2 software with the MALDIquant R package using the workflow: sqrt transformation, wavelet smoothing, SNIP-based base removal, and PQN intensity calibration. Peaks were detected with MAD algorithms with following Peak alignment on the following parameters: minFreq 70% and tolerance 0.005. Machine learning was performed with the rtemis r package on GLM, random forest, and XGBoost models. Results: These models were characterized by specificity, sensitivity, and F1 score. GLM models (specificity 1 and sensitivity 0.5) showed a low F1 score of 0.71. However, the random forest and XGBoost models demonstrated sensitivity, specificity, and F1 score equaling 1. Conclusions: We propose a screening method for SARS-CoV-2 detection (sensitivity 1 and specificity 1). This methodology combines the analysis of nasopharyngeal swab samples using MALDI-TOF-MS with machine learning. It is suitable for screening patients with COVID-19 at the first stages of diagnosis. Random forest and XGBoost models demonstrated sensitivity, specificity, and F1 scores equaling 1.

17.
Energy ; 272, 2023.
Article in English | Scopus | ID: covidwho-2261563

ABSTRACT

The Russia-Ukraine conflict and the COVID-19 pandemic have made fossil energy more urgent, and the catalytic pyrolysis of biomass is conducive to energy transformation to achieve global sustainable development. In this paper, the influence mechanisms of different metal ions on biomass pyrolysis under conventional heating and microwave heating conditions were studied. Through thermogravimetric analysis, it was found that the existence of metal ions could change the pyrolysis behaviors of biomass, leading to different degrees of changes in the main pyrolysis temperature and range. Compared with conventional heating conditions, metal ion-loaded biomass samples exhibited higher heating rates under microwave heating conditions due to the possible hotspot phenomenon, resulting in increased gas yields and decreased bio-oil yields. Among them, the trivalent iron ion exhibited excellent catalytic properties for gas generation, with a high gas yield of 57.9% and a bio-oil yield of 12.1%. The components in bio-oil were greatly simplified by microwave irradiation, the number of the bio-oil compounds from the pyrolysis of Fe-loading pine sawdust was reduced to 77, and the GC-MS area of light compounds with carbon number less than 10 was increased to 84.4%. Phenol and furan in bio-oil are also catalytically converted into aromatic hydrocarbons, which are ideal chemical raw materials. © 2023 Elsevier Ltd

18.
Journal of Molecular Structure ; 1282, 2023.
Article in English | Scopus | ID: covidwho-2258419

ABSTRACT

Oxadiazines are heterocyclic compounds containing two nitrogen and one oxygen atom in a six-membered ring. The synthesis and crystal structure of 4-(4-methoxyphenyl)-6-methyl-3-phenyl-4H-1,2,4-oxadiazin-5(6H)-one (MPMP-OXA) was reported. The organic crystal structure of the synthesized compound was fully characterized by various spectroscopic techniques (Fourier Transform Infrared Spectroscopy, NMR and LC/MS-TOF) and single-crystal X-ray diffraction studies. The MPMP-OXA crystal structure crystallizes in the triclinic system and space group P-1 with a = 5.9395(15) Å, b = 11.471(3) Å, c = 11.901(3) Å, α = 70.075(4)°, β = 83.454(4)°, γ = 78.016(4)°, V = 744.9(3) Å3, Z = 2 cell parameters. This work is aimed to study the weak interactions in the crystal packing of a new synthesized oxadiazine derivate. The contributions of the most important intermolecular interactions in the crystal structure were investigated by 3D-Hirshfeld surface (HS) and 2D-fingerprint analysis. The C[sbnd]H···O interactions as the most important contributors to the crystal packing between the oxygen of the oxadiazine ring and the hydrogen atom of phenyl ring appear as bright red spots visible on the HS surface. The hydrogen-bonded interaction of MPMP-OXA has been investigated using noncovalent interactions approach. The molecular docking studies for the synthesized compound were performed to gain insight into the inhibition nature of this molecule against DNA Gyrase B Candida and 3-chymotrypsin-like protease (SARS-CoV main protease) proteins and resulted in good activities for new anti-agents. Lastly, Bioavailability, druggability as well as absorption, distribution, metabolism, excretion, and toxicity parameters (ADMET), and gastrointestinal absorption (BOILED-Egg method) properties of newly synthesized compound using smile codes were performed in detail. © 2023 Elsevier B.V.

19.
2022 International Electron Devices Meeting, IEDM 2022 ; 2022-December:735-738, 2022.
Article in English | Scopus | ID: covidwho-2257742

ABSTRACT

Conventional X-ray imaging architectures feature data redundancy and hardware consumption due to the separated sensory terminal and computing units. In-sensor computing architectures is promising to overcome such drawbacks. However, its realization in X-ray range remains elusive. We propose ion distribution induced reconfigurable mechanism, and demonstrate the first X-ray band in-sensor computing array based on Pb-free perovskite. Redistribution of Br- ion in perovskite induces the switching of PN and NP modes under electrical pooling. X-ray detection sensitivity can be switched between two stable self-power sensing modes with 4373±298 and -7804±429 mu mathrm{CGy}-{ mathrm{a} mathrm{i} mathrm{r}}{}{-1} mathrm{cm}{-2} respectively, which are superior than that of commercial a-Se detectors (20 mu mathrm{C} mathrm{G} mathrm{y}-{ mathrm{a} mathrm{i} mathrm{r}}{}{-1} mathrm{c} mathrm{m}{-2}). Both modes exhibit low detection limit of 48.4 mathrm{n} mathrm{G} mathrm{y}-{ mathrm{a} mathrm{i} mathrm{r}} mathrm{s}{-1}, which is two orders lower than typical medical dose rate of 5.5 mu mathrm{G} mathrm{y}-{ mathrm{a} mathrm{i} mathrm{r}} mathrm{s}{-1}. The perovskite array sensors can integrate with thin film transistors (TFTs) with low-temperature (80oC) process with good uniformity. An in-sensor computing algorithm of attention mechanism is performed on array sensors for chest X-ray images COVID-19 recognition, which enables an accuracy improvement up to 98.2%. Our results can pave the way for future intelligent X-ray imaging. © 2022 IEEE.

20.
Applied Organometallic Chemistry ; 37(3):1-28, 2023.
Article in English | Academic Search Complete | ID: covidwho-2247764

ABSTRACT

The 5‐(4‐aryl azo)‐8‐hydroxyquinolines (L1–L3) and their metal complexes with Ni2+ and Zn2+ have been produced. Various spectroscopic techniques have been employed to analyze the ligand and complexes. The structures of the prepared compounds have been confirmed by Fourier transform infrared (FT‐IR), proton nuclear magnetic resonance (1H NMR), molar conductance, magnetic measurements, thermal gravimetric and differential thermal analyses (TG and DTA), and electronic transition. The FT‐IR spectra showed that the ligands are coordinated to the metal ions in a bidentate manner with donor sites of the azomethine‐N and phenolic‐OH. The FT‐IR and UV–Visible spectra were compared with the calculated results and showed a good agreement. The mass spectra concluded that the ligands' molecular weights and the calculated estimated m/z values match well. The complexes contain coordinated and hydrated water as confirmed by the TG results. The complexes are tetrahedral, trigonal bipyramid, and octahedral geometrical structures and act as non‐electrolytes in dimethylformamide (DMF) solvent. Using density functional theory (DFT) at the B3LYP level of theory and the 6‐311G** basis set for the C, H, N, Cl, and O atoms and the LANL2DZ basis set for the Ni and Zn atoms. Natural bond orbital (NBO) analysis was used to compute and describe the natural charge population and precise electronic configuration. The small energy gap between HOMO and LUMO energies suggests that charge transfer occurs within Ni2+ and Zn2+ complexes. The first‐order hyperpolarizability (β) of the complexes and the anisotropy of polarizability (α) values show promising optical properties. The electronic transitions of the prepared complexes were computed by time‐dependent density functional theory (TD‐DFT/PCM) with the B3LYP method using a 6‐31G** basis set. The ethanol polarizable continuum model (PCM) was used to simulate the solvent effect. Utilizing a computer virtual screening technique through molecular docking, the anticipation of binding of 8‐quinolinolazodye derivatives and their complexes with human CORONA virus protein (PDB ID: 5epw) was done. [ FROM AUTHOR] Copyright of Applied Organometallic Chemistry is the property of John Wiley & Sons, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

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