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1.
RSC Adv ; 14(19): 13374-13383, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38660528

RESUMEN

Carbon-based perovskite solar cells (PSCs) have emerged as a hopeful alternative in the realm of photovoltaics. They are considered promising due to their affordability, remarkable durability in humid environments, and impressive electrical conductivity. One approach to address the cost issue is to use affordable counter electrodes in PSCs that do not require organic hole transport materials (HTMs). This study utilized an innovative and economical method to create NiOx/PANI nanocomposites. Later, these nanoparticles were integrated into a carbon paste to act as an HTM. This incorporation is intended to optimize charge extraction, improve interfacial contact, align energy levels, reduce energy loss, minimize charge recombination, and protect the perovskite (FAPbI3) surface from degradation. The optoelectronic properties of these devices were investigated, and all cells showed improved efficiency compared to control cells. The NiOx/PANI doped carbon (NiOx/PANI+CE) exhibited excellent performance due to strong hole conductivity, well-aligned energy levels, and the formation of stepwise band alignment at the perovskite interface.

2.
Nanoscale Adv ; 6(2): 548-558, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38235071

RESUMEN

Improving the role of electron-transport layers (ETLs) in carbon-based perovskite solar cells (CPSCs) is a promising method to increase their photovoltaic efficiency. Herein, we employed rGO sheets decorated with ZrO2 nanoparticles to increase the electron transport capability of mesoporous TiO2 ETLs. We found that the rGO/ZrO2 dopant enhanced the conductivity of the ETL, reducing the charge-transfer resistance at the ETL/perovskite interface and reducing charge recombination in the corresponding CPSCs. Notably, this dopant did not effectively change the transparency of ETLs, while increasing the light-harvesting ability of their own top perovskite layer by improving the crystallinity of the perovskite layer. The rGO/ZrO2-containing ETLs produced a champion efficiency of 15.21%, while devices with a net ETL recorded a maximum efficiency of 11.88%. In addition, the modified devices showed a higher stability behavior against ambient air than the net devices, which was linked to the passivated grain boundaries of the modified perovskite layers along with the improved hydrophobicity.

3.
RSC Adv ; 14(4): 2429-2438, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38223694

RESUMEN

The current study focuses on boosting the photocatalytic ability of reduced graphene oxide (rGO) by decorating the rGO nano-sheets with nickel oxide (NiOx) and silver (Ag) nanomaterials. The developed ternary nanomaterials were investigated using FTIR, XRD, FESEM, TEM, Raman, and UV-vis to evaluate the photo-degradation process. The rGO/NiOx/Ag ternary system showed promising photocatalytic dye degradation under simulated sunlight irradiance. The addition of NiOx and Ag nanomaterials widened the catalytic activity spectrum from the visible region to the UV-region. Besides, these materials hindered the electron-hole recombination, boosting the catalytic activity. The reusability results also clearly showed that the synthesized ternary nanomaterials have good reproducibility and stability for photocatalytic degradation of industrial wastewater.

4.
RSC Adv ; 13(42): 29163-29173, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37800128

RESUMEN

This study investigated the potential suitability of graphene quantum dots (GQD) and certain edge-functionalized GQDs (GQD-3Xs) as hole transport materials (HTMs) in perovskite solar cells (PSCs). The criteria for appropriate HTMs were evaluated, including solubility, hole mobility, light harvesting efficiency (LHE), exciton binding energy (Eb), hole reorganization energy (λh), hole mobility, and HTM performance. It was found that several of the compounds had higher hole mobility than Spiro-OMeTAD, a commonly used HTM in PSCs. The open circuit voltage and fill factor of the suitable GQD and GQD-3Xs were found to be within appropriate ranges for HTM performance in MAPbI3 PSCs. GQD-COOH and GQD-COOCH3 were identified as the most suitable HTMs due to their high solubility, small λh, and appropriate performance.

5.
Sci Rep ; 13(1): 9076, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37277466

RESUMEN

According to recent reports, planar structure-based organometallic perovskite solar cells (OPSCs) have achieved remarkable power conversion efficiency (PCE), making them very competitive with the more traditional silicon photovoltaics. A complete understanding of OPSCs and their individual parts is still necessary for further enhancement in PCE. In this work, indium sulfide (In2S3)-based planar heterojunction OPSCs were proposed and simulated with the SCAPS (a Solar Cell Capacitance Simulator)-1D programme. Initially, OPSC performance was calibrated with the experimentally fabricated architecture (FTO/In2S3/MAPbI3/Spiro-OMeTAD/Au) to evaluate the optimum parameters of each layer. The numerical calculations showed a significant dependence of PCE on the thickness and defect density of the MAPbI3 absorber material. The results showed that as the perovskite layer thickness increased, the PCE improved gradually but subsequently reached a maximum at thicknesses greater than 500 nm. Moreover, parameters involving the series resistance as well as the shunt resistance were recognized to affect the performance of the OPSC. Most importantly, a champion PCE of over 20% was yielded under the optimistic simulation conditions. Overall, the OPSC performed better between 20 and 30 °C, and its efficiency rapidly decreases above that temperature.

6.
Phys Chem Chem Phys ; 25(24): 16459-16468, 2023 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-37306330

RESUMEN

Enhanced radiative efficiency, long carrier lifetimes, and high carrier mobilities are hallmarks of perovskite solar cells. Considering this, complete cells experience large nonradiative recombination losses that restrict their VOC considerably below the Shockley-Queisser limit. Auger recombination, which involves two free photo-induced carriers and a trapped charge carrier, is one potential mechanism. Herein, the effects of Auger capture coefficients in mixed-cation perovskites are analyzed employing SCAPS-1D computations. It is demonstrated that VOC and FF are severely decreased with an increase in the acceptor concentration and Auger capture coefficients of perovskites, thus reducing the device performance. When the Auger capture coefficient is increased to 10-20 cm6 s-1 under the acceptor concentration of 1016 cm-3, the performance is drastically lowered from 21.5% (without taking Auger recombination into account) to 9.9%. The findings suggest that in order to increase the efficiency of perovskite solar cells and prevent the effects of Auger recombination, the Auger recombination coefficients should be less than 10-24 cm6 s-1.

7.
PLOS Glob Public Health ; 3(6): e0001677, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37315072

RESUMEN

Anemia accounts for 8.8% of total disability burden worldwide. Betel quid use among pregnant women has been found to increase anemia risk. Betel quid is prepared by wrapping the betel (or areca) nut, with spices and other additions, in betel or tobacco leaf and it is chewed or placed in the mouth. We explored the association between betel quid use and anemia among men and non-pregnant women. We collected data from a random sample of women and their husbands in Matlab, Bangladesh. Participants reported their current betel quid use and individual characteristics. We assessed hemoglobin (a biomarker of anemia) with a hemoglobinometer and soluble transferrin receptor (a biomarker of iron deficiency) and C-reactive protein (a biomarker of inflammation) in dried blood spots via enzyme immunoassay. We estimated logistic regression models to evaluate the association between betel quid use and anemia and structural equation models (SEM) to evaluate mediating roles of iron deficiency and elevated inflammation. A total of 1133 participants (390 men and 743 non-pregnant women) were included. After controlling for important confounders, any betel quid use was positively associated with anemia among men (OR: 1.80; 95% CI: 1.12, 2.89). Among women, betel quid use was associated with anemia only among the most frequent users (OR: 1.62; 95% CI: 1.03, 2.53). SEM did not reveal indirect paths through inflammation or iron deficiency. Betel quid use may contribute to the burden of anemia among adults in Bangladesh. Our findings suggest the burden of disease attributed to betel quid use has been underestimated.

8.
J Mol Graph Model ; 122: 108481, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37146386

RESUMEN

In the present work, the structure and electronic properties of Ti-, Cr-, Fe-, Ni-, Zn-, and Cu-inserted in porphyrin-reduced C70 fullerenes (TM-PIC70Fs) and their interactions with the ethenone were studied using DFT, NBO, and TD-DFT at CAM-B3LYP/6-31G(d) level of theory. 2.89-3.83 and 4.02-4.56 eV were obtained for the HOMO-LUMO gap energies and work functions of TM-PIC70Fs, respectively, compared with 3.76 and 4.54 eV for PIC70F. Among considered TM-PIC70Fs, the adsorption of the ethenone on Ti-PIC70F appreciably changed the HOMO-LUMO energy gap and work function. Consequently, Ti-PIC70F may be used as the ethenone's electronic conductivity and work function types sensor. According to calculated UV-visible spectra, the ethenone adsorption may change the color of Fe- and Ti-PIC70Fs. Therefore, they can be used as color-changing sensors of ethenone. In addition, Ti-, Cr-, Fe-, and Zn-PIC70Fs can be employed as suitable adsorbents of ethenone. Among proper sensors and adsorbents of ethenone, Cr-, Fe-, and Zn-PIC70Fs may be recovered and reused.


Asunto(s)
Fulerenos , Metaloporfirinas , Teoría Funcional de la Densidad , Modelos Moleculares , Fulerenos/química , Espectroscopía Infrarroja por Transformada de Fourier , Teoría Cuántica , Espectrometría Raman
9.
RSC Adv ; 13(18): 12554-12571, 2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37101948

RESUMEN

Density Functional Theory (DFT) was employed to investigate the interaction between cyanogen chloride (ClCN) and the surface of a carbon nanocone (CNC). The findings of this research revealed that pristine CNC is not an ideal material to detect ClCN gas due to its minimal alterations in electronic properties. In order to enhance the properties of carbon nanocones, multiple methods were implemented. These included functionalizing the nanocones with pyridinol (Pyr) and pyridinol oxide (PyrO) as well as decorating them with metals such as boron (B), aluminium (Al) and gallium (Ga). Additionally, the nanocones were also doped with the same third-group metal (B, Al and Ga). The simulation results indicated that doping it with aluminium and gallium atoms yielded promising results. After a comprehensive optimization process, two stable configurations were obtained between the ClCN gas and the CNC-Al, and CNC-Ga structures (configurations S21, and S22) with E ads values of -29.11, and -23.70 kcal mol-1 respectively, using M06-2X/6-311G(d) level. The adsorption of ClCN on CNC-Al and CNC-Ga surfaces leads to a marked alteration in the electrical properties of these structures. Calculations reveal that the energy gap between the Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) levels (E g) of these configurations increased in the range of 9.03% and 12.54%, respectively, thereby giving off a chemical signal. An analysis conducted by the NCI confirms that there is a strong interaction between ClCN and Al and Ga atoms in CNC-Al and CNC-Ga structures, which is represented by the red color in the RDG isosurfaces. Additionally, the NBO charge analysis reveals that significant charge transfer is present in S21 and S22 configurations (190 and 191 |me|, respectively). These findings suggest that the adsorption of ClCN on these surfaces impacts the electron-hole interaction, which subsequently alters the electrical properties of the structures. Based on the DFT results, the CNC-Al and CNC-Ga structures, which have been doped with aluminium and gallium atoms, respectively, have the potential to serve as good candidates for detecting ClCN gas. Among these two structures, the CNC-Ga structure emerged as the most desirable one for this purpose.

10.
RSC Adv ; 13(2): 1402-1411, 2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36686937

RESUMEN

Formamidinium lead iodide (FAPbI3) is the most promising perovskite material for producing efficient perovskite solar cells (PSCs). Here, we develop a facile method to obtain an α-phase FAPbI3 layer with passivated grain boundaries and weakened non-radiative recombination. For this aim, during the FAPbI3 fabrication process, cetrimonium bromide + 5% potassium thiocyanate (CTABr + 5% KSCN) vapor post-treatment is introduced to remove non-perovskite phases in the FAPbI3 layer. Incorporation of CTA+ along with SCN- ions induces FAPbI3 crystallization and stitch grain boundaries, resulting in PSCs with lower defect losses. The vapor-assisted deposition increases the carriers' lifetime in the FAPbI3 and facilitates charge transport at the interfacial perovskite/hole transport layer via a band alignment phenomenon. The treated α-FAPbI3 layers bring an excellent PCE of 22.34%, higher than the 19.48% PCE recorded for control PSCs. Besides, the well-oriented FAPbI3 and its higher hydrophobic behavior originating from CTABr materials lead to improved stability in the treated PSCs.

11.
J Pharm Bioallied Sci ; 14(Suppl 1): S1030-S1032, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36110812

RESUMEN

Rehabilitation of distal extension cases is one of the common challenges in dentistry as fabrication of fixed prosthesis is impossible. For the prosthetic rehabilitation of distal extension, implant-supported prosthesis, cast partial denture, and precision attachment prosthesis can be used. Precision attachment helps in the distribution of masticatory forces, minimizes trauma to abutments and soft tissues, improves the esthetics, and retains proprioception and thus better comfort to the patient. This case report presents the fabrication of precision attachment to retain maxillary and mandibular partial dentures.

12.
RSC Adv ; 12(32): 20461-20470, 2022 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-35919164

RESUMEN

With the increase in the importance of using green energy sources to meet the world's energy demands, attempts have been made to push perovskite solar cell technology toward industrialization all around the world. Improving the properties of perovskite materials as the heart of PSCs is one of the methods to fabricate favorable photovoltaic (PV) solar cells based on perovskites. Here, cadmium chloride (CdCl2) was used as an additive source for the perovskite precursor to improve its PV properties. Results indicated CdCl2 improves the perovskite growth and tailors its crystalline properties, suggesting boosted charge transport processes in the bulk and interfaces of the perovskite layer with electron-hole transport layers. Overall, by incorporation of 1.0% into the MAPbI3 layer, a maximum power conversion efficiency of 15.28% was recorded for perovskite-based solar cells, higher than the 12.17% for the control devices. The developed method not only improved the PV performance of devices but also boosted the stability behavior of solar cells due to the passivated domain boundaries and enhanced hydrophobicity in the CdCl2-based devices.

13.
Global Health ; 17(1): 81, 2021 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-34275481

RESUMEN

BACKGROUND: Among Bangladeshi men, international labor migration has increased ten-fold since 1990 and rural to urban labor migration rates have steadily increased. Labor migration of husbands has increased household wealth and redefined women's roles, which have both positively and negatively impacted the health of wives "left behind". We examined the direct and indirect effects of husband labor migration on chronic disease indicators and outcomes among wives of labor migrants. METHODS: We collected survey, anthropometric, and biomarker data from a random sample of women in Matlab, Bangladesh, in 2018. We assessed associations between husband's migration and indicators of adiposity and chronic disease. We used structural equation modeling to assess the direct effect of labor migration on chronic disease, undernutrition, and adiposity, and the mediating roles of income, food security, and proportion of food purchased from the bazaar. Qualitative interviews and participant observation were used to help provide context for the associations we found in our quantitative results. FINDINGS: Among study participants, 9.0% were underweight, 50.9% were iron deficient, 48.3% were anemic, 39.6% were obese, 27.3% had a waist circumference over 35 in., 33.1% had a high whole-body fat percentage, 32.8% were diabetic, and 32.9% had hypertension. Slightly more women in the sample (55.3%) had a husband who never migrated than had a husband who had ever migrated (44.9%). Of those whose husband had ever migrated, 25.8% had a husband who was a current international migrant. Wives of migrants were less likely to be underweight, and more likely to have indicators of excess adiposity, than wives of non-migrants. Protection against undernutrition was attributable primarily to increased food security among wives of migrants, while increased adiposity was attributable primarily to purchasing a higher proportion of food from the bazaar; however, there was a separate path through income, which qualitative findings suggest may be related to reduced physical activity. CONCLUSIONS: Labor migration, and particularly international labor migration, intensifies the nutrition transition in Bangladesh through increasing wealth, changing how foods are purchased, and reducing physical activity, which both decreases risk for undernutrition and increases risk for excess adiposity.


Asunto(s)
Esposos , Migrantes , Bangladesh/epidemiología , Estudios Transversales , Emigración e Inmigración , Femenino , Humanos , Masculino , Obesidad , Población Rural , Factores Socioeconómicos , Delgadez/epidemiología
14.
Philos Trans R Soc Lond B Biol Sci ; 376(1827): 20200027, 2021 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-33938271

RESUMEN

Malnutrition among women of reproductive age is a significant public health concern in low- and middle-income countries. Of particular concern are undernutrition from underweight and iron deficiency, along with overweight and obesity, all of which have negative health consequences for mothers and children. Accumulating evidence suggests that risk for poor nutritional outcomes may be mitigated by social support, yet how social support is measured varies tremendously and its effects likely vary by age, kinship and reproductive status. We examine the effects of different measures of social support on weight and iron nutrition among 677 randomly sampled women from rural Bangladesh. While we find that total support network size mitigates risk for underweight, other results point to a potential tradeoff in the effects of kin proximity, with nearby adult children associated with both lower risk for underweight and obesity and higher risk for iron deficiency and anaemia. Social support from kin may then enhance energy balance but not diet quality. Results also suggest that a woman's network of caregivers might reflect their greater need for help, as those who received more help with childcare and housework had worse iron nutrition. Overall, although some findings support the hypothesis that social support can be protective, others emphasize that social relationships often have neutral or negative effects, illustrating the kinds of tradeoffs expected from an evolutionary perspective. The complexities of these effects deserve attention in future work, particularly within public health, where what is defined as 'social support' is often assumed to be positive. This article is part of the theme issue 'Multidisciplinary perspectives on social support and maternal-child health'.


Asunto(s)
Familia , Conducta Materna , Salud Materna , Madres , Estado Nutricional , Red Social , Apoyo Social , Adulto , Bangladesh , Peso Corporal , Femenino , Humanos , Hierro/fisiología , Persona de Mediana Edad , Madres/psicología , Madres/estadística & datos numéricos , Adulto Joven
15.
Biomed J ; 39(6): 376-381, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28043416

RESUMEN

BACKGROUND: Apium leptophyllum (Pers.) is an annual herb with traditional appreciation for various pharmacological properties; however, the scientific information on this herb is insufficient. The aim of the present investigation was undertaken to evaluate flavonoidal fraction of A. leptophyllum fruit (FFALF) against diarrhoea on albino rats. METHODS: The antidiarrhoeal study was conducted by castor oil induce diarrhoea, prostaglandin E2 (PGE2) induced enteropooling and intestinal transit by charcoal meal test. The rats were divided into five groups (six/group). Group I served as control and received orally 2% acacia suspension; Group II served as standard and received orally loperamide (3 mg/kg) or atropine sulphate (5 mg/kg); Group III, IV and V served as test groups and received the FFALF at doses of 5, 10 and 20 mg/kg orally, respectively. RESULTS: In castor oil-induced diarrhoeal model, the FFALF significantly (p < 0.001) reduced the frequency of diarrhoea, defecation and weight of faeces as well as increased the sodium-potassium ATPase (Na+K+ATPase) activity and decreased nitric oxide (NO) content in the small intestine. In prostaglandin induced enteropooling model, it significantly (p < 0.01) and dose dependently slowed the intestinal fluid accumulation by decreasing the masses and volumes of intestinal fluid where as in charcoal meal test, it decreased charcoal meal transit in gastrointestinal tract as compared with control. CONCLUSIONS: The study reveals that the FFALF possess anti-diarrhoeal properties mediated through inhibition of hyper secretion and gastrointestinal motility which support the traditional use of the plant.


Asunto(s)
Antidiarreicos/uso terapéutico , Apiaceae/química , Diarrea/tratamiento farmacológico , Motilidad Gastrointestinal/efectos de los fármacos , Extractos Vegetales/uso terapéutico , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Animales , Diarrea/inducido químicamente , Modelos Animales de Enfermedad , Femenino , Masculino , Óxido Nitroso/metabolismo , Ratas
16.
BMJ Case Rep ; 20132013 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-23761508

RESUMEN

Pleural malignant mesothelioma is an uncommon tumour of the thorax. We report two cases: a patient with atypically isolated location of the tumour at the right hilum and a young female patient. The histopathological and radiological features are reviewed with reference to relevant literature.


Asunto(s)
Neoplasias Pulmonares/diagnóstico por imagen , Mesotelioma/diagnóstico por imagen , Neoplasias Pleurales/diagnóstico por imagen , Adulto , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Mesotelioma/patología , Mesotelioma Maligno , Persona de Mediana Edad , Neoplasias Pleurales/patología , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X
17.
BMJ Case Rep ; 20122012 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-23047993

RESUMEN

A 31-year-old postal worker was diagnosed with bilateral thoracic outlet syndrome and scheduled for the first of two surgeries. The first procedure involved removal of the right first cervical rib, anterior and middle scalenes. On postoperative day 4, he developed shortness of breath. Chest radiograph showed a new pleural effusion on the right. Thoracentesis revealed a yellowish-red thick effusion. Based on the initial look of the fluid it was thought to be a haemorrhagic effusion with a purulent component, further testing revealed that he had developed a chylothorax. The patient was placed on a medium-chain triglyceride diet followed by chest tube drainage. After one day, the chest tube was removed due to minimal drainage, and he was discharged home the next day. Keeping this patient without food, on total parental nutrition, or pursuing surgical intervention was not necessary, as he had an excellent outcome from a very rare surgical complication.


Asunto(s)
Quilotórax/etiología , Disnea/etiología , Derrame Pleural/etiología , Complicaciones Posoperatorias , Síndrome del Desfiladero Torácico/cirugía , Adulto , Tubos Torácicos , Quilotórax/terapia , Grasas de la Dieta/administración & dosificación , Drenaje , Disnea/diagnóstico por imagen , Disnea/terapia , Humanos , Masculino , Derrame Pleural/terapia , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/terapia , Radiografía Torácica , Síndrome del Desfiladero Torácico/complicaciones , Síndrome del Desfiladero Torácico/diagnóstico por imagen , Triglicéridos/administración & dosificación
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