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1.
Am J Hematol ; 99(6): 1172-1174, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38436141

RESUMO

Probability of treatment-free remission (TFR) in CML patients with additional chromosomal abnormalities (ACA) in the Philadelphia-positive clone or variant Philadelphia translocations (ACA/Var-Ph group, blue panel), in those with no cytogenetic abnormality other than the classical Philadelphia translocation (c-Ph group, green panel) and in the subgroups of CML patients with high-risk ACA (HR-ACA, yellow panel) and Var-Ph (red panel).


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Cromossomo Filadélfia , Indução de Remissão , Translocação Genética , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Aberrações Cromossômicas , Idoso , Adolescente
2.
Nanotechnology ; 35(19)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38295411

RESUMO

The field-effect transistor (FET) is a fundamental component of semiconductors and the electronic industry. High on-current and mobility with layer-dependent features are required for outstanding FET channel material. Two-dimensional materials are advantageous over bulk materials owing to their higher mobility, high ON/OFF ratio, low tunneling current, and leakage problems. Moreover, two-dimensional heterostructures provide a better way to tune electrical properties. In this work, the two distinct possibilities of PdSe2/MoSe2heterostructure have been employed through mechanical exfoliation and analyzed their electrical response. These diffe approaches to heterostructure formation serve as crucial components of our investigation, allowing us to explore and evaluate the unique electronic properties arising from each design. This work demonstrates that the heterostructure possesses a better ON/OFF ratio of ∼5.78 × 105, essential in switching characteristics. Moreover, MoSe2provides a defect-free interface to PdSe2, resulting in a higher ON current of ∼10µA and mobility of ∼63.7 cm2V-1s-1, necessary for transistor applications. In addition, comprehending the process of charge transfer occurring at the interface between transition metal dichalcogenides is fundamental for advancing next-generation technologies. This work provides insights into the interface formed between the PdSe2and MoSe2that can be harnessed in transistor applications.

3.
Environ Res ; 244: 117939, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38128604

RESUMO

The Guerouaou aquifer investigation spanning 280 km2 in Ain Zohra yields promising outcomes, instilling optimism for regional water quality. These analyses were applied to 45 sampling instances from 43 wells, enabling a comprehensive water quality assessment. Groundwater conductivity ranged from medium to high, peaking at 18360 ms/cm2. The conductivity reveals insights about the groundwater's mineralization. Key physiochemical parameters fell within desirable thresholds, bolstering the positive perspective. HCO3- levels spanned 82-420 mg/L, while chloride content ranged from 38 to 5316 mg/L, benefiting water quality. NO3- ions, vital for gauging pollution, ranged from 0 to 260 mg/L, indicating favorable results. Cation concentrations exhibited encouraging variations: Ca2+- 24 to 647 mg/L, Mg2+- 12 to 440 mg/L, Na+- 18 to 2722 mg/L, K+- 1.75 to 28.65 mg/L. These collectively favor water quality. Halite breakdown dominated mineralization, as evidenced by the prevalence of Na-Cl-Na-SO4 facies. Water resource management and local communities need effective management and mitigation strategies to prevent saltwater intrusion.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Monitoramento Ambiental/métodos , Marrocos , Poluentes Químicos da Água/análise , Salinidade , Água Subterrânea/análise , Qualidade da Água
4.
J Comput Chem ; 44(23): 1875-1883, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37224190

RESUMO

This article presents detailed structural, electronic, magnetic, and thermoelectric properties of two experimentally existing isostructural variant perovskite compounds Tl2 NbX6 (X = Cl, Br) with the help of first principles calculations. As per requirement of stability in the device applications, the structural and thermodynamic stabilities were, respectively verified by tolerance factor and negative formation energies. The structural parameters in ferromagnetic phase were calculated and found in close agreement with the available experimental results. The electronic nature was found as half metallic from spin polarized calculations of electronic band structures and density of states, where the semiconductor nature was found in the spin down states and metallic nature in the spin up states. The magnetic moments of both the compounds were calculated as 1 µB majorly contributed by Nb atom. The Boltzmann transport theory was implemented via BoltzTraP for calculating the spin resolved thermoelectric parameters, such as Seebeck coefficient, electronic and thermal conductivities, and figure of merit. Overall, both the compounds were found suitable for use in spintronics and spin Seebeck effect for energy applications.

5.
Nanotechnology ; 35(11)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38081080

RESUMO

The importance of infrared photodetectors cannot be overstated, especially in fields such as security, communication, and military. While silicon-based infrared photodetectors are widely used due to the maturity of the semiconductor industry, their band gap of 1.12 eV limits their infrared light absorption above 1100 nm, making them less effective. To overcome this limitation, we report a novel infrared photodetector prepared by growing graphene on the surface of zinc hyper-doped silicon. This technique utilizes hyper-doping to introduce deep level assisted infrared light absorption benefit from the enhanced carrier collection capacity of graphene. Without introducing new energy consumption, the hyper-doped substrate annealing treatment is completed during the growth of graphene. By the improvement of transport and collection of charge carriers, the graphene growth adjusts the band structure to upgrade electrode contact, resulting in a response of 1.6 mA W-1under laser irradiation with a wavelength of 1550 nm and a power of 2 mW. In comparison, the response of the photodetector without graphene was only 0.51 mA W-1, indicating a three-fold performance improvement. Additionally, the device has lower dark current and lower noise current, resulting in a noise equivalent power of 7.6 × 10-8W Hz-0.5. Thus, the combination of transition metal hyper-doping and graphene growth technology has enormous potential for developing the next generation of infrared photodetectors.

6.
J Korean Med Sci ; 38(12): e88, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36974397

RESUMO

Plagiarism is one of the most frequent forms of research misconduct in South and East Asian countries. This narrative review examines the factors contributing to research misconduct, emphasizing plagiarism, particularly in South, East and Southeast Asian countries. We conducted a PubMed and Scopus search using the terms plagiarism, Asia, South Asia, East Asia, Southeast Asia, research misconduct and retractions in January of 2022. Articles with missing abstracts, incomplete information about plagiarism, publication dates before 2010, and those unrelated to South, East, and Southeast Asian countries were excluded. The retraction watch database was searched for articles retracted between 9th January 2020 to 9th January 2022. A total of 159 articles were identified, of which 21 were included in the study using the database search criteria mentioned above. The review of articles identified a lack of training in scientific writing and research ethics, publication pressure, permissive attitudes, and inadequate regulatory measures as the primary reasons behind research misconduct in scientific publications. Plagiarism remains a common cause of unethical publications and retractions in regions of Asia (namely South, East and Southeast). Researchers lack training in scientific writing, and substantial gaps exist in understanding various forms of plagiarism, which heavily contribute to the problem. There is an urgent need to foster high research ethics standards and adhere to journal policies. Providing appropriate training in scientific writing among researchers may help improve the knowledge of different types of plagiarism and promote the use of antiplagiarism software, leading to a substantial reduction in the problem.


Assuntos
Pesquisa Biomédica , Má Conduta Científica , Humanos , Plágio , PubMed , Redação , Ásia
7.
Luminescence ; 38(7): 1064-1086, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36378274

RESUMO

The penicillin derivative amoxicillin (AMX) plays an important role in treating various types of infections caused by bacteria. However, excessive use of AMX may have negative health effects. Therefore, it is of utmost importance to detect and quantify the AMX in pharmaceutical drugs, biological fluids, and environmental samples with high sensitivity. Therefore, this review article provides valuable and up-to-date information on nanostructured material-based optical and electrochemical sensors to detect AMX in various biological and chemical samples. The role of using different nanostructured materials on the performance of important optical sensors such as colorimetric sensors, fluorescence sensors, surface-enhanced Raman scattering sensors, chemiluminescence/electroluminescence sensors, optical immunosensors, optical fibre-based sensors, and several important electrochemical sensors based on different electrode types have been discussed. Moreover, nanocomposites, polymer, and MXenes-based electrochemical sensors have also been discussed, in which such materials are being used to further enhance the sensitivity of these sensors. Furthermore, nanocomposite-based photo-electrochemical sensors and the market availability of biosensors including AMX have also been discussed briefly. Finally, the conclusion, challenges, and future perspectives of the above-mentioned sensing techniques for AMX detection are presented.


Assuntos
Técnicas Biossensoriais , Nanocompostos , Antibacterianos , Amoxicilina , Técnicas Biossensoriais/métodos , Imunoensaio , Técnicas Eletroquímicas/métodos
8.
Phytother Res ; 37(3): 1136-1152, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36592613

RESUMO

In Asia, mulberry has long been used to treat various infectious and internal ailments as a traditional medication. The compounds found in it have the potential to improve human health. Because there is no approved and defined evaluation procedure, it has not been formally or scientifically recognized. As a result of these investigations, a new frontier in traditional Chinese medicine has opened up, with the possibility of modernization, for the interaction between active components of mulberry and their biological activities. These studies have used current biotechnological technologies. For ages, mulberry has been used as an herbal remedy in Asia to cure various diseases and internal disorders. It has a high concentration of bioactive chemicals that benefit human health. The most abundant phenolic components extracted from white mulberry leaves are flavonoids (Kuwanons, Moracinflavans, Moragrols, and Morkotins), phenolic acids, alkaloids, and so forth. Flavonoids, benzofurans, chalcones, and alkaloids have been discovered to have cytotoxic effects on human cancer cell lines. There is growing evidence that mulberry fruits can potentially prevent cancer and other aging-related disorders due to their high concentration of bioactive polyphenolic-rich compounds and macro and micronutrients. Anthocyanins are rapidly absorbed after eating, arriving in the plasmalemma within 15-50 min and entirely removed after 6-8 hr. Due to a lack of an approved and consistent technique for its examination, it has yet to be formally or scientifically recognized. The mulberry plant is commercially grown for silkworm rearing, and less attention is paid to its bioactive molecules, which have a lot of applications in human health. This review paper discusses the phenolic compounds of white mulberry and black mulberry in detail concerning their role in cancer prevention.


Assuntos
Morus , Neoplasias , Humanos , Antocianinas/química , Frutas/química , Morus/química , Fenóis/química , Flavonoides/química
9.
J Environ Manage ; 342: 118331, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37315466

RESUMO

Implementing unified municipal solid waste management (MSWM) is often difficult due to socio-economic variables. However, spatial GIS models and statistical analysis of solid waste characterized by the weekdays, weekends, and festivals can somewhat mitigate the variance and assist with selecting suitable waste management methods. This paper presents the example of Rajouri, India, to propose a suitable MSWM based on Inverse Distance Weighted (IDW) intensity maps and statistical findings. The considered region was divided into different sample sites based on the local population density, and Municipal Solid Waste (MSW) was collected from four locations in each site on weekdays, weekends, and festivals. Compositional analysis of the MSW was then used to generate spatial IDW models in QGIS 3.22.7 to interpolate MSW generation over the entire area. Finally, statistical analysis was conducted to gain insight into the waste generation and accumulation trends. The results show that Rajouri produces 245 tonnes of waste daily (per capita: 0.382 kg/day) with a large organic fraction compared to other waste categories. Besides, waste generation is observed to increase over weekends and festivals due to increased consumption of material goods. Composting could serve as a vector for municipal solid waste because of its increased organic component and cost constraints. However, further research on the potential segregation techniques for the organic fraction of solid waste is needed.


Assuntos
Compostagem , Eliminação de Resíduos , Gerenciamento de Resíduos , Resíduos Sólidos/análise , Eliminação de Resíduos/métodos , Gerenciamento de Resíduos/métodos , Índia , Cidades
10.
Nanotechnology ; 33(50)2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36044876

RESUMO

Hydrogenated graphene is easy to prepare and chemically stable. Besides, hydrogenation of graphene can open the band gap, which is vital for electronic and optoelectronic applications. Graphene/Si photodetector (PD) has been widely studied in imaging, telecommunications, and other fields. The direct contact between graphene and Si can form a Schottky junction. However, it suffers from poor interface state, where the carrier recombination at the interface causes serious leakage current, which in turn leads to a decrease in the detectivity. Hence, in this study, hydrogenated graphene is used as an interfacial layer, which passivates the interface of graphene/Si (Gr/Si) heterostructure. Besides, the single atomic layer thickness of hydrogenated graphene is also crucial for the tunneling transport of charge carriers and its suitable energy band position reduces the recombination of carrier. The fabricated graphene/hydrogenated-graphene/Si (Gr/H-Gr/Si) heterostructure PD showed an extremely low dark current about 10-7A. As a result, it had low noise current and exhibited a high specific detectivity of âˆ¼2.3 × 1011Jones at 0 V bias with 532 nm laser illumination. Moreover, the responsivity of the fabricated PD was found to be 0.245 A W-1at 532 nm illumination with 10µW power. These promising results show a great potential of hydrogenated graphene to be used as an interface passivation and carrier tunneling layer for the fabrication of high-performance Gr/Si heterostructure PDs.

11.
Environ Res ; 204(Pt C): 112243, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34688648

RESUMO

In the last three decades, pharmaceutical research has increased tremendously to offer safe and healthy life. However, the high consumption of these harmful drugs has risen devastating impact on ecosystems. Therefore, it is worldwide paramount concern to effectively clean pharmaceuticals contaminated water streams to ensure safer environment and healthier life. Nanotechnology enables to produce new, high-technical material, such as membranes, adsorbent, nano-catalysts, functional surfaces, coverages and reagents for more effective water and wastewater cleanup processes. Nevertheless, nano-sorbent materials are regarded the most appropriate treatment technology for water and wastewater because of their facile application and a large number of adsorbents. Several conventional techniques have been operational for domestic wastewater treatment but are inefficient for pharmaceuticals removal. Alternatively, adsorption techniques have played a pivotal role in water and wastewater treatment for a long, but their rise in attraction is proportional with the continuous emergence of new micropollutants in the aquatic environment and new discoveries of sustainable and low-cost adsorbents. Recently, advancements in adsorption technique for wastewater treatment through nanoadsorbents has greatly increased due to its low production cost, sustainability, better physicochemical properties and high removal performance for pharmaceuticals. Herein, this review critically evaluates the performance of sustainable green nanoadsorbent for the remediation of pharmaceutical pollutants from water. The influential sorption parameters and interaction mechanism are also discussed. Moreover, the future prospects of nanoadsorbents for the remediation of pharmaceuticals are also presented.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Ecossistema , Preparações Farmacêuticas , Águas Residuárias/análise , Água , Poluentes Químicos da Água/análise
12.
Environ Res ; 215(Pt 1): 114224, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36058276

RESUMO

Microplastics are a silent threat that represent a high degree of danger to the environment in its different ecosystems and of course will also have an important impact on the health of living organisms. It is evident the need to have effective treatments for their treatment, however this is not a simple task, this as a result of the behavior of microplastics in wastewater treatment plants due to their different types and nature, their long molecular chain, reactivity against water, size, shape and the functional groups they carry. Wastewater treatment plants are at the circumference of the release of these wastes into the environment. They often act as a source of many contaminations, which makes this problem more complex. Challenges such as detection in the current scenario using the latest analytical techniques impede the correct understanding of the problem. Due to microplastics, treatment plants have operational and process stability problems. This review paper will present the in-depth situation of occurrence of microplastics, their detection, conventional and advanced treatment methods as well as implementation of legislations worldwide in a comprehensive manner. It has been observed that no innovative or new technologies have emerged to treat microplastics. Therefore, in this article, technologies targeting wastewater treatment plants are critically analyzed. This will help to understand their fate, but also to develop state-of-the-art technologies or combinations of them for the selective treatment of microplastics. The pros and cons of the treatment methods adopted and the knowledge gaps in legislation regarding their implementation are also comprehensively analyzed. This critical work will offer the development of new strategies to restrict microplastics.


Assuntos
Microplásticos , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental/métodos , Microplásticos/toxicidade , Plásticos , Águas Residuárias/análise , Água , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
13.
Molecules ; 27(22)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36432031

RESUMO

Iron oxide nanoparticle (ION)-based ferro-nanofluids (FNs) have been used for different technological applications owing to their excellent magneto-rheological properties. A comprehensive overview of the current advancement of FNs based on IONs for various engineering applications is unquestionably necessary. Hence, in this review article, various important advanced technological applications of ION-based FNs concerning different engineering fields are critically summarized. The chemical engineering applications are mainly focused on mass transfer processes. Similarly, the electrical and electronics engineering applications are mainly focused on magnetic field sensors, FN-based temperature sensors and tilt sensors, microelectromechanical systems (MEMS) and on-chip components, actuators, and cooling for electronic devices and photovoltaic thermal systems. On the other hand, environmental engineering applications encompass water and air purification. Moreover, mechanical engineering or magneto-rheological applications include dampers and sealings. This review article provides up-to-date information related to the technological advancements and emerging trends in ION-based FN research concerning various engineering fields, as well as discusses the challenges and future perspectives.


Assuntos
Eletrônica , Sistemas Microeletromecânicos , Tecnologia , Eletricidade , Nanopartículas Magnéticas de Óxido de Ferro
14.
Br J Haematol ; 193(2): 346-355, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33368155

RESUMO

Targeted therapy for chronic myeloid leukaemia (CML) has allowed for a near-normal patient life-expectancy; however, quality of life and aggravation of existing co-morbidities have posed new treatment challenges. In clinical practice, TKI dose reduction occurs frequently, often on multiple occasions, because of intolerance. We conducted a retrospective 'real-world practice' review of 246 patients receiving lower than standard dose (LD) TKI after the achievement of major molecular response (MR3), because of intolerable adverse events. In 274 of 298 cases of dose reduction (91·9%), MR3 was maintained at median follow-up of 27·3 months. One patient progressed to blast crisis while on LD TKI. Two patients developed two new ABL kinase domain mutations (T315I and V299L), of whom one had achieved deep molecular response on an alternative LD TKI at last follow-up. Seventy-six patients eventually discontinued LD TKI and the two-year treatment-free remission (TFR) rate in these patients was 74·1%. The majority of patients with CML in at least MR3 appear to be safely managed with LD TKI, although three of 246 patients had new events (progression and new mutation), indicating that this approach requires vigilance. TKI LD does not prevent the achievement of TFR in this patient population.


Assuntos
Redução da Medicação/métodos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Indução de Remissão/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Compostos de Anilina/administração & dosagem , Compostos de Anilina/efeitos adversos , Compostos de Anilina/uso terapêutico , Comorbidade , Dasatinibe/administração & dosagem , Dasatinibe/efeitos adversos , Dasatinibe/uso terapêutico , Feminino , Seguimentos , Proteínas de Fusão bcr-abl/genética , Humanos , Mesilato de Imatinib/administração & dosagem , Mesilato de Imatinib/efeitos adversos , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Masculino , Pessoa de Meia-Idade , Mutação , Nitrilas/administração & dosagem , Nitrilas/efeitos adversos , Nitrilas/uso terapêutico , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/efeitos adversos , Pirimidinas/administração & dosagem , Pirimidinas/efeitos adversos , Pirimidinas/uso terapêutico , Qualidade de Vida , Quinolinas/administração & dosagem , Quinolinas/efeitos adversos , Quinolinas/uso terapêutico , Estudos Retrospectivos , Segurança , Resultado do Tratamento
15.
Nanotechnology ; 32(42)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34252891

RESUMO

Ferrofluids or magnetic nanofluids are highly stable colloidal suspensions of magnetic nanoparticles (NPs) dispersed into various base fluids. These stable ferrofluids possess high thermal conductivity, improved thermo-physical properties, higher colloidal stability, good magnetic properties, and biocompatibility, which are the primary driving forces behind their excellent performance, and thus enable them to be used for a wide range of practical applications. The most studied and advanced ferrofluids are based on iron oxide nanostructures especially NPs, because of their easy and large-scale synthesis at low costs. Although in the last decade, several review articles are available on ferrofluids but mainly focused on preparations, properties, and a specific application. Hence, a collective and comprehensive review article on the recent progress of iron oxide nanostructures based ferrofluids for advanced biomedical applications is undeniably required. In this review, the state of the art of biomedical applications is presented and critically analyzed with a special focus on hyperthermia, drug delivery/nanomedicine, magnetic resonance imaging, and magnetic separation of cells. This review article provides up-to-date information related to the technological advancements and emerging trends in iron oxide nanostructures based ferrofluids research focused on advanced biomedical applications. Finally, conclusions and outlook of iron oxide nanostructures based ferrofluids research for biomedical applications are presented.

16.
Environ Res ; 200: 111373, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34033834

RESUMO

The recent spread of severe acute respiratory syndrome coronavirus (SAR-CoV-2) and the accompanied coronavirus disease 2019 (COVID-19) has continued ceaselessly despite the implementations of popular measures, which include social distancing and outdoor face masking as recommended by the World Health Organization. Due to the unstable nature of the virus, leading to the emergence of new variants that are claimed to be more and rapidly transmissible, there is a need for further consideration of the alternative potential pathways of the virus transmissions to provide the needed and effective control measures. This review aims to address this important issue by examining the transmission pathways of SARS-CoV-2 via indirect contacts such as fomites and aerosols, extending to water, food, and other environmental compartments. This is essentially required to shed more light regarding the speculation of the virus spread through these media as the available information regarding this is fragmented in the literature. The existing state of the information on the presence and persistence of SARS-CoV-2 in water-food-environmental compartments is essential for cause-and-effect relationships of human interactions and environmental samples to safeguard the possible transmission and associated risks through these media. Furthermore, the integration of effective remedial measures previously used to tackle the viral outbreaks and pandemics, and the development of new sustainable measures targeting at monitoring and curbing the spread of SARS-CoV-2 were emphasized. This study concluded that alternative transmission pathways via human interactions with environmental samples should not be ignored due to the evolving of more infectious and transmissible SARS-CoV-2 variants.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Pandemias , Água
17.
Environ Chem Lett ; 19(4): 2773-2787, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33846683

RESUMO

End 2019, the zoonotic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), named COVID-19 for coronavirus disease 2019, is the third adaptation of a contagious virus following the severe acute respiratory syndrome coronavirus in 2002, SARS-CoV, and the Middle East respiratory syndrome virus in 2012, MERS-CoV. COVID-19 is highly infectious and virulent compared to previous outbreaks. We review sources, contagious routes, preventive measures, pandemic, outbreak, epidemiology of SARS-CoV, MERS-CoV and SARS-CoV-2 from 2002 to 2020 using a Medline search. We discuss the chronology of the three coronaviruses, the vulnerability of healthcare workers, coronaviruses on surface and in wastewater, diagnostics and cures, and measures to prevent spreading.

18.
Nanotechnology ; 31(6): 065401, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-31627206

RESUMO

Hole transporting layers (HTLs) play a crucial role in the realization of efficient and stable perovskite solar cells (PSCs). Copper phthalocyanine (CuPc) is a promising HTL owing to its thermal stability and favorable band alignment with the perovskite absorber. However, the power conversion efficiency (PCE) of PSCs with a CuPc HTL is still lagging behind highly efficient solar cells. Herein, a p-type tetrafluoro-tetracyanoquinodimethane (F4-TCNQ) is employed as an interlayer between the perovskite and CuPc HTL in all-vacuum deposited PSCs. The F4-TCNQ interlayer improves the conductivity of both MAPbI3 and CuPc, reduces the shunt pathway and facilitates an efficient photoexcited holes transfer from the valance band of the MAPbI3 to the LUMO of the F4-TCNQ. Consequently, the best solar cell device with an F4-TCNQ interlayer achieved a PCE of 13.03% with a remarkable improvement in fill factor. Moreover, the device showed superior stability against thermal stress at 85 °C over 250 h and retained ∼95% of its initial efficiency. This work demonstrates a significant step towards all-vacuum deposited perovskite solar cells with high thermal stability.

19.
Langmuir ; 34(18): 5214-5224, 2018 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-29656649

RESUMO

Superhydrophobic surfaces can be fabricated by using the self-assembled nanoarchitecture of 3C-SiC one-dimensional (1D) nanostructures as they are capable of forming a dense network of micro-nano air pockets without any help from external sources. Herein, the metal-catalyzed growth of 3C-SiC nanowires/nanorods on Si substrates via vapor-liquid-solid mechanism using five different catalysts, that is, chemically synthesized Au nanoparticles and direct current-sputtered thin films of Au, Cu, Ni, and Ti, is reported. Relatively new or unexplored catalysts such as thin films of Cu and Ti, as well as drop-cast Au nanoparticles, were used. An optimized and separate growth was carried out for each catalyst in an inductively heated horizontal cold-wall atmospheric pressure chemical vapor deposition reactor. An insight into the catalytic growth mechanism of 3C-SiC 1D nanostructures has been presented. All of the bare samples exhibited superhydrophilic behavior, whereas hierarchical Au/Pd nanostructure-coated 3C-SiC nanorod samples grown using Au and Ni thin-film catalysts exhibited hydrophobic and superhydrophobic behavior, respectively. As the better results were obtained for Ni thin-film catalysts in terms of growth density and high water contact angle (WCA ≈ 160°), therefore, the growth temperature, as well as the growth time-dependent wetting behavior, was also studied. It was found that the WCA increased as the growth time and temperature increased because of the increase in the growth density, and it finally reached to an optimum value at the growth temperature of 1200 °C and the growth time of 1 h. Furthermore, their wetting behavior was studied by using a variety of high surface tension (water, milk, tea, and glycerin) and low surface tension (organic liquids such as n-hexane, ethanol, etc.) liquids. High surface tension liquids exhibited superhydrophobic behavior, whereas low surface tension liquids exhibited superhydrophilic behavior. Hence, these fabricated nanostructured surfaces can be exploited for oil-water separation, electrowetting, water harvesting, self-cleaning, lab on a chip, and micro-/nanofluidic device applications.

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