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1.
Artigo em Inglês | MEDLINE | ID: mdl-38743851

RESUMO

Copper oxide appears to be a promising candidate for a hole transport layer (HTL) in emerging perovskite solar cells. Reasons for this are its good optical and electrical properties, cost-effectiveness, and high stability. However, is this really the case? In this study, we demonstrate that copper oxide, synthesized by a spray-coating method, is unstable in contact with formamidinium lead triiodide (FAPI) perovskite, leading to its decomposition. Using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and ultraviolet-visible (UV-vis) spectrophotometry, we find that the entire copper oxide diffuses into and reacts with the FAPI film completely. The reaction products are an inactive yellow δ-FAPI phase, copper iodide (CuI), and an additional new phase of copper formate hydroxide (CH2CuO3) that has not been reported previously in the literature.

2.
Molecules ; 28(21)2023 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-37959745

RESUMO

In this report, the morphological, optical, electrical, and photovoltaic properties of copper oxide and calcium-doped copper oxide thin films produced via the spray coating method were studied. The thermal post treatment at 300 °C in an inert atmosphere allowed us to obtain a single phase of Cu2O with 21 Ωcm of resistivity (ρ). In this study, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, and 10 wt% Ca admixtures with copper oxide were investigated. The determined optimal calcium dopant concentration was 4 wt%. XRD analysis was used to reveal the chemical composition of the produced layers. It was found that a calcium dopant does not change the layer composition but improves its electrical parameters. Based on UV-Vis spectra, the band gap energy and Urbach energy were calculated. The morphology of produced thin films was described as smooth and nanocrystalline, corresponding to a grain size calculated based on the Scherrer equation. Finally, it was shown that the developed protocol of low-resistivity copper oxide deposition via the spray coating technique can be successfully implemented in heterojunction solar cell production. The I-V parameters of Ag/n-type CzSi/REF:CuOx and 4Ca:CuOx/Carbon were collected, and the achieved efficiency was 2.38%.

3.
Folia Med Cracov ; 63(2): 107-134, 2023 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-37903383

RESUMO

Drug-abuse detection tests are becoming increasingly commonplace in patient care today and provide a rapid and effective method for identifying illicit substances. Occasionally, they may yield a positive result, indicating the presence of a substance, even though the individual has not consumed the suspected drug what sometimes can significantly impact both medical and legal decisions. The study outlines the substances that can lead to false-positive drug test results for amphetamines, cannabinoids, and benzodiazepines. The study's findings have revealed pivotal insights for patients receiving chronic treatment and their primary care physicians. Notably, amphetamine assays appear to be most prone to cross-reactivity with other substances. The beta-blocker group of medications, confirmed by various studies to interfere with amphetamine assays, could pose a substantial challenge in drug screening given its widespread use. Efavirenz also warrants mention, as it frequently triggers positive results for both benzodiazepine and cannabinoid assays among its users. This research helps highlight new areas for further investigation and aims to guide clinicians in their daily practice, especially when interpreting questionable positive drug-abuse test results. This comprehensive review serves as a valuable resource for clinicians to navigate false-positive scenarios effectively and maintain the highest standard of patient care.


Assuntos
Anfetamina , Detecção do Abuso de Substâncias , Humanos , Detecção do Abuso de Substâncias/métodos
4.
Sci Total Environ ; 896: 165081, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37355122

RESUMO

Typology systems are frequently used in applied and fundamental ecology and are relevant for environmental monitoring and conservation. They aggregate ecosystems into discrete types based on biotic and abiotic variables, assuming that ecosystems of the same type are more alike than ecosystems of different types with regard to a specific property of interest. We evaluated whether this assumption is met by the Broad River Types (BRT), a recently proposed European river typology system, that classifies river segments based on abiotic variables, when it is used to group biological communities. We compiled data on the community composition of diatoms, fishes, and aquatic macrophytes throughout Europe and evaluated whether the composition is more similar in site groups with the same river type than in site groups of different river types using analysis of similarities, classification strength, typical species analysis, and the area under zeta diversity decline curves. We compared the performance of the BRT with those of four region-based typology systems, namely, Illies Freshwater Ecoregions, the Biogeographic Regions, the Freshwater Ecoregions of the World, and the Environmental Zones, as well as spatial autocorrelation (SA) classifications. All typology systems received low scores from most evaluation methods, relative to predefined thresholds and the SA classifications. The BRT often scored lowest of all typology systems. Within each typology system, community composition overlapped considerably between site groups defined by the types of the systems. The overlap tended to be the lowest for fishes and between Illies Freshwater Ecoregions. In conclusion, we found that existing broad-scale river typology systems fail to delineate site groups with distinct and compositionally homogeneous communities of diatoms, fishes, and macrophytes. A way to improve the fit between typology systems and biological communities might be to combine segment-based and region-based typology systems to simultaneously account for local environmental variation and historical distribution patterns, thus potentially improving the utility of broad-scale typology systems for freshwater biota.


Assuntos
Diatomáceas , Ecossistema , Animais , Rios , Peixes , Monitoramento Ambiental/métodos
5.
Materials (Basel) ; 16(4)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36836993

RESUMO

The paper presents the results concerning the influence of the thickness of the ITO and In2O3 layers deposited by the magnetron sputtering method on the physical parameters characterising their surface properties. The characterisation parameters were obtained by atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and Kelvin probe. The increase in the layers' thickness related to the time of their fabrication causes an increase in the surface roughness and the value of the work function, followed by a decrease in the concentration of elements and compounds in the near-surface area.

6.
Sci Total Environ ; 842: 156689, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-35724793

RESUMO

Humans have severely altered freshwater ecosystems globally, causing a loss of biodiversity. Regulatory frameworks, like the Water Framework Directive, have been developed to support actions that halt and reverse this loss. These frameworks use typology systems that summarize freshwater ecosystems into environmentally delineated types. Within types, ecosystems that are minimally impacted by human activities, i.e., in reference conditions, are expected to be similar concerning physical, chemical, and biological characteristics. This assumption is critical when water quality assessments rely on comparisons to type-specific reference conditions. Lyche Solheim et al. (2019) developed a pan-European river typology system, the Broad River Types, that unifies the national Water Framework Directive typology systems and is gaining traction within the research community. However, it is unknown how similar biological communities are within these individual Broad River Types. We used analysis of similarities and classification strength analysis to examine if the Broad River Types delineate distinct macroinvertebrate communities across Europe and whether they outperform two ecoregional approaches: the European Biogeographical Regions and Illies' Freshwater Ecoregions. We determined indicator and typical taxa for the types of all three typology systems and evaluated their distinctiveness. All three typology systems captured more variation in macroinvertebrate communities than random combinations of sites. The results were similar among typology systems, but the Broad River Types always performed worse than either the Biogeographic Regions or Illies' Freshwater Ecoregions. Despite reaching statistical significance, the statistics of analysis of similarity and classification strength were low in all tests indicating substantial overlap among the macroinvertebrate communities of different types. We conclude that the Broad River Types do not represent an improvement upon existing freshwater typologies when used to delineate macroinvertebrate communities and we propose future avenues for advancement: regionally constrained types, better recognition of intermittent rivers, and consideration of biotic communities.


Assuntos
Ecossistema , Rios , Animais , Biodiversidade , Monitoramento Ambiental/métodos , Humanos , Invertebrados
7.
Materials (Basel) ; 14(4)2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33671703

RESUMO

In this work, we present the results of defects analysis concerning ZnO and Al2O3 layers deposited by atomic layer deposition (ALD) technique. The analysis was performed by the X-band electron paramagnetic resonance (EPR) spectroscopy, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) methods. The layers were either tested as-deposited or after 30 min heating at 300 °C and 450 °C in Ar atmosphere. TEM and XPS investigations revealed amorphous nature and non-stoichiometry of aluminum oxide even after additional high-temperature treatment. EPR confirmed high number of defect states in Al2O3. For ZnO, we found the as-deposited layer shows ultrafine grains that start to grow when high temperature is applied and that their crystallinity is also improved, resulting in good agreement with XPS results which indicated lower number of defects on the layer surface.

8.
Materials (Basel) ; 13(17)2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32867399

RESUMO

This paper presents results from the production of copper oxide layers on a Cu sheet substrate using diode and Yb:YAG disc lasers operating in the wavelength ranges of 808-940 nm and 1030 nm. The parameters of these layers were compared with the layer obtained in the thermal process of copper oxidation at 300 °C in an infrared (IR) furnace in a natural atmosphere. Investigations into the layers mentioned above, concerning their topography, chemical composition and roughness, were made using scanning electron microscopy (SEM) and atomic force microscopy (AFM). A hot-point probe was used to determine and check the type of conductivity of the copper oxide layers formed. The optical band gap energy was estimated by applying the Kubelka-Munk method based on spectrophotometric data. Cross-sections and the element distribution maps were made using transmission electron microscopy (TEM). The phase analysis was investigated by the X-ray diffraction method (XRD). In sum, controlled laser oxidations of copper sheets allow for the formation of a mixture of Cu2O and CuO phases. The diode laser allows the production of a layer of copper oxides with a phase composition comparable to the oxides produced by the thermal oxidation method, while the distribution of high phase uniformity in the cross-section of the layer enables the process using a Yb:YAG disc laser.

9.
Materials (Basel) ; 12(3)2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30682819

RESUMO

This work presents comparison results of the selected electrical parameters of silicon solar cells manufactured with silver front electrodes which were co-fired in an infrared belt furnace in the temperature range of 840⁻960 °C. The commercial paste (PV19B) was used for the metallization process. Electrical properties of a batch of solar cells fabricated in one cycle were investigated. Three methods were used, including measurement of the current-voltage characteristics (I-V), measurement of contacts' resistivity using the transmission Line model method (TLM), and measurement of contacts' resistivity using the potential difference method (PD). This work is focused on both the different metallization temperatures of co-firing of solar cells and measurements using the above-mentioned methods. It is shown that the solar cell parameters measured with three methods have different, but strongly correlated values. Moreover, the comparative analysis was performed of the investigations of the same photovoltaic solar cells using both the TLM method and independent research stands (including one non-commercial and two commercial ones) at three different scientific units. In the PD and TLM methods, the same calculation formulae are used. It can be stated, comparing methods I-V, PD, and TLM, that for each, different parameters are determined to assess the electrical properties of the solar cell.

10.
Materials (Basel) ; 11(12)2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30544599

RESUMO

In this work we present research results on a new paste NPCuXX (where: NP-new paste, CuXX-component, XX-a modifier consisting of Ni and other important elements) based on a copper composite (CuXX) for fabrication of front electrodes in silicon solar cells. The CuXX composite is obtained by chemical processing of copper powder particles and can be used in two ways: as an additive to commercially available paste or as a base material for a new paste, NPCuXX. The CuXX offers the possibility to exchange up to 30 and 50 wt.% Ag into Cu, which significantly decreases the solar cells material costs, and therefore, the overall solar cell price. Emphasis was placed on a proper mass suitable fabrication process of the CuXX component. The NPCuXX paste has been applied both to conventional cell structures such as aluminum-back surface field (Al-BSF) and passivated emitter and rear contact (PERC), and finally solar cells with front electrodes deposited by screen-printing method were fabricated and characterized by current-voltage techniques. This paper reports the first implementation of the copper volumetric material into a screen print paste used in a high-temperature metallization process to fabricate the front contacts of Si solar cells with a highest fill factor of 77.92 and 77.69% for the abovementioned structures, respectively.

11.
J Plant Physiol ; 228: 178-188, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29945073

RESUMO

Miscanthus × giganteus and Zea mays, closely-related C4 grasses, originated from warm climates react differently to low temperature. To investigate the response to cold (12-14 °C) in these species, the photosynthetic and anatomical parameters as well as biochemical properties of the cell wall were studied. The research was performed using M. giganteus (MG) and two Z. mays lines differentiated for chilling-sensitivity: chilling-tolerant (Zm-T) and chilling-sensitive (Zm-S). The chilled plants of Zm-S line demonstrated strong inhibition of net CO2 assimilation and a clear decrease in F'v/F'm, Fv/Fm and ɸPSII, while in MG and Zm-T plants these parameters were almost unchanged. The anatomical studies revealed that MG plants had thinner leaves, epidermis and mesophyll cell layer as well as thicker cell walls in the comparison to both maize lines. Cold led to an increase in leaf thickness and mesophyll cell layer thickness in the Zm-T maize line, while the opposite response was observed in Zm-S. In turn, in chilled plants of MG and Zm-T lines, some anatomical parameters associated with bundle sheath cells were higher. In addition, Zm-S line showed the strong increase in the cell wall thickness at cold for mesophyll and bundle sheath cells. Chilling-treatment induced the changes in the cell wall biochemistry of tested species, mainly in the content of glucuronoarabinoxylan, uronic acid, ß-glucan and phenolic compounds. This work presents a new approach in searching of mechanism(s) of tolerance/sensitivity to low temperature in two thermophilic plants: Miscanthus and maize.


Assuntos
Folhas de Planta/metabolismo , Poaceae/metabolismo , Zea mays/metabolismo , Clorofila/metabolismo , Temperatura Baixa , Regulação da Expressão Gênica de Plantas , Folhas de Planta/fisiologia , Poaceae/fisiologia , Zea mays/fisiologia
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