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1.
Nanomaterials (Basel) ; 14(7)2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38607150

RESUMO

Broad adoption has already been started of MXene materials in various energy storage technologies, such as super-capacitors and batteries, due to the increasing versatility of the preparation methods, as well as the ongoing discovery of new members. The essential requirements for an excellent anode material for lithium-ion batteries (LIBs) are high safety, minimal volume expansion during the lithiation/de-lithiation process, high cyclic stability, and high Li+ storage capability. However, most of the anode materials for LIBs, such as graphite, SnO2, Si, Al, and Li4Ti5O12, have at least one issue. Hence, creating novel anode materials continues to be difficult. To date, a few MXenes have been investigated experimentally as anodes of LIBs due to their distinct active voltage windows, large power capabilities, and longer cyclic life. The objective of this review paper is to provide an overview of the synthesis and characterization characteristics of the MXenes as anode materials of LIBs, including their discharge/charge capacity, rate performance, and cycle ability. In addition, a summary of the potential outlook for developments of these materials as anodes is provided.

2.
Nanomaterials (Basel) ; 12(17)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36079968

RESUMO

Recently, lithium-ion batteries (LIBs) have been widely employed in automobiles, mining operations, space applications, marine vessels and submarines, and defense or military applications. As an anode, commercial carbon or carbon-based materials have some critical issues such as insufficient charge capacity and power density, low working voltage, deadweight formation, short-circuiting tendency initiated from dendrite formation, device warming up, etc., which have led to a search for carbon alternatives. Transition metal oxides (TMOs) such as NiO as an anode can be used as a substitute for carbon material. However, NiO has some limitations such as low coulombic efficiency, low cycle stability, and poor ionic conductivity. These limitations can be overcome through the use of different nanostructures. This present study reviews the integration of the electrochemical performance of binder involved nanocomposite of NiO as an anode of a LIB. This review article aims to epitomize the synthesis and characterization parameters such as specific discharge/charge capacity, cycle stability, rate performance, and cycle ability of a nanocomposite anode. An overview of possible future advances in NiO nanocomposites is also proposed.

3.
Nanomaterials (Basel) ; 12(12)2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35745373

RESUMO

Lithium-ion batteries (LIBs) are undeniably the most promising system for storing electric energy for both portable and stationary devices. A wide range of materials for anodes is being investigated to mitigate the issues with conventional graphite anodes. Among them, TiO2 has attracted extensive focus as an anode candidate due to its green technology, low volume fluctuations (<4%), safety, and durability. In this review, the fabrication of different TiO2 nanostructures along with their electrochemical performance are presented. Different nanostructured TiO2 materials including 0D, 1D, 2D, and 3D are thoroughly discussed as well. More precisely, the breakthroughs and recent developments in different anodic oxidation processes have been explored to identify in detail the effects of anodization parameters on nanostructure morphology. Clear guidelines on the interconnected nature of electrochemical behaviors, nanostructure morphology, and tunable anodic constraints are provided in this review.

4.
Prog Biomater ; 10(4): 299-308, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34784015

RESUMO

Despite the importance of porous titanium oxide (PA-TiO2) in diverse functional applications, very little information is available on the compatible mechanical properties for potential biomedical applications. In this study, PA-TiO2 foam was synthesized using space-holding powder metallurgy and sintering methods to produce interconnected opened-cell structure with surface morphology of mountain-like features associated with the extensive rift valley system. Three different types of PA-TiO2 foams with porosities of 35-52% and mean pore diameter of 190-210 µm were fabricated for evaluating the effect of porosity on mechanical properties of bulk PA-TiO2. The modulus of elasticity of PA-TiO2 foams exhibited in the range of 45-262 MPa which was within the range of modulus of elasticity of human cancellous bone. Cytotoxicity test is performed in vitro analysis to observe the effect of cell toxicity to produce osteointegration when used as implantable materials. There was no cytotoxicity effect found and remarkable cell growth was observed for human cancerous (HeLa) cell line. However, there was no cytotoxicity effect found and cell growth was not observed for Vero cell line. This study suggested that PA-TiO2 facilitates cell growth without spreading toxicity and has mechanical properties of cancellous bone. Hence, it has potential application as implant and medical devices in biomedical applications.

5.
Heliyon ; 7(2): e06163, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33718635

RESUMO

Due to some of the limitations of monetary measures, various non-monetary approaches for assessing household wealth have been developed as alternative tools for classifying household socio-economic status. Among them, wealth indices based on household durable assets are being used. The literature revealed that two basic methods of constructing wealth indices are employed: an unweighted method, where assets are weighted equally; and a weighted method, where specific weights are assigned to assets. In the case of using the weighted method, weighting can be assigned using various techniques. The overall objective of the study is to compare the wealth indices constructed by using weighted and unweighted methods for assessing the socio-economic status of households in rural Bangladesh. Firstly, the study attempts to construct wealth indices based on durable assets using the unweighted method and two techniques of the weighted method: weighted index using the inverse of proportion, and weighted index using principal component analysis (PCA). Following this, the study compares some distributional characteristics of these indices as well as monetary indicators. At the same time, the study evaluates and examines some attractive properties of these indices such as the extent of clumping and truncation, consistency with traditional monetary measures. Comparative analysis revealed that the unweighted asset index, as well as weighted asset index using PCA, can be treated as an efficient alternative to the monetary measures to evaluate the living standard of the households in the present study. However, due to some advantage's asset index using PCA can be considered to be somewhat better than the unweighted index. But, as the unweighted asset index is not very different from the weighted asset index using PCA, it can also be used as an alternative to the monetary measures without the need to use weighting.

6.
Int J Equity Health ; 18(1): 33, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30770739

RESUMO

BACKGROUND: In recent years, developing countries like Bangladesh are facing a higher burden of non-communicable diseases such as hypertension as a result of demographic transition. Prevalence of hypertension is often studied in this setting. However, evidence on undiagnosed hypertension is not widely available in the existing literature. Therefore, the current study focuses on inequalities in the prevalence of undiagnosed hypertension in Bangladesh. METHODS: A total of 8835 participants aged 35+ years were included in this study using nationally representative Bangladesh Demographic and Health Survey 2011 (BDHS). In the survey, systolic blood pressure (SBP) and diastolic blood pressure (DBP) of these participants were measured three times with approximately 10 minutes of an interval between each measurement. Any respondent with either SBP ≥ 140 mmHg or DBP ≥ 90 mmHg was considered as patient with hypertension as per the guidelines from American Heart Association. Among the participants, undiagnosed hypertension was defined as having SBP > =140 mmHg or DBP > =90 mmHg and never taking prescribed medicine or being told by health professionals to lower/control blood pressure. Multiple logistic regression analysis was applied for identifying factors associated with undiagnosed hypertension. Further, socioeconomic inequalities in the prevalence of undiagnosed hypertension were estimated using Concentration Index (C). RESULTS: We found 978 (59.9% of the total) were undiagnosed among 1685 hypertensive patients studied. Regression analysis showed individuals with being underweight, having poor socioeconomic conditions, and lower educational qualifications were more likely to have undiagnosed hypertension. A similar association between undiagnosed hypertension and socioeconomic quintiles was observed using concentration index (C = - 0.07). On the other hand, individuals from higher age group (50-64 or above), female sex, and Sylhet region were at lower risk of undiagnosed hypertension. CONCLUSIONS: This study showed that a large proportion of the cases with hypertension are remained undiagnosed in Bangladesh, especially among the poor and low educated population. Screening and awareness building initiatives on hypertension should be taken for this group of population to reduce the burden of undiagnosed hypertension.


Assuntos
Disparidades nos Níveis de Saúde , Hipertensão/epidemiologia , Adulto , Idoso , Bangladesh/epidemiologia , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência
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