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1.
RSC Adv ; 14(10): 6823-6847, 2024 Feb 21.
Article in English | MEDLINE | ID: mdl-38410361

ABSTRACT

The development of non-noble metal based and cost-effective electrocatalysts for water splitting has attracted significant attention due to their potential in production of clean and green hydrogen fuel. Discovered in 2011, a family of two-dimensional transition metal carbides, nitrides, and carbonitrides, have demonstrated promising performance as electro catalysts in the water splitting process due to their high electrical conductivity, very large surface area and abundant catalytic active sites. However, their-long term stability and recyclability are limited due to restacking and agglomeration of MXene flakes. This problem can be solved by combining MXene with other materials to create their hybrid architectures which have demonstrated higher electrocatalytic performance than pristine MXenes. Electrolysis of water encompasses two half-cell reactions, hydrogen evolution reaction (HER) at the cathode and oxygen evolution reaction (OER) at the anode. Firstly, this concise review explains the mechanism of water splitting. Then it provides an overview of the recent advances about applications of MXenes and their hybrid architectures as HER, OER and bifunctional electrocatalysts for overall water splitting. Finally, the recent challenges and potential outlook in the field have been presented. This concise review may provide further understanding about the role of MXene-based hybrid architectures to develop efficient electrocatalysts for water splitting.

2.
Polymers (Basel) ; 14(22)2022 Nov 09.
Article in English | MEDLINE | ID: mdl-36432957

ABSTRACT

In this study, silica in the form of raw local natural sand was added to high-density-polyethylene (HDPE) in order to develop a composite material in the form of sheets that could have potential applications in thin film industries, such as packaging, or recycling industries, such as in 3D printing. The silica/HDPE composite sheets were developed using a melt extruder followed by using a hot press for compression molding. The impact of two different particle sizes (25 µm and 5 µm) of the silica particles on selected properties such as toughness, elastic modulus, ductility, and composite density were analyzed. A considerable increase in the toughness and elastic modulus was observed from 0 wt% to 20 wt% with a 25 µm filler size. However, a general decreasing trend was observed in the material's toughness and elastic modulus with decreasing particle size. A similar trend was observed for the ductility and the tensile strength of the sheets prepared from both filler particle sizes. In terms of the composite density, as the filler was increased from 20 wt% to 50 wt%, an increase in the composite densities was noticed for both particle sizes. Additionally, the sheets developed with 25 µm particle size had a slightly higher density than the 5 µm particle size, which is expected as the size can account for the higher weight. Results from this work aim to analyze the use of local sand as a filler material that can contribute towards maximizing the potential of such composite materials developed in extrusion industries.

3.
Polymers (Basel) ; 14(16)2022 Aug 17.
Article in English | MEDLINE | ID: mdl-36015609

ABSTRACT

Polymer composite sheets using a low-cost filler (local natural sand) and polymer (high-density polyethylene, HDPE) as a replacement of the traditionally used wood-fiber-based sheets for paper-based applications were developed. The sand/polymer composite sheets were prepared by melt extrusion in a melt blender followed by compression molding. The effects of varying particle size, concentration, and the use of a compatibilizer (polyethylene-grafted maleic anhydride) was studied on the mechano-chemical performance properties of the composite sheets such as morphology, thermal and mechanical properties, and wettability characteristics used in the printing industry. In terms of thermal stability, filler (sand) or compatibilizer addition did not alter the crystallization, melting, or degradation temperatures significantly, thereby promoting good thermal stability of the prepared sheets. Compatibilization improved anti-wetting property with water. Additionally, for the compatibilized sheets prepared from 25 µm sand particles, at 35 wt%, the contact angle with printing ink decreased from 44° to 38.30°, suggesting improved ink-wetting performance. A decrease in the elastic modulus was also observed with the addition of the compatibilizer, with comparable results to commercial stone paper. Results from this study will be considered as a first step towards understanding compatibility of local natural sand and polymers for paper-based application.

4.
RSC Adv ; 12(8): 4624-4634, 2022 Feb 03.
Article in English | MEDLINE | ID: mdl-35425492

ABSTRACT

Owing to the tremendous energy storage capacity of two-dimensional transition metal carbides (MXenes), they have been efficiently utilized as a promising candidate in the field of super-capacitors. The energy storage capacity of MXenes can be further enhanced using metal dopants. Herein, we have reported the synthesis of pristine and nickel doped niobium-carbide (Nb2C) MXenes, their computational and electrochemical properties. Upon introduction of nickel (Ni) the TDOS increases and a continuous DOS pattern is observed which indicates coupling between Ni and pristine MXene. The alterations in the DOS, predominantly in the nearby region of the Fermi level are profitable for our electrochemical applications. Additionally, the Ni-doped sample shows a significant capacitive performance of 666.67 F g-1 which can be attributed to the additional active sites generated by doping with Ni. It is worth noting that doped MXenes exhibited a capacitance retention of 81% up to 10 000 cycles. The current study unveils the opportunities of using MXenes with different metal dopants and hypothesize on their performance for energy storage devices.

5.
Polymers (Basel) ; 14(6)2022 Mar 12.
Article in English | MEDLINE | ID: mdl-35335474

ABSTRACT

In this work, the effect of alkaline treatment on the thermal insulation and mechanical properties of date palm wood fibers (DPWF) and polylactic acid (PLA) green composite was studied. Alkaline treatment was applied to DPWF using two different solutions: sodium hydroxide (NaOH) and potassium hydroxide (KOH), with concentration of 2 vol.%. The fibers were later incorporated into PLA with weight percentages from 10 to 40 wt.%, to form three composite types: PLA with untreated fibers (PLA-UTDPWF), PLA with KOH treated fibers (PLA-KOH), and PLA with NaOH treated fibers (PLA-NaOH). The prepared composites were for use as a green thermal insulation material. The composites were tested to assess the effect of treatment on their physical (density and degree of crystallization), thermal (thermal conductivity, specific heat capacity, thermal diffusivity, thermal degradation, glass transition, and melting temperature), and mechanical properties. Moreover, the composite structural characteristics were investigated using FTIR and SEM analysis. The alkaline treatment significantly increased the crystallinity of the composites, specifically for higher filler loadings of 30 and 40 wt.%. The crystallinity for the 40 wt.% increased from 33.2% for PLA-UTDPWF, to 41% and 51%, for PLA-NaOH and PLA-KOH, respectively. Moreover, the alkaline treatment reduced the density and produced lighter composites than the untreated specimens. For instance, the density of 40 wt.% composite was reduced from 1.43, to 1.22 and 1.30 gcm3 for PLA-NaOH and PLA-KOH, respectively.

6.
J Pharm Bioallied Sci ; 13(1): 123-128, 2021.
Article in English | MEDLINE | ID: mdl-34084058

ABSTRACT

OBJECTIVE: The objective of the study was to evaluate the knowledge, attitude, and practice among pre-final and final year students of pharmacy, medicine, biotechnology, and business faculties about oral hygiene. MATERIALS AND METHODS: A cross-sectional observational study was conducted to evaluate the knowledge, attitude, and practice of students towards oral hygiene at a private university in Malaysia. Validated questionnaires were distributed to a convenient stratified sample of 324 students studying in the different selected faculties, namely pharmacy, medicine, biotechnology, and business, respectively. The Statistical Package for Social Science (SPSS) Version 24.0 was used to analyze the data. RESULTS: With regard to knowledge, upon evaluation, it was seen that the students of the Faculty of Pharmacy had the highest percentage of adequate knowledge, which was statistically significant with a P-value of 0.001 and the effect size of 0.246. On the evaluation of attitudes, it was seen that the Faculty of Biotechnology had the highest positive attitudes. According to race, Malay students had the highest positive attitude among all the races that participated in the study, which showed a P-value of 0.037 with the effect size of 0.034. Regarding practice, the Faculty of Pharmacy had the lowest practice compared with the other faculties. This variable had a P-value of 0.001 and showed to have significance against the practice with an effect size of 0.193. CONCLUSION: Overall, a good attitude was seen amongst the students on their oral hygiene. It was also observed that the attitude, knowledge, and practice of the students in a private university increased with an increasing level of education.

7.
Polymers (Basel) ; 12(9)2020 Sep 14.
Article in English | MEDLINE | ID: mdl-32938000

ABSTRACT

This work aims to provide an extensive evaluation on the use of polylactic acid (PLA) as a green, biodegradable thermal insulation material. The PLA was processed by melt extrusion followed by compression molding and then subjected to different annealing conditions. Afterwards, the thermal insulation properties and structural capacity of the PLA were characterized. Increasing the annealing time of PLA in the range of 0-24 h led to a considerable increase in the degree of crystallization, which had a direct impact on the thermal conductivity, density, and glass transition temperature. The thermal conductivity of PLA increased from 0.0643 W/(m·K) for quickly-cooled samples to 0.0904 W/(m·K) for the samples annealed for 24 h, while the glass transition temperature increased by approximately 11.33% to reach 59.0 °C. Moreover, the annealing process substantially improved the compressive strength and rigidity of the PLA and reduced its ductility. The results revealed that annealing PLA for 1-3 h at 90 °C produces an optimum thermal insulation material. The low thermal conductivity (0.0798-0.0865 W/(m·K)), low density (~1233 kg/m3), very low water retention (<0.19%) and high compressive strength (97.2-98.7 MPa) in this annealing time range are very promising to introduce PLA as a green insulation material.

8.
J Pharm Bioallied Sci ; 12(1): 57-63, 2020.
Article in English | MEDLINE | ID: mdl-32801601

ABSTRACT

PURPOSE: The demand of complementary and alternative medicine (CAM) has increased drastically over the past few decades. The perceptions about CAMs among general population are positive. However, the literature highlights that effectiveness and acceptance of alternative therapies among the general population is still a subject of debate. MATERIALS AND METHODS: This is a cross-sectional study and the response along with demographic details was collected through a validated questionnaire; the results were analyzed by using a validated data collection tool. The results were concluded based on good, moderate, and poor responses, which were evaluated through data analysis by using the Statistical Package for the Social Sciences software version 20.0., SPSS Inc., Chicago, III, USA. A value of P < 0.05 was considered statistically significant. RESULTS: In total, 182 (44.4%) of male and 228 (55.6%) of female respondents were selected for this study. Studies showed that a greater knowledge level was observed among female respondents (15.55 ± 2.7, P < 0.001). The selected Chinese population had relatively good knowledge (i.e., 15.63, P = 0.006). People practicing Buddhism had also good knowledge. Rural population had lesser family income and showed a good practice pattern and understanding (P = 0.006). The positive attitude was identified among women ( P < 0.001) with a mean score of 15.55 ± 2.7. Postgraduate participants were found to have diverse results with SD ± 6.23, and 77.1% had a good attitude. A statistically significant association was observed between religion and attitude of respondents (P < 0.001). CONCLUSION: Although a better practice was noticed in Malaysian population, more awareness is required and knowledge should be disseminated among the population to improve the overall health and quality of life in Malaysia.

9.
Heliyon ; 6(3): e03589, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32195403

ABSTRACT

The crystallization behavior of polyethylene/thermally reduced graphene (PE/TRG) nanocomposites prepared via solvent blending is investigated using a differential scanning calorimeter, and results are compared with PE/carbon black (CB) composites. The effects of TRG and CB concentrations on the crystallization process are studied under isothermal and dynamic conditions. The Avrami and modified Avrami equations provided excellent fits to isothermal and dynamic crystallization kinetics data, respectively. The TRG nanosheets acted as nucleating agents during crystallization attributed to substantial decrease in crystallization half time at higher TRG concentrations. The reduced surface energy of the nanocomposites with incorporation of TRG further confirmed its nucleating behavior.

10.
ACS Omega ; 4(24): 20530-20539, 2019 Dec 10.
Article in English | MEDLINE | ID: mdl-31858037

ABSTRACT

The current environmental and potable water crisis requires technological advancement to tackle the issues caused by different organic pollutants. Herein, we report the degradation of organic pollutants such as Congo Red and acetophenone from aqueous media using visible light irradiation. To harvest the solar energy for photocatalysis, we fabricated a nanohybrid system composed of bismuth ferrite nanoparticles with two-dimensional (2D) MXene sheets, namely, the BiFeO3 (BFO)/Ti3C2 (MXene) nanohybrid, for enhanced photocatalytic activity. The hybrid BFO/MXene is fabricated using a simple and low-cost double-solvent solvothermal method. The SEM and TEM images showed that the BFO nanoparticles are attached onto the surface of 2D MXene sheets. The photocatalytic degradation achieved by the hybrid is found to be 100% in 42 min for the organic dye (Congo Red) and 100% for the colorless aqueous pollutant (acetophenone) in 150 min. The BFO/MXene hybrid system exhibited a large surface area of 147 m2 g-1 measured via the Brunauer-Emmett-Teller sorption-desorption technique, which is found to be the largest among all BFO nanoparticles and derivatives. The photoluminescence spectra indicate a low electron-hole recombination rate. Fast and efficient degradation of organic molecules is caused by two factors: larger surface area and lower electron-hole recombination rate, which makes the BFO/MXene nanohybrid a highly efficient photocatalyst and a promising candidate for many future applications.

11.
J Pharm Bioallied Sci ; 11(4): 299-309, 2019.
Article in English | MEDLINE | ID: mdl-31619911

ABSTRACT

A strict and adherence treatment is required by the patient with diabetes mellitus and it demands a proper self-medication by the patient. Pharmacists are involved in providing self-management support to the patients. This review evaluates the interventions of pharmacist for patients to improve self-management with diabetes mellitus and also to improve the clinical outcomes of diabetes mellitus. A comprehensive literature search was performed by using different keywords "pharmacist-led intervention," "diabetes," "effect of pharmacist on outcome of diabetes," and "self-management of diabetes" with the help of various electronic databases such as PubMed, Science Direct, Embase, Web of Science, and the Cochrane Library from the beginning of the database through September 2018. The primary outcome was glycated hemoglobin (HbA1c), whereas the secondary outcomes were blood glucose level, blood pressure (BP) measure, body mass index, lipids, adherence to medication, and quality of life. Twenty-five studies comprising 2997 diabetic patients were included in the analysis. Pharmacist-led intervention was involved in all included studies in the form of education on diabetes and its complications, medication adherence, lifestyle, and education about self-management skills. Pharmacist-led interventions are able to reduce HbA1c levels with a mean of 0.75%. Most studies do not expose the material and methods used in pharmacist-led intervention. The variation in the reduction of HbA1c, fasting blood sugar, BP, and lipid profile was due to the lack of this standardization. The included studies indicated that pharmacist-led interventions in diabetes mellitus can significantly improve the outcomes of diabetes mellitus and its complication later on. Hence, these long-term improvements in outcomes added more value of pharmacists in health-care system of the world.

12.
ACS Omega ; 4(5): 8661-8668, 2019 May 31.
Article in English | MEDLINE | ID: mdl-31459955

ABSTRACT

Over the years, scarcity of fresh potable water has increased the demand for clean water. Meanwhile, with the advent of nanotechnology, the use of nanomaterials for photocatalytic degradation of pollutants in wastewaters has increased. Herein, a new type of nanohybrids of La- and Mn-codoped bismuth ferrite (BFO) nanoparticles embedded into transition-metal carbide sheets (MXene-Ti3C2) were prepared by a low-cost double-solvent sol-gel method and investigated for their catalytic activity in dark and photoinduced conditions. The photoluminescence results showed that pure BFO has the highest electron hole recombination rate as compared to all the codoped BFO/Ti3C2 nanohybrids. The higher electron-hole pair generation rate of the nanohybrids provides a suitable environment for fast degradation of organic dye molecules. The band gap of the prepared nanohybrid was tuned to 1.73 eV. Moreover, the BLFO/Ti3C2 and BLFMO-5/Ti3C2 degraded 92 and 93% of the organic pollutant, respectively, from water in dark and remaining in the light spectrum. Therefore, these synthesized nanohybrids could be a promising candidate for catalytic and photocatalytic applications in future.

13.
J Taibah Univ Med Sci ; 13(6): 552-556, 2018 Dec.
Article in English | MEDLINE | ID: mdl-31435377

ABSTRACT

OBJECTIVES: Faculty development plays a pivotal role in developing competent and effective teachers. The eventual goal of faculty development is to transfer newly acquired knowledge, skills, and attitudes to the workplace to positively influence students' learning. However, the transfer of training skills is a complex phenomenon, and not much has been reported about the factors affecting this process, especially in the health sciences. This study aims to explore the factors hindering or aiding the transfer of training (newly learned competencies) to the workplace. METHODS: This cross-sectional qualitative study employed a purposive sampling technique and incorporated seven programme developers. The data were collected through semi-structured interviews, and then analysed using thematic analysis. RESULTS: The interviews with programme developers and faculty trainers revealed that the transfer of training to educational practices is a complex and multidimensional process. Primarily, such transfer is influenced by many variables that can be broadly categorised into three groups: trainee characteristics, training design features, and environmental factors. CONCLUSION: The current study has implications for understanding learning transfer after a faculty development programme. It provides a brief overview of the individual, programmatic, and environmental factors that influence the transfer of training to an educational setup.

14.
Environ Sci Pollut Res Int ; 20(5): 3271-9, 2013 May.
Article in English | MEDLINE | ID: mdl-23093418

ABSTRACT

In this article, we study the use of thermally reduced graphene (TRG) for oil spill cleanup. TRG was synthesized by thermal exfoliation of graphite oxide and characterized by X-ray diffusion, Raman spectroscopy, SEM, TEM, elemental analysis, and Brunauer-Emmett-Teller (BET) surface area measurement. Various aspects of the sorption process have been studied including the sorption capacity, the recovery of the adsorbed oil, and the recyclability of TRG. Our results shows that TRG has a higher sorption capacity than any other carbon-based sorbents, with sorption capacity as high as 131 g of oil per gram TRG. With recovery of the sorbed oil via filtration and reuse of TRG for up to six cycles, 1 g of TRG collectively removes approximately 300 g of crude oil. Moreover, the effects of TRG bulk density, pore volume, and carbon/oxygen ratio and the oil viscosity on the sorption process are also discussed.


Subject(s)
Environmental Restoration and Remediation/methods , Graphite/chemistry , Petroleum Pollution/prevention & control , Water Pollutants, Chemical/chemistry , Adsorption , Carbon/chemistry , Hydrophobic and Hydrophilic Interactions , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Oxygen/chemistry , Spectrum Analysis, Raman , Viscosity
15.
Addiction ; 99(10): 1306-14, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15369569

ABSTRACT

AIMS: To compare the prevalence of personality disorder in alcohol and drug populations with special attention to its impact on psychopathology and service characteristics. DESIGN: Cross-sectional survey. SETTING: Three alcohol and four drug services in four urban UK centres. PARTICIPANTS: Two hundred and sixteen drug and 64 alcohol service patients randomly sampled from current treatment populations. MEASUREMENTS: A treatment population census recorded demographic and diagnostic data. Patient interviews assessed the presence, cluster type and severity of personality disorder using the Quick Personality Assessment Schedule (PAS-Q). Other psychopathology was measured using the Comprehensive Psychopathological Rating Scale (CPRS). A case-note audit recorded psychotic psychopathology using the OPCRIT schedule and data regarding social morbidity. FINDINGS: The overall prevalence of personality disorder was 37% in the drug service sample and 53% in the alcohol service sample. The distribution of severity and clusters differed markedly between the two samples. There was a significant association between the severity of personality disorder and psychopathology in both samples. Levels of morbidity associated with clusters B and C were similar. Clinical diagnosis of personality disorder showed high specificity but low sensitivity when compared to PAS-Q. CONCLUSIONS: In both alcohol and drug service populations, personality disorder is associated with significantly increased rates of psychopathology and social morbidity that worsens with increasing severity of the disorder. Despite this, personality disorder is poorly identified by clinical staff. The PAS-Q may be useful as a clinical assessment tool in the substance misuse population for the early identification and management of patients with personality disorder.


Subject(s)
Personality Disorders/epidemiology , Substance-Related Disorders/epidemiology , Comorbidity , Cross-Sectional Studies , Data Collection , Humans , Patient Compliance , Personality Disorders/etiology , Prevalence , Psychiatric Status Rating Scales , Substance-Related Disorders/complications , United Kingdom/epidemiology
16.
Addict Biol ; 7(3): 269-77, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12126485

ABSTRACT

Many reviews describe the effectiveness of methadone treatment in reducing illicit drug use and associated behaviours among opiate misusers. The strongest evidence includes social outcomes such as reduced debt and crime, and relates overwhelmingly to maintenance rather than detoxification treatment. Drug clinics are often dominated by individuals unable to withdraw fully from methadone, while the "harm reduction" model accepts some ongoing drug use, with attendant risks. Security measures are necessary to avoid abuse of treatments, but these may be undermined by the agenda of "partnerships with patients" in decision-making. Buprenorphine appears both safer and less addictive than methadone, and lofexidine is effective as a non-substitute detoxification method. Naltrexone can clearly reduce relapse rates, provided consumption is assured, while for individuals unable to detoxify or avoid euphoriant opiates, morphine and diamorphine are sometimes used. In non-opiate misuse, clinical studies of a wide range of medications have produced relatively few positive findings.


Subject(s)
Methadone/administration & dosage , Narcotic Antagonists/administration & dosage , Narcotics/administration & dosage , Opioid-Related Disorders/rehabilitation , Drug Prescriptions , Euphoria/drug effects , Humans , Methadone/adverse effects , Narcotic Antagonists/adverse effects , Narcotics/adverse effects , Opioid-Related Disorders/prevention & control , Opioid-Related Disorders/psychology , Patient Compliance/psychology , Risk Factors
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