Herein, a robust microporous aluminum tetracarboxylate framework, MIL-120(Al)-AP, (MIL, AP: Institute Lavoisier and Ambient Pressure synthesis, respectively) is reported, which exhibits high CO uptake (1.9 mmol g at 0.1 bar, 298 K).
View Article and Find Full Text PDFOwing to their high porosity and tunability, porous solids such as metal-organic frameworks (MOFs), zeolites, or activated carbons (ACs) are of great interest in the fields of air purification, gas separation, and catalysis, among others. Nonetheless, these materials are usually synthetized as powders and need to be shaped in a more practical way that does not modify their intrinsic property (i.e.
View Article and Find Full Text PDFMetal-Organic Frameworks (MOFs) with open metal sites (OMS) interact strongly with a range of polar gases/vapors. However, under ambient conditions, their selective adsorption is generally impaired due to a high OMS affinity to water. This led previously to the privilege selection of hydrophobic MOFs for the selective capture/detection of volatile organic compounds (VOCs).
View Article and Find Full Text PDFVolatile organic compounds (VOCs) such as benzene, toluene, ethylbenzene and xylene (BTEX) are air pollutants that harm human health. This study aims to identify BTEX concentrations before the lockdown known as the Movement Control Order was imposed (BMCO), during the implementation of the Movement Control Order (MCO), and then during the Conditional Movement Control Order (CMCO). These orders were introduced during the COVID-19 pandemic in Malaysia.
View Article and Find Full Text PDFThis study aims to determine the trends of volatile organic compound (VOC) concentrations and their potential contribution to O formation. The hourly data (August 2017 to July 2018) for 29 VOCs were obtained from three Malaysian Department of Environment continuous air quality monitoring stations with different urban backgrounds (Shah Alam, Cheras, Seremban). The Ozone Formation Potential (OFP) was calculated based on the individual Maximum Incremental Reactivity (MIR) and VOC concentrations.
View Article and Find Full Text PDFPreserving culture heritage cellulose acetate-based historical films is a challenge due to the long-term instability of these complex materials and a lack of prediction models that can guide conservation strategies for each particular film. In this work, a cellulose acetate degradation model is proposed as the basis for the selection of appropriate strategies for storage and conservation for each specimen, considering its specific information. Due to the formulation complexity and diversity of cellulose acetate-based films produced over the decades, we hereby propose a hybrid modeling approach to describe the films degradation process.
View Article and Find Full Text PDFA deep understanding of the degradation of cellulose diacetate (CDA) polymer is crucial in finding the appropriate long-term stability solution. This work presents an investigation of the reaction mechanism of hydrolysis using electronic density functional theory calculations with the B3LYP/6-31++G** level of theory to determine the energetics of the degradation reactions. This information was coupled with the transition-state theory to establish the kinetics of degradation for both the acid-catalyzed and noncatalyzed degradation pathways.
View Article and Find Full Text PDFACS Appl Mater Interfaces
March 2021
Temperature characterization and quantification at the nanoscale remain core challenges in applications based on photoinduced heating of nanoparticles. Here, we propose a new approach to obtain quantitative temperature measurements on individual nanoparticles by combining modulated photothermal stimulation and heterodyne digital holography. From full-field reconstructed holograms, the temperature is determined with a precision of 0.
View Article and Find Full Text PDFThe COVID-19 pandemic forced many governments across the world to implement some form of lockdown to minimalize the spread of the virus. On 18th March 2020, the Malaysian government put into action an enforced movement control order (MCO) to reduce the numbers of infections. This study aims to investigate the concentrations of air pollutants during the MCO in the Klang Valley.
View Article and Find Full Text PDF: Elastomeric infusion pumps are widely used in the delivery of parenteral medications in the home, but real-life conditions may not match calibration or standardised testing conditions. This study investigated the impact of changes in infusion pump height and/or back pressure on infusion pump function. : Volume delivered after one day, infusion duration, average and peak flow rates and time spent within stated accuracy were determined for four elastomeric and one electronic pump using gravimetric technique.
View Article and Find Full Text PDFObjective: To use relationships between tightening parameters, related to bone quality, to develop an automated system that determines and controls the level of screw tightening.
Methods: An algorithm relating current at head contact (IHC) to current at construct failure (Imax) was developed. The algorithm was used to trigger cessation of screw insertion at a predefined tightening level, in real time, between head contact and maximum current.
We have investigated the effective dielectric response of a subwavelength grating made of highly doped semiconductors (HDS) excited in reflection, using numerical simulations and spectroscopic measurement. The studied system can exhibit strong localized surface resonances and has, therefore, a great potential for surface-enhanced infrared absorption (SEIRA) spectroscopy application. It consists of a highly doped InAsSb grating deposited on lattice-matched GaSb.
View Article and Find Full Text PDFAnterior Gradient-2 (AGR2) is a component of a pro-oncogenic signalling pathway that can promote p53 inhibition, metastatic cell migration, limb regeneration, and cancer drug-resistance. AGR2 is in the protein-disulphide isomerase superfamily containing a single cysteine (Cys-81) that forms covalent adducts with its client proteins. We have found that mutation of Cysteine-81 attenuates its biochemical activity in its sequence-specific peptide docking function, reduces binding to Reptin, and reduces its stability in cells.
View Article and Find Full Text PDFTime-elapsed analysis of bone is an innovative technique that uses sequential image data to analyze bone mechanics under a given loading regime. This paper presents the development of a novel device capable of performing step-wise screw insertion into excised bone specimens, within the microCT environment, whilst simultaneously recording insertion torque, compression under the screw head and rotation angle. The system is computer controlled and screw insertion is performed in incremental steps of insertion torque.
View Article and Find Full Text PDFJ Orthop Trauma
November 2015
Objective: The level to which bone screws are tightened is determined subjectively by the operating surgeon. It is likely that the tactile feedback that surgeons rely on is based on localized tissue yielding, which may predispose the screw-bone interface to failure. A limited number of studies have investigated the ratio between clinical tightening torque and stripping torque.
View Article and Find Full Text PDFUsing magnetic tunnelling junction sensors, a novel magnetometer probe for the identification of the sentinel lymph node using magnetic tracers was developed. Probe performance was characterised in vitro and validated in a preclinical swine model. Compared to conventional gamma probes, the magnetometer probe showed excellent spatial resolution of 4.
View Article and Find Full Text PDFProteins targeted to secretory pathway enter the endoplasmic reticulum where they undergo post-translational modification and subsequent quality control executed by exquisite catalysts of protein folding, protein disulphide isomerases (PDIs). These enzymes can often provide strict conformational protein folding solutions to highly cysteine-rich cargo as they facilitate disulphide rearrangement in the endoplasmic reticulum. Under conditions when PDI substrates are not isomerised properly, secreted proteins can accumulate in the endoplasmic reticulum leading to endoplasmic reticulum stress initiation with implications for human disease development.
View Article and Find Full Text PDFA generalized lock-in detection method is proposed to extract amplitude and phase from optical interferometers when an arbitrary periodic phase or frequency modulation is used. The actual modulation function is used to create the reference signals providing an optimal extraction of the useful information, notably for sinusoidal phase modulation. This simple and efficient approach has been tested and applied to phase sensitive spectroscopy and near-field optical measurements.
View Article and Find Full Text PDFPurpose: Seizure related unconscious face-down positioning could contribute to sudden unexpected death in epilepsy via asphyxia. Low airflow resistance lattice foam pillows have been advocated for this group. However, data to support this approach remain lacking, and low airflow resistance per se may not negate asphyxia risk from expired gas rebreathing.
View Article and Find Full Text PDFVision-impaired individuals often use a long white cane to assist them with gathering information about their surroundings. However, these aids are generally not used to detect obstacles above knee height. The purpose of this study is to determine whether a low-cost, custom-built electronic device clipped onto a traditional cane can provide adequate vibratory warning to the user of obstacles above knee height.
View Article and Find Full Text PDFInternal fixation of fractures often requires the tightening of bone screws to stabilise fragments. Inadequate application of torque can leave the fracture unstable, while over-tightening results in the stripping of the thread and loss of fixation. The optimal amount of screw torque is specific to each application and in practice is difficult to attain due to the wide variability in bone properties including bone density.
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