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1.
Small ; 20(30): e2400828, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38693068

ABSTRACT

Efficient support materials are crucial for maximizing the efficacy of nanomaterials in various applications such as energy storage, drug delivery, catalysis, and environmental remediation. However, traditional supports often hinder nanomaterial performance due to their high weight ratio and limited manageability, leading to issues like tube blocking and secondary pollution. To address this, a novel grapefruit-inspired polymeric capsule (GPC) as a promising carrier platform is introduced. The millimeter-scale GPC features a hydrophilic shell and an internal hierarchical microstructure with 80% void volume, providing ample space for encapsulating diverse nanomaterials including metals, polymers, metal-organic frameworks, and silica. Through liquid-phase bottom-up methods, it is successfully loaded Fe2O3, SiO2, polyacrylic acid, and Prussian blue nanomaterials onto the GPC, achieving high mass ratio (1776, 488, 898, and 634 wt.%, respectively). The GPC shell prevents nanomaterial leakage and the influx of suspended solids, while its internal framework enhances structural stability and mass transfer rates. With long-term storage stability, high carrying capacity, and versatile applicability, the GPC significantly enhances the field applicability of nanomaterials.

2.
Mikrochim Acta ; 188(4): 132, 2021 03 20.
Article in English | MEDLINE | ID: mdl-33745002

ABSTRACT

Concave gold nanocubes are viable optical nanoprobes for the determination of nitrite ions. Herein, a novel approach was developed, based on the measurement of localized surface plasmon resonance absorption. The addition of nitrite ions selectively induced the etching of concave gold nanocubes, abrading the sharp vertices to spherical corners, which resulted in blue-shifted absorption accompanied by a color change from sapphire blue to light violet. The mechanism of selective etching of concave gold nanocube tips was elucidated by using X-ray photoelectron spectroscopy and atom probe tomography. The optimized detection of NO2- via the concave gold nanocube-based probe occurred at pH 3.0 and in 20 mM NaCl concentration at 40 °C. The absorption ratios (A550 nm/A640 nm) were proportional to the NO2- concentrations in the range 0.0-30 µM, with a detection limit of 38 nM (limit of quantitation of 0.12 µM and precision of 2.7%) in tap water. The highly selective and sensitive colorimetric assay has been successfully applied to monitor the nitrite ion concentrations in spiked tap water, pond water, commercial ham, and sausage samples.


Subject(s)
Colorimetry/methods , Metal Nanoparticles/chemistry , Nitrites/analysis , Animals , Drinking Water/analysis , Food Contamination/analysis , Gold/chemistry , Limit of Detection , Ponds/analysis , Pork Meat/analysis , Surface Plasmon Resonance , Swine , Water Pollutants, Chemical/analysis
3.
Nanotechnology ; 31(42): 425604, 2020 Jun 08.
Article in English | MEDLINE | ID: mdl-32512542

ABSTRACT

The synthesis of boron nitride nanodisks (BNNDs) with reducing the size and having fewer disk layers, and low optical band gap (E g) is essential for practical applications in electronics and optoelectronic devices. So far, the large-scale preparation of hydroxyl (-OH) and hydroperoxyl (-OOH) functionalized boron nitride nanosheets and BNNDs with reduced E g is still a challenge. This research demonstrates the scalable and solution process synthesis of hydroxyl (-OH) and hydroperoxyl (-OOH) functionalization of BNNDs at the edges and basal planes from pristine hexagonal boron nitride (h-BN) by the combination of modified Hummer's method and Fenton's chemistry. Modified Hummer's method induces exfoliation and cutting of the h-BN into BNNDs with a low percentage of -OH functionalization (6.90%), which is further exfoliated and cut by Fenton's reagent with improved -OH and -OOH functionalization (ca. 17.25%). The combination of these two methods allows us to reduce the size of the OH/OOH-BNNDs to ca. 200 nm with the number of disk layers in the range from ca. 6-11. Concurrently, the E g of h-BN was decreased from ca. 5.10 to ca. 3.58 eV for OH/OOH-BNNDs, which enables the possible application of OH/OOH-BNNDs in semiconductor electronics. The high percentage of -OH and -OOH functionalizations in the OH/OOH-BNNDs enablesg them to disperse in various solvents with high long-term stability.

4.
Sensors (Basel) ; 20(3)2020 Jan 22.
Article in English | MEDLINE | ID: mdl-31979160

ABSTRACT

This research demonstrated the development of a simple, cost-effective, and label-free immunosensor for the detection of α-synuclein (α-Syn) based on a cystamine (CYS) self-assembled monolayer (SAM) decorated fluorine-doped tin oxide (FTO) electrode. CYS-SAM was formed onto the FTO electrode by the adsorption of CYS molecules through the head sulfur groups. The free amine (-NH2) groups at the tail of the CYS-SAM enabled the immobilization of anti-α-Syn-antibody, which concurrently allowed the formation of immunocomplex by covalent bonding with α-Syn-antigen. The variation of the concentrations of the attached α-Syn at the immunosensor probe induced the alternation of the current and the charge transfer resistance (Rct) for the redox response of [Fe(CN)6]3-/4-, which displayed a linear dynamic range from 10 to 1000 ng/mL with a low detection limit (S/N = 3) of ca. 3.62 and 1.13 ng/mL in differential pulse voltammetry (DPV) and electrochemical impedance spectra (EIS) measurements, respectively. The immunosensor displayed good reproducibility, anti-interference ability, and good recoveries of α-Syn detection in diluted human serum samples. The proposed immunosensor is a promising platform to detect α-Syn for the early diagnose of Parkinson's disease, which can be extended for the determination of other biologically important biomarkers.


Subject(s)
Biosensing Techniques/methods , Electrochemical Techniques/methods , Electrodes , Cystamine/chemistry , alpha-Synuclein/analysis
5.
J Nanosci Nanotechnol ; 19(3): 1562-1566, 2019 03 01.
Article in English | MEDLINE | ID: mdl-30469223

ABSTRACT

Polymer containing isatin was synthesized by super acid-catalyzed carbon-carbon coupling reaction. Propylsulfonic acid was grafted on isatin unit by substitution reaction with potassium salt of 3-bromo-1-propanesulfonic acid. The sulfonic acid composition was regulated at 25~80 mol% of propylsulfonic acid in order to achieve expected ion exchange capacity of maximum 2.0 meq/g. The copolymers were of high molecular weight (inherent viscosity, ηinh = 1.2 dL/g) to afford a tough membrane by solution casting. Composite membranes were prepared by sulfonated polymer and SiO2 nanoparticles (20 nm, 4~10% wt). All these composite membranes were casted from the solution of sulfonated polymer in dimethylsulfoxide (DMSO) to afford 25 µm. The structural properties of the synthesized polymers were investigated by 1H NMR spectroscopy. The membranes were studied by ion exchange capacity (IEC), water uptake, dimensional stability and proton conductivity assessment by comparing with Nafion®. As increasing the IEC values, the small hydrophobic components induced high proton conductivities and proton diffusion coefficients. These kinds of membranes without ether linkages showed low water swelling as well.

6.
Nat Commun ; 15(1): 3889, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38719796

ABSTRACT

There is a growing demand for adsorption technologies for recovering and recycling precious metals (PMs) in various industries. Unfortunately, amine-functionalized polymers widely used as metal adsorbents are ineffective at recovering PMs owing to their unsatisfactory PM adsorption performance. Herein, a star-shaped, hydrazide-functionalized polymer (S-PAcH) is proposed as a readily recoverable standalone adsorbent with high PM adsorption performance. The compact chain structure of S-PAcH containing numerous hydrazide groups with strong reducibility promotes PM adsorption by enhancing PM reduction while forming large, collectable precipitates. Compared with previously reported PM adsorbents, commercial amine polymers, and reducing agents, S-PAcH exhibited significantly higher adsorption capacity, selectivity, and kinetics toward three PMs (gold, palladium, and platinum) with model, simulated, and real-world feed solutions. The superior PM recovery performance of S-PAcH was attributed to its strong reduction capability combined with its chemisorption mechanism. Moreover, PM-adsorbed S-PAcH could be refined into high-purity PMs via calcination, directly utilized (upcycled) as catalysts for dye reduction, or regenerated for reuse, demonstrating its high practical feasibility. Our proposed PM adsorbents would have a tremendous impact on various industrial sectors from the perspectives of environmental protection and sustainable development.

7.
Small ; 9(2): 284-93, 2013 Jan 28.
Article in English | MEDLINE | ID: mdl-22930531

ABSTRACT

Self-assembled nanoaggregates co-encapsulating doxorubicin (DOX) and oligonucleotide are prepared for dual-responsive breakdown of the nanostructure with complete disappearance characteristics. Four-arm poly(ethylene glycol) is co-conjugated with DOX and anti-bcl-2 oligonucleotide with reducible linkers and acid-cleavable linkers, respectively. The conjugate is hydrophobically self-assembled into nanoaggregates in aqueous solution. Elemental scanning of the nanoaggregates reveals their core-shell structure with DOX and oligonucleotide located at the core and the shell, respectively. The tracking of size modulation suggests the complete disappearance of the particles under reducing conditions and the liberation of oligonucleotide at low pH, which is confirmed by dynamic light scattering and electron microscopy. The release of DOX and oligonucleotide is controlled by the pH and the reducing potential of the medium, and most of the drug and DNA are released in 24 h. The released fractions are analyzed by reversed-phase chromatography, which indicates facile cleavage of DOX and oligonucleotide from the carriers. The nanoaggregates with both DOX and oligonucleotide show the lowest IC(50) value when a cytotoxicity assay is performed against A549 cells. Apoptosis assay also confirms that cells treated with the nanoaggregates having both DOX and oligonucleotide show higher fluorescence intensity of antiapoptotic antibody than native DOX.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Doxorubicin/pharmacology , Nanostructures , Antineoplastic Agents/administration & dosage , Chromatography, High Pressure Liquid , Dose-Response Relationship, Drug , Doxorubicin/administration & dosage , Humans , Hydrogen-Ion Concentration
8.
Water Res ; 244: 120543, 2023 Oct 01.
Article in English | MEDLINE | ID: mdl-37659178

ABSTRACT

The accumulation of plastic debris in aquatic organisms has raised serious concerns about the potential health implications of their incorporation into the food chain. However, conventional water remediation techniques are incapable of effectively removing nanoplastics (NPs) smaller than 200 nm, which can have harmful effect on animal and human health. Herein, we demonstrate the "on-the-fly" capture of NPs through their enlargement (approximately 4,100 times) using self-propelled nanobots composed of a metal-organic framework. Under visible-light irradiation, the iron hexacyanoferrate (FeHCF) nanobot exhibits fuel-free motion by electrostatically adsorbing NPs. This strategy can contribute to reducing plastic pollution in the environment, which is a significant environmental challenge. Light-induced intervalence charge transfer in the FeHCF nanobot lattice induces bipolarity on the nanobot surface, leading to the binding of negatively charged NPs. The local electron density in the lattice then triggers self-propulsion, thereby inducing agglomeration of FeHCF@NP complexes to stabilize their metastable state. The FeHCF nanobot exhibits a maximum removal capacity of 3,060 mg∙g-1 and rate constant of 0.69 min-1, which are higher than those recorded for materials reported in the literature.


Subject(s)
Microplastics , Water Pollutants, Chemical , Animals , Humans , Water Pollutants, Chemical/analysis , Light , Environmental Pollution , Water
9.
RSC Adv ; 13(47): 33028-33037, 2023 Nov 07.
Article in English | MEDLINE | ID: mdl-38025876

ABSTRACT

A gold nanourchin (AuNU) probe with a novel sensing mechanism for monitoring H2S was developed as a feasible colorimetric sensor. In this study, AuNUs that are selectively responsive to H2S were fabricated in the presence of trisodium citrate and 1,4-hydroquinone using a seed-mediated approach. Upon exposure of the AuNU solution to H2S, the hydrosulfide ions (HS-) in the solution are converted into oligomeric sulfides by 1,4-hydroquinone used as a reducing agent during the synthesis of AuNUs. The oligomeric sulfides formed in the AuNU solution upon the addition of H2S were found to coat the surface of the AuNUs, introducing a blue shift in absorption accompanied by a color change in the solution from sky blue to light green. This colorimetric alteration by the capping of oligomeric sulfides on the surface of AuNUs is unique compared to well-known color change mechanisms, such as aggregation, etching, or growth of nanoparticles. The novel H2S sensing mechanism of the AuNUs was characterized using UV-Vis spectroscopy, high-resolution transmission microscopy, X-ray photoelectron spectroscopy, surface-enhanced Raman spectroscopy, secondary ion mass spectroscopy, liquid chromatography-tandem mass spectrometry, and atom probe tomography. H2S was reliably monitored with two calibration curves comprising two sections with different slopes according to the low (0.3-15 µM) and high (15.0-300 µM) concentration range using the optimized AuNU probe, and a detection limit of 0.29 µM was obtained in tap water.

10.
Membranes (Basel) ; 12(3)2022 Mar 16.
Article in English | MEDLINE | ID: mdl-35323805

ABSTRACT

Rechargeable lithium-ion batteries have drawn extensive attention owing to increasing demands in applications from portable electronic devices to energy storage systems. In situ polymerization is considered one of the most promising approaches for enabling interfacial issues and improving compatibility between electrolytes and electrodes in batteries. Herein, we observed in situ thermally induced electrolytes based on an oxetane group with LiFSI as an initiator, and investigated structural characteristics, physicochemical properties, contacting interface, and electrochemical performances of as-prepared SPEs with a variety of technologies, such as FTIR, 1H-NMR, FE-SEM, EIS, LSV, and chronoamperometry. The as-prepared SPEs exhibited good thermal stability (stable up to 210 °C), lower activation energy, and high ionic conductivity (>0.1 mS/cm) at 30 °C. Specifically, SPE-2.5 displayed a comparable ionic conductivity (1.3 mS/cm at 80 °C), better interfacial compatibility, and a high Li-ion transference number. The SPE-2.5 electrolyte had comparable coulombic efficiency with a half-cell configuration at 0.1 C for 50 cycles. Obtained results could provide the possibility of high ionic conductivity and good compatibility through in situ polymerization for the development of Li-ion batteries.

11.
Membranes (Basel) ; 12(4)2022 Apr 18.
Article in English | MEDLINE | ID: mdl-35448409

ABSTRACT

The polymer electrolytes are considered to be an alternative to liquid electrolytes for lithium-ion batteries because of their high thermal stability, flexibility, and wide applications. However, the polymer electrolytes have low ionic conductivity at room temperature due to the interfacial contact issue and the growing of lithium dendrites between the electrolytes/electrodes. In this study, we prepared gel polymer electrolytes (GPEs) through an in situ thermal-induced cationic ring-opening strategy, using LiFSI as an initiator. As-synthesized GPEs were characterized with a series of technologies. The as-synthesized PNDGE 1.5 presented good thermal stability (up to 150 °C), low glass transition temperature (Tg < −40 °C), high ionic conductivity (>10−4 S/cm), and good interfacial contact with the cell components and comparable anodic oxidation voltage (4.0 V). In addition, PNGDE 1.5 exhibited a discharge capacity of 131 mAh/g after 50 cycles at 0.2 C and had a 92% level of coulombic efficiency. Herein, these results can contribute to developing of new polymer electrolytes and offer the possibility of good compatibility through the in situ technique for Li-ion batteries.

12.
Membranes (Basel) ; 11(3)2021 Feb 27.
Article in English | MEDLINE | ID: mdl-33673539

ABSTRACT

Improved proton conductivity and high durability are now a high concern for proton exchange membranes (PEMs). Therefore, highly proton conductive PEMs have been synthesized from branched sulfonimide-based poly(phenylenebenzophenone) (SI-branched PPBP) with excellent thermal and chemical stability. The branched polyphenylene-based carbon-carbon backbones of the SI-branched PPBP membranes were attained from the 1,4-dichloro-2,5-diphenylenebenzophenone (PBP) monomer using 1,3,5-trichlorobenzene as a branching agent (0.1%) via the Ni-Zn catalyzed C-C coupling reaction. The as-synthesized SI-branched PPBP membranes showed 1.00~1.86 meq./g ion exchange capacity (IEC) with unique dimensional stability. The sulfonimide groups of the SI-branched PPBP membranes had improved proton conductivity (75.9-121.88 mS/cm) compared to Nafion 117 (84.74 mS/cm). Oxidation stability by thermogravimetric analysis (TGA) and Fenton's test study confirmed the significant properties of the SI-branched PPBP membranes. Additionally, a very distinct microphase separation between the hydrophobic and hydrophilic moieties was observed using atomic force microscopic (AFM) analysis. The properties of the synthesized SI-branched PPBP membranes demonstrate their viability as an alternative PEM material.

13.
RSC Adv ; 11(10): 5456-5465, 2021 Jan 28.
Article in English | MEDLINE | ID: mdl-35423097

ABSTRACT

A highly sensitive and selective colorimetric assay for the dual detection of Hg2+ and As3+ using gold nanoparticles (AuNPs) conjugated with d-penicillamine (DPL) was developed. When Hg2+ and As3+ ions coordinate with AuNP-bound DPLs, the interparticle distance decreases, inducing aggregation; this results in a significant color change from wine red to dark midnight blue. The Hg4f and As3d signals in the X-ray photoelectron spectra of Hg2+ (As3+)-DPL-AuNPs presented binding energies indicative of Hg2+-N(O) and As3+-N(O) bonds, and the molecular fragment observed in time-of-flight secondary ion mass spectra confirmed that Hg2+ and As3+ coordinated with two oxygen and two nitrogen atoms in DPL. The detection of Hg2+ and As3+ can be accomplished by observing the color change with the naked eye or by photometric methods, and this was optimized to provide optimal probe sensitivity. The assay method can be applied for environmental monitoring by first selectively quantifying Hg2+ in water samples at pH 6, then estimating the As3+ concentration at pH 4.5. The efficiency of the DPL-AuNP probe was evaluated for the sequential quantification of Hg2+ and As3+ in tap, pond, waste, and river water samples, and absorbance ratios (A 730/A 525) were correlated with Hg2+ and As3+ concentrations in the linear range of 0-1.4 µM. The limits of detection in water samples were found to be 0.5 and 0.7 nM for Hg2+ and As3+, respectively. This novel probe can be utilized for the dual determination of Hg2+ and As3+, even in the presence of interfering substances in environmental samples.

14.
Membranes (Basel) ; 11(1)2021 Jan 12.
Article in English | MEDLINE | ID: mdl-33445796

ABSTRACT

Polymer membranes, having improved conductivity with enhanced thermal and chemical stability, are desirable for proton exchange membranes fuel cell application. Hence, poly(benzophenone)s membranes (SI-PBP) containing super gas-phase acidic sulfonyl imide groups have been prepared from 2,5-dichlorobenzophenone (DCBP) monomer by C-C coupling polymerization using Ni (0) catalyst. The entirely aromatic C-C coupled polymer backbones of the SI-PBP membranes provide exceptional dimensional stability with rational ion exchange capacity (IEC) from 1.85 to 2.30 mS/cm. The as-synthesized SI-PBP membranes provide enhanced proton conductivity (107.07 mS/cm) compared to Nafion 211® (104.5 mS/cm). The notable thermal and chemical stability of the SI-PBP membranes have been assessed by the thermogravimetric analysis (TGA) and Fenton's test, respectively. The well distinct surface morphology of the SI-PBP membranes has been confirmed by the atomic force microscopy (AFM). These results of SI-PBP membranes comply with all the requirements for fuel cell applications.

15.
J Nanosci Nanotechnol ; 21(3): 1845-1853, 2021 03 01.
Article in English | MEDLINE | ID: mdl-33404458

ABSTRACT

Thermally and chemically stable, sulfonyl imide-based polymer blends have been prepared from sulfonimide poly(arylene ether sulfone) (SI-PAES) and sulfonimide Parmax-1200 (SI-Parmax-1200) using the solvent casting method. Initially, sulfonimide poly(arylene ether sulfone) (SI-PAES) polymers have typically been synthesized via direct polymerization of bis(4-chlorophenyl) sulfonyl imide (SI-DCDPS) and bis(4-fluorophenyl) sulfone (DFDPS) with bisphenol A (BPA). Subsequently, SI-Parmax-1200 has been synthesized via post-modification of the existing Parmax-1200 polymer followed by sulfonation and imidization. The SI-PAES/SI-Parmax-1200 blend membranes show high ion exchange capacity ranging from 1.65 to 1.97 meq/g, water uptake ranging from 22.8 to 65.4% and proton conductivity from 25.9 to 78.5 mS/cm. Markedly, the SI-PAES-40/SI-Parmax-1200 membrane (blended-40) exhibits the highest proton conductivity (78.5 mS/cm), which is almost similar to Nafion 117® (84.73 mS/cm). The thermogravimetric analysis (TGA) and Fenton's test confirm the excellent thermal and chemical stability of the synthetic polymer blends. Furthermore, the scanning electron microscopy (SEM) study shows a distinct phase separation at the hydrophobic/hydrophilic segments, which facilitate proton conduction throughout the ionic channel of the blend polymers. Therefore, the synthetic polymer blends represent an alternative to Nafion 117® as proton exchangers for fuel cells.

16.
ACS Appl Mater Interfaces ; 13(29): 34102-34113, 2021 Jul 28.
Article in English | MEDLINE | ID: mdl-34261308

ABSTRACT

UV-cured cross-linked polymer electrolytes are promising electrolytes for safe Li-ion batteries (LIBs) application due to their excellent conduction ability, low glass-transition temperature (Tg), and high discharge capacity. Herein, we have prepared novel fluorosulfonylimide methacrylic-based cross-linked polymer electrolyte membranes for LIBs via UV-curing process, which is a well-known, easy, low-cost, fast, and reliable technique. The synthesized UV-reactive novel methacrylate monomer with directly attached fluorosulfonylimide functional group methacryloylcarbamoyl sulfamoyl fluoride (MACSF) was used as a precursor for UV curing along with poly(ethylene glycol) dimethacrylate (PEGDMA) and lithium bis(fluorosulfonyl)imide (LiFSI). The results demonstrated that the cross-linked membrane with an optimized amount (30 wt %) of MACSF monomer (noted as CPE-3) showed the best performance. The nonflammable fluorosulfonyl group (a hydrophilic group of MACSF monomer) in the polymer matrix formed a wide channel, as a result of which Li ion can migrate easily via forming an ionic linkage. The CPE-3 electrolyte exhibited a low Tg (-79 °C), excellent phase separation, high conductivity (σ) (ca. 3.5 × 10-4 and 8.50 × 10-3 S·cm-1 at 30 and 80 °C, respectively), and high flame retardancy. The battery performance of half-cell (LiFePO4/CPE-3/Li) and full cell (LiFePO4/CPE-3/graphite) with CPE-3 electrolyte were attractive: discharge capacities (155 and 152 mAh/g) with the capacity retentions of 96.17 and 95.17% after 500 cycles at 0.1 C rate for half-cell and full-cell LIBs, respectively.

17.
Anal Chim Acta ; 1148: 238178, 2021 Mar 01.
Article in English | MEDLINE | ID: mdl-33516382

ABSTRACT

A tetraphenylethene (TPE) derivative was designed and synthesized upon conjugation with bis(thiophen-2-ylmethyl) amine (BTA) containing a mercury-binding moiety and further characterized by using Nuclear magnetic resonance (NMR), LC-MS, UV-Vis, and fluorescence spectroscopic methods. The resulting TPE-BTA exhibited comprehensive aggregation-induced emission while expressing a high quantum yield and emission intensity at 70% water fraction. The probe exhibited a good photochromic effect with a Stokes shift of 178 nm, and the emission intensity at 550 nm increased considerably with the color turning from dark green to bright green under a UV lamp upon the addition of 5 µM Hg2+. The lowest-energy conformation of the probe showed that two thiophene rings were perpendicular to the phenyl ring, while two BTA molecules were situated in a staggered form to each other. The sulfur and nitrogen atoms present in TPE-BTA were coordinated to the Hg2+ ion, and these binding sites were confirmed by the NMR parameters, X-ray photoelectron spectroscopy signals, and structural calculations. The binding of Hg2+ to TPE-BTA was believed to restrict the intramolecular motion of TPE-BTA, thus inducing it to shine brighter according to the unique aggregation-induced emission effect. The concentration of Hg2+ was determined based on the enhancement of the emission intensity, and the present probe showed an extremely high sensitivity with a limit of detection of 10.5 nM. Furthermore, TPE-BTA enabled selective detection of Hg2+ even in the presence of a 1000-fold excess of other interfering metal ions. The proposed method was successfully employed to determine Hg2+ in living HeLa cells and real water samples.


Subject(s)
Fluorescent Dyes , Mercury , HeLa Cells , Humans , Spectrometry, Fluorescence , Water
18.
Nutrients ; 12(6)2020 Jun 14.
Article in English | MEDLINE | ID: mdl-32545878

ABSTRACT

Although bariatric surgery is the best treatment modality for morbidly obese patients, a 10-30% rate of weight recidivism has been reported in various specialized centers. We examined changes in energy and macronutrients after bariatric surgery and performed analysis to establish appropriate nutritional guidelines for reaching the target percentage of weight loss after surgery. A total of 189 subjects who underwent bariatric surgery were classified into success and failure groups depending on whether or not they reached 50% loss of excess weight at 12 months after bariatric surgery. Physical examinations and dietary surveys were completed before and 1, 6, and 12 months after surgery. Using receiver operating characteristic (ROC) analysis, the optimal cutoff points for nutrient intakes for determining success after bariatric surgery were computed based on maximal Youden's index. At 6 and 12 months after surgery, the success group had significantly lower carbohydrate and fat intakes than the failure group. The cutoff calorie intake for success in weight loss was <835.0, <1132.5, and <1523.0 kcal/day at 1, 6, and 12 months post operation, respectively. With regard to protein, the cutoff intakes were >44.5, >41.5, and >86.5 g/day at 1, 6, and 12 months post operation, respectively. At 12 months, the cutoff ratio for energy obtained from carbohydrates, protein, and fat was <49.0, >24.5, and <28.0%, respectively. Our findings confirm that the level of diet control and nutrition restriction affect the achievement of target weight loss, emphasizing that long-term weight loss is related to compliance with nutrient recommendations.


Subject(s)
Bariatric Surgery , Eating/physiology , Energy Intake/physiology , Obesity/surgery , Weight Loss/physiology , Adult , Dietary Carbohydrates/administration & dosage , Dietary Fats/administration & dosage , Female , Humans , Male , Middle Aged , Nutrition Policy , Retrospective Studies , Treatment Outcome
19.
J Appl Physiol (1985) ; 129(4): 732-747, 2020 10 01.
Article in English | MEDLINE | ID: mdl-32758040

ABSTRACT

This study aims to develop a one-dimensional (1D) computational fluid dynamics (CFD) model with dynamic airway geometry that considers airway wall compliance and acinar dynamics. The proposed 1D model evaluates the pressure distribution and the hysteresis between the pressure and tidal volume (Vtidal) in the central and terminal airways for healthy and asthmatic subjects. Four-dimensional CT images were captured at 11-14 time points during the breathing cycle. The airway diameter and length were reconstructed using a volume-filling method and a stochastic model at respective time points. The obtained values for the airway diameter and length were interpolated via the Akima spline to avoid unboundedness. A 1D energy balance equation considering the effects of wall compliance and parenchymal inertance was solved using the efficient aggregation-based algebraic multigrid solver, a sparse matrix solver, reducing the computational costs by around 90% when compared with the generalized minimal residual solver. In the Vtidal versus displacement in the basal direction (z-coordinate), the inspiration curve was lower than the expiration curve, leading to relative hysteresis. The dynamic deformation model was the major factor influencing the difference in the workload in the central and terminal airways. In contrast, wall compliance and parenchymal inertance appeared only marginally to affect the pressure and workload. The integrated 1D model mimicked dynamic deformation by predicting airway diameter and length at each time point, describing the effects of wall compliance and parenchymal inertance. This computationally efficient model could be utilized to assess breathing mechanism as an alternative to pulmonary function tests.NEW & NOTEWORTHY This study introduces a one-dimensional (1D) computational fluid dynamics (CFD) model mimicking the realistic changes in diameter and length in whole airways and reveals differences in lung deformation between healthy and asthmatic subjects. Utilizing computational models, the effects of parenchymal inertance and airway wall compliance are investigated by changing ventilation frequency and airway wall elastance, respectively.


Subject(s)
Asthma , Lung , Computer Simulation , Humans , Models, Biological , Respiration , Respiratory Function Tests
20.
ACS Appl Mater Interfaces ; 11(38): 34930-34938, 2019 Sep 25.
Article in English | MEDLINE | ID: mdl-31469269

ABSTRACT

Single-ion conducting polymer electrolyte (SICPE) is a safer alternative to the conventional high-performance liquid electrolyte for Li-ion batteries. The performance of SICPEs-based Li-ion batteries is limited due to the low Li+ conductivities of SICPEs at room temperature. Herein, we demonstrated the synthesis of a novel SICPE, poly(ethylene-co-acrylic lithium (fluoro sulfonyl)imide) (PEALiFSI), with acrylic (fluoro sulfonyl)imide anion (AFSI). The solvent- and plasticizer-free PEALiFSI electrolyte, which was assembled at 90 °C under pressure, exhibited self-healing properties with remarkably high Li+ conductivity (5.84 × 10-4 S cm-1 at 25 °C). This is mainly due to the self-healing behavior of this electrolyte, which induced to increase the proportion of the amorphous phase. Additionally, the weak interaction of Li+ with the resonance-stabilized AFSI anion is also responsible for high Li+ conductivity. This self-healed SICPE showed high Li+ transference number (ca. 0.91), flame and heat retardancy, and good thermal stability, which concurrently delivered ca. 88.25% (150 mAh g-1 at 0.1C) of the theoretical capacitance of LiFePO4 cathode material at 25 °C with the full-cell configuration of LiFePO4/PEALiFSI/graphite. Furthermore, the self-healed PEALiFSI-based all-solid-state Li battery showed high electrochemical cycling stability with the capacity retention of 95% after 500 charge-discharge cycles.

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