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1.
Sensors (Basel) ; 24(11)2024 Jun 04.
Article En | MEDLINE | ID: mdl-38894418

Metal-oxide-based gas sensors are extensively utilized across various domains due to their cost-effectiveness, facile fabrication, and compatibility with microelectronic technologies. The copper (Cu)-based multifunctional polymer-enhanced sensor (CuMPES) represents a notably tailored design for non-invasive environmental monitoring, particularly for detecting diverse gases with a low concentration. In this investigation, the Cu-CuO/PEDOT nanocomposite was synthesized via a straightforward chemical oxidation and vapor-phase polymerization. Comprehensive characterizations employing X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), X-ray diffraction (XRD), and micro Raman elucidated the composition, morphology, and crystal structure of this nanocomposite. Gas-sensing assessments of this CuMPES based on Cu-CuO/PEDOT revealed that the response current of the microneedle-type CuMPES surpassed that of the pure Cu microsensor by nearly threefold. The electrical conductivity and surface reactivity are enhanced by poly (3,4-ethylenedioxythiophene) (PEDOT) polymerized on the CuO-coated surface, resulting in an enhanced sensor performance with an ultra-fast response/recovery of 0.3/0.5 s.

2.
Materials (Basel) ; 17(9)2024 Apr 24.
Article En | MEDLINE | ID: mdl-38730786

Developing argyrodite-type, chlorine-rich, sodium-ion, solid-state electrolytes with high conductivity is a long-term challenge that is crucial for the advancement of all-solid-state batteries (ASSBs). In this study, chlorine-rich, argyrodite-type Na6-xPS5-xCl1+x solid solutions were successfully developed with a solid solution formation range of 0 ≤ x ≤ 0.5. Na5.5PS4.5Cl1.5 (x = 0.5), displaying a highest ionic conductivity of 1.2 × 10-3 S/cm at 25 °C, which is more than a hundred times higher than that of Na6PS5Cl. Cyclic voltammetry and electrochemical impedance spectroscopy results demonstrated that the rich chlorine significantly enhanced the ionic conductivity and electrochemical stability, in addition to causing a reduction in activation energy. The Na5.5PS4.5Cl1.5 composite also showed the characteristics of a pure ionic conductor without electronic conductivity. Finally, the viability of Na5.5PS4.5Cl1.5 as a sodium electrolyte for all-solid-state sodium batteries was checked in a lab-scale ASSB, showing stable battery performance. This study not only demonstrates new composites of sodium-ionic, solid-state electrolytes with relatively high conductivity but also provides an anion-modulation strategy to enhance the ionic conductivity of argyrodite-type sodium solid-state ionic conductors.

3.
Chem Rec ; 24(1): e202300302, 2024 Jan.
Article En | MEDLINE | ID: mdl-38010947

As supercapacitor (SC) technology continues to evolve, there is a growing need for electrode materials with high energy/power densities and cycling stability. However, research and development of electrode materials with such characteristics is essential for commercialization the SC. To meet this demand, the development of superior electrode materials has become an increasingly critical step. The electrochemical performance of SCs is greatly influenced by various factors such as the reaction mechanism, crystal structure, and kinetics of electron/ion transfer in the electrodes, which have been challenging to address using previously investigated electrode materials like carbon and metal oxides/sulfides. Recently, tellurium and telluride-based materials have garnered increasing interest in energy storage technology owing to their high electronic conductivity, favorable crystal structure, and excellent volumetric capacity. This review provides a comprehensive understanding of the fundamental properties and energy storage performance of tellurium- and Te-based materials by introducing their physicochemical properties. First, we elaborate on the significance of tellurides. Next, the charge storage mechanism of functional telluride materials and important synthesis strategies are summarized. Then, research advancements in metal and carbon-based telluride materials, as well as the effectiveness of tellurides for SCs, were analyzed by emphasizing their essential properties and extensive advantages. Finally, the remaining challenges and prospects for improving the telluride-based supercapacitive performance are outlined.

4.
Nanomaterials (Basel) ; 12(18)2022 Sep 11.
Article En | MEDLINE | ID: mdl-36144942

The interaction between cathode and anode materials is critical for developing a high-performance asymmetric supercapacitor (SC). Significant advances have been made for cathode materials, while the anode is comparatively less explored for SC applications. Herein, we proposed a high-performance binder-free anode material composed of two-dimensional ZnFe2O4 nanoflakes supported on carbon cloth (ZFO-NF@CC). The electrochemical performance of ZFO-NF@CC as an anode material for supercapacitor application was examined in a KOH solution via a three-electrode configuration. The ZFO-NF@CC electrode demonstrated a specific capacitance of 509 F g-1 at 1.5 A g-1 and was retained 94.2% after 10,000 GCD cycles. The ZFO-NF@CC electrode showed exceptional charge storage properties by attaining high pseudocapacitive-type storage. Furthermore, an asymmetric SC device was fabricated using ZFO-NF@CC as an anode and activated carbon on CC (AC@CC) as a cathode with a KOH-based aqueous electrolyte (ZFO-NF@CC||AC@CC). The ZFO-NF@CC||AC@CC yielded a high specific capacitance of 122.2 F g-1 at a current density of 2 A g-1, a high energy density of 55.044 Wh kg-1 at a power density of 1801.44 W kg-1, with a remarkable retention rate of 96.5% even after 4000 cycles was attained. Thus, our results showed that the enhanced electrochemical performance of ZFO-NF@CC used as an anode in high-performance SC applications can open new research directions for replacing carbon-based anode materials.

5.
Nanomaterials (Basel) ; 13(1)2022 Dec 26.
Article En | MEDLINE | ID: mdl-36616031

A high capacitance and widened voltage frames for an aqueous supercapacitor system are challenging to realize simultaneously in an aqueous medium. The severe water splitting seriously restricts the narrow voltage of the aqueous electrolyte beyond 2 V. To overcome this limitation, herein, we proposed the facile wet-chemical synthesis of a new CuSe-TiO2-GO ternary nanocomposite for hybrid supercapacitors, thus boosting the specific energy up to some maximum extent. The capacitive charge storage mechanism of the CuSe-TiO2-GO ternary nanocomposite electrode was tested in an aqueous solution with 3 M KOH as the electrolyte in a three-cell mode assembly. The voltammogram analysis manifests good reversibility and a remarkable capacitive response at various currents and sweep rates, with a durable rate capability. At the same time, the discharge/charge platforms realize the most significant capacitance and a capacity of 920 F/g (153 mAh/g), supported by the impedance analysis with minimal resistances, ensuring the supply of electrolyte ion diffusion to the active host electrode interface. The built 2 V CuSe-TiO2-GO||AC-GO||KOH hybrid supercapacitor accomplished a significant capacitance of 175 F/g, high specific energy of 36 Wh/kg, superior specific power of 4781 W/kg, and extraordinary stability of 91.3% retention relative to the stable cycling performance. These merits pave a new way to build other ternary nanocomposites to achieve superior performance for energy storage devices.

7.
Case Rep Nephrol ; 2018: 4627890, 2018.
Article En | MEDLINE | ID: mdl-29977633

Difluoroethane is the active ingredient in various computer cleaners and is increasingly abused by teenagers due to its ease of access, quick onset of euphoric effects, and lack of detectability on current urine drug screens. The substance has detrimental effects on various organ systems; however, its effects on the kidneys remain largely unreported. The following case report adds new information to the developing topic of acute kidney injury in patients abusing difluoroethane inhalants. In addition, it is one of the first to show a possible relationship between prolonged difluoroethane abuse and the development of chronic kidney disease in the absence of other predisposing risk factors.

8.
J Vasc Access ; 18(6): 482-487, 2017 Nov 17.
Article En | MEDLINE | ID: mdl-28708199

INTRODUCTION: Transposed basilic vein arteriovenous fistulas suffer from stenosis at their basilic angle of transposition (BAT). This lesion exhibits frequent recurrence after angioplasty. The primary goal of this study was to determine the effect of stent-graft placement on BAT lesion- and access-patency. The secondary goals were to determine the frequency of intervention pre- and post-stent placement and stent-associated stenosis. METHODS: Thirty-seven cases had stent-grafts placed at their BAT to manage stenosis. Cases served as their own controls by analyzing their lesion- and access-patency pre- and post-stent placement. Student's t-test was used for analysis of continuous variables. Categorical variables were evaluated by Fisher's exact test. Tests were considered significant when p was ≤0.05. RESULTS: At 6 and 12 months, pre-stent lesion primary patency rates were 29% and 3%, and post-stent were 57% and 40%, respectively. Lesion primary assisted patency rates were 39% and 13%, and post-stent were 91% and 80%, respectively. At 6 and 12 months, pre-stent access primary patency rates were 29% and 3%, and post-stent were 26% and 19%, respectively. Pre-stent primary access assisted patency rates were 36% and 10%, and post-stent were 82% and 75%, respectively. Lesion intervention rates averaged 0.47/month pre-stent and 0.13/month post-stent. Access intervention rate averaged 0.50/month pre-stent, and 0.15/month post-stent. Stent-associated stenosis was seen in 23 cases. CONCLUSIONS: Treatment of BAT stenosis with stent-grafts had positive impact on the target lesion and the dialysis access circuit.


Arteriovenous Shunt, Surgical/adverse effects , Blood Vessel Prosthesis Implantation/adverse effects , Endovascular Procedures/adverse effects , Graft Occlusion, Vascular/surgery , Renal Dialysis , Upper Extremity/blood supply , Arteriovenous Shunt, Surgical/instrumentation , Blood Vessel Prosthesis , Blood Vessel Prosthesis Implantation/instrumentation , Case-Control Studies , Databases, Factual , Endovascular Procedures/instrumentation , Female , Graft Occlusion, Vascular/diagnostic imaging , Graft Occlusion, Vascular/etiology , Graft Occlusion, Vascular/physiopathology , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Phlebography , Recurrence , Risk Factors , Stents , Time Factors , Treatment Outcome , Vascular Patency
9.
Semin Dial ; 28(2): E15-22, 2015.
Article En | MEDLINE | ID: mdl-25533577

The purpose of this study was to report the results obtained in a cohort of 520 cases of thrombosed arteriovenous fistulas (AVF) treated by percutaneous intervention over a period of 8 years. The methods used varied according to the individual characteristics of the case. A clinical success rate of 91.1% was obtained with no significant difference being noted among radial-cephalic, brachial-cephalic, and brachial-basilic AVFs. The mean primary patency for this group was 227.3 ± 14.6 days, and the mean assisted primary patency was 677.2 ± 44.6 days. The lower arm AVFs had both a primary patency and an assisted primary patency that were significantly better than the upper arm cases (p = 0.006 and 0.002, respectively). The primary patency for radial-cephalic AVFs was significantly better than that for brachial-cephalic AVFs (p = 0.021), but not for brachial-basilic cases (p = 0.122). Assisted primary patency for radial-cephalic cases was significantly superior to the values for either patients with a brachial cephalic (p = 0.046) or a brachial-basilic (p = 0.004). Complications occurred in seven cases (1.3%), all of which were venous ruptures. Blood flow was affected in four cases. Only one of these was salvaged with angioplasty balloon tamponade. In the remaining three cases, the AVF was lost.


Arteriovenous Shunt, Surgical/adverse effects , Endovascular Procedures/methods , Graft Occlusion, Vascular/surgery , Thrombectomy/methods , Thrombosis/surgery , Adult , Aged , Aged, 80 and over , Female , Follow-Up Studies , Graft Occlusion, Vascular/physiopathology , Humans , Kidney Failure, Chronic/therapy , Male , Middle Aged , Renal Dialysis , Thrombosis/physiopathology , Time Factors , Vascular Patency , Young Adult
10.
Semin Dial ; 27(6): 639-44, 2014.
Article En | MEDLINE | ID: mdl-24976160

Arteriovenous grafts (AVGs) suffer from high thrombosis rates. It is not known whether placement of stent grafts at the venous anastomosis (VA) of thrombosed AVGs would impact future thrombosis. This is a retrospective study evaluating a group of AVGs that underwent endovascular thrombectomy with placement of a stent graft at their VA. The study period was a minimum of 1 year or until kidney transplantation or death. Primary and secondary AVG patency rates were obtained using Kaplan-Meier survival estimates. Demographic parameters were analyzed using Cox multivariate analysis. The effect of early vs. late first thrombosis was also studied. Sixty-six patients were included in the study. Of these, 53 (80%) experienced ≥1 thrombotic event during the study period. Thrombosis led to AVG loss in 26 (39%). The primary patency was 47%, 35%, and 21% at 3, 6, and 12 months, respectively. The assisted primary patency was 50%, 38%, and 25% at 3, 6, and 12 months, respectively. The secondary patency rate was 85%, 76%, and 72% at 3, 6, and 12 months, respectively. Thus, poor primary patency rates were observed despite stent graft placement at the VA. In addition, early thrombosis following stent graft placement was associated with worse AVG outcomes.


Arteriovenous Shunt, Surgical/adverse effects , Blood Vessel Prosthesis Implantation , Graft Occlusion, Vascular/therapy , Kidney Failure, Chronic/therapy , Renal Dialysis , Thrombectomy , Adult , Aged , Aged, 80 and over , Blood Vessel Prosthesis , Graft Occlusion, Vascular/diagnosis , Graft Occlusion, Vascular/etiology , Humans , Male , Middle Aged , Retrospective Studies , Stents , Treatment Outcome , Vascular Patency
11.
Tsitol Genet ; 45(6): 10-27, 2011.
Article En | MEDLINE | ID: mdl-22329159

Bread wheat (Triticum aestivum L.) germplasm consisting of 45 genotypes were clustered phenotypically using ten morphological traits and Area Under Disease Progress Curve (AUDPC) as measure of stripe rust resistance. The clustering was ratified by using twenty three molecular markers (SSR, EST and STS) linked to stripe rust (Puccinia striiformis f. sp. tritici) resistant QTLs. The aim was to asses the extent of genetic variability among the genotypes in order to select the parents for crossing between the resistant and susceptible genotypes with respect to stripe rust. The Euclidian dissimilarity values resulted from phenotypic data regarding morphological traits and AUDPC were used to construct a dendrogram for clustering the accessions. Using un-weighted pair group method with arithmetic means, another dendrogram resulted from the similarity coefficient values was used to distinguish the genotypes with respect to stripe rust. Clustering based on phenotypic data produced two major groups and five clusters (with Euclidian dissimilarity ranging from 244 to 16.16) whereas genotypic data yielded two major groups and four clusters (with percent similarity coefficient values ranging from 0.1 to 46.0) to separate the gene pool into highly resistant, resistant, moderately resistant, moderately susceptible and susceptible genotypes. With few exceptions, the outcome of both type of clustering was almost similar and resistant as well as susceptible genotypes came in the same clusters of molecular genotyping as yielded by phenotypic clustering. As a result seven genotypes (Bakhtawar-92, Frontana, Saleem 2000, Tatara, Inqilab-91, Fakhre Sarhad and Karwan) of diverse genetic background were selected for pyramiding stripe rust resistant genes as well as some other agronomic traits after hybridization.


Basidiomycota/immunology , Genes, Plant , Mycoses/genetics , Plant Diseases/genetics , Plant Immunity/genetics , Selection, Genetic , Triticum/genetics , Breeding , Chromosome Mapping , Crosses, Genetic , Genetic Linkage , Genetic Markers , Genotype , Molecular Typing , Multigene Family , Mycoses/immunology , Mycoses/microbiology , Pakistan , Phenotype , Phylogeny , Phylogeography , Plant Diseases/immunology , Plant Diseases/microbiology , Polymorphism, Genetic , Quantitative Trait Loci
12.
Transplantation ; 78(10): 1560-3, 2004 Nov 27.
Article En | MEDLINE | ID: mdl-15599323

Daclizumab can decrease the incidence of acute rejection (AR) in renal transplant (RTx) recipients. In this prospective study, 52 RTx patients were divided into two groups according to the dose of daclizumab: 1 mg/kg on day 0 and every 14 days for five doses (group 1, n = 30) or a truncated regimen of 2 mg/kg on day 0 and on the day of discharge (group 2, n = 22). The following variables were recorded: demographics; delayed graft function; AR at 3, 6, and 12 months; time to AR; chronic allograft nephropathy (CAN); and serum creatinine. The overall incidences of AR were 23% and 27% (P = 0.76) in groups 1 and 2, respectively, whereas at 6 months they were 21% and 18% (P = 1.0). Median time to AR was 10 days in group 1 and 94 days in group 2 (P = 0.09). The incidence of CAN was 6.6% in group 1 and 13% in group 2 (P = 0.63). These data suggest that the truncated dose of daclizumab is as effective as the standard regimen for AR prophylaxis.


Antibodies, Monoclonal/therapeutic use , Graft Rejection/prevention & control , Immunoglobulin G/therapeutic use , Kidney Transplantation/immunology , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal, Humanized , Daclizumab , Dose-Response Relationship, Drug , Female , Humans , Immunoglobulin G/administration & dosage , Immunosuppressive Agents/administration & dosage , Immunosuppressive Agents/therapeutic use , Kidney Transplantation/mortality , Male , Middle Aged , Survival Analysis , Time Factors
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