Combining pseudocapacitive materials with carbon materials, such as graphene, is a promising strategy to enhance their performance. In this study, we present a novel and feasible approach involving the alternating electrodeposition of reduced graphene oxide (rGO) and nickel-cobalt layered double hydroxide (NiCo-LDH) onto carbon cloth (CC) current collectors to fabricate binder-free supercapacitor electrodes with a layered LDH/rGO/LDH/rGO/CC architecture. The rGO layers are not only coated on CC substrate to regulate the electrodeposition of LDH nanosheets, but also interposed between the LDH layers to further enhance conductivity and provide buffering effects.
View Article and Find Full Text PDFImproving the morphological structure of active materials is a reliable strategy for the fabrication of high-performance supercapacitor electrodes. In this study, we introduce a feasible approach to constructing the graphene/polypyrrole (PPy) composite film implanted onto the current collector through a two-step electrochemical deposition method utilizing MnO as an intermediary template. The reduced graphene oxide (rGO) hydrogel film is first hydrothermally grown on a carbon cloth (CC) substrate to obtain a porous rGO@CC electrode on which MnO is electrodeposited.
View Article and Find Full Text PDFBackground: Educational duration might play a vital role in preventing the occurrence and development of osteoporosis(OP).
Purpose: To assess the causal effect of educational duration on bone mineral density(BMD) and risk factors for OP by Mendelian randomization(MR) study.
Methods: The causal relationship was analyzed using data from genome-wide association study(GWAS).
Objective: Several epidemiological studies have identified a potential link between serum uric acid (UA), gout, and sepsis. The primary objective of this study is to delve deeper into this connection, investigating the causal effect of UA and gout on sepsis by applying Mendelian randomization (MR). Methods: The causal relationship was analyzed using data from Genome-Wide Association Study (GWAS).
View Article and Find Full Text PDFThe facile and cost-effective preparation of supercapacitor electrodes is significant for the application of this kind of electrochemical energy-storing module. In this work, we designed a feasible strategy to fabricate a binary active material onto a current collector in one step. A colloidal mixture of graphene oxide and pyrrole layered on a carbon cloth could undergo a redox reaction through a mild hydrothermal process to yield a reduced graphene oxide/polypyrrole hydrogel film anchored onto the carbon cloth.
View Article and Find Full Text PDFPhys Chem Chem Phys
September 2022
Ion accumulation in perovskite solar cells can be highly suppressed by a mesoporous TiO layer. This is evidenced by the decrease of the ion-related electrostatic potential with increasing the thickness of the mesoporous layer, accounted for by the electron population in the shallow trap states of the TiO nanocrystals.
View Article and Find Full Text PDFBackground: Immune checkpoint inhibitors (ICIs) treatment among cancer patients has been shown to have antiviral effects by reactivating exhausted T cells. However, they could also trigger inflammatory storm. Therefore, prior exposure to ICIs may influence the risk of SARS-CoV2 infection and subsequent mortality.
View Article and Find Full Text PDFGrain boundary trap passivation in perovskite films has become one of the most effective strategies for suppressing the charge recombination and enhancing the photovoltaic performance of perovskite solar cells, whereas the relevant trap-state properties and the charge carrier dynamics need to be further clarified. In this work, the CH3NH3Cl (MACl) additive is introduced into the MAI:PbI2 precursor solution to obtain perovskite films comprising various grain sizes with distinct grain boundaries and trap-state properties. The influence of grain boundary traps passivated with the MACl additive on trap-state properties and charge carrier transport/recombination dynamics is systematically studied with time-resolved spectroscopic and transient photoelectric characterization.
View Article and Find Full Text PDFZhonghua Wei Zhong Bing Ji Jiu Yi Xue
November 2020
Objective: To analyze the clinical characteristics and related influencing factors of carbapenem resistant Klebsiella pneumoniae (CRKP) in patients with artificial airway and mechanical ventilation in intensive care unit (ICU), and provide theoretical basis for clinical prevention of Klebsiella pneumoniae infection.
Methods: The clinical data of patients with pulmonary infection of Klebsiella pneumoniae in ICU of Beijing Shijitan Hospital Affiliated to Capital Medical University from January 2016 to December 2019 were collected. Compared CRKP pneumonia patients (study group) with carbapenem antibiotic sensitive Klebsiella pneumoniae (CSKP) pneumonia patients (control group), the clinical characteristics [gender, age, acute physiology and chronic health evaluation II (APACHE II), duration of mechanical ventilation, proportion of patients with mechanical ventilation > 10 days, use of antibiotics before detection of Klebsiella pneumoniae, white blood cell count (WBC), C-reactive protein (CRP), procalcitonin (PCT), albumin, bedridden for more than 1 month before admission, 28-day mortality] were analyzed.
Despite the outstanding photovoltaic performance of perovskite solar cells, the correlation between the electron transport layer and the mechanism of photoelectric conversion is still not fully understood. In this paper, the relationship between photovoltaic performance and carrier dynamics is systematically studied in both TiO- and SnO-based planar perovskite devices. It is found that the different electron transport layers result in distinct forward scan results and charge dynamics.
View Article and Find Full Text PDFThe modification of the inorganic hole transport layer has been an efficient method for optimizing the performance of inverted perovskite solar cells. In this work, we propose a facile modification of a compact NiO film with NiO nanoparticles and explore the effects on the charge carrier dynamic behaviors and photovoltaic performance of inverted perovskite devices. The modification of the NiO hole transport layer can not only enlarge the surface area and infiltration ability, but also adjust the valence band maximum to well match that of perovskite.
View Article and Find Full Text PDFIn this paper, one-step preparation of graphene/gold nanoparticle hydrogel film through the hydrothermal method is reported. The hydrogel film could be formed on a glass substrate under hydrothermal conditions, and upon freeze-drying, the aerogel film of 40 μm thickness with satisfying flexibility and strength is obtained. The aerogel composite film is characterized by scanning/transmission electron microscopy, X-ray diffraction, Raman spectroscopy and X-ray photoelectron spectroscopy.
View Article and Find Full Text PDFPhys Chem Chem Phys
March 2019
The compositional engineering is of great importance to tune the electrical and optical properties of perovskite and improve the photovoltaic performance of perovskite solar cells. The exploration of the corresponding photoelectric conversion processes, especially the carrier recombination dynamics, will contribute to the optimization of the devices. In this work, perovskite with mixed methylammonium (MA) and formamidinium (FA) as organic cations, MA0.
View Article and Find Full Text PDFDipeptidyl Peptidase-IV (DPP-4) is a validated therapeutic target for type 2 diabetes. Aiming to interact with both residues Try629 and Lys554 in S' site, a series of novel uracil derivatives 1a-l and 2a-i incorporating benzoic acid moieties at the N position were designed and evaluated for their DPP-4 inhibitory activity. Structure-activity relationships (SAR) study led to the identification of the optimal compound 2b as a potent and selective DPP-4 inhibitor (IC = 1.
View Article and Find Full Text PDFOrganic-inorganic halide perovskites have attracted enormous attention owing to their promising application in photovoltaic devices. The morphology of the perovskites is the key to driving the performance of perovskite devices, which necessitates a systematic study. In this work, two typical morphologies, i.
View Article and Find Full Text PDFActa Crystallogr C Struct Chem
February 2018
A dimerized 1,3-diazaazulene derivative, namely 1,4-bis(1,3-diazaazulen-2-yl)benzene [or 2,2'-(1,4-phenylene)bis(1,3-diazaazulene)], CHN, (I), has been synthesized successfully through the condensation reaction between 2-methoxytropone and benzene-1,4-dicarboximidamide hydrochloride, and was characterized by H NMR and C NMR spectroscopies, and ESI-MS. X-ray diffraction analysis reveals that (I) has a nearly planar structure with good π-electron delocalization, indicating that it might serve as a π building block. The crystal belongs to the monoclinic system.
View Article and Find Full Text PDFInteract Cardiovasc Thorac Surg
April 2018
Objectives: There is increasing evidence that dual antiplatelet therapy (DAPT) when compared with single antiplatelet therapy may improve venous graft patency after coronary artery bypass graft. However, it is not yet known whether postoperative administration of DAPT may increase the potential risk of bleeding, especially in the early postoperative period.
Methods: We searched studies on PubMed, Embase, Web of Science and the Cochrane Central Register of Controlled Trials.
The photovoltaic performance of organic-inorganic hybrid perovskite solar cells has reached a bottleneck after rapid development in last few years. Further breakthrough in this field requires deeper understanding of the underlying mechanism of the photoelectric conversion process in the device, especially the dynamics of charge-carrier recombination. Originating from dye-sensitized solar cells (DSSCs), mesoporous-structured perovskite solar cells (MPSCs) have shown many similarities to DSSCs with respect to their photoelectric dynamics.
View Article and Find Full Text PDFPhys Chem Chem Phys
August 2017
Perovskite solar cells have emerged as promising photovoltaic systems with superb power conversion efficiency. For the practical application of perovskite devices, the greatest concerns are the power output density and the related dynamics under working conditions. In this study, the working conditions of planar and mesoscopic perovskite solar cells are simulated and the power output density evolutions with the working voltage are highlighted.
View Article and Find Full Text PDFOrganic-inorganic halide perovskite solar cells have rapidly come to prominence in the photovoltaic field. In this context, CH NH PbI , as the most widely adopted active layer, has been attracting great attention. Generally, in a CH NH PbI layer, unreacted PbI inevitably coexists with the perovskite crystals, especially following a two-step fabrication process.
View Article and Find Full Text PDFPerovskite films with different particle sizes and PbI contents were prepared by using a controlled single or sequential method. By means of temperature-dependent fluorescence spectroscopy, the energetic distribution of intrinsic intragap trap states in perovskite was quantitatively determined, and the radiative charge recombinations through the band edge and via trap states were studied. Furthermore, a series of thermodynamic parameters, such as the demarcation energy between radiative and nonradiative recombination regions, detrapping activation energy, and characteristic temperature, were extracted based on which of the possible radiative and nonradiative recombination mechanisms were proposed.
View Article and Find Full Text PDFMultiwalled carbon nanotubes (MWCNTs) on polystyrene (PS) microspheres have been designed and prepared by layer-by-layer assembly via electrostatic interaction. MWCNTs@PS was characterized by scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The new materials were employed as a novel solid-phase microextraction (SPME) coating to enrich trace level of phthalate acid esters (PAEs) in water samples.
View Article and Find Full Text PDFOrganic-inorganic halide perovskite solar cells are becoming the next big thing in the photovoltaic field owing to their rapidly developing photoelectric conversion performance. Herein, mesoporous structured perovskite devices with various perovskite grain sizes are fabricated by a sequential dropping method, and the charge recombination dynamics is investigated by transient optical-electric measurements. All devices exhibit an overall power conversion efficiency around 15%.
View Article and Find Full Text PDFCharge recombination dynamics in intrinsic perovskite film and in meso-superstructured perovskite solar cells have been systematically studied, which are found to be mediated by the energetic distribution of intra-gap trap states as described by the trap-limited recombination theory. Besides, the passivation effect of the hole-transport material on trap states is discussed.
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