Solution-processed small-molecule solar cells: breaking the 10% power conversion efficiency.

A two-dimensional conjugated small molecule (SMPV1) was designed and synthesized for high performance solution-processed organic solar cells. This study explores the photovoltaic properties of this molecule as a donor, with a fullerene derivative as an acceptor, using solution processing in single junction and double junction tandem solar cells. The single junction solar cells based on SMPV1 exhibited a certified power conversion efficiency of 8.02% under AM 1.5 G irradiation (100 mW cm(-2)). A homo-tandem solar cell based on SMPV1 was constructed with a novel interlayer (or tunnel junction) consisting of bilayer conjugated polyelectrolyte, demonstrating an unprecedented PCE of 10.1%. These results strongly suggest solution-processed small molecular materials are excellent candidates for organic solar cells

Influences of graphene oxide support on the electrochemical performances of graphene oxide-MnO2 nanocomposites

MnO2 supported on graphene oxide (GO) made from different graphite materials has been synthesized and further investigated as electrode materials for supercapacitors. The structure and morphology of MnO2-GO nanocomposites are characterized by X-ray diffraction, X-ray photoemission spectroscopy, scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and Nitrogen adsorption-desorption. As demonstrated, the GO fabricated from commercial expanded graphite (denoted as GO(1)) possesses more functional groups and larger interplane gap compared to the GO from commercial graphite powder (denoted as GO(2)). The surface area and functionalities of GO have significant effects on the morphology and electrochemical activity of MnO2, which lead to the fact that the loading amount of MnO2 on GO(1) is much higher than that on GO(2). Elemental analysis performed via inductively coupled plasma optical emission spectroscopy confirmed higher amounts of MnO2 loading on GO(1). As the electrode of supercapacitor, MnO2-GO(1) nanocomposites show larger capacitance (307.7 F g-1) and better electrochemical activity than MnO2-GO(2) possibly due to the high loading, good uniformity, and homogeneous distribution of MnO2 on GO(1) support

Interfacial Degradation of Planar Lead Halide Perovskite Solar Cells

ABSTRACT: The stability of perovskite solar cells is one of the major challenges for this technology to reach commercialization, with water believed to be the major degradation source. In this work, a range of devices containing different cathode metal contacts in the configuration ITO/PEDOT:PSS/MAPbI 3 /PCBM/Metal are fully electrically characterized before and after degradation caused by steady illumination during 4 h that induces a dramatic reduction in power conversion efficiency from values of 12 to 1.8%. We show that a decrease in performance and generation of the S-shape is associated with chemical degradation of the metal contact. Alternatively, use of Cr 2 O 3 /Cr as the contact enhances the stability, but modification of the energetic profile during steady illumination takes place, significantly reducing the performance. Several techniques including capacitance−voltage, X-ray diffraction, and optical absorption results suggest that the properties of the bulk perovskite layer are little affected in the device degradation process. Capacitance−voltage and impedance spectroscopy results show that the electrical properties of the cathode contact are being modified by generation of a dipole at the cathode that causes a large shift of the flat-band potential that modifies the interfacial energy barrier and impedes efficient extraction of electrons. Ionic movement in the perovskite layer changes the energy profile close to the contacts, modifying the energy level stabilization at the cathode. These results provide insights into the degradation mechanisms of perovskite solar cells and highlight the importance to further study the use of protecting layers to avoid the chemical reactivity of the perovskite with the external contacts

Case Report: Identification of a novel LYN::LINC01900 transcript with promyelocytic phenotype and TP53 mutation in acute myeloid leukemia

Acute myeloid leukemia (AML) is a malignant disease of myeloid hematopoietic stem/progenitor cells characterized by the abnormal proliferation of primitive and naive random cells in the bone marrow and peripheral blood. Acute promyelocytic leukemia (APL) is a type (AML-M3) of AML. Most patients with APL have the characteristic chromosomal translocation t(15; 17)(q22; q12), forming PML::RARA fusion. The occurrence and progression of AML are often accompanied by the emergence of gene fusions such as PML::RARA, CBFβ::MYH11, and RUNX1::RUNX1T1, among others. Gene fusions are the main molecular biological abnormalities in acute leukemia, and all fusion genes act as crucial oncogenic factors in leukemia. Herein, we report the first case of LYN::LINC01900 fusion transcript in AML with a promyelocytic phenotype and TP53 mutation. Further studies should address whether new protein products may result from this fusion, as well as the biological function of these new products in disease occurrence and progression

Immune checkpoint inhibitors-related pancreatitis with fulminant type 1 diabetes mellitus: case report and literature review

Immune checkpoint inhibitors (ICIs) are increasingly being used in the treatment of advanced human malignancies. ICIs-related adverse events, including pancreatitis and diabetes, have been individually characterized in the literature. The co-occurrence of ICIs-related pancreatitis with diabetes is rare and easily overlooked, but it is often severe or fatal. We present a patient with renal tumor resection who was treated with injection of the PD-L1 inhibitor toripalimab and eventually developed acute pancreatitis and fulminant type 1 diabetes mellitus. In addition, we conducted a literature review of ICIs-related pancreatitis with diabetes. The case in our report presented with paroxysmal abdominal pain and loss of appetite. Intravenous fluids and insulin infusion improved the patient’s pancreatitis and explosive hyperglycemia. This article suggests that ICIs can affect endocrine and exocrine functions of the pancreas, while providing information and new perspectives for the diagnosis and treatment of this challenging rare disease, helping inspire clinicians for the early identification and effective management of similar cases

Metagenomic insights into the composition and function of the gut microbiota of mice infected with Toxoplasma gondii

IntroductionDespite Toxoplasma gondii infection leading to dysbiosis and enteritis, the function of gut microbiota in toxoplasmosis has not been explored.MethodsHere, shotgun metagenomics was employed to characterize the composition and function of mouse microbial community during acute and chronic T. gondii infection, respectively.ResultsThe results revealed that the diversity of gut bacteria was decreased immediately after T. gondii infection, and was increased with the duration of infection. In addition, T. gondii infection led to gut microbiota dysbiosis both in acute and chronic infection periods. Therein, several signatures, including depression of Firmicutes to Bacteroidetes ratio and infection-enriched Proteobacteria, were observed in the chronic period, which may contribute to aggravated gut inflammation and disease severity. Functional analysis showed that a large amount of Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways and carbohydrate-active enzymes (CAZy) family displayed distinct variation in abundance between infected and healthy mice. The lipopolysaccharide biosynthesis related pathways were activated in the chronic infection period, which might lead to immune system imbalance and involve in intestinal inflammation. Moreover, microbial and functional spectrums were more disordered in chronic than acute infection periods, thus implying gut microbiota was more likely to participate in disease process in the chronically infected mice, even exacerbated immunologic derangement and disease progression.DiscussionOur data indicate that the gut microbiota plays a potentially important role in protecting mice from T. gondii infection, and contributes to better understand the association between gut microbiota and toxoplasmosis

Graphene oxide-based nanomaterials : synthesis, optical characterisation and supercapacitor

This thesis concerns the study of effect of functional groups on graphene oxide (GO). Functional groups strongly affect the optical properties of GO and they can be used to facilitate the preparation of GO derivatives. This thesis systematically investigates the synthesis, optical characterization and applications of GO-based materials, with an emphasis on the influence of the oxygen-containing groups on their chemical and optical properties. The research can be divided into three sections as shown below.First, the identification of the thickness of GO by white light contrast spectroscopy, which is discussed in Chapter 4. This topic has rarely been studied because of the weak optical absorbance that originates from both the large optical gap caused by sp3 hybridization of the functional groups and the adsorbed water on GO sheets. In our work, we have successfully identified the number of layers of GO (≤10 layers) and deduced the complex refractive index of GO sheets (≤10 layers) as nGO = 1.2-0.24i. For GO sheets of a few layers (≤10 layers), both the optical contrast (at ~580 nm) and the G band intensity increase linearly with the thickness. In comparison with Raman spectroscopy, in which laser-induced reduction of GO cannot be absolutely avoided, contrast spectroscopy is a non-destructive and more efficient approach. Simulation results based on Fresnel’s equations agree well with the evolution of the optical contrast and the trend of G band intensity in accordance with the number of layers. The refractive index of GO can be precisely calculated by this method, which can subsequently be used as a basis for further examination of the optical properties of GO. Overall, we proposed a simple and rapid approach to determine the number of layer of GO on the Si/SiO2 substrate by measuring the optical contrast values, which can also be applied to other graphene-based and two-dimensional materials.DOCTOR OF PHILOSOPHY (SPMS

Effect of Shear Deformation on Texture Evolution in Rolled Pure Titanium

The cold rolling texture evolution under different strain states caused by coupled effects from different combinations of roll gap geometry and friction in pure titanium with initial typical recrystallized texture has been studied using viscoplastic self-consistent simulations. Under plane strain state, the texture is dominated by a typical cold rolling fiber texture RD// in pure titanium. However, when shear deformation is induced and increased, RD// fiber texture is decreased, whereas basal texture (0001)[1010] is increased and a strong partial fiber texture RD// is formed. The variation of cold rolling texture at different strain states can be ascribed to variation of relative contribution from activation of prismatic, basal and pyramidal slip

A multi-objective optimization design approach of large mining planetary gear reducer

Abstract A two-stage computational framework is proposed to optimize the radiated noise and weight of a large mining planetary gear reducer under the rated conditions, based on a combination of response surface methodology and multi-objective optimization. The well-established transient dynamic analysis model of a large mining planetary gear reducer, which is used to analyze the mechanical strength and acoustic characteristics of the gear reducer. A unified experimental design is developed to obtain the response surface of the gearbox radiated noise and the mass of the gearbox housing. After obtaining the multi-objective optimization function, the multi-objective optimization problem for a lightweight and low-noise gearbox is performed using non-dominated sorting from the Genetic Algorithm II (NSGA-II). The research results demonstrates the effectiveness of the proposed optimization method in reducing vibrating amplitude and weight of the gearbox. This is crucial for minimizing energy consumption and enhancing the overall performance of the system. Additionally, the optimized gearbox design not only saves energy but also contributes to the reduction of carbon emissions, making it environmentally friendly

Low temperature formation of AlN nanofibers by carbothermal reduction nitridation of hydrothermal precursor fibers

AlN nanofibers were fabricated by carbothermal reduction (CRN) method of hydrothermal precursor fibers using aluminum nitrate, urea, glucose and polyethylene glycol as raw materials. The as-fabricated samples were characterized by TG-DSC, XRD, SEM, EDS, and UV–vis absorption and PL spectra. The results indicated that raw materials were transformed to NH4Al[(OOH)HCO3] (AACH) fibers in hydrothermal process, carbon coated γ-Al2O3 fibers in decomposition process, and AlN nanofibers in CRN process. In relation to other CRN methods, the hydrothermal precursors reduced the fabrication temperature in 200 °C. The diameter of the AlN nanofibers fabricated at 1400 °C was 90–110 nm with several micrometers length. These fibers showed broad absorption band from 190 to 230 nm with an absorption edge at 198 nm and obvious emission at approximately 478 nm and 577 nm excited by 350 nm, indicating a valuable application in light-emitting nanodevices. Such a strategy can be extended to synthesize other nitride fibers