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Since their discovery in 19601, metallic glasses based on a wide range of elements have been developed2. However, the theoretical prediction of glass-forming compositions is challenging and the discovery of alloys with specific properties has so far largely been the result of trial and error3-8. Bulk metallic glasses can exhibit strength and elasticity surpassing those of conventional structural alloys9-11, but the mechanical properties of these glasses are critically dependent on the glass transition temperature. At temperatures approaching the glass transition, bulk metallic glasses undergo plastic flow, resulting in a substantial decrease in quasi-static strength. Bulk metallic glasses with glass transition temperatures greater than 1,000 kelvin have been developed, but the supercooled liquid region (between the glass transition and the crystallization temperature) is narrow, resulting in very little thermoplastic formability, which limits their practical applicability. Here we report the design of iridium/nickel/tantalum metallic glasses (and others also containing boron) with a glass transition temperature of up to 1,162 kelvin and a supercooled liquid region of 136 kelvin that is wider than that of most existing metallic glasses12. Our Ir-Ni-Ta-(B) glasses exhibit high strength at high temperatures compared to existing alloys: 3.7 gigapascals at 1,000 kelvin9,13. Their glass-forming ability is characterized by a critical casting thickness of three millimetres, suggesting that small-scale components for applications at high temperatures or in harsh environments can readily be obtained by thermoplastic forming14. To identify alloys of interest, we used a simplified combinatorial approach6-8 harnessing a previously reported correlation between glass-forming ability and electrical resistivity15-17. This method is non-destructive, allowing subsequent testing of a range of physical properties on the same library of samples. The practicality of our design and discovery approach, exemplified by the identification of high-strength, high-temperature bulk metallic glasses, bodes well for enabling the discovery of other glassy alloys with exciting properties.
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Circular RNA (circRNA) is thought to mediate the occurrence and development of human cancer and usually acts as a tiny RNA (miRNA) sponge to regulate downstream gene expression. However, it is not clear whether and how circACVR2A (hsa_circ_0001073) is involved in the progression of HCC. The purpose of this study is to clarify the potential role and molecular mechanism of circACVR2A in regulating the progression of hepatocellular carcinoma cells (HCC). The abundance of related proteins in circACVR2A, microRNA (miR511-5p) and PI3K-Akt signaling pathway was determined by quantitative reverse transcriptase polymerase chain reaction (RT-PCR) or Western blotting. Cell viability, invasion and apoptosis were analyzed by CCK-8, Transwell analysis and Tunel staining, respectively. The interaction between circACVR2A and microRNA was evaluated by double luciferase reporter gene assay. The results showed that circACVR2A was highly expressed in hepatocellular carcinoma cell lines. Our in vivo and in vitro data showed that circACVR2A promoted the proliferation, migration and invasion of HCC. In terms of mechanism, we found that circACVR2A can directly interact with miR511-5p and act as a miRNA sponge to regulate the expression of related proteins in PI3K-Akt signaling pathway.In HCC, circACVR2A can mediate miR-511-5p/mRNA network to activate PI3K signal pathway. This shows that the molecular regulatory network with circACVR2A as the core is a new potential target for diagnosis and treatment of hepatocellular carcinoma.
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Carcinoma Hepatocelular , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas , MicroRNAs , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , RNA Circular , Transdução de Sinais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , MicroRNAs/genética , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , RNA Circular/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Movimento Celular/genética , Animais , Linhagem Celular Tumoral , Camundongos , Apoptose/genética , Progressão da Doença , MasculinoRESUMO
BACKGROUND: Cervicovaginal microbiome plays an important role in the persistence of HPV infection and subsequent disease development. However, cervicovaginal microbiota varied cross populations with different habits and regions. Identification of population-specific biomarkers from cervicovaginal microbiota and host metabolome axis may support early detection or surveillance of HPV-induced cervical disease at all sites. Therefore, in the present study, to identify HPV-specific biomarkers, cervicovaginal secretion and serum samples from HPV-infected patients (HPV group, n = 25) and normal controls (normal group, n = 17) in Xichang, China were collected for microbiome (16S rRNA gene sequencing) and metabolome (UHPLC-MS/MS) analysis, respectively. RESULTS: The results showed that key altered metabolites of 9,10-DiHOME, α-linolenic acid, ethylparaben, glycocholic acid, pipecolic acid, and 9,12,13-trihydroxy-10(E),15(Z)-octadecadienoic acid, correlating with Sneathia (Sneathia_amnii), Lactobacillus (Lactobacillus_iners), Atopobium, Mycoplasma, and Gardnerella, may be potential biomarkers of HPV infection. CONCLUSION: The results of current study would help to reveal the association of changes in cervicovaginal microbiota and serum metabolome with HPV infections.
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Microbiota , Infecções por Papillomavirus , Feminino , Humanos , Vagina , RNA Ribossômico 16S/genética , Espectrometria de Massas em Tandem , Metaboloma , Microbiota/genética , Biomarcadores/metabolismoRESUMO
Lanthanide-doped upconversion (UC) materials have been extensively investigated for their unique capability to convert low-energy excitation into high-energy emission. Contrary to previous reports suggesting that efficient UC luminescence (UCL) is exclusively observed in materials with a wide bandgap, we have discovered in this study that Y2Mo4O15:Yb3+/Tm3+ microcrystals, a narrowband material, exhibit highly efficient UC emission. Remarkably, these microcrystals do not display any four- or five-photon UC emission bands. This particular optical phenomenon is independent of the variation in doping ion concentration, temperature, phonon energy, and excitation power density. Combining theoretical calculations and experimental results, we attribute the vanishing emission bands to the strong interaction between the bandgap of the Y2Mo4O15 host matrix (3.37â eV) and the high-energy levels (1I6 and 1D2) of Tm3+ ions. This interaction can effectively catalyze the UC emission process of Tm3+ ions, which leads to Y2Mo4O15:Yb3+/Tm3+ microcrystals possessing very strong UCL intensity. The brightness of these microcrystals outshines commercial UC NaYF4:Yb3+,Er3+ green phosphors by a factor of 10 and is 1.4 times greater than that of UC NaYF4:Yb3+,Tm3+ blue phosphors. Ultimately, Y2Mo4O15:Yb3+/Tm3+ microcrystals, with their distinctive optical characteristics, are being tailored for sophisticated anti-counterfeiting and information encryption applications.
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Upconversion (UC) materials are renowned for their ability to convert low-energy photons into high-energy ones. The manipulation of parameters allows for the observation of multicolored UC luminescence (UCL) within a single material system. While modulation of multicolored UCL commonly relies on excitation at approximately 980â nm, investigation into multicolored UC materials activated by a 1532â nm excitation source remains comparatively scarce. In this work, we introduce NaLnF4:Er3+ as a novel class of smart luminescent materials. When the power density of a 1532â nm laser increases from 0.5 to 20.0â W/cm2, the emission peak positions remain unchanged, but the red-to-green (R/G) ratio decreases significantly from 18.82 to 1.48, inducing a color shift from red to yellow and ultimately to green. In contrast, no color variation is observed when NaLnF4:Er3+ is excited with a 980â nm laser at different power densities. This power-dependent multicolored UCL of NaLnF4:Er3+ excited at 1532â nm can be attributed to the competitive processes of upward pumping and downward relaxation of electrons on the 4I9/2 level of Er3+. By utilizing the unique UC characteristics of NaLnF4:Er3+, its potential utility in anti-counterfeiting applications is demonstrated. Our research highlights the distinctive optical properties of NaLnF4:Er3+ and provides novel insights into the use of luminescent materials in optical anti-counterfeiting technologies.
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Hypoxia-induced vasoconstriction and vascular remodelling are the main pathological features of hypoxic pulmonary arterial hypertension (HPAH), and inflammation is participated in the occurrence of pulmonary vascular remodelling (PVR). Matrine is an alkaloid with the effects of anti-inflammation, antifibrosis and antitumour. But, few studies have explored the role of matrine in regulating PVR, and the related mechanisms are still unknown. In this study, we found that hypoxia-induced pulmonary artery smooth muscle cells (PASMCs) proliferation and inhibited its apoptosis, reduced the expression of ribosomal protein s5 and activated the nuclear factor kappa-B (NF-κB) signalling. Matrine, sildenafil and NF-κB inhibitor Bay 11-7082 could reverse these changes and impel the cell cycle in phase S retardation, and reduced the expression of p50, p65, proliferating cell nuclear antigen (PCNA), Bcl-2. In addition, matrine could lower right ventricular systolic pressure and mean pulmonary artery pressure of rats, α-smooth muscle actin and PCNA expression in pulmonary artery media, the levels of tumor necrosis factor-α and interleuki-1ß, thus improved hypoxia-induced PVR. This study indicated that matrine could alleviate inflammation and improve PVR through reversing the imbalance of proliferation and apoptosis of PASMCs, thus it had a therapeutic effect on HPAH.
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Hidralazina/análogos & derivados , Hipertensão Pulmonar , NF-kappa B , Ratos , Animais , NF-kappa B/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Matrinas , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/patologia , Remodelação Vascular , Proliferação de Células , Hipóxia/complicações , Hipóxia/metabolismo , Inflamação/metabolismo , Miócitos de Músculo Liso/metabolismo , HidrazonasRESUMO
Macrophages, crucial components of the human immune system, can be polarized into M1/M2 phenotypes, each with distinct functions and roles. Macrophage polarization has been reported to be significantly involved in the inflammation and fibrosis observed in kidney injury. MicroRNA (miRNA), a type of short RNA lacking protein-coding function, can inhibit specific mRNA by partially binding to its target mRNA. The intricate association between miRNAs and macrophages has been attracting increasing interest in recent years. This review discusses the role of miRNAs in regulating macrophage-mediated kidney injury. It shows how miRNAs can influence macrophage polarization, thereby altering the biological function of macrophages in the kidney. Furthermore, this review highlights the significance of miRNAs derived from exosomes and extracellular vesicles as a crucial mediator in the crosstalk between macrophages and kidney cells. The potential of miRNAs as treatment applications and biomarkers for macrophage-mediated kidney injury is also discussed.
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Zinc tungstate is a semiconductor known for its favorable photocatalytic, photoluminescence, and scintillation properties, coupled with its relatively low cost, reduced toxicity, and high stability in biological and catalytic environments. In particular, zinc tungstate evinces scintillation properties, namely the ability to emit visible light upon absorption of energetic radiation such as x rays, which has led to applications not only as radiation detectors but also for biomedical applications involving the delivery of optical light to deep tissue, such as photodynamic therapy and optogenetics. Here, we report on the synthesis of zinc tungstate nanorods generated via an optimized but facile method, which allows for synthetic control over the aspect ratio of the as-synthesized anisotropic motifs via rational variation of the solution pH. We investigate the effect of aspect ratio on their resulting photoluminescent and radioluminescent properties. We further demonstrate the potential of these zinc tungstate nanorods for biomedical applications, such as photodynamic therapy for cancer treatment, by analyzing their toxicological profile within cell lines and neurons.
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Nanotubos , Compostos de Tungstênio , Compostos de Tungstênio/química , Compostos de Tungstênio/toxicidade , Nanotubos/química , Humanos , Animais , Fotoquimioterapia , Sobrevivência Celular/efeitos dos fármacos , Compostos de Zinco/química , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Zinco/químicaRESUMO
BACKGROUND: As a non-competitive N-methyl d-aspartate receptor antagonist, ketamine exerts rapid-onset and long-lasting antidepressant effects on depression, but some side effects limit its use. To identify a safer compound that may provide similar antidepressant effects, here we investigated whether CP-101,606, a selective NR2B receptor inhibitor, provides similar antidepressant effects and explored its underlying mechanisms. METHODS: To mimic depressive-like behavior, mice were subjected to chronic unpredictable mild stress (CUMS) for 21â¯days. Mice were treated with CP-101,606 at 10, 20, and 40â¯mg/kg doses for 7, 14, and 21â¯days, respectively, followed by a sucrose preference test (SPT), tail suspension test (TST), and forced swimming test (FST). Western blot analysis was performed on several targets (mTOR, p-mTOR, p70S6K, p-p70S6K, PSD-95, and GluA1), along with immunohistochemistry (GluA1) and immunofluorescence (p-mTOR) assays, using hippocampal tissue. RESULTS: CP-101,606 at 20 and 40â¯mg/kg doses for 7 and 14â¯days and fluoxetine 10â¯mg/kg and CP-101606 20â¯mg/kg for 21â¯days ameliorated depression-like behaviors in the SPT, TST, and FST. The effects of CP-101,606 were associated with a reversal of the CUMS-induced decrease in mTOR (Ser2448) and p70S6K (Thr389) phosphorylation and increasing PSD95 and GluA1 synthesis in the hippocampus. CONCLUSIONS: Our results demonstrate that CP-101,606 produces antidepressant effects in CUMS mice, which may be mediated by mTOR signaling cascade upregulation. Our findings suggest the possible utility of CP-101,606 as a treatment for depression.
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Depressão , Proteínas Quinases S6 Ribossômicas 70-kDa , Camundongos , Animais , Depressão/tratamento farmacológico , Depressão/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/farmacologia , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Antidepressivos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Estresse Psicológico/metabolismo , Hipocampo/metabolismo , Modelos Animais de DoençasRESUMO
BACKGROUND: Pakistani's health services delivery system has been rarely evaluated regarding patient satisfaction. This study examined the performance of the Pakistani health system from the perspective of doctor services (DS), digital payment system (DPS), nurses' services (NS), laboratory services (LS), pharmacy services (PHS), registration services (RS), physical services (environmentally and tangible) and doctor-patient communication (DPC) about patient satisfaction. A random sampling technique was adopted for data collection. METHODOLOGY: The Social Science Statistical Package (SPSS), analysis of moment structures (AMOS), and structural equation modeling were used to analyze the data for reliability, validity, correlations, and descriptive findings. The 879 responses were used for study analysis. RESULTS: The study revealed that patient satisfaction was found to be significantly affected positively by LS, PHS, DS, NS, and DPS, while DPC, RS, and PF were impacted non-significantly. Consequently, there is a considerable communication gap in the doctor-patient interaction, and Pakistan's healthcare system is confronted with a shortage of physical infrastructure and challenges in the digital system. CONCLUSION: Furthermore, the insufficient emphasis on registration services necessitates immediate action to improve the entire patient experience and satisfaction. Identifying these shortcomings has the potential to result in a healthcare system that is more efficient and focused on the needs of the patients.
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Atenção à Saúde , Satisfação do Paciente , Relações Médico-Paciente , Humanos , Paquistão , Masculino , Feminino , Adulto , Comunicação , Inquéritos e Questionários , Pessoa de Meia-Idade , Hospitais , Adulto Jovem , Reprodutibilidade dos TestesRESUMO
Antimicrobial resistance (AMR) emerges as a severe crisis to public health and requires global action. The occurrence of bacterial pathogens with multi-drug resistance appeals to exploring alternative therapeutic strategies. Antivirulence treatment has been a positive substitute in seeking to circumvent AMR, which aims to target virulence factors directly to combat bacterial infections. Accumulated evidence suggests that plant-derived natural products, which have been utilized to treat infectious diseases for centuries, can be abundant sources for screening potential virulence-arresting drugs (VADs) to develop advanced therapeutics for infectious diseases. This review sums up some virulence factors and their actions in various species of bacteria, as well as recent advances pertaining to plant-derived natural products as VAD candidates. Furthermore, we also discuss natural VAD-related clinical trials and patents, the perspective of VAD-based advanced therapeutics for infectious diseases and critical challenges hampering clinical use of VADs, and genomics-guided identification for VAD therapeutic. These newly discovered natural VADs will be encouraging and optimistic candidates that may sustainably combat AMR.
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Anti-Infecciosos , Produtos Biológicos , Doenças Transmissíveis , Humanos , Virulência , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/farmacologia , Anti-Infecciosos/uso terapêutico , Bactérias , Fatores de Virulência , Doenças Transmissíveis/tratamento farmacológico , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêuticoRESUMO
INTRODUCTION: Liuweizhiji Gegen-Sangshen (LGS) oral liquid is a Chinese patent medicine that is widely used for the prevention and treatment of alcoholic liver disease in clinical practice. However, the chemical complexity of LGS has not yet been investigated. OBJECTIVE: The aim of this study was to rapidly identify chemical constituents of LGS and establish a quality control method based on fingerprint and quantitative analysis. METHODOLOGY: A comprehensive strategy was used by combining qualitative analysis by ultra-performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and fingerprint analysis by high-performance liquid chromatography with diode array detection (HPLC-DAD). RESULTS: A total of 162 chemical components in LGS, including 91 flavonoids, 31 organic acids, and 20 phenolic compounds, were identified or preliminarily characterized in both positive and negative ion modes based on the UPLC-Q-TOF-MS results. Of these, 37 were confirmed with the reference standards. In fingerprint analysis, 23 peaks were chosen as common peaks and used to evaluate the similarity of different batches of LGS. Subsequently, a rapid quantification method was optimized and validated for the simultaneous determination of multiple chemical markers in LGS. The validated quantitative method was successfully used to analyze different batches of LGS samples. CONCLUSION: The proposed comprehensive strategy combining HPLC-DAD fingerprinting and multi-component quantification demonstrated satisfactory results with high efficiency, accuracy, and reliability. This can be used as a reference for the overall quality consistency evaluation of Chinese patent medicines.
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Medicamentos de Ervas Chinesas , Controle de Qualidade , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/análise , Flavonoides/análise , Espectrometria de Massas/métodos , Reprodutibilidade dos Testes , Administração Oral , Fenóis/análiseRESUMO
OBJECTIVES: We aimed to evaluate the changes in renal cortical microperfusion and quantitative contrast-enhanced ultrasonography (CEUS) parameters after kidney transplantation, and to determine the evidence-based value of CEUS in predicting renal dysfunction. METHODS: The Embase, MEDLINE, Web of Science, and Cochrane Library databases were searched for relevant studies published from 2000 to 2023 on the use of CEUS to assess the renal cortical microcirculation after kidney transplantation. Subject terms and related keywords were combined, and a meta-analysis and systematic review were performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. RESULTS: The search yielded six studies involving 451 patients with moderate to high overall quality. The peak intensity (standardized mean difference [SMD]: -0.64, 95% confidence interval [CI] -1.13 to -0.15, p = 0.01) of CEUS was significantly lower in patients with renal dysfunction than in those with stable renal function. However, the time to peak (SMD: 0.28, 95% CI 0.04 to 0.52, p = 0.02) was significantly shorter in patients with renal dysfunction than in those with stable renal function. The total renal cortical microperfusion and renal cortical perfusion intensity were decreased, and the perfusion time was prolonged, in patients with renal dysfunction after kidney transplantation. CONCLUSION: CEUS parameters can reflect real-time changes in renal cortical microperfusion, thus providing a basis for the early diagnosis of renal dysfunction after kidney transplantation.
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The metastable liquid properties and chemical bonds beyond 2000â K remain a huge challenge for ground-based research on liquid materials chemistry. We show the strong undercooling capability, metastable liquid properties and surface wave patterns of refractory Nb-Si and Zr-V binary alloys explored in space environment. The floating droplet of Nb82.7Si17.3 eutectic alloy superheated up to 2338â K exhibited an extreme undercooling of 437â K, approaching the 0.2TE threshold for homogeneous nucleation of liquid-solid reaction. The microgravity state endowed alloy droplets with nearly perfect sphericity and thus ensured the high accuracy to determine metastable undercooled liquid properties. A special kind of swirling flow was induced for liquid alloy owing to Marangoni convection, which resulted in the spiral microstructures on Zr64V36 alloy surface during liquid-solid phase transition. The coupled impacts of surface nucleation and surface flow brought in a novel olivary shape for these binary alloys. Furthermore, the chemical bonds and atomic structures of high temperature liquids were revealed to understand the liquid properties in outer space circumstances.
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BACKGROUND: Diabetes-related limb ischemia is a challenge for lower extremity amputation. Aurora Kinase A (AURKA) is an essential serine/threonine kinase for mitosis, while its role in limb ischemia remains unclear. METHOD: Human microvascular endothelial cells (HMEC-1) were cultured in high glucose (HG, 25 mmol/L D-glucose) and no additional growth factors (ND) medium to mimic diabetes and low growth factors deprivation as in vitro model. Diabetic C57BL/6 mice were induced by streptozotocin (STZ) administration. After seven days, ischemia was surgically performed by left unilateral femoral artery ligation on diabetic mice. The vector of adenovirus was utilized to overexpress AURKA in vitro and in vivo. RESULTS: In our study, HG and ND-mediated downregulation of AURKA impaired the cell cycle progression, proliferation, migration, and tube formation ability of HMEC-1, which were rescued by overexpressed AURKA. Increased expression of vascular endothelial growth factor A (VEGFA) induced by overexpressed AURKA were likely regulatory molecules that coordinate these events. Mice with AURKA overexpression exhibited improved angiogenesis in response to VEGF in Matrigel plug assay, with increased capillary density and hemoglobin content. In diabetic limb ischemia mice, AURKA overexpression rescued blood perfusion and motor deficits, accompanied by the recovery of gastrocnemius muscles observed by H&E staining and positive Desmin staining. Moreover, AURKA overexpression rescued diabetes-related impairment of angiogenesis, arteriogenesis, and functional recovery in the ischemic limb. Signal pathway results revealed that VEGFR2/PI3K/AKT pathway might be involved in AURKA triggered angiogenesis procedure. In addition, AURKA overexpression impeded oxidative stress and subsequent following lipid peroxidation both in vitro and in vivo, indicating another protective mechanism of AURKA function in diabetic limb ischemia. The changes in lipid peroxidation biomarkers (lipid ROS, GPX4, SLC7A11, ALOX5, and ASLC4) in in vitro and in vivo were suggestive of the possible involvement of ferroptosis and interaction between AUKRA and ferroptosis in diabetic limb ischemia, which need further investigation. CONCLUSIONS: These results implicated a potent role of AURKA in diabetes-related impairment of ischemia-mediated angiogenesis and implied a potential therapeutic target for ischemic diseases of diabetes.
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Diabetes Mellitus Experimental , Fator A de Crescimento do Endotélio Vascular , Humanos , Camundongos , Animais , Fator A de Crescimento do Endotélio Vascular/metabolismo , Aurora Quinase A/metabolismo , Aurora Quinase A/uso terapêutico , Diabetes Mellitus Experimental/metabolismo , Células Endoteliais/metabolismo , Neovascularização Fisiológica , Fosfatidilinositol 3-Quinases/metabolismo , Membro Posterior , Camundongos Endogâmicos C57BL , Isquemia , Músculo Esquelético/metabolismoRESUMO
Given that it is closely related to perovskite crystallization and interfacial trap densities, buried interfacial engineering is crucial for creating effective and stable perovskite solar cells. Compared with the in-depth studies on the defect at the top perovskite interface, exploring the defect of the buried side of perovskite film is relatively complicated and scanty owing to the non-exposed feature. Herein, the degradation process is probed from the buried side of perovskite films with continuous illumination and its effects on morphology and photoelectronic characteristics with a facile lift-off method. Additionally, a buffer layer of Piperazine Dihydriodide (PDI2 ) is inserted into the imbedded bottom interface. The PDI2 buffer layer is able to lubricate the mismatched thermal expansion between perovskite and substrate, resulting in the release of lattice strain and thus a void-free buried interface. With the PDI2 buffer layer, the degradation originates from the growing voids and increasing non-radiative recombination at the imbedded bottom interfaces are suppressed effectively, leading to prolonged operation lifetime of the perovskite solar cells. As a result, the power conversion efficiency of an optimized p-i-n inverted photovoltaic device reaches 23.47% (with certified 23.42%) and the unencapsulated devices maintain 90.27% of initial efficiency after 800 h continuous light soaking.
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Controlling crystallization and grain growth is crucial for realizing highly efficient hybrid perovskite solar cells (PSCs). In this work, enhanced PSC photovoltaic performance and stability by accelerating perovskite crystallization and grain growth via 2D hexagonal boron nitride (hBN) nanosheet additives incorporated into the active perovskite layer are demonstrated. In situ X-ray scattering and infrared thermal imaging during the perovskite annealing process revealed the highly thermally conductive hBN nanosheets promoted the phase conversion and grain growth in the perovskite layer by facilitating a more rapid and spatially uniform temperature rise within the perovskite film. Complementary structural, physicochemical, and electrical characterizations further showed that the hBN nanosheets formed a physical barrier at the perovskite grain boundaries and the interfaces with charge transport layers, passivating defects, and retarding ion migration. As a result, the power conversion efficiency of the PSC is improved from 17.4% to 19.8%, along with enhanced device stability, retaining ≈90% of the initial efficiency even after 500 h ambient air storage. The results not only highlight 2D hBN as an effective additive for PSCs but also suggest enhanced thermal transport as one of the pathways for improved PSC performance by 2D material additives in general.
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Despite the importance of glass forming ability as a major alloy characteristic, it is poorly understood and its quantification has been experimentally laborious and computationally challenging. Here, we uncover that the glass forming ability of an alloy is represented in its amorphous structure far away from equilibrium, which can be exposed by conventional X-ray diffraction. Specifically, we fabricated roughly 5,700 alloys from 12 alloy systems and characterized the full-width at half-maximum, Δq, of the first diffraction peak in the X-ray diffraction pattern. A strong correlation between high glass forming ability and a large Δq was found. This correlation indicates that a large dispersion of structural units comprising the amorphous structure is the universal indicator for high metallic glass formation. When paired with combinatorial synthesis, the correlation enhances throughput by up to 100 times compared to today's state-of-the-art combinatorial methods and will facilitate the discovery of bulk metallic glasses.
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Ligas , Vidro , Ligas/química , Vidro/química , Difração de Raios XRESUMO
Advanced hybrid materials have attracted extensive attention in optoelectronics and photonics application due to their unique and excellent properties. Here, the multicolor upconversion luminescence properties of the hybrid materials composed of CsPbX3(X = Br/I) perovskite quantum dots and upconversion nanoparticles (UCNPs, core-shell NaYF4:25%Yb3+,0.5%Tm3+@NaYF4) is reported, achieving the upconversion luminescence with stable and bright of CsPbX3 perovskite quantum dots under 980 nm excitation. Compared with the nonlinear upconversion of multi-photon absorption in perovskite, UCNPs/CsPbX3 achieves lower power density excitation by using the UCNPs as the physical energy transfer level, meeting the demand for multi-color upconversion luminescence in optical applications. Also, the UCNPs/CsPbX3 combined with ultraviolet curable resin (UVCR) shows excellent water and air stability, which can be employed as multicolor fluorescent ink for screen printing security labels. Through the conversion strategy, the message of the security labels can be encrypted and decrypted by using UV light and a 980 nm continuous wave excitation laser as a switch, which greatly improves the difficulty of forgery. These findings provide a general method to stimulate photon upconversion and improve the stability of perovskite nanocrystals, which will be better applied in the field of anti-counterfeiting.
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Metal-organic frameworks (MOFs) are a class of highly porous materials that have garnered significant attention in the field of optoelectronics due to their exceptional properties. In this study, CsPbBr2Cl@EuMOFs nanocomposites were synthesized using a two-step method. The fluorescence evolution of the CsPbBr2Cl@EuMOFs was investigated under high pressure, revealing a synergistic luminescence effect between CsPbBr2Cl and Eu3+. The study found that the synergistic luminescence of CsPbBr2Cl@EuMOFs remains stable even under high pressure, and there is no energy transfer among different luminous centers. These findings provide a meaningful case for future research on nanocomposites with multiple luminescent centers. Additionally, CsPbBr2Cl@EuMOFs exhibit a sensitive color-changing mechanism under high pressure, making them a promising candidate for pressure calibration via the color change of the MOF materials.