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Recent advances in space missions have motivated increased research into photovoltaic technologies with improved tolerance to radiation environments in space. Here, we evaluate proton radiation resilience in perovskite solar cells via an employment of a vanadium (V) oxide (V2Ox)/self‐assembled layer (SAM) bilayer hole transport layers (HTLs). We show that the V2Ox/SAM bi‐HTL initially promotes more efficient charge extraction, as evidenced by enhanced photoluminescence quenching, while higher proton irradiation doses progressively weaken this benefit, consistent with the irradiation‐driven interfacial modification rather than significant absorber degradation. Notably, X‐ray photoelectron spectroscopy reveals irradiation‐induced reduction of V2Ox, with oxygen vacancy formation and increased V4+ content, indicating a redox‐active interface that promotes hole extraction while buffering proton‐induced interfacial degradation. In addition, analysis of the Pb core level reveals that SAM‐only devices exhibit the emergence and growth of metallic Pb species after proton irradiation, whereas devices incorporating V2Ox act as a redox buffer that suppress metallic Pb formation across proton irradiations. This work first demonstrates the effects of metal oxide charge transport layer engineering on radiation‐hardened perovskite interfaces and advances the development of durable, lightweight photovoltaic technologies for space power applications. A redox‐active V2Ox/self‐assembled layer bilayer hole transport layer improves the proton radiation resilience of perovskite solar cells for space applications. The V2Ox interface suppresses irradiation‐induced metallic Pb formation while buffering interfacial degradation, highlighting metal oxide interfacial engineering as a practical route toward durable lightweight space photovoltaics.

The terahertz (THz)-wave absorption properties in organic-inorganic hybrid perovskite (OHP) materials are investigated with the in-depth development of OHP-based THz applications. In the THz range from 0.5 to 3 THz, OHPs typically show several interesting phonon modes such as transverse, longitudinal, and halogen self-vibrations. To modulate these frequencies, the density changes in defect-incorporated structures and element mixtures were tested and confirmed. In the literature, the origin of phonon modes in OHP materials have been mostly explained. However, we found new phonon vibration modes in formamidinium (FA)-based hybrid perovskite structures. FAPbI3 single crystals, organic–inorganic hybrid perovskites, of the δ-, δ/α-mixed-, and α-phases were prepared. We intriguingly found that the δ/α-mixed-phase exhibited significant THz-wave absorption peaks at 2.0 and 2.2 THz that were not related to any phonon modes from either the δ- or α-phases, although the δ/α-mixed-phase sample was confirmed to be formed by a physical combination of the δ- and α-phases without the creation of any new chemical states. Our theoretical study performed with ab initio calculations provides an explanation for these unusual THz-wave absorption behaviors; they originate from the novel vibration modes excited at the seamless interfaces in the mixed phase of FAPbI3.We found new phonon vibration modes in formamidinium (FA)-based hybrid perovskite structures. We intriguingly found that the δ/α-mixed-phase exhibited significant THz-wave absorption peaks at 2.0 and 2.2 THz that were not related to any phonon modes from either the δ- or α-phases, although the δ/α-mixed-phase sample was confirmed to be formed by a physical combination of the δ- and α-phases without the creation of any new chemical states. From the theoretical study, they originate from the novel vibration modes excited at the seamless interfaces in the mixed phase of FAPbI3.

Recent advances in space missions have motivated increased research into photovoltaic technologies with improved tolerance to radiation environments in space. Here, we evaluate proton radiation resilience in perovskite solar cells via an employment of a vanadium (V) oxide (V2O x )/self-assembled layer (SAM) bilayer hole transport layers (HTLs). We show that the V2O x /SAM bi-HTL initially promotes more efficient charge extraction, as evidenced by enhanced photoluminescence quenching, while higher proton irradiation doses progressively weaken this benefit, consistent with the irradiation-driven interfacial modification rather than significant absorber degradation. Notably, X-ray photoelectron spectroscopy reveals irradiation-induced reduction of V2O x , with oxygen vacancy formation and increased V4+ content, indicating a redox-active interface that promotes hole extraction while buffering proton-induced interfacial degradation. In addition, analysis of the Pb core level reveals that SAM-only devices exhibit the emergence and growth of metallic Pb species after proton irradiation, whereas devices incorporating V2O x act as a redox buffer that suppress metallic Pb formation across proton irradiations. This work first demonstrates the effects of metal oxide charge transport layer engineering on radiation-hardened perovskite interfaces and advances the development of durable, lightweight photovoltaic technologies for space power applications.Recent advances in space missions have motivated increased research into photovoltaic technologies with improved tolerance to radiation environments in space. Here, we evaluate proton radiation resilience in perovskite solar cells via an employment of a vanadium (V) oxide (V2O x )/self-assembled layer (SAM) bilayer hole transport layers (HTLs). We show that the V2O x /SAM bi-HTL initially promotes more efficient charge extraction, as evidenced by enhanced photoluminescence quenching, while higher proton irradiation doses progressively weaken this benefit, consistent with the irradiation-driven interfacial modification rather than significant absorber degradation. Notably, X-ray photoelectron spectroscopy reveals irradiation-induced reduction of V2O x , with oxygen vacancy formation and increased V4+ content, indicating a redox-active interface that promotes hole extraction while buffering proton-induced interfacial degradation. In addition, analysis of the Pb core level reveals that SAM-only devices exhibit the emergence and growth of metallic Pb species after proton irradiation, whereas devices incorporating V2O x act as a redox buffer that suppress metallic Pb formation across proton irradiations. This work first demonstrates the effects of metal oxide charge transport layer engineering on radiation-hardened perovskite interfaces and advances the development of durable, lightweight photovoltaic technologies for space power applications.

Recent advances in space missions have motivated increased research into photovoltaic technologies with improved tolerance to radiation environments in space. Here, we evaluate proton radiation resilience in perovskite solar cells via an employment of a vanadium (V) oxide (V O )/self-assembled layer (SAM) bilayer hole transport layers (HTLs). We show that the V O /SAM bi-HTL initially promotes more efficient charge extraction, as evidenced by enhanced photoluminescence quenching, while higher proton irradiation doses progressively weaken this benefit, consistent with the irradiation-driven interfacial modification rather than significant absorber degradation. Notably, X-ray photoelectron spectroscopy reveals irradiation-induced reduction of V O , with oxygen vacancy formation and increased V content, indicating a redox-active interface that promotes hole extraction while buffering proton-induced interfacial degradation. In addition, analysis of the Pb core level reveals that SAM-only devices exhibit the emergence and growth of metallic Pb species after proton irradiation, whereas devices incorporating V O act as a redox buffer that suppress metallic Pb formation across proton irradiations. This work first demonstrates the effects of metal oxide charge transport layer engineering on radiation-hardened perovskite interfaces and advances the development of durable, lightweight photovoltaic technologies for space power applications.

This paper reviews the current understanding of the mechanisms of stress corrosion cracking of pipeline steels. The similarities, the differences and the influencing factors are considered for the “high pH” stress corrosion cracking caused by a concentrated bicarbonate-carbonate solution, and for the “low pH” stress corrosion cracking due to a diluter solution. For high pH stress corrosion cracking, it is well accepted that the mechanism involves anodic dissolution for crack initiation and propagation. In contrast, it has been suggested that the low pH stress corrosion cracking is associated with the dissolution of the crack tip and sides, accompanied by the ingress of hydrogen into the pipeline steel. But the precise influence of hydrogen on the mechanism needs to be further studied.

Hepatocellular carcinoma (HCC) is an aggressive malignancy and a major cause of cancer-related mortality worldwide. Our previous study shows that chemokine (C-X-C motif) ligand 1 (CXCL1) was upregulated and CXCR1 was downregulated in tumor tissues as compared to peritumor tissues by chemotaxis assay. As the status of CXCL subgroups and their receptors affect progression of HCC, we evaluated potential mechanisms of CXCL1 associated with anticancer effects in HCC based on our previous study. The effects of targeting CXCL1 by RNA interference (RNAi) on the proliferation and apoptosis of CBRH-7919 cells were observed in vitro and in vivo. Additionally, whether CXCL1 knockdown significantly reduce the activity of STAT3, NF-κB and HIF-1 or not were also estimated. RNAi of CXCL1 in the CBRH-7919 cells decreased the growth of tumors in nude mice by inhibited cells proliferation and induced apoptosis. In conclusion, these findings suggest that CXCL1 plays critical roles in the growth and apoptosis of HCC. RNAi of CXCL1 inhibits the growth and apoptosis of tumor cells, which indicates that CXCL1 may be a potential molecular target for use in HCC therapy.

In the present study, the mechanical properties of Fe processed via severe plastic deformation (equal-channel angular pressing (ECAP)) at room temperature were investigated for the first time. The grain size of annealed Fe, with an initial grain size of about 200 (mu)m, was reduced drastically during ECAP. After eight passes, the grain size reaches 200 to 400 nm, as documented by means of transmission electron microscopy (TEM). The value of microhardness during pressing increases 3 times over that of the starting material after the first pass and increases slightly during subsequent pressing for higher-purity Fe. Examination of the value of microhardness after eight passes as a function of post-ECAP annealing temperature shows a transition from recovery to recrystallization, an observation that resembles the behavior reported for heavily deformed metals and alloys. The tensile and compression behaviors were examined. In tension, a drop in the engineering stress-engineering strain curve beyond maximum load was observed both in the annealed Fe and the ECAP Fe. This drop is related to the neck deformation. The fracture surface, examined by scanning electron microscopy (SEM), shows vein patterns, which is different from the dimples found on the fracture surface of annealed Fe. In compression, an initial strain-hardening region followed by a no-strain-hardening region was observed in the ECAP Fe. The yield strength in tension of the ECAP Fe was observed to be higher than that in compression. The strengthening mechanisms and softening behavior are discussed.

This study was designed to examine respiratory control in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS), with or without CO2 retention. We recruited 10 body mass index-matched, apnea-hypopnea index-matched, age-matched, and lung function-matched OSAHS patients, according to their awake Paco2. Five patients were hypercapnic (Paco2, ≥ 45 mm Hg), and five patients were eucapnic. Hypoxic responses (the ratio of the change in minute ventilation [Δ V˙e] to the change in arterial oxygen saturation[ΔSao2] and the ratio of the change in mouth occlusion pressure over the first 100 ms of inspiration against an occluded airway [ΔP0.1] to Δ Sao2) and hypercapnic responses (Δ V˙e/ΔPco2 ratio andΔP0.1/ΔPco2 ratio) were testedduring wakefulness before treatment in all 10 patients, and before and during treatment (at 2, 4, and 6 weeks) with pressure support in the hypercapnic group. Hypercapnic patients had lower mean (± SD)Δ V˙e/Δ Sao2 ratio than eucapnic patients (−0.17 ± 0.04 vs −0.34 ± 0.04 L /min/% Sao2, respectively), lower meanΔP0.1/Δ Sao2 ratio(−0.04 ± 0.02 vs −0.14 ± 0.03 cm H2O/% Sao2, respectively), and lower ΔP0.1/ΔPco2 ratio(0.23 ± 0.1 vs 0.49 ± 0.1 cm H2O/mm Hg, respectively)[p < 0.05]. After receiving noninvasive ventilation treatment, the hypercapnic and hypoxic responses of the hypercapnic patients increased. At 4 to 6 weeks, values for both responses had increased to within the normal range and Paco2 had fallen to< 45 mm Hg, while weight was unchanged. Depressed chemoresponsiveness plays a role that is independent of obesity in the development of CO2 retention in some OSAHS patients, and it may be a response to sleep-disordered breathing.

Magnesium and its alloys are promising biomaterials due to their biocompatibility and osteoinduction. The plasticity and corrosion resistance of commercial magnesium alloys cannot meet the requirements for degradable biomaterials completely at present. Particularly, the alkalinity in the microenvironment surrounding the implants, resulting from the degradation, arouses a major concern. Micro-arc oxidation (MAO) and poly(lactic acid) (PLA) composite (MAO/PLA) coating on biomedical Mg-1.21Li-1.12Ca-1.0Y alloy was prepared to manipulate the pH variation in an appropriate range. Surface morphologies were discerned using SEM and EMPA. And corrosion resistance was evaluated via electrochemical polarization and impedance and hydrogen volumetric method. The results demonstrated that the MAO coating predominantly consisted of MgO, Mg2SiO4 and Y2O3. The composite coating markedly improved the corrosion resistance of the alloy. The rise in solution pH for the MAO/PLA coating was tailored to a favorable range of 7.5–7.8. The neutralization caused by the alkalinity of MAO and Mg substrate and acidification of PLA was probed. The result designates that MAO/PLA composite coating on Mg-1.21Li-1.12Ca-1.0Y alloys may be a promising biomedical coating.

ABSTRACTStainless steel (SS) has a high corrosion resistance in acetic acid (CH3COOH; HAc) solution and is widely used as a common structural material in the chemical industry. In the production of HAc is used as a solvent and tetrabromoethane (CHBr2CHBr2) as an assistant catalyst. This solution makes reaction containers suffer serious corrosion, including general corrosion and pitting. Although research in this field has not been done, some related research has been performed. The corrosion behavior of AISI 430 SS (UNS S08904)(1) in HAc has been studied.1 It was found that the corrosion rate of SS in the aqueous HAc system was controlled by solution conductivity and the structure of the passive film formed on the material surface. The pitting behavior of SS has been studied extensively in solutions containing chloride as the aggressive ion.2 It was found that, for a given chromium content in a SS, the addition of molybdenum had a strong beneficial influence on passivation.3 There are only a few reports on the pitting behavior of SS in bromide solutions, and the results concerning the effect of molybdenum were inconsistent. A beneficial effect of molybdenum on the pitting resistance of ferritic SS in sodium bromide (NaBr) solution was reported by Bond.4 Guo and Ives found that molybdenum had a less beneficial effect in solutions containing bromide ions than in those containing chloride.5 Another researcher demonstrated that high-molybdenum SS was still susceptible to pitting in bromide solution.6 Recently, Meguid studied the