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• GNS layer induced by SMRT enhanced the strength-ductility synergy of 316L steel. • Gradient microstructure effectively inhibits strain localization during deformation. • SMRT 316L displays phase transformation and cyclic softening under fatigue at 650 ℃. • Fatigue life is well predicted by CPFE model with plastic-slip-based indicator. • Multi-scale failure mechanism is studied for GNS 316L under strain fatigue at 650 ℃. Gradient nanostructured materials have excellent fatigue resistance. At present, there are few research on the fatigue properties of gradient nanostructured (GNS) materials at high temperature. Herein, the multi-scale failure mechanism of GNS 316L steel at 650 °C is studied, and the high temperature fatigue tests under different strain amplitudes are conducted. Then, post-test microstructure observations were carried out to reveal the damage mechanisms, and the fatigue behavior was numerically simulated by crystal plasticity model. The experimental results show that the strength of the GNS 316L steel is still higher than that of the coarse-grained (CG) 316L steel at 650 °C, and the fatigue life of the GNS 316L steel is also higher than that of the CG one under strain fatigue loadings. The fatigue fracture results show that the fatigue crack presents a mixed propagation mode, and the crack source of GNS 316L transfers from surface to subsurface under low strain amplitude. The numerical results directly reflect the influence of the GNS surface layer on the plastic slip behavior. The fatigue failure mechanism of GNS 316L steel under strain-controlled cyclic loading at 650 °C was explained from a multi-scale perspective. This study provides data and method support for the application of GNS 316L steel at high temperature. [ABSTRACT FROM AUTHOR]

• Fatigue failure mechanism was elucidated for multi-stage centrifugal pump shaft. • Specific technical measures to prevent pump shaft failure were proposed. • Fatigue resistance design is performed for pump shaft structure and coupling. • Feasibility of the new pump shaft system has been verified by experiment. In the operation of multistage centrifugal pump, the pump shaft of 304 stainless steel is subjected to a variety of alternating loads. It is one of the parts prone to failure. The fracture microscopic observation, chemical composition analysis and mechanical property measurement of the fractured pump shaft are carried out. Through the fracture analysis, it is found that the pump shaft failure is caused by fatigue mechanism with characteristic of multi-source crack initiation, and there are many cavities and inclusions at the fracture. From the numerical analysis, it is found that there is significant stress concentration at the fracture, which exceeds the fatigue limit of the material and eventually leads to the fatigue fracture. Besides, the appropriate fillet radius and elastic coupling are designed for the pump shaft, which can effectively reduce the stress concentration and improve the service life of the pump shaft. Finally, the fatigue life of the improved pump shaft was experimentally verified. [ABSTRACT FROM AUTHOR]

Given the evident spatial disparity in China's energy consumption and economic development, achieving Pareto optimization of regional energy allocation efficiency proves to be a formidable challenge. Based on this, this paper ingeniously proposed an extended "labor-capital-energy-environment" resource mismatch mode, using 2004–2018 provincial panel data to measure and analyze the spatiotemporal pattern of China's energy mismatch and efficiency loss, while further investigating influencing factor. The results show that: (1) Although the degree of resource misallocation has decreased, the reduction of the number of provinces with excessive energy allocation and the serious shortage of energy allocation are the only effects of the optimization of energy resource misallocation, which has not significantly improved the situation overall. (2) Energy resource misallocation has grown to be a significant factor in China's losses in green total factor productivity (GTFP) brought on by resource misallocation. In addition, the extent of energy mismatch's loss in GTFP demonstrates the spatial heterogeneity of the "eastern > central > northeast > west" region. (3) Environmental regulation can significantly reduce energy mismatch and it is more successful at addressing the issue of excess energy than inadequate energy allocation. Also, the "rebound effect" of technological progress is the main factor aggravating the shortage of energy allocation. • We innovatively proposed an expanded "labor-capital-energy-environment" HK model to construct a theoretical framework for the impact of factor price distortions on GTFP. • The optimization of energy resource misallocation is only reflected in the serious shortage of energy allocation and the reduction of the number of provinces with excessive energy allocation. • The degree of GTFP loss of energy mismatch shows the regional heterogeneity of "eastern > central > northeast > west" spatially. • Environmental regulation can significantly improve the problems of energy mismatch and surplus. [ABSTRACT FROM AUTHOR]

• The radiation induced static mode degradation (SMD) was discovered and studied. • The threshold of SMD could be related with the composition of active fiber and increases with the increase of Ce. • When the Ce concentration increased by 35.5%, SMD threshold rose by 16% at most. We report on an experimental investigation of radiation induced static mode degradation in Yb-Ce co-doped pulsed fiber amplifiers. For investigating the impact of irradiation on beam quality, radiation-darkened fibers were irradiated by gamma rays. The laser properties of three types of fibers were investigated. With the pump power increased, static mode degradation appeared: M2 factor raised significantly and the output beam profile transformed from LP 01 into LP 11 shape without high-frequency component. The threshold of static mode degradation decreased with irradiation dose, and related to Yb-Ce co-doped fiber compositions. The doping of Ce benefits to the improvement of the static mode degradation threshold: in the case of the Ce concentration increasing by 35.5%, SMD threshold rose by 16% at most. [ABSTRACT FROM AUTHOR]

Abstract: Renewable energy generation is considered as an important approach to solve energy and environment problems in the future. Distributed generation technique is a primary way to utilize renewable energy. Microgrid integrated with different kinds of distributed resources can improve energy efficiency and reduce the negative impact on power grid. Microgrid may operate in grid-connected or islanding mode, running on quite different strategies. Effective islanding detection methods are indispensable to realize optimal operation of microgrid. In this paper, performance indices and critical technique problems are discussed. Islanding detection methods are also classified. The paper aims to discuss the improvement of several performance indices, including non-detection zone (NDZ), detection time, error detection ratio and power quality, to evaluate different detection methods. Effectiveness in multiple-inverter cases is also analyzed. According to the comparison upon the advantages and disadvantages of each method, the applicability is discussed, which may provide a reference for researchers to select islanding detection methods. [Copyright &y& Elsevier]

• Three fungus-infecting endornaviruses were evenly distributed within a Ceratobasidium colony growing in vitro. • Endornaviruses co-infecting an isolate of Ceratobasidium were differentially eliminated with antibiotics and hyphal tipping. • Sometimes, endornaviruses that were undetected following antibiotic treatment were detected after incubation on non-selective medium. • Infection with three endornaviruses suppressed fungal growth on glucose minimal agar and soil extraction Agar. • Infection with one or two viruses induced fungal growth on soil extraction agar but suppressed it on glucose minimal agar. Determining roles of mycoviruses in fungal biology is complicated, especially when fungi are co-infected with multiple viruses. Genetically identical (isogenic) fungal lines that are infected by and not infected by viruses must be created and compared. Here, we study an isolate of Ceratobasidium sp., a fungus isolated from pelotons in roots of a wild terrestrial orchid. The fungal isolate was co-infected with three distinct endornaviruses, isolates of Ceratobasidium endonarvirus B (CbEVB), Ceratobasidium endonarvirus C (CbEVC) and Ceratobasidium endonarvirus D (CbEVD). An experiment to reveal natural distribution of the three mycoviruses within a fungal colony revealed no sectoring; they were all evenly distributed throughout the colony. Hyphal tipping and treatments with one of five antibiotics (kanamycin, streptomycin, cycloheximide, rifampicin and ampicillin) were applied in attempts to 'cure' fungal lines of one, two or three of the viruses present. Surprisingly, the three mycoviruses responded differentially to each curing approach. The isolate of CbEVC was eliminated upon treatment with cycloheximide, but not with kanamycin or streptomycin, whereas the isolate of CbEVD did not respond to cycloheximide. The isolate of CbEVB was eliminated upon all treatments. In some cases, a virus was undetectable by species-specific RT-PCR assay after treatment, but when the fungus was cultured for a period on non-selective medium, the virus was detected again. Effects of mycoviruses on growth characteristics of isogenic fungal lines on two nutrient media were studied. Co-infection by the three viruses reduced mycelial growth rate on both media. In contrast, some fungal lines infected with one or two mycoviruses grew more rapidly than virus-free lines. [ABSTRACT FROM AUTHOR]

Scintillators, an important component of optoelectronic materials, have been used extensively for medical imaging and security detection. Currently, most X-ray imaging scintillators rely on inorganic scintillators that use rare earths. Scintillator materials with mild growth conditions, high light yield, environmental friendliness, and low cost are still worth exploring. Here, we prepared novel zero-dimensional (0D) organic-inorganic hybrid zinc halides [C 9 H 14 N] 2 ZnBr 4 (C 9 H 14 N+ = N-butylpyridinium bromide cation) based on pyridine quaternary ammonium salt C 9 H 14 NBr and ZnBr 2. Under UV excitation, the [C 9 H 14 N] 2 ZnBr 4 single crystal shows efficient blue light emission with the center at 426 nm, a large Stokes shift of 129 nm, and a high quantum yield of 49.95 %. In addition, the highly efficient blue emission of [C 9 H 14 N] 2 ZnBr 4 crystals was also able to be excited by X-rays. The [C 9 H 14 N] 2 ZnBr 4 crystal exhibited a relatively low detection limit of 4.995 μGy air s-1. X-ray imaging results based on [C 9 H 14 N] 2 ZnBr 4 scintillation screens demonstrate high-performance X-ray imaging capabilities. According to these results, [C 9 H 14 N] 2 ZnBr 4 crystals are promising X-ray scintillators due to their non-toxicity, excellent luminescence, and good detection performance. [Display omitted] • Novel zero-dimensional organic-inorganic hybrid zinc halide [C 9 H 14 N] 2 ZnBr 4 crystals were synthesized. • Under UV excitation, the [C 9 H 14 N] 2 ZnBr 4 crystals exhibit bright blue light emission. • The electronic properties including energy band structure and density of states were systematically investigated. • Flexible [C 9 H 14 N] 2 ZnBr 4 films prepared as X-ray imaging scintillators exhibit a low detection limit. [ABSTRACT FROM AUTHOR]

Reactor pressure vessel (RPV) is one of the key equipment for nuclear power plant, and long-term exposure to high temperature is an important factor causing its performance deterioration. Under core meltdown conditions, RPV steel experiences high temperature creep due to the In-Vessel Retention (IVR) mitigation measures. This paper aims to investigate high-temperature mechanical properties, especially for the creep behaviors of 16MND5 steel after thermal aging at 650 °C for 2000 h. The results showed that the yield stress and ultimate tensile strength of the 16MND5 steel are decreased, and the creep rupture time is rapidly shortened after thermal aging. The microstructure was analyzed by scanning and transmission electron microscopy (SEM, TEM). 16MND5 steel showed a typical bainitic phase before thermal aging. After 2000 h of thermal aging, the micro-grains were coarsened, and finally changed into a ferritic microstructure. Based on Larson-Miller (LM), Orr-Sherby-Dorn (OSD) parameters methods and Kachanov-Rabotnov (K–R) model to predict uniaxial creep life after thermal aging, the prediction results are satisfactory, and all within the double tolerance band. This work reveals the creep damage mechanism of 16MND5 steel after thermal aging, and provides basic data for the implementation of IVR strategy in nuclear power plants after long-term service. • Characterization of creep behaviors are achieved for 16MND5 steel before and after thermal aging. • Creep failure mechanism of thermal aged 16MND5 steel is explained by microscopic observation. • Influence of thermal aging on macro- and micro-creep failure of 16MND5 steel is understood in depth. • Creep life is well predicted by Larson-Miller and Orr-Sherby-Dorn parameters methods, and validated by experiment. • The K–R model accurately characterizes the three creep stages of thermal aged 16MND5 steel. [ABSTRACT FROM AUTHOR]

A series of B doped TiO 2 samples were synthesized by a simple sol–gel method. The existing states, doping behavior and the influence on the phase transition for the introduced boron ions are investigated and studied in details. It is noted that the B 3+ ions are mainly incorporated into TiO 2 lattice in interstitial mode. The excessive B 3+ ions form surface B 2 O 3 species on the surface of TiO 2 with the increase amount of boron ions. Furthermore, the introduction of B 3+ ions in interstitial mode inhibits the formation of rutile and delay the phase transition. These results afford better realization about the doping mechanism of B doped TiO 2 . [ABSTRACT FROM AUTHOR]

Microbial Fuel Cell (MFC) can degrade the organic matter (OM) in wastewater at the anode and transfer electrons to the cathode. In this work, the harmful NO X gas was used as electron acceptor in MFC and converted to harmless N 2. The OM in water was indirectly used as a zero-cost reducing agent for NOx removal. More than 80% of NO X was removed continuously by MFC at room temperature. The NO X was directly reduced to N 2 at MFC cathode and the cathode activity played a key role on enhancing the NO X removal. The NO X removal efficiency by the cathode of high potential was 1.37 times that by the cathode of low potential. When O 2 coexisting with NO as the electron acceptor, not only the NO X removal but also the power output of MFC was improved greatly. The presence of NO X did not decrease the power generation of MFC under the same O 2 concentration. The MFCs showed good stability for NO X treatment and power output. Moreover, the possible pathways and advantages of NO X removal by MFC were discussed in detail. These results indicated that the MFC system has the potential to treat wastewater, purify flue gas and recover energy simultaneously. ga1 • MFC can remove NOx by using carbon in water as reducing reagent. • The cathode with high activity greatly enhanced the NO X removal efficiency. • The coexistence of O 2 with NO increased both the NOx removal and power output. • MFC maintained good stability for NO X removal. [ABSTRACT FROM AUTHOR]

Aging is an important risk factor for neurodegenerative diseases. The activation of α7 nicotinic acetylcholine receptor (α7nAChR) is involved in inflammation and cognition, but the specific role it plays in aging remains unknown. This study aimed to investigate the anti-aging effect of the activation of α7nAChR on aging rats and BV2 cells induced by D-galactose, as well as its potential mechanism. D-galactose induced an increase in the SA-β-Gal positive cells, expression of p16 and p21 in vivo and in vitro. α7nAChR selective agonist PNU282987 decreased levels of pro-inflammatory factors, MDA, and Aβ, enhanced SOD activity and levels of anti-inflammatory factor (IL10) in vivo. PNU282987 enhanced the expression of Arg1, decreased the expression of iNOS, IL1β and TNFα in vitro. PNU282987 upregulated the levels of α7nAChR, Nrf2 and HO-1 in vivo and in vitro. The results of Morris water maze and novel object recognition tests showed that PNU282987 improved cognitive impairment in aging rats. Furthermore, α7nAChR selective inhibitor methyllycaconitine (MLA) results were opposite with PNU282987. PNU282987 improves cognitive impairment through inhibiting oxidative stress and neuroinflammation in D-galactose induced aging via regulating the α7nAChR/Nrf2/HO-1 signaling pathway. Therefore, targeting the α7nAChR may be a viable therapeutic approach for anti-inflammaging and neurodegenerative diseases. • D-galactose induces microglial senescence and brain aging. • α7nAChR is downregulated in brain aging and senescent BV2 cells. • The activation of α7nAChR by PNU282987 inhibits oxidative stress and neuroinflammation in vivo and in vitro. • PNU282987 inhibits oxidative stress and neuroinflammation by upregulating the α7nAChR /Nrf2/HO-1 signaling pathway, thereby alleviating cognitive impairment caused by aging. [ABSTRACT FROM AUTHOR]

Oxidative stress and neuroinflammation play crucial roles in aging. S-adenosylmethionine (SAM), a popular supplement, is a potential antioxidant and candidate therapy for depression. This study aimed to evaluate the neuroprotective effects of SAM on D -galactose-induced brain aging and explore its underlying mechanisms. Brain aging model was established with D -galactose (180 mg/kg/day) for 8 weeks. During the last 4 weeks, SAM (16 mg/kg) was co-administrated with D -galactose. Behavior tests were used to assess cognitive function and depression-like behaviors of rats. Results showed that cognitive impairment and depression-like behaviors were reversed by SAM. SAM reduced neuronal cell loss, increased brain-derived neurotrophic factor level in the hippocampus, inhibited amyloid-β level and microglia activation, as well as pro-inflammatory factors levels in the hippocampus and serum. Further, SAM enhanced antioxidant capacity and attenuated cholinergic damage by reducing malondialdehyde levels, increasing acetylcholine levels, expression levels of α7 nicotinic acetylcholine receptor (α7nAChR), nuclear factor erythrocyte 2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1) in the hippocampus. Above all, SAM has a potential neuroprotective effect on ameliorating cognitive impairment in brain aging, which is related to inhibition of oxidative stress and neuroinflammation, as well as α7nAChR signals. Data will be made available on request. • Chronic D -galactose exposure leads to cognitive decline and depression-like behavior. • SAM has a neuroprotective effect by inhibiting oxidative stress and neuroinflammation. • SAM improves cognitive impairment by upregulating α7nAChR, Nrf2 and HO-1 protein levels. [ABSTRACT FROM AUTHOR]

[Display omitted] • 0D/2D S-scheme TOCN heterojunction were prepared by phase interfacial reaction. • The heterostructure can effectively separate and transfer photogenerated carriers. • TOCN shows efficient photocatalytic overall water splitting. • The S-scheme can reserve the redox ability of CN and TiO2 nanodots. It is a considerable challenge to design a highly efficient photocatalyst for overall water splitting. Herein, a zero-dimension/two-dimension (0D/2D) TiO 2 nanodots/g-C 3 N 4 step-scheme (S-scheme) photocatalyst (TOCN) for overall water splitting was prepared by a facile phase interfacial reaction. TOCN showed higher photocatalytic water splitting activity under simulated sunlight, which is about 2.2 and 1.7 times higher than TiO 2 nanodots and g-C 3 N 4 , respectively. The enhancement of photocatalytic performance can be mainly attributed to the formation of S-scheme heterojunction, rather than normal type-II heterojunction, which could not only improve charge separation but also remain the redox ability of TiO 2 and g-C 3 N 4. This work presents a simple method to construct an efficient photocatalyst with S-Scheme heterojunction for overall water splitting. [ABSTRACT FROM AUTHOR]