•The temperature and strain rate dependence of deformation behaviors of superalloy GH3536 were investigated.•The effects of stress triaxiality, temperature, and strain rate on the fracture behavior ...of superalloy GH3536 were studied.•Modified J–C constitutive model was developed to accurately describe the deformation behaviors.•Modified J–C fracture criterion was developed to characterize the fracture behaviors.•Impact resistance of honeycomb structure made from the superalloy were tested at different temperatures, impact velocities and impact angles.
In this study, to further understand the containment properties of a containment ring, the deformation behavior of GH3536 superalloy used as the material of the containment ring were investigated over a wide range of temperatures and strain rates. The effects of stress triaxiality, temperature, and strain rate on the fracture behavior of the superalloy were analyzed. According to the temperature and strain rate dependences of the deformation behavior, the original Johnson-Cook constitutive model (J––C model) was unable to describe such behavior, and a modified J–C model was developed. In view of the stress triaxiality, temperature and strain rate dependences of the fracture behavior, the original Johnson–Cook fracture criterion (J–C criterion) was inapplicable to describe such fracture behavior, and a modified J–C criterion was proposed. Finally, the impact resistance of honeycomb structure made from the superalloy and applied on the containment ring were tested at different temperatures, impact velocities and impact angles. Using the modified J–C model and J–C criterion, the resistance property of the honeycomb structure could be accurately predicted.
Phytic acid (PA)-modified MXene (P-MXene) was prepared combination selective etching with assemble method, and was mixed with epoxy resin (EP) to investigated its flame retardancy, thermal ...conductivity, conductivity and mechanical properties. P-MXene exhibited two-dimensional single layer structure and had good char-forming property with 86.7% char residue at 800 °C. The cone calorimetry test results showed that P-MXene endowed EP with excellent flame retardancy. Compared with pure EP, the peak heat release rate, peak smoke release rate, peak CO generation rate, and peak CO2 generation rate of EP composites with 2 phr P-MXene decreased by 38.6%, 31.6%, 38.7% and 40.6%, respectively. The flame retardant mechanism was attributed to physical barrier, catalyzing carbonization effect, oxidative thermal degradation and physical barrier effect. Additionally, the conductivity and mechanical properties of EP composites were slightly reduced. This work provides a promising method to design multifunctional polymers.
•P-MXene was synthesized by liquid etching and in situ assemble to improve the flame retardancy of EP.•P-MXene endowed EP with excellent flame retardancy with decreased PHRR, PSPR, PCOP and PCO2P value.•The flame-retardant mechanism is the combination of gas phase and condensed phase.•EP/P-MXene composites had remarkable comprehensive performance, including mechanical property and thermal conductivity.
A series of chitosan-modified inorganic oxyacid salt flame retardants (IOS-CS) were synthesized and used as flame retardants to improve the fire resistance of poly(vinyl chloride) (PVC) composites ...while improving the mechanical properties of the materials. The thermal stability of the material was analyzed by TG test; the flame-retardant and smoke suppression properties were evaluated by limiting oxygen index (LOI) and cone calorimeter test, and the mechanical properties were analyzed by tensile test and impact test. The TG results showed that the addition of flame retardant can promote the early cross-linking decomposition of PVC composites, not only advance the decomposition temperature of the material but also promote the formation of char layer and increase the char residual content. LOI and cone calorimeter test results showed that stannate chitosan (Sn-CS) can improve flame retardant and smoke suppression more effectively than other samples. Compared with pure PVC, the addition of Sn-CS increased its LOI from 26.6 to 30.5% and reduced the total heat release value and total smoke release by 18.23% and 52.55%, respectively. At the same time, the addition of the flame retardants had no large deterioration effect on the mechanical properties of the material. The tensile properties of flame-retardant PVC were slightly reduced compared with pure PVC, and the impact resistance was even improved to some extent.
A novel ionic liquid-modified flake-NiNH4PO4·H2O (IL-ANP) hybrid material was prepared using a mechanochemical method with weak interactions. Characterization methods, including scanning electron ...microscope, Fourier transform infrared, X-ray diffraction and thermogravimetric analysis indicated the successful synthesis of IL-ANP. The prepared IL-ANP was incorporated into epoxy resin (EP) to improve the flame retardancy and mechanical properties. The limiting oxygen index (LOI) and cone calorimeter tests showed that IL-ANP enhanced the flame retardancy of EP composites. The 6 part per hundred resin (phr) IL-ANP/EP achieved excellent flame retardancy with the LOI value of 30.3% (that of pure EP was 24.4) and a significant decrease in the peak heat release rate, total heat release rate and the maximum release rates of CO production. This is attributed to the synergistic effect of the condensed phase and gas phase. During combustion, IL-ANP generated an incombustible gas (ammonia gas), nickel phosphate and nickel phosphide. On one hand, the incombustible gas diluted the concentrations of the combustible gas and oxygen in the gas phase. On the other hand, the phosphorus compounds catalyzed the carbonisation of EP to form a stable char layer and accumulated on the char layer surface as a physical barrier to delay the heat release. Additionally, the IL-ANP/EP composites exhibited excellent tensile strength, elongation at break, and impact strength, owing to their good compatibility and dispersion.
•Novel flake-IL-ANP hybrid material was prepared by mechanochemical method to improve the flame retardancy of epoxy resin.•The LOI and the cone calorimeter test exhibited that IL-ANP enhanced the flame retardancy of EP composites.•The flame-retardant mechanism is the combination with condensed phase and gas phase.•IL-ANP/EP composites had remarkable tensile strength, elongation at break, and impact strength.
Correlations between pain phenotypes and psychiatric traits such as depression and the personality trait of neuroticism are not fully understood. In this study, we estimated the genetic correlations ...of eight pain phenotypes (defined by the UK Biobank, n = 151,922-226,683) with depressive symptoms, major depressive disorders and neuroticism using the the cross-trait linkage disequilibrium score regression (LDSC) method integrated in the LD Hub. We also used the LDSC software to calculate the genetic correlations among pain phenotypes. All pain phenotypes, except hip pain and knee pain, had significant and positive genetic correlations with depressive symptoms, major depressive disorders and neuroticism. All pain phenotypes were heritable, with pain all over the body showing the highest heritability (h
= 0.31, standard error = 0.072). Many pain phenotypes had positive and significant genetic correlations with each other indicating shared genetic mechanisms. Our results suggest that pain, neuroticism and depression share partially overlapping genetic risk factors.
Myopia, or nearsightedness, is a worldwide common type of refractive error. It is a non-life-threatening disorder with huge social and economic consequences due to its increasing prevalence. Axial ...length (AL) is the primary determinant of non-syndromic myopia. It is a parameter representing the combination of anterior chamber depth, lens thickness and vitreous chamber depth of the eye. AL can also be treated as an endophenotype of myopia and may provide extra advantages in the investigation of its genetic basis. The study of AL will not only identify the determinants of eye elongation, but also provide aetiological evidence for myopia. The purpose of this review is to outline the current state of AL research. Epidemiological evidence, genetic determinants, the relationship with other eye components and relative animal models of AL are summarised.
Neuropathic pain (NP) is an increasingly common chronic pain state and a major health burden, affecting approximately 7% to 10% of the general population. Emerging evidence suggests that genetic ...factors could partially explain individual susceptibility to NP and the estimated heritability in twins is 37%. The aim of this study was to systematically review and summarize the studies in humans that have investigated the influence of genetic factors associated with NP. We conducted a comprehensive literature search and performed meta-analyses of all the potential genetic variants associated with NP. We reviewed 29 full-text articles and identified 28 genes that were significantly associated with NP, mainly involved in neurotransmission, immune response, and metabolism. Genetic variants in HLA genes, COMT, OPRM1, TNFA, IL6, and GCH1, were found to have an association with NP in more than one study. In the meta-analysis, polymorphisms in HLA-DRB1*13 (odds ratio OR, 2.96; confidence interval CI, 1.93-4.56), HLA-DRB1*04 (OR, 1.40; CI, 1.02-1.93), HLA-DQB1*03 (OR, 2.86; CI, 1.57-5.21), HLA-A*33 (OR, 2.32; CI, 1.42-3.80), and HLA-B*44 (OR, 3.17; CI, 2.22-4.55) were associated with significantly increased risk of developing NP, whereas HLA-A*02 (OR, 0.64; CI, 0.47-0.87) conferred reduced risk and neither rs1799971 in OPRM1 (OR, 0.55; CI, 0.27-1.11) nor rs4680 in COMT (OR, 0.95; CI, 0.81-1.13) were significantly associated with NP. These findings demonstrate an important and specific contribution of genetic factors to the risk of developing NP. However, large-scale replication studies are required to validate these candidate genes. Our review also highlights the need for genome-wide association studies with consistent case definition to elucidate the genetic architecture underpinning NP.
Novel core-shell graphitic carbon nitride/zinc phytate (g-C
N
/PAZn) flame retardant was simple synthetized using two-dimensional g-C
N
and bio-based PAZn by self-assembly and incorporated into epoxy ...resin (EP) for improving the fire safety. The flame retardance and smoke suppression were investigated by cone calorimetry. The results indicated that g-C
N
/PAZn-EP displayed outstanding flame retardancy and smoke suppression, for example, the peak heat release rate and peak smoke production rate decreased by 71.38% and 25%, respectively. Furthermore, the flame retardancy mechanism was further explored by char residue and thermal stability analysis. It can be predicted that g-C
N
/PAZn will provide valuable reference about bio-based flame retardant.
High-resolution multi-spectral images are desired for applications in remote sensing. However, multi-spectral images can only be provided in low resolutions by optical remote sensing satellites. The ...technique of pan-sharpening wants to generate high-resolution multi-spectral (MS) images based on a panchromatic (PAN) image and the low-resolution counterpart. The conventional deep learning based pan-sharpening methods process the panchromatic and the low-resolution image in a feedforward manner where shallow layers fail to access useful information from deep layers. To make full use of the powerful deep features that have strong representation ability, we propose a two-path network with feedback connections, through which the deep features can be rerouted for refining the shallow features in a feedback manner. Specifically, we leverage the structure of a recurrent neural network to pass the feedback information. Besides, a power feature extraction block with multiple projection pairs is designed to handle the feedback information and to produce power deep features. Extensive experimental results show the effectiveness of our proposed method.
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