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1.
J Exp Med ; 218(1)2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-32991667

RESUMO

In addition to Foxp3+ CD4+ regulatory T cells (CD4+ T reg cells), Foxp3- CD8+ regulatory T cells (CD8+ T reg cells) are critical to maintain immune tolerance. However, the molecular programs that specifically control CD8+ but not CD4+ T reg cells are largely unknown. Here, we demonstrate that simultaneous disruption of both TGF-ß receptor and transcription factor Eomesodermin (Eomes) in T cells results in lethal autoimmunity due to a specific defect in CD8+ but not CD4+ T reg cells. Further, TGF-ß signal maintains the regulatory identity, while Eomes controls the follicular location of CD8+ T reg cells. Both TGF-ß signal and Eomes coordinate to promote the homeostasis of CD8+ T reg cells. Together, we have identified a unique molecular program designed for CD8+ T reg cells.

2.
J Zhejiang Univ Sci B ; 21(10): 835-840, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33043648

RESUMO

The L(+)-form of tartaric acid (L(+)-TA) exists extensively in nature, and is widely used in the food, chemical, textile, building, and pharmaceutical industries (Su et al., 2001). The main method for L(+)-TA production is microbial transformation by cis-epoxysuccinate hydrolase (CESH), which can catalyze the asymmetric hydrolysis of cis-epoxysuccinic acid or its salts to TA or tartrate (Bao et al., 2019). Seventeen species containing CESH have been isolated so far. However, most species for L(+)-TA production have been reported from bacteria (Xuan and Feng, 2019). The only fungus isolated from soil by our lab recently, that could be used as catalyst for the process under acidic condition, is Aspergillus niger WH-2 (Bao et al., 2020). In order to find strains with new characteristics, this study attempted to isolate a new CESH source from fungi and investigate its application value.

3.
Small ; : e2003361, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33048443

RESUMO

Exploiting spontaneous polarization of ferroelectric materials to achieve high charge separation efficiency is an intriguing but challenging research topic in solar energy conversion. This work shows that loading high work function RuO2 cocatalyst on BiFeO3 (BFO) nanoparticles enhances the intrinsic ferroelectric polarization by efficient screening of charges to RuO2 via RuO2 /BFO heterojunction. This leads to enhancement of the surface photovoltage of RuO2 /BFO single nanoparticles nearly 3 times, the driving force for charge separation and transfer in photocatalytic reactions. Consequently, efficient photocatalytic water oxidation is achieved with quantum efficiency as high as 5.36 % at 560 nm, the highest activity reported so far for ferroelectric materials. This work demonstrates that, unlike low photocurrent density in film-based ferroelectric devices, high photocatalytic activity could be achieved by regulating the ferroelectric spontaneous polarization using appropriate cocatalyst to enhance driving force for efficient separation and transfer of photogenerated charges in particulate ferroelectric semiconductor materials.

4.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(5): 1679-1682, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33067973

RESUMO

OBJECTIVE: To investigate the values of mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), red cell osmotic fragility test(ROFT) and hemoglobin A2(HbA2) in screening of α-thalassemia in Guangdong area. METHODS: A total of 285 peripheral blood samples in patients treated in our hospital from January 2017 to December 2017 were collected. The detection of thalassemia gene was used as the gold standard, while blood routine examination, hemoglobin electrophoresis, and red cell osmotic fragility test were simultaneously performed. The optimal cut-off values in MCV, MCH, ROFT and HbA2 in α-thalassemia were determined by receiver operator characteristic curve (ROC curve). RESULTS: The most common types of α-thalassemia gene was --SEA/αα (54.59%). Compared with the control group, the differences in MCV, MCH, ROFT and HbA2 showed statistically significantce between different types of α-thalassemia (P<0.05). The best cut-off values of MCV, MCH, ROFT, and HbA2 in the diagnosis of α-thalassemia were 81.45 fl, 27.35 pg, 79.95%, and 2.55% respectively. CONCLUSION: For different laboratories, the cut-off values need to be established for screening α-thalassemia suitable in their own local region.The values of MCV, MCH, ROFT and HbA2 shows higher accuracy and sensitivity in the diagnosis of α-thalassemia. It is recommended to use MCV<81.45fl, MCH<27.35 pg, ROFT<79.95% and HbA2<2.55% as the standards for screening α-thalassemia in Guangdong area.


Assuntos
Índices de Eritrócitos , Talassemia alfa , Hemoglobina A2/análise , Humanos , Programas de Rastreamento , Sensibilidade e Especificidade , Talassemia alfa/diagnóstico , Talassemia alfa/genética
5.
J Hazard Mater ; 404(Pt B): 124191, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33069993

RESUMO

Fenton processes based on the reaction between Fe2+ and H2O2 to produce hydroxyl radicals, have been widely studied and applied for the degradation of toxic organic contaminants in wastewater due to its high efficiency, mild condition and simple operation. However, H2O2 is usually added by bulk feeding, which suffers from the potential risks during the storage and transportation of H2O2 as well as its low utilization efficiency. Therefore, Fenton/Fenton-like processes with in-situ production of H2O2 have received increasing attention, in which H2O2 was in-situ produced through O2 activation, then decomposed into hydroxyl radicals by Fenton catalysts. In this review, the in situ production of H2O2 for Fenton oxidation was introduced, the strategies for activation of O2 to generate H2O2 were summarized, including chemical reduction, electro-catalysis and photo-catalysis, the influencing factors and the mechanisms of the in situ production and utilization of H2O2 in various Fenton/Fenton-like processes were analyzed and discussed, and the applications of these processes for the degradation of toxic organic contaminants were summarized. This review will deepen the understanding of the tacit cooperation between the in situ production and utilization of H2O2 in Fenton process, and provide the further insight into this promising process for degradation of emerging contaminants in industrial wastewater.

6.
Ann Palliat Med ; 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33081481

RESUMO

BACKGROUND: To improve the understanding of the characteristics of rare pancreatic cancer spinal metastatic disease and share our experience in coping with this disease. Although spinal metastasis of pancreatic cancer is extremely rare clinically, and the prognosis of the primary tumor is very poor, pancreatic cancer spinal metastasis has received insufficient attention in clinical practice and is only described in a limited number of case reports or series. The purpose of the present study is to discuss the clinical features, prognostic characteristics, and treatment of individuals with pancreatic cancer spinal metastases. METHODS: Four patients with clinical symptoms caused by metastatic spinal pancreatic cancer (MSPC) were selected from patients treated in our department between January 2010 and January 2020. Patients' clinical and surgical records, imaging data, and pathology reports were reviewed by our team. A retrospective analysis of patient clinical data was conducted. RESULTS: Of the four patients, one was male and three were female. The average age was 68.0 (range: 61-79) years old. The average time between the pancreatic cancer diagnosis and the diagnosis of spinal metastases was 10.5 (range: 0-24) months. Spinal metastatic disease was primarily found in the thoracic spine (n=3; 75.0%), and the lumbar spine (n=2; 50.0%). During follow-up, local tumor progression was found in all four patients (100%), all of whom died of pancreatic cancer during follow-up visits. The median time between spinal surgery and death was 16.3 (range: 12-19) months. CONCLUSIONS: Taken together, pancreatic cancer patient that have spinal metastases exhibit a poor prognosis, with a survival time shorter than for any other malignant tumor. Percutaneous vertebroplasty may become an effective treatment option for pancreatic cancer spinal metastasis, which can significantly improve the patient's symptoms.

7.
Biomed Res Int ; 2020: 5262351, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33083469

RESUMO

Background: Several studies have reported conflicting findings regarding the association between tumor necrosis factor-alpha (TNF-α) genetic polymorphisms and acute kidney injury (AKI). Therefore, we performed this meta-analysis to further investigate whether TNF-α variants are related to AKI susceptibility. Methods: A comprehensive search of observational studies on the association of TNF-α polymorphism with AKI susceptibility was conducted in the PubMed, Cochrane, and Embase databases through February 10, 2020. Pooled odds ratios (ORs) and 95% corresponding confidence intervals (95% CIs) were analyzed to evaluate the strength of the relationship. Results: A total of 8 studies involving 6694 patients (2559 cases and 4135 controls) were included. Pooled analysis showed a trend of increased risk between the TNF-α rs1800629 variant and AKI (A vs. G: OR [95%CI] = 1.33 [0.98-1.81]) among the overall population. Ethnicity-stratified analysis indicated that the TNF-α rs1800629 variant was a risk factor for Asians (OR [95%CI] = 1.93 [1.59-2.35]) while it is not for Caucasians (OR [95%CI] = 1.04 [0.91-1.20]). Additionally, we also found that TNF-α rs1799964 polymorphism was observed to have a significant relationship with AKI risk in Asian patients (C vs. T, OR [95%CI] = 1.26 [1.11-1.43]). Conclusions: The TNF rs1800629 polymorphism exhibited a trend toward AKI susceptibility with ethnic differences. The relationship was found to be significant among the Asian population, but not among those of Caucasian origin. Additionally, the TNF-α rs1799964 polymorphism was also related to a significantly increased risk of AKI in Asians.

8.
J Agric Food Chem ; 68(42): 11863-11874, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33030895

RESUMO

Fruit and leaf possess distinctly different metabolites. Here, metabolites and transcriptome were compared between mature leaves (ML) and juice sacs (JS) of Citrus grandis "Hirado Buntan" to investigate the possible reasons. Results indicated that the remarkable difference in starch, total flavonoids and carotenoids, l-ascorbate, and jasmonic acid between ML and JS was tightly related to the expression levels of their biosynthesis-related genes, while the significant difference in abscisic acid and citrate was mainly related to the gene expression level(s) of 9-cis-epoxycarotenoid dioxygenase and proton pump genes, respectively. In addition, ATP citrate lyase probably plays a key role in the levels of flavonoids between ML and JS via providing different levels of acetyl-CoA. Taken together, these results identified some key candidate genes responsible for the content of a given metabolite and will contribute to research in regulating such metabolite content in citrus fruits.

9.
Appl Radiat Isot ; 167: 109436, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-33039757

RESUMO

In this paper, a rapid, simple and reliable quantitative analysis method for Phosphorus and Sulfur in milligram quantities of plant samples by EDXRF has been described. The method uses a thin film sample preparation procedure which includes drying, suspension samples, filtration and pressing of the thin film samples. By measuring four random points of the same thin film sample, the homogenization of thin layer samples was evaluated to ensure the stability of the quantitative analysis results. The calibration curves of P, S, Ca and Fe was established by changing the weight of certified reference materials (CRMs) deposited on the filter. Then, the emission-transmission (E-T) method was used for correcting the matrix absorption effects of phosphorus and sulfur in the thin layer samples. After the correction, the correlation coefficients (R2) of the calibration curves of P and S were higher than 0.99. To evaluate the accuracy of quantitative analysis method, three vegetation verification samples were synthesized by adding the analytical pure powder to CRMs. The quantitative analytical results of EDXRF and ICP-OES were compared to the synthesized value. For P and S elements, the relative error of EDXRF and ICP-OES were 1.2%-6.4% and 4.2 %to 11.4%, respectively.

10.
Phys Rev Lett ; 125(14): 143601, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33064522

RESUMO

We show that a single photon propagating through a Rydberg-dressed atomic ensemble can exchange its spin state with a single atom. Such a spin-exchange collision exhibits both dissipative and coherent features, depending on the interaction strength. For strong interaction, the collision dissipatively drives the system into an entangled dark state of the photon with an atom. In the weak interaction regime, the scattering coherently flips the spin of a single photon in the multiphoton input pulse, demonstrating a generic single-photon subtracting process. An analytical treatment of this process reveals a universal trade-off between efficiency and purity of the extracted photon, which applies to a wide class of single-photon subtractors. We show that such a trade-off can be optimized by adjusting the scattering rate under a novel phase-matching condition.

11.
MMWR Morb Mortal Wkly Rep ; 69(39): 1428-1433, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33001874

RESUMO

Excessive alcohol use is a leading cause of preventable death in the United States (1) and costs associated with it, such as those from losses in workplace productivity, health care expenditures, and criminal justice, were $249 billion in 2010 (2). CDC used the Alcohol-Related Disease Impact (ARDI) application* to estimate national and state average annual alcohol-attributable deaths and years of potential life lost (YPLL) during 2011-2015, including deaths from one's own excessive drinking (e.g., liver disease) and from others' drinking (e.g., passengers killed in alcohol-related motor vehicle crashes). This study found an average of 95,158 alcohol-attributable deaths (261 deaths per day) and 2.8 million YPLL (29 years of life lost per death, on average) in the United States each year. Of all alcohol-attributable deaths, 51,078 (53.7%) were caused by chronic conditions, and 52,921 (55.6%) involved adults aged 35-64 years. Age-adjusted alcohol-attributable deaths per 100,000 population ranged from 20.8 in New York to 53.1 in New Mexico. YPLL per 100,000 population ranged from 631.9 in New York to 1,683.5 in New Mexico. Implementation of effective strategies for preventing excessive drinking, including those recommended by the Community Preventive Services Task Force (e.g., increasing alcohol taxes and regulating the number and concentration of alcohol outlets), could reduce alcohol-attributable deaths and YPLL.†.


Assuntos
Alcoolismo/mortalidade , Expectativa de Vida/tendências , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Adulto Jovem
12.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 5563-5566, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33019238

RESUMO

Wandering pattern classification is important for early recognition of cognitive deterioration and other health conditions in people with dementia (PWD). In this paper, we leverage the orientation data available on mobile devices to recognize dementia-related wandering patterns. In particular, we propose to use deep learning (DL) with long short-term memory networks (LSTM) as classifiers for detecting travel patterns including direct, pacing, lapping and random. Experimental results on a real dataset collected from 14 subjects show that deep LSTM classifiers perform better than traditional machine learning (ML) classifiers. Our proposed method can thus be potentially used in healthcare applications for dementia related wandering monitoring and management.Clinical Relevance- This demonstrates the potential of using readily available yet non-privacy information to detect dementia-related wandering patterns with high accuracy.

13.
Small ; : e2004161, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33000898

RESUMO

This article reports the fabrication of a smart biomimetic enzyme system, which incorporates a pH-responsive chemodynamic therapy (CDT) combined with a photothermal (PTT) therapy approach in resolving the high recurrence rate of deadly cancers. The resulting enzyme system comprises copper sulfide (CuS) nanoparticle (NP) cores as Fenton-like catalysts, and a photothermal-active generation 5 poly(amidoamine) (G5) dendrimer as a template for the entrapment of Cu NPs and the compression of glucose oxidase (GOD). GOD is introduced to produce H2 O2 necessary in the sequential Fenton-like reaction, and this generates hydroxyl radicals that kill the cancerous cells. Polyethylene glycol is added to the system to improve biocompatibility. Mechanism study suggests that the constructed CuS/G5-GOD-based system has a better Fenton-like catalytic activity than a Fe3 O4 -GOD-based system. This allows the further inhibition on the residual tumors from recurrence and metastasis through CDT after being treated by PTT. The developed smart nanoscale biomimetic system shows high efficiency for breast cancer suppression from recurrence and metastasis by combining PTT with a pH-responsive CDT. It has the potential to resolve the essential issue of cancer recurrence after its initial clinic treatment.

14.
Brain Imaging Behav ; 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33033984

RESUMO

Numerous studies have shown that restrained eating is not an effective weight loss strategy. Restrained eaters often suppress their desires and thoughts about tasty food, which makes it more difficult to control themselves in subsequent eating behavior. The ego depletion impairs conflict monitoring abilities. Therefore, this study explored the effects of food thoughts suppression on restrained eaters' conflict monitoring. Therefore, this study used functional magnetic resonance imaging (fMRI) methods to explore changes in the activity of brain regions involved in conflict monitoring when restrained eaters choose between high- and low-calorie foods after either suppressing or not suppressing thoughts about food. The results showed that, compared to the control condition, after suppression of such thoughts, restrained eaters chose more high-calorie foods and displayed decreased activity in the dorsal anterior cingulate cortex-an important region in charge of conflict monitoring. At the same time, the functional coupling of the dorsal anterior cingulate cortex and the precuneus increased. Our findings suggest that restrained eaters' suppression of thoughts about tasty food could lead to a decline in their ability to monitor conflicts between current behaviors and goals, which in turn leads to unhealthy eating behavior.

15.
Phys Rev Lett ; 125(12): 123901, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-33016716

RESUMO

Optical nonreciprocity is an essential property for a wide range of applications, such as building nonreciprocal optical devices that include isolators and circulators. The realization of optical nonreciprocity relies on breaking the symmetry associated with Lorentz reciprocity, which typically requires stringent conditions such as introducing a strong magnetic field or a high-finesse cavity with nonreciprocal coupling geometry. Here we discover that the collision effect of thermal atoms, which is undesirable for most studies, can induce broadband optical nonreciprocity. By exploiting the thermal atomic collision, we experimentally observe magnet-free and cavity-free optical nonreciprocity, which possesses a high isolation ratio, ultrabroad bandwidth, and low insertion loss simultaneously. The maximum isolation ratio is close to 40 dB, while the insertion loss is less than 1 dB. The bandwidth for an isolation ratio exceeding 20 dB is over 1.2 GHz, which is 2 orders of magnitude broader than typical resonance-enhanced optical isolators. Our work paves the way for the realization of high-performance optical nonreciprocal devices and provides opportunities for applications in integrated optics and quantum networks.

16.
BMJ Open ; 10(10): e039009, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33067289

RESUMO

OBJECTIVE: Several studies evaluating the preventive effect of N-acetylcysteine (NAC) on contrast-associated acute kidney injury (CA-AKI) among patients with ST segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI) have suggested inconsistent results and that a systematic review and meta-analysis should be performed. DESIGN: Systematic review and meta-analysis. DATA SOURCES: PubMed, MEDLINE, EMBASE, ClinicalTrials.gov and the Cochrane Central databases were searched from inception to 15 November 2019. ELIGIBILITY CRITERIA: Randomised controlled trials assessing use of NAC compared with non-use of NAC (eg, placebo) in preventing CA-AKI in patients with STEMI following PPCI were included. DATA SYNTHESIS: Relative risks with 95% CIs were pooled using a random-effects model. Evidence level of conclusions was assessed by Cochrane GRADE measure. RESULTS: Seven trials including 1710 patients were identified. Compared with non-use of NAC, use of NAC significantly reduced the incidence of CA-AKI by 49% (risk ratio (RR) 0.51, 95% CI 0.31 to 0.82, p<0.01) and all-cause in-hospital mortality by 63% (RR 0.37, 95% CI 0.17 to 0.79, p=0.01). The estimated effects on the requirement for dialysis (RR 0.61, 95% CI 0.11 to 3.38, p=0.24) were not statistically significant. Trial sequential analysis confirmed the true positive of NAC in reducing risk of CA-AKI. Subgroup analyses suggested that the administration of NAC had greater benefits in patients with renal dysfunction and in those receiving oral administration and higher dosage of NAC. CONCLUSIONS: NAC intake reduces the risk of CA-AKI and all-cause in-hospital mortality in patients with STEMI undergoing PPCI. The estimated potential benefit of NAC in preventing dialysis was ambiguous, and further high-quality studies are needed. PROSPERO REGISTRATION NUMBER: CRD42020155265.

17.
J Clin Neurosci ; 79: 172-177, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33070891

RESUMO

PURPOSE: Fatigue has been recognized as a common non-motor problem in patients with Parkinson's disease (PD). The determination of the clinical correlates of fatigue in PD patients is necessary. The purpose of this study was to explore the risk factors related to the severity of fatigue in PD. PATIENTS AND METHODS: In this study, 141 patients with PD were recruited. All patients were evaluated comprehensively, including motor function, fatigue severity scale (FSS), cognition and psychiatric status. Brain magnetic resonance imaging (MRI) examinations were performed to assess the severity of white matter hyperintensities, and the presence of silent lacunes, medial temporal lobe atrophy (MTLA), and global cortical atrophy (GCA). The crude associations of variables with FSS were examined using Pearson (nor-mally distributed) or Spearman correlation (categorical or non-normal distributed) analyses. Multiple linear regression analysis was performed to find the correlates of fatigue severity in PD patients. RESULTS: In the whole sample, with FSS as the dependent variable in a linear regression model, Hamilton Depression Rating Scale (HAM-D), GCA, female sex were significant correlates of FSS, accounting for 24% of the variance of it. When subjects with depression (HAM-D ≥ 35) were excluded, HAM-D, GCA, female sex remained significant correlates of FSS, accounting for 22% of the variance of FSS. There is no correlation between white matter hyperintensities and FSS. CONCLUSION: GCA may be an important correlate of the fatigue severity commonly observed in PD patients.

18.
Exp Physiol ; 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33026112

RESUMO

NEW FINDINGS: What is the central question of this study? The relevance of miR-22 has been indicated in coronary heart disease (CHD), while how its protective role exerted in CHD has not been previously reported. What is the main finding and its importance? EZH2 inhibited miR-22 promoter transcription, thus modulating cell proliferation in human umbilical vein endothelial cells and vascular smooth muscle cells to induce CHD. ABSTRACT: microRNA-22 (miR-22) was indicated to modulate cell proliferation in human umbilical vein endothelial cells (HUVECs) under exposure to environmental toxicants. In the current study, we excavated the involvement of miR-22 in the mediation of HUVECs and vascular smooth muscle cells (VSMCs) function, thereby in the development of coronary heart disease (CHD). miR-22 expression was reduced in serum of CHD patients. Restoration of miR-22 decreased the proliferation, migration and invasion of VSMCs and increased apoptotic cells and inflammatory factors. By contrast, miR-22 upregulation led to opposite trends in HUVECs. ChIP and dual-luciferase assays validated that enhancer of zeste homolog 2 (EZH2) inhibited miR-22 promoter transcription. EZH2, overexpressed in CHD patient serum, diminished VSMC apoptosis, yet facilitated HUVEC apoptosis. Luciferase reporter assays confirmed that thioredoxin-interacting protein (TXNIP) was a novel direct target of miR-22. Overexpression of TXNIP blocked the role of miR-22 in HUVECs and VSMCs. Taken together, these findings will shed lights on the role and mechanism of EZH2 in viability, migration, invasion and apoptosis via miR-22/TXNIP axis in VSMCs and HUVECs, which may provide novel insights into the treatment of CHD. This article is protected by copyright. All rights reserved.

20.
Materials (Basel) ; 13(19)2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33007907

RESUMO

The fundamental challenge for creating the crystal structure model used in a multi-principle element design is the ideal combination of atom components, structural stability, and deformation behavior. However, most of the multi-principle element alloys contain expensive metallic and rare earth elements, which could limit their applicability. Here, a novel design of low-cost AlCrTiFeNi multi-principle element alloy is presented to study the relationship of structure, deformation behavior, and micro-mechanism. This structured prediction of single-phase AlCrTiFeNi by the atomic-size difference, mixing enthalpy ΔHmix and valence electron concentration (VEC), indicate that we can choose the bcc-structured solid solution to design the AlCrTiFeNi multi-principle element alloy. Structural stability prediction by density functional theory calculations (DFT) of single phases has verified that the most advantageous atom occupancy position is (FeCrNi)(AlFeTi). The experimental results showed that the structure of AlCrTiFeNi multi-principle element alloy is bcc1 + bcc2 + L12 phases, which we propose as the fundamental reason for the high strength. Our findings provide a new route by which to design and obtain multi-principle element alloys with targeted properties based on the theoretical predictions, first-principles calculations, and experimental verification.

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