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Due to its lightweight, high strength, good machinability, and low cost, aluminum alloy has been widely used in fields such as aerospace, automotive, electronics, and construction. Traditional manufacturing processes for aluminum alloys often suffer from low material utilization, complex procedures, and long manufacturing cycles. Therefore, more and more scholars are turning their attention to the laser powder bed fusion (LPBF) process for aluminum alloys, which has the advantages of high material utilization, good formability for complex structures, and short manufacturing cycles. However, the widespread promotion and application of LPBF aluminum alloys still face challenges. The excellent printable ability, favorable mechanical performance, and low manufacturing cost are the main factors affecting the applicability of the LPBF process for aluminum alloys. This paper reviews the research status of traditional aluminum alloy processing and LPBF aluminum alloy and makes a comparison from various aspects such as microstructures, mechanical properties, application scenarios, and manufacturing costs. At present, the LPBF manufacturing cost for aluminum alloys is 2–120 times higher than that of traditional manufacturing methods, with the discrepancy depending on the complexity of the part. Therefore, it is necessary to promote the further development and application of aluminum alloy 3D printing technology from three aspects: the development of aluminum matrix composite materials reinforced with nanoceramic particles, the development of micro-alloyed aluminum alloy powders specially designed for LPBF, and the development of new technologies and equipment to reduce the manufacturing cost of LPBF aluminum alloy. [ABSTRACT FROM AUTHOR]

Objective Unravel the potential mechanism(s) of the on- and off-target actions of dopamine agonist therapy in both human prolactinoma tumors and neighboring stromal and immune cells. Design and Methods Five surgically resected prolactinomas (PRLomas) from 3 cabergoline (CBG)-treated patients and 2 treatment-naive patients were analyzed by using single-cell RNA sequencing (scRNA-seq) to compare the cellular composition and transcriptional landscape. Results Six major cell populations, namely tumor (88.2%), immune (5.6%), stromal (4.9%), progenitor cells (0.6%), proliferating cells (0.4%), and erythrocytes (0.2%), were observed. Tumor cells from CBG-treated patients expressed lower levels of genes that regulated hormone secretion, such as SCG2, VGF, TIMP1, NNAT, and CALD1, consistent with the inhibitory effects of CBG on hormone processing and secretion. Interestingly, we also observed an increased number of CD8+ T cells in the CBG-treated tissues. These cytotoxic CD8+ T cells expressed killing granule components such as perforin and the granzymes GZMB, GNLY, and KLRD1 as well as the inflammatory cytokine CCL5. Immune cell activation of these CD8+ T cells was further analyzed in a compartment-specific manner, and increased CD25 (IL2R) expression was noted in the CD8+ T cells from the CBG-treated samples. Additionally, and confirming prior reports, we noted a higher stromal cell population in the CBG-treated samples. Conclusions Our scRNA-seq studies revealed key differences in the transcriptomic features of CBG-treated and CBG-untreated PRLomas in both tumor and microenvironment cellular constituents, and for the first time, describe the previously unknown activation of CD8+ T cells following CBG treatment, which may play a role in the tumoricidal actions of CBG. [ABSTRACT FROM AUTHOR]

The building quality of the LPBF (laser powder bed fusion)-fabricated component is critical to determine whether it can be applied in the serving condition. However, it is determined not only by process parameters; the powder property and its affecting factors such as average particle sizes and particle size distribution of powder materials have also significant effect on the building quality. In order to investigate the correlation between the building quality and powder properties, five kinds of powder materials with different average particle sizes and particle size distributions of P μ 20 , σ 10 , P μ 35 , σ 10 , P μ 50 , σ 10 , P μ 35 , σ 5 , and P μ 35 , σ 15 are prepared on the basis of the Horsfield filling method. The powder properties such as flowability and apparent density are tested, the build qualities such as dimensional accuracy and surface roughness are measured, and their correlation is analyzed. The results show that the powder material with a narrower particle size distribution benefits flowability. That with medium particle size distribution and average particle size, such as P μ 35 , σ 10 , possesses the highest apparent density and acceptable flowability, and the components manufactured with such powder material have the best surface roughness and dimensional accuracy. Besides, an amount of fine particles is required to optimize component density. The above systematic experiments exhibit the correlation among the particle size distribution and the average particle size, powder properties, and build quality, which is beneficial to preparing the powder materials, improving the irradiation conditions of the laser beam, controlling the LPBF process, and further the building quality of LPBF-fabricated component. [ABSTRACT FROM AUTHOR]

In order to track the free interface of the melt pool and understand the evolution of the melt pool, the flow of fluid, and the interface behavior of gas and liquid, a physical model is developed by using the VOF method in this paper. Its characteristics are a combined heat source model, including a parabolic rotation and a cylindrical distribution, and a powder bed stochastic distributed model with powder particle size. The unit interface between the metallic and gas phase in the laser–powder interaction zone can only be loaded by the heat source. Only the first and second laser scanning tracks are simulated to reduce the calculation time. The simulation results show that process parameters such as laser power and scanning speed have significant effects on the fluid flow and surface morphology in the melt pool, which are in good agreement with the experimental results. Compared with the first track, the second track has larger melt pool geometry, higher melt temperature, and faster fluid flow. The melt flows intensely at the initial position due to the high flow rate in the limited melt space. Because there is enough space for the metal flow, the second track can obtain smooth surface morphology more easily compared to the first track. The melt pool temperature at the laser beam center fluctuates during the laser scanning process. This depends on the effects of the interaction between heat conduction or heat accumulation or the interaction between heat accumulation and violent fluid flow. The temperature distribution and fluid flow in the melt pool benefit the analysis and understanding of the evolution mechanism of the melt pool geometry and surface topography and further allow regulation of the L-PBF process of Ti6Al4V. [ABSTRACT FROM AUTHOR]

Objectives: Myocardial I/R injury is one of the most serious complications after reperfusion therapy in patients with myocardial infarction. Remifentanil has been found to protect the heart against I/R injury. However, its underlying mechanism remains uncertain in myocardial I/R injury. Methods: The myocardial I/R injury rat model was established by 30 min of ischaemia followed by 24 h of reperfusion. The animal model was evaluated by the levels of TC, ALT and AST and H&E staining. The binding of miR-206-3p and TLR4 was predicted and verified using TargetScan software, luciferase reporter and RNA pull-down assays. The functional role and mechanism of remifentanil were identified by ultrasonic echocardiography, oxidative stress markers, H&E, Masson and TUNEL staining and western blot. Key findings: The rat myocardial I/R injury model displayed a significantly high level of TC, ALT, AST, TLR4, p-IκBα and p-p65 and the presence of disorganized cells and inflammatory cell infiltration. The model also showed increased levels of LVEDD, LVESD, MDA, fibrosis and apoptosis and decreased levels of EF, FS, SOD and GSH, which were reversed with remifentanil treatment. Knockdown of miR-206-3p damaged cardiac function and aggravated oxidative stress. miR-206-3p could directly bind to TLR4. TLR4 overexpression destroyed cardiac function, exacerbated oxidative stress, increased levels of p-IκBα and p-p65 and aggravated pathology manifestation affected by remifentanil. Conclusions: Our results elucidated that remifentanil alleviated myocardial I/R injury by miR-206-3p/TLR4/NF-κB signalling axis. [ABSTRACT FROM AUTHOR]

Lithium-iron phosphate (LiFePO 4) monocrystalline platelets (LFP-P) with ac facet-preferred growing were obtained by a solvothermal method. Based on its anisotropy, a LiFePO 4 cathode (LFP-PM) with the b axis-oriented aligning was prepared by magnetic orientation. The structure, morphology and magnetic performance of the LFP-P were studied by X-ray diffractometry, scanning-electron microscopy, transmission-electron microscopy and superconducting quantum-interference device technologies. The LFP-P exhibited paramagnetic behavior and its b axis had the largest magnetic susceptibility, which made the LFP-P stack parallel to the magnetic field. It resulted in a higher lithium-ion diffusion coefficient of the LFP-PM (1.6855 × 10−11 cm2 s−1) compared with that of the LiFePO 4 cathode (LFP-PU) prepared without magnetic orientation (1.2538 × 10−11 cm2 s−1). The faster lithium-ion diffusion was contributed to a higher reversibility at 0.1 mV s−1 and higher discharge capacities of the LFP-PM at high rates ≥2 C. For the first time, LiFePO 4 monocrystalline platelets were made to align along b axis through magnetic orientation. It was proved to be an effective means of enhancing high rate performance. Unlabelled Image • LiFePO 4 monocrystalline platelets of ac facet preferred (LFP-P) were synthesized. • B axis oriented-aligning of LFP-P was carried out by magnetic orientation. • SQUID results showed that the LFP-PM had the most magnetic susceptibility. • The LFP-PM exhibited a 13.2% greater discharge capacity than LFP-PU at 10 C. • Magnetic orientation gave LFP-PM a higher D Li + (1.6855 × 10−11 cm2 s−1). [ABSTRACT FROM AUTHOR]

Vat photopolymerization 3D printing of Si 3 N 4 ceramics has attracted great attention recently. To overcome the low curing depth limitation caused by α-Si 3 N 4 , β-Si 3 N 4 with low absorbance and large particle size was selected in this paper. After printing, the effects of pressureless sintering temperatures on mechanical and dielectric properties were systematically investigated. At 1800 °C, the real permittivity of Si 3 N 4 ceramics was 7.37, and the maximum bending strength was 367 ± 75 MPa. Considering the application of Si 3 N 4 ceramics in radomes/windows, the dielectric constant of Si 3 N 4 ceramics should be further reduced. Therefore, the octet-truss lattice structure was introduced to optimize the porosity of ceramics. As the porosity increased from 25% to 36%, the real permittivity decreased from 5.56 to 4.42, and the bending strength ranged from 98 ± 7–62 ± 13 MPa. It shows that vat photopolymerization 3D printing can be a promising technology for the fabrication of wave-transparent Si 3 N 4 ceramics. [ABSTRACT FROM AUTHOR]

Abstract In the paper, the effects of porosities and average particle sizes of powder layer on light absorption during SLM process were investigated, in which closed-packing models based on Horsfieled's filling method were established and light absorption was simulated using ray tracing based on laser-material interaction mechanism. Corresponding to closed-packing models, the powder materials were prepared for absorption measurement using integrating sphere. The experimental results of light absorption verify the feasibility of the establishment of closed-packing models, the accuracy in calculation in the light absorption. The results show the absorption of powder layer of Ti6Al4V alloy is higher than 70%. The decrease of porosity of powder layer benefits to improve the absorption, while the absorption tends to decrease if porosity decreases to a certain value due to the reflection. The decrease of average particle size of powder particles benefits also to improve the absorption. If the light irradiates at positions with different particle arrangements, the absorption behavior changes with irradiation condition whether there occurs the multi-reflection. The above research provides theoretical basis for preparation of new powder materials, their parameter developing for SLM technology and even the properties regulation of SLM fabricated component. [ABSTRACT FROM AUTHOR]

The paper comparatively investigates the microstructures and mechanical properties of Inconel 718 superalloy manufactured by selective laser melting (SLM) and casting. The finite element analysis (FEA) method is used to simulate the temperature fields during SLM and casting processes. Driven by ultra-high temperature gradient and ultra-fast cooling rate during SLM process, the fine grains (average grain size of 48 µm) and dispersed fine precipitation in SLM-ed sample even after HSA (homogenization + solution + aging) and HA (homogenization + aging) heat treatment significantly enhance its mechanical properties, which far exceeds that of casting with average grain size of 1300 µm, and is comparable to that of forging. The microstructure of casting with coarse irregular Laves phases, acicular δ precipitates and globular carbides in the interdendritic zones after HSA heat treatment and some defects existed possibly result in premature failure of tensile samples. The microstructure without δ phases but only some globular carbides in the grain boundary of SLM-ed sample after HA heat treatment possesses higher mechanical properties than that after HSA heat treatment, in which there is only some finer needle-like δ phase and few carbides are precipitated in the grain boundaries. The analysis shows the large amounts of δ phase precipitated in the matrix will deteriorate the plasticity of SLM-ed IN718 superalloy, the appropriate reduction of the δ phase will improve the strength and plasticity of material simultaneously. [ABSTRACT FROM AUTHOR]

In this paper, in order to effectively utilize salt lake magnesium resources, we focused on a functional material containing magnesium, i.e. magnesium oxide, MgO, which is a type of antibacterial material. Through a first-principles study from the atomic level, the microstructure of MgO containing doped point defects of different elements was studied. The relationship between the microscopic structure of the material and its special antibacterial function was explored. The results are as following: the interstitial impurities in MgO are more helpful than substituted impurities for the improvement of the electronic structure. The analysis of the influence of different doping elements on the microstructure confirmed theoretically that Ag and Cu have the same highly active antimicrobial properties with the same change of microstructure, thereby confirming the relationship between microstructure and antimicrobial activity. The results of the simulations match the experimental results, thereby theoretically demonstrating the relationship between defects and antibacterial activities and providing further insight into the nature of the antibacterial mechanism. [ABSTRACT FROM AUTHOR]

With the continuous progress of medical technology, intelligent medical diagnosis systems have become an important direction for the development of medical technology. In terms of cerebral vascular examination, magnetic resonance cerebrovascular imaging has become one of the conventional examination methods. It can be used to evaluate cerebrovascular diseases, such as aneurysms, cerebral vascular stenosis, cerebral vascular malformations, etc. The purpose of this article is to study the application value of intelligent medical systems combined with magnetic resonance cerebrovascular imaging technology in the diagnosis of intracranial aneurysms. The researchers selected 50 patients for the experiment. Among them, the experimental group patients used intelligent medical systems for auxiliary diagnosis, while the control group patients used conventional diagnostic methods. By using magnetic resonance cerebrovascular imaging to diagnose patients, researchers compared the diagnostic results of two groups of patients to evaluate the application effect of intelligent medical systems in the diagnosis of intracranial aneurysms. After the experiment, the vascular visualization score of the experimental group was 3.645 ± 0.489, while the score of the control group was 3.598 ± 0.558 (P < 0.05). After the experiment, the saturation artifact score of the experimental group was 3.933 ± 0.249, while the score of the control group was 2.805 ± 0.539 (P < 0.05), indicating that the scanning sequence score of the experimental group was better than that of the control group. The intelligent medical system has optimized the magnetic resonance imaging module to better extract user symptoms and apply it to medical diagnosis. [ABSTRACT FROM AUTHOR]

Pre-menopausal female patients have a prolonged survival than post-menopausal patients, indicating that estrogen and/or estrogen receptor (ER) may have some biological effects on prognosis. ER expression in cancer tissue has been reported to be a significant prognostic marker in multiple human cancers. However, the prognostic value of estrogen and/or ER on female patients with esophageal squamous cell carcinoma (ESCC) is rarely reported. The present study was undertaken to elucidate the associations of serum estradiol level, tissue estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ) expression with clinical response and reproductive factor changes in 387 female ESCC patients. Radioimmunoassay revealed that serum estradiol level was higher in pre-menopausal than those in peri -menopausal and post-menopausal patients. Furthermore, patients with higher serum estradiol level appeared to have a better survival. Immunostaining results suggested that ERα positive (+) expression was mainly located in cytoplasm of tumor cells with a positive rate of 69.9% and ERβ (+) was mainly located in nucleus of tumor cells with a positive rate of 64.9%. We did not find the relations of ER expression with tumor invasion (P > 0.05), lymph node metastasis (P > 0.05), TNM staging (P > 0.05) and treatment method (P > 0.05). Surprisingly, ERα (+) expression was higher in post-menopausal patients than those in pre-menopausal patients (P < 0.05). Patients with number of pregnancy ≥ 4 have a higher ERβ (+) expression than those patients with ≤ 3 (P < 0.05). Univariate and multivariate survival analysis showed that ERβ (+) expression in addition to ERα (−) expression are favorable prognostic markers in female ESCC patients (P < 0.05). Further related study is needed to in-depth explore the potential mechanisms of ERα and ERβ in survival of female patients with ESCC. [ABSTRACT FROM AUTHOR]

It is of great importance to thoroughly explore the evolving temperature fields of direct laser metal deposition (abbreviated as LMD) in vertical thin wall manufacturing. It is helpful to control the temperature gradient, and even to adjust to forming microstructures and accumulation of residual stress. In this paper, a comprehensive three-dimensional transient model is developed for evolving temperature fields. The manufactured material is DS superalloy Rene80. The laser-powder interaction during the powder flowing process is simulated first, and its possible effect on the temperature field of the melting pool is analyzed. Then a 3D numerical simulation for the evolving temperature field is carried out based on considering transport phenomena during LMD such as the change in phase, powder injection and liquid flow. The applied deposition parameters are derived from experimental investigation with optimized vertical wall manufacturing. The simulated results explain why a balance between heat input and dissipation could form inside the vertical thin wall. These reconstruct the instability at an early phase of the building process without any temperature control unit and exhibit the influence of parameters such as laser power, deposition velocity and laser beam deposition pattern. The simulation results of temperature evolution are consistent with experimental investigation. [ABSTRACT FROM AUTHOR]

Orange–yellow emitting long afterglow phosphors Li 2 Ca 0.4 Sr 0.6 SiO 4 :Eu 2+ , and Li 2 Ca 0.4 Sr 0.6 SiO 4 :Eu 2+ ,Dy 3+ were synthesized via a high temperature solid-state reaction in a reducing atmosphere (N 2 :H 2 =95:5). X-ray diffraction (XRD), photoluminescence spectroscope (PLS), long afterglow spectroscope (LAS), thermal luminescence spectroscope (TLS) were performed to characterize the physical properties of the prepared phosphors. Typical 4f 6 5d 1 →4f 7 transitions of Eu 2+ ions were detected by PL spectra, revealing a broad and intensive emission extending from 500 to 700 nm with a peak at about 587 nm, corresponding to CIE chromaticity coordinates of x =0.5368, y =0.4593, in the orange–yellow region. Optimal concentrations of Eu 2+ and Dy 3+ in the substrate were determined as 7 at% and 3 at%, respectively. The prepared phosphors showed a typical afterglow behavior when the UV source was switched off. Typical triple exponential decay behaviors were confirmed after fitting the experimental data for both samples. Thermal simulated luminescence study further indicated that the enhancement of afterglow property of Li 2 Ca 0.4 Sr 0.6 SiO 4 :Eu 2+ , Dy 3+ phosphor was due to the increased trap concentration resulting from the incorporation of Dy 3+ ions. The afterglow mechanism of Li 2 Ca 0.4 Sr 0.6 SiO 4 :Eu 2+ , Dy 3+ is illustrated and discussed in detail on the basis of experimental results. [ABSTRACT FROM AUTHOR]

A novel green emitting long afterglow phosphor Li 2 Ca 0.4 Sr 0.6 SiO 4 :Tb 3+ was obtained via a high temperature solid-state reaction in air atmosphere. X-ray diffraction (XRD), photoluminescence spectroscope (PLS), long afterglow spectroscope (LAS) and thermal luminescence spectroscope (TLS) were performed to characterize the physical properties of the phosphors. Typical 5 D 4 - 7 F j transitions of Tb 3+ ions were detected by PL spectra, corresponding to CIE chromaticity coordinates of x =0.3456, y =0.5745. An optimal concentration of Tb 3+ in the substrate was determined as 0.8 at%. The Li 2 Ca 0.4 Sr 0.6 SiO 4 phosphors showed a typical afterglow behavior when the UV source was switched off. A typical triple exponential decay behavior was confirmed after fitting the experimental data. Thermal simulated luminescence study further indicated that the afterglow behavior of Li 2 Ca 0.4 Sr 0.6 SiO 4 :Tb 3+ phosphors was generated by the recombination of electrons with the holes resulted from the doping of rare-earth ions (Tb 3+ ) in Li 2 Ca 0.4 Sr 0.6 SiO 4 host. The long afterglow luminescence mechanism of Li 2 Ca 0.4 Sr 0.6 SiO 4 :Tb 3+ is illustrated and discussed in detail on the basis of experimental results. [ABSTRACT FROM AUTHOR]

Laser powder bed fusion (LPBF) process is a promising additive manufacturing technique to manufacture multi-material integrated parts with complex structures. In this paper, the multi-material structure of Ti6Al4V/AlSi10Mg is fabricated by LPBF, the interfacial characterization, interfacial reaction mechanism and mechanical properties of Ti/Al structure are investigated. Results show that continuous and excellent metallurgical bonding between Ti6Al4V and AlSi10Mg is obtained, and the width of interface zone is about 100 μm. The equiaxed grains of aluminum alloy at the interface show random crystallographic orientation, which is attributed to the thermal dynamics in the melt pool, thermal cycles during LPBF process and lower thermal conductivity of titanium alloy. The interfacial reaction layers are orderly from titanium alloy to the aluminum alloy consisting of Ti 3 Al, TiAl with nanoparticles Ti 5 Si 3 and rod-like TiAl 3. The segregated Si atoms react with the dissolution of Ti atoms in-situ to form Ti 5 Si 3 , meanwhile, a mass of Al atoms also react with Ti atoms to form TiAl. Namely, the TiAl phase forms in thin layer shape embedded with nanoparticles Ti 5 Si 3 through eutectic reaction near the fusion line at the interface. At the wall of eutectic production, the TiAl 3 phase nucleation and grow opposite to the heat dissipation direction and vertical to the fusion line. Outside the fusion line, the supersaturated solid α-Ti transforms to Ti 3 Al through the diffusion of Al atoms in the part of titanium alloy. During the interfacial reaction, in-situ generated nanoparticles Ti 5 Si 3 could improve the joint strength, and the tensile strength of Ti6Al4V/AlSi10Mg specimens reached 264.8 ± 22.4 MPa. The tensile specimens exhibit brittle fracture and two typical fracture morphologies appear on the fracture surface. • Ti/Al samples were fabricated by laser powder bed fusion (LPBF), and the microstructure at the interface was affected by the extremely fast cooling rate and thermal cycles of LPBF • The interfacial phases are formed by different mechanisms and they are orderly from titanium alloy to the aluminum alloy consist of Ti 3 Al, TiAl with nanoparticles Ti 5 Si 3 and rod-like TiAl 3. • The tensile strength of Ti/Al specimens reached 264.8 ± 22.4 MPa due to the in-situ generated nanoparticles Ti 5 Si 3. [ABSTRACT FROM AUTHOR]

A novel green emitting long afterglow phosphor, Er 3+ -doped Ca 2 SnO 4 (Ca 2 SnO 4 :Er 3+ ), was prepared successfully via a traditional high temperature solid–state reaction method. Its properties have been characterized and analyzed by utilizing x-ray diffraction (XRD), photoluminescence spectroscope (PLS), afterglow decay curve (ADC) and thermal luminescence spectroscope (TLS). Three main emission peaks of PLS locate at 524, 550 and 668 nm, corresponding to CIE chromaticity coordinates of x = 0.326, y = 0.6592. An optimal doping concentration of Er 3+ of 2% was determined. The Ca 2 SnO 4 :Er 3+ phosphors showed a typical triple-exponential afterglow decay behavior when the UV source was switched off. Thermal simulated luminescence study indicated that the persistent afterglow of Ca 2 SnO 4 :2 mol% Er 3+ phosphors was generated by the suitable electron or hole traps which were resulted from the doping the Ca 2 SnO 4 host with rare-earth ions (Er 3+ ). [ABSTRACT FROM AUTHOR]

Ni modified spinel Li 3 Ti 4 NiCrO 12 (Ni/Li 3 Ti 4 NiCrO 12 ) anode material was synthesized by a simple high temperature solid-state reaction in a reducing atmosphere. The existence of metallic Ni not only changes the growth manner of the synthesized Ni/Li 3 Ti 4 NiCrO 12 , but also reduces the grain size, which further leads to a significant improvement in electric conductivity. Such Ni modified Li 3 Ti 4 NiCrO 12 anode material showed excellent electrochemical behavior upon cyclic test, with a high initial capacity of 158.8 mA h/g and high capacity retention (97.2%) after 80 cycles. All the results confirmed the significance of metallic Ni in promoting the electrochemical behaviors of Li 3 Ti 4 NiCrO 12 , suggesting high potential of Ni/Li 3 Ti 4 NiCrO 12 in future application. [ABSTRACT FROM AUTHOR]

Nowadays, Ni-rich cathodes act as a strong contender for high performance lithium-ion batteries cathodes due to their high capacities. Rapid capacity degradation and poor rate performance at high working voltages hinder their commercialization. This study reports a strategy for Ta5+ doping modification in LiNi 0.90 Co 0.04 Mn 0.03 Al 0.03 O 2 (NCMA) cathode via a solid-state route. This study confirmed that the introduction of strong Ta–O bond is beneficial to degrade H2–H3 phase transition during cycling. Subsequently, the polarization of electrodes and internal resistance have been alleviated since the H2–H3 phase transition of the Ta-doped NCMA cathode is suppressed, which eventually leads to a high cyclability. Moreover, it also confirmed that the diffusion of Li ions has been accelerated since the space of Li layer is enhanced. As a consequence, the Ta-NCMA cathode displays a high initial discharge capacity of 222.6 mA h·g−1 and outperforms the benchmarking cathodes in 100th capacity retention (from 43.7% to 91.8%) between 2.8 and 4.5 V. Besides, compared to pristine NCMA cathodes, the rate capability of Ta5+-doped NCMA cathodes cycling at 5C also increase from 112.2 mA h·g−1 to 167.2 mA h·g−1. Hence, Ta doped Ni-rich cathode should be a potential cathode to realize both high capacity and stability structure. [ABSTRACT FROM AUTHOR]

Inconel 718 superalloy has been fabricated by selective laser melting technology (SLM). Its microstructure and mechanical properties were studied under solution+aging (SA) standard heat treatment, homogenization+solution+aging (HSA) standard heat treatment and as-fabricated conditions. Precipitated phases and microstructures were examined using OM, SEM, TEM and X-ray analysis methods. The fine dendrite structures with an average dendrite arm spacing of approximately 698 nm accompanying some interdendritic Laves phases and carbide particles can be observed in the as-fabricated materials. After standard heat treatments, dendrite microstructures are substituted by recrystallization grains, and Laves phases also dissolve into the matrix to precipitate strengthening phases and δ particles. The test values of all specimens meet Aerospace Material Specification for cast Inconel 718 alloy, and the transgranular ductile fracture mode exists for the three conditions. The strength and hardness of heat-treated SLM materials increase and are comparable with wrought Inconel 718 alloy, whereas their ductility decreases significantly compared with the as-fabricated material. This is because of the precipitation of fine γˊ and γ〞strengthening phases and needle-like δ phases. For the as-fabricated alloy, the formation of finer dislocated cellular structures that develop into a ductile dimple fracture shows excellent ductility. Due to dislocation pinning from γˊ and γ〞strengthening phases and the impediment of dislocation motion caused by the needle-like δ phases, the ductility of the SA materials decreases and causes a transgranular fracture, compared with the as-fabricated samples. [ABSTRACT FROM AUTHOR]

This paper reports the photoluminescence and afterglow behavior of Dy 3+ in Ca 2 SnO 4 matrix (Dy 3+ :Ca 2 SnO 4 ) prepared via a solid-state reaction. X-ray diffraction (XRD), photo luminescence spectroscope (PLS) and thermal luminescence spectroscope (TLS) were performed to investigate the physical properties of the phosphors. Typical 4 F 9/2 to 6 H j energy transition of Dy 3+ ions was detected by PL spectra. CIE chromaticity coordinates of x = 0.4319, y = 4.456, calculated from the emission spectra, confirmed a yellow light emitting of the Dy 3+ :Ca 2 SnO 4 phosphors. The Ca 2 SnO 4 phosphors showed a typical afterglow behavior when the UV source was switched off. Thermal simulated luminescence study indicated that the persistent afterglow of Dy 3+ :Ca 2 SnO 4 phosphors was generated by the suitable electron or hole traps which was resulted from the doping the Ca 2 SnO 4 host with rare-earth ions (Dy 3+ ). [ABSTRACT FROM AUTHOR]

Li 4 Ti 5 O 12 − x anode powder containing oxygen vacancies was synthesized via ball-milling assisted solid-state reaction between LiOH⋅H 2 O, TiO 2 and graphene oxide as reactants. Different from previous reports, graphene oxide played the role of reducing agent in promoting the conversion of Ti(IV) into Ti(III) during the calcination process, the process is accompanied by the formation of oxygen vacancies. This assumption was confirmed by XPS and EPR results. SEM, TEM and Raman shows there is a small amount of residual graphene in the material, but the content of carbon is only 0.026%. The lithium-ion diffusion coefficient of oxygen-deficient Li 4 Ti 5 O 12 − x is calculated to be 1.02 ⋅ 10 −12 cm 2 s −1 , ten times higher than 1.61 ⋅ 10 −13 cm 2 s −1 for pure Li 4 Ti 5 O 12 . As a result, the as-prepared Li 4 Ti 5 O 12 − x exhibits excellent electrochemical performance, presenting an initial discharge capacity of 172.4 mA h g −1 at 0.5 C with a capacity retention of 96.7% over 100 cycles. [ABSTRACT FROM AUTHOR]

Tunable photoluminescence of Tb 3+ -doped LiMgPO 4 (Tb 3+ :LiMgPO 4 ) phosphors with different Tb 3+ concentrations are successfully synthesized by a high temperature solid-state reaction routine. X-ray diffraction (XRD) and photoluminescent spectroscope (PLS) are employed to characterize the phosphors. It is found that a suitable firing temperature is important for the synthesis of the phosphors, and pure phase material can only be obtained around 900 °C. PL spectra reveals typical 5 D 4 to 7 F j energy transition of Tb 3+ ions, and the emission colors varied from red to green with Tb 3+ concentration increasing, which is caused by the concentration quenching of Tb 3+ emission centers in the LiMgPO 4 matrix. The emissions peaking at 591, 619 and 695 nm are quenched at concentration of 1.5%, while the emissions at 489 nm and 543 nm are quenched at concentration of 8%. Further analysis of the data reveals two different energy transfer mechanisms for the five emission bands. The dipole–dipole model is proposed for the energy transfer of the red bands peaking at 694 nm, 619 nm and 591 nm, while the exchange interaction model is suggested for that of the green bands (543 nm and 489 nm), due to the different ion separations caused by different Tb concentrations. [ABSTRACT FROM AUTHOR]

Two different LiFePO 4 microplates grown in parallel with (010) and (001) lattice planes were obtained using a controllable hydrothermal process. The as-synthesized materials were characterized physically and electrochemically. XRD, SEM and HRTEM investigations confirmed the preferred growth and two corresponding growth mechanisms based on nucleation and recrystallization process were proposed. The calculation of Li ion diffusion coefficient along [001] and [010] directions using CV and EIS results revealed that (010) microplates have a higher diffusion coefficient than the (001) ones, implying a good electrochemical performance for (010) microplates over the (001) ones. Capacity tests confirmed the above assumption. Both the two cathode materials showed high specific capacities, and the (010) microplates exhibit a value around 158 mAh g −1 at a rate of 0.5C, showing a great advantage of (010) microplates for future application in LIBs for EV application. [ABSTRACT FROM AUTHOR]

Cell migration is a dynamic process that is central to a variety of physiological functions as well as disease pathogenesis. The modulation of cell migration by p27 (officially known as CDKN1B) has been reported, but the exact mechanism(s) whereby p27 interacts with downstream effectors that control cell migration have not been elucidated. By systematically comparing p27+/+ mouse embryonic fibroblasts (MEFs) with genetically ablated p27-/- MEFs using wound-healing, transwell and time-lapse microscopic analyses, we provide direct evidence that p27 inhibits both directional and random cell migration. Identical results were obtained with normal and cancer epithelial cells using complementary knockdown and overexpression approaches. Additional studies revealed that overexpression of manganese superoxide dismutase (MnSOD, officially known as SOD2) and reduced intracellular oxidation played a key role in increased cell migration in p27-deficient cells. Furthermore, we identified signal transducer and activator of transcription 3 (STAT3) as the transcription factor responsible for p27-regulated MnSOD expression, which was further mediated by ERK- and ATF1-dependent transactivation of the cAMP response element (CRE) within the Stat3 promoter. Collectively, our data strongly indicate that p27 plays a crucial negative role in cell migration by inhibiting MnSOD expression in a STAT3-dependent manner. [ABSTRACT FROM AUTHOR]

• A 10 wt% SiC-reinforced AlSi10Mg-based composites with higher density is prepared by selective laser melting. • Al4SiC4 phase forms because the in situ reaction between SiC and Al melt occurs. • The SLM-fabricated AlSi10Mg-10SiC composite (90.64 J/mm3) displays the high yield strength (408 Mpa) and modulus (90 Gpa). In this study, a 10 wt% SiC-reinforced AlSi10Mg-based composites is prepared by selective laser melting (SLM) process. The effect of laser linear energy density on phase morphology, microstructure, and mechanical properties of AlSi10Mg-10SiC composite is investigated. There is relatively higher density, no obvious pores and cracks in the SLM-fabricated AlSi10Mg-10SiC composites with laser linear energy densities ranging from 90.64 J/mm3 to 104.16 J/mm3. The high laser linear energy density promotes the in-situ reaction between SiC particle and Al melt in the melt pool, the Al4SiC4 phase forms during SLM fabrication process. Driven by Marangoni convection, the fine SiC particles and Al4SiC4 phase distributes uniformly. When the laser linear energy density is 104.16 J/mm3, the composite exhibits the highest average microhardness of 208.5 HV 0.1. When the laser linear energy density is 90.64 J/mm3, the composite displays the highest yield strength and modulus with values of 408 MPa and 90 Gpa, respectively. During the deformation process of tensile test, the higher modulus SiC particles could withstand greater load transfer, which improves the modulus and yield strength of the composites. [ABSTRACT FROM AUTHOR]

Abstract: The electronic structures of a LiFePO4 (010) surface adsorbed with C are studied by a first-principles method based on DFT. The results show that the system is more stable when the LiFePO4 (010) surface is cut through Li atoms. PDOS analysis shows that the electronic structure of atoms in the sub-surface is similar to that of atoms in the bulk. The unpaired electrons in Fe-d orbital play a key role in the changes in the microelectronic structure; these changes lower the band gap and generate new bands that favor the transfer of electrons. Atom C reacts with Fe by chemisorptions when C is adsorbed on the outermost layer. Therefore, the materials may have better electrochemical properties by the improvement of diffusion of both electrons and Li ions when limiting the crystal growth with C coating. [Copyright &y& Elsevier]

Herein, redshifted long persistent LiMg x Sr 4- x -2 y (BO 3) 3 : y Eu2+, Dy3+(Nd3+) phosphors are successfully prepared in a reducing atmosphere using a high-temperature solid-state process. The emission of phosphors displays redshift characteristics between 633 and 660 nm with an increase in the concentration of Mg2+ substitution, primarily attributed to enhanced energy level splitting of Eu2+ after Mg2+ replacement. The afterglow performance of LiMg 0.6 Sr 3.4-2 y (BO 3) 3 : y Eu2+, Dy3+ (Nd3+) samples is enhanced with increase in concentrations of the doped rare-earth ions. An optimal concentration of 6%, the best afterglow performance was achieved because high concentration traps with suitable energy levels were developed; this was confirmed using afterglow measurements and thermoluminescence tests. The Nd3+ codoped phosphor shows improved afterglow performance compared with the Dy3+ codoped phosphor at the same doping concentration, which can be attributed to Nd3+ can easily be incorporated into the borate lattice that generates electron traps with high concentration. [ABSTRACT FROM AUTHOR]

Abstract: Molecular dynamics technique has been employed to investigate the relationship between the intrinsic structure and transport properties of lithium ions in LiFePO4 cathode materials. The results show that it is more favorable for Li ion diffusion when crystalline LiFePO4 grows along specific [100] directions, which may cause higher lithium diffusivity through a one dimensional [010] migration path. The change of Li ion diffusivity with temperature reveals that higher temperatures result in higher disorder of the atoms (or ions) and makes Li–O bonding relatively weaker, suggesting that Li diffusion is influenced by the microstructure of LiFePO4, particularly the bonding strength between Li and O atoms. [Copyright &y& Elsevier]

Abstract: LiFePO4 has become a highly promising cathode material for use in the next generation of lithium-ion batteries, in which metal-doping is typically employed to improve the electrochemical properties. However, it is always difficult to resolve the issue that how the doping element and its position cause the microstructural changes and eventually influence the material properties. In this work, the X-ray diffraction (XRD) patterns of a series of metal-doped LiFePO4 were simulated by software MS Reflex to investigate those factors since XRD is a typical technique for the study of crystal structures. The effect of simulation conditions, doping position, and types of doping elements were discussed. The results revealed that: (1) the suitable step size should be 0.02° or less, and the simulation position had little influence on the XRD pattern; (2) the peak intensity changed with doping position, and had been affected more evidently at the Li-site compare with the Fe-site; (3) there was a close relationship between the doping elements and peak intensities in XRD patterns, and the variation degree of the peak intensity increased linearly with the atomic number of doping elements. [ABSTRACT FROM AUTHOR]

Abstract: Arsenic is a well-documented human carcinogen associated with skin carcinogenesis. Our previous work reveals that arsenite exposure is able to induce cell transformation in mouse epidermal cell JB6 Cl41 through the activation of ERK, rather than JNK pathway. Our current studies further evaluate downstream pathway in low dose arsenite-induced cell transformation in JB6 Cl41 cells. Our results showed that treatment of cells with low dose arsenite induced activation of c-Jun/AP-1 pathway, and ectopic expression of dominant negative mutant of c-Jun (TAM67) blocked arsenite-induced transformation. Furthermore, our data indicated that cyclin D1 was an important downstream molecule involved in c-Jun/AP-1-mediated cell transformation upon low dose arsenite exposure, because inhibition of cyclin D1 expression by its specific siRNA in the JB6 Cl41 cells resulted in impairment of anchorage-independent growth of cells induced by low dose arsenite. Collectively, our results demonstrate that c-Jun/AP-1-mediated cyclin D1 expression is at least one of the key events implicated in cell transformation upon low dose arsenite exposure. [Copyright &y& Elsevier]

It is well-known that insoluble nickel compounds possess much more potent carcinogenic activities as compared with soluble nickel compounds. Although it is assumed that the different entry and clearance rate are responsible for the difference, the mechanisms underlying the different carcinogenic activities are still not well understood yet. In the present study, we found that exposure to soluble, but not insoluble nickel compounds, caused a significant inhibition of cell growth and G1/G0 cell cycle arrest, which was concomitant with a marked down-regulation of cylin D1, an essential nuclear protein for controlling G1/S transition, while both soluble and insoluble nickel compounds showed similar effects on NFκB activation, HIF-1α protein accumulation and TNF-α transcription and CAP43 protein expression at same doses range. The down-regulation of cyclin D1 is due to protein degradation rather than inhibition of transcription, because the nickel compounds treatment did not change cyclin D1 mRNA level, while MG132, the proteasome inhibitor, can rescue the degradation of cyclin D1 caused by soluble nickel compound. Moreover, the soluble nickel-induced cyclin D1 degradation is dependent on its Thr286 residue and requires IKKα, but not HIF-1α, which are both reported to be involved in cyclin D1 down-regulation. Taken together, we demonstrate that soluble, but not insoluble nickel compound, is able to cause cyclin D1 degradation and a cell growth arrest in an IKKα-dependent manner. Given the role of cyclin D1 and cell proliferation in carcinogenesis, we anticipate that the different effects of soluble and insoluble nickel compounds on cyclin D1 degradation and cell growth arrest may at least partially account for their different carcinogenic activities. J. Cell. Physiol. 218: 205–214, 2009. © 2008 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Recent studies from our laboratory have shown that the transactivation of nuclear factor κ B (NFκ B) and activator protein-1 (AP-1) plays an important mechanistic role in ultraviolet (UV)-induced skin carcinogenesis in mice. We also demonstrated that a methanol extract (ME) fraction from black raspberries (Rubus occidentalis) (RO; RO-ME) inhibits benzo[a]pyrene-7,8-diol-9,10-epoxide [B(a)PDE]—induced activation of NFκ B and AP-1 in cultured mouse epidermal cells. In the present study, we determined if RO-ME might also inhibit the induction of NFκ B and AP-1 in mouse epidermal cells exposed to mid UV radiation (UVB) and short UV radiation (UVC) and whether methanol fractions from strawberries and blueberries would also be effective. Our results showed that RO-ME inhibited UVB-induced activation of NFκ B in mouse epidermal cells in a time- and dose-dependent manner; however, the methanol fractions from strawberries and blueberries were ineffective. Interestingly, none of the fractions from all 3 berry types inhibited UVB- or UVC-induced activation of AP-1, suggesting that inhibition of UV-induced signaling pathways is specific for black raspberries and NFκ B. Cyanidin-3-rutinoside, an anthocyanin found in abundance in black raspberries and not in strawberries or high-bush blueberries, was found to contribute to the inhibition of UVB-induced activation of NFκ B. These results suggest that berries differ in their ability to influence signaling pathways leading to activation of NFκ B and AP-1 when using UV light as the inducer. [ABSTRACT FROM AUTHOR]

• The microstructure of TA15 fabricated by laser powder bed fusion (LPBF) was studied and the formation mechanism of martensite classification was mainly explained. • The influence of different heat treatment temperatures on evolution of microstructure, mechanical properties and fracture mechanism were studied. • The sample after heat treatment at 940 °C obtains excellent comprehensive mechanical properties, because the quartic acicular α phases precipitate in the transformed β phase. TA15 titanium alloy has been widely used in the aerospace industry due to its moderate high-temperature performance. In this research, TA15 samples with excellent mechanical properties were successfully fabricated by laser powder bed fusion (LPBF). Results show that the microstructure of TA15 sample is composed of acicular α′ martensites within the columnar prior β grain. During manufacturing process of LPBF, the non-equilibrium heating and cooling of the thermal cycles experiencing different peak temperatures result in the hierarchical structure of martensite. After heat treatment at 750 °C, 840 °C, 900 °C, and 940 °C for two hours, the fine martensitic structure has transformed into a mixture of α and β. With the increase of temperature, the volume fraction of β increases from 10.3% to 49.9%, the width of primary α increases from 0.72 ± 0.16 µm to 2.96 ± 0.17 µm because of the simultaneous fragmentation of the primary α. So the ultimate and yield strengths decrease while the elongation increases. After heat treatment at 940 °C, the specimen shows the best comprehensive mechanical properties, the elongation increases to 11.5%, the tensile strength is 1061 MPa, and the yield strength is 961 MPa. The fracture surface shows the typically ductile fracture character. [ABSTRACT FROM AUTHOR]

A strategy to enhance the electrochemical performance of a single-crystal LiNi x Mn y Co z O 2 (NCM) electrode is proposed herein based on a preferred orientation of a Li diffusion pathway along the working direction under an ordinary 0.4-T magnetic field. Hexagonal NCM622 single crystals can be aligned along their crystallographic c-axis parallel to the applied magnetic field because the crystal has an easy magnetization axis along the c-axis. The horizontal magnetic field–oriented NCM622 cathode (HMFC) shows inhibited polarization and increased lithium-ion conductivity. The suppressed polarization promotes cyclability, increasing the specific capacity from 157.93 to 168.75 mAhg−1 after the 100th cycle at 0.5 C. Furthermore, the increased diffusion coefficient (from 3.06 × 10−10 cm2s−1 to 7.12 × 10−10 cm2s−1) causes substantial improvement in the rate performance, achieving a high specific capacity of 130.77 mAhg−1 at 10 C, while the electrode without magnetic treatment achieves a specific capacity of only 115.88 mAhg−1. Owing to such a superior electrochemical performance, the HMFC electrodes show high potential for lithium-ion batteries in the EV industry. Decreasing the magnetic field from 6 to 0.4 T for cathode alignment facilitates the applicability of the proposed strategy to production lines of battery plants using commercially available permanent magnets because a magnetic field of 0.4 T is easily achievable. [Display omitted] [ABSTRACT FROM AUTHOR]

Vat photopolymerization 3D printing provides a novel approach for preparing broadband wave-transparent Si 3 N 4 /β-SiAlON composite ceramics. This paper oxidized raw powder to introduce low dielectric phases (SiO 2) and overcome the low curing depth of α-Si 3 N 4. The solid content of oxidized α-Si 3 N 4 was increased to 50 vol% for the first time by modification with dispersant. The selected print thickness of 50 μm was the highest known for Si 3 N 4 vat photopolymerization 3D printing, greatly improving printing efficiency. Finally, Si 3 N 4 /β-SiAlON composite ceramics were sintered in the range of 1600-1800 °C, and the mechanical and dielectric properties were systematically studied. The composite ceramics sintering at 1780 °C had a maximum bending strength of 236 ± 16 MPa, and the real permittivity was 4.83. At 1800 °C the porosity increased resulting in bending strength decreased to 109 ± 4 MPa, and the real permittivity to 3.23. This study filled the gap in the post-treatment of oxidized α-Si 3 N 4 and guided the application of Si 3 N 4 /β-SiAlON composite ceramics in the field of wave-transparent. [ABSTRACT FROM AUTHOR]

Microstructure, mechanical performances at elevated temperature (650 °C) and their correlation of Inconel 718 manufactured by Selective Laser Melting (SLM) were investigated in this paper. Four kinds of heat treatment schemes including homogenization, solution treatment and conventional aging process were carried out to regulate the microstructure in order to obtain the optimum comprehensive mechanical performances at high temperature. The dimension and morphology of grains, subgrains, different precipitates including δ phase, strengthening phase, carbides and nitrides were investigated. In addition, their evolution mechanism was also analyzed in detail. Furthermore, for figuring out the effects of microstructures on the mechanical performance, creep rupture test and tensile test were carried out to compare the performance differences of heat-treated samples. The results demonstrated that the heat-treated samples show the better creep rupture performance and higher tensile strength at elevated temperature than that of the wrought. In addition, the sample under homogenization heat treatment in 1080 °C, solution treatment in 980 °C and conventional aging treatment shows the optimum mechanical properties at 650 °C. [ABSTRACT FROM AUTHOR]

The present study was designed to investigate the potential role and the mechanism of equilibrative nucleoside transporter 1 (ENT1) on neuronal apoptosis and neurological deficits after middle cerebral artery occlusion (MCAO) in rats. One hundred and thirty-four male Sprague-Dawley rats were subjected to two hours of MCAO followed by reperfusion. The time course of the expression level of ENT1 and phosphorylation of CREB were detected by western blot and immunofluorescence staining. Another set of animals were administrated with NBTI, the ENT1 inhibitor, by daily intraperitoneal injection starting at 0.5 h post-MCAO, infarction volume and neurological deficits were measured both at 24 h and 72 h post MCAO. We further explored the neuroprotection machenism by using H89, cAMP dependent protein kinase inhibitor, the expression of Bcl-2, Bax, phosphorylated CREB and Cleaved caspase-3 were quantified by Western blot, neuronal apoptosis were analyed by TUNEL staining. The endogenous expression of ENT1 were significantly increased and peaked at 12 h after MCAO. High-dose of NBTI (15 mg/kg) reduced brain infarction volume and improved neurologic deficits both at 24 h and 72 h post MCAO. Moreover, NBTI significantly increased the level of CREB phosphorylation and extracellular adenosine concentration, and decreased the neuronal apoptosis 24 h after MCAO. NBTI treatment reduced the expression of Bax and cleaved caspase-3, while up-regulated Bcl-2 compared with vehicle group. These effects were abolished by H89 pretreatment. ENT1 inhibition prevented neuronal apoptosis and improves neurological deficits through cAMP/PKA/CREB/Bcl-2 signaling pathway after MCAO in rats. ENT1 might be an effective target in the treatment strategy for ischemic stroke. • The expression time course of equilibrative nucleoside transporter (ENT1) after MCAO in rats • ENT1 inhibitior NBTI(15 mg/kg) reduced infarct volume and improved neurological function 24 and 72 hours after MCAO • NBTI treatment reversed the depletion of extracellular adenosine concentration and CREB phosphorylation after MCAO • NBTI treatment prevented neural apoptosis though the cAMP/pCREB/Bcl2 signal pathway [ABSTRACT FROM AUTHOR]

The hypothalamic–pituitary–adrenal (HPA) axis plays a critical role in adaptive stress responses and maintaining organism homeostasis. The pituitary corticotroph is the central player in the HPA axis and is regulated by a plethora of hormonal and stress related factors that synergistically interact to activate and temper pro-opiomelanocortin (POMC) transcription, to either increase or decrease adrenocorticotropic hormone (ACTH) production and secretion as needed. Nuclear receptors are a family of highly conserved transcription factors that can also be induced by various physiologic signals, and they mediate their responses via multiple targets to regulate metabolism and homeostasis. In this review, we summarize the modulatory roles of nuclear receptors on pituitary corticotroph cell POMC transcription, describe the unique and complex role these factors play in hypothalamic–pituitary–adrenal axis (HPA) regulation and discuss potential therapeutic targets in disease states. [ABSTRACT FROM AUTHOR]

As-Selective Laser Melted (as-SLMed) Ti6Al4V in horizontal direction possess poor ductility because of acicular α ' martensite and columnar β grains in microstructure. However, traditional ductility improvement methods including high-temperature preheating or heat treatment will decrease not only strength but also the efficiency of SLM fabrication to application. For a satisfactory mechanical property of as-SLMed Ti6Al4V alloy, some special temperature evolution conditions brought about from processing parameters such as layer thickness, hatch spacing, energy density and area ratios between support structure and part, were carried out in the paper. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to characterize the microstructure. The microstructure of as-SLMed specimens are found to be different extent decomposing of α ' martensite. Also, the formation mechanisms of such microstructural variables are proposed based on temperature evolution vs time during SLM process. Moreover, the tensile test presents high elongation (>8%) is achieved for horizontally as-SLMed Ti6Al4V specimens without lowering their strength (the ultimate tensile strength ∼ 1260 ± 30 MPa and yield strength ∼1160 ± 50 MPa), which markedly exceed ASTM standard for castings. The mechanical properties and fracture mechanisms of specimens are obviously affected by the width of α ' / α martensite and the content of β phase. This work marks an important step forward in the understanding of microstructural tailoring in SLM process for a high-performance Ti6Al4V alloy. • Three types microstructures that full α′ martensite, α'+(α+β) and (α+β) can be tailored by special SLM conditions. • Microstructural formation mechanism was studied to further understand mechanical properties. • The as-SLMed Ti6Al4V exhibits improved elongation without decreasing strength. [ABSTRACT FROM AUTHOR]

The paper studies comparatively on the microstructures and mechanical performances at elevated temperature of SLM-fabricated Inconel 718 alloy in as-build, SHT 980, SHT 1080, SHT 980 + 1080 heat treated conditions. The morphology and distribution of δ phase in the γ matrix are regulated by pre-designed heat treatment schemes, their effects on tensile properties and stress rupture properties at elevated temperature are discussed. The results show that the specimens of SLM-fabricated Inconel 718 alloy in SHT 980 + 1080 heat treated conditions possess the optimum mechanical performances at elevated temperature, in which the morphology and distribution of δ phase in the γ matrix are the key factors in determining their high temperature performances. The excessive δ phases within grains and along grain boundaries can easily lead to dislocation piling up in the process of tensile test at elevated temperature, causing local stress concentration and microcrack generation in the matrix, further initiating premature failure of parts. However, lack of δ phase will reduce the high temperature strength of grain boundaries and then influence the high temperature mechanical properties. As a result, the suitable heat treatment is used to regulate the precipitation of δ phase and the moderate amount of δ phases precipitate along grain boundaries, further improving high temperature mechanical properties of IN718 alloy. [ABSTRACT FROM AUTHOR]

Summary: To improve the electrochemical performances of high voltage LiCoMnO4 spinel cathode material at 5.3 V, Cr doped LiCoMn1‐xCrxO4 (x = 0, 0.025, 0.050, 0.075) materials were synthesized by a one‐step solid‐state at 750°C. Rietveld refinement results showed that the phase purity of spinel is promoted with the increase in Cr concentration, which can be explained by the strong CrO bond that reduces oxygen deficiency and eliminates Li2MnO3 impurity phase during the synthesis process. Such change in phase purity further causes the improvement in specific capacity, and the 5.0%Cr doped sample displays the best result with a value of 123.0 mAh/g at 0.1°C and 93.3 mAh/g at 10°C. For a comparison, the pristine sample only releases a capacity of 112.6 mAh/g at 0.1°C and 54.8 mAh/g at 10°C. Improved capacity retention, from 83.1% to 90.1% after 100 cycles at 1°C, is also observed due to the suppressed volume change during the redox process after the incorporation of Cr cations in the lattice. Promoted rate performance, attributed from the improved Li ion diffusion coefficient, is also confirmed in the experiment. The improvement of those electrochemical properties could be explained by high‐phase purity and superior structural stability benefited from Cr‐doping. Novelty statement: LiCoMn1‐xCrxO4 (x = 0, 0.025, 0.050, 0.075) materials were synthesized by a one‐step solid‐state at 750°C, Chromium had been confirmed to reduce oxygen loss during LiCoMnO4 synthesis due to high oxygen affinity of Cr, which improves phase purity. As a result, the specific capacity was increased. Cr‐doping enhances the structural stability so that capacity retention was promoted due to higher bond energy of CrO than MnO; rate performance was also enhanced due to the improved diffusion coefficient. [ABSTRACT FROM AUTHOR]

High nickel cathode material LiNi 0.85 Co 0.10 Al 0.05 O 2 (NCA) has attracted public attention because of its high energy density and low cost in production, but the material also faces the problem of rapid capacity decay due to the phase transition upon redox process. In this study, the co-modification with Na and Nb cations is employed to stabilize the lattice and promote the electrochemical behavior of the NCA material upon the application at 4.5 V. X-ray diffraction (XRD) investigations show that the co-modification of Na and Nb in the lattice reduces the disordering of the lattice and suppresses the volume change during the redox process, thereby increasing the specific capacity and the cyclic performance for the NCA material upon 4.5 V application. The Co-doped sample presents a specific capacity of 212.5 mAh/g when cycled 0.1 C, together with a capacity retention of 94.3% at 0.5 C after 100 cycles. This shows an obvious promotion when compared to that of undoped one (208.7 mAh/g and 78.2%). Furthermore, at a current density of 5 C, the Co-doped sample displays a high specific capacity of 152.2 mAh/g, while the value for the pristine NCA is only 129 mAh/g. Such improvement in rate performance can be attributed to the increased diffusion coefficient (from 7.57 × 10−13 to 3.27 × 10−12 cm2 s−1) due to the expanded space of lithium slab after co-doping of Na and Nb. The Na–Nb co-doping approach in this report offers a simple route to provide cathode materials with improved cyclability and enhanced rate behavior, demonstrating high potential for commercial application. [ABSTRACT FROM AUTHOR]

[Display omitted] • Li 2 Ni 0.5 Mn 1.5 O 4 (LNMO) cathode releases a high capacity of 260.4 mAh g−1. • The surface of LNMO cathode is covered by a thin LBSO layer in this approach. • LBSO layer suppresses the increase in resistance and the degradation in Li diffusion. • Capacity retention is significantly improved by 14% due to the LBSO coating. A new spinel Li 2 Ni 0.5 Mn 1.5 O 4 (LNMO) cathode reported in our previous work displays high initial specific capacity (260.4 mAh g−1) and good coulombic efficiency (92.2%), but suffers from low capacity retention of 80.2% after 50 cycles. In this paper, Li 2 O-0.2B 2 O 3 -1.8SiO 2 (LBSO) glass phase surface modification is adopted to promote the electrochemical performance of LNMO. LBSO layer coated on the surface of LNMO cathode, as confirmed by SEM and HRTEM observation, can effectively prevent the cathode from dissolving in the electrolyte, therefore suppresses the increase in resistance and the degradation in Li-ions diffusion. Consequently, the electrochemical properties of the surface modified cathode material are improved. The initial specific capacity of 0.3 wt% LBSO coated LNMO is kept as 263 mAh g−1 with coulombic efficiency of 95%. Notably, the capacity retention after 100 cycles is improved from 69% to 83% by a comparison between the pristine and coated samples. Moreover, the coated cathode exhibits good rate performance, giving high specific capacity of 142 mAh g−1 even at a current density of 5C. All the results presented above suggest high potential for the material as candidate cathode for high energy density batteries. [ABSTRACT FROM AUTHOR]

Summary: This paper reports a feasible approach to offer LiNi0.8Co0.1Mn0.1O2 (NCM811) layered cathode materials with enhanced lattice ordering and improved electrochemical performance through a nano grinding assisted solid‐state reaction. Different from the commercial precursor method, oxide raw materials, NiO, CoO and MnO2, rather than the hydroxides, was employed as the starting raw material which was milled into submicron size, pressed into pellets and crushed into granular powder. After calcination under oxygen atmosphere under different temperature, such a simple approach provides layered cathode materials with controllable Li/Ni disordering. Powder XRD results show that when sintered at 800°C, a largest I(003)/I (104) ratio is observed, indicating that the cationic disordering is the lowest, as been confirmed by the XRD refinement data, showing that only 1.08% Ni is misplaced at 3b site. For the electrochemical test, the pNCM800 sample presented an initial specific discharge capacity of 203 mAh/g at 0.1C, together with a capacity retention of 91.77% after 100 cycles at 0.5C. Compared to the value of the sample obtained at normal routine (163.8 mAh/g and 74.85%), the improvement in electrochemical behavior is obvious. Furthermore, the rate performance is also improved, with a specific capacity of 144.1 mAh/g even at 5C rate. The reason for such enhancement could be ascribed to the better kinetic process with low interfacial resistance and fast Li diffusion contributed from the promoted lattice ordering. The results obtained in the experiments greatly indicate the significance of the approach in controlling the Li/Ni disordering, and thus offer an alternative routine for the mass production of layered cathode materials besides the so‐called precursor method. [ABSTRACT FROM AUTHOR]

Although the Ni-rich LiNi 0.8 Co 0.15 Al 0.05 O 2 (N85CA) material has been used as the commercial cathode of electric vehicle battery, the instability of the layered structure and the short lifespan under high voltage cycling prevent its practical application to higher energy density. Herein, Nb-doped N85CA material, with enhanced structural stability and improved cycle stability, is reported to work at 4.5V. In particular, Nb0.5%-N85CA shows the best electrochemical performance, with a discharge capacity of 200.2 mAh/g at 0.1C, and a retention of 94.19% after 100 runs at 0.5 C. As a comparison, the data of the pristine N85CA are 210.2 mAh/g and 69.46%, respectively. Such an obvious increase in the capacity retention is caused by the promoted lattice stability provided by the strong Nb–O bond that inhibits the H2–H3 phase transition in the electrochemical process. The incorporation of Nb5+ ions further increases the interslab thickness that enable a rapid migration of Li ions (2.23 × 10−10 S cm−1 vs. 8.32 × 10−11 S cm−1), and the rate behavior of the cathode is also enhanced. Furthermore, Nb0.5%-N85CA material displays a specific capacity of 156.2 mAh/g at 5 C, while that of the pristine N85CA is 123 mAh/g. The results strongly indicate that such Nb-doped N85CA material has high potential as a cathode candidate, especially for high energy applications. [ABSTRACT FROM AUTHOR]

It's well documented that over-production of reactive oxygen species (ROS) causes detrimental damages to cells. While a low level of ROS, such as H 2 O 2 , functions as signaling transducer and motivates cell proliferation in both cancer and non-transformed stem cells. As a double-edged sword, the direct evidence for demonstrating the function of H 2 O 2 in the cause of tumor is barely characterized in intact cells. In our current study, we found that targeted expression of mitochondrial catalase (mCAT), but not catalase, could significantly reduce the accumulation of H 2 O 2 in mouse epithelial JB6 Cl41 cells, consequently led to the cell malignant transformation and anchorage-independent cell growth. Further study revealed that this reduction of H 2 O 2 resulted in the translocation of nucleolin from the cytoplasm to nuclear, and maintaining the nucleolin nuclear location status, and in turn stabilizing the cox-2 mRNA and consequently leading to a COX-2 protein upregulation, as well as malignant transforming mCAT-overexpressed Cl41 cells. Collectively, our studies here provide direct experimental evidence demonstrating a novel function and molecular mechanisms of mCAT in transforming mouse Cl41 cells, and high significance insight into understanding the beneficial aspect of H 2 O 2 in circumventing tumor promotion and the theoretical basis for the management of H 2 O 2 in the clinic implementation as a chemotherapeutic strategy. [ABSTRACT FROM AUTHOR]

New anode materials (Co x /Li 3 Ti 4 Co 1−x CrO 12 ) had been successfully prepared via a high temperature solid-state method. Pure phase Co-Cr replaced solid solution (Li 3 Ti 4 CoCrO 12 ) was obtained by calcinating the precursor under air atmosphere while the Co modified solid solutions (Co x /Li 3 Ti 4 Co 1−x CrO 12 ) were prepared under a reducing atmosphere. Various methods, such as XRD, SEM, EDX mapping, cyclic testing, EIS, CV, XPS and EPR were employed to characterize the powder samples and investigate their electrochemical behavior. SEM results showed spherical shape of the products with nano sized primary crystals. EDX mapping further confirmed the different existence of the Co element, uniform distribution of Co 2+ ions within the spinel lattice and separated metallic Co on the particle surface. Cyclic tests revealed that the Co modified samples showed great promotion in their electrochemical performance. For the sample with x = 0.1, the best results with an initial capacity of 157.6 mA h/g and a capacity retention of 96.4% after 100 runs were observed. Such promotion can be explained by the improved electronic conductivity and enhanced Li + diffusion coefficient confirmed by the EIS and CV simulation, which was caused by the oxygen vacancy produced during the calcination under the reducing atmosphere. [ABSTRACT FROM AUTHOR]

This study presents a novel modification strategy involving the replacement of Mn with Sc in the cathode of NaNi 1/3 Fe 1/3 Mn 1/3 O 2 (NFM). The results of this study confirmed that Sc doping introduced strong Sc–O bonds to enhance the bonding between transition metal ions and O2−. Additionally, Sc doping reduced the proportion Mn3+ in the material (from 50.23% to 47.46%), thereby inhibiting the material structural distortion due to the Jahn–Teller effect induced by Mn3+. These factors were the main contributors to the improved cycling performance of the modified material. Furthermore, the introduction of Sc decreased the band gap of the material (1.7416–1.6706 eV) and the Na+ activation barrier energy (0.773–0.732 eV). These changes not noly facilitated the de-embedding of Na+ in the material lattice but also significantly enhanced the material electronic conductivity, leading to an excellent rate performance of the modified material. These results indicate that the NFM-Sc0.01 sample maintained an ultra-high capacity retention of 86.45% after 200 cycles at 1 C. At 5 C, the discharge capacity of NFM-Sc0.01 significantly increased from 79.3 mAh g−1 in NFM to 93.4 mAh g−1, demonstrating great potential for industrialized applications. • Sc3+ of stronger Sc-O binding energy was used to partally replace Mn in NFM. • Sc doping can inhibit NFM structural distortion caused by the Jahn-Teller effect. • Sc doping reduced the Na+ activation barrier energy from 0.773 to 0.732 eV. • The discharge capacity of NFM-Sc0.01 at 5 C was enhanced to 93.4 mAh g−1. [ABSTRACT FROM AUTHOR]

A long persistent phosphor LiSr 4 (BO 3) 3 : Eu2+, Dy3+ shows a typical 5d–4f transition of Eu2+ under ultraviolet activation with an emission centered at 632 nm. Herein, the lattice site of Sr2+ is partially replaced with Mg2+ and Ba2+ and co-doping is performed using Eu2+ and Dy3+ to successfully synthesize several LiSr 4− x Ba x (BO 3) 3 :2% Eu2+, Dy3+ and LiSr 4− y Mg y (BO 3) 3 :2% Eu2+, Dy3+ phosphors with multicolor luminescence using a high-temperature solid-phase approach. When x or y = 0.4, the samples exhibit bright yellow or orange–red luminescence under ultraviolet (UV) excitation, with the emission spectra showing blue (611–632 nm) or red (632–648 nm) shifts, respectively. Such shifts in the peak position are ascribed to the weakened or enhanced crystal field strength. Under UV excitation, an afterglow phenomenon is also observed. The afterglow profiles can be simulated using an empirical double decay model. The LiSr 3.76 Mg 0.2 (BO 3) 3 : 2% Eu2+, Dy3+ sample exhibits the best afterglow phenomenon, which is potentially attributed to the formation of numerous electron traps with suitable trap depths after the incorporation of Mg2+ into the phosphor lattice. [ABSTRACT FROM AUTHOR]