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The MCrAlY bonding layer alloy was prepared by vacuum melting, and the alloy composition was NiCoCrAlY and NiCoCrAlYHfTa. The high-temperature cyclic oxidation experiment was carried out in air at 1050∘C until it failed. The results show that Hf and Ta have a significant influence on the oxidation resistance of the alloy. The doped specimens have longer oxidation lifetimes compared to the undoped samples. The study also found that the Hf would diffuse out and combine with O to form HfO2 in the thermally grown oxide (TGO) layer, which would improve the adhesion and reduce the wrinkles of the oxide layer. Ta in the doped specimens hinders the diffusion of Al and reduces the oxidation rate, while improving the thermal mismatch. Therefore, the specimens doped with both Hf and Ta have the highest oxidation lifetimes, though the oxidation lifetime was 10 times longer than that of the undoped specimens. It is indicated that the doping of Hf and Ta is an important method to improve the oxidation lifetime of thermal barrier coatings (TBCs).

In this study, a substrate was surface textured using a femtosecond laser to prolong the service life of thermal barrier coatings (TBCs). The selected texture showed linear and diamond shapes. The effect of the texture shape on the thermal shock resistance of the TBCs was investigated by subjecting them to thermal shock cycles. The microstructure and composition of the TBCs were investigated using various characterisation methods. The mechanical properties of the TBCs were measured using the microindentation method. Based on the theory of elastoplastic mechanics, a three-dimensional finite element numerical model was established to analyse the effect of the two textures on the stress distribution of the TBCs. The results revealed that the linear-textured TBCs showed improved stress concentration at the coating interface when the coatings expanded or shrank, which resulted in an improvement in their thermal shock resistance. Therefore, the linear-textured TBCs showed excellent oxidation resistance, fracture toughness, and heat resistance as compared to the diamond-textured TBCs.

Hematologists evaluate alterations in blood cell enumeration and morphology to confirm the peripheral blood smear findings through manual microscopic examination. However, routine peripheral blood smear analysis is both time-consuming and labor-intensive. Here, we propose a smartphone-based autofluorescence microscopy (Smart-AM) system for imaging label-free blood smears at sub-cellular resolution and performing hematological analysis. Smart-AM enables rapid, high-quality, and label-free visualization of morphological features of different blood cells (leukocytes, erythrocytes, and thrombocytes) and abnormal variations in blood cells. Moreover, assisted with deep learning algorithms, this technique can automatically detect and classify different leukocytes with high accuracy, and transform the autofluorescence images into virtual Giemsa-stained images maintaining significant cellular features. The proposed technique is portable, cost-effective, and user-friendly, making it significant for broad point-of-care applications.

Lung cancer is one of the leading causes of cancer death worldwide. The diagnosis of lung cancer based on the analysis of formalin-fixed and paraffin-embedded (FFPE) tissues is laborious and time-consuming, failing to guide surgeons intraoperatively. Here we proposed a rapid histological imaging method, termed microscopy with ultraviolet single-plane illumination (MUSI), to enable rapidex-orin-vivoimaging of fresh and unprocessed tissues in a label-free and non-destructive manner. The MUSI system allows surgical specimens with large irregular surfaces to be screened at a speed of 0.5 mm2/s with a subcellular resolution, which is sufficient to provide immediate feedback to surgeons and pathologists for intraoperative decision-making. We demonstrate that MUSI can differentiate between different subtypes of human lung adenocarcinomas, revealing diagnostically important features that are comparable to the gold standard FFPE histology. As an assistive imaging platform, MUSI could facilitate the development of precise image-guided surgery and revolutionize the current practice in surgical pathology.

The ternary cathode material LiNi0.83Co0.12Mn0.05O2 (NCM) has excellent properties, such as superior energy density, low cost, and high voltage platform. Recently, it becomes one of the research hotspots of lithium-ion batteries (LIBs). However, NCM has insufficient cycle stability and cannot meet the demand for the high-rate capability, which limits its application in energy storage equipment. The precursor of NCM was modified with (Ni0.4Co0.2Mn0.4)1−xZrx(OH)2 by the co-precipitation. After high-temperature sintering, the diffusion of Zr4+ has significant impacts on the stability and capability for NCM. The doped sample exhibits a capacity retention rate of 79.5% at 1 C after 200 cycles and also delivers excellent rate performance, and the average specific discharge capacity is 189.4 mAh g−1 (2 C) and 180.6 mAh g−1 (5 C), respectively.

The layered lattice structure of the nickel-rich LiNi0.94Co0.04Al0.02O2 (NCA) cathode material has the advantages of high energy density and low cost. Unfortunately, high nickel materials’ application is limited due to the fast decay of capacity. Doping and coating are effective methods to enhance cycle stability. In this study, the effects of Ti doping on the electrochemical performances of NCA are systematically investigated. Ni0.94Co0.04Al0.02(OH)2 and TiO2 are directly mixed, and after sintering, Ti4+ ions diffused uniformly in the LiNi0.94Co0.04Al0.02O2 cathode particles. Besides, (Ni0.4Co0.2Mn0.4)0.78Ti0.22(OH)2 is coated onto the surface of Ni0.94Co0.04Al0.02(OH)2 precursor particles with a facile co-precipitation method, and after sintering, Ti4+ ions also diffused uniformly. The cathodes were cycled in the voltage range of 2.8–4.5 V at 1 C. As a result, the discharge capacity of Ni0.94Co0.04Al0.02(OH)2 changes from 201.4 to 119.8 mAh g−1, and the battery capacity decayed rapidly within 200 cycles. Although the initial discharge capacity of the doped and covered specimens was not significantly dissimilar from the original precursor specimens, the capacity has only dropped by 20% after 200 charges and discharges.

Codium fragile has attracted much attention due to its high economic and nutritional values. The light intensity and artificial aeration affect its growth and photosynthetic activity, which in turn affect its economic and nutritional values. The light intensities (30µmol·m− 2·s− 1, 60µmol·m− 2·s− 1, 90 µmol·m− 2·s− 1) and aeration regulation are investigated to the effect on the growth and photosynthetic physiology of C. fragile collected from the Bohai Sea, China. The results show that different light intensities have a highly significant effect on the maximal photochemical efficiency of PSII(Fv/Fm), photochemical quenching coefficient (qP), and a significant effect on the non-photochemical quenching coefficient (NPQ). They all decreased the least under 60µmol·m− 2·s− 1. The increase in the relative growth rate(RGR) of C. fragile during aeration was greater than that of the non-aeration group. At the same time, the Fv/Fm and qP decreased less than those of the non-aeration group. It shows that the aeration regulation had a highly significant effect on the wet weight, Fv/Fm and qP of C. fragile. Among the six groups, only aeration and light intensities of 60 and 90µmol·m− 2·s− 1 were suitable for the growth of C. fragile, because the Fv/Fm decreased less and the qP increased. The result shows that the interaction of the two environmental factors had a significant effect on the Fv/Fm and qP of C. fragile, while there was no significant effect on the wet weight and NPQ.

Optical-resolution photoacoustic microscopy (OR-PAM) has been widely used for imaging blood vessel and oxygen saturation of hemoglobin (sO2), providing high-resolution functional images of living animals in vivo. However, most of them require one or multiple bulky and costly pulsed lasers, hindering their applicability in preclinical and clinical settings. In this paper, we demonstrate a reflection-mode low-cost high-resolution OR-PAM system by using two cost-effective and compact laser diodes (LDs), achieving microvasculature and sO2 imaging with a high lateral resolution of ∼6 µm. The cost of the excitation sources has dramatically reduced by ∼20–40 times compared to that of the pulsed lasers used in state-of-the-art OR-PAM systems. A blood phantom study was performed to show a determination coefficient R2 of 0.96 in linear regression analysis. Experimental results of in vivo mouse ear imaging show that the proposed dual-wavelength LD-based PAM system can provide high-resolution functional images at a low cost.

The Ni-rich LiNi0.83Co0.12Mn0.05O2 (NCM83) cathode materials have drawn intensive attention due to the high energy density and low cost. However, Ni-rich LiNi1-x-yCoxMnyO2 still has the fatal weakness of poor cycle stability, limiting its further wide application. Bulk doping is an effective means to enhance the cycle stability, yet the electrochemical performances are very sensitive to the doping quantity. Here a facile method of co-precipitation is adopted to coat (Ni0.4Co0.2Mn0.4)1-xAlx(OH)2+x on precursor particles of NCM83. Al ions diffuse evenly in the NCM83 particles after sintering. The cells are operated at a high cut-off voltage of 4.5 V. The discharge capacity of NCM83 is 187.8 mAh g−1, and decays fast with cycles. The doped sample even exhibits a higher discharge capacity of 195 mAh g−1, and the capacity retention is improved to 83.8% after 200 cycles.

Ultraviolet photoacoustic microscopy (UV-PAM) has been investigated to provide label-free and registration-free volumetric histological images for whole organs, offering new insights into complex biological organs. However, because of the high UV absorption of lipids and pigments in tissue, UV-PAM suffers from low image contrast and shallow image depth, hindering its capability for revealing various microstructures in organs. To improve the UV-PAM imaging contrast and imaging depth, here we propose to implement a state-of-the-art optical clearing technique, CUBIC (clear, unobstructed brain/body imaging cocktails and computational analysis), to wash out the lipids and pigments from tissues. Our results show that the UV-PAM imaging contrast and quality can be significantly improved after tissue clearing. With the cleared tissue, multilayers of cell nuclei can also be extracted from time-resolved PA signals. Tissue clearing-enhanced UV-PAM can provide fine details for organ imaging.

Due to extensive morphological plasticity, the taxonomy of Cladophora species remains unclear. As one of the widely distributed species, C. gracilis was reported to hold many varieties, which make it difficult to identify the species. This study explored the morphology diversity of nine C. gracilis samples collected along the coast of western Yellow Sea. Some samples showed extremely varied characteristics, by which one cannot classify them correctly. Hence, 18S rDNA and nuclear ribosomal DNA internal transcribed spacer regions (ITS) sequences were employed to delimit species. For 18S rDNA, sequence similarity ranged from 99.6% to 100%. For ITS region, the similarity ranged from 98.7% to 100%. Molecular data strongly suggested that the morphologically heterogeneous samples were actually the same species. Characteristics comparison of the samples revealed that the taxonomy criteria including branching pattern and density, thallus color, height and texture varied widely, influenced by environmental conditions and age of alga. Besides, cell dimensions, as the relatively stable criterion, also exhibited intraspecific variance. Successful application of 18S rDNA and ITS sequences indicated that molecular method can be a powerful assistant as DNA barcodes to traditional morphology taxonomy.

Garnet structure electrolyte Li7La3Zr2O12 (LLZO) exhibits high ionic conductivity, high fracture toughness, and low strain during cycling. The mechanical stability of cathodes could be improved by an LLZO coating. Nevertheless, the electronic conductivity of LLZO is in the order of 10−9 S cm−1, and therefore the electron conduction of cathodes is blocked by the LLZO coating layer. The electronic conductivity is raised by doping variable valence elements (Fe, Co, Ni) into garnets. The doping has only a weak effect on the ionic conductivity, while the electronic conductivity is increased to 10−6 S cm−1. Co-doped sample exhibits the highest electronic conductivity of 2.75 × 10−6 S cm−1. The mixed conducting garnets could be used as the coating material of cathodes, and besides could reduce the interfacial resistance between cathodes and solid electrolyte in all-solid-state batteries.

Li-rich Mn-based layered oxide Li1.2Mn0.54Ni0.13Co0.13O2 (LMNCO) has received great interest due to its high discharge capacity. However, the fast capacity attenuation seriously hinders its wide application. LMNCO particles are synthesized via a co-precipitation method. To enhance the cycle stability, (Ni0.4Co0.2Mn0.4)1-xTix(OH)2+2x surface layer is deposited on LMNCO precursor particles by a second co-precipitation process. Due to the mutual diffusion of elements during sintering, Ti is distributed in the 2–3 μm shell of particles. The cells are cycled in a voltage window of 2.0–4.8 V at 0.5C. After 200 cycles, LMNCO exhibits a capacity retention of 43%, and LMNCO particles have been pulverized by the cycle process. In contrast, the structural integrity of coated particles is maintained, and therefore the cycle stability is evidently improved.

Based on specimens collected in Yinggehai, Hainan, China from 2013 to 2016, a stable epiphytic taxon is found on the surface of the individual of marine green alga Cladophora aokii Yamada. According to the morphological characteristics, the taxonomy of Cl. aokii and its epiphytes is carried out. There are some epiphytes attached on Cl. aokii Yamada including Cl. fascicularis (Mertens ex C. Agardh) Kutzing, Chaetomorpha pachynema (Montagne) Kutzing, Ceramium camouii Dawson, Licmophora abbreviata Agardh, Lyngbya sp. and Chattonella sp.. The formation of the individual of Cl. aokii is dissected and explained, which can help to analyze the adaption in details among this species, its epiphytes and native marine environment. The results reveal the marine macroepiphytic taxonomy in Hainan, China, and preliminarily explain the adaptive relationship between macroalgae and environment.

Solid oxide electrolytes with high Li ion conductivity and mechanical stability are vital for all solid-state lithium ion batteries. The perovskite material Li x La 0.557 TiO 3 with various initial Li (0.303 ≤ x ≤ 0.370) is synthesized by traditional solid-state reaction. The cubic and tetragonal structures are prepared with fast and slow cooling, respectively. The results reveal that the Li ion conductivity of the cubic structure is higher. In fact, the bulk conductivity of 1.65 × 10 −3 S cm −1 is obtained at room temperature for x = 0.350. The crystal structure is not affected by the Li 2 O quantity. In addition, Young's modulus, hardness, and fracture toughness are determined with indentation method for both structures. The Young's modulus increases with increasing Li 2 O. However, hardness and fracture toughness keep a relatively stable value independent of Li 2 O quantity.

LiNi0.83Co0.12Mn0.05O2 (NCM83) is considered as a potential cathode material owing to its high energy density and low cost, yet the discharge capacity decays rapidly with the cycles. Dual doping of Mg and Ti is used to improve electrochemical stability. MgxTixMn1-2x(OH)2+x is uniformly coated on the surface of precursor particles by co-precipitation method, and MgxTixMn1-2x diffuses evenly during the sintering process. Mg and Ti successfully enter into the crystal lattice of NCM83. The cells are cycled in 2.8–4.5 V at 1C for 200 cycles. The specific capacity of NCM83 is 192.1 mAh g−1, and the capacity retention is 61.8% after 200 cycles. The cyclability can be significantly enhanced by dual doping of Mg and Ti, which can maintain 84.3% capacity under the same condition.

The electrochemical performances of electrode materials in lithium secondary batteries are closely correlated with their mechanical integrity. Direct design of surface layer based on mechanical properties can significantly simplify the optimization process. The Young’s modulus (E), hardness (H) and fracture toughness (K IC ) of prototypical LiNi 0.8 Co 0.15 Al 0.05 O 2 (NCA) are characterized with indentation method. E and H decrease over by 50%, and K IC decreases by 38% with delithiation. By contrast, the mechanical properties of NCA are effectively stabilized by Ti-doping. NCA exhibits much higher strain with lithiation/delithiation compared to the solid solution, and is tend to fracture during charge-discharge. Therefore, NCA samples with a nanoscale Ti-doped surface layer are prepared, and the mechanical stability is significantly enhanced by the surface layer. After 100 cycles, all the pristine NCA particles have been pulverized by the lithiation/delithiation processes, while almost all the particles with Ti-doped surface layer are intact. Correspondingly, the cycle life of particles with Ti-doped surface layer is dramatically improved.

Solid electrolytes with high lithium ionic conductivity and outstanding mechanical stability are essential for all-solid-state lithium ion batteries. Perovskite LixLa0.5TiO3 is one of the most promising as solid electrolytes candidates. LixLa0.5TiO3 with various initial Li2O (0.5 ≤ x ≤ 0.569) is synthesized by traditional solid state reaction at high temperatures. The crystal structure is not remarkably affected by the Li2O quantity, yet higher porosity is obtained as a result of excess Li2O. The Young's modulus, hardness and fracture toughness are evaluated with indentation method. The Young's modulus increases from 72 GPa to 148 GPa with increasing Li2O, which means that a small variation of Li quantity in LixLa0.5TiO3 results in over a 100% change of Young's modulus. However, the fracture toughness exhibits an opposite trend with that of the Young's modulus. The high Young's modulus and fracture toughness could guarantee the structural integrity during cycle operations. This article is protected by copyright. All rights reserved

The wide applications of Ni-rich LiNi1- x-y Cox Mny O2 cathodes are severely limited by capacity fading and voltage fading during the cycling process resulting from the pulverization of particles, interfacial side reactions, and phase transformation. The canonical surface modification approach can improve the stability to a certain extent; however, it fails to resolve the key bottlenecks. The preparation of Li(Ni0.4 Co0.2 Mn0.4 )1- x Tix O2 on the surface of LiNi0.8 Co0.1 Mn0.1 O2 particles with a coprecipitation method is reported. After sintering, Ti diffuses into the interior and mainly distributes along surface and grain boundaries. A strong surface and grain boundary strengthening are simultaneously achieved. The pristine particles are fully pulverized into first particles due to mechanical instability and high strains, which results in serious capacity fading. In contrast, the strong surface and the grain boundary strengthening can maintain the structural integrity, and therefore significantly improve the cycle stability. A general and simple strategy for the design of high-performance Ni-rich LiNi1- x - y Cox Mny O2 cathode is provided and is applicable to surface modification and grain-boundary regulation of other advanced cathodes for batteries.

Sodium-ion batteries (SIBs) have great development potential in the field of grid energy storage thanks to the abundant sodium resources. The electrochemical performances of SIBs are mainly determined by cathode materials. Among them, P2-Na2/3Ni1/3Mn2/3O2 has high capacity and structural stability. The morphology and crystal structure are affected by Na sources, and the sample with Na2CO3 as Na source has better electrochemical performances. The electrochemical performances of P2-Na2/3Ni1/3Mn2/3O2 differ dramatically depending on the cut-off voltages. P2-Na2/3Ni1/3Mn2/3O2 exhibits an initial discharge capacity of 164.7 mAh g−1 in a voltage range of 2.0–4.3 V, while the capacity retention is only 27.6% after 100 cycles. The cycle stability can be significantly improved by Li and Mg doping, respectively. However, the initial discharge capacity is obviously reduced by doping. Na2/3Li0.1Ni0.23Mn0.67O2 and Na2/3Mg0.1Ni0.23Mn0.67O2 exhibit a capacity of 121.5 mAh g−1 and 114.6 mAh g−1, respectively. The capacity retention of Na2/3Mg0.1Ni0.23Mn0.67O2 reaches 89.7% after 100 cycles.