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In this study, Ni/W–TiN composites were fabricated by the pulse current electrodeposition (PCE) method. The effects of TiN concentration on the microstructure, microhardness, and wear properties of the resulting composites were investigated by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), microhardness tester, and friction wear testing. Among the four obtained composites, Ni/W–TiN composite prepared at 8 g/L showed the densest and finest surface structure. The TiN contents in obtained Ni/W–TiN composites at 8 and 16 g/L were estimated to 8.1 and 5.4 wt%, respectively. The average Ni/W grain diameter in Ni/W–TiN composite obtained at 8 g/L TiN was recorded as 84.7 nm. The protrusion and depression heights of the composite deposited at 8 g/L were 81.8 and 45.4 nm, respectively. This composite also processed an average microhardness of 897.6 HV, with only a few shallow and narrow scratches on its worn surface, demonstrating its prominent wear resistance when compared to the other three composites.

Sodium-ion batteries (SIBs), being an attractive candidate of lithium-ion batteries, have attracted widespread attention as a result of sufficient sodium resource with low price and their comparable suitability in the field of energy storage. However, one of the main challenges for their wide-scale application is to develop suitable anode materials with excellent electrochemical performance. Herein, a novel orderly layered VMoS2 (OL-VMS) anode material was synthesized through a facile hydrothermal self-assembly approach followed by a heating procedure. As the anode material of the SIBs, the unique structure of OL-VMS not only facilitated the rapid migration of sodium ions between the stacked layers but also provided a stable framework for the volume change in the process of intercalation/deintercalation. In addition, vanadium mediating in the framework caused more defects to produce abundant storage sites for Na+. As such, the obtained OL-VMS-based anode exhibited high reversible capacities of 602.9 mAh g-1 at 0.2 mA g-1 and 534 mAh g-1 even after 190-cycle operation at 2 A g-1. Furthermore, the OL-VMS-based anode delivered an outstanding specific capacity of 626.4 mAh g-1 after 100-cycle testing at 2 A g-1 in a voltage range from 0.01 to 3 V. In particular, even in the absence of conductive carbon, it still showed an excellent specific capacity of 260 mAh g-1 at 1 A g-1 after 130 cycles in a 0.3-3 V voltage range, which should contribute to the cost reduction and energy density increase.

Alligatorweed [Alternanthera philoxeroides (Mart.) Griseb.] is an invasive semiaquatic weed that poses a serious threat to agricultural production and ecological balance worldwide. However, information about genetic factors associated with the adaptation and invasion mechanisms of this species is limited. Screening for appropriate reference genes is important for gene expression and functional analysis research in A. philoxeroides. In this study, 30 candidate genes that showed stable expression in different A. philoxeroides tissues under various treatments in RNA-seq data were chosen to design quantitative real-time PCR (qRT-PCR) primers. After the amplification specificity validation, 25 candidates were selected and further evaluated in a diverse set of A. philoxeroides samples, including leaf, stem, and root tissues under drought, salinity, heat, chilling, five herbicides, and corresponding untreated controls using qRT-PCR. The delta-CT method, geNorm, NormFinder, BestKeeper, and RefFinder algorithms were used to identify stable reference genes from A. philoxeroides samples. Overall, CoA, RFI2, Tubby, SRP19, and V-ATPase were the top five ideal reference genes in all organs and conditions. Tubby and CoA were the most stable reference genes in the leaf/stem; and RFI2, ERprr, and SPR19 were suitable reference genes for the roots. This work provided a foundation for exploring gene expression profiling of A. philoxeroides, especially those adaptation- and invasion-related genes, which may help in management of this invasive weed.

In this study, Ni–SiC composite coatings with improved wear and corrosion resistance were obtained by ultrasonic electrodeposition (UED) method. The microstructure, microhardness, corrosion and abrasion resistance, and sectional composition distribution of the composite coatings were investigated by atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), electrochemical workstation, Vickers microhardness testing, and wear testing. AFM and HRTEM results revealed compact surface structure of Ni–SiC composite coating prepared by UED. Mean diameter of Ni crystals was 68.4 nm, whereas that of SiC nanoparticles present within the composite was 26.7 nm. According to XPS data, contents of Si in UED deposited Ni–SiC composite coating were approximately 23.7 at.%, whereas that of Ni was about 46.8 at.%. Ni–SiC composite coating deposited via UED method exhibited largest microhardness (715.7 HV) compared to other coatings, whereas nickel coating had mean microhardness of 485.8 HV. Icorr and Ecorr values of Ni–SiC composite coatings deposited via UED were 1.13 × 10−3 mA/cm2 and −0.311 V, respectively, indicating optimal level of corrosion resistance. Besides, surface morphological analysis of the coating revealed it to be glossy with only minor surface scratches, exhibiting the best wear resistance.

The plant immune system is fundamental for plant survival in natural ecosystems and for productivity in crop fields. Substantial evidence supports the prevailing notion that plants possess a two-tiered innate immune system, called pattern-triggered immunity (PTI) and effector-triggered immunity (ETI). PTI is triggered by microbial patterns via cell surface-localized pattern-recognition receptors (PRRs), whereas ETI is activated by pathogen effector proteins via predominantly intracellularly localized receptors called nucleotide-binding, leucine-rich repeat receptors (NLRs)1–4. PTI and ETI are initiated by distinct activation mechanisms and involve different early signalling cascades5,6. Here we show that Arabidopsis PRR and PRR co-receptor mutants—fls2 efr cerk1 and bak1 bkk1 cerk1 triple mutants—are markedly impaired in ETI responses when challenged with incompatible Pseudomonas syrinage bacteria. We further show that the production of reactive oxygen species by the NADPH oxidase RBOHD is a critical early signalling event connecting PRR- and NLR-mediated immunity, and that the receptor-like cytoplasmic kinase BIK1 is necessary for full activation of RBOHD, gene expression and bacterial resistance during ETI. Moreover, NLR signalling rapidly augments the transcript and/or protein levels of key PTI components. Our study supports a revised model in which potentiation of PTI is an indispensable component of ETI during bacterial infection. This revised model conceptually unites two major immune signalling cascades in plants and mechanistically explains some of the long-observed similarities in downstream defence outputs between PTI and ETI. Bacteria elicit two distinct immune responses in Arabidopsis thaliana, mediated by diverse signalling receptors but working in a synergistic manner.

Transcriptional regulatory protein (TRP)-based whole-cell biosensors are widely used nowadays. Here, they were demonstrated to have great potential application in screening cell efflux and influx pumps for small molecules. First, a vanillin whole-cell biosensor was developed by altering the specificity of a TRP, VanR, and strains with improved vanillin productions that were selected from a random genome mutagenesis library by using this biosensor as a high-throughput screening tool. A high intracellular vanillin concentration was found to accumulate due to the inactivation of the AcrA protein, indicating the involvement of this protein in vanillin efflux. Then, the application of this biosensor was extended to explore efflux and influx pumps, combined with directed genome evolution. Elevated intracellular vanillin levels resulting from efflux pump inactivation or influx pump overexpression could be rapidly detected by the whole-cell biosensor, markedly facilitating the identification of genome targets related to small-molecule transmembrane transport, which is of great importance in metabolic engineering.

Due to the temperature and concentration determine the kinetic undercooling of interface growth and nucleation undercooling inside the melt, they play an important role in the solidification microstructure of the alloy. In this paper, the effect of temperature gradient and cooling rate on the dynamic undercooling was studied and the mechanism of the concentration at the solid-liquid interface on the kinetic undercooling during the continuous cooling process was analyzed. A calculation method for the coupling of temperature and concentration during Inconel 718 alloy solidification was developed, which can solve the problem that the concentration and temperature are difficult to be calculated at the same time in the numerical calculation.

The electrochemical performance of the Ni0.8Co0.15Al0.05LiO2 (NCAL) cathode was investigated by comparing it with the traditional La0.4Sr0.6Co0.2Fe0.8O3-δ (LSCF) and LSCF/Ce0.9Gd0.1O2-δ (GDC) cathodes with a GDC electrolyte-supported solid oxide fuel cell (SOFC). It is found that the electrochemical performance of the cells with the NCAL and NCAL/GDC cathode is better than that of the cells with the LSCF and LSCF/GDC cathode at 550 °C. The results of the electrochemical performance tests of the cells with different NCAL/GDC mass ratios (10/0, 9/1, 8/2, 7/3 and 6/4) show that the NCAL/GDC composite cathode with the mass ratio of 8/2 has the best electrochemical performance. XRD results show that when the sintering temperature is higher than 700 °C, the NCAL/GDC composite will undergo chemical reactions and generate new phases, reducing the performance of the composite cathode. XPS results show that a small amount of Li2CO3 was formed on the surface of NCAL during cathode preparation, forming a special interface between NCAL, Li2CO3 and GDC. At the NCAL-Li2CO3/GDC interfaces, due to the migration and aggregation of Li+ to the interface, a space charge region may be formed in which the Li+ enrichment may lead to the formation of the region with a high oxygen vacancy concentration. A very high oxygen vacancy concentration at the NCAL-Li2CO3/GDC interfaces will provide sufficient oxygen ion conductivity for oxygen reduction reaction (ORR) and reduce the activation energy of the reaction. NCAL will be a potential cathode material that can reduce the operating temperature of the traditional SOFC to 550 °C or lower.

The effects of Li2CO3 and LiOH on the ionic conductivity of BaCe0.9Y0.1O3(BCY)-x%Li2CO3 (x = 0, 5, 10 and 30) and BCY-y%LiOH (y = 0, 2, 5 and 8) composite electrolytes were investigated. Symmetrical cells with the structure of foam Ni–Ni0.8Co0.15Al0.05LiO2 (NCAL)∖BCY-x%Li2CO3 or y%LiOH∖foam Ni-NCAL and Pt∖BCY-x%Li2CO3 or y%LiOH∖Pt were prepared with NCAL-coated foam Ni and porous Pt as symmetrical electrodes, respectively. The ionic conductivity test results of the cells with Pt as the symmetrical electrode showed that the addition of LiOH did not improve the ionic conductivity of the BCY electrolyte, while the addition of Li2CO3 could significantly improve the ionic conductivity of the BCY electrolyte. The maximum power density of the cells with the structure of foam Ni-NCAL∖BCY-x%Li2CO3 or y%LiOH∖foam Ni-NCAL decreases with the increase in the amount of Li2CO3 or LiOH, which indicates that adding Li2CO3 or LiOH to BCY via mechanical mixing did not improve the electrochemical performance of the cells with NCAL as the electrode, and the NCAL electrode has the greatest impact on the performance of the cells. The interface of Li2CO3 and BCY should be a high-speed channel for ion conduction. Increasing the effective area of the interface between BCY and Li2CO3 and optimizing its continuity in the electrolyte should be the main development direction for improving the ionic conductivity.

The hydrogen induced intergranular crack is most common in hydrogen embrittlement phenomenon. Hydrogen atoms will preferentially diffuse into grain boundaries and then accumulate in them. Therefore, it is necessary to reveal the diffusion mechanism of hydrogen atoms at grain boundaries, which is helpful for deeply understanding hydrogen embrittlement. In this work, we performed first-principles calculations to investigate the trapping sites and diffusion behaviours of hydrogen atoms at Σ3 [ 1 ¯ 10] (111), Σ5 [ 1 ¯ 00] (021) and Σ9 [110] (2 2 ¯ 1) grain boundary structures of γ-Fe. Hydrogen atoms have no tendency to be segregated from the bulk to the Σ3 GB but hydrogen atoms tend to segregate into the Σ5 and Σ9 GBs. The solution energy of hydrogen in grain boundaries is mainly the consequence of the chemical bonding between Fe atoms in GBs and the hydrogen atom. In addition, according to the hydrogen diffusion behaviour in grain boundaries, Σ3 and Σ5 GBs act as three-dimensional barriers for hydrogen migration while the Σ9 GB acts as a one-dimensional barrier for H diffusion. Significantly, the difficulty of hydrogen diffusion along grain boundary mainly depends on the connectivity of low electron density region along grain boundary. This conclusion can provide a deep understanding of hydrogen distributions at different grain boundaries in metal materials, which is helpful for hydrogen embrittlement resistant materials design on the basis of grain boundary regulation.

The north-south transitional zone in China mainly consists of the Qinling-Daba Mountains. It is the most important West-East geo-ecological space in China, containing protected areas vital for biodiversity conservation and ecological security of China. The protection and rational development of its natural habitat is of great significance to China’s ecological security and integration of protected areas based on mountain forest ecosystems on a global scale. In this study, five important types of protected areas in the transitional zone were selected, and their spatial patterns were analysed. Spatial analysis methods, such as kernel density estimation and accessibility analysis, were employed for both point and areal data, and focused on four aspects: land use scale, shift in the centre of gravity, spatial agglomeration, and accessibility. In addition, policy background and evolution of spatial and temporal characteristics of the protected area system in the transitional zone from 1963 to 2017 were also examined. We analysed the characteristics and geographical significance of the West-east corridor using the spatial pattern of the protected area system from the perspective of ecological and economic spaces. We focused on spatial shape, type intersection, and key areas to analyse the spatial overlap of the protected areas. Protected area establishment was divided into three stages: initial (1956–1980), rapid development (1981–2013), and national park transformation (2014–present). These stages reflected the change in the concept of ‘simple protection—sustainable use—integration and upgrade’ for protected areas of China. The spatial centre of gravity of the protection zone system was located in the west Qinling-Daba Mountains, and its high-density core exhibited a relatively stable N-shaped structure composed of four gathering areas. Affected by factors such as geographic environment and socio-economic development density, the average access time for protected areas was high (1.56 h); wetland parks and scenic areas are located closer to the city centre. As the West-east corridor in the transitional zone extends from west to east, there is a clear spatial dislocation between the development of protected areas and the intensity of human activities. During development, differentiated goal orientation should be adopted based on the idea of zoning and classified governance. With the advancement of the construction of protected areas, the spatial overlap of protected areas in the transition zone has become more prominent. At present, the spatially overlapped protected areas in the transitional zone remain prominent, with inclusion overlap being the most common, and forest parks exhibiting the highest probability of overlap with other protected areas, we should focus on in the integration process of the corridor-type ecological space based on the mountain forest ecosystem.

Ni-SiC composite coatings with good wear and corrosion resistance could be obtained by the ultrasonic electrodeposition (UED) method in this study. The microstructure, microhardness, corrosion and abrasion resistance, and sectional composition distribution of the composite coatings were investigated employing atomic force microscopy (AFM), scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS), electrochemical workstation, Vickers microhardness testing, and wear testing. In addition, the statistical distributions of Ni grains in Ni coating and Ni-SiC composites were counted by using a “Nano Measurer” software. The outcome of AFM and HRTEM revealed a compact surface structure of Ni-SiC composite coating made by the UED. The mean diameter of Ni crystals was 68.4 nm, whereas that of SiC nanoparticles present within the composite was 26.7 nm. According to the XPS data, the content of Si in the Ni-SiC composite coating prepared via UED was approximately 23.7 at.% whereas that of Ni was about 46.8 at.%. The Ni-SiC composite coating deposited via UED method was found to have the largest value for microhardness (715.7 HV) compared to other coatings, although the nickel coating had a mean microhardness of 485.8 HV only. The Icorr and Ecorr values of the Ni-SiC composite coating deposited via UED were 1.13 × 10−3 mA/cm2 and − 0.311 V, respectively, indicating an optimal level corrosion resistance. Besides, the surface morphological analysis of the coating revealed that it was glossy with only minor surface scratches, and it exhibited the best resistance to wear.

Density functional theory (DFT) calculations are used to explore the adsorption characteristics and degradation mechanism of sulfacetamide on anatase TiO2(101) and (001) surfaces. The most probable adsorption configuration was firstly determined by comparing the adsorption energies and structural bond lengths before and after adsorption. After adsorption, some of the bond lengths are elongated. We have proposed about six possible degradation pathways of sulfacetamide, such as branch chain breaking, benzene ring dihydroxylation, amino substitution and sulphur nitrogen bond breaking. And the relevant degradation processes are studied in detail. Based on the calculated results, we conclude that the TiO2(001) surface is more suitable for the degradation of sulfacetamide considering its much smaller energy barriers in several degradation paths than the TiO2(101). Among all the six possible degradation paths, we find that the hydroxyl radical attacks of C(1), C(3) and N(6) atoms of the (001) surface and the C(4) atom of (101) surface sulfacetamide are most probable reaction pathways due to their much smaller energy barriers, i.e. 7.7, 26.1 kcal mol−1 and 14.6, 23.4 kcal mol−1 indicating that these reactions can easily take place in room temperature. Our computational results are not only consistent with the experimental results of sulfacetamide degradation, but also reveal the possible microscopic mechanisms of the photocatalytic reaction.

Designing antibody-powered DNA nanodevice switches is crucial and fascinating to perform a variety of functions in response to specific antibodies as regulatory inputs, achieving highly sensitive detection by integration with simple amplified methods. In this work, we report a unique DNA-based conformational switch, powered by a targeted anti-digoxin mouse monoclonal antibody (anti-Dig) as a model, to rationally initiate the hybridization chain reaction (HCR) for enzyme-free signal amplification. As a proof-of-concept, both a fluorophore Cy3-labeled reporter hairpin (RH) in the 3' terminus and a single-stranded helper DNA (HS) were individually hybridized with a recognition single-stranded DNA (RS) modified with Dig hapten, while the unpaired loop of RH was hybridized with the exposed 3'-toehold of HS, isothermally self-assembling an intermediate metastable DNA structure. The introduction of target anti-Dig drove the concurrent conjugation with two tethered Dig haptens, powering the directional switch of this DNA structure into a stable conformation. In this case, the unlocked 3'-stem of RH was implemented to unfold the 5'-stem of the BHQ-2-labeled quench hairpin (QH), rationally initiating the HCR between them by the overlapping complementary hybridization. As a result, numerous pairs of Cy3 and BHQ-2 in the formed long double helix were located in spatial proximity. In response to this, the significant quenching of the fluorescence intensity of Cy3 by BHQ-2 was dependent on the variable concentration of anti-Dig, achieving a highly sensitive quantification down to the picomolar level based on a simplified protocol integrated with enzyme-free amplification.

The combination of microstructures and nanostructures has broad application prospects. However, most existing methods are oriented to fabricating microstructures and nanostructures separately, and the fabrication of nanostructures on a microstructured surface at the wafer level is rarely studied. In this work, a new method of fabricating large-area high aspect ratio nano-cylinders on micro-pillars based on a colloidal crystal mask is proposed. An experimental device for stripping and draining was designed to create a polystyrene colloidal crystal mask. Together with reactive-ion etching and metal-assisted chemical etching, high aspect ratio nano-cylinders on micro-pillars with controllable size were obtained on a 4-inch silicon wafer. Wetting tests were performed on four groups of fabricated structures of different sizes, and the results showed that all samples were superhydrophobic. Thus, a method for fabricating uniform, size-controllable, large-area high aspect ratio nano-cylinders on micro-pillars with great potential as a superhydrophobic engineering material is proposed.

Pattern-triggered immunity and effector-triggered immunity are two primary forms of innate immunity in land plants. The molecular components and connecting nodes of pattern-triggered immunity and effector-triggered immunity are not fully understood. Here, we report that the Arabidopsis calcium-dependent protein kinase CPK3 is a key regulator of both pattern-triggered immunity and effector-triggered immunity. In vitro and in vivo phosphorylation assays, coupled with genetic and cell biology-based analyses, show that actin-depolymerization factor 4 (ADF4) is a physiological substrate of CPK3, and that phosphorylation of ADF4 by CPK3 governs actin cytoskeletal organization associated with pattern-triggered immunity. CPK3 regulates stomatal closure induced by flg22 and is required for resistance to Pst DC3000. Our data further demonstrates that CPK3 is required for resistance to Pst DC3000 carrying the effector AvrPphB. These results suggest that CPK3 is a missing link between cytoskeleton organization, pattern-triggered immunity and effector-triggered immunity., Remodelling of the actin cytoskeleton occurs during plant immune responses to pathogens. Here Lu et al. show that this process requires the calcium-dependent kinase CPK3 which phosphorylates actin depolymerizing factor 4 and is required for both PAMP and effector-triggered immunity in Arabidopsis.

The finite control set (FCS) model predictive current control (MPCC) is a promising control scheme for the five-phase drives due to the easy-tuning process. However, the deteriorated operational performance and huge computational burden are the real challenges. This article proposes a multivector FCS-MPCC, which can improve the operational performances without increasing computational burden. In the proposed method, the candidate virtual voltage vectors with harmonics-free are employed as the basic control set. Then, each sector is partitioned to generate more available vectors. The duty-cycle modulation technology is used to optimize the amplitude of the candidate vector. Therefore, a better control effect can be obtained. Also, a sector judgment method is proposed to determine the optimal control set, which can reduce the computational burden. By using this method, the optimal vector can be selected accurately without evaluating all the available vectors. Thus, the computational burden can be alleviated. The experimental results are presented to confirm the effectiveness of the proposed multivector FCS-MPCC method.

Plant-derived polyphenol coating offers a promising route to fabricate functional surfaces for different substrate materials. However, almost all of the deposition approaches are time-consuming and involve inefficient processes, and the mechanisms behind the coating deposition are rarely understood. Herein, we report a rational methodology to achieve the rapid deposition of poly(caffeic acid) (PCA) by using H2O2 as a trigger under the assistance of copper sulfate (CuSO4). The comparative monomer structure of PCA oxidation polymerization has illustrated a significant distinction in the reaction path for PCA coating deposition which has never been reported before. Until now, the unprecedented fast velocity for polyphenol coating has been obtained, and the PCA coating exhibits excellent homogeneity, spatiotemporal tunability, and firm stability. Moreover, three different types of filtration membranes, poly(vinylidene fluoride) microfiltration membrane (PVDF MF membrane), poly(ether sulfone) (PES) ultrafiltration (UF) hollow fiber membrane, and PCA-coated PES nanofiltration (NF) membrane, are all successfully dip-coated using H2O2-triggered PCA coating. Without synthetic complexities and intricate procedures, the formation of hydrophilic and homogeneous PCA aggregates on the surface and/or inside pore walls resulted in various membranes. The as-prepared PCA-coated PVDF MF membrane demonstrates excellent oil/water separation efficiency of less than 150 ppm and a flux recovery rate of approximately 90% even after five cycles. By one-step co-deposition of PCA and poly(2-ethyl-2-oxazoline) (PEtOx) on the PES UF membrane surface, hydrophilicity and biofouling resistance are implemented for efficient protein filtration. The PES NF membrane formed by the PCA layer exhibits high mono-/divalent ion selectivity and excellent chlorine resistance. Overall, these results represent a rapid and sustainable approach to tailor PCA coatings for versatile liquid separation processes.

Silk fibroin (SF) and polyhydroxyalkanoate (PHA) have received increasing attention in recent years because of their unique biodegradability and biocompatibility. Studies on SF or PHA-based materials that are intended for use as biomaterials have attracted great attention, but few studies have been conducted on SF/PHA composite materials. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) copolymers with varying ratios of the 3-hydroxyvalerate (HV) component are the most widely used member of PHAs. In this study, SF/PHBV composite nanofibers were prepared by electrospinning. The stability of the mixed solution of SF/PHBV was explored first. Fourier transform infrared (FTIR) spectroscopy was used to study the composition of the precipitates caused by mixing the SF solution with the PHBV solution. The morphology of the electrospun SF/PHBV composite nanofibers was observed by scanning electron microscopy (SEM). The average diameters of the pure PHBV, pure SF, SF/PHBV (the content ratio of solute SF/PHBV (w/w) was 10/1), and SF/PHBV (the content ratio of solute SF/PHBV (w/w) was 4/1) nanofibers were 495.12 ± 82.27, 67.88 ± 14.52, 171.10 ± 40.38, and 149.70 ± 28.57 nm, respectively. To discuss the influence of the electrospinning parameters on the spinning stability and morphology of the electrospun SF/PHBV (10/1) composite nanofibers, a univariate analysis experiment was designed. When the applied voltage was 15 kV, the feeding rate was 0.3 mL/h, and the tip-to-collector distance was 13 cm, the spinning stability, uniformity and formability of the SF/PHBV (10/1) composite nanofibers were excellent. In addition to FTIR analysis, X-ray diffraction (XRD) was also used to explore the structure of the electrospun SF/PHBV composite nanofibers. As the content of PHBV increased, the crystallinity of the SF/PHBV composite nanofibers could be improved. The thermogravimetric analysis (TGA) results indicated that the thermal stability of SF was better than that of PHBV. As the content of PHBV increased, the thermal stability of the SF/PHBV composite nanofibers would decrease.

Anthocyanins have good physiological functions, but they are unstable. The interaction between anthocyanins and proteins can improve the stability, nutritional and functional properties of the complex. This paper reviews the structural changes of complex of anthocyanins interacting with proteins from different sources. By circular dichroism (CD) spectroscopy, it was found that the contents of α-helix (from 15.90%−42.40% to 17.60%−52.80%) or β-sheet (from 29.00%−50.00% to 29.40%−57.00%) of the anthocyanins–proteins complex increased. Fourier transform infrared spectroscopy showed that the regions of amide I (from 1627.87−1641.41 cm−1 to 1643.34−1651.02 cm−1) and amide II (from 1537.00−1540.25 cm−1 to 1539.00−1543.75 cm−1) of anthocyanins–proteins complex were shifted. Fluorescence spectroscopy showed that the fluorescence intensity of the complex decreased from 150−5100 to 40−3900 a.u. The thermodynamic analysis showed that there were hydrophobic interactions, electrostatic and hydrogen bonding interactions between anthocyanins and proteins. The kinetic analysis showed that the half-life and activation energy of the complex increased. The stability, antioxidant, digestion, absorption, and emulsification of the complex were improved. This provides a reference for the study and application of anthocyanins and proteins interactions.

Yttria-modified silicide (MoSi2-Y2O3) oxidation-resistant coatings with multiple Y2O3 contents were prepared using supersonic atmospheric plasma spraying, and the oxidation resistance was investigated at 1700 °C with static atmosphere. Experimental results indicated that the sprayed MoSi2-Y2O3 coating possessed good compactness, which adhered well to the SiC transition layer. Meanwhile, the Y2O3 addition greatly enhanced the bonding strength of the coating, and extended its service life at 1700 °C. Wherein the MoSi2-20 wt.%Y2O3 coating exhibited the highest adhesive strength and best oxidation resistance with the lowest mass loss among all the coatings. In practice, the Y2O3 changed the microstructures of formed oxide glass scale during oxidation, and then modified the oxidation resistance of the coating. The action mechanism of Y2O3 on the oxidation behavior of MoSi2-Y2O3 coating was analyzed.

The cycling performance of batteries is largely determined by the electrode-electrolyte interphase associated with the chemical and electrochemical properties of electrolyte salts and solvents. In ...

Over the past few decades, seeding strategies for solution crystallization processes have been developed for various applications, and significant improvements in crystal quality and process robust...

Dark or weak-emissive DNA-harbored silver nanoclusters (AgNCs) can be remarkably lighted up when approaching to guanine bases. The resultant bright AgNCs acting as a fluorescent reporter are fascinating in biosensing. To explore the applicable guanine-enhanced emission of AgNCs for biosensing microRNA-155 (miR-155) as a model, here we designed a unique stem-loop hairpin beacon (HB) encoding with an miR-155-recognizable sequence and a AgNCs-nucleable template, as well as a hairpin helper tethering a partially locked guanine-rich (15-nt) tail (G15H), while two identical cytosine-rich segments were inserted in HB and G15H to merge for folding/unfolding of i-motif at changed pHs. Initially, the intact clusters populated in HB (HB/AgNCs) were almost nonfluorescent in a buffer (pH 7.0). Then, miR-155 was introduced to trigger a repeated hairpin assembly of HB and G15H by competitive strand displacement reactions at decreased pH 5.0 within 10 min, consequently generating numerous duplex DNA constructs (DDCs). With the resultant template of pH-responsive i-motifs incorporated in DDCs, their folding at pH 5.0 brought the proximity of unlocked G15 overhang to the clusters in a crowded environment, remarkably lighting up the red-emitting fluorescence of HB/AgNCs (λem = 628 ± 5 nm) for amplified signal readout. About 3.5-fold enhancement of quantum yield was achievable using different variants of i-motif length and G15 position. Simply by adding OH-, the configuration fluctuation of i-motifs was implemented for switchable fluorescence biosensing to variable miR-155. Based on a one-step amplification and signaling scheme, this subtle strategy was rapid, low-cost, and specific for miR-155 with high sensitivity down to 67 pM.

This study proposed a novel electroconductive carbon fiber/circulating fluidized bed fly ash based-geopolymer (CF/CFBFAG) composite, which possessed adjustable electrical conductivity and showed a ...

A solid oxide fuel cell with 1.2 mm thick nanocrystalline BCY (BaCe0.9Y0.1O3) electrolyte was prepared by the copressing method, and its electrochemical performance was tested in H2/air conditions. The maximum power density of the nanocrystalline electrolyte cell prepared with BCY powders calcined at 1000 °C and operated at 550 °C in H2 is 405.2 mW cm−2. The carriers of nanocrystalline BCY electrolyte were studied by using double-layer electrolyte cells with pure oxygen ion conductor GDC (Gd0.1Ce0.9O2) and proton conductor SCY (SrCe0.95Y0.05O3), sintered at high temperatures as proton and oxygen ion filters. It is found that nanocrystalline BCY is a mixed conductor of oxygen ions and protons. The results of hydrogen and oxygen concentration cells show that the transference number of oxygen ions in the nanocrystalline BCY prepared in this study is higher than that of protons. XPS and HRTEM results of BCY particles before and after performance testing showed that an amorphous layer containing a high concentration of oxygen vacancies and suspected carbonate was formed on the surface of BCY particles after fuel cell performance testing. We believe that the amorphous layer should be a high-speed ion conduction channel for nanocrystalline BCY electrolyte during performance testing.

To develop a new way of renewable utilization of ground granular blast furnace slag (GGBFS), a novel ZnO-loaded graphene-reinforced alkali-activated slag-based geopolymer (ZnO/GASG) nanocomposite was originally prepared. The photocatalytic performance of ZnO/GASG was evaluated by solar hydrogen production and wastewater treatment of dyeing pollutant. The mechanical strength results indicated that the lamellate graphene inserted in the substrate of alkali-activated slag-based geopolymer (ASG) has played a critical role in crack-arresting extension so as to lead the significant increases of compressive and flexural strengthens of GASG test block. The XRD, FESEM and XPS results revealed that ZnO in the form of amorphous state dispersed on the surface of GASG when the loading approached to 2 wt%, and ZnO existed in the form of zincite when the loading was greater than 10 wt%. UV–vis diffuse reflectance spectra demonstrated that the absorption edge all of ZnO/GASG nanocomposites were blue-shifted due to the quantum size effect. The highest photocatalytic activities for H2 production (2281.3 μmol/g) and wastewater degradation (95.7%, solar light) over 15ZnO/GASG composite were ascribed to the efficient separation of photoinduced electron-hole pairs. The hole and hydroxyl radical play significant role in photocatalytic degradation of dyeing pollutant.

Solid wastes exhibit excellent prospects in the removal of heavy metals from contaminated water. However, raw solid waste materials usually show mediocre uptake efficiency, it is imperative to func...

Continuous cooling transformation (CCT) diagrams of undeformed and 40% compressively deformed pearlite heat-resistant steels at 950°C were obtained by a combined method of dilatometry and metallogr...

Using lithium compounds as anode in ceramic fuel cells will form LiOH/Li2CO3 at the anode, which diffuse into the Gd-doped CeO2 (GDC) electrolyte significantly improving its ionic conductivity. Here the importance of the density and microstructure of the electrolyte on this conductivity improvement is analyzed. Test cells with Ni0.8Co0.15Al0.05LiO2 (NCAL) electrode and GDC electrolyte are prepared at four sintering temperatures of 900, 1100, 1300, and 1550 °C. The amount of LiOH/Li2CO3 that enters into the electrolyte from the NCAL anode decreases with increasing sintering temperature, which led to lower electrolyte ionic conductivity and fuel cell performance. The results of XPS and EPR show that the concentration of oxygen vacancy in GDC containing LiOH/Li2CO3 increased significantly. The effective interface of LiOH/Li2CO3-GDC composite electrolyte results in higher ionic conductivity as compared to the composite electrolytes with larger grains and a smaller amount of LiOH/Li2CO3 due to higher sintering temperatures.

In this study, we present the use of compositionally and structurally well-defined, oxide-supported nanoparticle Ni + Ga intermetallic compound (IMC) catalysts in the wet reforming of propane. The ...

Microwave-assisted hydrothermal reaction of 2-fluoro-3,5,6-tri(1H-1,2,4-triazol-1-yl)-1,4-benzenedicarbonitrile (L1) with silver(I) nitrate yields a coordination polymer [Ag3(L2)2(NO3)] n (1), in which the L2 ligand (HL2 = 2-hydroxy-3,5,6-tri(1H-1,2,4-triazol-1-yl)terephthalonitrile) is obtained by in situ ligand transformation from the L1 precursor. HL2 monohydrate has also been isolated by the microwave-mediated hydrolysis of L1 and structurally characterized. Single-crystal X-ray diffraction reveals that HL2 monohydrate comprises a zwitterionic HL2 moiety, while complex 1 displays an infinite L2-bridged double-chain structure. Given that the HL2 molecule has a large conjugated π system, complex 1 exhibits strong blue luminescence in the solid state at room temperature.

Physicochemical properties of arsenic sulfide sludge (ASS) from copper smelter (ASS-I) and lead−zinc smelter (ASS-II) were examined by XRD, Raman spectroscopy, SEM−EDS, TG−DTA, XPS and chemical phase analysis method. The toxicity characteristic leaching procedure (TCLP), Chinese standard leaching tests (CSLT), three-stage sequential extraction procedure (BCR) and batch leaching experiments (BLE) were used to investigate the environmental stability. The ASSs from different smelters had obviously different physicochemical and environmental properties. The phase composition and micrograph analysis indicate that ASS-I mainly consists of super refined flocculent particles including amorphous arsenic sulfide adhered with amorphous sulfur and that ASS-II mainly consists of amorphous arsenic sulfide. The valence state of arsenic in both sludges is trivalent, but the valence composition of sulfur is quite different. The ASSs have thermal instability properties. The results of TCLP and CSLT indicate that the concentrations of As and Pd in the leaching solution exceed the standard limits. More than 5% and 90% of arsenic are in the form of acid soluble and oxidizable fractions, respectively, which explains the high arsenic leaching toxicity and environmental activity of ASS. This research provides comprehensive information for the disposal of ASS from copper and lead−zinc smelter.

Herein, a facile intramolecular cyclization of 2-arylamino phenyl ketones is established to supersede the traditional high-temperature, strongly acidic conditions and achieve 9-substituted acridines, by virtue of the combination of 2,2,2-trifluoroethanol and tert-butyl bromide. This protocol can be merged well with the preceding Cu-catalyzed intermolecular Chan-Evans-Lam cross-coupling reactions, therefore enabling pot-economic modular synthesis of 9-substituted acridines from readily available 2-amino phenyl ketones and aryl boronic acids at room temperature.

The skin secretions of amphibians are a rich source of bioactive peptides. We isolated chensirin-1 and chensirin-2 from the skin secretion of the Chinese frog Rana chensinensis. Sephadex-G-50 and RP-HPLC were employed to purify these peptides. The amino acid sequences of these peptides were VLPLVGNLLNDLLGE and IIPLPLGYFAKKT, respectively, as determined by Edman degradation. The molecular weights were 1578.7 and 1460.8 Da, respectively, as analyzed by HPLC-ESI-MS. The chensirin cDNA was cloned by 5′ and 3′ amplification of cDNA ends, synthesized and purified. The antibacterial activities of the chensirins were tested using minimum inhibitory concentration, the results indicated that chensirins inhibit the growth of gram-negative and gram-positive bacteria. Among them, chensirin-1 is a novel peptide with a higher antibacterial activity compared to other similar antimicrobial peptides. These low molecular weight peptides with good antimicrobial efficacy are considered potential sources for developing new antimicrobial agents to improve traditional drug resistance.

The storage root of alligatorweed [Alternanthera philoxeroides(Mart.) Griseb.] growing in terrestrial habitats is an important metamorphic organ for its propagation, overwintering, and spread. However, the regulatory mechanism adventitious root expansion to form storage roots is still unclear. To reveal the changes accompanying the root-swelling process, we quantified sugar, soluble protein, and phytohormone content in adventitious and storage roots. Results demonstrated that sucrose, fructose, and soluble protein increased in storage roots, whereas abscisic acid (ABA), indoleacetic acid (IAA), brassinosteroid (BR), gibberellin, jasmonic acid, and cytokinin (trans-zeatin [tZ] and isopentenyladenine [iP] and the corresponding ribosidestZR and iPR).tZ-type (tZR andtZ) content decreased, suggesting the involvement of sugars and hormones in the formation of storage roots. To further reveal the molecular basis ofA.philoxeroides’s ability to form storage roots and provide candidate genes for molecular function analyses, we assembled a de novo transcriptome ofA.philoxeroidesbased on four sets of RNA-sequencing data. According to functional annotation and expression profiling, 42 unigenes involved in sucrose synthesis and hydrolysis were identified, in addition to 70, 58, and 78 unigenes in ABA, BR, and IAA signal transduction, respectively. The quantitative reverse transcriptase polymerase chain reaction analysis revealed 21 unigenes involved in sugar metabolism and hormone signal transduction were differentially expressed during the formation of storage roots. These results revealed metabolic changes during the formation of storage roots and provide candidate genes involved in sugar and phytohormone metabolism inA. philoxeroides.

Based on the density functional theory (DFT), the distribution of Al and Bronsted acid sites in zeolite ECR-1 were studied by utilization of SIESTA (Spanish Initiative for Electronic Simulations wi...

A series of compression tests were conducted at various temperatures and strain rates to experimentally investigate the hot-deformation characteristics and dynamic softening of an as-cast FeCrAl alloy. There is no evident decline in stress after the peak point of a flow curve despite the occurrence of dynamic recrystallization (DRX). This phenomenon pointed out that the occurrence of DRX in the alloy could not be identified depending only on flow curves. The constitutive equation for peak stress was constructed following the determination of hot-working parameters. The predicted results correlated well with the experimental data. The dynamic softening behavior was classified depending on the analysis of microstructure evolutions at different temperatures. The softening process was dominated by dynamic recovery (DRV) at 850 and 950 °C. The higher temperature could elevate the level of dynamic softening. The softening mechanisms at 1050 °C included DRV and continuous dynamic recrystallization (CDRX) characterized by the rotation of sub-grains from low-angle boundaries to high-angle boundaries. The rotation of sub-grains during the CDRX process was unlikely to affect the strong intensity of texture after the hot-deformation process.

Coal seam water injection is a widely used dust reduction technology in Chinese coal mines. During the process of coal seam water injection, a large amount of broken coal particles will accumulate in the pore, which will affect the flow characteristics of water. It's very important for improving the on-site coal seam water injection and dust reduction technology to study the influence of coal particles on the water migration law. In this paper, a spontaneous upward imbibition experiment was used to study the effect of coal particles stacked in front fractures on water migration in coal seam water infusion. Then, a mathematical model was established to express imbibition speed and stable imbibition height. The results show when the largest particle size is selected, theoretical calculation results of stable imbibition height is closest to the experimental data; coal particles with a size of 564–1589 μm have the greatest influence on the wetting phase of coal seam water infusion; the metamorphic grade and particle size of the samples mainly affect the initial stage of water migration, and the initial imbibition speed of each coal sample is quite different. However, with increasing imbibition height, the imbibition speed difference of each coal sample gradually decreases.

Twinning is commonly activated in plastic deformation of low stacking-fault face-centered cubic (Fcc) metals but rarely found in body-centered cubic (Bcc) metals under room temperature and slow strain rates. Here, by conducting in situ transmission electron microscopy (TEM) at atomic scale, we discover that, in stark contrast to those in most Fcc metals, a majority of deformation twins in Bcc metals are unstable and undergo spontaneously detwinning upon unloading. Such unexpected instability of Bcc twins is found to be closely related to the prevalence of the inclined twin boundaries—a peculiar structure where twin boundaries are not parallel to the twinning plane, and the degree of instability is in direct proportion to the fraction of the inclined twin boundary. This work provides significant insights into the structure and stability of deformation twins in Bcc metals., Body-centred cubic metals rarely show twinning during deformation. Here, the authors use high resolution transmission electron microscopy to show tungsten, a body-centred cubic metal, spontaneously undergoes detwinning when unloaded.

Rare earths with unique electronic structure and properties have incomparable advantages for modifying the comprehensive performance of silicide materials. In this study, MoSi2-based composite coatings with different rare-earth Yb2O3 contents were prepared using supersonic atmospheric plasma spraying, and their microstructural features and oxidation behavior at 1700 °C were investigated systematically. Results showed that the sprayed MoSi2-Yb2O3 composite coating possessed the dense structure without visible defects and tightly adhered to the SiC transition layer. During oxidation at 1700 °C, all the samples exhibited an explicit linear oxidation mode, in which the MoSi2-10 wt%Yb2O3 coating qualified the optimal oxidation resistance with the lowest specific mass loss relative to other coatings. It was natural to consider that the Yb2O3 dopant changed the microstructural aspects of the formed oxide scale upon oxidation, and then affecting the oxidation behavior of the applied coating. Moderate doping of Yb2O3 stabilized the Si–O covalent bonds in SiO2 network, leading to the enhanced viscosity of oxide glass scale, thereby delaying the effective delivery of oxygen molecules as well as the oxidation degradation of the coating.

The phase transformation and microstructure evolution of pearlite heat-resistant steel during heating were observed with an ultra-high temperature confocal scanning laser microscope. The α-ferrite ...

The aboveground parts of terrestrial plants, collectively called the phyllosphere, have a key role in the global balance of atmospheric carbon dioxide and oxygen. The phyllosphere represents one of the most abundant habitats for microbiota colonization. Whether and how plants control phyllosphere microbiota to ensure plant health is not well understood. Here we show that the Arabidopsis quadruple mutant (min7 fls2 efr cerk1; hereafter, mfec)1, simultaneously defective in pattern-triggered immunity and the MIN7 vesicle-trafficking pathway, or a constitutively activated cell death1 (cad1) mutant, carrying a S205F mutation in a membrane-attack-complex/perforin (MACPF)-domain protein, harbour altered endophytic phyllosphere microbiota and display leaf-tissue damage associated with dysbiosis. The Shannon diversity index and the relative abundance of Firmicutes were markedly reduced, whereas Proteobacteria were enriched in the mfec and cad1S205F mutants, bearing cross-kingdom resemblance to some aspects of the dysbiosis that occurs in human inflammatory bowel disease. Bacterial community transplantation experiments demonstrated a causal role of a properly assembled leaf bacterial community in phyllosphere health. Pattern-triggered immune signalling, MIN7 and CAD1 are found in major land plant lineages and are probably key components of a genetic network through which terrestrial plants control the level and nurture the diversity of endophytic phyllosphere microbiota for survival and health in a microorganism-rich environment. Mutations in genes involved in immune signalling and vesicle trafficking cause defects in the leaf microbiome of Arabidopsis thaliana that result in damage to leaf tissues, suggesting mechanisms by which terrestrial plants control the level and diversity of endophytic phyllosphere microbiota.

Water quality, size, connectivity and other physical properties of hydrological systems might have different functions in the formation and maintenance of biodiversity, but this remains mostly unclear due to the lack of undisturbed sites for experimental modelling. Alpine freshwater habitats such as micro-waterbodies (MWB) represent a kind of natural system suitable for biodiversity research. In order to assess potential linkages between environmental factors, connectivity of MWBs and aquatic species richness, we conducted a pilot study in two separated MWB systems located in Gaoligong Mountain, northwest Yunnan province, China. A total of 27 MWBs have been analyzed, including 22 connected and 5 isolated bodies. 13 conventional environmental factors were tested while all kinds of aquatic macro-organisms were collected and classified. Results showed a high environmental heterogeneity among MWBs and significant differences between the two systems but only a few environmental variables such as the depth of soil bottom, total Nitrogen and altitude were related to species richness and the formation of the community structure. As a benefit from the high environmental heterogeneity, the cascaded MWB systems provided divergent habitats able to support species richness at a higher level than the same number of randomly selected MWBs. This finding supports the idea that habitat connectivity matters also in extremely small aquatic ecosystems. Moreover, although still a preliminary result, a polarization effect within connected chains where edge MWBs host higher taxa and endemic taxa richness as well as larger populations, was detectable. This study gives interesting insights on the spatial processes driving community structure and a new prospective for biodiversity conservation. Since alpine MWBs have significant effects on the maintenance of watershed biodiversity, further research on such small and crucial ecosystems is encouraged.

Rare earth oxides usually play an active role in modifying the microstructure and oxidation resistance of silicide coatings, but its modification mechanism has not yet been clarified. In this work, molybdenum silicide (MoSi2) coating with different contents of ytterbium oxide (Yb2O3) was fabricated using supersonic atmospheric plasma spraying, and its microstructural evolution and oxidation behavior were investigated. Experimental results shown that the morphological characteristics of produced SiO2-rich glass scale varied with the doping of Yb2O3, which noticeably affected the oxidation resistance of sprayed MoSi2-Yb2O3 coatings. All coated specimens exhibited a parabolic oxidation behavior, wherein the MoSi2-10 wt%Yb2O3 coating possessed the smallest parabolic constant and the lowest specific mass loss with 100 h oxidation at 1500 °C due to the absence of SiC-depleted region and the formation of continuous multicomponent compound scale. Given this, Yb2O3 additive with proper concentration not only guaranteed the sufficient filling of open spaces in SiO2 network by Yb3+ cations, but also strengthened the Si–O bonds to increasing the viscosity of SiO2 glass, thereby delaying the effective delivery of reactive oxygen species inwardly.

To date, the iron-catalyzed construction of C–heteroatom bonds has been less developed due to the difficulty of transmetalation with heteroatom anions and the sluggish reductive elimination. Herein...

Hydroxytyrosol is an antioxidant free radical scavenger that is biosynthesized from tyrosine. In metabolic engineering efforts, the use of the mouse tyrosine hydroxylase limits its production. Here, we design an efficient whole-cell catalyst of hydroxytyrosol in Escherichia coli by de-bottlenecking two rate-limiting enzymatic steps. First, we replace the mouse tyrosine hydroxylase by an engineered two-component flavin-dependent monooxygenase HpaBC of E. coli through structure-guided modeling and directed evolution. Next, we elucidate the structure of the Corynebacterium glutamicum VanR regulatory protein complexed with its inducer vanillic acid. By switching its induction specificity from vanillic acid to hydroxytyrosol, VanR is engineered into a hydroxytyrosol biosensor. Then, with this biosensor, we use in vivo-directed evolution to optimize the activity of tyramine oxidase (TYO), the second rate-limiting enzyme in hydroxytyrosol biosynthesis. The final strain reaches a 95% conversion rate of tyrosine. This study demonstrates the effectiveness of sequentially de-bottlenecking rate-limiting steps for whole-cell catalyst development., Whole-cell catalyst-based hydroxytyrosol production is low. Here, the authors increase the efficiency of its production in E. coli by de-bottlenecking two enzymatic steps catalyzed by monooxygenase and tyramine oxidase using structure-based enzyme redesign or in vivo-directed evolution with the aid of a newly developed biosensor.

Porous structured silicon has been regarded as a promising candidate to overcome pulverization of silicon-based anodes. However, poor mechanical strength of these porous particles has limited their volumetric energy density towards practical applications. Here we design and synthesize hierarchical carbon-nanotube@silicon@carbon microspheres with both high porosity and extraordinary mechanical strength (>200 MPa) and a low apparent particle expansion of ~40% upon full lithiation. The composite electrodes of carbon-nanotube@silicon@carbon-graphite with a practical loading (3 mAh cm−2) deliver ~750 mAh g−1 specific capacity, 92% capacity retention over 500 cycles. This work is a leap in silicon anode development and provides insights into the design of electrode materials for other batteries., The authors here construct hierarchical porous CNT@Si@C microspheres as anodes for Li-ion batteries, enabling both high electrochemical performance and excellent mechanical strength. The work highlights the importance of mechanical properties in developing battery materials for practical applications.

The solubility of N-acetyl-l-leucine in 12 mono organic solvents (methanol, ethanol, n-propanol, 2-propanol, 1-butanol, isobutanol, 2-butanol, methyl acetate, ethyl acetate, propyl acetate, acetone...

By introducing alkaline-earth metal ions (Mg2+, Ca2+, and Sr2+) as structure-directing agents, three new heterometallic complexes, Mg(H2O)6·[Cu2Mg(L)4(H2O)4]·4H2O (1), [CuCa(L)2(H2O)4]n (2) and [CuSr(L)2(H2O)4]n (3) [H2L = 4-(3-(pyridine-4-yl)-1H-1,2,4-triazol-5-yl)picolinic acid], have been synthesized under hydrothermal conditions and structurally characterized. H2L was in situ generated from hydrolysis of the well-known selective xanthine oxidase inhibitor topiroxostat. Complex 1 crystallizes in the space group P21/c and exhibits a zero-dimensional (0-D) structure containing the discrete [Mg(H2O)6]2+ cationic and [Cu2Mg(L)4(H2O)4]2– dianionic moieties. Complexes 2 and 3 are isostructural and crystallize in the space group C2/c, with one-dimensional (1-D) polymeric structure with infinite Cu(II)–Ca/Sr–carboxylate chains. The results reveal the significant influence of the alkaline-earth metal ions on the molecular structure. Their spectroscopic, thermal and solid-state luminescent properties have also been investigated.