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Cu2GeSe3 is an eco-friendly material, but pristine Cu2GeSe3 has poor thermoelectric properties. Here, the effects of magnetic Ni ion with unpaired 3d electrons on the electrical and thermal transport properties of Cu2GeSe3 are reported. Density functional theory (DFT) calculations indicate that the unpaired Ni 3d states cause the hybridization of Ni 3d orbitals with Se 4p orbitals near the Fermi level, giving rise to an increase in density of states (DOS). Combined with the significantly increased carrier concentration, a power factor (S2σ) value of ∼8.0 μWcm−1 K−2 at 723 K is achieved in Cu2Ge0.8Ni0.2Se3 sample, seeming to be the highest compared with the other Cu2GeSe3 systems. Meanwhile, the substitution of Ni for Ge causes the obvious local distortions in Cu2GeSe3 lattice, which yields the large strain fluctuations to suppress the lattice thermal conductivity. Consequently, a peak ZT value of ∼0.38 at 723 K is obtained in Cu2Ge0.9Ni0.1Se3 sample.

Bacillus cereus is a Gram-positive endospore-forming foodborne pathogen that causes lethal food poisoning and significant economic losses, usually through biofilm- and endospore-induced recurrent cross- and postprocessing contamination. Due to the lack of critical inhibitory targets and control strategies, B. cereus biofilm contamination is a problem that urgently needs a solution. In this study, the antibacterial and antibiofilm activities of several natural potential bacterial quorum sensing (QS) interferers, a group of spice-originated monoterpenoids, were screened, and terpinen-4-ol effectively inhibited B. cereus growth and biofilm and spore germination with minimum growth inhibition and 50% biofilm inhibitory concentrations of 8 and 2 μmol/mL, respectively. FESEM/CLSM and phenotypic research illustrated that in addition to a decrease in the number of attached B. cereus cells, (+)-terpinen-4-ol also obviously reduced extracellular matrix synthesis, especially exopolysaccharides, and inhibited the swarming motility and protease activity of B. cereus. (+)-Terpinen-4-ol did not exert a significant effect on AI-2 signals in B. cereus. Accordingly, the B. cereus-produced interspecies QS signals diffusing signal factors (DSFs, C8-C15) and diketopiperazines (DKPs) were detected and identified here, which suppressed B. cereus biofilm formation in a concentration-dependent manner. (+)-Terpinen-4-ol significantly increased the levels of specific DSF and DKP signals in B. cereus and down-regulated the gene expression of some rpfB homologues in transcription level. Moreover, both DKPs and DSFs inhibited swarming motility and protease activity in B. cereus, while just the DSF signals 2-dodecenoic acid and 11-methyl-2-dodecenoic acid inhibited exopolysaccharide synthesis like (+)-terpinen-4-ol. In summary, B. cereus strains were found to produce nine DSF- and six DKP-type QS signaling molecules, which repressed B. cereus biofilm formation. (+)-Terpinen-4-ol was confirmed to be a promising antibacterial and antibiofilm agent against B. cereus upregulating DSFs and DKPs levels, and it could target the critical genes rpfB for DSFs turnover.

Dietary cholesterol causes atherosclerosis along with a reduction of copper concentrations in the atherosclerosis wall. This study was to determine the relationship between aorta copper concentrations and the severity of atherosclerotic lesions as well as copper homeostasis in multiple organs in cholesterol-fed rabbits. Male New Zealand white rabbits, 10-week-old and averaged 2.0 kg, were fed a diet containing 1% (w/w) cholesterol or the same diet without cholesterol as controls. Twelve weeks after the feeding, aortic atherosclerotic lesions, serum cholesterol, and multiple organ copper concentrations were measured. Compared to controls, rabbits fed cholesterol-supplemented diet displayed higher serum cholesterol levels and developed atherosclerosis. Copper concentrations in the cholesterol-fed rabbits were increased in the serum and kidney but decreased in the atherosclerosis wall and multiple organs, including heart, liver, spleen, and lung. Furthermore, aorta copper concentrations negatively correlated, respectively, with the severity of the atherosclerotic lesion (r = - 0.64, p = 0.01), the microscope atherosclerotic lesion area (r = - 0.60, p = 0.02), and the stenosis of the lumen (r = - 0.54, p = 0.04). Dietary cholesterol not only causes atherosclerosis but also disturbs copper homeostasis in multiple organ systems. The negative correlation between aorta copper concentrations and the severity of atherosclerotic lesions suggests a vicious cycle between copper reduction and the pathogenesis of atherosclerosis. These changes in copper homeostasis would be additive to atherosclerosis as a risk factor for cardiovascular disease in humans.

Titanium dioxide nanoparticles (TiO2-NPs) are commonly used as food additives, including some high-fat foods that are risk factors for obesity. However, little is known about the effects of chronic TiO2-NPs digestion in the population on high fat diet (HFD). Herein, we reported that TiO2-NPs exacerbated HFD-induced obesity by disruption of mucus layer and alterations of gut microbiota. Oral intake of TiO2-NPs significantly increased body weight, liver weight, and amount of adipose tissues, especially in HFD-fed mice. Mechanistic studies revealed TiO2-NPs induced colonic mucus layer disruption and obesity-related microbiota dysbiosis. The damage on mucus was demonstrated through down-regulation of Muc2 gene and the absorption of mucin protein by TiO2-NPs. Consequently, mucus layer damage combined microbiota dysbiosis escalated the low-grade systemic inflammation, which exacerbated HFD-induced obesity. In contrast, gut microbiota depletion eliminated these effects, indicating gut microbiota were necessary for TiO2-NPs-induced inflammation and obesity. All the results stated the alarming role of TiO2-NPs in the HFD-driven obesity and emphasized the reevaluating the health impacts of nanoparticles commonly used in daily life, particularly, in susceptible population.

In this article, we will find centrosymmetric matrix solutions A of the left and right inverse eigenvalue problem under a submatrix A 0 constraint, where A 0 is also a centrosymmetric matrix. In ot...

Semiconductor-sensitized TiO2 thin films with long-term air stability are attractive for optoelectronic devices and applications. Herein, we demonstrate the potential of the TiO2 thin film (∼800 nm...

Nonstructural carbon (NSC), which represents the relationship between the carbon source and carbon sink, is an important factor that reflects the functions and performance of a tree. However, little is known regarding the time-series responses of NSC storage in evergreen species to different nitrogen (N) fertilization regimes. This study, which was based on a pot experiment, examined the response of the NSC (soluble sugars and starch) storage to different N addition intensities [light N addition (LN): 6.5 g N m−2 a−1; moderate N addition (MN): 13.0 g N m−2 a−1; and heavy N addition (HN): 26.0 g N m−2 a−1)] in saplings of the evergreen species Podocarpus macrophyllus. Our results showed that the net photosynthetic rate (Pn) under MN was significantly higher than that under LN, but was comparable to that under HN. Moreover, saplings subject to MN had a significant higher leaf biomass than that to LN and HN. These results indicated that the C supply via photosynthesis under MN was greater than that under LN and HN. The NSCs reserve under MN was considerable with that under LN, which suggested that saplings in MN group consumed higher and stored lower properties of NSCs than those in LN group. However, saplings under HN stored higher properties of NSCs than those under MN considering that no difference in NSCs pools was found between the two treatments. The leaf N concentrations were found in the increasing sequence of LN

The microstructure and texture in pure nickel were investigated during multi-step cross cold rolling (CCR) and subsequent annealing. It was found that the deformation texture in the CCR nickel was dominated by Brass and rotated Brass about normal direction (ND) (Bs ND ) texture components, along with marginal cube textures. The resulted deformation textures had a significant effect on the recrystallization behavior. Annealing of the CCR nickel at 550°C for 1 h led to the formation of dominant // ND fiber accompanied by minor rotated cube textures, rather than strong cube texture. Increasing the annealing temperature up to 800°C resulted in further enhancement of // ND fiber textures. The possible reasons for recrystallization behavior in annealed CCR sample were discussed based on in-situ annealing experiments from two aspects of oriented nucleation and oriented growth theories.

In this paper, we consider a linear constraint problem of Hermitian unitary symplectic matrices and its approximation. By constructing a simple unitary matrix U, we verify that Hermitian unitary sy...

Obesity is a worldwide public health issue, however, efficient strategies to treat obesity without systemic damage is still in serious lack. Herein, we proved that a significant decrease in body weight and abdominal circumference was observed when monosodium glutamate (MSG)-induced obese mice were orally treated with Coicis Semen formula. Consistently, computed tomography and magnetic resonance imaging results showed that both whole-body fat content and subcutaneous fat thickness were lowered, which was further confirmed by hematoxylin–eosin staining. In addition, the weight ratios of adipose tissues and liver to the body weight were reduced, due to the decreased lipid accumulation. The increased triacylglycerol, total cholesterol, and inflammatory cytokines could also be downregulated after the treatment. Furthermore, the neuronal injury marker and inflammatory cytokines in the hypothalamus were obviously reduced after the treatment, revealing that the protective effect of Coicis Semen formula on MSG-induced obesity was achieved by alleviating hypothalamic injury.

One of the challenging problems in robot navigation is efficient and safe planning in a highly dynamic environment, where the robot is required to understand pedestrian patterns in the environment, such as train station. The rapid movement of pedestrians makes the robot more difficult to solve the collision problem. In this paper, we propose a navigation probability map to solve the pedestrians&rsquo, rapid movement problem based on the influencer recognition model (IRM). The influencer recognition model (IRM) is a data-driven model to infer a distribution over possible causes of pedestrian&rsquo, s turning. With this model, we can obtain a navigation probability map by analyzing the changes in the effective pedestrian trajectory. Finally, we combined navigation probability map and artificial potential field (APF) method to propose a robot navigation method and verified it on our data-set, which is an unobstructed, overlooked pedestrians&rsquo, data-set collected by us.

• The evolution of l ‐DOPA 4,5‐dioxygenase activity, encoded by the gene DODA , was a key step in the origin of betalain biosynthesis in Caryophyllales. We previously proposed that l ‐DOPA 4,5‐dioxygenase activity evolved via a single Caryophyllales‐specific neofunctionalisation event within the DODA gene lineage. However, this neofunctionalisation event has not been confirmed and the DODA gene lineage exhibits numerous gene duplication events, whose evolutionary significance is unclear. • To address this, we functionally characterised 23 distinct DODA proteins for l ‐DOPA 4,5‐dioxygenase activity, from four betalain‐pigmented and five anthocyanin‐pigmented species, representing key evolutionary transitions across Caryophyllales. By mapping these functional data to an updated DODA phylogeny, we then explored the evolution of l ‐DOPA 4,5‐dioxygenase activity. • We find that low l ‐DOPA 4,5‐dioxygenase activity is distributed across the DODA gene lineage. In this context, repeated gene duplication events within the DODA gene lineage give rise to polyphyletic occurrences of elevated l ‐DOPA 4,5‐dioxygenase activity, accompanied by convergent shifts in key functional residues and distinct genomic patterns of micro‐synteny. • In the context of an updated organismal phylogeny and newly inferred pigment reconstructions, we argue that repeated convergent acquisition of elevated l ‐DOPA 4,5‐dioxygenase activity is consistent with recurrent specialisation to betalain synthesis in Caryophyllales., New Phytologist, 227 (3), ISSN:0028-646X, ISSN:1469-8137

Quantitively and stably tracking ion dynamics in the living brain of animals is essential to understanding many physiological and pathological processes. Solid-state ion-selective electrodes (ISEs) are powerful tools for monitoring the dynamic change of ions at physiological concentration range; however, the unintentional accumulation of an aqueous layer at the ion selective membrane/ solid contact interface compromises the electrode potential stability, limiting its in vivo application. Here, using manganese dioxide (MnO2) and potassium ISE (K+-ISE) as model solid contact and ISEs, we demonstrate for the first time that graphdiyne oxide (GDYO) can enhance the potential stability of solid contact-based ISEs. Our results suggest that the intrinsic structural and hydrophobic features of GDYO, plays a key role in impeding and stabilizing the formation of water layer. With GDYO-MnO2 acting as the solid contact, the K+-ISE displays an excellent short-term potential stability and maintains great selectivity, achieving reliable K+ sensing at the animal level. The GDYO-based strategy is generalizable to different ISEs and does not require complicated processing steps, paving an exciting opportunity for in vivo ion recognition and sensing.

The mechanical and anisotropic properties of BiM2VO6 (M = Mg, Ca and Cu) ceramics were explored using the first-principles calculations. The 3D (three dimensional) surfaces and 2D (two dimensional) projections of Young's modulus confirm that BiM2VO6 ceramics exhibit the strong anisotropy along the different directions. The minimum thermal conductivity on the different crystal planes strongly depends on the directions for BiM2VO6 ceramics. Three BiM2VO6 ceramics are anisotropic in sound velocities along the different directions. We hope that the present results will be useful for the further development and applications of BiM2VO6 ceramics.

Boneless pork shoulder were injected with marinate and treated with one of the three following curing treatments: (1) injection without tumbling, (2) vacuum tumbling, or (3) pressure-transform tumbling. The effect of pressure-transform tumbling treatment on porcine tissue microstructure, protein denaturation, water-holding capacity and textural properties of restructured pork chops was investigated. Results showed that pressure-transform tumbling with gas composition of CO2: N2 = 1 : 1 resulted in favorable yield of 118.22% of restructured pork chops. Tenderness was improved by 39% and 25% compared to the control group that was injected but not tumbled, and the vacuum tumbled group, respectively. Myofibers remained well-organized an the diameter was reduced by pressure-transform tumbling. FT-IR results showed that pressure-transform tumbling can modify protein conformation by increasing the amount of ɑ-helical and ẞ -sheet structures, but did not alter the secondary structure of proteins. The method has potential to benefit both consumers and manufacturers, by including reduction in processing time, improvement in product quality, and potential cost savings.

Alkaline Ni–Fe battery has attracted extensive attentions due to low cost, fast preparation and easy portability. However, the energy-storage capacity of Ni–Fe battery is greatly restricted by low active area and poor electronic conductivity, so it is highly desirable to design suitable electrode materials. In our work, Ni–Mn hydroxides/Ni3S2 (Ni2Mn1-S) nanohybrid with nanosheet structure was successfully fabricated via tuning the Mn content and reaction conditions. The orderly open structure, heterogeneous Mn atoms and even-distributed Ni3S2 phase not only generate more electrochemical active sites, but also significantly promote electronic conductivity, thus enhancing electrochemical performance of hybrid structure. Servered as supercapacitive electrode, the Ni2Mn1-S presents high capacitance (1386.8 C g−1 at 1 A g−1), excellent rate performance (71% retention at 30 A g−1) and suitable cycling stability (79% retention after 5000 cycles). After the coating of RGO nanosheet, the FeOOH@RGO electrode achieves high capacity performance (180 C g−1 at 1 A g−1) and rate performance (66% retention even at 10 A g−1). Furthermore, quasi-solid-state Ni–Fe battery was developed, utilizing a positive Ni2Mn1-S electrode and a negative FeOOH@RGO electrode. The hybrid device could achieve high energy densities (53.8 Wh kg−1 at 820 W kg−1 and 26.2 Wh kg−1 at 8200 W kg−1) and still maintain 75% capacitance after enduring 5000 cycles, which attributes to fast diffusion dynamics of Ni2Mn1-S and FeOOH@RGO electrodes.

Representation of clouds remains as the largest uncertainty in future climate predictions. Numerous studies have found and investigated the impacts of aerosols on cloud microphysical properties. However, few studies have investigated the process-level impact of aerosols on cloud microphysical properties, particularly over heavy polluted north China plain region. Using the aircraft observations, this study investigates the variation of cloud droplet size distribution (DSD) with aerosol concentration and vertical velocity (VV) in a shallow cumulus cloud with sufficient liquid water content (LWC). Strong variation in both cloud droplet number concentration (N) and LWC exists, with values from a few cm−3 to >1200 cm−3, and from 0 to 3.0 g/m3, respectively. In general, the total cloud N (effective radius re) for cases with weak VV is slightly less (smaller) than that for cases with high VV for this cumulus cloud with high LWC. Potential mechanisms about the impacts of aerosols (or VV) on the cumulus microphysical properties are proposed for both high and low LWC conditions. Simply said, the change of cloud N mainly depends on the amount of aerosols, and the change of cloud droplet re depends on both the supply of water content and the amount of aerosols: if LWC is high and aerosol amount is not too large, both cloud N and re increase with increasing aerosols; if LWC is low or if LWC is high but aerosol amount is too large, cloud N increase but re decrease with increasing aerosols. Note that for two cases with very strong downdraft, the cloud droplets seem less and smaller than strong VV cases. The most likely reason is that very strong downdraft along with the adiabatic cooling makes dry air above the cloud enter into clouds and causes evaporation of droplets, resulting in smaller and less cloud droplets.

In this paper, color-depth conditional generative adversarial networks (CDcGAN) are proposed to resolve the problems of simultaneous color image super-resolution and depth image super-resolution in 3D videos. Firstly, a generative network is presented to leverage the mutual information of the low-resolution color image and low-resolution depth image so that they can enhance each other considering their geometric structural similarity in the same scene. Secondly, three auxiliary losses of data loss, total variation loss, and 8-connected gradient difference loss are introduced to train this generative network to ensure that the generated images are close to the real ones in addition to the adversarial loss. Finally, we study the CDcGAN and its variants. Experimental results show that the proposed approach can produce the high-quality color image and depth image from a pair of low-quality images, and it is superior to several other leading methods. Additionally, it has also been used to resolve the problems of concurrent image smoothing and edge detection, as well as the problem of HR-color-image-guided depth super-resolution to show the effectiveness and universality of the proposed method.

In this study, different carbon nanomaterials (carbon nanotubes, solid carbon spheres and graphene nanosheets) for immobilizing bacterial small laccase (SLAC) to enable direct bioelectrocatalysis of oxygen reduction were comparatively investigated. Highest bioelectrocatalytic current response was achieved with ethanol-assisted SLAC adsorption on single-walled carbon nanotubes. Direct electron transfer (DET) rates were determined and generally shown to be larger with carbon nanomaterials in smaller dimensions or higher surface curvature, i.e., 1.92, 1.05, 1.52, 0.62 and 0.63 s−1 for adsorbed SLAC on single-walled carbon nanotubes (d = ca. 1.5 nm), double-walled carbon nanotubes (d = 2–4 nm), thinner multi-walled carbon nanotubes (d = 8–15 nm), thicker multi-walled carbon nanotubes (d = 20–30 nm) and graphene nanosheets, respectively. No obvious catalytic current response was obtained with solid carbon spheres (d > 200 nm). Surface nanostructures on electrodes with decreased cylindrical diameter could enable a favorable protein orientation of immobilized SLAC for efficient electronic communication between the catalytic copper sites and carbon nanomaterials as revealed by surface vibrational spectroscopy. Moreover, such a difference in DET kinetics of SLAC could be an outcome of synergic effects of surface properties (curvature, oxygen-containing groups, etc.) and conductivity of carbon nanomaterials. It is expected to offer useful information to fabricating carbon-based oxygen-reducing biocathodes of wide working pH range and high tolerance to chloride. Keywords: Small laccase, Carbon nanomaterials, Oxygen reduction, Direct electron transfer

First principles method were used to explore the structural stability, mechanical properties, anisotropic properties and thermodynamic properties of RETi2Al20 (RE = La, Ce, Gd and Ho) intermetallics. The calculated formation enthalpy and phonon frequencies indicate that RETi2Al20 intermetallics are satisfied with the structural stability. The elastic constants Cijs and elastic moduli (B, G, E) confirm that RETi2Al20 intermetallics possess the better elastic properties than pure Al. The values of B/G demonstrate that RETi2Al20 intermetallics are all brittle materials. The anisotropy in elastic constants, Young's modulus and acoustic velocities indicate that RETi2Al20 intermetallics are anisotropic and the degree of anisotropy of four compounds are larger than that of pure Al. Importantly, the calculated thermal quantities demonstrate that these RETi2Al20 intermetallics possess the better thermo-physical properties at high temperature.

The Triassic eastern Tethyan faunas have continued to yield numerous specimens of marine reptile taxa in recent years. Nevertheless, compared with other sauropterygian clades, the diversity of plac...

Glossy privet fruit and Ecliptae herba (GE) as formula was used as traditional Chinese medicine for liver diseases. However, systematic research of GE in liver injury has been explored rarely. Here, we comprehensively investigate the hepato-protective effects of the mixture of GE on different models. Our data indicated that GE administration decreased the levels of ALT and AST in serum compared with the model group. The histopathological changes were markedly alleviated in the GE treated groups. In addition, expression of cytokines including TNF-α, IL-6 and TGF-β in liver tissue associated with liver injury was elevated in the model groups, but significantly decreased after GE treatment. Furthermore, we explored that activation of Kupffer cells in liver tissue were suppressed after treatment with GE. Therefore, the major mechanism of the liver protective effects of GE may be attributed to the inhibition of Kupffer cell activation.

Various antibody-redirected immunotherapeutic approaches, including antibody-drug conjugates (ADCs), bispecific antibodies (bsAbs), and chimeric antigen receptor-T (CAR-T) cells, have been devised to produce specific activity against various cancer types. Using genetically encoded unnatural amino acids, we generated a homogeneous Her2-targeted ADC, a T cell-redirected bsAb, and a FITC-modified antibody capable of redirecting anti-FITC CAR-T (switchable CAR-T; sCAR-T) cells to target different Her2-expressing breast cancers. sCAR-T cells showed activity against Her2-expressing tumor cells comparable to that of conventional anti-Her2 CAR-T cells and superior to that of ADC- and bsAb-based approaches. To prevent antigen escape, we designed bispecific sCAR-T cells targeting both the Her2 receptor and IGF1R, which showed an overall improved activity against cancer cells with low Her2 expression. This study increases our understanding of various explored cancer therapeutics and underscores the efficient application of sCAR-T cells as a promising therapeutic option for breast cancer patients with low or heterogeneous antigen expression.

Land cover classification is one of the most fundamental tasks in the field of remote sensing. In recent years, fully supervised fully convolutional network (FCN)-based semantic segmentation models have achieved state-of-the-art performance in the semantic segmentation task. However, creating pixel-level annotations is prohibitively expensive and laborious, especially when dealing with remote sensing images. Weakly supervised learning methods from weakly labeled annotations can overcome this difficulty to some extent and achieve impressive segmentation results, but results are limited in accuracy. Inspired by point supervision and the traditional segmentation method of seeded region growing (SRG) algorithm, a weakly towards strongly (WTS) supervised learning framework is proposed in this study for remote sensing land cover classification to handle the absence of well-labeled and abundant pixel-level annotations when using segmentation models. In this framework, only several points with true class labels are required as the training set, which are much less expensive to acquire compared with pixel-level annotations through field survey or visual interpretation using high-resolution images. Firstly, they are used to train a Support Vector Machine (SVM) classifier. Once fully trained, the SVM is used to generate the initial seeded pixel-level training set, in which only the pixels with high confidence are assigned with class labels whereas others are unlabeled. They are used to weakly train the segmentation model. Then, the seeded region growing module and fully connected Conditional Random Fields (CRFs) are used to iteratively update the seeded pixel-level training set for progressively increasing pixel-level supervision of the segmentation model. Sentinel-2 remote sensing images are used to validate the proposed framework, and SVM is selected for comparison. In addition, FROM-GLC10 global land cover map is used as training reference to directly train the segmentation model. Experimental results show that the proposed framework outperforms other methods and can be highly recommended for land cover classification tasks when the pixel-level labeled datasets are insufficient by using segmentation models.

In this paper, an data-based H ∞ tracking control algorithm is studied for the discrete delay system with disturbances. The augmented system is constructed and then transformed into a data-based system consist of inputs, outputs, and reference trajectories, which replace the state vector by a data vector. Next, based on the Bellman optimality principle, the historical data is adopted to derive a new Bellman equation. In order to realize H ∞ tracking control, the input and disturbance are generalized to the zero-sum game problem. Finally, by collecting operational data online, a H ∞ tracking control method based on databased reinforcement learning algorithm is presented. Simulation example shows that the proposed reinforcement learning tracking control method is effective.

In this paper, we propose a pose refinement method based on the visible surface extraction of 3D object. Given a rough estimation of object pose, the algorithm of iterative closet point (ICP) is often used to refine the pose by aligning the object model with test scene. To avoid the interference of invisible points on the ICP process, we only use the visible surface for pose refinement. It is especially necessary when occlusion occurs in the scene. Combining the technologies of image rendering and depth consistency verification, the visible surface can be effectively extracted. During the process of pose refinement, hypothesis verification methods are also used to eliminate unreasonable hypothetical poses as early as possible. The proposed method is evaluated on the public Tejani dataset. The experimental results show that our method improved the average F1-score by 0.2062, which proves that our method can obtain pose estimation results of high accuracy, even in the occluded scene.

Ascorbic acid is a vital nutrient and antioxidant that is commonly used as an additive in commercial products. Quantitation of ascorbic acid is highly desired in the medical, food, and cosmetic industries. A spectrofluorometric assay for sensitive determination of ascorbic acid was developed using l-tyrosine as a fluorescent probe. The native fluorescence intensity of tyrosine was quenched using ascorbic acid. The linear range was 0.03-30.00 μM, and the limit of detection was 0.01 μM. The method exhibited excellent precision, accuracy, specificity, and robustness. Components of pharmaceutical preparations that are commonly found with ascorbic acid did not interfere with detection. The procedure was successfully employed for determination of ascorbic acid content in pharmaceutical tablets, injections, and nutrient supplements with satisfactory results. A Stern-Volmer plot and fluorescence lifetime revealed that quenching was attributed to the inner filter effect and static quenching. Isothermal titration calorimetry confirmed the formation of a complex between tyrosine and ascorbic acid, with a binding constant of 1.68 × 103 M-1 and reaction stoichiometry of 0.94. Thermodynamic parameters suggested spontaneous complexation via hydrophobic interactions as the dominant binding force. This method is promising for the simple and rapid determination of ascorbic in the pharmaceutical industry.

First principles calculations were used to explore the structural stability, mechanical properties, ductile or brittle behavior, anisotropic properties and thermodynamic properties of GdT2Al20 intermetallics. The calculated formation enthalpy and phonon frequencies indicate that GdT2Al20 intermetallics exhibit the structural stability. The elastic constants Cijs and elastic moduli (B, G, E) confirm that GdT2Al20 intermetallics possess the better elastic properties than pure Al. The values of Poisson's ratio v and B/G demonstrate that GdT2Al20 intermetallics are all brittle materials. The anisotropic constants, anisotropic figures (three and two dimensional figures) of Young's modulus and anisotropic acoustic velocities indicate that GdT2Al20 intermetallics are anisotropic, but the degree of anisotropy is small. Electronic properties confirm that the better elastic properties of GdT2Al20 intermetallics are attributed to the bond strength of Gd Al bond, Gd-T bond and T-Al metallic bonds. The calculated thermodynamic quantities demonstrate that GdT2Al20 intermetallics exhibit the better thermal physical properties than pure Al at high temperature.

Co9S8/Mo2S3 nanorods on CoS2 laminar arrays (CoS2-Co9S8/Mo2S3, defined as Co1Mo1) were synthesized via one step hydrothermal method for high performance supercapacitors. The Co1Mo1 hybrid was in-situ grown on Ni foam (NF). The nanorods and laminar arrays constructed 3D network with stable structure, maintaining high durability during electrochemical reactions. What’s more, this Co1Mo1 hybrid electrode combined the merits of both cobalt sulfides (the high capacity) and molybdenum sulfides (the excellent cycling stability). As expected, the Co1Mo1//NF hybrid exhibited excellent capacitance (2777.5 F g−1 at 1 A g−1), wonderful rate performance (81.46% from 1 to 50 A g−1), as well as superior stability (100% at 10 A g−1 after 8500 cycling) when used as single electrodes. The Co1Mo1//AC device was also assembled, showing high energy density (56.56 Wh kg−1 at the power density of 850 W kg−1). When combined two Co1Mo1//AC devices in series, six colored led bulbs which were in parallel can be lighted (green LED, working voltage greater than 3 V), further corroborated the possibility of the Co1Mo1 electrode for practical application. This study provided an easy and low-cost method for synthesizing electrode materials with excellent electrochemical performance.

Herein, the honeycomb-like Mn-doping Ni(OH)2/Ni3S2 nanohybrid is synthesized, via a one-pot hydrothermal reaction with multi-temperature adjustment. This distinct multi-temperature control achieves fast nanostructure transformation from thicker nanosheets to thinner nanosheets. The cross-linked honeycomb-like structure consists of abundant open space and internal ultrathin nanosheets. Meanwhile, the introduction of Ni3S2 and Mn-doping into Ni(OH)2 will generate synergistic effects in our nanohybrid. As expected, the nanohybrid electrode displays ultrahigh areal capacitance of 2518.8 mC cm−2 at a high current density of 1.2 mA cm−2, and still possesses a high value of 1027.7 mC cm−2 even at 120 mA cm−2. A hybrid supercapacitor was developed, which shows high energy density of 51.0 Wh kg−1 (at 425 W kg−1) and suitable cycling reversibility of 78.6% (after 5000 cycles). These results suggest this electrode material could serve as a promising candidate for energy-storage devices.

The exposure/biotransformation of inorganic arsenic (iAs) may perturb DNA methylation patterns and subsequently influence disease risk by altering the expression of key genes. Interindividual variation in patterns of DNA methylation can be explained by the influence of environmental, genetic, and stochastic factors. Here, we examined promoter DNA methylation levels with urinary arsenical concentrations and investigated the genetic and nongenetic determinants of DNA methylation in 105 samples collected from populations in Shanxi Province, China, with high levels of arsenic in drinking water. Arsenic concentrations in water were determined by atomic absorption spectrophotometry (AA-6800, Shimadzu Co., Kyoto, Japan). Urine samples were measured using an atomic absorption spectrophotometer with an arsenic speciation pretreatment system (ASA-2sp, Shimadzu Co. Kyoto, Japan) for detection. Gene-specific (CDH1, EREG, ERCC2, GSTP1, and MGMT) DNA methylation was quantified by targeted bisulfite sequencing. Single-nucleotide polymorphism (SNP) genotyping was performed using a custom-by-design 2 × 48-Plex SNPscan™ Kit. These results revealed CDH1 with promoter DNA methylation levels associated with iAs. After the exclusion of confounding factors, age was correlated with increased methylation of the CDH1 gene. The susceptibility of the CDH1 and GSTP1 gene promoters to methylation was increased in individuals carrying the DNMT3B (SNP rs2424932) GA genotype, and the susceptibility of the CDH1 gene promoters to methylation was increased in individuals carrying the DNMT3B (SNP rs6087990) TC genotype. Although the above results must still be replicated in larger samples, the findings improve our understanding of the pathogenesis of arsenic and may highlight certain DNA methylation markers as attractive surrogate markers for prevention research.

In order to achieve an intuitive interaction and visual semantic navigation for the indoor robot, we propose a novel object-aware hybrid map. The existing map is usually a metric map, lacking semantics for interaction. We combine objects in the indoor environment with the metric map to constitute a hybrid map. The map consists of a 3D object semantic map and a 2D occupancy grid map, which transfers human commands to the grid map through object semantics, thereby enabling autonomous navigation for the robot. We utilize ORB-SLAM2 for continuous pose estimation and 3D mapping. 2D object detection in key-frames is conducted based on YOLO v3. The object point clouds in multiple perspectives are merged and a 3D bounding box of the object is estimated. These objects construct a 3D semantic map. Furthermore, we project a 3D point cloud map into a 2D plane in order to get an occupancy grid map. Finally, these two maps are combined forming an object-aware hybrid map. We conduct experiments in real environments in order to verify the feasibility and robustness of the hybrid map for robot semantic navigation.

The discrete fracture-matrix model (DFM) technique has contributed to the rapid development of fracture modeling. In terms of vertical well modeling, however, the current well models fail to handle the field-scale DFM utilization. In this study, a pseudo inner-boundary model is presented tailored to this problem. Specifically, the modeling methodology consists of mesh generation and transmissibility evaluation. Regarding the mesh generation, the model handles the 2-D triangular-gridded matrix and 1-D edge-gridded fracture. The strict geometric analogy to generate triangles for the wellbore is abandoned, instead, the wellbore is approximated by a source/sink point and returns to a circular geometry when evaluating the transmissibility. The treatment sheds the limitation of triangle size and proves to boost the generation efficiency. Regarding the transmissibility evaluation, the derived formulations apply the radial/linear approximation for flow in matrix/fracture well-gridblock, and various conditions are considered, including gridblock geometry (triangle and rectangle), flow state (steady-state, unsteady-state and pseudosteady-state) and well completion (fully penetrating well and partially penetrating well). In addition, the compatibility with the star-delta transformation is discussed. By refining the well-gridblock into several sub-triangles, the formulations could be rapidly implemented to non-triangle-based DFM (e.g. PEBI, Cartesian). The model performance is demonstrated in eight validation cases. The model is shown to provide results in close agreement with those of reference in cases where the direct comparisons are performed.

Cactus-like ZnS/Ni3S2 (NZS) hybrid consisting of interconnected nanosheets with nanoparticles as a supercapacitor material has been designed and fabricated on 3D porous Ni foam through a facile two-step hydrothermal method. Benefiting from the combination of ZnS/Ni3S2 nanosheets with nanoparticles, the developed electrode exhibits an outstanding specific capacitance (2093 F g−1 at 1 A g−1), superior rate capability with 72% (10 A g−1). Moreover, the asymmetric supercapacitor (ASC) device applying the NZS as positive electrode material and activated carbon (AC) as negative electrode material has a voltage up to 1.7 V and thus delivers considerably higher energy density of 51.2 Wh kg−1 (at 849.4 W kg−1) than previous reports. The high energy storage characteristics of pseudo-capacitive are sufficiently attributed to the interconnected 3D network architecture of the NZS electrode along with nanoparticles, which provides the enlarged surface area with the high conductivity, facile and multi-access ion paths and increased electroactive sites in redox reaction.

The 137Cs activity in surface water of the East China Sea (ECS) was 0.66–1.36 Bq m−3 during May of 2011. The low activities were observed in the Changjiang Estuary and Zhejiang-Fujian coast and high activities were observed in the south offshore and Kuroshio Current pathway, suggesting that the influence from the current system in the ECS. The 134Cs were undetectable (

Rational design and synthesis of hybrid structures consisting with multiple pseudocapacitive components are challenging to develop materials with a high energy density for conversion and storage applications. Herein, a novel and cost-effective two-step method has been developed to synthesize three-dimensional (3D) nickel cobalt sulfides (Ni-Co-S)/Co(OH)2 nanocomposite with synergistic effect to provide an excellent comprehensive electrochemical performance, which shows a high specific capacitance (1560.8 Fg−1 at 1 A g−1) and outstanding rate capability (953.3 Fg−1 at 30 A g−1). Subsequently, an all-solid-state asymmetric supercapacitor (ASC) was successfully assembled using Ni1-Co2-S/Co(OH)2 nanocomposite as the positive electrode, activated carbon (AC) as the negative electrode and an alkaline PVA gel (PVA/KOH) as electrolyte. The Ni1-Co2-S/Co(OH)2//AC all-solid-state ASC device with a voltage window of 1.6 V delivered a maximum energy density of 48.8 W h kg−1 at a power density of 800 W kg−1 with excellent cycle stability. Excitedly, two all-solid-state ASCs assembled in series under fully charged can effectively light up four parallel connected light-emitting diodes (LEDs) for around 10 min, and can power a white LED (working voltage, 3.0–3.4 V) effectively. These remarkable electrochemical performances of Ni1-Co2-S/Co(OH)2//AC are beneficial to their practical applications for high-performance energy storage.

Herein, a facile hydrothermal method was designed to synthesize a novel structure of micro-flowers decorated with nanoparticles. The micro-flower structure consists of enormous cross-linked flat hexagonal nanosheets with sufficient internal space, providing fluent ionic channels and enduring volume change in the electrochemical storage process. As expected, the MnS/NixSy (NMS) electrode exhibits a relatively high specific capacitance of 1073.81 F g−1 (at 1 A g−1) and a good cycling stability with 82.14% retention after 2500 cycles (at 10 A g−1). Furthermore, the assembled asymmetric supercapacitor achieves a high energy density of 46.04 W h kg−1 (at a power density of 850 W kg−1) and exhibits excellent cycling stability with 89.47% retention after 10 000 cycles. The remarkable electrochemical behavior corroborates that NMS can serve as an advanced electrode material.

In our research, a two-step solid–liquid route was employed to fabricate flowery nickel–cobalt hydroxide with sulphur ion grafting (Ni1Co2–S). The utilization of NaOH/agar and Na2S/agar could efficiently retard the release rates of OH− or S2− ions at the solid–liquid interface due to strong bonding between agar hydrogel and these anions. Ni1Co2–S generally displays ultrathin flowery micro-frame, ultrathin internal nanosheets and expanded pore size. Besides, the introduction of suitable sulphide species into nickel–cobalt hydroxide could improve its conductivity due to the lower band gap of Ni–Co sulphide. The supercapacitive electrode Ni1Co2–S presented capacitance of 1317.8 F g−1 (at 1 A g−1) and suitable rate performance (77.9% at 10 A g−1 and 59.3% at 20 A g−1). Furthermore, a hybrid supercapacitor (HSC) was developed utilizing positive Ni1Co2–S and negative activated carbon electrodes. As expected, the HSC device exhibited excellent specific capacitance (117.1 F g−1 at 1 A g−1), considerable energy densities (46.7 W h kg−1 at 0.845 kW kg−1 and 27.5 W h kg−1 even at 9 kW kg−1) and suitable cycling performance, which further illuminated the high energy storage capacity of Ni1Co2–S.

Efficient, robust and safe energy storage systems occupy a vital position in the development of the electronics industry; they rely strongly on the rational design of electrode materials. In this manuscript, a one-pot hydrothermal route was employed to prepare sheet-membrane Mn-doped nickel hydroxide encapsulated via heterogeneous Ni3S2 nanoparticles. The inner large nanosheets, outer ultrathin membranes and encapsulated Ni3S2 nanoparticles construct a mechanically robust three-dimensional structure which provides abundant active sites to participate in electrochemical reactions. Density functional theory (DFT) calculations further reveal that the introduction of Ni3S2 and Mn-doping in nickel hydroxide obviously decrease the deprotonation energy and shorten the energy gap of Ni(OH)2, which greatly favors the electrochemical performance of the electrode material. When directly employed in a three-electrode alkaline supercapacitive electrode, NiMn-1 displays excellent capacitance of 385.6 mA h g−1 at 0.68 A g−1, enhanced rate performance (reaching 56.7% retention at 34 A g−1) and outstanding cycling stability (retaining 95.6% after 3000 cycles). Furthermore, a battery–supercapacitor hybrid device was developed based on this electrode material. The device also exhibits excellent capacitance of 59.7 mA h g−1 (at 0.47 A g−1), a high energy density of 51.5 W h kg−1 (at 404 W kg−1) and a suitable service lifespan. Therefore, this high-capacitance electrochemical performance endows the device with further advantages in the energy storage field.

The future of the power system is tied to the use of distributed generation (DGs) like photovoltaic (PV) and wind turbine (WT) since international societies are concerned regarding environmental pollution. However, the high penetration of distributed energy resources (DERs) in power systems causes a lot of control and operational problems that should be addressed by network operators. Therefore, this article proposes optimal management of a grid-connected microgrid (MG) including various DERs such as PV systems and storage devices. The use of the PV system in this MG is based on proposing new mathematical modelling. In the proposed model, the influence of radiation on different days and seasons on optimal operation is considered. Also, to overcome the random behaviour of the PV system, WT and loads, the uncertainties of the problem are modelled using the scenario method. The optimization problem is solved with the hybrid shuffled frog leaping and pattern search (HSFLA-PS) algorithm. The proposed optimal management is simulated by MATLAB/Simulink considering a practical PV model in a real environmental condition. This used algorithm has some advantages such as fast computational time and accurate results. The results show that the suggested day-ahead scheduling using the HSFLA-PS has an edge over other conventional methods.

Recently, aqueous zinc-ion batteries (ZIBs) are highly attractive due to high specific capacity of Zn, low-cost and safety, but the weak reaction kinetics and fast capacity attenuation still remain challenging. Herein, we adopt a temperature-regulation method to prepare rough Mn-doped zinc oxide microspheres. Such microsphere structure is rich in superfine nanoparticles and internal mesopores, which offers more Zn2+ diffusion channels and alleviates the stress and strain in the electrochemical process. Meanwhile, the doping of Mn into the ZnO structure can not only adjust the electronic structure, but also enhance the electrical conductivity, thereby upraising the reaction kinetics. Applied to ZIBs cathode, Mn-doped ZnO material presents appreciable rate performance, which obtains 268.1 mA h g−1 at 1 A g−1 and retains 163.8 mA h g−1 at 5 A g−1. Most importantly, high energy density (206.9 Wh kg−1), power density (6896.7 W kg−1) and superior cycle durability (~146.7% after 10 000 cycles relative to the first cycle) endow this material with more potential in energy storage.

Objective To clarify the urinary arsenic metabolism characteristics in individuals with essential hypertension and to analyze the relationship between lipid metabolism gene polymorphisms and susceptibility to essential hypertension in individuals in high-arsenic areas in western China. Methods A case-control study was conducted and involved individuals exposed to high arsenic levels (in this study, the arsenic content in the pressurized well water was 0–510.2 μg/L, and that in the mechanical well water was 167 μg/L) in two adjacent high-arsenic areas in Shanxi Province and the Inner Mongolia Autonomous Region, China. A total of 699 samples were collected, including 192 case samples (patients with hypertension) and 507 control samples (no hypertension). Blood pressure measurement data obtained from an epidemiological survey were used to determine whether the subjects had hypertension, and a logistic regression model was used to analyze the association between lipid metabolism gene polymorphisms and hypertension susceptibility. Blood and urine samples were collected based on epidemiological methods, single nucleotide polymorphisms (SNPs) were genotyped using a SNPscan™ multiple SNP typing kit, and urinary arsenic concentrations were determined using the hydride generation atomic fluorescence method (HG-AFS). Results ADIPOQ/rs266729 was the dominant genetic model [(GC + GG) vs CC = 0.686:1, 95 % CI = 0.478−0.983], and FABP2/rs1799883 was the recessive genetic model [TT vs (CC + TC) = 1.690:1, 95 % CI = 1.014–2.816]. The distribution of the urinary arsenic secondary methylation ratio (SMR) [dimethylated arsenic (DMA)/monomethylated arsenic (MMA)] was different between hypertensive patients and controls. Conclusion ADIPOQ/rs266729 and FABP2/rs1799883 polymorphisms affect susceptibility to essential hypertension in individuals exposed to high levels of arsenic; there was a clear difference in the urinary arsenic metabolism pattern between hypertensive patients and controls.

Cu3SbSe4, consisting of earth-abundant and inexpensive elements, is a promising p-type thermoelectric (TE) material. However, its thermoelectric performance is low in comparison with typical Pb-based materials. Here, we tune Ag content to optimize synergistically electrical and thermal transport properties for achieving high TE performance of Bi-doped Cu3SbSe4 materials. Dual-incorporation of Bi and Ag spontaneously generates multiple secondary phases involving CuSe and AgSbSe2. The multiscale defects including point defects, dislocations, nanoprecipitates and grain boundaries can enhance phonon scattering, thereby obtaining a low thermal conductivity (κ) of ~ 0.67 W m−1 K−1 at 673 K. The carrier concentration is improved due to the enhanced Cu vacancies caused by softening of Cu 3d–Se 4p bond after Ag doping, leading to the obviously increased electrical conductivity (σ). Meanwhile, the heavy element dopants (Bi and Ag) can modify the band structure to enhance Seebeck coefficient (S) by enlarging band gap (Eg) and increasing carrier effective mass (m*). The simultaneously enhanced σ and S result in a large power factor (S2σ) of ~1200 μW m−1 K−2 at 673 K. Consequently, a maximum ZT of ~1.18 (~136% higher than that of pristine Cu3SbSe4) at 673 K and an averaged ZT of ~ 0.51 at 300–673 K are achieved for Cu2.85Ag0.15Sb0.985Bi0.015Se4 sample due to a low κ and a high S2σ. This work offers a referential strategy to improve the comprehensive TE performance by dual-incorporation with isovalent heavy element doping for the diamond-like materials.

Constructing the supercapacitive materials which featured with abundant contact area and high conductivity is suitable for rapid ions/electrons transport. Herein, ultrathin Ni-Zn hydroxide nanosheets are vertically aligned on reduced graphene oxide (rGO) via MOF templates, and such sandwich-like structure is featured with abundant electrolytes-accessible contact sites. Introducing porous rGO substrate with excellent electronic conductivity can not only greatly accelerate the electron transfer between current collector and hydroxide, but also depress the agglomeration of hydroxide. Besides, heterogenous Zn element is also doped into the Ni-based hydroxide, which greatly optimizes the inherent electronic structure and conductivity of Ni-based hydroxide. Benefited from sandwich-like structure, the introduction of rGO and Zn doping, such Ni-Zn hydroxide/rGO material has harvested abundant contact sites and high conductivity. As a result, this supercapacitive material is featured with suitable capacitance (615.4C g−1 at 1 A g−1), appropriate stability (87.5% after 8000 cycles) and superior capacity rate property (62.3% retention at 30 A g−1). To well disclose the energy-storage feature of this material, a corresponding hybrid supercapacitor is manufactured, which presents a high capacity of 234.3C g−1 at 1 A g−1, superior capacity retention (89.7% retention after 10,000 cycles) and excellent energy density (53.7 Wh kg−1 at 825.1 W kg−1). These fascinating results demonstrate the excellent supercapacitive performance of this Ni-Zn hydroxide/rGO material.

Aqueous rechargeable zinc ion batteries (ARZIBs) are one of the promising electrochemical energy storage devices to overcome the worldwide energy challenge. However, the development of a suitable cathode with high energy/power densities and long cycle-life for ARZIBs is still a challenge. Here, a molybdenum disulfide/polyaniline (MoS2/PANI) hybrid with an inter-overlapped heterostructure is firstly explored as a superior cathode of ARZIBs. Its zinc intercalation chemistry is studied by combining means of ex-situ X-ray diffraction, ex-situ Raman, electrochemical analysis and density functional theory calculations. The results suggest an appropriate amount of PANI intercalation into MoS2 interlayer boosts the Zn2+ transport by expanding the interlayer spacing of MoS2 host and partially shielding the electrostatic interactions between Zn2+ and MoS2 host. Also, it enhances the charge transfer efficiency via reducing the bandgap between the conduction bands and valence bands of MoS2. As a result, the MoS2/PANI hybrid delivers a high reversible capacity of 106.5 mAh g − 1 at a current density of 1.0 A g−1 and retains 86% capacity after 1000 cycles.

Heat-resistant microbial contamination during soybean curd (dried tofu, SC) processing requires sterilization for food safety and shelf-life extension, which causes significant texture damage and adverse taste. In this work, SC texture stiffening was confirmed to be temperature dependent. 121 °C and 110 °C autoclaving caused over 2.0- and 1.5-fold increase of SC hardness, respectively, while 85 °C thermal treatment had no obvious impact on SC texture. Heat-resistant bacteria caused thermal treated SC spoilage, and high-throughput 16S rDNA gene sequencing analysis suggested that Bacillus, Clostridium, Lysinibacillus and Brevibacillus were the main contaminations. Furthermore, we made a comparative study on bacterial contamination of two different industrial SC processing lines, using viable colony counting, high-throughput 16S rDNA gene sequencing and MALDI-TOF-MS. Staphylococcus, Macrococcus, Psychrobacter, Bacillus and Acinetobacter were the predominant genera in each semi-finished product. These two processing lines showed very low planktonic and sedimented colony values. The air-exposed food contact surface introduced most non-spore forming contaminating bacteria, with the exception of Bacillus from coagulation. Although raw soybean and processing aids including coagulant and marinade also had low colony values, they introduced heat-resistant bacteria strains, which attached on pipelines and formed biofilms on tofu-coagulation cloth causing sustained and serious contamination in coagulation process.

Cobalt molybdate-based OER catalyst with open structure, high conductivity and rich oxygen vacancies was synthesized through a facile immersion and reduction way. This rGO-wrapped and Cu-decorated elctrocatalyst displays extremely low overpotential as 158 mV at 10 mA cm−2, and small Tafel slope as 38.4 mV dec−1 in contrast of the control groups with different Cu dosages, commercial RuO2 and other similar type OER catalysts. The enhanced high performance is primarily attributed to the formation of large amounts of heterogeneous interfaces and sufficient oxygen vacancies, which conduce to provide more active sites and tune the electronic structure, respectively.

Effective bifunctional catalysts are desirable to replace precious metal materials to promote the development of electrochemical water splitting. Facing with challenge, it is important to design and construct bifunctional electrocatalysts. Herein, we present a highly efficient multifunctional electrocatalyst, i.e., metal-organic framework derived Co3O4@Mo-Co3S4-Ni3S2/NF. (NF: nickle foam). Nano-flowers supported by the nanorods directly grown on the conductive substrate are achieved by doping non-3d high-valence metal Mo during the sulfurization process of ZIF-67 precursor. As a result, the obtained Co3O4@Mo-Co3S4-Ni3S2/NF heterostructure shows outstanding electrochemical performance. Specifically, the low overpotentials of 295 mV and 116 mV are obtained at the current densities of 50 mA cm−2 and 10 mA cm−2 for OER and HER in an alkaline solution, respectively. Moreover, Co3O4@Mo-Co3S4-Ni3S2/NF exhibited excellent catalytic activity with a current density of 10 mA cm−2 at a low voltage of 1.62 V for overall water splitting. This study may provide new methods for metal doping and rationally constructing heterostructure to improve electrochemical performance of catalysts, and is expected to help accelerate progress towards the non-precious metal electrocatalysts for overall water splitting.

Graphdiyne (GDY) is recently synthesized two-dimensional carbon allotrope with hexagonal rings cross-linked by diacetylene through introducing butadiyne linkages (-C≡C-C≡C-) to form 18-C hexagons and is emerging to be fundamentally interesting and particularly useful in various research fields. In this study, we for the first time find that GDY can be used as an electrode material with reactivity tunable by electronic states and surface chemistry of GDY. To demonstrate this, GDY is oxidized into graphdiyne oxide (GDYO) that is then chemically and electrochemically reduced into chemically reduced GDYO (cr-GDYO) and electrochemically reduced GDYO (er-GDYO), respectively. Electrode reactivity of GDY and its derivatives (i.e., GDYO, cr-GDYO, and er-GDYO) is studied with hexaammineruthenium chloride ([Ru(NH3)6]Cl3) and potassium ferricyanide (K3Fe(CN)6) as redox probes. We find that electron transfer kinetics of the redox probes employed here at GDYs depends on the density of electronic state (DOS) and the synergetic effects of the surface chemistry as well as the hydrophilicity of the materials, and that the electron transfer kinetics at cr-GDYO and er-GDYO are faster than those at GDY and GDYO, and quite comparable with those at carbon nanotubes and graphene and its derivatives (i.e., GO, cr-GO, and er-GO). These properties, combined with the unique electronic and chemical structures of GDY, essentially enable GDY as a new kind of electrode material for fundamental studies on carbon electrochemistry and various electroanalytical applications.

A study to develop a new system of negative temperature coefficient thermistors for wide temperature range, A series of Mn-based perovskite-structured ceramics of composition (LaMn1−x Al x O3)0.9(Al2O3)0.1 has been synthesized by conventional solid state reaction at 1350 °C. The X-ray diffraction patterns showed that for all the samples, the substitution of manganese by aluminum up to x = 0.1 preserved the rhombohedral perovskite LaMnO3-like phase. For x = 0.2, apart from the LaMnO3-like structure, a second perovskite phase based on the cubic LaAlO3 structure was formed. For x = 0.3 and 0.4, the phase present was LaAlO3 -type structure. The grain sizes of the sintered body detected by scanning electron microscope were decreased with increasing Al2O3 content. The resistivity increases with increasing the Al content. The obtained values of ρ 25 °C and B 25/50 and E a are in the range of 10–13103 Ω cm, 1813–2794 K, 0.156–0.241 eV, respectively. The resistance variation (ΔR/R) was