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[Display omitted] • The MAPbBr 3 -PdSe 2 heterojunction-based optoelectronic sensor demonstrates self-driven operation with a high specific detectivity up to 5.2 × 1011 Jones. • Under 0 V bias, the device exhibited a wide switchable range of optical responsivity from 137.5% to 27000%. • Simulating Pavlovian classical conditioned reflex experiments using electrical modulation have been realized, indicating the potential in adaptive machine vision. Neuromorphic optoelectronic sensors with in-sensor computing architecture hold great promise for applications that require processing large amounts of redundant data, such as the Internet of Things, robotics, and environmental sciences, due to their advantages of low time latency and energy efficiency. Halide perovskites, known for their extraordinary optoelectronic properties and stimuli-responsive characteristics, offer excellent opportunities for developing switchable visual sensors with high sensitivity, fast response, low energy consumption, and wide adaptive range. In this work, we successfully realized a MAPbBr 3 -PdSe 2 heterojunction-based optoelectronic sensor, demonstrating a responsivity of 28 mA/W and a high specific detectivity of 5.2 × 1011 Jones. A fast response time of ∼ 25 μs has also been achieved. Additionally, we investigated the role of voltage-induced ion migration in actively adjusting the device's photoresponse capacity. Under 0 V bias, the device exhibited a wide switchable range of optical responsivity from 137.5% to 27000%, significantly surpassing pure perovskite-based devices in previous reports. Moreover, we demonstrated the device's adaptive learning capabilities and reproducible switching characteristics by simulating Pavlovian classical conditioned reflex experiments using electrical modulation. These findings open up exciting possibilities for next-generation artificial vision systems that are energy-efficient, adaptive, and capable of learning and effectively responding to varying visual conditions. [ABSTRACT FROM AUTHOR]

The objective of the presented investigation was to determine the effects of microwave irradiation (MV irradiation) on the rheological characteristics of sewage sludge, and tried to explain the variation of apparent behaviors from a viewpoint of microcosmic composition. The results revealed that, from a macroscopic perspective, several rheological characteristics of sludge, including the apparent viscosity, limit viscosity and rheogram, were markedly changed by MV irradiation, and four rheological models ( Power law , IPC Paste , Casson and NCA/CMA Casson ) were found to be quite suitable for describing the rheological behaviors of sewage sludge before and after MV irradiation. However, from a microscopic perspective, MV irradiation effectively disintegrated multi-pole macromolecules contained in sludge, which reliably reduced the size of sludge particles and narrowed the particle size distribution. Even though the concentration of total solids increased following MV irradiation due to the evaporation of water, the content of macromolecules such as protein and polysaccharides in the remaining solids actually decreased. The changes in water content, chemical composition and particle size of sludge lead to variations of the total solids and the absolute value of zeta potential, which may be an essential reason for changing the rheological characteristics, including yield stress, thixotropy and apparent viscosity. [ABSTRACT FROM AUTHOR]

This work investigated the rheological behavior of sludge in a long-running digestor and established a timely approach for monitoring the torque information of an anaerobic process. With multi-methods, the rheological behavior of sludge within the digestor were revealed, which indicated that: (1) the on-line torque sensing approach was an efficient method to obtain timely torque signals, which could give a reliable prediction to the variation in the rheological behavior of sludge, and further provide useful information to monitor the operation of an anaerobic digestor; (2) the thixotropic index of sludge in the digestor decreased continuously along with the operational time, which showed a weakening tendency in the interaction among sludge particles; (3) both the content of total suspended solids (TSS) and extracellular polymeric substances (EPS) had close relationships with the limit viscosity of sludge, but TSS showed a positive impact, while, the impact of EPS was negative. [ABSTRACT FROM AUTHOR]

Cubic silicon carbide (3C-SiC) is the most promising material for active devices. Most researches of 3C-SiC epitaxial technology have been focused on chemical vapor deposition (CVD) in the past, but the growth rate of CVD is low. We attempt to grow epitaxial 3C-SiC on Si by sublimation method according to bulk sublimation growth technology. The typical sample is characterized by X-ray diffraction and Raman scattering spectroscopy. The results reveal that the sample is well crystalline. [Copyright &y& Elsevier]

In this paper the depth-sensing indentation (DSI) testing was used to study the elasto-plastic behavior and damage evolution in the surface layers of 304 stainless steel subjected to low-cycle fatigue loadings. For this purpose, the load–penetration depth ( P − h ) curves on the surface layers of cyclically deformed specimens corresponding to various stages of fatigue process were measured, from which the indentation characteristic parameters ( HV , S , h r and W p ) were extracted to evaluate the surface elasto-plastic behavior of the stainless steel during cyclic deformation. Based on the indentation characteristic parameters, the basic mechanical properties ( E , σ y and n ) were estimated using Dao et al.’s analysis algorithm to establish the constitutive descriptions of the fatigued surface layers. In terms of the continuum damage mechanics, a new damage indicator parameter, the indentation plastic work ( W p ), was proposed to characterize the fatigue crack-initiation damage for the stainless steel, and its evolution character during fatigue cycling was analyzed. In this study the deformation microstructures formed in near-surface regions of fatigued specimens were also examined using OM and TEM techniques to provide the micro-mechanisms for the surface mechanical behavior and fatigue damage evolution. It is finally suggested that the DSI testing could provide a potential nondestructive evaluation method for the early detection of fatigue damage of engineering components and structures in alternating service conditions. [ABSTRACT FROM AUTHOR]

Abstract: The Al–B co-doped 6H–SiC and heavily N-doped 6H–SiC crystals grown by physical vapor transport method were investigated in this paper, respectively. The XPS (x-ray photoelectron spectroscope), Raman spectra analysis and XRD (X-ray diffraction) were applied to characterize the obtained SiC crystals. When the co-doping level with a ratio of B:Al=0.22at.%:0.34at.% was obtained, Raman spectra results showed that there existed the 15R-polytype inclusion in the 6H–SiC crystal. When the co-doping ratio of B and Al increased to 1.18at.%:0.34at.%, there was only one polytype (6H) in the whole wafer. It can be speculated that the co-doping ratio of B:Al=1.18at.%:0.34at.% may stabilize the crystal structure during the 6H–SiC crystal growth process. But the real mechanism of the polytype stability is unclear. The role of Al or B or other impurities to influence polytype stability will be further investigated in the future work. Moreover, it has been found that a high nitrogen doping level can influence the polytype stability during the 6H–SiC crystal growth process. And especially, the 4H-polytype is preferred. [Copyright &y& Elsevier]

This work aims at revealing the key factors that limit the cleaner production level of a pickling process. By comparing the difference in their characteristics and the corrosion behaviors in an acidic medium, three kinds of sample, including the matrix steel (AS), the naturally-corroded carbon steel (NR) and the carbon steel treated under high temperature oxidation (OR), after immersed in the experimental solutions with or without hexamethylenetetramine (HA), were characterized with the methods, such as, electrochemical polarization, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Results indicated, no matter which kind of rust layers, the adsorption of HA on their surface all accorded with the same adsorption isotherm. Although the rust layers did not change the adsorption pattern of HA directly, but their steric effect would influence the adsorption potential of HA; the forming process of rust layers (under different environmental conditions) heavily influenced their composition, structure, and the interface roughness between the rust layer and the metal matrix, and also influenced the corrosion behavior of samples in an acidic medium, which were the key factors that limited the cleaner production level of a pickling process. These results indicated that an object-oriented pickling strategy should be adopted for a practical pickling process. [ABSTRACT FROM AUTHOR]

This work aims at revealing the adhesion characteristics and microbial community of the biofilm in an integrated moving bed biofilm reactor–membrane bioreactor, and further evaluating their variations over time. With multiple methods, the adhesion characteristics and microbial community of the biofilm on the carriers were comprehensively illuminated, which showed their dynamic variation along with the operational time. Results indicated that: (1) the roughness of biofilm on the carriers increased very quickly to a maximum value at the start-up stage, then, decreased to become a flat curve, which indicated a layer of smooth biofilm formed on the surface; (2) the tightly-bound protein and polysaccharide was the most important factor influencing the stability of biofilm; (3) the development of biofilm could be divided into three stages, and Gammaproteobacteria were the most dominant microbial species in class level at the last stage, which occupied the largest ratio (51.48%) among all microbes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mesoporous Ni 2 P-Cu 3 P nanocomposite with more active sites has been constructed. • Abundant heterogeneous interfaces have been designed to adjust electronic structures. • The microstructure related catalytic ability has been investigated. • The optimal Ni 2 P-Cu 3 P/GCE sensor exhibits excellent performance in glucose detection. The transition-metal phosphides with metalloid characterics, exhibiting great application potential in the field of glucose detection that plays an important role in the treatment of diabetes, can achieve high sensitivity as a eletrocatalyst for nonenzymatic glucose sensors. However, it has the drawbacks of low detection range and difficulty in manufacture. In this work, a hybrid heterogeneous nanocomposite of copper and nickel phosphide (Ni 2 P-Cu 3 P) has been designed and successfully prepared by a mild one-step solvothermal method. Inspired by the porous characteristic of sponges, the mesoporous structure with a much larger surface area has been constructed by adjusting the reaction conditions and the element composition of copper and nickel to have more active sites, thus broadening linear range. The precisely designed heterogeneous nanostructure and the unique mesoporous morphology of Ni 2 P-Cu 3 P were confirmed and characterized by the XRD and TEM analysis. Electrochemical oxidation of glucose on the composite modified glassy-carbon electrode (Ni 2 P-Cu 3 P/GCE) was measured by chronoamperometry and cyclic voltammetry. At the optimal test potential of + 0.64 V, the Ni 2 P-Cu 3 P/GCE hybrid electrode possessed an ultra-high sensitive response of 4700 μA mM−1 cm−2 to glucose, in a broad linear range from 4 μM to 5 mM, and a low detection limit of 0.1 μM at an S/N ratio of 3. The electrode also exhibits excellent anti-interference properties towards other common co-existing electroactive distractions, such as ascorbic acid, uric acid, urea, dopamine, etc. [ABSTRACT FROM AUTHOR]

Graphene/Ge/Si heterostructure were fabricated on Si(1 0 0) by direct transfer method. The monolayer graphene was transferred onto Ge/Si epilayer with the Raman intensity ratio (I 2D /I G ) of 1.75. The defect related D peak located at 1346 cm −1 is also very weak, signified the small amount of defects. Raman spectroscopy confirmed single crystal Ge film with S-K growth mode was obtained. The lattice mismatch between Ge and Si causes 0.8° off axis of Ge film. The growth mode of Ge film also confirmed as S-K mode when the growth temperature is higher than 650 °C, which cause a lower shift of Ge Raman shift peak. [ABSTRACT FROM AUTHOR]

Store-operated Ca2+ entry (SOCE) is a major mechanism of Ca2+ import from extracellular to intracellular space, involving detection of Ca2+ store depletion in endoplasmic reticulum (ER) by stromal interaction molecule (STIM) proteins, which then translocate to plasma membrane and activate Orai Ca2+ channels there. We found that STIM1 and Orai1 isoforms were abundantly expressed in human melanoma tissues and multiple melanoma/melanocyte cell lines. We confirmed that these cell lines exhibited SOCE, which was inhibited by knockdown of STIM1 or Orai1, or by a pharmacological SOCE inhibitor. Inhibition of SOCE suppressed melanoma cell proliferation and migration/metastasis. Induction of SOCE was associated with activation of extracellular-signal-regulated kinase (ERK), and was inhibited by inhibitors of calmodulin kinase II (CaMKII) or Raf-1, suggesting that SOCE-mediated cellular functions are controlled via the CaMKII/Raf-1/ERK signaling pathway. Our findings indicate that SOCE contributes to melanoma progression, and therefore may be a new potential target for treatment of melanoma, irrespective of whether or not Braf mutation is present. [ABSTRACT FROM AUTHOR]

Different defective structures of nitrogen-doped 6H-SiC single crystals were examined using a combination of laser scanning confocal microscopy (LSCM), scanning electron microscope (SEM) and KOH-KCO etching. The form, depth and size of the defects in etched silicon carbide (SiC) crystals were observed by LSCM. Using these 3D LSCM images, defective structures varying in the growth direction were observed from a side view for the first time. To study the size, depth and form of defect etch pits in detail, we observed the defect etch pits configuration in some volumes through taking 3D LSCM pictures. Information on defects obtained using this approach will be very helpful for investigation of MP and SD formation mechanism in conducting SiC substrates, as well as the observation of polytype stability in nitrogen-doped SiC crystals. [ABSTRACT FROM AUTHOR]

Affected by natural and anthropogenic disturbances such as forest fires, insect-induced mortality and harvesting, forest stand age plays an important role in determining the distribution of carbon pools and fluxes in a variety of forest ecosystems. An improved understanding of the relationship between net primary productivity (NPP) and stand age (i.e., age-related increase and decline in forest productivity) is essential for the simulation and prediction of the global carbon cycle at annual, decadal, centurial, or even longer temporal scales. In this paper, we developed functions describing the relationship between national mean NPP and stand age using stand age information derived from forest inventory data and NPP simulated by the BEPS (Boreal Ecosystem Productivity Simulator) model in 2001. Due to differences in ecobiophysical characteristics of different forest types, NPP-age equations were developed for five typical forest ecosystems in China (deciduous needleleaf forest (DNF), evergreen needleleaf forest in tropic and subtropical zones (ENF-S), deciduous broadleaf forest (DBF), evergreen broadleaf forest (EBF), and mixed broadleaf forest (MBF)). For DNF, ENF-S, EBF, and MBF, changes in NPP with age were well fitted with a common non-linear function, with R2 values equal to 0.90, 0.75, 0.66, and 0.67, respectively. In contrast, a second order polynomial was best suitable for simulating the change of NPP for DBF, with an R2 value of 0.79. The timing and magnitude of the maximum NPP varied with forest types. DNF, EBF, and MBF reached the peak NPP at the age of 54, 40, and 32 years, respectively, while the NPP of ENF-S maximizes at the age of 13 years. The highest NPP of DBF appeared at 122 years. NPP was generally lower in older stands with the exception of DBF, and this particular finding runs counter to the paradigm of age-related decline in forest growth. Evaluation based on measurements of NPP and stand age at the plot-level demonstrates the reliability and applicability of the fitted NPP-age relationships. These relationships were used to replace the normalized NPP-age relationship used in the original InTEC (Integrated Terrestrial Ecosystem Carbon) model, to improve the accuracy of estimated carbon balance for China’s forest ecosystems. With the revised NPP-age relationship, the InTEC model simulated a larger carbon source from 1950–1980 and a larger carbon sink from 1985–2001 for China’s forests than the original InTEC model did because of the modification to the age-related carbon dynamics in forests. This finding confirms the importance of considering the dynamics of NPP related to forest age in estimating regional and global terrestrial carbon budgets. [Copyright &y& Elsevier]

Currently, there are two types of measure in image classification accuracy assessment: pixel-level measures and category-level/map-level measures. These have their own limitations for representing the uncertainty at pixel and category/map levels. In addition, some of these measures derived from the error matrix are obtained by collecting reference data and then they may be affected by factors related to the sampling. This paper uses rough set theory to obtain the rough degree, rough entropy, quality of approximation and accuracy of approximation. Incorporating traditional measures, they compose one kind of three-level architecture for the classified image, which contains pixel-level measures, object/category-level measures and map-level measures. Unlike some conventional measures, these new measures can be derived directly from the supervised classification result without collecting reference data. A case study on the Landsat TM image is used to substantiate the conceptual arguments. The results demonstrate that the proposed measures are valid for measuring the accuracy of classified remotely sensed imagery and can provide additional information to conventional measures. [ABSTRACT FROM AUTHOR]

Intense photoluminescence (PL) has been observed at room temperature from the polycrystalline SiC samples prepared from carbon-saturated Si melt at a temperature ranging from 1500 to 1650°C. Composition and structure of the samples have been confirmed by means of X-ray photoelectron spectroscopy, X-ray diffraction and scanning electron microscopy. PL measurements with 325 nm UV light excitation revealed that the room temperature PL spectrum of the samples consists of 3 luminescent bands, the peak energies of which are 2.38 eV, 2.77 eV and 3.06 eV, respectively. The 2.38 eV band is much stronger than the others. It is suggested that some extrinsic PL mechanisms associated with defect or interface states would be responsible to the intensive PL observed at room temperature. [ABSTRACT FROM AUTHOR]