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In this work, cobalt-doped oxygen-vacancies-rich BiVO4(Co/BiVO4-Vo) was successfully synthesized for the degradation of tetracycline (TC) by activated peroxymonosulfate (PMS) under visible light. The morphologies, microstructures, and optical properties of the photocatalysts were analyzed in detail. Co/BiVO4-Voexhibited significantly enhanced degradation, removing 92.3% of TC within 10 min, which was greater than those of pure BiVO4(62.2%) and oxygen-vacancies-rich BiVO4(BiVO4-Vo) (72.0%), respectively. The photogenerated charge separation and transport properties were explored through surface photovoltage (SPV), photoluminescence spectrum (PL), and UV–vis diffuse reflectance spectroscopy (UV–vis DRS) measurements. Additionally, an in-depth investigation was conducted on the photocatalytically assisted advanced oxidation processes based on SO4•–(SR-AOPs) for the degradation of organic pollutants. The experimental results showed that the introduction of oxygen vacancies and Co doping achieved an effective separation of photogenerated carriers, which could accelerate the cycling between Co3+and Co2+and further activate PMS. The results of free radical capture experiments and electron spin resonance (ESR) experiments showed that reactive oxygen species (ROSs) such as 1O2, •O2–, and SO4•–played a dominant role in the removal of pollutants. This work provides a novel insight into the further development of efficient and rapid PMS photoactivators for environmental remediation of water bodies.

α-Fe2O3is a promising photoanode that is limited by its high surface charge recombination and slow water oxidation kinetics. In this study, we synthesized a TiO2layer on Ti-Fe2O3by annealing Ti-MOFs, followed by ZIF-67 as a co-catalyst, to fabricate a ZIF-67/TiO2/Ti-Fe2O3photoanode for photoelectrochemical (PEC) water splitting. The systematic experimental and theoretical results revealed that the improvement in performance was due to multiple effects of the MOF-derived TiO2. This molecule not only passivates the acceptor surface states of Ti-Fe2O3, thereby reducing the number of surface recombination centers, but also acts as an electron barrier to promote charge separation in the Ti-Fe2O3bulk. Moreover, MOF-derived TiO2can dramatically reduce the energy barrier for the OER of Ti-Fe2O3, thus promoting the conversion of the intermediate *OH into *O. The synergistic improvement in the bulk and surface properties effectively enhanced the water oxidation performance of Ti-Fe2O3. The ZIF-67/TiO2/Ti-Fe2O3photoanode exhibits a photocurrent density of up to 4.04 mA cm−2at 1.23 V vs. RHE, which is 9.4 times as that of pure Ti-Fe2O3, and has long-term stability. Our work provides a feasible strategy for constructing efficient organic-inorganic hybrid photoelectrodes.

Actuator fault will lead to the damage of vehicle driving ability. How to analyze the residual driving ability of the vehicle and use the residual driving ability to carry out targeted fault tolerance control (FTC) is the difficulty of FTC for automatic driving vehicles. In this article, an active FTC strategy for actuator fault of four wheels independent drive vehicles and a reference target reshaped scheme (RTRS) are proposed. The method consists of two parts. The first part calculates the limit of the vehicle's resultant longitudinal force, lateral force and yaw moment through the analysis of the friction limit between the tire and the ground and the vehicle's driving demand, which is called the driving capability feasible region (DCFR). Considering the impact of actuator fault on the tire force, the second analysis obtains the vehicle's residual driving limit, which is called the fault tolerant feasible region (FTFR). The upper Model Predictive Control (MPC) motion controller based on the FTFR and the lower allocation controller are designed to realize the FTC algorithm of the vehicle. The second part focuses on the fault scenes that can not be solved by a fault-tolerant controller alone. By weakening the driving task, priority is given to ensuring that the vehicle driving meets the driving capacity limit. The specific way is based on the optimization dynamic solution method, which comprehensively considers the FTC and the original reference target and uses the future output matrix equation of the upper MPC motion controller to design the optimization target to solve the feasible vehicle driving state, so as to achieve the RTRS. Carsim Simulink joint simulation is used to conduct FTC simulation of vehicle stability system actuator faults. The experimental results verify the effectiveness of the proposed FTC method and the RTRS to solve the problem of vehicle stability system actuator fault.

Objective: To investigate the effects of abdominal Tuina (Chinese therapeutic massage) on behavioral function, 5-hydroxytryptamine 1A receptor (5-HT1AR), and synapsin-1 (Syn1) in neonatal rats with hypoxic-ischemic brain injuries (HIBI). Methods: Forty healthy neonatal rats, born of 5 specific pathogen-free healthy pregnant rats, were randomly divided into a group for modeling (n=28) and a sham operation group (n=12) on the 7th day of birth. In the group for modeling, 24 neonatal rats with HIBI successfully established by the Rice method were randomly divided into a model group (n=12) and an abdominal Tuina group (n=12). The abdominal Tuina group was given abdominal Tuina for 28 d from 24 h after modeling, and the other groups were put under the same conditions but without any treatments. Rats in each group were subjected to suspension tests on the 7th, 14th, 21st, and 28th days of intervention. After the intervention, the rat hippocampal tissue was collected and stained with hematoxylin-eosin to observe the pathological changes in the rat hippocampal CA1 region. The 5-HT1AR expression in rat hippocampal CA1 region was detected by immunehistochemistry. The Syn1 expression in rat hippocampus was measured by Western blotting method. Results: The cells were disordered, and edema and necrosis appeared in the hippocampal CA1 region of the model group. Cell arrangement was clear, and edema was improved obviously in the hippocampal CA1 region of the abdominal Tuina group. Compared with the sham operation group, the suspension test scores, the number of 5-HT1AR positive cells, and Syn1 protein expression in the hippocampus decreased significantly in the model group after 21 d and 28 d of interventions (P<0.05). Compared with the model group, the suspension test scores, the number of 5-HT1AR positive cells, and Syn1 protein expression increased significantly in the abdominal Tuina group after 21 d and 28 d of interventions (P<0.05). Conclusion: Abdominal Tuina improves the behavioral function of upper limbs and up-regulates the expression levels of 5-HT1AR and Syn1 in the hippocampus of neonatal HIBI rats.

The conventional architecture of smart home is usually server-centric and this may cause many problems. The distributed architecture presented in this paper is based on multiple OSGi (Open Service Gateway Initiative) platforms. Relative home appliance services which are compliant with R-OSGi middleware for the home network system are also developed. The important aspect of R-OSGi is that it offers distribution transparency and uses the natural boundaries between software modules to establish the potential boundaries for distribution of the application. Experimental results obtained from the demo room show that the architecture is practical and reliable. Index Terms--Smart Home, R-OSGi, OSGi, Consumer Electronics, Residential Service Gateway.

The diversity of the carrier transport mechanism in the resistive switching process remains a significant obstacle for the design and application of resistive random access memory (RRAM) devices. In this study, the influence of annealing on the dielectric properties of the Ti/HfOx/Pt RRAM device and its associated carrier transport mechanism is investigated. The results reveal that the current conduction in both annealed and unannealed devices is primarily attributed to grain boundary (GB) relaxation, with only the GB acting as a depletion layer that induces dielectric relaxation. Furthermore, annealing decreases the interfacial polarization and changes the relaxation time at the GB. In addition, the charge carriers exhibit nearest‐neighbor hopping conduction at a higher temperature in Ti/HfOx/Pt RRAM devices, whereas variable‐range‐hopping conduction occurs at lower temperatures. Long‐range charge carrier transport also plays a significant role in the conduction process. To offer a deeper understanding of the conduction processes in the Ti/HfOx/Pt RRAM device, a carrier transport model is proposed, which provides valuable insights into the intricate mechanisms governing conduction in these devices. Nitrogen annealing decreases interfacial polarization at the grain boundary (GB) and changes GB relaxation time, which is the microscopic cause for annealing improving the performance of Ti/HfOx/Pt devices. The same charge carriers are responsible for current conduction and GB relaxation, with variable‐range hopping and nearest‐neighbor hopping transport at low and high temperatures, respectively.

The oxygen evolution reaction (OER) of Fe2O3is limited by its low photocarrier separation efficiency in photoelectrochemical (PEC) water splitting. How to construct an effective photocarrier transmission route in Fe2O3has become an important bottleneck for enhancing OER performance. Herein, we exploit a core–shell nanorod structure loaded with FeCo Prussian blue (FCP) to boost the water oxidation kinetics and charge transfer efficiency for the first time. As expected, the optimal γ-Fe2O3/α-Fe2O3photoanode exhibits a remarkable photocurrent density of 2.4 mA cm−2at 1.23 V vs.RHE; when a cocatalyst FCP is introduced as a hole-transport layer, it shows a photocurrent density of 3.5 mA cm−2at 1.23 V vs.RHE, which is 8.7 times higher than that of the pure α-Fe2O3. The outstanding photochemical performance could be attributed to the highest separation efficiency. A further study on the carrier lifetime was performed and clarified that the photocarrier lifetime of the γ-Fe2O3/α-Fe2O3/FCP photoanode is prolonged (∼50.64 ps) as compared to that of the pure α-Fe2O3photoanode (∼21.00 ps) using femtosecond time-resolved absorption spectroscopy (fs-TAS). This work successfully explains the photocatalytic water oxidation mechanism in the γ-Fe2O3/α-Fe2O3/FCP photoanode and provides an effective insight into designing a photocarrier delivery channel for the outstanding water oxidation.

Z-scheme photocatalytic system has been regarded as a popular field of research in photoelectrochemical (PEC) water splitting. Among the many obstacles facing a Z-scheme photocatalytic system, the analysis methods of interfacial Z-scheme charge transfer still remain a significant challenge. Hence, in this study, CdS/Ti-Fe2O3heterojunction photoanodes are elaborately designed to explore the charge-transfer behavior in PEC water splitting. In this study, photophysical measurements, including the Kelvin probe measurement, surface photovoltage spectroscopy (SPV), and transient photovoltage spectroscopy (TPV), are used to monitor the migration behavior of photogenerated charges at the interface electric field of CdS/Ti-Fe2O3Z-scheme heterojunction photoanodes. The Kelvin probe and SPV measurements demonstrate that CdS/Ti-Fe2O3interfacial driving force favors the rapid transfer of photoexcited electrons to CdS. The double-beam strategy based on TPV indicates that more electrons of Ti-Fe2O3are combined with the holes of CdS owing to the intensive interface electric field. The results of these measurements successfully prove the Z-scheme migration mechanism of CdS/Ti-Fe2O3photoanodes. Benefiting from the desirable charge transfer at the interface electric field, CdS/Ti-Fe2O3photoanodes exhibit superior photocatalytic oxygen evolution reaction performance compared with that of pure Ti-Fe2O3. The photocurrent density of the 25CdS/Ti-Fe2O3photoanode reaches 1.94 mA/cm2at 1.23 V versus reversible hydrogen electrode without excess cocatalyst, and it is two times higher than that of pure Ti-Fe2O3photoanode. Therefore, an outstanding strategy is provided in this study to prove the Z-scheme charge-transfer mechanism of photocatalytic systems in PEC water splitting.

The growth of anatase TiO2 nanowires (NWs) on fluorine doped tin oxide (FTO) substrates through hydrothermal reaction has attracted wide attention and research, especially in the case of the solar cells. Actually, the built-in electric field at anatase TiO2 NWs/FTO interface leads the photoexcited holes transfer to FTO conductive substrates because the Fermi energy of anatase TiO2 NWs film is higher than that of FTO substrates. But efficient transport of photoexcited electron to the FTO conductive substrates is desirable. Hence, the built-in electric field at pure TiO2 NWs/FTO interface has prevented anatase TiO2 NWs based solar cells from achieving a higher photoelectric performance. In this work, we elaborately design and construct the N-doped anatase TiO2 NWs/FTO interface with the desirable orientations from FTO towards N-doped anatase TiO2 NWs, which favors the photoexcited electron transfer to the FTO conductive substrates. The surface photovoltage (SPV) and Kelvin Probe measurements demostrate that the N-doped anatase TiO2 NWs/FTO interface favors the photoexcited electron transfer to the FTO conductive substrates due to the fact that the orientation of built-in electric field at the N-doped TiO2 NWs/FTO interface is from FTO towards TiO2. The photoexcited charge transfer dynamics of CdS QD-sensitized TiO2 NWs and N-doped TiO2 NWs electrodes was investigated using the transient photovoltage (TPV) and transient photocurrent (TPC) technique. Benefiting from the desirable interface electric field, CdS based quantum dot-sensitized solar cells (QDSCs) with the optimal N doping amount exhibits a remarkable solar energy conversion efficiency of 2.75% under 1 sun illumination, which is 1.46 times enhancement compared with the undoped reference solar cells. The results reveal that the N-doped anatase TiO2 NWs electrodes have promising applications in solar cells.

Astragalus variabilis Bunge is a widespread locoweed that threatens livestock production in desert grassland. No research has reported its possible ecological functions due to focus being on its negative effect on livestock production. This study aimed to assess the effects of A. variabilis on soil properties and its possible role in improving soil quality in desert grassland. Soil samples were collected in Astragalus patches and the adjacent bare patches over two successive growing seasons in Alxa desert grassland where A. variabilis was favoured to spread. Soil properties including texture, water content, dry bulk density, porosity, available nutrients, organic matter, and soil microbial biomass were determined at 15 study sites. There was no significant difference in soil texture between Astragalus-dominant and bare patches; but organic matter (OM), available N and P, and microbial biomass in surface soil (0–30cm) were significantly higher in Astragalus patches. Furthermore, microbial biomass showed a significantly positive correlation with available nutrients and OM. Levels of water soluble salt were significantly lower in A. variabilis surface soils under drought conditions. Results suggested that A. variabilis was associated with some positive changes in soil properties, and was potentially important in improving soil chemical and microbial properties in desert grassland ecosystems. Consequently, total elimination of locoweed should not necessarily be considered the best solution to locoweed poisoning in livestock.

ABSTRACTLong noncoding RNA small nucleolar RNA host gene 10 (SNHG10) has been suggested to function as tumor promoter in various human cancer types. Herein, the role of SNHG10 in colorectal cancer (CRC) was explored. Expression levels of genes in colorectal cancer tissues and cell lines were detected by Starbase and reverse transcription quantitative PCR (RT-qPCR) Cell Counting Kit-8 (CCK-8), the BrdU incorporation assay and Transwell assays were explored to study the function of SNHG10 in HCT116 and DXH-1 cells. In addition, the interaction of SNHG10 and miR-3690 was analyzed by dual-luciferase reporter assays. SNHG10 had a high expression level in CRC tissues and cell lines. Meanwhile, knockdown of SNHG10 reduced cell viability, inhibited cell proliferation and decreased cell migration and invasion. Moreover, bioinformatics analysis revealed that one potential target gene of SNHG10 was miR-3690. Dual-luciferase reporter assay confirmed that miR-3690 directly targeted SNHG10. Importantly, SNHG10 could decrease the expression of miR-3690 in HCT116 and DXH-1 cells. More importantly, the silencing of miR-3690 reversed the effect of the SNHG10 knockdown on the cell viability, proliferation, migration and invasion of HCT116 and DXH-1 cells. The present results demonstrated that SNHG10 promotes colorectal cancer cells the malignant progression by targeting miR-3690.Abbreviations: CRC: Colorectal cancer; Lnc RNA: Long noncoding RNA; microRNAs: miRNAs/miRs; RT-qPCR: reverse transcription quantitative polymerase chain reaction; CCK-8: Cell Counting Kit-8

The wearable and integrated sensing platform is a promising choice for developing real-time analytic electronics with clear advantages but still poses challenges, such as the realization of high precision, low limit of detection (LOD), moderate mechanical capacity, integration, and miniaturization. In this work, a simple printed wearable smartsensor has been fabricated with the aid of electrochemical plating methods with bismuth (Bi) films. The excellent sensing behaviors, including linear relationship, selectivity, stability, repeatability, and the LOD at ppb levels, have been obtained by this smartsensor. Additionally, the highly flexible textile-based sensor exhibits potential application on the substrates of daily cloth, sports T-shirt, and sports wristbands, and it maintains good stability under repeated deformations of washing and twisting. Importantly, integrated with printed circuit board, single chip micyoco, and Bluetooth modules, a smartsensing platform is successfully acquired for real-time detection of heavy metals (e.g., Zn, Cd, Pb, etc.). Finally, actual samples of human sweat, seawater, cosmetics, and drinking water have been remotely successfully demonstrated for detection by this smartsensor, enabling a great promise for fast on-site screening of samples in practical application.

Modifying inexpensive cocatalysts on semiconductors to accelerate the charge transfer at the photoanode/electrolyte interface, which possess good charge transfer in the bulk photoanode simultaneously, is priority among priorities in constructing low-cost and efficient PEC solar energy conversion devices. However, it is often difficult to satisfy outstanding charge transfer both in the bulk and at the photoanode/electrolyte interface when integrating cocatalysts with semiconductors. In our work, we synthesized FeP-decorated Ti–Fe2O3in situthrough simple low-temperature phosphidation, which possessed good interfacial contact between Ti–Fe2O3and FeP. The results demonstrated that the in situdeposition of FeP not only reduced the charge transfer resistance in the bulk photoanode by improving the electrical conductivity, but also accelerated the charge transfer at the photoanode/electrolyte interface. Based on the above advantages, the novel FeP/Ti–Fe2O3exhibited splendid photocurrent density as high as 3.9 mA cm−2at 1.23 V vs.RHE; meanwhile, the onset potential of FeP/Ti–Fe2O3shifted cathodically to 0.88 V vs.RHE in comparison with that of Ti–Fe2O3(0.98 V vs.RHE). This work paves a simple path to construct a cocatalyst-modified photoanode with excellent interfacial charge transfer and offers a low-cost and promising cocatalyst that can be applied in the photoelectrochemical water oxidation reaction.

Drought stress limits the growth and development of grapevines, thereby reducing productivity, but the mechanisms by which grapevines respond to drought stress remain largely uncharacterized. Here, we characterized a group A bZIP gene from “Kyoho” grapevine, VlbZIP30, which was shown to be induced by abscisic acid (ABA) and dehydration stress. Overexpression of VlbZIP30in transgenic Arabidopsis thalianaenhanced dehydration tolerance. Transcriptome analysis revealed that a major proportion of ABA-responsive and/or drought-responsive genes are transcriptionally regulated by VlbZIP30during ABA or mannitol treatment at the cotyledon greening stage. We identified an A. thalianaG-box motif (CACGTG) and a potential grapevine G-box motif (MCACGTGK) in the promoters of the 39 selected A. thalianagenes upregulated in the transgenic plants and in the 35 grapevine homologs, respectively. Subsequently, using two grapevine-related databases, we found that 74% (23/31) and 84% (21/25) of the detected grapevine genes were significantly upregulated by ABA and drought stress, respectively, suggesting that these genes are involved in ABA or dehydration stress and may be regulated by VlbZIP30in grapevine. We propose that VlbZIP30functions as a positive regulator of dehydration-responsive signaling in the ABA core signaling pathway. Researchers in China have identified a key gene involved in drought resistance in grapes. After exposing grape plants to drought, Xiping Wang’s team at Northwest A&F University observed increased expression of the VlbZIP30gene. VlbZIP30expression also increased in response to the plant hormone ABA, a known regulator of stress response. Further investigation demonstrated that VlbZIP30probably regulates ABA signaling, though its precise activity remains unclear. The researchers discovered a genetic sequence consistently present in the promoters of genes activated by VlbZIP30. They also identified over 30 genes regulated by VlbZIP30. While many of these genes are probably involved in drought tolerance, more work will be needed to clarify their functions. These findings may serve to guide efforts to breed or engineer grape varieties with improved drought tolerance.

The overall water splitting into hydrogen and oxygen is one of the most promising ways to store intermittent solar and wind energy in the form of chemical fuels. However, this process is quite thermodynamically uphill, and thus needs to be mediated simultaneously by efficient hydrogen evolving and oxygen evolving catalysts to get any feasible output from it. Herein, we report the synthesis of such a catalyst comprising ultrasmall NixCo3−xS4-decorated Ni3S2nanosheet arrays supported on nickel foam (NF) viaa partial cation exchange reaction between NF-supported Ni3S2nanosheet arrays and cobalt(II) ions. We show that the as-prepared material, denoted as NixCo3−xS4/Ni3S2/NF, can serve as a self-standing, noble metal-free, highly active and stable, bifunctional electrocatalyst for the two half reactions involved in the overall water splitting: the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). Furthermore, we demonstrate that a high-performance electrolyzer for the overall water splitting reaction can be assembled by using NixCo3−xS4/Ni3S2/NF as the electrocatalyst at both the cathode and the anode sides of the electrolyzer. This electrolyzer delivers water-splitting current densities of 10 and 100mA/cm2at applied potentials of 1.53 and 1.80V, respectively, with remarkable stability for >200h in both cases. The electrolyzer's performance is much better than the performances of electrolyzers assembled from many types of other bifunctional electrocatalysts as catalyst couple. Moreover, the overall performance of the electrolyzer is comparable with the performances of electrolyzers containing two different, benchmark, monofunctional HER and OER electrocatalyst couple (i.e., Pt/C-IrO2).

AbstractBackground: Zinc oxide nanoparticles (ZnO NPs) are increasingly being used in industry.Objective:To evaluate the acute toxicology of ZnO NPs in Mice.Methods: ZnO NPs were intratracheally instilled into mice at different dose (200, 400, 800 μg/kg), which was 1, 2, or 4 times of accumulative intake in one week according to the threshold limit value. Acute toxicity was assessed by animal mortality, organ/body weight ratios, hematology, blood biochemistry, and histopathology as well as by the determination of cells, proteins, and lactate dehydrogenase activity in bronchoalveolar lavage fluid.Results: Exposure to ZnO NPs also resulted in bodyweight loss and a higher level of total cell number, total protein, and hydroxyproline content in BALF. Nitric oxide and malondialdehyde levels in the lung homogenates were also increased. In addition, inflammatory and hyperplastic changes in the lungs were observed.Conclusion:Threshold limit value (5 mg/m3) may unfit for ZnO NPs.

We investigated the effect of nitrogen–hydrogen (NH) mixed plasma pretreatment of 4H–SiC surfaces on SiC surface properties, SiO2/SiC interface quality, and the reliability and voltage stability of metal–oxide–semiconductor (MOS) capacitors. The NH plasma pretreatment decreased the incomplete oxide and contaminants on the SiC surface and reduced the density of SiO2/SiC interface traps. Compared with the untreated sample, the dielectric insulating characteristics and reliability of samples pretreated by NH plasma were improved. We also demonstrated that the shift/hysteresis of the flat band voltage (Vfb) and the midgap voltage (Vmg) induced by bias temperature stress for SiC MOS capacitors after NH plasma pretreatment was significantly decreased. Furthermore, the mechanisms of NH plasma pretreatment to improve interface properties and device performances were determined by combining secondary ion mass spectrometry (SIMS) measurements, X-ray photoelectron spectroscopy (XPS), and first-principles calculations. The result indicates that the excessive oxidation at the SiO2/SiC interface was limited due to the reduction in the diffusion of oxygen atoms into SiC caused by the surface Si–H and Si–N; NH plasma pretreatment suppressed the generation of interfacial traps by reducing surface pollutants and passivating surface defects, and some N atoms introduced into the SiO2/SiC interface effectively passivated the interfacial electroactive traps.

AbstractThe photocatalytic activity of cobalt phthalocyanine (CoPc) immobilized onto MCM-41 was investigated for decomposition of methyl orange in aqueous solutions. The morphology and structure of the catalyst were analyzed by diffuse reflectance ultraviolet-visible (DR UV–vis), X-ray diffraction, Fourier transform infrared, and scanning electron microscopy (SEM). Photocatalytic efficiency of the prepared catalyst for degradation of methyl orange was tested under illumination of visible light. The photodegradation process is completed within 2 h using a dose of 0.04 g/L of the catalyst in the 0.05 g/L of methyl orange solution under Xenon lamp, and the removal rate was 98.3%. The obtained results revealed that the photocatalyst was very active in degradation of methyl orange.

Despite the superior oxygen evolution electrocatalytic activity of metal-selenide nanostructures, especially when compared with their oxide counterparts, the origin behind their excellent activity remains unclear. Herein, we conduct a thorough and meticulous study on the NiSe oxygen evolution nanoelectrocatalyst—a representative metal selenide that was recently reported to be effective for the oxygen evolution reaction (OER). Our results unambiguously show that NiSe undergoes deselenization under electrocatalytic conditions, finally in situtransforming into a NiSe/NiOxcore/shell nanostructure; the latter core/shell nanomaterial gives a superior activity towards OER. The NiSe/NiOxnanomaterial affords a current density of 10 mA cm−2at an overpotential as low as ∼243 mV, outperforming most of the previously reported nickel (hydro)oxide OER electrocatalysts. These results further imply that the electrocatalytic activity of the so-called NiSe catalysts should originate from the in situformed amorphous NiOxshell in nature, with the NiSe core having some auxiliary effects on the catalytic activity. Additionally, the NiSe/NiOxnanomaterial is also found to show a higher electrocatalytic activity than NiSe itself for the hydrogen evolution reaction (HER) in basic media.

Increasing the number of active sites of a non-noble metal catalyst is an effective route to make its overall catalytic performance close to that of noble metals. Herein, we report a novel confinement strategy for preparing well-dispersed octahedral CoS2nanocrystals through in situsulfidization of the carbon fibre-wrapped Co nanoparticles, in order to fully expose the active sites of every nanocatalytic unit. The successful synthesis of the material includes three main steps: (i) electrospinning synthesis of Co ion-containing polyacrylonitrile fibres (Co2+-PANF), (ii) thermal conversion of the Co2+-PANF at 900 °C under N2atmosphere into a Co-embedded carbon fibre network (Co-CFN), and (iii) direct sulfidization of Co-CFN using sublimed sulphur, leading to the confinement growth of CoS2nano-octahedra on CFN. Furthermore, this material, denoted as CoS2-CFN, can serve as a highly active, stable, non-noble metal electrocatalyst for hydrogen evolution reaction in acidic medium. This material generates a current density of 10 mA cm−2at a small overpotential of 136 mV with about 100% Faradaic yield and maintains its catalytic activity for at least 20 hours. The excellent catalytic properties of CoS2-CFN are attributed primarily to the synergistic effects of the intrinsic catalytic ability of CoS2, the well-dispersed CoS2nanocrystals as the catalytically active phase, as well as the high conductivity and porous structure of the carbon fibre network as a support material.

Splitting water to produce hydrogen requires the development of non-noble-metal catalysts that are able to make this reaction feasible and energy efficient. Herein, we show that cobalt pentlandite (Co9S8) nanoparticles can serve as an electrochemically active, noble-metal-free material toward hydrogen evolution reaction, and they work stably in neutral solution (pH 7) but not in acidic (pH 0) and basic (pH 14) media. We, therefore, further present a carbon-armoring strategy to increase the durability and activity of Co9S8over a wider pH range. In particular, carbon-armored Co9S8nanoparticles (Co9S8@C) are prepared by direct thermal treatment of a mixture of cobalt nitrate and trithiocyanuric acid at 700 °C in N2atmosphere. Trithiocyanuric acid functions as both sulfur and carbon sources in the reaction system. The resulting Co9S8@C material operates well with high activity over a broad pH range, from pH 0 to 14, and gives nearly 100% Faradaic yield during hydrogen evolution reaction under acidic (pH 0), neutral (pH 7), and basic (pH 14) media. To the best of our knowledge, this is the first time that a transition-metal chalcogenide material is shown to have all-pH efficient and durable electrocatalytic activity. Identifying Co9S8as the catalytically active phase and developing carbon-armoring as the improvement strategy are anticipated to give a fresh impetus to rational design of high-performance noble-metal-free water splitting catalysts.

In this work, tungsten oxide (WO3) with three-dimensional flower-like and wheel-like architectures, based on the spontaneous aggregation of one-dimensional nanorods, were successfully fabricated by adjusting the pH of the precursor solution. The influence of pH on the morphologies of WO3was systematically studied, and the different WO3architectures were used to photocatalytically degrade rhodamine B. The kinetic features of photoinduced charges of as-prepared WO3have been investigated by surface photovoltage spectroscopy and transient photovoltage techniques in detail. WO3with wheel-like and flower-like structures possess the higher charge separation efficiency and the lower recombination rate of photoinduced charges, resulting in higher photocatalytic activity for the degradation of RhB.

Motivated by a phenomenon in an experiment conducted in the Northwestern Pacific indicating that the energy of the received signal around the sound channel axis is much greater than that at shallower depths, we study sound propagation from the transitional area (shelfbreak) to deep water. Numerical simulations with different source depths are first performed, from which we reach the following conclusions. When the source is located near the sea surface, sound will be strongly attenuated by bottom losses in a range-independent oceanic environment, whereas it can propagate to a very long range because of the continental slope. When the source is mounted on the bottom in shallow water, acoustic energy will be trapped near the sound channel axis, and it converges more evidently than the case where the source is located near the sea surface. Then, numerical simulations with different source ranges are performed. By comparing the relative energy level in the vertical direction between the numerical simulations and the experimental data, the range of the air-gun source can be approximated.

Hybrid Pt–Co:ZnO nanostructure photocatalysts were prepared via a facile two-step synthetic strategy. SPS and TPV investigations demonstrate the existence of the synergetic effect between Pt and Co dopants. Such synergetic effect could make use of visible photons as well as facilitates the separation of photogenerated charges to prevent recombination, effectively prolongating the charges lifetime to participate photocatalytic reaction. The synergetic effect exist in Pt–Co:ZnO inducing as high as 7.7-fold in photovoltaic response and 10-fold in the photo–activity for hybrids compared to Co:ZnO.

The improvement of photoinduced charge separation is the key for light-harvesting systems in both photovoltaic and photoelectrochemical solar cells. In this study, the charge separation efficiency has been modulated through varying the magnitude of interfacial electric field in p–n Cu2O homojunction films prepared by simple electrodeposition method. The photoelectrochemical and surface photovoltage measurements were used to investigate the behaviors of photoinducded charge carriers in different p–n Cu2O homojunction films. The results confirmed that the p–n Cu2O homojunction film which exhibited the highest charge separation efficiency resulted in the highest activity in photocatalytic reduction of methyl viologen. These implied that it is possible to achieve high charge separation efficiency via constructing a large magnitude of interfacial electric field within a semiconductor using a simple electrodeposition method.

It is difficult to update the finite element (FE) model of the large-scale or complex structures such as bridges by using the regular methods since the dynamic analysis of complex structures always result in the heavy computational burden. A new updating method based on component mode synthesis (CMS) was proposed to improve the efficiency of FE model updating of large-scale structures. The effectiveness of the proposed method was validated by updating the FE model of a scaled bridge model with measured modal parameters.

To gain a flat recess profile with uniform etching depth, dry recess experiment with different inductively coupled plasma (ICP) etching conditions was done on an AlGaN/GaN heterostructure. Trenching effect at the bottom near the sidewall was observed when positive photoresist was utilized and the ICP power was low. The recess profile was improved by adopting SiO2as the etching mask and increasing the ICP power. GaN metal--oxide--semiconductor field-effect transistors (MOSFETs) on AlGaN/GaN heterostructure with different gate recess conditions were fabricated and characterized. The maximum field-effect mobility of 152.8 cm-2V-1s-1and the minimum interface state density of $1.39\times 10^{11}$ cm-2eV-1were obtained from the optimized gate recess condition with ICP power of 100 W, bias power of 20 W and etching mask of SiO2.

A series of Bi2O3/BaTiO3composite photocatalysts with different mass ratios of Bi2O3vs BaTiO3were prepared by an impregnating-annealing method. X-ray diffraction (XRD), high-resolution transmission electron microscopic (HRTEM), and UV–vis diffuse reflection spectroscopy (DRS) confirmed that Bi2O3and BaTiO3coexisted in the composites. The results of surface photovoltage (SPV) experiments showed enhancements of photovoltaic response in composites, which indicated a higher separation efficiency of photoinduced charges due to the establishment of an efficient interfacial electric field between Bi2O3and BaTiO3in the composites. The consistency of phtocatalytic activity and photovoltaic response intensity of photocatalysts showed that the efficiency interfacial electric field between Bi2O3and BaTiO3played an important role in improving the degradation efficiency of Rhodamine B (RhB). The 60%-Bi2O3/BaTiO3sample with the best activity was found by optimizing the mass ratios of Bi2O3vs. BaTiO3. On the basis of the work function (WF) measurements, a reasonable energy band diagram was proposed for BaTiO3/Bi2O3composite. It would be helpful in designing and constructing high efficiency heterogeneous semiconductor photocatalyst.

Although it has been well established that oxidative stress triggering a variety of signaling pathways leads to cell death, little attention has been paid to how these pathways affect prosurvival factors such as insulin-like growth factor-1 (IGF-1). In this study, we found that the prosurvival signaling of IGF-1 was attenuated by H2O2. To study the mechanism underlying this phenomenon, cells pretreated with Trolox or various glutamate receptor antagonists i.e. N-methyl-D-aspartate (NMDA) receptor antagonist dizocilpine maleate (MK-801), non-NMDA receptor antagonist 6,7-dinitroquinoxaline-2,3-dione (DNQX), metabolic glutamate receptor antagonists LY341495 and CPCCOEt were exposed to H2O2, and then stimulated by IGF-1. The phosphorylation statuses of IGF-1 receptors, Akt and ERK, were determined by western blotting, and cell viability was analyzed by an MTT assay. IGF-1 exerted a potent neuroprotective effect against B27 deprivation, and this effect was abolished by 100 M H2O2. Meanwhile, the phosphorylation of IGF-1 receptors, Akt and ERK, was attenuated. Moreover, the phosphorylation of Akt was more susceptible to H2O2insult than IGF-1 receptors. MK-801 increased the phosphorylation of IGF-1 receptors and its downstream target Akt, and thereby promoted cell survival, whereas the other glutamate receptor antagonists exerted no effect. Antioxidant Trolox did not restore IGF-1 signaling, but it increased Akt phosphorylation and also increased cell viability. These results showed that H2O2impaired IGF-1 prosurvival signaling through two pathways. One pathway disrupted the autophosphorylation of IGF-1 receptors through NMDA receptors and the other directly dephosphorylated Akt.

The effects of low temperature electronic cyclotron resonance microwave hydrogen plasma pretreatment and post-annealing on the electrical properties of Ti and Ni contacts to 4H-SiC were investigated. The HPT improves the Ohmic behavior of Ti/4H-SiC contact significantly. In contrast, it remarkably enhances the rectifying behavior of Ni/4H-SiC contact. The properties of Ti Ohmic contact and Ni rectifying contact improve with increasing annealing temperature up to 400 °C. However, they are deteriorated above 400 °C. X-ray photoelectron spectroscopy measurements confirm that the surface Fermi level ($E_{\text{F}}^{\text{s}}$) moves toward the conduction band edge by the HPT. It almost attains the bulk Femi level position after annealing at 400 °C with the surface states density ($D_{\text{s}}$) as low as $4.43\times 10^{11}$ cm-2eV-1. However, after annealing above 400 °C, $E_{\text{F}}^{\text{s}}$ moves back closer to midgap with an increase of $D_{\text{s}}$. The experimental results are found to obey the barrier height theory of Cowley and Sze.

Abstract: By using the surface photovoltage (SPV) technique based on a lock-in amplifier, surface states located 3.1 eV below the conduction band of TiO2 have been detected in TiO2 nanotube arrays prepared by anodization of titanium foil in fluoride-based ethylene glycol solution. The photo-induced charge transportation behavior of TiO2 nanotube arrays was also studied by qualitatively analyzing their SPV phase spectra measured under different external bias. When a negative bias was applied, carriers excited from surface states have the same transportation properties as those excited from the valence band; in contrast, when a positive bias was applied, these two kinds of photo-excited carriers exhibit different transportation behavior.

A series of different crystalline phases BiVO4photocatalysts (tetragonal, monoclinic, and monoclinic/tetragonal heterophase) have been prepared by a coprecipitation and molten salt method. High-resolution transmission electron microscopy (HRTEM) results show that an interface of intimate contact is formed in monoclinic/tetragonal heterophase and monoclinic phase is mainly on the surface of nanoparticles. Surface photovoltage (SPV) and transient photovoltage (TPV) techniques are used to further investigate the transfer process of photoinduced charge carriers. The results show that the behavior of photoinduced charges markedly depend on the crystalline phases of BiVO4samples, and the presence of interface in monoclinic/tetragonal heterophase provides a spatial condition for charge transfer, promotes the separation of photoinduced electron–hole pairs, and changes the migration direction of photoinduced carriers. The relationship between behavior of photoinduced charge carriers and photocatalytic activity was discussed in detail, which would provide a greater insight into the intrinsic reasons of the enhancement in photocatalytic activity.

In this work, Fe-doped flowerlike ZnO powders with various doping contents were successfully fabricated by a hydrothermal method. The results of X-ray diffraction and UV–vis DRS spectra revealed that the Fe ions have been successfully doped into the crystal lattice of the ZnO host structure, and the optical absorption response of Fe-doped ZnO was extended into the visible region for the incorporation of Fe ions. The room-temperature photoelectric gas sensing of formaldehyde (HCHO) based on the Fe-doped ZnO was also studied under 532 nm light irradiation provided by a green laser pointer. It was found that the as-prepared Fe-doped ZnO samples showed excellent sensitivity, in which the gas response to 5 and 100 ppm formaldehyde can reach to 22% and 287% under 532 nm light irradiation at room temperature, respectively. The sensing mechanism of the obvious visible-light-induced photoelectric gas sensing was discussed with the help of surface photovoltage measurement. Our results demonstrated that visible light irradiation was a promising approach to achieving a large response for gas sensors at room temperature. This work will pave a way for the development of a low-cost practical gas sensor.

Mesoporous TiO2(meso‐TiO2) is a promising photoelectrical nanomaterial for high dye‐sensitised solar cell (DSSC) performance, because its nanochannels offer a large internal surface area to allow for more dye adsorption. The interconnected grains facilitate rapid electron transport both within the meso‐TiO2film and at the film electrode dye/redox shuttle electrolyte interfaces. In this work, a series of DSSCs has been fabricated on the basis of meso‐TiO2with large controllable pore sizes (6.5, 8.2 and 11.0 nm). It was found that the DSSC with the 8.2 nm meso‐TiO2photoelectrode has the highest photoelectrical conversion efficiency, which is higher than that of the conventional P25 nanoparticulate DSSC under the same conditions. The measurements of the N2sorption isotherms and the photovoltage transient demonstrates that such improved efficiency can be ascribed to the larger surface area and the fastest interfacial charge transfer. Meanwhile, the effect of different pore sizes on the photoelectrical conversion efficiency has been systematically investigated, and a possible model for the efficient electrolyte percolation in the dye‐sensitised mesoporous photoelectrode has been proposed.

Bi2WO6/ZnWO4composite photocatalysts have been successfully synthesized by a facile hydrothermal process. The catalysts were characterized by powder X-ray diffraction (XRD), transmission electron microcopy (TEM), and UV–vis diffuse reflectance spectrum (DRS). The results show that Bi2WO6nanoparticles grow on the primary ZnWO4nanorods. The Bi2WO6/ZnWO4composites have better UV light photocatalytic activities compared to single ZnWO4nanorods. Furthermore, the photoinduced charge transfer properties of Bi2WO6/ZnWO4composites were investigated by means of transient photovoltage (TPV) technique in detail. The interconnected interface of Bi2WO6/ZnWO4composites led to the low recombination ratios of photoinduced electron–hole pairs and enhanced photocatalytic activities.

CdS nanowire/ZnO nanosphere materials (CdS/ZnO) with hierarchical structure were synthesized by a three-step solvothermal process. XRD, FESEM and TEM analysis confirmed the growth of ZnO nanospheres on the surface of CdS nanowires (NWs). The transient photovoltage (TPV) measurements revealed that the interface between CdS and ZnO can inhibit the recombination of photogenerated excess carriers and prolong the lifetime of excess carriers in CdS/ZnO materials. Moreover, the CdS/ZnO materials exhibit a dramatic improvement in optoelectronic performance and visible-light-irradiation gas sensing activity, which gave 1 order of magnitude larger than that of CdS NWs in response to formaldehyde. The enhancement of sensing properties is attributed to the interfacial transport of excess carriers.

The behavior of photogenerated charges in the Fe3O4@Fe2O3core/shell nanoparticles with high photocatalytic activity have been investigated by surface photovoltage (SPV) spectroscopy and transient photovoltage (TPV) measurements. The single-phase Fe3O4and Fe2O3particles as references have been investigated simultaneously. The results demonstrate that the junction formation in the Fe3O4@Fe2O3nanoparticles significantly affects the separation, transport, and recombination of photogenerated charges and even changes the transport direction and recombination velocity. And the mechanisms here have been discussed in detail. These results are helpful in understanding the photoelectric process of nanoscaled materials with the heterojunction structures and further utilizing the photoelectric materials and devices.

Near‐monodisperse Bi‐doped anatase TiO2nanospheres with almost uniform diameters in the range of 117 to 87 nm were prepared simply by introducing different amounts of bismuth nitrate pentahydrate into the reaction system and subsequent calcinations. X‐ray diffraction, UV‐visible diffuse reflectance spectra, and X‐ray photoelectron spectroscopy confirm that the doped ions substitute some of the lattice titanium atoms, and furthermore, Bi3+and Bi4+ions coexist. All the Bi‐doped TiO2samples show much better photocatalytic activity than pure TiO2in the degradation of rhodamine B (RhB) under the irradiation of visible light (λ>420 nm), and, interestingly, it was found that the degradation mechanism is different from the conventional one, which has already been reported elsewhere. The detailed mechanism is discussed in this article.

BiOI/TiO2heterostructures with different Bi to Ti molar ratios were synthesized through a simple soft-chemical method at a temperature as low as 80 °C. The as-prepared powders were characterized by X-ray powder diffraction, electron microscopy, UV−vis diffuse reflectance spectroscopy, nitrogen sorption, and X-ray photoelectron spectroscopy. The photocatalytic activities of these BiOI/TiO2heterostructures were evaluated on the degradation of methyl orange under visible-light irradiation (λ > 420 nm). The results revealed that the BiOI/TiO2heterostructures exhibited much higher photocatalytic activities than pure BiOI and TiO2, respectively, and 50%BiOI/TiO2showed the best activity among all these heterostructured photocatalysts. Surface photovoltage spectroscopy and transient photovoltage measurements were used to confirm the formation of heterojunction and probe charge transfer between BiOI and TiO2. The visible-light photocatalytic activity enhancement of BiOI/TiO2heterostructures could be attributed to its strong absorption in the visible region and low recombination rate of the electron−hole pairs because of the heterojunction formed between BiOI and TiO2.

High-crystallinity anatase TiO2nanocrystals with the size of ∼2−4 nm have been prepared by a facile and quick method at low temperature. Ethylene glycol was used to both control the hydrolysis and condensation rates of titanium isopropoxide. H2O used in this reaction system, is the key reagent for the anatase formation, and the amount of H2O has been demonstrated to be an important parameter for the fast anatase phase formation. The plausible reaction mechanism has been discussed on the basis of the results of SEM, TEM, HRTEM, XRD, UV−vis, FT-IR, and TGA measurements. By studying the sensing properties of the as-synthesized anatase nanocrystals, it has been found that the nanocrystals exhibit the fast response to oxygen under the UV illumination at room temperature.

An ASM-based high level semantical model for service-oriented systems based on OSGi and supporting service dynamic updating is provided in this paper. The model not only provides the refinement methods but also gives the final model that specifies the constraint of OSGi. The resulting formal model can be applied in several ways. First, it enables checking or comparing existing systems based on OSGi to determine if they satisfy the dynamic updating demands and provide the necessary functionalities. Furthermore, it can serve as a basis for high level specification of a new system or components or updating constraint. Finally, the model is also useful in reasoning about the properties of service-oriented dynamic updating system based on OSGi.

TiO2-based dye-sensitized solar cells doped with different sizes of ZnO nanorods were fabricated and studied by photoelectrochemical measurements. The results show that the solar conversion efficiency of the dye-sensitized solar cells after the addition of ZnO nanorods (1 wt %) was increased by about 15% compared to that without ZnO nanorods. The effect of different sizes of ZnO nanorods on the charge carrier transport properties has been studied in the composite semiconductor film by means of a transient photovoltage technique. The result indicates that the carrier diffuse rate in the cis-di(isothiocyanato)-bis(4,4‘-dicarboxy-2,2‘-bipyridine)ruthenium(II)-sensitized TiO2/ZnO film electrode was about 1 to 3 orders of magnitude faster than that in the TiO2electrode. The cyclic voltammograms suggest that the conduction band edge shifts toward the vacuum level after the addition of ZnO nanorods in working electrodes, which may be the main cause of the enhancement of the open-circuit photovoltage (Voc). The experimental results indicate that the addition of ZnO nanorods can improve charge carrier transport, decrease recombination, enhance Voc, and increase the efficiency of energy conversion.

ZnO nanorod arrays on an ITO substrate and nanorod powder have been prepared via a chemical method in aqueous solution at low temperature. Two dimensions of composite nanorods in the arrays were obtained by controlling the reaction time. SEM, XRD, UV−vis transmission, and PL measurements have been utilized to characterize the samples. The surface photovoltage (SPV) spectra of the three samples have been comparatively investigated by a lock-in amplifier with dc bias and Kelvin probe (KP) based measurements. The kinetic features of SPV responses are interpreted in terms of ac SPV phase spectra and SPV transients on a KP. We demonstrate that the photovoltaic properties of ZnO nanorods not only depend on the rod size, but also rely on the crystallographic orientation. The mechanisms therein have been discussed in detail. Our results could lead to better understanding of the photovoltaic properties in ZnO nanostructures.

Summary:We demonstrate in this communication that large‐scale coaxial nanocables of polypyrrole (PPy)/TiO2can be obtained via three steps: (1) synthesis of TiO2nanofibers by electrospinning; (2) physical adsorption Fe3+oxidant on the surface of TiO2nanofibers; (3) followed by polymerization of pyrrole (from vapor) on the surface of TiO2nanofibers. During the synthesis, the PPy formed on TiO2nanofibers as a template and formed PPy/TiO2coaxial nanocables. TEM image proved that PPy (20 nm thickness) covered the surface of TiO2nanofibers. Fourier‐transform infrared (FTIR), X‐ray photoelectron spectra (XPS), and X‐ray diffraction patterns (XRD) characterized the chemical structure of the coaxial nanocables. Surface photovoltage spectroscopy (SPS) revealed the surface properties of the PPy/TiO2coaxial nanocables.

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In this study, a new polyorganophosphazene with pendant carbazolyl groups was synthesized, and its structure was characterized by IR, ¹H-NMR, and ³¹P-NMR spectroscopy. To understand its carrier photogeneration and transport property, we also studied fluorescence spectra and photovoltage spectra. Fluorescence spectra show that the polymer possesses properties dissimilar to those of PVK. There are only two emission peaks at ≈ 360 nm in its spectra, which coincides with that of the monomer model compound, 9-ethylcarbazole. This may be because of the influence of the spacer. The results of SPS shows that band–band transition mainly comes from electron π–π* transition, and the polymer is a p-type semiconductor. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1446–1451, 2001