Search

Immiscible liquids are commonly used to achieve unique functions in many applications, where the breakup of compound droplets in airflow is an important process. Due to the existence of the liquid-liquid interface, compound droplets are expected to form different deformation and breakup morphologies compared with single-component droplets. We investigate experimentally the deformation and breakup of compound droplets in airflow. The deformation characteristics of compound droplets are quantitatively analyzed and compared with single-component droplets. Theoretical models are proposed to analyze the transition between breakup morphologies. The breakup modes of compound droplets are classified into shell retraction, shell breakup, and core-shell breakup based on the location where the breakup occurs. The comparison with single-component droplets reveals that the compound droplet is stretched more in the flow direction and expands less in the cross-flow direction, and these differences occur when the core of the compound droplet protrudes into the airflow. The transition conditions between different breakup modes are obtained theoretically. In addition, the eccentricity of the compound droplet can lead to the formation of the thick ligament or the two stamens in the droplet middle. [ABSTRACT FROM AUTHOR]

The breakup of non-Newtonian droplets is ubiquitous in numerous applications. Although the non-Newtonian property can significantly change the droplet breakup process, most previous studies consider Newtonian droplets, and the effects of non-Newtonian properties on the breakup process are still unclear. This study focuses on the secondary breakup of shear-thinning droplets by numerical simulation. The volume of fluid method is used to capture interface dynamics on adaptive grids. To compare shear-thinning droplets and Newtonian droplets, a new definition of the Ohnesorge number is proposed by considering the characteristic shear rate in the droplet induced by the airflow. The results show that compared with the Newtonian fluid, the shear-thinning properties can change the apparent viscosity distribution inside the droplet, alter the local deformation, change the droplet morphology, and affect the transition in the droplet breakup regime. [ABSTRACT FROM AUTHOR]

To study the eccentric compression performance and failure mechanism of ultra-high performance concrete (UHPC) encased concrete-filled steel tubular (CFST) medium-long columns (UC-CFST medium-long columns), a total of 27 UC-CFST column specimens were tested under eccentric compression with eccentricity and slenderness ratio as the main parameters. After verified by experimental results, the finite element (FE) analysis of UC-CFST medium-long columns with actual structural cross-sectional size under eccentric compression was further carried out. It is found that as the slenderness ratio and eccentricity increased, the bending stiffness and the ultimate bearing capacity of the UC-CFST columns decreased gradually, and the failure mode changed from strength failure to instability failure, and the smaller the proportion of encasing UHPC area, the greater the upper-bound slenderness ratio of strength failure. Moreover, the influence of eccentricity was nonlinearly coupled with slenderness ratio on the eccentric compressive bearing capacity of UC-CFST medium-long columns. Finally, a calculation method of ultimate load-bearing capacity of UC-CFST medium-long columns considering the influence of eccentricity and slenderness ratio was proposed, which had good calculation accuracy with experimental and numerical results. • Eccentric compression tests were conducted on UHPC-encased CFST columns with varying eccentricities and slenderness ratios. • Failure modes and bearing capacity of UHPC-encased CFST medium-long columns under different eccentric loads were discussed. • The limit slenderness ratio of UHPC-encased CFST eccentrically loaded column when instability occurs was determined. • The influence of eccentricity was coupled with slenderness ratio on the ultimate bearing capacity of UC-CFST columns. • A simplified calculation method for the ultimate bearing capacity of UHPC-encased CFST medium-long columns was proposed. [ABSTRACT FROM AUTHOR]

Rational design and controllable synthesis of metal-organic frameworks nanosheets is critical for electrochemical catalysis. Herein, a carnation-like ZIF-9 nanostructure made of nanosheets is grown on nickel foam (ZIF-9/NF) by a simple one-step solvothermal method, the morphology evolution and the electrocatalytic oxygen evolution properties have been investigated by controlling the solvothermal time. The binder-free ZIF-9-d/NF (60 h, solvothermal time is 60 h) electrode delivers efficient electrocatalytic oxygen evolution reaction activity with low overpotentials of 312 and 337 mV at 50 and 100 mA cmâˆ'2, respectively. Furthermore, ZIF-9-d/NF (60 h) exhibits excellent stability without obvious attenuation for at least 30 h at 200 mA cmâˆ'2. The excellent performances can be attributed to the combination of the highly exposed active sites in the ZIF-9-d nanosheets, as well as the effective electron conduction and mass transfer. This work provides much possibilities for ZIF-9 nanosheets as binder-free electrode for electrocatalyst. [ABSTRACT FROM AUTHOR]

2D bimetal metal organic frameworks (MOFs) are recognized as one of the most promising electrocatalysts for the oxygen evolution reaction (OER). Herein, a facile approach was proposed to construct NiFe-MOF nanosheets on Fe foam (FF). As a self-supporting electrode, the NiFe-MOF/FF electrode shows impressive electrocatalytic OER performance. Specifically, it exhibits an ultra-low overpotential of 216 mV to reach a current density of 50 mA cm−2, and outstanding stability (beyond 50 h at 200 mA cm−2). The excellent performances of NiFe-MOF/FF arise from the highly exposed active centers, the excellent conductivity, and the synergy effect between Ni and Fe. This research provides a promising strategy for the synthesis of multi-metal MOFs as high-efficiency electrocatalysts. [ABSTRACT FROM AUTHOR]

The deformation and breakup of droplets in airflows is important in many applications of spray and atomization processes. However, the shear effect of airflow has never been reported. In this study, the deformation and breakup of droplets in the shear flow of air is investigated experimentally using high-speed imaging, digital image processing, and particle image velocimetry. We identify a new breakup mode of droplets, i.e., the butterfly breakup, in which the strong aerodynamic pressure on the lower part of the droplet leads to the deflection of the droplet and then the formation of a butterfly-shaped bag. A regime map of the droplet breakup is produced, and the transitions between different modes are obtained based on scaling analysis. The elongation and the fragmentation of the droplet rim are analyzed, and the results show that they are significantly affected by the shear via the formation and the growth of nodes on the rim. [ABSTRACT FROM AUTHOR]

Abstract: A nanocomposite Graphene/Neutral Red (GNR) was fabricated via a facile electrochemical method by reducing graphene oxide (GO) and covalent bonding with NR on glassy carbon electrode (GCE) in one step. The bond between NR and graphene was characterized and demonstrated by X‐Ray Diffraction (XRD), X‐ray Photoelectron Spectroscopy (XPS), UV‐vis, Fourier Transform Infrared (FT‐IR). Electrochemical data revealed that the GNR resulted in a sensitivity enhancement of uric acid (UA) oxidation and CV curve shown that the catalytic oxidation current is linearly dependent on UA concentration in the range of 0.5–50 μM and 50 μM−2 mM with a detection limit of 0.076 μM (S/N=3). The existing ions and physiological interferents were tested and they were nearly negligible or have a very small influence. Moreover, 2 weeks stability was obtained. By compared with other UA sensor, the present method is simple than previous report and the performance is better. [ABSTRACT FROM AUTHOR]

BiOCl nanosheet (NSs) with exposed (010) facets have been successfully synthesized via a facile diffusion process at water-air interface at room temperature. The X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) results confirm the formation of octagonal BiOCl NSs with exposed (010) facets. BiOCl photocatalyst with exposed (010) facets exhibits higher photocatalytic activity than BiOCl photocatalyst with exposed (001) facets under UV light irradiation. This novel photocatalyst demonstrates potential application for organic pollutant elimination and proposes insights for designing highly efficient BiOCl based photocatalysts. [ABSTRACT FROM AUTHOR]

Droplet breakup is important in many natural and industrial processes, but the current classification of breakup regimes, especially the intermediate breakup regime, is ambiguous. In this study, the transitions of breakup regimes for viscous droplets are investigated experimentally using high-speed imaging taken from a side view and a 45° view. Based on the morphology change in the middle of the droplet, the breakup regimes are classified into no-breakup, bag breakup, bag-stamen, low-order multimode, high-order multimode, and shear-stripping breakup. The droplet morphologies in different regimes and the corresponding transitions are discussed in detail. The droplet viscosity dissipates the kinetic energy transferred by the airflow during the initial droplet flattening, and affects the development of the Rayleigh–Taylor instability wave after the flattening. Through the analysis of the droplet deformation and the Rayleigh–Taylor instability with the droplet viscosity taken into account, the transition conditions of different regimes are obtained in a regime map. By further considering the relative velocity loss between the droplet and the airflow, the ranges of the dual-bag breakup in the low-order multimode regime and the droplet retraction in the bag-stamen regime are determined. [Display omitted] • Breakup of viscous droplets in airflow is investigated experimentally. • Various morphologies and the corresponding transitions are discussed. • Multimode breakup is classified into low-order and high-order regimes. • Transition conditions for each regime are obtained theoretically. [ABSTRACT FROM AUTHOR]

An ultraviolet (UV)-durable super-hydrophobic ZnO/Ni lotus-like nanostructure was fabricated via a simple two-step electrodeposition method at low temperature. The as-prepared ZnO/Ni nanostructure showed excellent UV-durable super-hydrophobicity and water ultra repellency. The Ni nanoclusters with different density could be successfully fabricated on the surface of ZnO NR by modulating the electrodeposition time of Ni nanoclusters, which affected surface roughness and wettability. The triple-level roughness resulted from high density Ni nanoclusters played a important role in the super-hydrophobicity of ZnO/Ni nanostructure. This super-hydrophobic surface showed high stability in water for long term. Furthermore, the layer of Ni nanoclusters avoided the photoinduced wettability conversion of ZnO and hence greatly improved the UV-durability of this super-hydrophobic surface, which were essential elements for practical applications. This simple method could be applied to various substrates, such as metal surfaces and other electric conductive substrates. [ABSTRACT FROM AUTHOR]

Transition bimetallic sulphides have emerged as important electrode materials for supercapacitors owing to their low toxicity, environmental friendliness, cost-effectiveness, multiple oxidation states, high natural abundance, flexible structure, and high theoretical specific capacitance. Herein, a porous nanosheet–nanosphere@nanosheet FeNi2-LDH@FeNi2S4 (FNLDH@FNS) core–shell heterostructure was directly prepared on nickel foam (NF) via a two-step hydrothermal method. The prepared electrode material exhibits an outstanding electrochemical performance. The specific capacity (Cs) values are 806 and 450 C g−1 at current density (Dc) values of 1 and 6 A g−1, respectively, revealing a satisfactory magnification performance. In addition, the FNLDH@FNS electrode exhibits a long cycle life with an supercapacitor (SC) retention rate of 92.3% after 5000 cycles at a Dc of 6 A g−1. The FNLDH@FNS//activated carbon (AC) asymmetric SC assembled with FNLDH@FNS (positive electrode) and activated carbon (AC, negative electrode) displays an energy density (Ed) of 36.67 Wh kg−1 and a power density (Pd) of 775.17 W kg−1. [ABSTRACT FROM AUTHOR]

Homing peptides are exploited in nanomedicine to functionalize either free drugs or nanostructured materials used as drug carriers. However, the influence of multivalent versus monovalent peptide presentation on the interaction with the receptor and on the consequent intracellular delivery of the associated cargo remains poorly explored. By using a tumor-homing peptide (T22) with regulatable self-assembling properties we have investigated here if its display in a either a monomeric form or as multimeric, self-assembled protein nanoparticles might determine the efficacy of receptor-mediated penetrability into target cells. This has been monitored by using a fluorescent cargo protein (iRFP), which when fused to the homing peptide acts as convenient reporter. The results indicate that the nanoparticulate protein versions are significantly more efficient in mediating receptor-dependent uptake than their unassembled counterparts. These finding stresses an additional benefit of nanostructured materials based on repetitive building blocks, regarding the multivalent presentation of cell ligands that facilitate cell penetration in drug delivery applications . [ABSTRACT FROM AUTHOR]

Energy efficiency (EE) has become an important design goal for mobile communication systems. Since the EE of a system is evaluated during a period of time, a transmission strategy designed from maximizing instantaneous EE (INEE) may not achieve the maximal EE of the system. To exploit the accumulative nature of the energy, accumulative EE (ACEE) can be used as the objective function, which is the ratio of the accumulated amount of data transmitted to the accumulated energy consumed until the time for optimization. In this paper, we study when ACEE is beneficial to EE-oriented optimization. By taking a single user multi-antenna multi-subcarrier system serving two classes of traffic as an example, we formulate three problems to optimize rate allocation among subcarriers and time slots respectively maximizing the INEE, ACEE and EE upper-bound, which can be easily extended to multi-user systems. We proceed to analyze the behavior and performance of the corresponding solutions. Analytical and simulation results show that using ACEE yields a more energy efficient design for the systems serving best effort traffic with less transmit antennas, serving less users simultaneously or at low signal to noise ratio under time-varying channels. However, the conclusions for real-time traffic are different. [ABSTRACT FROM PUBLISHER]

Heterogeneous networks (HetNets) consisting of macro- and pico-cells can well tackle the contradictory requirements on large coverage of the network and high data rate at the hot spots. In this paper, we study energy-efficient precoding for coordinated multi-point (CoMP) transmission for HetNets. We formulate a problem that maximizes the energy efficiency under the constraints of individual date rate requirement from each user, maximal transmit power of each base station (BS), and zero-forcing (ZF) for a HetNet where the macro-BS cooperates with multiple pico-BSs. We then simplify the problem with the help of the practical topology of HetNets where the macro-BS cooperates with each of the pico-BSs. By introducing the subspace decomposition method and exploiting the feature of HetNets, we obtain the structure of the optimal ZF CoMP precoder. To reduce the computational complexity and hence the circuit power consumed for signal processing, we propose a suboptimal ZF precoder with closed-form expression for the HetNets with isolated pico-cells. We demonstrate the performance of the proposed ZF precoders by comparing with several existing optimal linear precoders. [ABSTRACT FROM PUBLISHER]

In this paper, we investigate adaptive configuration of spatial and frequency resources to maximize energy efficiency (EE) and reveal the relationship between the EE and the spectral efficiency (SE) in downlink multiple-input-multiple-output (MIMO) orthogonal frequency division multiple access (OFDMA) systems. We formulate the problem as minimizing the total power consumed at the base station under constraints on the ergodic capacities from multiple users, the total number of subcarriers, and the number of radio frequency (RF) chains. A three-step searching algorithm is developed to solve this problem. We then analyze the impact of spatial-frequency resources, overall SE requirement and user fairness on the SE-EE relationship. Analytical and simulation results show that increasing frequency resource is more efficient than increasing spatial resource to improve the SE-EE relationship as a whole. The EE increases with the SE when the frequency resource is not constrained to the maximum value, otherwise a tradeoff between the SE and the EE exists. Sacrificing the fairness among users in terms of ergodic capacities can enhance the SE-EE relationship. In general, the adaptive configuration of spatial and frequency resources outperforms the adaptive configuration of only spatial or frequency resource. [ABSTRACT FROM PUBLISHER]

A new two-dimensional {Cu6}-added polyoxometalate cluster–organic framework (Cu-POMCOF) was prepared by a hydrothermal method from lacunary polyoxoanions and was applied as a solid support for immobilizing MP-11 and Cyt c. The biocomposite complex exhibits higher stability and catalytic activity than the original free enzyme. [ABSTRACT FROM AUTHOR]

In this paper, power allocation between pilots and data symbols is investigated to maximize energy efficiency (EE) for downlink orthogonal frequency division multiple access (OFDMA) networks. We first derive an EE function considering channel estimation error, which depends on large-scale channel gains of multiple users, allocated power to pilots and data symbols, and circuit power consumption. Then an optimization problem is formulated to maximize the EE under overall transmit power constraint. Exploiting the quasiconcavity property of the EE function, we propose an alternating optimization method in the low transmit power region and reformulate a joint quasiconcave problem in the high transmit power region. Analysis and simulation results show that the power ratio for pilots decreases with the circuit power. When the circuit power is small, the optimal overall transmit power increases with the circuit power. Otherwise, the optimal transmit power does not depend on it. Transmitting more data symbols to the users with higher channel gains improves the EE but at a cost of sacrificing the fairness among multiple users. Simulation results also demonstrate that compared with spectral efficiency (SE)-oriented design, the EE-oriented design can improve the EE performance significantly with a relatively small SE loss. [ABSTRACT FROM PUBLISHER]

It is important to develop highly efficient and durable Earth-abundant oxygen evolution reaction (OER) electrocatalysts by an energy- and time-saving strategy. Herein, a facile strategy was used to synthesize S-doped nickel–iron oxyhydroxide (S–Ni/FeOOH) nanoparticles on nickel–iron foam (NFF) (S–Ni/FeOOH@NFF), which exhibits a striking enhancement of OER performance compared to Ni/FeOOH@NFF. The free-standing S–Ni/FeOOH@NFF electrode possesses a low overpotential of 229 mV at a current density of 10 mA cm−2, which is 180 mV lower than that of Ni/FeOOH@NFF. In addition, the electrode was also remarkably stable. The current density still remains at 95% after 150 h at a high current density of 100 mA cm−2. [ABSTRACT FROM AUTHOR]

Constructing a heterostructure is an efficient strategy to enhance the catalytic activity toward the oxygen evolution reaction (OER). Herein, Ce-modified Ni(OH)2 nanoparticles are anchored on Ni-MOF nanosheets by the electrodeposition strategy, forming a self-supporting electrode of Ce-m-Ni(OH)2@Ni-MOF. The Raman spectrum proves that both Ce(OH)3 and Ce doping exist in Ce-modified Ni(OH)2 nanoparticles. The heterostructure possesses an open nanosheet structure, with a good interaction between Ni-MOF and Ce-m-Ni(OH)2, which enables efficient mass/charge transfer and the synergetic effect between Ni and Ce, leading to a high-performance electrocatalyst. Specifically, Ce-m-Ni(OH)2@Ni-MOF achieves current densities of 50 and 100 mA cm−2 at low overpotentials of 219 and 272 mV, respectively, and retains high activity for at least 30 h. [ABSTRACT FROM AUTHOR]

• A method is proposed to measure the transient concentration field of vapor. • The method is based on modified background oriented Schlieren and image processing. • Evolution of vapor concentration during impact of volatile droplets is obtained. • The vapor distribution differs from diffusion-limited model because of convection. • The complex structure of vapor cloud is due to interplay among different factors. The direct visualization of vapor distribution and quantitative measurement of vapor concentration plays an important role in studying droplet evaporation. In this study, we propose a method to measure the vapor concentration field based on the modified background oriented Schlieren, inverse Radon transform, high-speed imaging, and image processing. The method is demonstrated for the measurement of the transient concentration field during the impact of volatile droplets on solid surfaces. The results show that the vapor distribution is remarkably different from the diffusion-limited model because of the strong convection. The complex structure of the vapor cloud is the result of the interplay among fluid inertia, fluid evaporation, vapor diffusion, vapor convection, and droplet shape evolution. [ABSTRACT FROM AUTHOR]

A novel and facile method is developed to prepare an Ag@AgCl film which exhibits high photocatalytic activity under visible light irradiation. In addition, it can also be used to fabricate a photodetector that possesses a fast response time and good photocurrent reproducibility. [ABSTRACT FROM AUTHOR]

Planting rice is one of the effective ways to improve saline soils, but the underlying mechanisms are unknown. We studied basic soil properties (including pH, salt content, total nitrogen, etc.) and microbial diversity of the bare soil (salt content >4 g/kg, CK), the Suaeda (Suaeda glauca (Bunge) Bunge) soil (JP), and the soil in which rice (cv. Huaidao 5) grew for one (1Y) and three (3Y) years. The results showed that the soil salinity decreased in the order: CK > JP > 1Y > 3Y. The contents of soil organic matter, total nitrogen, dissolved organic carbon, readily oxidizable carbon, microbial biomass carbon, and particulate organic carbon were higher in 1Y and 3Y compared with CK. The Chao 1 index of soil microbiome diversity was about 1.20 times and 1.49 times higher in the soils after rice compared with JP and CK, respectively. Among the soil microorganisms, the top four abundant phyla were Proteobacteria, Chloroflexi, Bacteriodetes, and Firmicutes. In summary, planting rice decreased soil salinity, and increased the content of nutrients and diversity of microorganisms, thereby improving the saline soil. Unlabelled Image • Planting rice decreased soil salinity, increased the content of nutrients • Planting rice increased diversity of microorganisms. • The contents of SOM, TN, DOC, ROC, MBC, and POC were higher for planting rice. • Planting rice is one of the effective ways to improve saline-alkali soils. [ABSTRACT FROM AUTHOR]

People's increasing demand for fossil fuels not only leads to environmental pollution but also highlights their non-renewable nature. Therefore, the urgency of developing renewable energy sources is evident. Tree branches and leaves undergo cycles of growth and decay with the changing seasons, showcasing their renewable potential. Despite this, they remain underutilized as new energy materials, particularly in the realm of high-energy-density lithium batteries. While this paper did not directly explore the utilization of various branches and leaves as raw materials for lithium–sulfur battery (LSB) cathodes, it revealed promising findings: they not only demonstrate good battery capacity but also boast considerable cycle life. The carbonized material from the leaves of Acer buergerianum can be used as the electrode of LSBs and could achieve 318.8 mA h g−1 at 4C and a decay rate of only 0.03% at 1C for 400 cycles., respectively. Therefore, the innovative method of turning decaying leaves into energy contributes significantly to the future of renewable energy and environmental protection. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) metal–organic frameworks (MOFs) with highly exposed electro-active surface are regarded as promising oxygen evolution reaction (OER) electrocatalysts. This work demonstrates the in situ conversion of NiCo-LDH (LDH: double-layer hydroxide) into an Fe-doped NiCo-MOF on a conductive substrate (Fe-NiCo-MOF/NF) by a two-step hydrothermal method. The hierarchical book-like structure of the Fe-NiCo-MOF/NF electrode provides a large electro-active surface and improved electron transport capability, leading to enhanced oxygen evolution performance in an alkaline environment. Specifically, Fe-NiCo-MOF/NF needs an overpotential of 290 mV to drive a current density of 50 mA cm−2, which is 136 mV lower than that of the precursor NiCo-LDH. Additionally, its activity can be maintained for at least 20 h at a high current density of 200 mA cm−2. Moreover, the real active centers of the catalyst were discovered to be the metal oxides converted during the OER cycles. This work used a simple hydrothermal method to enhance the OER performance, which is convenient for direct application of MOF materials in electrocatalysis fields. [ABSTRACT FROM AUTHOR]

The efficiency of photocatalytic hydrogen evolution is currently limited by poor light adsorption, rapid recombination of photogenerated carriers, and ineffective surface reaction rate. Although heterojunctions with innovative morphologies and structures can strengthen built‐in electric fields and maximize the separation of photogenerated charges. However, how to rational design of novel multidimensional structures to simultaneously improve the above three bottleneck problems is still a research imperative. Herein, a unique Cu2O─S@graphene oxide (GO)@Zn0.67Cd0.33S Three dimensional (3D) hollow heterostructure is designed and synthesized, which greatly extends the carrier lifetime and effectively promotes the separation of photogenerated charges. The H2 production rate reached 48.5 mmol g−1 h−1 under visible light after loading Ni2+ on the heterojunction surface, which is 97 times higher than that of pure Zn0.67Cd0.33S nanospheres. Furthermore, the H2 production rate can reach 77.3 mmol g−1 h−1 without cooling, verifying the effectiveness of the photothermal effect. Meanwhile, in situ characterization and density flooding theory calculations reveal the efficient charge transfer at the p‐n 3D hollow heterojunction interface. This study not only reveals the detailed mechanism of photocatalytic hydrogen evolution in depth but also rationalizes the construction of superior 3D hollow heterojunctions, thus providing a universal strategy for the materials‐by‐design of high‐performance heterojunctions. [ABSTRACT FROM AUTHOR]

Objective of this study was to utilize LASSO regression (Least Absolute Shrinkage and Selection Operator Regression) to identify key variables in septic patients and develop a predictive model for intensive care unit (ICU) mortality. Methods: We conducted a cohort consisting of septic patients admitted to the ICU between December 2016 and July 2019. The disease severity and laboratory index were analyzed using LASSO regression. The selected variables were then used to develop a model for predicting ICU mortality. AUCs of ROCs were applied to assess the prediction model, and the accuracy, sensitivity and specificity were calculated. Calibration were also used to assess the actual and predicted values of the predictive model. Results: A total of 1733 septic patients were included, among of whom 382 (22%) died during ICU stay. Ten variables, namely mechanical ventilation (MV) requirement, hemofiltration (HF) requirement, norepinephrine (NE) requirement, septicemia, multiple drug-resistance infection (MDR), thrombocytopenia, hematocrit, red-cell deviation width coefficient of variation (RDW-CV), C-reactive protein (CRP), and antithrombin (AT) III, showed the strongest association with sepsis-related mortality according to LASSO regression. When these variables were combined into a predictive model, the area under the curve (AUC) was found to be 0.801. The AUC of the validation group was 0.791. The specificity of the model was as high as 0.953. Within the probability range of 0.25 to 0.90, the predictive performance of the model surpassed that of individual predictors within the cohort. Conclusion: Our findings suggest that a predictive model incorporating the variables of MV requirement, HF requirement, NE requirement, septicemia, MDR, thrombocytopenia, HCT, RDW-CV, CRP, and AT III exhibiting an 80% likelihood of predicting ICU mortality in sepsis and demonstrates high accuracy. [ABSTRACT FROM AUTHOR]

Objective: Secoisolariciresinol diglucoside (SDG) is a phytoestrogen that has been reported to improve postmenopausal osteoporosis (PMOP) caused by estrogen deficiency. In our work, we aimed to investigate the mechanism of SDG in regulating the expressions of ERs on PMOP model rats. Methods: Ovariectomization (OVX) was used to establish PMOP model in rats. The experiment was allocated to Sham, OVX, SDG and raloxifene (RLX) groups. After 12-week treatment, micro-CT was used to detect the transverse section of bone. Hematoxylin and Eosin staining and Safranine O-Fast Green staining were supplied to detect the femur pathological morphology of rats. Estradiol (E2), interleukin-6 (IL-6), bone formation and bone catabolism indexes in serum were detected using ELISA. Alkaline phosphatase (ALP) staining was used to detect the osteogenic ability of chondrocytes. Immunohistochemistry and Western blot were applied to detect the protein expressions of estrogen receptors (ERs) in the femur of rats. Results: Compared with the OVX group, micro-CT results showed SDG could lessen the injury of bone and improve femoral parameters, including bone mineral content (BMC) and bone mineral density (BMD). Pathological results showed SDG could reduce pathological injury of femur in OVX rats. Meanwhile, SDG decreased the level of IL-6 and regulated bone formation and bone catabolism indexes. Besides, SDG increased the level of E2 and conversed OVX-induced decreased the expression of ERα and ERβ. Conclusion: The treatment elicited by SDG in OVX rats was due to the reduction of injury and inflammation and improvement of bone formation index, via regulating the expression of E2 and ERs. [ABSTRACT FROM AUTHOR]

PbSe nanotubes (NTs) were synthesized through a low cost, facile and green hydrothermal route in combination with the assistance of ascorbic acid. In the hydrothermal reaction process, Se nanowires were not only used as templates, but also as a Se ion source to provide Se precursors for the growth of PbSe NTs. The prepared tubular crystals with a cubic structure have a length of 1–6 μm and an average diameter of ∼120 nm. Experimental results show that the amount of ascorbic acid and Pb2+ concentration play important roles in the formation of PbSe NTs, and a possible growth mechanism of PbSe NTs has also been presented. Additionally, the photocatalytic activity of the PbSe NTs was investigated and the results establish that PbSe NTs, in the presence of H2O2, showed a high photodegradation efficiency for methylene blue (MB). A probable photocatalytic mechanism for PbSe NTs is also discussed. [ABSTRACT FROM AUTHOR]

To improve optoelectronic properties of bismuth oxyhalides, hybrid BiOX photocatalytic materials have draw a great attention, because of the separation of photogenerated electron-hole pairs. The band offset and band alignments are considered as the key parameters to elaborate carrier transport properties in heterojunction. In this paper, to determine the band alignment of BiOCl and ZnO heterostructure, BiOCl/ZnO core shell nanosheets with different thickness of shell layer were synthesized. The valence band offset (VBO or ΔEV) of BiOCl/ZnO heterostructure was determined using X-ray Photoelectron Spectroscopy measurements. The ΔEV value of 0.294 ± 0.10 eV was calculated by using the Zn 2p3/2, Bi 4f5/2 binding energies as references. Taking the band gaps of 3.37 eV and 3.4 eV for ZnO and BiOCl samples into consideration, respectively, we obtained the type-II band alignment of BiOCl/ZnO heterostructure with a conduction band offset (CBO or ΔEc) of 0.324 ± 0.10 eV. [ABSTRACT FROM AUTHOR]

Two clusters with formula [Ln 4 (μ 4 -O)(HL) 3 (SCN) 4 (H 2 O) 2 ] (Ln = Dy ( 1 ), Er ( 2 )) were assembled by the hydrothermal reaction of Ln(SCN) 3 hydrate and symmetrical amidate H 3 L ligand (2-hydroxy-N-[2-hydroxy-3-[(2-hydroxybenzoyl)amino]propyl]benzamide) in the presence of triethylamine. X-ray crystallographic analysis reveals that 1 and 2 are isostructural and are tetranuclear with a μ 4 -O centred Ln 4 tetrahedron core, in which four crystallographically unequivalent lanthanide ions are all seven-coordinated in distorted capped octahedron geometries. Significantly, both clusters show chirality that is induced by coordination of spirally twisted ligands. The magnetic properties of 1 and 2 have been investigated. Both clusters do not exhibit slow magnetic relaxation that may be ascribed to the effect of the symmetry of ligand field on the oblate Dy 3+ and prolate Er 3+ ions, as well as the regular tetrahedral core. [ABSTRACT FROM AUTHOR]

Background: Classical swine fever (CSF) is a severe disease of pigs that results in huge economic losses worldwide and is caused by classical swine fever virus (CSFV). CSFV nonstructural protein 4 A (NS4A) plays a crucial role in infectious CSFV particle formation. However, the function of NS4A during CSFV infection is not well understood. Results: In this study, we used RNA-seq to investigate the functional role of CSFV NS4A in PK-15 cells. A total of 3893 differentially expressed genes (DEGs) were identified in PK-15 cells expressing NS4A compared to cells expressing the empty vector (NC). Twelve DEGs were selected and further verified by RT‒qPCR. GO and KEGG enrichment analyses revealed that these DEGs were associated with multiple biological functions, including cell adhesion, apoptosis, host defence response, the inflammatory response, the immune response, and autophagy. Interestingly, some genes associated with host immune defence and inflammatory response were downregulated, and some genes associated with host apoptosis and autophagy were upregulated. Conclusion: CSFV NS4A inhibits the innate immune response, and suppresses the expression of important genes associated with defence response to viruses and inflammatory response, and regulates cell adhesion, apoptosis and autophagy. [ABSTRACT FROM AUTHOR]

With the severe spectrum shortage in conventional cellular bands, large-scale antenna systems in the mmWave bands can potentially help to meet the anticipated demands of mobile traffic in the 5G era. There are many challenging issues, however, regarding the implementation of digital beamforming in large-scale antenna systems: complexity, energy consumption, and cost. In a practical large-scale antenna deployment, hybrid analog and digital beamforming structures can be important alternative choices. In this article, optimal designs of hybrid beamforming structures are investigated, with the focus on an N (the number of transceivers) by M (the number of active antennas per transceiver) hybrid beamforming structure. Optimal analog and digital beamforming designs in a multi-user beamforming scenario are discussed. Also, the energy efficiency and spectrum efficiency of the N ? M beamforming structure are analyzed, including their relationship at the green point (i.e., the point with the highest energy efficiency) on the energy efficiency-spectrum efficiency curve, the impact of N on the energy efficiency performance at a given spectrum efficiency value, and the impact of N on the green point energy efficiency. These results can be conveniently utilized to guide practical LSAS design for optimal energy/ spectrum efficiency trade-off. Finally, a reference signal design for the hybrid beamform structure is presented, which achieves better channel estimation performance than the method solely based on analog beamforming. It is expected that large-scale antenna systems with hybrid beamforming structures in the mmWave band can play an important role in 5G. [ABSTRACT FROM PUBLISHER]

Highlights: [•] A series of BiOIαCl1-α solid solution electrode were successfully prepared through a simple electrodeposition method. [•] All prepared BiOIαCl1-α electrodes exhibited p-type conductivity. [•] The BiOIαCl1-α solid solution showed the best photoelectrochemical activity at α =0.5. [Copyright &y& Elsevier]

[Display omitted] • Atomic doping combine surface ion graft is first time used to boost photocatalytic. • Atomic doping effect is systematically studied for the optimal heteroatomic doping. • Atom doping and surface ion graft synergistically manipulate photocharges separation. The synergistic implementation of atomic-level charge separation strategies for bulk–surfaces is a meaningful study that fundamentally addresses the shortcomings of single materials. Here, we report for the first time the atomic-level engineering of atomic doping in combination with surface ion grafting, which can be coordinated to significantly facilitate photocatalytic H 2 evolution. More impressively, the study systematically investigated the atomic doping effects of Fe, Co, Ni and Cu atoms, and analyzed the conditions for optimal doping with experimental and theoretical calculations. The doping of variable valence Cu atoms leads to the emergence of newly occupied electronic states at the Fermi energy level, which effectively improves the carrier separation. The X-ray absorption spectroscopy (XAS) results verified the precise coordination environments of the doped Cu atoms, as well as confirmed the solid grafting of Ni ions on the catalyst surface. Furthermore, the hydrogen production rate of 1.2 % Cu–Zn 0.67 Cd 0.33 S–0.5 wt% Ni reached 38.17 mmol/g/h, corresponding to an apparent quantum efficiency of 35.5 %, which is 82.8 times higher than that of pure ZCS. Besides, the H 2 production rate can reached 118.73 mmol/g/h without cooling. Meanwhile, the synergistic strategy of manipulating the bulk and surface photo-charges of Zn 0.67 Cd 0.33 S also effectively enhances the photothermal effect and further improves its photocatalytic performance. This work provides different inspirations for bottom-up design of efficient photocatalysts to achieve synergistic facilitation strategies. [ABSTRACT FROM AUTHOR]

Reasonable design of multi-compositions electrode material with hierarchical structure can effectively enhance the electrochemical performance of electrode. Here, the hierarchical structure of MoS 2 /Co 3 S 4 /Ni 3 S 4 (CMS) nanosheet-on-nanorod arrays have been synthesized through a simple in situ hydrothermal. The growth process is proposed according to the morphology evolution on hydrothermal time. The hierarchical structure obtained through optimized time enhances the accessible surface area for electrolyte, and multi-compositions provide rich redox reactions. Therefore, the hierarchical CMS electrode exhibits a high areal capacitance of 3.94 F cm−2 at 5 mA cm−2, and prominent cycle stability with 91.8% retention after 5000 cycles. These results demonstrate that the CMS electrode developed in this study has good potential for high-performance supercapacitors. • The hierarchical MoS 2 /Co 3 S 4 /Ni 3 S 4 nanosheet-on-nanorod arrays have been synthesized by an in-situ hydrothermal method. • The growth mechanism is proposed according to the morphology evolution on hydrothermal time. • The hierarchical structure provides abundant active sites and multi-compositions provide rich redox reactions. • The MoS 2 /Co 3 S 4 /Ni 3 S 4 electrode exhibits a high areal capacitance and prominent cycle stability. [ABSTRACT FROM AUTHOR]

The integration of highly accessible electro‐active sites and the high conductivity can enhance the catalytic performance of catalysts. Herein, we report a facile ambient growth of FeOOH nanosheets (NSs) on the surface of Ti3C2 nanosheets to fabricate the hierarchical FeOOH NSs/Ti3C2. The hierarchical structure efficiently suppresses agglomeration of nanosheets to expose maximal electro‐active surface, and provides strong interfacial interaction between FeOOH and Ti3C2 that facilitates fast charge transfer, leading to enhanced electrocatalytic performance. Specifically, the FeOOH NSs/Ti3C2 achieves a current density of 10 mA cm−2 at 1.63 V vs RHE with a Tafel slope of 95 mV dec−1, and possesses excellent OER stability with negligible attenuation of current density after 30 h. This work represents that growth of poor conductive active materials on 2D MXene can boost the catalytic performance of electrocatalyst. [ABSTRACT FROM AUTHOR]

Self‐supported hollow nanoarrays with rich active sites hold great promise as binder‐free electrode for supercapacitors. In this work, the hollow Co‐Ni−S nanowedge arrays (NWAs) have been fabricated on Ni foam (NF) substrate through a facile sulfidation and etch of ZIF−L‐Co NWAs/NF. Structural evolution upon solvothermal time indicates that the formation of hollow Co‐Ni−S NWAs is mainly due to the etch of defect‐rich interior of solid ZIF−L‐Co NWAs. The unique hollow nanowedge structural and compositional advantages ensure the hollow Co‐Ni−S NWAs excellent electrochemical properties with areal capacity of 0.286 mA h cm−2 at 5 mA cm−2, and 78% capacity retention after 2000 cycles. Moreover, the hybrid supercapacitor (HSC) of Co‐Ni−S // AC has been assembled, which illustrates good application performance. The results indicate that the Co‐Ni−S NWAs/NF is a promising binder‐free electrode for high‐performance hybrid supercapacitors. [ABSTRACT FROM AUTHOR]

• Atomic layer Co 3 O 4-x nanosheets (1 nm) are synthesized. • Robust OER and ORR activities are achieved for atomic layer Co 3 O 4-x nanosheets. • Rechargeable ZAB performance of Co 3 O 4-x nanosheets is 1.7 fold than Pt/C-IrO 2. Stable and efficient bifunctional electrocatalyst for air electrode is still of challenge for rechargeable zinc-air batteries (ZABs). Here, we report an atomic layer oxygen defect cobalt oxides (Co 3 O 4-x) nanosheets (1 nm) as efficient electrocatalyst for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Due to the atomic layer nanosheets, more oxygen defects are formed during plasma treatment enabling effective OER catalysis with overpotential of only 309 mV, which is lower compared to benchmarking IrO 2 (313 mV). Meanwhile, a Pt-like ORR activity is achieved for Co 3 O 4-x due to the atomic layer nanosheets with highly exposed active sites and loosened binding strength between Co3+ and O 2 /OH−. The battery performance of Co 3 O 4-x nanosheets is 1.7 times higher than that of Pt/C-IrO 2 based ZABs. Besides, Co 3 O 4-x nanosheets exhibit undetectable degradation in battery performance after galvanostatic discharge-charge with 5 mA cm−2 for 150 h implying the superior stability of the atomic layer Co 3 O 4-x nanosheets. All-solid-sate ZABs fabricated from Co 3 O 4-x nanosheets perform an impressive power density of 57 mW cm−2 and stable galvanostatic discharge-charge voltage for 2 h demonstrating that Co 3 O 4-x nanosheets can be utilized as air electrode for practical application. [ABSTRACT FROM AUTHOR]

The binary transition metal sulfides are highly desirable electrode materials for high-performance supercapacitors, thanks for their excellent electrochemical activity and electrical conductivity. Herein, the hierarchical FeCo 2 S 4 arrays are designed and constructed on Ni foam, which consists of microsheets anchored nanosheets. The FeCo 2 S 4 hierarchical structure provides high conductivity and abundant electroactive sites as well as facial and short ion transport paths. Therefore, the FeCo 2 S 4 electrode achieves an excellent specific capacitance of 2488.50 F g−1 (7.66 F cm−2) at 5 mA cm−2, and a high level of cycle stability of 95.67% retention after 5000 cycles. The FeCo 2 S 4 //activated carbon (AC) device delivers the maximal energy density of 44.89 W h kg−1 and the maximal power density of 4015.56 W kg−1. The impressive electrochemical properties of hierarchical FeCo 2 S 4 arrays make it a promising high-performance electrode for hybrid supercapacitors. Hierarchical nanosheets-anchored-on-microsheets FeCo 2 S 4 array exhibits an excellent specific capacitance of 2488.50 F g−1 (7.66 F cm−2) at 5 mA cm−2, and significant cycle stability retaining 95.67% of initial capacitance after 5000 cycles, which indicates great potential for practical applications in electrochemical energy storage. Image 1 • The hierarchical nanosheets-anchored-on-microsheets FeCo 2 S 4 arrays have been designed and synthesized. • The FeCo 2 S 4 hierarchical structure provides high conductivity and abundant exposed electroactive sites. • The FeCo 2 S 4 electrode exhibits an excellent specific capacitance of 2488.50 F g−1 (7.66 F cm−2) at 5 mA cm−2. • The FeCo 2 S 4 //AC delivers the maximal energy density of 44.89 W h kg−1 and the maximal power density of 4015.56 W kg−1. [ABSTRACT FROM AUTHOR]

The efficient carrier transfer and accumulation achieved by the Bi 2 Te 3 /Te/C NWs could explain the hydrogen production and improved degradation performance of organic dyes in the presence of NaBH 4. [Display omitted] • A simple Bi 2 Te 3 /Te/C NWs catalyst with a high specific surface area was prepared. • Without precious metals, the catalytic degradation of MB and MO was completed rapidly in 20 and 150 s, respectively. • In scaled-up organic dye degradation/hydrogen production experiments, fast and efficient H 2 production can be realized. • The mechanism of synergistic organic dye degradation and hydrogen production is proposed. Over-consumption of limited fossil fuels has caused serious environmental pollution and a global energy crisis, threatening human life and biodiversity. As an ideal, environmentally friendly renewable energy, hydrogen can satisfy human clean energy requirements. Therefore, whether hydrogen can be catalytically generated in the wastewater treatment process is a highly meaningful investigation. Herein, Bi 2 Te 3 /Te/C heterojunction nanowires with high specific surface area and rich pore structure were successfully synthesized. The efficient catalytic degradation process is accompanied by the generation of hydrogen. The catalytic degradation of methylene blue and methyl orange was achieved in less than 20 s and 150 s, respectively. Meanwhile, in scaled-up degradation/hydrogen production experiments, fast and efficient H 2 production from NaBH 4 can be realized in the presence of Bi 2 Te 3 /Te/C nanowires. The mechanism of efficient synergistic organic dye degradation and hydrogen production is due to the efficient carrier transfers and accumulation at the hetero-interface. In contrast to previous work, rapid degradation of organic dyes and hydrogen production by decomposition of NaBH 4 were achieved without the help of high-cost catalysts such as precious metals. This work could provide an alternative pathway for the future degradation of organic matter in synergistic heterogeneous catalytic wastewater and recovery of by-products including hydrogen. [ABSTRACT FROM AUTHOR]

Abstract The flower-like Co 9 S 8 microballs assembled with weak crystalline pea pod-shaped nanowires were fabricated via a one-pot hydrothermal reaction. The high-resolution TEM image of pea pod-shaped nanowires revealed a weak crystalline structure. Some regions were amorphous and some regions showed well-resolved lattice fringe. Because flower-like Co 9 S 8 microballs possessed the more catalytic active sites of the weak crystalline character and the fast electron transfer along the nanowires, they would be promising catalysts for reduction of I 3 − in DSSCs and electrochemical water splitting. As the counter electrode catalysts for I 3 − reduction, DSSCs based on the Co 9 S 8 microballs got a high photoelectrical conversion efficiency of 7.0%, which was comparable with DSSCs based on standard platinum (7.48%). As the electrocatalysts for hydrogen evolution reaction, the Co 9 S 8 microball electrode possessed an overpotential of 173.8 and 191.3 mV at the current density of 10 mA cm−2 in acid and alkaline solution, respectively. Also, it displayed a superior catalytic activity for oxygen evolution reaction. The stability tests indicated that this microball could possess the high catalytic activity with long time. This kind of Co 9 S 8 microballs assembled with weak crystalline pea pod-shaped nanowires paved a new way to low-cost catalyst for I 3 − reduction and water splitting. Highlights • Co 9 S 8 microballs assembled with weak crystalline pea pod-shaped nanowires. • Co 9 S 8 microball electrode possessed a good overpotential for HER. • DSSCs based on it got a high photoelectrical conversion efficiency of 7.0%. [ABSTRACT FROM AUTHOR]

Abstract: Despite high‐energy density and low cost of the lithium–sulfur (Li–S) batteries, their commercial success is greatly impeded by their severe capacity decay during long‐term cycling caused by polysulfide shuttling. Herein, a new phase engineering strategy is demonstrated for making MXene/1T‐2H MoS2‐C nanohybrids for boosting the performance of Li–S batteries in terms of capacity, rate ability, and stability. It is found that the plentiful positively charged S‐vacancy defects created on MXene/1T‐2H MoS2‐C, proved by high‐resolution transmission electron microscopy and electron paramagnetic resonance, can serve as strong adsorption and activation sites for polar polysulfide intermediates, accelerate redox reactions, and prevent the dissolution of polysulfides. As a consequence, the novel MXene/1T‐2H MoS2‐C‐S cathode delivers a high initial capacity of 1194.7 mAh g−1 at 0.1 C, a high level of capacity retention of 799.3 mAh g−1 after 300 cycles at 0.5 C, and reliable operation in soft‐package batteries. The present MXene/1T‐2H MoS2‐C becomes among the best cathode materials for Li–S batteries. [ABSTRACT FROM AUTHOR]

It is important to synthesize environmentally friendly transition metal sulfide catalysts with superior performance for electrochemical water splitting and reduction of I3− in dye-sensitized solar cells (DSSCs). In this work, cubic (Fe0.5Ni0.5)S2 nanocrysals with a monodispersed size of ca. 10 nm were successfully prepared via a hot-injection reaction with a Schlenk line system. Because of the FeNi-oleate complex as transition metal source, no other by-products were produced. The (Fe0.5Ni0.5)S2 nanocrystal/carbon black composite with different nanocrystal contents was control fabricated. Because the composite possessed two merits, more catalytically active sites of nanocrystals and fast electron transfer of carbon black, it is a promising catalyst for electrochemical water splitting and reduction of I3− in DSSCs. As the counter electrode catalysts for reduction of I3−, DSSCs based on the composite with 57% (Fe0.5Ni0.5)S2 nanocrystal contents have a high power conversion efficiency of 6.71%, which was comparable to Pt-based DSSCs (7.05%). The electrochemical measurement showed that (Fe0.5Ni0.5)S2 nanocrystals had a good catalytic activity for reduction of I3−. As the catalytic electrode for hydrogen evolution reaction (HER), the composite electrode with 57% (Fe0.5Ni0.5)S2 nanocrystal contents displayed an overpotential of 250 mV to reach the current density of 10 mA cm−2 in alkaline solution. It retained good HER activity for 1000-cycle measurements. The density functional theory showed the free energy of hydrogen adsorbed on the Ni site near S defects was − 0.12 eV, which was smaller than that of the Fe site near S defects. So, the Ni site near S defects of (Fe0.5Ni0.5)S2 was the main catalytically active site for HER. Also, the (Fe0.5Ni0.5)S2 nanocrystals displayed good electrocatalytic activity for oxygen evolution reaction. This type of double metal sulfide with monodispersed size paves the way for new insight into earth-abundance catalysts for water splitting and I3− reduction. [ABSTRACT FROM AUTHOR]

In this work, the sesame ball-like CoS/MoS 2 nanospheres were controllably synthesized via a facile hydrothermal and solvothermal consecutive reaction. MoS 2 nanospheres were preferentially formed by assembly of nanosheets during the hydrothermal reaction. And then CoS nanoparticles were grown on the surface of MoS 2 nanosheets during the solvothermal reaction method. Due to the space confinement effect, CoS grew as nanoparticles with size of 5 nm between MoS 2 nanosheets, and the nanosheets assembled into nanospheres to get the sesame ball-like structure. Because this composite possessed two merits, that is, more active sites of CoS nanoparticles and high conductivity of MoS 2 nanospheres, DSSCs based on this sesame ball-like CoS/MoS 2 nanospheres got a higher power conversion efficiency of 7.48%, which was higher than that based on the solo CoS (7.10%) and solo MoS 2 (4.84%). And it was similarly to the DSSCs based on Pt cathode (7.51%). Their excellent electrocatalytic activities for the I 3 − /I − redox reaction was confirmed by cyclic voltammetry, electrochemical impedance spectra and Tafel polarization measurements. Density functional theory was also used to calculate the adsorption of I 3 − on the surface of CoS/MoS 2 , and the adsorption energy and bond length results indicated Co atoms were the main catalytic active site for I 3 − reduction. The hybrid interactions took place between p orbital of I and 3d states of Co, which lead to I 3 − was activated and dissociated easily. [ABSTRACT FROM AUTHOR]

It is important to prepare an environmental-friendly and earth-abundant electrocatalyst with excellent performance and superior stability for efficient hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, a facile precursor route is developed to synthesize CoP nanostructure with different morphologies just by controlling the hydrothermal reaction temperature and time. The precursor Co(CO 3 ) 0.5 OH·0.11H 2 O (CHCH) nanowire (NW) and uniform flower-like microball (MB) with exposed (001) facet were firstly successfully prepared at hydrothermal reaction temperature of 115 °C for 3 h and 10 h, respectively. And then a phosphorization treatment of CHCH was performed to get CoP NWs and flower-like CoP MBs assembled with ordered NWs that exposed (002) facets. The CoP MBs exhibit a lower over-potential of 105.3 mV at the current density of 10 mA cm −2 , and a smaller Tafel slope of 53.5 mV·dec −1 in 0.5 M H 2 SO 4 solution for HER. Furthermore, this hierarchical structure could possess its good activity for 40,000 s. The catalyst also shows an excellent activity with the overpotential of 97.3 mV at 10 mA cm −2 , and a Tafel slope of 84.3 mV·dec −1 in 1 M KOH solution for HER. The density functional theory (DFT) calculations further reveal that hydrogen adsorbed on all P sites of CoP could result in smaller adsorption energy (0.085 eV), which is comparable to Pt. So, all P sites are the main active sites for HER. Also, these flower-like CoP MBs could display a good electrocatalytic activity for OER. Compared to disordered CoP NWs, the flower-like CoP MBs exhibit a better HER and OER performance because this hierarchical structure possessed two merits, that is, the fast vectorial electron transfer along the ordered NWs and improved inherent activity of each active site due to the exposed (002) facet. This low-cost and high-activity hierarchical structure is an efficient catalyst for HER and OER. [ABSTRACT FROM AUTHOR]

Four tetranuclear lanthanide compounds with formulas [Ln4(HL)2(H3L)2(H2L′)2(PhCOO)2]·6CH3OH (Ln = Nd (1), Sm (2) and Gd (3)) and [Dy4(DFMP)2(H2L)2(HL)2]·6CH3OH·2H2O (4) (H4L = 3-((1,3-dihydroxy-2-(hydroxymethyl)propan-2-ylimino)methyl)-2-hydroxy-5-methylbenzaldehyde and H3L′ = 3-(4,4-bis(hydroxymethyl)oxazolidin-2-yl)-2-hydroxy-5-methylbenzaldehyde) have been successfully synthesized by a one-pot route at room temperature. The in situ polydentate ligands reveal various coordination modes in forming compounds 1–4. Structure analysis reveal that all four compounds have a centrosymmetric “parallelogram” core, where four μ3-CH2O– arms are linked on both sides of the Ln4 plane in compounds 1–3, while two μ3-CH2O– arms connected Dy4 in compound 4. In addition, magnetic susceptibility studies reveal that compound 4 shows single-molecule magnet (SMM) behaviour with a high-temperature energy barrier of 50.2 K and a low-temperature energy barrier of 4.5 K. The relaxation behaviour is probably attributed to the individual Dy ions and the magnetic coupling between neighboring Dy ions. [ABSTRACT FROM AUTHOR]

The TiO 2-X /BiOI S-scheme heterostructure energy band structure modulated by defect engineering is creatively proved by a novel approach. [Display omitted] • A facile hierarchical S-scheme photocatalysts TiO 2-X /BiOI composite are prepared. • Regulation of S-type heterojunction by oxygen defect engineering. • TiO 2-X /BiOI composite possessed excellent and robust H 2 evolution rate. • Improved light utilization and accelerated electron separation and migration are underlying reasons. • Possible charge transfer mechanism based on an S-scheme heterojunction is intuitively proved through a novel method. The efficiency of hydrogen production via semiconductor photocatalysts is currently limited by poorly light adsorption, rapid recombination of photogenerated carriers, ineffective surface catalytic behavior, and field-instability. Herein, a hierarchical S-scheme photocatalyst composite of BiOI nanosheets (NS) with Ti3+ self-doped black TiO 2-X mesoporous nanospheres (MS) was prepared, from which we observed an improve light utilization, as well as the accelerated separation and migration of photogenerated carriers. Furthermore, the optimized TiO 2-X /BiOI heterostructure exhibited a robust H 2 evolution rate of 794.28 μmol g−1h−1, which was approximately 9.2 and 3 times that of pure BiOI NS and TiO 2 MS, respectively. The photocatalytic mechanism of S-scheme heterostructure between black TiO 2-X and BiOI was proposed by combining upconversion spectrum, low temperature photoluminescence spectrum and theoretical calculations. This work provides not only a facile synthetic method to prepare the heterojunction structures with high catalytic activity, but also establishes a platform for future materials-by-design with S-scheme energy band structures. [ABSTRACT FROM AUTHOR]

The increasing incidence of diseases affecting the central nervous system (CNS) demands the urgent development of efficient drugs. While many of these medicines are already available, the Blood Brain Barrier and to a lesser extent, the Blood Spinal Cord Barrier pose physical and biological limitations to their diffusion to reach target tissues. Therefore, efforts are needed not only to address drug development but specially to design suitable vehicles for delivery into the CNS through systemic administration. In the context of the functional and structural versatility of proteins, recent advances in their biological fabrication and a better comprehension of the physiology of the CNS offer a plethora of opportunities for the construction and tailoring of plain nanoconjugates and of more complex nanosized vehicles able to cross these barriers. We revise here how the engineering of functional proteins offers drug delivery tools for specific CNS diseases and more transversally, how proteins can be engineered into smart nanoparticles or ‘artificial viruses’ to afford therapeutic requirements through alternative administration routes. [ABSTRACT FROM AUTHOR]

A novel hedgehog-like ZnO/SnO 2 hierarchical heterostructures composing of one-dimensional ZnO nanorods (NRs) and three-dimensional SnO 2 octahedron nano-blocks (ONBs) have been successfully prepared on ITO substrate through a simple solution method. The results show that ZnO NRs are uniformly and densely distributed perpendicular to the surface of the SnO 2 ONB. The as-prepared ZnO NRs/SnO 2 ONB (Z/S) hierarchical heterostructure is applied to assemble ultraviolet photodetector (UVPD). Under UV light illumination, it can obviously find that the Z/S UVPD can work at zero bias voltage and exhibits a remarkable stability and repeatability. In addition, the Z/S UVPD displays excellent characteristics over that based on SnO 2 ONBs, in particular a relatively high photoresponsivity, a strong photocurrent density of 0.94 mA cm−2, together with a high on/off ratio of 5362. Moreover, the possible mechanisms for growth and UV detection on the hedgehog-like Z/S hierarchical heterostructure have been discussed. [ABSTRACT FROM AUTHOR]