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Electrocatalytic nitrate reduction reaction (NO 3 -RR) for sustainable carbon-free hydrogen carrier (NH 3) production from polluted NO 3 - sources of industrial wastewater is very promising. Mo-based catalysts are defined as popular electrocatalytic materials, but the rational performance achievement of Mo-based catalysts in the NO 3 -RR remains limited. In this study, to overcome the NO 3 -RR activity limitation, the interfacial MoO 2 nanograins assembled on the N-functional carbon nanofibers (defined as MoO 2 /C) were constructed by electrospun and controlled graphitizing process. The comparative catalysts dominated by molybdenum oxides namely MoO 2 /MoO 3 were synthesized by controlled calcination in air atmosphere. The MoO 2 nanograins anchored in situ on carbon nanofibres could afford more interfacial active regions and accelerate the electron transfer efficiency of the electrocatalytic process by graphitic carbon fiber network. More importantly, MoO 2 /C was endowed with more oxygen vacancy sites which can trap the free NO 3 - ions over the reactive sites to enhance the surface interaction of NO 3 - with catalytic sites during the reaction process. The experimental results showed that the electrocatalytic nitrate reduction performance of the catalyst MoO 2 /C obviously outperformed that of MoO 2 /MoO 3 in the light of the atomic activity efficiency with a near 7.5 folds enhancement. The MoO 2 /C affords the highest NH 3 yield of 4838.5 µg h−1 mg cat −1 and Faraday efficiency of 30 % at –0.9 V vs.RHE and was endowed with 50 h of continuous reaction stability, proving the potential in practical electrochemical water treatment involving nitrate contamination. [Display omitted] • The interfacial MoO 2 nanograins assembled on the N-functional carbon nanofibers. • The interfacial catalyst affords more interfacial active regions and accelerate the electron-transfer-efficiency. • MoO 2 /C affords more oxygen vacancy sites which can trap the free NO 3 - ions. • MoO 2 /C shows a near 7.5 folds atomic activity enhancement of MoO 2 /MoO 3. [ABSTRACT FROM AUTHOR]

Humans have innately established close and profound ties with the, and through these relationships shaped many kinds of landscapes. Among these are sacred landscapes, which have drawn the attention of researchers due to their cultural significance. In the field of health geography, large-sized sacred regional landscapes are now the focus of studies for their therapeutic properties. However, few scholars have focused on small sacred landscape systems at the community level (constructed by local communities) or the physical and psycological health benefits that these landscapes offer to the local residents. These small-sized and widespread, but often hidden, sacred landscapes are closely tied to people's daily lives and work. They have evolved and grown over millennia to become critical sociocultural phenomena. This study takes the sacred bao ye landscape of the Dong people of China as the research subject. By adopting the case study approach, field research, semi-structured interviews, and textual analysis, it summarizes the types, geographical distribution, rituals and processes of bao ye as a sacred landscape of the Huanggang village in Guizhou Province, and concludes with an analysis of motivation and health benefits to the bao ye worship. In this paper we argue that bao ye is a sacred landscape system focusing on the healthy development of children, and constitutes a local belief developed in an isolated environment lacking medical resources, which remains in practice. The sacred landscape of bao ye offers a therapeutic environment, providing children with increased opportunities to engage with and build deep connections to nature. Thruogh this process children may develop a bond with nature that inspires them to protect nature on their own accord. We argue that bao ye offers an important case study for understanding the landscape-people-healing interactivity at the community level. • Sacred landscapes have beneficial effects on the physical and mental health of humans. • The community-level sacred landscape of Bao ye is important for the healthy development of local children. • The sacred landscape system of the Dong people helps to better protect this precious traditional cultural landscape. [ABSTRACT FROM AUTHOR]

[Display omitted] • Interaction of flavor substances in sesame-flavor baijiu was studied firstly. • Volatile change was the reason for the interaction affecting the flavor perception. • Structure and phase ratio affected the volatility of esters. • The interaction prediction model is established firstly to realize rapid judgment. The interaction between 1,3-dimethyltrisulfide and aroma-active compounds in sesame-flavor baijiu was evaluated by Feller's additive model and Odor Activity Value Approach, and the reason for the interaction can promote the release of fruity and caramel aromas of ethyl caproate, ethyl was explored by the Partition Coefficient Approach. The interaction results indicated that 1,3-dimethyltrisulfide caprate and furan-2-ylmethanol. Others showed masking effect. The Partition Coefficient showed that the effect of 1,3-dimethyltrisulfide on the volatility of esters was one of the reasons for the interaction affecting the flavor perception, and the volatility of ethyl esters with longer carbon chains at high phase ratio (PRs) is more likely to be promoted. Besides, the prediction model was initially proposed: y = 2.0112 ln(x) + 0.1461, which indicated that esters with the olfactory threshold lower than 33.80 μg/L are more likely to have positive effects with 1,3-dimethyltrisulfide, the negative effect is more likely to occur conversely. [ABSTRACT FROM AUTHOR]

• Melanoidins were mostly produced during distillation. • Melanoidins were primarily composed of carbohydrates. • Melanoidins formed during fermentation and distillation had structural differences. • Carbohydrates, proteins and phenols are involved in melanoidin formation diversely. Chinese liquor (baijiu) is a typical fermented food. In which production, melanoidins are formed in fermenting grains during low-temperature fermentation with long-term, and in distilled grains with high-temperature distillation for short-term. Here, the formation and structural characterization of melanoidins in these two distinct stages were first investigated through chemical composition analysis and spectroscopic identification. Our research showed that proteins and phenols continuously participate in melanoidin formation during fermentation and distillation processes. Distillation could produce melanoidins with larger amounts, darker colors, higher molecular weights, and more stable states than fermentation. The chemical composition including 10 carbohydrates, 17 amino acids, 5 free phenolic acids, and 7 bound phenolic acids was successfully identified in melanoidins. Ion chromatography was proposed to be an efficient method to investigate carbohydrates in melanoidins. Moreover, the potential impact of microorganisms on melanoidins was first revealed to be the possible utilization of glucose in melanoidins. [ABSTRACT FROM AUTHOR]

Based on the standardized Euclidean distance method, an evaluation theory for sustainable agricultural development was constructed, which includes a sustainable agricultural development model, an evaluation function model, a sustainable agricultural development exponent (SADE), a rank of the sustainable agricultural development, an index frame of the sustainable agricultural development, a goal system, and a zero system. Data from Zhenyuan County of Gansu province (ZYC) between 2000 and 2012 was used as a case study of the theory. The SADE of ZYC was [0.34, 0.90], and the agriculture system exhibited low sustainability from 2000 to 2003, mid sustainability from 2004 to 2007, and high sustainability from 2008 to 2012. The results explained the actual ZYC situation, and showed that the Euclidean distance method of sustainable agricultural development is feasible. The innovativeness and merits of the method include: (1) reliable methodology, (2) construction using goal and zero systems, which serve as reference systems of sustainable agricultural development and allow control of the evaluation, and (3) index weights embedded in the evaluation function, which prevents errors or mistakes in the expert scoring method and prevents the reassignment of index weights due to adding or subtracting indicators. The main reasons that the SADE increased in ZYC include suitable chemical fertilization and pesticide application, enhancement of conservation farming areas, soil testing and fertilizer-formulated areas, and drinking water security in rural and non-disaster crop areas. The main problems with increasing the SADE in ZYC include straw application and low farmer income, both of which should be increased. [ABSTRACT FROM AUTHOR]

• High-frequency resonance is suppressed by broadband MMC impedance reshaping. • Phase compensation is adopted to eliminate the negative damping of MMC. • The proposed method is effective under various operating scenarios of ac grid. • A controller parameter design method is presented in detail. Negative damping in modular multilevel converter (MMC) impedance may lead to high-frequency resonance (HFR) in MMC-high-voltage direct current systems. The existing solution is based on amplitude attenuation by digital filters. However, filters have weak amplitude attenuation and obvious phase shifts in the attenuation band, resulting in the transfer of negative damping. The system still has a risk of HFR when grid condition is changed. This study proposed a broadband active damping method based on phase compensation to address this limitation. The embedding position and scheme of the phase compensation controller are optimally designed through impedance-based analysis. By tuning parameters correctly, the negative damping of MMC is eliminated over a wide frequency range (500–2000 Hz). Thus, the proposed method performs better in HFR suppressing under varying grid conditions. In addition, considering the harmonic amplification problem caused by the differential link, an inertia link and a proportional link are further employed to increase high frequency impedance magnitude. Time-domain simulations in MATLAB/SIMULINK verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Heterogeneous peroxymonosulfate (PMS) activation for the mineralization of pollutants has attracted growing attention, while alloying bimetal catalysts afford big promises in synergetic catalysis. Here, by an alteration of electrospun precursor, one-dimensional carbon nanofiber (CNF) integrated with Prussian blue analogs (PBA)-derived alloyed fine plasmonic FeNi 3 hybrid catalyst (FeNi 3 @CNF) was constructed by electrospinning technique with subsequent confinement calcination. The amount of PBA in fiber precursor and thermal treatment temperature were alternatively adjusted to control the distribution and concentration of alloyed FeNi 3 in carbon nanofiber. This unique structure combines the advantages of abundant internal porosity of N-doping carbon fiber and uniforms active FeNi 3 alloys with highly-exposed reactive sites, facilitating the electron transport and proximity of reactant molecules in catalytic oxidation. The synergistic and interfacial effect of optimal FeNi 3 @CNF endowed the ultra-fast degradation activity against bisphenol A (BPA) through rapid persulphate activation to generate four reactive active species. Specifically, 20 mg L−1 of BPA was completely degraded within 4 min with a reaction rate constant of 2.736 min−1. Impressively, by innovating the utilization of the Prussian blue precursor in electrospinning, the optimal FeNi 3 @CNF shows 18.5, 101.3, and 248.5 times activity enhancement in BPA degradation compared to that of Fe@CNF, Ni@CNF, and Fe&Ni@CNF, revealing the appreciable synergy of bimetallic alloys in PMS activation. In addition, the improved catalytic performance of FeNi 3 @CNF under light irradiation was also simulated, confirming that the enhanced photothermal conversion ability of plasmonic alloys and carbon fiber advance the degradation of BPA. [Display omitted] • Carbon nanofiber bearing alloyed ultrafine plasmonic FeNi 3 is constructed. • The exquisite structure of FeNi 3 @CNF possesses rich porous structure and enhanced charge transfer. • Excellent photothermal catalytic efficiency in BPA degradation can be achieved by FeNi 3 @CNF. • The reinforced intermetallic synergy for catalytic reaction is explored. [ABSTRACT FROM AUTHOR]

In order to enhance utilization of millet straw and reduce fertilizer loss, a novel multifunctional fertilizer (MS-g-PAA/PDMUA) was developed using straw cellulose and linear polymer (PDMUA) by semi-interpenetrating technology. The structure and morphology characterization of MS-g-PAA/PDMUA were measured by fourier-transform infrared, x-ray diffraction, x-photoelectron spectroscopy and scanning electron microscopy techniques, to provide evidence of semi-IPNs networks and component interactions, and the results show that the product exhibited excellent water absorbency (562.3 g/g) and enhanced the soil infiltration. Cumulative release of N, P was 49.2% and 55.1%, respectively, after 40 days, coming up to the Committee of European Normalization (CEN) standard. The agricultural application of MS-g-PAA/PDMUA showed that it could promote growth indexes of wheat, which could improve wheat yields. Therefore, desirable water retention, slow-release properties, and wheat growth effects highlight the product's potential for agriculture application. [Display omitted] ● MS-g-PAA/PDMUA is derived from millet straw, can enhance waste straw utilization. ● The MS-g-PAA/PDMUA is rich in nitrogen and phosphorus, which promote wheat growth. ● The product has excellent water retention and slow fertilizer-release properties. ● Preparing by waste straw can reduce cost, is beneficial to industrial production. [ABSTRACT FROM AUTHOR]

• A steady cone-jet occurs in a greater range of liquid flow rates for a hemispherical capillary. • Varicose and whipping regimes are easily obtained with a hemispherical nozzle. • The transition from varicose and whipping usually depends on interfacial forces on the jet. • A general parameter to determine varicose, transition, and whipping regimes is presented. A cone-jet regime in electrohydrodynamic atomization (EHDA) is widely applied into printing, electro-spinning, spray-coating, and biological mass spectrometry. Regulating different instabilities of jet is crucial for optimizing its operating parameters. In present work, an atypical, hemispherical capillary with inner diameter of 0.40 mm and cap size of 6.20 mm was employed as atomization nozzle, through which a steady cone-jet regime was confirmed versus suitable feeding liquid flow rate and electric potential. A permanent and highly charged jet emits from a Taylor cone apex and further disintegrates into fine highly charged drops in the form of varicose or whipping instabilities. The results indicate that a steady cone-jet is observed in the specific ranges of the feeding liquid flow rate, electric potential and conductivity. The typical breakup instabilities including varicose and whipping are clearly observed with an increase in liquid flow rate for a fixed electric potential for most of liquids, and the transition from varicose to whipping instability easily occurs. For a steady cone-jet, the jet breakup instabilities usually depends on the competition between interfacial forces on the electrified jet. The transition process involving a low-viscosity jet with a large flow rate is observed, and the general parameter G = Γ 2 δ μ 0.52 is calculated to account for surface charge, surface tension, and viscosity effects, where Γ is the electric force to surface tension ratio and δ μ is the inertia to viscous force ratio. Finally, the varicose, transition regime, and whipping are classified with first and second critical threshold values G = 40 and G = 102, respectively. Meanwhile, as the electrified jet transforms from varicose to whipping instabilities, the jet breakup length shows a trend of increasing first and then decreasing. [ABSTRACT FROM AUTHOR]

This study aimed to synthesize the cellulose-modified material [potassium carboxymethylcellulose (CMC-K)] based on wheat straw from straw cellulose by alkalization and etherification so as to enhance the use of waste straw and improve water and fertilizer efficiency. Potassium was introduced through the carboxymethylation of cellulose to supply nutrients to crops. Moreover, the order of influential factors on the water absorption property was determined by an orthogonal experiment. The results showed that the highest water absorbency of 196.2 g/g was achieved for the conditions of 1.5:1 potassium hydroxide to cellulose, 1.5:1 chloroacetic acid to cellulose, 50% potassium hydroxide, and 80% chloroacetic acid. The CMC-K was characterized by Fourier-transform infrared, x-ray diffraction, and scanning electron microscopy techniques, and the results indicated that the product exhibited excellent water-retention ability in the soil and reduced infiltration. The agricultural application of CMC-K promoted the growth indexes of wheat, which improved wheat yields. Moreover, it also increased total nitrogen, ammonium nitrogen, total potassium, and available potassium. The fertilizer efficiency and water-retention behavior of CMC-K encouraged its use as a safe water- and fertilizer-retaining agent and as a soil conditioner in agricultural applications. [Display omitted] • Application of the straw-based CMC-K could achieve utilization of waste straw. • The CMC-K is rich in potassium, could provide fertilizer for crop growth. • The product shows excellent water retention and could prevent water percolation. • The product prepared by straw can reduces cost, is easy for agricultural extension. [ABSTRACT FROM AUTHOR]

• The necking time is independent of electric field in a reasonable range of flow rate. • The transition from dripping to jetting is enhanced by electric field for relatively small tube. • A model for the transition from periodic dripping to jetting is established in an electric field. • A critical criterion for the transition is presented and in reasonable agreement with experiments. A liquid is issued from the outlet of the capillary tube vertically, and drop formation may be in the form of periodic dripping, dripping faucet and jetting, which usually depends on flow rate or Weber number. We consider the critical Weber number (W e C = ρV 0 2 D / σ) at which the transition from periodic dripping to jetting occurs in the presence of an electric field, where high-resolution images are recorded. The necking time is mainly related to nozzle diameter and surface tension, and independent of electric potential and flow rate (in a reasonable range).The first threshold limit decreases with an increase in electric potential, where the dripping faucet is clearly affected and the point of drop detachment gradually increases. When the drop formation is in the form of dripping faucet, the transition from dripping faucet to jetting regime is enhanced by electric potential, where a sudden transition could be observed in an extremely limited range of liquid flow rate. The critical criterion (Weber number) is presented to determine the transition from dripping to jetting in the presence of an electric field. The critical Weber number is in a reasonable agreement with the experiment, although the predicted results are quantitatively divergent with experimental data. [ABSTRACT FROM AUTHOR]

To enhance waste straw utilization and improve fertilizer efficiency, a novel semi-interpenetrating polymer network fertilizer (CMCK-g-PAA/PDMUP) was prepared from straw cellulose and linear polymer by solution polymerization. Polydihydroxymethyl-urea potassium phosphate (PDMUP) was included to supply nitrogen, phosphorus, and potassium nutrients. Characterization of CMCK-g-PAA/PDMUP with FTIR, XPS, XRD, and SEM techniques provided evidence for semi-interpenetrating polymer networks (semi-IPNs) and component interactions. The prepared product exhibited excellent water absorbency (681.3 g/g) and enhanced the soil's water-retention capacity. Cumulative release of N, P, and K was 56.1%, 64.3%, and 74.1%, respectively, after 40 days–meeting a Committee of European Normalization (CEN) standard. Agricultural application of CMCK-g-PAA/PDMUP promoted wheat growth. Desirable water retention, slow-release properties, and wheat growth effects highlight the product's potential for improving agriculture. Unlabelled Image • Application of the polymer (CMCK-g-PAA/PDMUP) could achieve utilization of waste straw. • The CMCK-g-PAA/PDMUP is derived from waste straw and rich in fertilizers (N, P and K). • The product had excellent water retention and slow-release properties. • The product prepared by waste straw can reduces production cost and promote plant growth. [ABSTRACT FROM AUTHOR]

Hydrocarbons with four carbons in their molecular structure (C4s) represent an important chemical family in the modern petrochemical industry. Converting less valuable C4s into more valuable C4s with effective separation has been of significant industrial interest. The large variety of C4s leads to a complex reaction pathway network. Prior work carried out on C4 modelling and optimisation has been largely industry-focussed with limited studies found in academic publications. This work aims to bridge the research gap by developing a systematic methodology that can identify the optimal process pathways for maximum economic return. A superstructure network is developed, showing comprehensive pathways for C4 processing. Mathematical programming is applied to model the superstructure with individual processing units, in which simplified process models used in the network model can be supported by detailed process models. Optimisation is implemented in GAMS, the results of which help gain important physical insights into the best options for C4 processing. [ABSTRACT FROM AUTHOR]

• The onset and termination electric potential to form the steady cone-jet electrospray increase as conductivity increasing. • The lower and upper limitation of liquid flowrate to form the steady cone-jet electrospray decrease as conductivity increases. • The varicose instability can transform into whipping instability as the electrical conductivity increasing. • The jet breakup instability transition mechanism is interpreted by theoretical analysis. • The whipping to similar micro-dripping instability can be observed for EG with higher conductivity. In present work, the effect of the electrical conductivity on the steady cone-jet electrospray are experimentally investigated, where the operating diagram and the jet breakup instability are extensively examined. A hemispherical tube is employed as spraying nozzle severed as high electric potential electrode in a needle-plated electrode configuration compared to the common and sheathed tubes. The cone-jet electrospray is visualized by a high-resolution camera and extensively analyzed offline. The aqueous solution in ethanol, Diethyleneglycol (DEG) and Ethylene glycol (EG) are atomized with varied electrical conductivity under different high electric potentials and flowrates. Experimental results indicate that the cone-jet electrospray can operate in the certain ranges of operating parameter for all types of capillaries. The operating diagram for the hemispherical tube is significantly broader than other tubes because of various electric field strength distribution. The onset electric potential to determine a steady cone-jet electrospray gradually increases and the termination value also increases as the electrical conductivity increases. The lower and upper flowrate to form a steady cone-jet electrospray also increase as the electrical conductivity increases. The jet breakup instability can transit from varicose to whipping due to low the reference flow rate as electrical conductivity increases, which is agreement with theoretical analysis. In particular, for EG, the transition from whipping to similar micro-dripping is observed as the electrical conductivity increases, while the transition also occurs as flowrate increases for EG with higher electrical conductivity. The increase in the electrical conductivity and flowrate elongates the cone due to EHD body force, which causes the electric field varying, further resulting in the difference in jet breakup instability. Moreover, the electrical conductivity also plays an important role in jet breakup length. The instability variation of jet with conductivity (DEG), q V =1000 nL/s, ϕ =8.00 kV (Hemispherical nozzle with D o =0.70mm); The variation with liquid flow rate of EG with higher conductivity (K =8.5 × 10−4 s/m, ϕ =10.20 kV, (Hemispherical nozzle with D o =0.70mm) [Display omitted] [ABSTRACT FROM AUTHOR]

High-energy lithium-ion batteries (LIBs) have been actively pursued for practical applications in advanced electric vehicles and large-scale energy storage systems. The silicon (Si) material has been considered as a promising anode candidate due to its impressive lithium storage capacity, but is facing the challenge to ameliorate its cycling and rate performance. We here report a structure integration strategy to overcome major issues of poor capacity retention and slow kinetics during the lithium storage of Si anode, through in situ embedding Si nanoparticles into V 2 C MXene nanosheets. The MXene-supported Si@V 2 C nanocomposite anode reveals significantly enhanced cycling stability and improved lithium storage kinetics compared to that of the pristine Si anode. A high capacity exceeding to 430 mAh g−1 can be retained for 150 cycles at 200 mA g−1 current density. In addition, the conductive MXene supporter has been demonstrated to facilitate lithiation/delithiation processes for the Si by enhancing the charge transfer kinetics, as it is demonstrated by in situ electrochemical impedance spectroscopic (EIS) and Galvanostatic Intermittent Titration Technique (GITT) measurements. Findings from this work may inspire feasible structural designs for the practical deployment of MXene composited Si anode materials for next-generation lithium-ion batteries. [Display omitted] • Si@V 2 C composite anode was explored using V 2 C MXene as supporting substrate with enhanced Si stability performance. • A high capacity of 430 mAh g−1 can be retained for 150 cycles at 200 mA g−1 current density. • The V 2 C MXene can provide improved electronic conductivity and structural support of the Si anode during cycling. [ABSTRACT FROM AUTHOR]

Gaseous pollutants transport inside liquid micro-cylinders with internal circulations in an equilateral triangular configuration is simulated to study the effects of varied gap-ratio (1 ≤ G / R ≤ 4), Reynolds (Re) number (30 ≤ Re ≤ 160) and incident angle (α = 0° , 30° and 60°) on the absorption in a uniform gaseous stream. The shear stress fluctuates with spatial position on the interface due to unsteady flow separation and attachment. Furthermore, the 'primary' and 'secondary' vortexes inside liquid micro-cylinders are induced, respectively, where soluble gaseous pollutants are quickly entrained and partially blocked into liquid micro-cylinders by 'inflow' and 'outflow' type circulations pair at the stern regions, respectively. For incident angles α = 0 ° and α = 60 ° , the symmetric flow forms because of the symmetric configuration of liquid micro-cylinders, while for incident angle α = 30 ° , the asymmetric flow appears due to asymmetric arrangement. The 'primary' (large clockwise) and 'secondary' (small counterclockwise) vortexes usually depending on Re number and G / R facilitate gaseous pollutants intrusion into liquid micro-cylinders at separation point. The sensitivity of gap-ratio is presented based on the transient accumulation (m so 2 ′), which characterizes the exact influence of G / R. The larger gap-ratio facilitates faster saturation of sulfur dioxide inside liquid micro-cylinders because of fully developed internal vortexes. As R e number increasing, the gaseous pollutants transport could be significantly enhanced because internal vortexes become gradually stronger. In addition, the incident angle has no significant effect on pollutants transport inside liquid micro-cylinders because of slightly direct interaction between separated shear layers and wakes. [ABSTRACT FROM AUTHOR]

• The stable cone-jet occurs in a certain range of electric potential and flow rate. • The electrified meniscus forms appears successively convex, linear sides and concave with an increase in electric potential. • The jet breakup transits from varicose to kink instability with an increase in flow rate. The cone-jet is one of the most interesting means in electrohydrodynamic atomization (EHDA) for wide applications because of highly charged and monodisperse drops. The pulsating and stable cone-jet modes in EHDA of diethyleneglycol (DEG) are observed by means of high-speed photography technology, as well as the breakup modes transition of electrified jet from varicose to kink instability. The conductive liquid is driven to form a liquid cone at the outlet of the capillary tube, and form a permanent jet from the apex of the cone by the tangential electric stress. With an increase in electric potential, the cone angle and jet length increase. The electrified meniscus and the cone may appear convex, linear sides and concave in cone jet regime, which depends on the static equilibrium of forces exists at each point of electrified liquid surface. The jet breakup modes with multi-jet, varicose and kink instabilities are successively recorded as liquid flow rates increasing. The jet breakup transition depends on flow rate. The drops size rises proportionally with an increase in liquid flow rate or a decrease in electric potential in stable cone-jet mode. The dimensionless diameter d / d 0 as a function of the dimensionless flow rate q V / q m is in good agreement with the universal scaling laws. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to investigate the alterations of brain volumetry and associated structural covariance at lobar level in cerebral small-vessel disease (CSVD) with and without cognitive impairment.Method: Twenty-seven CSVD patients with mild cognitive impairment (CSVD-MCI), 37 CSVD patients with normal cognition (CSVD-NC), and 35 controls, underwent T1-weighted imaging of magnetic resonance. Volume of gray matter (GM) and white matter (WM) and a lobar atrophy index that measures the ratio of cerebrospinal fluid to brain parenchyma were quantified for each lobe. One-way ANOVA with multiple comparison corrections was performed to compare these volumetric measures. Volumetric structural covariance analyses were performed with lobar atrophy indexes to investigate the alterations of anatomical covariance within each pair of lobar regions in CSVD-NC and CSVD-MCI subjects compared with controls.Results: CSVD-NC subjects presented no significant volumetric differences with controls in any of the lobar regions. Compared with controls, CSVD-MCI patients presented significantly smaller volume of GM in bilateral frontal and parietal lobes, significantly smaller volume of WM in right cingulate lobe, and significantly larger lobar atrophy indexes of bilateral temporal, insular lobes and left cingulate lobe (P < 0.05). Both CSVD-NC group and CSVD-MCI group showed significant differences of structural covariance as measured by lobar atrophy index compared with controls. In particular, CSVD-MCI group showed even more extensive alterations of structural covariance, especially in bilateral cingulate and temporal lobes.Conclusions: There are alterations of brain volumetry and associated structural covariance within lobar regions in CSVD, which indicates the potential brain structural reorganization in CSVD. [ABSTRACT FROM AUTHOR]

Aminopeptidase N (APN) is an important ectopeptidase involved in many physiological functions e.g. tumor angiogenesis, and the detection of APN activity thus facilitates the early diagnosis and elucidation of tumor development. Herein we propose a one-pot and one-step colorimetric sensing method for detecting APN activity based on a peptide functionalized gold nanoparticles/cucurbit[8]uril (pep-AuNPs/CB[8]) supramolecular structure. In principle, a peptide that comprises both the recognition sequence of APN and binding motif of CB[8] is first functionalized onto the surface of AuNPs. Because CB[8] can interact with two binding motifs simultaneously, the assembly of pep-AuNPs and CB[8] consequently take place, leading to the formation of pep-AuNPs/CB[8] supramolecular structure. However, in the presence of APN, the peptide will be hydrolyzed by APN, resulting in the breach of binding motifs of CB[8] as well as the prevention of the formation of pep-AuNPs/CB[8] supramolecular structure. In this way, the activity of APN can be determined through the absorbance changes based on the assembly/disassembly of AuNPs. Under optimized conditions, the detection of APN activity is achieved in a linear range from 5 μg/mL to 15 μg/mL with a detection limit of 0.42 μg/mL, which is also available directly in serum samples. Because of the simplicity and the cost-efficient materials, the method is competent for practical applications. [ABSTRACT FROM AUTHOR]

α-MgAgSb is considered as a potential near-room-temperature thermoelectric material in virtue of its excellent electrical properties, ultralow lattice thermal conductivity and abundant constituent elements. However, it is hard to obtain high-quality phase pure α-MgAgSb due to its complex phase transition and high reactivity of element Mg, which cloaks material's intrinsic thermoelectric performance. Herein, through adopting a tantalum-sealing melting technique, we achieved highly-quality pure α-MgAgSb with large grain size and less oxygen content, as compared with our ball milled samples. The as-synthesized tantalum-sealing melted α-MgAgSb, without element doping or alloying, exhibited intrinsically low thermal conductivity, large weighted mobility, and high carrier concentration closes to the optimum range. Eventually, we attained a maximum thermoelectric figure of merit zT value of 1.3 at around 500 K in the tantalum-sealing melted α-MgAgSb. The average power factors and average zT values are also as high as 25 μW cm−1 K−2 and 1.1 respectively in the low-temperature range of (300 - 550) K, both of which rank as top values among the known materials. This study not only sheds new light on the understanding of intrinsic properties of α-MgAgSb but also demonstrates its great promise for harvesting low-grade waste heat. Record-high average power factor of 25 μW cm−1 K−2 and average zT of 1.1 were achieved in the melted α-MgAgSb sythesized by the tantalum-sealing melting technique. [Display omitted] [ABSTRACT FROM AUTHOR]

With the explosive economic development of China over the past few decades, air pollution has become a serious environmental problem and has attracted increasing global concern. Using satellite-based PM 2.5 data from 2000 to 2015, we found that the temporal-spatial variation of PM 2.5 in East China is characterized by high concentrations in the northern part and low concentrations in the southern part of East China, and by being seasonally high in autumn and winter but low in spring and summer. We also found that the regional average PM 2.5 concentration shows an approximative peak pattern over the last 16 years, with the highest, 60.13 μg m − 3 , and the lowest, 46.18 μg m − 3 , occurring in 2007 and 2000, respectively. Despite obviously diminishing heavy polluted regions with a PM 2.5 of > 80 μg m − 3 after 2011, those cells dominated by natural background have still not recovered back to the clean level of 2000. These characteristics are valuable information to analyze the relative contributions of anthropogenic emissions and atmospheric conditions to the temporal-spatial variation characteristics of PM 2.5 . [ABSTRACT FROM AUTHOR]

Abstract: The mixed-potential NOx sensor based on yttria-stabilized zirconia (YSZ) and oxide electrode is considered as a potential device used for the on-board diagnostics. Over the past decades, many researchers have paid their attentions on such YSZ based potentiometric NOx sensors and gotten a lot of achievement in developing new type electrode materials. Recently, in order to enhance the sensing performance of the mixed potential type NOx sensor, we have been focusing on modifying the triple-phase-boundary (TPB) by various techniques, including chemical corroding, the double-tape casting, the pore-forming and laser fabrication method. We also designed and prepared the microstructure of the oxide electrodes by controlling the sintering process for increasing the sensitivity of the NOx sensor. This paper reviews our works with regard to the above-mentioned two aspects. [Copyright &y& Elsevier]

Soil moisture (SM) is a fundamental environmental variable for characterizing climate, land surface and atmosphere. In recent years, several SM products have been developed based on remote sensing (RS), land surface model (LSM) or land data assimilation system (LDAS). However, little knowledge is available in understanding spatial patterns of the uncertainty of different SM products and potential regional drivers over the Qinghai-Tibet Plateau (QTP), a complex environment for accurate SM estimation. This paper investigates the sensitivity of the SM uncertainties based on the three-cornered hat (TCH) method and a generalized additive model (GAM) in terms of underlying surface characteristics (sand fraction, soil organic matter, vegetation, land surface temperature, and topography) and near-ground meteorology (precipitation and air temperature) in the third pole environment over the 2015–2018 period. Eleven SM products are involved in this work, including Soil Moisture Active Passive (SMAP), Soil Moisture Ocean Salinity INRA-CESBIO (SMOS-IC), Japan Aerospace Exploration Agency (JAXA), Land Surface Parameter Model (LPRM), Climate Change Initiative - Active/Combined (CCI_A/CCI_C), Global Land Data Assimilation System (GLDAS), European Centre for Medium-Range Weather Forecasts Interim reanalysis (ERA-Interim), Global Land Evaporation Amsterdam Model product a/b (GLEAM_a/GLEAM_b), and Random Forest Soil Moisture (RFSM). Results show that most of the SM products perform well across QTP, while SMOS-IC is strongly affected by radio-frequency interference in this region, JAXA has a relatively higher noise level over QTP, and LPRM has larger relative uncertainties (RUs) in the southeast of QTP. Nonlinear regression analysis demonstrates that variations of RUs in SMOS-IC and JAXA are driven by topography, while LPRM's are mainly controlled by vegetation. In addition, two groups of opposite (positive/negative) effects from topography and vegetation, topography and precipitation, and precipitation and land surface temperature affect the spatial variations of RUs in CCI_A, RFSM, and ERA-Interim, respectively. Meanwhile, more complex relationships are found between multiple surface factors and RUs of different products. In general, the underlying surface factors explain on average 39.41% and 28.34% of the variations in RS and LSM/LDAS SM RUs, respectively. Comparatively, the near-ground meteorology factors have a slightly larger effect on LSM/LDAS products than that on RS products. • Three-cornered hat (TCH) method is used to estimate the uncertainties in multisource soil moisture products over the Qinghai-Tibet Plateau. • Field measurements from three in-situ networks are adopted to evaluate the estimated TCH results. • A two-stage data detection method is utilized to quantify the spatial variations in SM uncertainties. [ABSTRACT FROM AUTHOR]

• Few studies have analyzed the utilization of millet straw as raw materials in the preparation of superabsorbent resin. • The product had excellent water absorbency and slow-release property. • The product prepared by millet straw not only reduces production cost, but also promote plant growth. • Application of the fertilizer could achieve the goal of straw return to soil. To enhance utilization of waste straw and improve fertilizer efficiency, a novel semi-interpenetrating polymer network fertilizer (MSP-g-AA/PVA-APP) synthesized from straw cellulose and linear polymer was prepared by solution polymerization. The ammonium polyphosphate (APP) was introduced to supply nitrogen and phosphorus nutrients. The prepared materials were characterized with scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffractometry (XRD) and thermogravimetric analysis (TGA). The water absorbency and slow-release behavior of MSP-g-AA/PVA-APP were also studied. The results indicated that MSP-g-AA/PVA-APP exhibited excellent water absorbency of 681.3 g/g in distilled water and enhanced the water retention capacity of soil. The cumulative N and P release rates of MSP-g-AA/PVA-APP were 55.1 % and 47.3 % after 30 days in soil, respectively. The effect of MSP-g-AA/PVA-APP on growth of wheat was studied, and the results show that the application products could facilitate the growth of wheat. It could be concluded that the product with water retention and slow-release property, being low costs and friendly to environment, had great potential for application in agricultural. [ABSTRACT FROM AUTHOR]

• The droplet formation in electric periodic dripping regime was visualized. • The oscillation of electrified meniscus was visualized and identified. • The characteristic frequency deceases with an increase in applied potential. • The amplitude increases as electric number increasing. The dynamics of droplets and oscillation of electrified meniscus at low flow rates in an external electric field were investigated. An electric field is created by nozzle-plated electrode. The evolution of droplet formation is recorded by a high-speed digital camera. Meanwhile, the time evolution of meniscus is also focused. The critical sizes of the droplet and liquid thread were used to characterize the dynamics of droplet formation and oscillation of the meniscus. The results showed that a droplet gradually originates from a hemispherical meniscus and changes from spherical to pear-shaped. A liquid thread connects the meniscus and primary droplet, and pinches off as time advances. The droplets diameter decreases as electric potential increasing and is dependent of capillary diameter, while usually independent of flow rates. The droplet limiting length decreases, while the liquid thread diameter increases as electric Bond number increasing. The period of detachment decreases with an increase in electric potential and strongly depends on flow rate. The meniscus usually oscillates when the primary droplet detaches. The oscillation frequency increases as electric field strength increasing and is substantially affected by flow rate. An approximate equation to predict the oscillation frequency was presented, where the electric potential was taken into account. The variation of the oscillation frequency is qualitatively good agreement with experimental work. The amplitude of oscillation (or displacement) is significantly affected by electric field and increases as electric Bond number increasing. [ABSTRACT FROM AUTHOR]

• A new operational model with ant-miner algorithm was proposed to predict the risk of forest fires in cloud-rich areas. • The performance of proposed model was compared with that of the national risk prediction model of China. • The proposed model was compared to other risk prediction models with two classical machine learning algorithms. • The ant-miner algorithm-based model was more effective and reliable. Annually, millions of hectares of forest lands around the world are destroyed by fires. To minimize the fire-caused losses, more studies on the risk prediction of forest fires need to be carried out. For predicting the risk of forest fires in cloud-rich areas (e.g., the southwest of China), the synergetic use of operational forecasting systems and remote sensing-based models is expected to have a consistent performance. Therefore, we proposed in this study a new model based on ant-miner algorithm which has a good capability of solving multivariable and non-linear problems in the synergetic modeling of multi-source data. Based on historical fire data during 2000–2018 in Chongqing city, its performance was tested, and then was compared with that of other three models (i.e., meteorological data-, Artificial Neural Network-, and Support Vector Machine-based models). Results showed that, without interference from human factors, the risk predictions of proposed model were more objective. And, its mined-rules were easier to understand and also portable across multiple GIS platforms. Moreover, the proposed model has a better performance at predicting risk levels (i.e., overall accuracy was 79.02% and Kappa coefficient was 0.678) and the spatial distribution of its predictions were more detailed. This research indicated that the ant-miner algorithm-based model was more effective and reliable, and it could be used for constructing the operational system of risk predictions for forest fires in cloud-rich areas. [ABSTRACT FROM AUTHOR]

As a primary air pollutant, fine particulate matter (PM 2.5) is increasingly attracting attention. Crowdsourcing observations based methods are thought to be the best solutions for identifying the spatio-temporal distribution of PM 2.5 in intra-urban areas. However, inconsistent timing in the collection of crowdsourced data has typically been ignored in previous studies. To address this issue, a temporally calibrated method (TCM) was introduced in this study. By interpolating TCM-estimated observations using the inverse distance weighted (IDW) method, variations of PM 2.5 concentrations across the urban areas of Changsha City were captured. The results demonstrate that TCM can efficiently resolve the inconsistent timing defects of raw crowdsourcing observations (R 2 was 0.73 and the RMSE was 7.65 μg/m3). Furthermore, PM 2.5 distributions developed using TCM-based interpolations are of a finer spatial scale than those developed from raw observations at crowdsourcing locations. With a lack of funds to build sufficient stationary monitoring sites, developing crowdsourcing observation-based technology is the most promising solution for revealing intra-urban PM 2.5 variations at a higher spatio-temporal- resolution. Image 1 • A temporal calibration method was introduced for crowdsourcing air quality data. • TCM can eliminate time inconsistence of original crowdsourcing based PM 2.5 concentrations. • Intra-urban variations of PM 2.5 concentrations were revealed by densely observation. • Crowdsourcing observation is effective for fine scale air quality mapping in urban area. [ABSTRACT FROM AUTHOR]