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The organic carbon (Corg) stored in seagrass meadows is globally significant and could be relevant in strategies to mitigate increasing CO2 concentration in the atmosphere. Most of that stored Corg is in the soils that underlie the seagrasses. We explored how seagrass and soil characteristics vary among seagrass meadows across the geographic range of turtlegrass (Thalassia testudinum) with a goal of illuminating the processes controlling soil organic carbon (Corg) storage spanning 23° of latitude. Seagrass abundance (percent cover, biomass, and canopy height) varied by over an order of magnitude across sites, and we found high variability in soil characteristics, with Corg ranging from 0.08 to 12.59% dry weight. Seagrass abundance was a good predictor of the Corg stocks in surficial soils, and the relative importance of seagrass-derived soil Corg increased as abundance increased. These relationships suggest that first-order estimates of surficial soil Corg stocks can be made by measuring seagrass abundance and applying a linear transfer function. The relative availability of the nutrients N and P to support plant growth was also correlated with soil Corg stocks. Stocks were lower at N-limited sites than at P-limited ones, but the importance of seagrass-derived organic matter to soil Corg stocks was not a function of nutrient limitation status. This finding seemed at odds with our observation that labile standard substrates decomposed more slowly at N-limited than at P-limited sites, since even though decomposition rates were 55% lower at N-limited sites, less Corg was accumulating in the soils. The dependence of Corg stocks and decomposition rates on nutrient availability suggests that eutrophication is likely to exert a strong influence on carbon storage in seagrass meadows.

New-type magnesium alloy with prominent solubility and mechanical property lays foundation for preparing fracturing part in petroleum extraction. Herein, Mg-xZn-Zr-SiC alloy is prepared with casting strategy. Electrochemical and compression tests are conducted to assess the feasibility as decomposable material. Morphology, composition, phase and distribution are characterized to investigate decomposition mechanism. Results indicate that floccule, substrate component and reticulate secondary phase are formed on as-prepared surface. Sample also acts out enhanced compression strength to maintain pressure and guarantee stability in dissolution process. Furthermore, as decomposition time and zinc content increase, couple corrosion intensifies, resulting in gradually enhanced decomposition rate. Rapid sample decomposition is mainly due to basal anode dissolution, micro particle exfoliation and poor decomposition resistance of corroding product. Such work shows profound significance in preparing new-type accessible alloy to ensure rapid dissolution of fracturing part and guarantee stable compression strength in oil-gas reservoir exploitation.

Aiming to elucidate the hydrogen absorption/desorption cycling properties of Mg-based alloys with in-situ formed Mg2Ni and LaHx (x = 2, 3) nanocrystallines, the hydrogen storage cycle stability, hydriding/dehydriding cycling kinetics and thermodynamic stability of the experimental alloys have been investigated in detail. The results show that the Mg–Ni–La alloys exhibit improved hydrogen storage cycling properties and can remain storage hydrogen above 5.5 wt% after 200 cycles. With the increase of cycling numbers, the dehydrogenation rates of the experimental samples increase firstly and then gradually decrease, and eventually maintain relative stable state. Microstructure observation reveals that powders sintering and hydrogen decrepitation both exist during hydrogen absorption/desorption cycles due to repeated volume expansion and contraction. Meanwhile, the in-situ formed LaHx (x = 2, 3) and Mg2Ni nanocrystallines stabilize the microstructures of the particles and hinder the powders sintering. After 200 cycles, the average particle size of the experimental samples decreases and the specific surface area apparently increases, which leads to the decomposition temperatures of MgH2 and Mg2NiH4 slightly shift to lower temperatures. Moreover, Mg2Ni and LaHx (x = 2, 3) have been proven to be stable catalysts during long-term cycling, which can still uniformly distribute within the powders after 200 cycles.

The methanol decomposition reaction has gained substantial attention due to the wide range of applications that its intermediates offer. In this work, methanol (CH3OH) decomposition on Copper-embedded graphene (CuG) surface has been investigated via density functional theory with Grimme-D2 dispersion correction. The charge density of the CuG surface has been analyzed and the redistribution of the electron density of the surface has been represented via the electron density difference (EDD) map. Moreover, the decomposition reaction mechanism of CH3OH on the CuG surface through the cleavage of C–H, O–H and C–O bonds has been investigated in detail. In the initial state, the C–O and O–H bonds of CH3OH have similar activation barriers, thereby the adsorption and degradation mechanism of the intermediate states arising through O–H bond cleavage on the CuG surface has been investigated. In addition, the charge density calculations of the transition state geometries have been conducted and examined with EDD maps. The results have revealed that the previously adsorbed oxygen molecule exhibited high catalytic activity towards O–H decomposition compared to the bare surface. The CuG surface has offered higher activity on the C–H bonds compared to the C–O bonds of the intermediate states generated by CH3OH decomposition. The results revealed that the proposed CuG structure can be utilized as an alternative electrode catalyst that can prevent the CO poisoning issue in direct methanol fuel cells. © 2021 Hydrogen Energy Publications LLC

Standing deadwood is an important structural component of forest ecosystems. Its occurrence and dynamics influence both carbon fluxes and the availability of habitats for many species. However, deadwood is greatly reduced in managed, and even in many currently unmanaged temperate forests in Europe. To date, few studies have examined how environmental factors, forest management and changing climate affect the availability of standing deadwood and its dynamics. Data from five periods of the Austrian National Forest Inventory (1981-2009) were used to (I) analyse standing deadwood volume in relation to living volume stock, elevation, eco-region, forest type, ownership and management intensity, (II) investigate the influence of forest ownership and management intensity on snag persistence and (III) define drivers of standing deadwood volume loss for seven tree genera (Abies, Alnus, Fagus, Larix, Picea, Pinus and Quercus) using tree-related, site-related and climate-related variables, and predict volume loss under two climate change scenarios. Standing deadwood volume was mainly determined by living volume stock and elevation, resulting in different distributions between eco-regions. While forest type and management intensity influenced standing deadwood volume only slightly, the latter exhibited a significant effect on persistence. Snag persistence was shorter in intensively managed forests than in extensively managed forests and shorter in private than in public forests. Standing deadwood volume loss was driven by a combination of diameter at breast height, elevation, as well as temperature, precipitation and relative humidity. Volume loss under climate change predictions revealed constant rates for moderate climate change (RCP2.6) by the end of the 21st century. Under severe climate change conditions (RCP8.5), volume loss increased for most tree genera, with Quercus, Alnus and Picea showing different predictions depending on the model used as the baseline scenario. We observed trends towards faster volume loss at higher temperatures and lower elevations and slower volume loss at high precipitation levels. The tree genera most susceptible to climate change were Pinus and Fagus, while Abies was least susceptible. Synthesis and applications. We recommend to protect standing dead trees from regular harvesting to ensure the full decomposition process. The consequences for decomposition-dependent species must be taken into account to evaluate the influences of management and climate change on standing deadwood dynamics., Journal of Applied Ecology, 60 (4), ISSN:0021-8901, ISSN:1365-2664

The core-shell metastable intermolecular composites (MIC) have attracted much attention in the past few years due to their unique properties. Here, the preparation of Al-Core heterojunction fibers using PVP as a template is proposed. The nano-Al was directly added to the precursor solution of cupric acetate monohydrate (CAM)/Polyvinylpyrrolidone (PVP), and the initial Al@CAM/PVP fibers were obtained via electrospinning. The core-shell MIC fibers are then obtained by calcining the initial fibers. The morphology, structure, and composition of Al-core MIC fibers were characterized, that the energetic fibers calcined at 300 °C, 350 °C, and 400 °C have a core-shell structure with shell compositions CuxO and PVP, CuxO and CuO, respectively. The energy release characteristics of Al-core MIC were investigated, and preliminary ignition tests were performed using an ignition temperature measuring instrument and a pulsed laser. The energetic fibers calcined at 300 °C exhibited unique properties. The decomposition of PVP in the shell layer promoted exotherm, and a low-temperature exothermic peak was shown at 372–458 °C. Lower ignition temperatures and higher flame heights were observed in the combustion tests than calcination at 350 °C and 400 °C. An unexpected result was that PVP can play a positive role in Al/CuO nanothermites. Simultaneously, this preparation method provided an idea for the integrated preparation of core-shell Al-Core MIC fibers and tuning the properties of MIC.

In space propulsion hydrogen peroxide is a “green” solution that overcomes the problem of toxicity related to hydrazine-based systems. This work aims at designing, developing, and characterizing a monopropellant thruster for small satellites, based on hydrogen peroxide. The engine is intended for use on a 12-Unit CubeSat in Low Earth Orbit. Based on mission requirements a catalytic chamber and a nozzle were designed and a ground-test breadboard was manufactured. The prototype was assembled and tested on ground and measured engine performances are discussed highlighting their dependence on the nozzle throat diameter, that primarily affects the chamber pressure. Finally, effects of the mass flow rate on the system reactivity and steady state conditions are also investigated.

This letter proposes a parallelizable algorithm for linear-quadratic model predictive control (MPC) problems with state and input constraints. The algorithm itself is based on a parallel MPC scheme that has originally been designed for systems with input constraints. In this context, one contribution of this letter is the construction of time-varying yet separable constraint margins ensuring recursive feasibility and asymptotic stability of sub-optimal parallel MPC in a general setting, which also includes state constraints. Moreover, it is shown how to tradeoff online run-time guarantees versus the conservatism that is introduced by the tightened state constraints. The corresponding performance of the proposed method as well as the cost of the recursive feasibility guarantees is analyzed in the context of controlling a large-scale mechatronic system. This is illustrated by numerical experiments for a large-scale control system with more than 100 states and 60 control inputs leading to run-times in the millisecond range.

A new NLO crystal of L-Arginine doped with potassium iodide were harvested from solution growth technique with slow evaporation method. Powder X-ray diffraction analysis exposes the structure. Presence of vibration functional groups in the grown crystal was confirmed by FTIR spectroscopy. Using the spectrum of UV–Vis-NIR the optical transmission and absorption spectra were studied. TGA-DSC studies reveal the decomposition and thermal stabilities of the grown crystals. Kurtz Perry Powder technique determines the second harmonic generation NLO behavior.

The iron and steel industries currently face the depletion of high-grade ore and high CO2 emissions. Some initiatives that effectively utilize alternative carbon sources and abundant low-grade ores become the preferable solutions. This novel study aims to utilize municipal solid waste (MSW) as a reducing agent in ironmaking using low-grade (goethite) ores. As an initial fundamental approach, the comparison of decomposition behaviors between the model and actual MSW was investigated in thermogravimetric analysis. Both model and actual MSWs mainly decompose at 300-500 degrees C. As for reduction tests, pellets containing MSWs and ores with different pretreatments were prepared. The pellets were reduced in an Ar atmosphere at different temperatures. The effect of different ores: high-grade and low-grade ones, on the decomposition of MSW and the iron reduction, were investigated. As a result, interestingly, the low-grade, goethite ore-containing pellet exhibits a more significant reduction degree than the high-grade ones. The reduction is completed in 5 minutes at 700 degrees C and above, indicating a significant reduction by the decomposed carbon. The reduction degree extends at elevated temperature, which reaches more than 94% at 900 degrees C.

Nitrogen oxides (NOx) gases, such as nitrous oxide (N2O), nitrogen oxide (NO), and nitrogen dioxide (NO2), are considered the most hazardous exhausts exhaled by industries and stationary and non-stationary application engines. Investigation of catalytic decomposition of NO has been carried out on copper ion exchanged with different bases, such as COK12, Nb2O5, Y-zeolite, and ZSM5. The catalytic decomposition of NO is widely accepted as an excellent method for the abatement of NO. However, the catalyst that achieves the highest reactivity in terms of NO decomposition is still a matter of research. The present paper aims to extend the research on the reactivity of non-noble metal-based catalysts using the direct decomposition method to remove NO from diesel engine exhaust. The reactivity of catalysts was observed in a quartz fixed bed reactor of 10 mm diameter placed in a furnace maintained at a temperature of 200 °C to 600 °C. The flow of NO was controlled by a mass flow controller, and the gas chromatography technique was used to observe the reactivity of the catalysts. Analysis showed that adding Cu to COK12, Nb2O5, Y-zeolite, and ZSM5 supports resulted in a rise in NO decomposition compared to stand-alone supports. Further experimental trials on the performance of Cu-ZSM5 at varying flow rates of NO showed that the NO decomposition activity of the catalyst was higher at lower flow rates of NO.

Biological decomposition and wildfire are two predominant and alternative processes that can mineralize organic C in forest litter. Currently, the relationships between decomposition and fire are still poorly understood. We provide an empirical test of the hypothesized decoupling of surface litter bed decomposability and flammability, and the underlying traits and trait spectra. We employed a 41-species set of gymnosperms of very broad evolutionary and geographic spread, because of the wide range of (absent to frequent) fire regimes they are associated with. We found that the interspecific pattern of mass loss proportions in a “common garden” decomposition experiment was not correlated with any of the flammability parameters and an RDA analysis also showed that the decomposability and flammability of leaf litter in litter layers were decoupled across species. This decoupling originates from the former depending mostly on size and shape spectrum traits and the latter on PES traits and those trait spectra being virtually uncorrelated. Synthesis: Our results show that, indeed, leaf litter decomposability and flammability parameters are decoupled across species, and this decoupling can be explained by their different drivers in terms of trait spectra: chemical traits for decomposability and size-shape traits for litter layer flammability.

We consider a Lévy process Y(t) that is not continuously observed, but rather inspected at Poisson( $\omega$ ) moments only, over an exponentially distributed time $T_\beta$ with parameter $\beta$ . The focus lies on the analysis of the distribution of the running maximum at such inspection moments up to $T_\beta$ , denoted by $Y_{\beta,\omega}$ . Our main result is a decomposition: we derive a remarkable distributional equality that contains $Y_{\beta,\omega}$ as well as the running maximum process $\bar Y(t)$ at the exponentially distributed times $T_\beta$ and $T_{\beta+\omega}$ . Concretely, $\overline{Y}(T_\beta)$ can be written as the sum of two independent random variables that are distributed as $Y_{\beta,\omega}$ and $\overline{Y}(T_{\beta+\omega})$ . The distribution of $Y_{\beta,\omega}$ can be identified more explicitly in the two special cases of a spectrally positive and a spectrally negative Lévy process. As an illustrative example of the potential of our results, we show how to determine the asymptotic behavior of the bankruptcy probability in the Cramér–Lundberg insurance risk model.

The plane exposure of support vitally affects the catalytic performance of the catalyst. In this work, CeO2 nanorods ((1 1 0) plane exposure), nano-octahedrons ((1 1 1) plane exposure) and nano-cubes ((1 0 0) plane exposure) were prepared as the supports of Pt/CeO2 samples to investigate the effect of CeO2 plane exposure on total toluene oxidation. Characterizations reveal that the (1 1 0) plane of CeO2 is more helpful to the dispersion of Pt species, followed by (1 1 1) face. The improved dispersion of Pt species can enhance the metal-supports interaction, which promotes the electron transfer of CeO2 carrier to Pt nanoparticles and the adsorption-activation of O2, thereby facilitating the total oxidation of toluene via the Langmuir–Hinshelwood (L-H) mechanism. Therefore, Pt/CeO2-r (nanorods) sample expresses the most excellent catalytic performance of toluene oxidation. Finally, the procedure of toluene total oxidation was studied by in-situ DRIFT. We expect that this work can contribute to the development of an effective sample for the decomposition of volatile organic compounds (VOCs).

The processes of decomposition that the body will have after the time of death are peculiar and complex. The body swells and expels gases and fluids, and the flesh decays. It also attracts many insects and scavengers. We know that these fluids are nutrients for the vegetation, and if the body is inhumed in the subsurface, they allow a rapid crop growth that remote sensors can mark. During forensic investigations, mapping the fluid migration in the subsurface can help reconstruct the genesis of a clandestine grave. Several studies show how different remote sensors and analyses can be sensitive to human burials. This paper presents a preliminary experiment studying the fluid dispersion in the subsurface using simulated body fluids in a shallow grave and detecting it through the ground penetrating radar (GPR) technique (given its ability to detect dielectric constant changes in the investigated media) and other remote sensing techniques. Although the simulation of the body fluids related to the dielectric constant was accurate and allowed us to better understand how decomposition in the subsurface does not always migrate in the way that was initially expected (toward gravity), other typical characteristics of the body fluids, other soils and external factors were left out and would be studied in future simulations.

Tensor decompositions, such as CANDECOMP/PARAFAC (CP), are widely used in a variety of applications, such as chemometrics, signal processing, and machine learning. A broadly used method for computing such decompositions relies on the Alternating Least Squares (ALS) algorithm. When the number of components is small, regardless of its implementation, ALS exhibits low arithmetic intensity, which severely hinders its performance and makes GPU offloading ineffective. We observe that, in practice, experts often have to compute multiple decompositions of the same tensor, each with a small number of components (typically fewer than 20), to ultimately find the best ones to use for the application at hand. In this article, we illustrate how multiple decompositions of the same tensor can be fused together at the algorithmic level to increase the arithmetic intensity. Therefore, it becomes possible to make efficient use of GPUs for further speedups; at the same time, the technique is compatible with many enhancements typically used in ALS, such as line search, extrapolation, and non-negativity constraints. We introduce the Concurrent ALS algorithm and library, which offers an interface to MATLAB, and a mechanism to effectively deal with the issue that decompositions complete at different times. Experimental results on artificial and real datasets demonstrate a shorter time to completion due to increased arithmetic intensity.

Polyoxymethylene dimethyl ether (PODEn, n ≥ 1) is a class of oxygenated fuels containing unique carbon-oxygen chain structure and a promising alternative fuel for diesel engines. In this study, low-temperature oxidation characteristics of PODE3 were studied experimentally and numerically. Experiments were performed in a jet-stirred reactor (JSR) at equivalence ratios of 0.5, 1.0 and 2.0, in the temperature range of 500 to 950 K, and at atmospheric pressure. Mole fractions of PODE3, O2, H2, CO, CO2, CH3OH and C1-C2 hydrocarbons were measured by gas chromatograph (GC). Experimental measurements were compared with the simulation results based on two literature low-temperature oxidation models, denoted as the He model and the Cai model, respectively. Good agreement was obtained between the measured and simulated fuel consumption profiles, while a deviation was observed between the experimental and simulation results on the mole fractions of O2 and intermediate products at medium temperatures. Reaction pathway analyses based on the two models were performed, revealing that the second O2-addition reaction pathway is more significant in the prediction by the Cai model than that by the He model. Sensitivity analyses pointed out that the most important reactions affecting fuel consumption are the H-abstraction reactions of PODE3, and the decomposition of H2O2 and the consumption of CH2O become more sensitive at medium temperatures.

No consensus has been reached on the role of reducible and irreducible supports on the reaction pathway of CO oxidation over supported metal catalysts. Here, colloidal ligand-free Pt nanoparticles were deposited on Al2O3 and CeO2 to investigate the support effect in CO oxidation by in situ diffuse reflectance Fourier-transform infrared spectroscopy (DRIFTS) and mass spectrometry (MS). On Pt/Al2O3, the carbonate-like intermediates accumulate and do not decompose to CO2 at the ignition temperature (150 °C) or above; the conversion of CO to CO2 follows classic Langmuir−Hinshelwood (L–H) mechanism with direct reaction of CO and O2 on Pt. Whereas for Pt/CeO2, the CO conversion to bidentate carbonate (b-CO32−) species followed by decomposition to CO2 is a main reaction pathway leading to its high reactivity at low temperature (75 °C). CeO2 facilitates the activation of oxygen to produce the carbonate-like intermediates and further decomposition to CO2, which resulted in a lower ignition temperature.

In a rapidly warming tundra, ecosystems will undergo major environmental changes that are predicted to significantly alter belowground processes such as decomposition of plant litter. Making use of International Tundra Experiment sites (ITEX), which were established approximately two decades ago, we examined the long-term impacts of warming on decomposition. We used the Tea Bag Index (TBI) methodology to measure the annual mass loss (%) of two tea types as a proxy for potential decomposition rates, across five tundra vegetation types. Direct effects of warming were assessed by comparing mass loss within and outside warming manipulations. Indirect effects of warming, such as those caused by warming-induced changes in plant community composition, were assessed through the relationship between mass loss of tea and local biotic and abiotic conditions. We found positive effects of warming on decomposition, although the responses varied between vegetation and tea types. Interestingly, we found support for the indirect influence of long-term warming on decomposition through warming-induced changes in the composition of plant communities. Our findings demonstrate the complexity in decomposition responses to warming across different vegetation types and highlight the importance of long-term legacies of warming in decomposition responses across the Arctic.

The cognition of active sites in the Ni-based catalysts plays a vital role and remains a huge challenge in improving catalytic performance of low temperature CO2 dry reforming of methane (LTDRM). In this work, typical catalysts of SiO2 and γ-Al2O3 supported Ni and Ni-Ce were designed and prepared. Importantly, the difference in the chemical speciations of active sites on the Ni-based catalysts is revealed by advanced characterizations and further estimates respective catalytic performance for LTDRM. Results show that larger [ Ni n 0 ] particles mixed with [Ni-O-Sin]) species on the Ni/SiO2(R) make CH4 excessive decomposition, leading to poor activity and stability. Once the Ce species is doped, however, superior activity (59.0% CH4 and 59.8% CO2 conversions), stability and high H2/CO ratio (0.96) at 600 °C can be achieved on the Ni-Ce/SiO2(R), in comparison with other catalysts and even reported studies. The improved performance can be ascribed to the formation of integral ( [ Ni n 0 ] -[CeIII-□-CeIII]) species on the Ni-Ce/SiO2(R) catalyst, containing highly dispersed [ Ni n 0 ] particles and rich oxygen vacancies, which can synergistically establish a new stable balance between gasification of carbon species and CO2 dissociation. With respect to Ni-Ce/γ-Al2O3(R), the Ni and Ce precursors are easily captured by extra-framework Aln-OH groups and further form stable isolated ( [ Ni n 0 ] -[Ni-O-Aln]) and [CeIII-O-Aln] species. In such a case, both of them preferentially accelerate CO2 adsorption and dissociation, causing more carbon deposition due to the disproportionation of superfluous CO product. This deep distinguishment of chemical speciations of active sites can guide us to further develop new efficient Ni-based catalysts for LTDRM in the future.

The fast decomposition of peroxides (M2O2, where M = H+, Li+) at room temperature has gained increased attention given its relevance, from propulsive systems to metal-O2 conversion batteries. This study describes, by a rational design of experiment, the influence of selected parameters such as: pH, initial concentration of K2CO3, precipitate aging, precipitate washing, and thermal treatment for the hydrotalcite co-precipitation, characterizing it for each synthesis variable. The results show that hydrotalcites can efficiently be converted in Co-Mn-Al spinels and as a result, a new highly active Co2Mn0.5Al0.5O4 spinel oxide was synthesized after thermal treatment. Its activity and mechanical resistance were tested in a micro-thruster reactor where it showed total decomposition (> 98%) of H2O2 and in a Li-O2 battery, with increased cyclability, been able to reduce the charging potential in ~200 mV. These encouraging results enhance the importance not only of this class of material, but also, the importance of robust synthesis methodologies for reproducible results.

In this study, several noble zeolites (SA-600A)-based catalysts supported with RuCl3.nH2O and LiOH·H2O materials were investigated for H2 production from NH3 decomposition. The synthetic catalysts were simultaneously prepared at different supported materials mixing ratios. The effect of initial mixing of Li and Ru on catalyst performance compared to simultaneous mixing was studied. All catalysts were tested for hydrogen production from NH3 decomposition at atmospheric pressure, temperature range of 200–670 oC, and gas hourly space velocity (GHSV) of 3000 h−1. It was found that the simultaneous and initial mixing of Li and Ru has the same NH3 decomposition results. The zeolite-based catalyst was enhanced with the Ru supported material mixing ratio increase. Among all the synthetic catalysts the catalyst type of 40 g (SA-600A)/5 g RuCl3.nH2O/3 g LiOH·H2O) showed the highest catalyst activity. The catalyst with a mixing ratio of 40 g (SA-600A)/5 g RuCl3.nH2O/3 g LiOH·H2O) was registered the peak NH3 conversion 99.87% at lower temperature of 490 °C.

The phosphorus-doped carbon materials as one of novel carbon catalysts towards the hydrogen evolution reaction (HER) have attracted considerable attention over the past years. However, the role of C-P species palyed in the HER activity is still not clear up to now. Phosphorus-doped carbon nanotubes (P-CNTs) were prepared by chemical vapor deposition and annealed at 900, 1000 and 1200 ℃ to remove all or parts of phosporus species, resulting in four samples with different proportions of graphite-, pyridine- and pyrrole-like P species. The correlations between their HER activity and the contents of three types of P species were investigated. Results showed that the content of graphite-like P decreased with the annealing temperature and no graphite-like P was retained at 1200℃. The HER activity increased with the annealing temperature and the one annealed at 1200 ℃ had the highest HER activity in an acid medium with an overpotential of 0.266 V at a current density of 10 mA/cm−2. Density functional theory calculations revealed that the pentagon- and nine-membered ring defects formed by the destruction of graphite-P species contributed mainly to the HER activity, which gave a deep insight into the active sites for HER.

Death is a common outcome of infection, but most disease models do not track hosts after death. Instead, these hosts disappear into a void. This assumption lacks critical realism, because dead hosts can alter host–pathogen dynamics. Here, we develop a theoretical framework of carbon-based models combining disease and ecosystem perspectives to investigate the consequences of feedbacks between living and dead hosts on disease dynamics and carbon cycling. Because autotrophs (i.e. plants and phytoplankton) are critical regulators of carbon cycling, we developed general model structures and parameter combinations to broadly reflect disease of autotrophic hosts across ecosystems. Analytical model solutions highlight the importance of disease–ecosystem coupling. For example, decomposition rates of dead hosts mediate pathogen spread, and carbon flux between live and dead biomass pools are sensitive to pathogen effects on host growth and death rates. Variation in dynamics arising from biologically realistic parameter combinations largely fell along a single gradient from slow to fast carbon turnover rates, and models predicted higher disease impacts in fast turnover systems (e.g. lakes and oceans) than slow turnover systems (e.g. boreal forests). Our results demonstrate that a unified framework, including the effects of pathogens on carbon cycling, provides novel hypotheses and insights at the nexus of disease and ecosystem ecology.

A systematic study has been carried out to investigate the neutron transmission signal as a function of sample temperature. In particular, the experimentally determined wavelength-dependent neutron attenuation spectra for a martensitic steel at temperatures ranging from 21 to 700°C are compared with simulated data. A theoretical description that includes the Debye–Waller factor in order to describe the temperature influence on the neutron cross sections was implemented in the nxsPlotter software and used for the simulations. The analysis of the attenuation coefficients at varying temperatures shows that the missing contributions due to elastic and inelastic scattering can be clearly distinguished: while the elastically scattered intensities decrease with higher temperatures, the inelastically scattered intensities increase, and the two can be separated from each other by analysing unique sharp features in the form of Bragg edges. This study presents the first systematic approach to quantify this effect and can serve as a basis , for example, to correct measurements taken during in situ heat treatments, in many cases being a prerequisite for obtaining quantifiable results.

The present paper explores the two components of the glass ceiling effect: promotion barriers for women to the executive sphere and a gender‐based differential in executive pay. The research setting is the British oil industry, which constitutes a male‐dominated sector. Analyzing both components separately, the results suggest that females are promoted more frequently to the executive ranks while they experience a pay bias compared to men. Thus, the analysis reveals that the glass ceiling is cracking in this gender‐imbalanced industry. Yet, pay discrimination still exists. However, within the narrow corridor of executives, the present study suggests that gender pay discrimination diminishes the higher one who climbs up the executive ladder. The latter finding raises the cynical question: How far up the hierarchy ladder does a woman need to climb to overcome gender‐based pay discrimination?

Reactor performance of bubbling fluidized bed (BFB) and turbulent fluidized bed (TFB) was carefully examined and systematically compared using catalytic ozone decomposition as a model reaction, based on a complete mapping of local flow structures and spatial distributions of ozone conversion and solids holdup. TFB clearly has a higher conversion and shows better reactor performance than BFB as a result of the vigorously turbulent flow and the relatively homogeneous gas–solids mixing in TEB. Besides, the intensive interaction between gas and solids in TFB leads to greater gas–solids contact efficiency of TFB over that of BFB. Due to gas bypassing and backmixing caused by bubbling behaviours and two-phase structure, BFB deviates significantly from a plug flow reactor and sometimes from a continuously stirred tank reactor. The flow structures essentially dictate the reactor performance in the low-velocity fluidized beds.

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link. This paper proposes an adaptive localized decision variable analysis approach under the decomposition-based framework to solve the large scale multi-objective and many objective optimization problems. Its main idea is to incorporate the guidance of reference vectors into the control variable analysis and optimize the decision variables using an adaptive strategy. Especially, in the control variable analysis, for each search direction, the convergence relevance degree of each decision variable is measured by a projection-based detection method. In the decision variable optimization, the grouped decision variables are optimized with an adaptive scalarization strategy, which is able to adaptively balance the convergence and diversity of the solutions in the objective space. The proposed algorithm is evaluated with a suite of test problems with 2-10 objectives and 200-1000 variables. Experimental results validate the effectiveness and efficiency of the proposed algorithm on the large scale multiobjective and many-objective optimization problems.

Phosphogypsum is a solid waste sourced from the wet-process phosphoric acid industry, which causes severe environmental damages. Its utilization was limited by its high decomposition temperature and high energy consumption. Herein, an Fe-P slag, which is a solid waste that mainly comprises iron phosphide (FeP) and diiron phosphide (Fe2P), can dramatically decrease the decomposition temperature of phosphogypsum. It was found that the Fe-P slag and CaSO4 can react as shown in the following reaction equation: 2Fe1.5P+3CaSO4+6CO2→Ca3(PO4)2+Fe3O4+3SO2+6CO. Its reaction mecha-nism was further determined using the thermodynamic method. It was found that CaS was the key intermediate for this reaction. The CaSO4 conversion for this method can reach approximately 97% under the optimized roasting conditions: the molar ratio between Fe1.5P and CaSO4 of 2:3, roasting temperature of 900 °C, a roasting time of 8 h.

The Goncourt Prize novel of Michel Houellebecq focuses on the parable of a fictional artist, Jed Martin, whose production ranges from photos of road maps to videos on manufactured products’ degradation, via portraits of people representing jobs. The Map and the Territory (2010) ends with a representation of the total triumph of vegetation in a future world museifing the first industrial age. One of the great questionings of aesthetic evaluation criteria is linked to the rise of popular literature, that some intellectuals considerate as a form of the death of art and individual creativity substituted with industrial production. Playing with the codes of detective story, Houellebecq describes his own death and his body transformation in an imitation of a Pollock painting; the crime results to be an attempt to cover up the theft of Michel Houellebecq, Writer, the portrait of the novelist that Jed Martin created to replace another canvas, Damien Hirst and Jeff Koons sharing the Art Market, that he destroyed. The contribution analyses the novel of Houellebecq as a reflection on contemporary art and literature that mix ekphrasis, mise en abyme and intertextuality to blend creation and decomposition and to question the possibility of representation.

In Bourlard and Kamp (Biol Cybern 59(4):291–294, 1998), it was theoretically proven that autoencoders (AE) with single hidden layer (previously called “auto-associative multilayer perceptrons”) were, in the best case, implementing singular value decomposition (SVD) Golub and Reinsch (Linear algebra, Singular value decomposition and least squares solutions, pp 134–151. Springer, 1971), equivalent to principal component analysis (PCA) Hotelling (Educ Psychol 24(6/7):417–441, 1993); Jolliffe (Principal component analysis, springer series in statistics, 2nd edn. Springer, New York ). That is, AE are able to derive the eigenvalues that represent the amount of variance covered by each component even with the presence of the nonlinear function (sigmoid-like, or any other nonlinear functions) present on their hidden units. Today, with the renewed interest in “deep neural networks” (DNN), multiple types of (deep) AE are being investigated as an alternative to manifold learning Cayton (Univ California San Diego Tech Rep 12(1–17):1, 2005) for conducting nonlinear feature extraction or fusion, each with its own specific (expected) properties. Many of those AE are currently being developed as powerful, nonlinear encoder–decoder models, or used to generate reduced and discriminant feature sets that are more amenable to different modeling and classification tasks. In this paper, we start by recalling and further clarifying the main conclusions of Bourlard and Kamp (Biol Cybern 59(4):291–294, 1998), supporting them by extensive empirical evidences, which were not possible to be provided previously (in 1988), due to the dataset and processing limitations. Upon full understanding of the underlying mechanisms, we show that it remains hard (although feasible) to go beyond the state-of-the-art PCA/SVD techniques for auto-association. Finally, we present a brief overview on different autoencoder models that are mainly in use today and discuss their rationale, relations and application areas.

Anthropogenic stressors are predicted to alter biodiversity and ecosystem functioning worldwide. However, scaling up from species to ecosystem responses poses a challenge, as species and functional groups can exhibit different capacities to adapt, acclimate, and compensate under changing environments. We used a naturally acidified seagrass ecosystem (the endemic Mediterranean Posidonia oceanica) as a model system to examine how ocean acidification (OA) modifies the community structure and functioning of plant detritivores, which play vital roles in the coastal nutrient cycling and food web dynamics. In seagrass beds associated with volcanic CO

In this work, six energetic complexes were prepared and used as promoters for the hypergolic reaction of 1-ethyl-3-methylimidazolium cyanoborohydride [EMIM][BH3CN] and 90% H2O2. The structures of these compounds were studied by FT-IR spectroscopy, powder XRD, and single crystal X-ray diffraction. The results revealed that all the compounds were iso-structural and each metal centre was coordinated with four organic ligands and two counter ions. The decomposition temperatures of these compounds ranged from 169.6-255.9 °C. After adding 10 wt.% of prepared complexes to an ionic liquid, [EMIM][BH3CN], the shortest ignition delay time achieved was 94 ms. Moreover, the formed homogenous catalytic fuels had similar densities, thermal stabilities, as well as specific impulses similar to that of pure [EMIM][BH3CN]. The simple preparation method, excellent yield, as well as high performance of these compounds make them promising promoters for use in green hypergolic bipropellants.

Exploring an alternative strategy with high efficiency and low cost to abate formaldehyde (HCHO) in indoor environment, is of increasing significance for people’s health. CeO2 catalysts prepared by hydrothermal, precipitation and calcination methods were investigated for HCHO removal at ambient temperature. It is found that indoor fluorescent light visibly boosts the catalytic performance of CeO2 catalysts for HCHO decomposition at ambient temperature. Among the CeO2 catalysts, CeO2 prepared from hydrothermal method (CeO2-H) exhibits a superior catalytic performance and an excellent durability by eight recycle times. Based on the characterization and analysis, the excellent catalytic performance of CeO2-H is mainly contributed by its abundance of surface oxygen vacancies, and photogenerated electrons and hole activated by fluorescent light. This work shows a potential practicability in HCHO pollution elimination by taking full advantage of the existing lighting in indoor environments.

The subgame perfect equilibrium in stationary strategies (SSPE) is the most important solution concept in applications of stochastic games, making it imperative to develop efficient methods to compute an SSPE. For this purpose, this paper develops an interior-point differentiable path-following method (IPM), which establishes a connection between an artificial logarithmic barrier game and the stochastic game of interest by adding a homotopy variable. IPM brings several advantages over the existing methods for stochastic games. On the one hand, IPM provides a bridge between differentiable path-following methods and interior-point methods and remedies several issues of an existing homotopy method called the stochastic linear tracing procedure (SLTP). First, the starting stationary strategy profile can be arbitrarily chosen. Second, IPM does not need switching between different systems of equations. Third, the use of a perturbation term makes IPM applicable to all stochastic games rather than generic games only. Moreover, a well-chosen transformation of variables reduces the number of equations and variables by roughly one half. Numerical results show that the proposed method is more than three times as efficient as SLTP. On the other hand, the stochastic game can be reformulated as a mixed complementarity problem and solved by the PATH solver. We employ the proposed IPM and the PATH solver to compute SSPEs. Numerical results evince that for some stochastic games the PATH solver may fail to find an SSPE, whereas IPM is successful in doing so for all stochastic games, which confirms the reliability and stability of the proposed method. Summary of Contribution: This paper incorporates the interior-point methods into a differentiable path-following method for computing stationary equilibria for stochastic games. This novel method brings excellent computational advantages and remedies several issues with the existing methods for stochastic games. We prove the global convergence of the proposed method and employ this method to solve numerous randomly generated stochastic games with different scales. Numerical results further confirm the high efficiency, stability, and universality of this method for stochastic games.

This study investigated catalytic decomposition and mass transfer of aqueous ozone promoted by Fe-Mn-Cu/γ-Al2O3 (Cat) in a rotating packed bed (RPB) for the first time. The results showed that the value of the overall decomposition rate constant of ozone (Kc) and overall volumetric mass transfer coefficient (KLa) are 4.28×10−3 s−1 and 11.60×10−3 s−1 respectively at an initial pH of 6, β of 40, C O 3 ( g ) of 60 mg·L−1 and QL of 85 L·h−1 in deionized water, respectively. Meanwhile, the Kc and KLa values of Fenhe water are 0.88×10−3 s−1 and 2.51×10−3 s−1 lower than deionized water, respectively. In addition, the Kc and KLa values in deionized water for the Cat/O3-RPB system are 44.86% and 47.41% higher than that for the Cat/O3-BR (bubbling reactor) system, respectively, indicating that the high gravity technology can facilitate the decomposition and mass transfer of ozone in heterogeneous catalytic ozonation and provide some insights into the industrial wastewater.

This paper presents a novel deep learning architecture for identifying outliers in the context of intelligent transportation systems. The use of a convolutional neural network with an efficient decomposition strategy is explored to find the anomalous behavior of urban traffic flow data. The urban traffic flow data set is decomposed into similar clusters, each containing homogeneous data. The convolutional neural network is used for each data cluster. In this way, different models are trained, each learned from highly correlated data. A merging strategy is finally used to fuse the results of the obtained models. To validate the performance of the proposed framework, intensive experiments were conducted on urban traffic flow data. The results show that our system outperforms the competition on several accuracy criteria.

The impacts of climate change on ecosystem structure and functioning are likely to be strongest at high latitudes due to the adaptation of biota to relatively low temperatures and nutrient levels. Soil warming is widely predicted to alter microbial, invertebrate, and plant communities, with cascading effects on ecosystem functioning, but this has largely been demonstrated over short-term (10 year) warming studies. Using a natural soil temperature gradient spanning 10-35°C, we examine responses of soil organisms, decomposition, nitrogen cycling, and plant biomass production to long-term warming. We find that decomposer organisms are surprisingly resistant to chronic warming, with no responses of bacteria, fungi, or their grazers to temperature (fungivorous nematodes being an exception). Soil organic matter content instead drives spatial variation in microorganism abundances and mineral N availability. The few temperature effects that appear are more focused: root biomass and abundance of root-feeding nematodes decrease, and nitrification increases with increasing soil temperature. Our results suggest that transient responses of decomposers and soil functioning to warming may stabilize over time following acclimation and/or adaptation, highlighting the need for long-term, ecosystem-scale studies that incorporate evolutionary responses to soil warming.

Journal of materials science & technology 102, 89 - 96 (2022). doi:10.1016/j.jmst.2021.06.041, In modern ��-solidified TiAl alloys, the decomposition of ��$_2$ phase is frequently observed during heat treatment or high-temperature deformation of the alloys. In this study, high-temperature deformation and decomposition mechanisms of ��$_2$ phase in a Ti-45Al-8.5Nb-0.2B-0.2W-0.02Y alloy are investigated. In a sample deformed at 800 ��C, the precipitation of ��$_o$(��$_o$) phase is observed within the equiaxed ��$_2$ phase. The nucleation of ��$_o$ particles within the ��$_o$ matrix indicates the ��$_2$ ��� ��$_o$ ��� ��$_o$ transformation. In addition, numerous �� phase precipitates form within the ��$_o$(��) areas. The ��$_2$ lamellae decompose into ultrafine (��$_2$+��) lamellae and coarsened �� lamellae via ��$_2$ ��� ��$_2$ + �� and ��$_2$ ��� �� transformation, respectively. Moreover, the ��$_o$ phase nucleates within the ultrafine lamellae via ��$_2$ ��� ��$_o$ transformation. However, in a sample deformed at 1000 ��C, the nucleation of ��$_o$ particles is sluggish, which is caused by the efficient release of the internal stress via dynamic recrystallization (DRX). These results indicate that complex phase transformations can be introduced by the decomposition of ��$_2$ phase in TiAl alloys with a high amount of ��-stabilizing elements., Published by Ed. Board, Journal of Materials Science & Technology, Shenyang

An effective strategy involving a suitable carrier is needed to improve the dispersion, combustion and catalytic performances of catalyst nanoparticles. Herein, a Bi2WO6/g-C3N4 composite employing g-C3N4 as the catalyst carrier was prepared by a one-step in situ hydrothermal method, which was used as the combustion catalyst of solid propellants. The catalyst’s structure, morphology and its catalytic decomposition of several energetic materials were characterized by a series of analyses. The optimal ratio of g-C3N4 and Bi2WO6 was systematically determined. The results demonstrate that Bi2WO6/g-C3N4 (4:6) composite can diminish the decomposition temperatures of ammonium perchlorate (AP), cyclotrimethylenetrinitramine (RDX), dihydroxylammonium 5,5'-bistetrazole-1,1'-diolate (TKX-50) and cyclotrimethylenetrinitramine+nitrocellulose (RDX+NC) by 25.0, 5.2, 24.0 and 1.2 (4.9) °C, and reduce their apparent activation energy by 59.5, 116.7, 11.6 kJ·mol-1, respectively. Moreover, the laser ignition tests indicate that Bi2WO6/g-C3N4 can effectively promote the ignition performance of RDX and RDX+NC. A possible mechanism of Bi2WO6/g-C3N4 on AP was proposed. The g-C3N4 catalyst carrier is superior to GO carrier due to its low cost, simple synthesis process, improved combustion and catalytic performances, as well as abundant N content. These make it have broad engineering application prospects in solid propulsion and several other energetic materials.

In recent years, MoS2 catalyzed/cocatalyzed Fenton/Fenton-like systems have attracted wide attention in the field of pollution control, but there are few studies on the effect of H2O2 feeding way on the whole Fenton process. Here, we report a new type of composite catalyst (MoS2-Fex) prepared in a simple way with highly dispersed iron to provide more active sites. MoS2-Fex was proved to possess selectivity for singlet oxygen (1O2) in effectively degrading sulfadiazine with a wide pH adaptability (4.0∼10.0). Importantly, the mechanism of the interaction between H2O2 and MoS2 on the Fenton reaction activity was revealed through the combination of experiment and density functional theory (DFT) calculations. Compared to the traditional “a large amount for one time” feeding way of H2O2, the “small amount for multiple times” of H2O2 feeding way can increase the degradation rate of sulfadiazine from 36.9% to 91.1% in the MoS2-Fex heterogeneous Fenton system. It is demonstrated that the “small amount for multiple times” of H2O2 feeding way can reduce the side reaction of decomposition of H2O2 by MoS2 and effectively improve the utilization rate of H2O2 and the stability of MoS2-Fex. Compared with Fe2O3-based Fenton system, MoS2-Fex can significantly save the amount of H2O2. Compared with nano-iron powder, the formation of iron sludge in MoS2-Fex system was significantly reduced. Furthermore, long-term degradation test showed that the MoS2-Fe75/H2O2 system could maintain the effectiveness of degrading organic pollutants for 10 days (or even longer). This study has a guiding significance for the large-scale treatment of industrial wastewater by improved Fenton technology in the future.

Post-mortem interval (PMI) information sources may be subject to varying degrees of reliability that could impact the level of confidence associated with PMI estimations in forensic taphonomy research and in the practice of medico-legal death investigation. This study aimed to assess the reliability of PMI information sources in a retrospective comparative analysis of 1813 cases of decomposition from the Allegheny County Office of the Medical Examiner in Pittsburgh, US (n = 1714), and the Crime Scene Investigation department at Southwest Forensics in the UK (n = 99). PMI information sources were subjected to a two-stage evaluation using an adapted version of the 3x5 aspects of the UK police National Intelligence Model (NIM) to determine the confidence level associated with each source. Normal distribution plots were created to show the distribution frequency of the dependent variables (decomposition stage and source evaluation) by the independent variable of PMI. The manner, location, and season of death were recorded to ascertain if these variables influenced the reliability of the PMI. A confidence matrix was then created to assess the overall reliability and provenance of each PMI information source. Reliable PMI sources (including forensic specialists, missing persons reports, and digital evidence) were used across extensive PMI ranges (1 to 2920 days in the US, and 1 to 240 days in the UK) but conferred a low incidence of use with forensic specialists providing a PMI estimation in only 35% of all homicide cases. Medium confidence PMI sources (e.g., last known social contact) accounted for the majority of UK (54%, n = 54) and US (82%, n = 1413) cases and were associated with shorter PMIs and natural causes of death. Low confidence PMI sources represented the lowest frequencies of UK and US cases and exclusively comprised PMI information from scene evidence. In 96% of all cases, only one PMI source was reported, meaning PMI source corroboration was overall very low (4%). This research has important application for studies using police reports of PMI information to validate PMI estimation models, and in the practice of medico-legal death investigation where it is recommended that i) the identified reliable PMI sources are sought ii) untested or unreliable PMI sources are substantiated with corroborating PMI information, iii) all PMI sources are reported with an associated degree of confidence that encapsulates the uncertainty of the originating source.

Formic acid is one of the key components in green chemistry being involved in energy storage, production of chemical intermediates and fuel components. Therefore the knowledge of its stability is of crucial importance and a systematic study of its decomposition is needed. The kinetics of formic acid decomposition to hydrogen and carbon dioxide was investigated in a laboratory-scale fixed bed reactor at 150–225 °C and atmospheric pressure. Palladium nanoparticles deposited on porous active carbon Sibunit were used as the heterogeneous catalyst. The catalyst was characterized by nitrogen physisorption and high-resolution transmission electron microscopy. The average palladium nanoparticle size was 5–6 nm. The impacts of mass transfer resistance and formic acid dimerization were negligible under the reaction conditions. Prolonged experiments revealed that the catalyst had a good stability. Hydrogen and carbon dioxide were the absolutely dominant reaction products, whereas the amounts of carbon monoxide and water were negligible. The experimental data were described with three kinetic models: first order kinetics, two-step adsorption-reaction model and multistep adsorption-decomposition model of formic acid. The multistep model gave the best description of the data.

Burning lignocellulosic biomass wastes in an outdoor atmosphere has placed heavy burden on ecological environment and increased risk on human health. Converting solid agricultural wastes into functional materials is a research hotspot. In this study, N-doped and CoO-loaded carbocatalyst (CoO-N/BC) was successfully synthesized from the cotton stalk biomass via a simple synthesis process of impregnation and carbonization. Compared with cotton stalk biomass derived pristine biochar, the CoO-N/BC possessed a higher specific surface area (466.631 m2 g-1 vs 286.684 m2 g-1) as well as a better catalytic performance in the activation of peroxymonosulfate (PMS) for CIP degradation. The superior catalytic efficiency was ascribed to the directional flow of electrons on the well-organized carbon network of CoO-N/BC, which accelerated electron migration and improved electron conduction ability. Based on the results of radical quenching experiment and electron paramagnetic resonance (EPR), both radical and non-radical process conjointly led to the stepwise decomposition of CIP, and singlet oxygen (1O2) mediated non-radical pathway was discovered to play a dominant role. Besides, the carbon-bridge mediated non-radical pathway was proved to accelerate this degradation process through the experiments of prolong the time of adding CIP at different time intervals. Nitrogen doped sites and CoO active sites as well as defects formed in sp2-hybridized carbon network were supposed to be the active sites for PMS. Furthermore, EIS and LSV were employed to confirm the electron transfer mediated non-radical process of reaction system. This work provides a modified strategy for the disposition of lignocellulosic biomass wastes and illuminates the underlying mechanism of heterogeneous catalysis by CoO-N/BC.

The evolutions of the phase composition, microstructure, and thermoelectric properties of BaFe4Sb12 materials at 773 K in vacuum were investigated to evaluate their long-term thermal stabilities. It was observed that the interior of the BaFe4Sb12 exhibited excellent thermal stability, while the surface decomposed into FeSb2, Sb, and Ba5Sb3. However, the decomposition rate sharply declined with increasing annealing time, and the thicknesses of the decomposition layer was approximately 49 μm after annealing for 30 days. Thermoelectric performances negligibly changed during the annealing process, and the dimensionless figure of merit remained in the range of 0.61 ± 0.02 at 800 K. The unique decomposition layer, wherein Ba5Sb3 compounds enriched in the outermost layer and along the FeSb2 grain boundaries, served as a dense protective cover to effectively retard the Sb sublimation, resulting in excellent long-term thermal stability. This work provides a plausible explanation for the long-term thermal stability of Fe4Sb12-based filled skutterudites.

Room-temperature Na-ion batteries have attracted great interest for over a decade owing to their natural abundance and similar intercalation chemistry with Li-ion. However, due to the uncontrolled decomposition of electrolyte and formation of solid electrolyte interphase, the large majority of sodium anode materials exhibit extremely low initial Coulombic efficiency and unsatisfactory cycling stability. Here we introduce a novel layered material, P2-Na0.547[Mg0.25Mn0.75]O2, as an SEI-free negative electrode. This material, delivers a reversible capacity of 126 mAh g−1 with a high initial Coulombic efficiency of 108%, and capacity retention of ∼ 80% after 1000 cycles at 4C rate. Pairing with Na3V2(PO4)3 cathode, excellent rate performance of ∼ 60% capability at 15C, and extra-high initial Coulombic efficiency of 97% are achieved, all attributed to the SEI-free feature of Na0.547[Mg0.25Mn0.75]O2. These results demonstrate the practical potential of our SEI-free anode material for high-power and long-life Na-ion batteries.

A field experiment was designed to determine the effect of mineralized nitrogen (N) through the decomposition of leafy biomass of agroforestry tree species as residues to underscore its uptake by maize under Sudan savannah conditions. The experiment was laid out as 3 x 4 x 2 factorial in a split-split plot design with three replicates for two cropping seasons. The factors considered include: control, biomass species (Albizia lebbeck and Parkia biglobosa) as main plots, four levels of nitrogen fertilizer (0, 40, 80, 120 kg N ha-1) as sub-plots, and two maize varieties (DMR-ESR-7 and 2009 EVAT) as sub-sub plots. Data were analysed using Analysis of Variance (ANOVA). Chemical composition of A. lebbeck biomass had higher average contents of N (32.4 g kg-1) and C (186.4 g kg-1) and lower average C: N ratio (57.5) than P. biglobosa and this affected their decomposition rates, hence, A. lebbeck decomposed faster than P. biglobosa. 56 % of N in the litter bags were released within the first 2 weeks of biomass incorporation and progressively increased up to 10 weeks after planting (WAP). Total N uptake by maize was lowest (2.8 kg N ha-1) in P. biglobosa and was highest (8.6 kg N ha-1) in A. lebbeck amended plots. It is then concluded that total N uptake by maize crop increased rapidly between 4-6 WAP, and the impact was obvious in plots amended with A. lebbeck biomass than in P. biglobosa plots during the two cropping seasons., Um experimento de campo foi projetado para determinar o efeito do nitrogênio mineralizado (N) através da decomposição da biomassa foliar de espécies de árvores agroflorestais como resíduos para destacar sua absorção pelo milho em condições de savana do Sudão. O experimento foi estabelecido como fatorial 3 x 4 x 2 em um delineamento de parcelas subdivididas com três repetições para duas safras. Os fatores considerados incluem: controle, espécies de biomassa (Albizia lebbeck e Parkia biglobosa) como parcelas principais, quatro níveis de fertilizante nitrogenado (0, 40, 80, 120 kg N ha-1) como subparcelas e duas variedades de milho (DMR -ESR-7 e EVAT 2009) como sub-subparcelas. Os dados foram analisados por meio de Análise de Variância (ANOVA). A composição química da biomassa de A. lebbeck apresentou maiores teores médios de N (32,4 g kg-1) e C (186,4 g kg-1) e menor relação C:N média (57,5) do que P. biglobosa e isso afetou suas taxas de decomposição, portanto, A. lebbeck se decompôs mais rápido que P. biglobosa. 56% do N nos sacos de lixo foram liberados nas primeiras 2 semanas de incorporação da biomassa e aumentaram progressivamente até 10 semanas após o plantio (WAP). A absorção total de N pelo milho foi menor (2,8 kg N ha-1) em P. biglobosa e maior (8,6 kg N ha-1) em parcelas corrigidas de A. lebbeck. Conclui-se então que a absorção total de N pela cultura do milho aumentou rapidamente entre 4-6 WAP, e o impacto foi óbvio em parcelas alteradas com biomassa de A. lebbeck do que em parcelas de P. biglobosa durante as duas safras.

Although the photovoltaic efficiency of organic solar cells (OSCs) has exceeded 17%, poor lifetime excludes OSCs from practical use. In particular, UV rays in sunlight may cause the decomposition o...

Considerable research efforts have been devoted to increase phosphorus (P) availability during aerobic composting. However, there is little discussion weather the dissolved organic carbon (DOC) controls the transformation among P-fractions. Thus, we investigated the changes in DOC compositions and P-fractions during biochar-amended composting (wet weight basis, 5% and 10%). TP content continuously increased since the ‘concentration effect’ during aerobic composting. NaHCO3-Pi, NaOH-Pi and HCl-Pi were main P-fractions, and biochar can improve P-bioavailability by transforming NaOH-Pi and HCl-Pi into NaHCO3-Pi. Structure equation models (SEMs) indicated that biochar enhanced the P-bioavailability through regulating the decomposition of DOC. Our results at least hint that the activation mechanism on P under the influence of DOC during biochar-amended composting.

CO2 hydrogenation to methanol was investigated over CuZnIn/MZrOx (M = La, Y or Ti) catalysts at 20 bar and at 225 °C with the purpose to elucidate the effects of the metal oxide promoter for ZrO2 and InOx for CuZnOx on reaction scheme of product formation, catalyst activity and product selectivity. Although the additives do not affect the overall scheme of product formation, they are relevant for the rates of direct CO2 conversion into methanol or CO and of methanol decomposition to CO and H2. This is due to their influence on dispersion of CuOx and the strength of basic sites for CO2 adsorption. Highly dispersed CuOx species are essential for CO2 conversion but not for methanol selectivity. The selectivity is improved over polymerized CuOx with strong basicity. This catalyst property can be controlled through promoting of (i) ZrO2 with La2O3/Y2O3 or (ii) CuZnOx with InOx. The latter promoter is crucial for hindering the undesired methanol decomposition to carbon monoxide.