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Using the regionally refined mesh (RRM) configuration of the US Department of Energy's Simple Cloud-Resolving Energy Exascale Earth System Model (E3SM) Atmosphere Model (SCREAM), we simulate and evaluate four meteorologically distinct atmospheric river events over California. We test five different RRM configurations, each differing in terms of the areal extent of the refined mesh and the resolution (ranging from 800 m to 3.25 km). We find that SCREAM RRM generally has a good representation of the AR-generated precipitation in CA, even for the control simulation which has a very small 3 km refined patch, and is able to capture the fine-scale regional distributions that are controlled largely by the fine-scale topography of the state. It is found that SCREAM generally has a wet bias over topography, most prominently over the Sierra Nevada mountain range, with a corresponding dry bias on the lee side. We find that refining the resolution beyond 3 km (specifically 1.6 km and 800 m) has virtually no benefit towards reducing systematic precipitation biases but that improvements can be found when increasing the areal extent of the upstream refined mesh. However, these improvements are relatively modest and only realized if the size of the refined mesh is expanded to the scale where employing RRM no longer achieves the substantial cost benefit it was intended for. [ABSTRACT FROM AUTHOR]

The spatial heterogeneity related to complex topography in California demands high-resolution (< 5 km) modeling, but global convection-permitting climate models are computationally too expensive to run multi-decadal simulations. We developed a 3.25 km California climate modeling framework by leveraging regional mesh refinement (CARRM) using the U.S. Department of Energy (DOE)'s global Simple Cloud-Resolving E3SM Atmosphere Model (SCREAM) version 0. Four 5-year time periods (2015–2020, 2029–2034, 2044–2049, and 2094–2099) were simulated by nudging CARRM outside California to 1° coupled simulation of E3SMv1 under the Shared Socioeconomic Pathways (SSP)5-8.5 future scenario. The 3.25 km grid spacing adds considerable value to the prediction of the California climate changes, including more realistic high temperatures in the Central Valley and much improved spatial distributions of precipitation and snowpack in the Sierra Nevada and coastal stratocumulus. Under the SSP5-8.5 scenario, CARRM simulation predicts widespread warming of 6–10 °C over most of California, a 38 % increase in statewide average 30 d winter–spring precipitation, a near-complete loss of the alpine snowpack, and a sharp reduction in shortwave cloud radiative forcing associated with marine stratocumulus by the end of the 21st century. We note a climatological wet precipitation bias for the CARRM and discuss possible reasons. We conclude that SCREAM RRM is a technically feasible and scientifically valid tool for climate simulations in regions of interest, providing an excellent bridge to global convection-permitting simulations. [ABSTRACT FROM AUTHOR]

As a major feature of tropical cyclones (TCs), controlling factors of TC outer size or size scaling remains a fundamental scientific question. The Rossby deformation radius and a natural extent associated with potential intensity have been proposed as two scalings of TC size. But neither of them satisfactorily captures the sensitivity of TC size to sea surface temperature (SST) in idealized f‐plane simulations. Inspired by the studies of the Hadley circulation, here we proposed a new TC scaling based on an energetic diagnostic scaling. TC size is primarily a ratio of the secondary circulation strength to subsidence velocity, further determined by the total atmospheric heating in the ascending area, the gross moist stability, the diabatic cooling, and the dry static stability. The former two is based on the moist energetic budget applied to the whole storm structure, while the latter two is based on the dry thermodynamic budget applied to the subsidence areas. The new scaling well captured the sensitivity of TC size to SST in idealized f‐plane simulations, partly resulted from expanded ascending area, increased surface moisture deficit, and weakened subsidence with increased SST. Plain Language Summary: Among the basic quantities of tropical cyclones (TCs), size is probably the most difficult to understand and predict. Due to lack of theories, our understanding of the controlling factors of TC size is rather limited. As a result, we have low confidence about the future change of TC size with warming. Idealized simulations have been used in recent years to study the environmental constraints of TC size, but the conventional scalings cannot capture the strong sensitivity of TC size to sea surface temperature (SST). In this study, we propose an energetic scaling that well predicts the simulated TC size variation with SST. We found that the secondary circulation strength and subsidence velocity essentially constrain the overall extent of TC. In addition, the framework also provides a new perspective to understand the limitation of conventional scalings. Key Points: A new energetic scaling successfully captures the outer size of tropical cyclone (TC) in f‐plane simulationsThe strong sensitivity of TC size to sea surface temperature (SST) depends on ascending area, surface moisture deficit, and subsidence velocityConventional TC size scalings underestimate or neglect the increases in inner‐core heating, which weaken their sensitivities to SST [ABSTRACT FROM AUTHOR]

A recent study noted reduced rainfall and cloud fraction over cold wakes induced by tropical cyclones, but a quantification of top‐of‐atmosphere (TOA) radiation change due to these cold wakes has not been attempted. Based on global TOA radiative flux observations, we show that TOA shortwave and longwave radiations increase by 0.76 W m−2 (0.2%) and 0.74 W m−2 (0.3%) over the cold wake area relative to local climatology, respectively. Due to the cancelation between the shortwave and longwave components, daily average TOA net radiation is only marginally modulated by cold wakes, but stands out in the day and night time average. In addition, the seasonal basin‐wide regulation of TOA net radiation by cold wakes can be up to 1.0 W m−2, locally comparable to the magnitude of radiative forcing due to man‐made aerosols. The regional impact of cold wakes on TOA radiations is therefore highly relevant and potentially important. Plain Language Summary: The upper ocean stirred by tropical cyclones leaves a cold wake at the surface. Though the impact of cold wakes on ocean heat pumping, heat transport, and storm intensity were extensively explored for years, only recently have their modulation effects on rainfall and clouds been demonstrated. A further question is whether cold wakes significantly modify the local and seasonal basin‐wide energy budget. Here, we show that in observations, the top‐of‐atmosphere (TOA) shortwave and longwave radiations can be modified over cold wakes by ∼0.7 W m−2, while the daily‐averaged net radiation is unremarkable due to the cancelation between the shortwave and longwave components. However, the modulation effect of cold wakes on the local net radiation in the daytime and nighttime is much larger than the daily‐averaged radiation. Moreover, the basin‐wide radiative effect is one order larger than the local effect. The regulation of TOA radiation by cold wakes, particularly for the regional impacts and diurnal cycles, is therefore highly suggested for future assessment of Earth's energy budget. Key Points: Local average top‐of‐atmosphere (TOA) longwave and shortwave radiations can be modulated by tropical cyclone cold wakes by ∼0.7 W m−2TOA net radiation change over cold wakes is small due to the cancelation between longwave and shortwave radiationsImpact of cold wakes on TOA net radiation differs over different basins due to different climatological mean radiations [ABSTRACT FROM AUTHOR]

A recent study noted reduced rainfall and cloud fraction over cold wakes induced by tropical cyclones, but a quantification of top‐of‐atmosphere (TOA) radiation change due to these cold wakes has not been attempted. Based on global TOA radiative flux observations, we show that TOA shortwave and longwave radiations increase by 0.76 W m−2 (0.2%) and 0.74 W m−2 (0.3%) over the cold wake area relative to local climatology, respectively. Due to the cancelation between the shortwave and longwave components, daily average TOA net radiation is only marginally modulated by cold wakes, but stands out in the day and night time average. In addition, the seasonal basin‐wide regulation of TOA net radiation by cold wakes can be up to 1.0 W m−2, locally comparable to the magnitude of radiative forcing due to man‐made aerosols. The regional impact of cold wakes on TOA radiations is therefore highly relevant and potentially important. Plain Language Summary: The upper ocean stirred by tropical cyclones leaves a cold wake at the surface. Though the impact of cold wakes on ocean heat pumping, heat transport, and storm intensity were extensively explored for years, only recently have their modulation effects on rainfall and clouds been demonstrated. A further question is whether cold wakes significantly modify the local and seasonal basin‐wide energy budget. Here, we show that in observations, the top‐of‐atmosphere (TOA) shortwave and longwave radiations can be modified over cold wakes by ∼0.7 W m−2, while the daily‐averaged net radiation is unremarkable due to the cancelation between the shortwave and longwave components. However, the modulation effect of cold wakes on the local net radiation in the daytime and nighttime is much larger than the daily‐averaged radiation. Moreover, the basin‐wide radiative effect is one order larger than the local effect. The regulation of TOA radiation by cold wakes, particularly for the regional impacts and diurnal cycles, is therefore highly suggested for future assessment of Earth's energy budget. Key Points: Local average top‐of‐atmosphere (TOA) longwave and shortwave radiations can be modulated by tropical cyclone cold wakes by ∼0.7 W m−2TOA net radiation change over cold wakes is small due to the cancelation between longwave and shortwave radiationsImpact of cold wakes on TOA net radiation differs over different basins due to different climatological mean radiations [ABSTRACT FROM AUTHOR]

Carbon-based materials have been well demonstrated to significantly improve biohydrogen (bioH 2) and biomethane (bioCH 4) production. However, the use of the same material for two-phase anaerobic digestion requires further investigation. In this study, three calcium-doped magnetic biochars (Ca-MBCs) with Fe2+ (0.01, 0.05 and 0.1 mol/L) and calcium lignosulphonate (CL) were prepared to promote H 2 and CH 4 yields. Material characterization revealed that the specific surface area was significantly increased and Fe ions were successfully attached to the BCs. All three Ca -MBCs can effectively raise H 2 yield, especially Ca-MBC2 (0.05 mol/L Fe2+), and the highest H 2 yield of 1050 mL was obtained. Under optimal conditions, the cumulative H 2 (37 °C, pH 6.0) and CH 4 yields (37 °C, pH 7.0) were 948 mL and 1599 mL, respectively, which were 64.9% and 40.8% higher than those of the control group. Ca-MBC2 promoted the activity of butyric acid fermentative bacteria at the H 2 evolution phase, raising the relative abundance of Clostridium ; At the methanogenisis phase, the content of coenzyme F420 was increased, and Ca-MBC2 could change the methanogens dominant strain, strengthen the dominant strain position of Methanolinea , and raise the relative abundances of H 2 - and acetic acid-trophic strains of Methanoregula , Methanosaeta , and Methanosarcina. [Display omitted] • Ca-MBCs were synthesized, containing CaCO 3 , Fe 3 O 4 and biochar (BC). • Ca-MBCs could release Ca and Fe ions in two-phase anaerobic process. • Ca-MBCs enriched bacteria and enhanced the activity of coenzyme F420. • H 2 and CH 4 yields increased by 64.9% and 40.8% at 300 mg/L of Ca-MBC2. • Ca-MBCs could be recycled by magnetic separation after two-phase digestion. [ABSTRACT FROM AUTHOR]

Manganese doped magnetic carbon (MDMC) was synthesized to enhance bio-hydrogen (H 2) process under the mesophilic and thermophilic conditions. MDMC characterization showed that MnFe 2 O 4 , Fe 2 O 3 and few MnCO 3 were adhered to activated carbon and formed MDMC whose specific surface area and average pore size were 110.92 m2·g−1 and 3.2 nm, respectively. Suitable concentration of MDMC promoted while high dosage suppressed the H 2 production of glucose through anaerobic fermentation by heat-treated sludge. The highest yields of 211 and 148 ml H 2 /g glucose were obtained at 400 mg/L (37 °C) and 600 mg/L MDMC (55 °C), being 55.8% and 19.3% higher than that of the control groups, respectively. Some possible mechanisms were proposed as follows: appropriate concentration of MDMC provided considerable and favorable sites for microbial colonization, released trace elements (e.g. Mn, Fe) into liquid for the microbial growth, and promoted the direct inter-species electron transfer. Moreover, MDMC could be recycled by magnetic separation after bio-H 2 process due to its magnetism. MnFe 2 O 4 , Fe 2 O 3 and few MnCO 3 were adhered to activated carbon, fabricating the manganese doped magnetic carbon (MDMC) that was employed to stimulate bio- hydrogen (H 2) production. Results showed that suitable amount of MDMC increased H 2 yield through providing a composite carrier and trace elements like Fe and Mn for H 2 production bacteria. MDMC could be also recycled via magnetic separation after the bio-process due to its magnetism. Image 1 • MDMC was synthesized, containing MnFe 2 O 4 , Fe 2 O 3 , MnCO 3 and AC. • Suitable addition of MDMC obtained the highest H 2 yield in bio-H 2 process. • The H 2 yields amended with MDMCs increased by 9.6–55.8 %. • MDMC enriched bacteria and promoted their growths and H+ transfer rates. • MDMC could be recycled by magnetic separation after bio-H 2 production. [ABSTRACT FROM AUTHOR]

Mixing of the upper ocean by the wind field associated with tropical cyclones (TCs) creates observable cold wakes in sea surface temperature and may potentially influence ocean heat uptake. The relationship between cold wake size and storm size, however, has yet to be explored. Here we apply two objective methods to observed daily sea surface temperature data to quantify the size of TC‐induced cold wakes. The obtained cold wake sizes agree well with the TC sizes estimated from the QuikSCAT‐R wind field database with a correlation coefficient of 0.51 and 0.59, respectively. Furthermore, our new estimate of the total cooling that incorporates the variations in the cold wake size provides improved estimates of TC power dissipation and TC‐induced ocean heat uptake. This study thus highlights the importance of cold wake size in evaluating the climatological effects of TCs. Plain Language Summary: The wind field of a tropical cyclone can mix warm water downward, leaving a cold wake at the surface. This effect may influence ocean heat uptake within the climate system. We derive a novel oceanic metric of tropical cyclone size based on its induced cold wake using sea surface temperature data for a period from 2002 to 2011. The cold wake size agrees well with the wind field size determined from QuikSCAT surface winds. Furthermore, with the cold wake size incorporated, total cooling provides better quantifications of tropical cyclone power dissipation and cyclone‐induced ocean heat uptake. More reliable estimates of cyclone power dissipation and sea surface cooling may be useful for both understanding and forecasting impacts of tropical cyclones on the climate system. Key Points: The size of the tropical cyclone wind field correlates reasonably well with the size of its mixing‐induced cold wakeWith the cold wake size incorporated, TC‐induced sea surface total cooling has a better correspondence with TC power dissipationCompared to sea surface cooling with a fixed cold wake area, the total cooling provides an improved estimate of TC‐induced ocean heat uptake [ABSTRACT FROM AUTHOR]

Widespread air pollutions, such as black carbon over East Asia in recent years, could induce a localized diabatic heating, and thus lead to localized static stability and meridional temperature gradient (MTG) changes. Although effect of static stability and MTG on eddies has been addressed by the linear baroclinic instability theory, impacts of a localized heating on mid-latitude eddy activities have not been well explored and quantified. Via a series of idealized global Held-Suarez simulations with different magnitudes of localized heating at different altitudes and latitudes, responses of mid-latitude eddy activity and circulation to these temperature perturbations are systematically investigated. Climatologically, the localized heating in the lower atmosphere induces a wave-like response of eddy activity near the mid-latitude jet stream. Over the heating region, eddy activity tends to be weakening due to the increased static stability. However, there are cyclonic anomalies over the upstream and downstream of the heating region. The zonal mean eddy activity weakens along the baroclinic zone due to reduced MTG and increased static stability. Furthermore, the response of eddy activity increased as the heating magnitude is increased and moved to higher altitudes. The influence of the heating decreases as the heating is prescribed further away from the climatological mid-latitude jet. This implies that the localized heating is most effective over the region with the maximum baroclinicity. Besides, enhanced storm track downstream of the localized heating area found here suggests that increased aerosols over East Asia might strengthen the North Pacific storm track. [ABSTRACT FROM AUTHOR]

[Display omitted] • CHA was produced to enhance HBu/HAc-DF pathway for more H 2. • H 2 evolution via dark fermentation (DF) raised by 35.27% with CHA. • CHA acted as an electron shuttle to facilitate electron transfer. • Ca2+ and Fe2+ ions were released from CHA to stimulate microbial activity. • CHA could promote the expression of functional genes from DF. For low yield in dark fermentation (DF), in this study, the carbonized humic acid (CHA) was produced and added to DF for enhancing biohydrogen (bioH 2) yield at mesophilic condition. The highest bioH 2 yield was 151.08 mL/g glucose with the addition of CHA at 80 mg/L, which was 35.27% and 16.53% higher than those of 0 mg/L CHA and 80 mg/L mineral humic acid (MHA) groups, respectively. Electrons preferentially conducted via the butyrate pathway due to CHA amendments, which corresponded to the prediction of relevant functional genes. Furthermore, CHA possessed distinctive advantages over MHA, which acted as an electron shuttle to facilitate electron transfer, released metal ions as an essential signal mediator and favored the reduction of ferredoxin, obtaining more H 2. The use of CHA in the field of H 2 -DF depicted the high-value utilization and industrial chain extension of MHA. [ABSTRACT FROM AUTHOR]

[Display omitted] • Molten salt carbonization is a reasonable way to obtain biochar (BC). • BioH 2 yield was enhanced by 32.4% with molten salt-modified BC (MSBC). • Mineral elements contained in MSBC contributed to biomass accumulation. • MSBC improved the electrochemical activity of anaerobic sludge. • Clostridium sensu stricto 1 and Citrobacter were enriched by MSBC. Generally, dark fermentation (DF) of hydrogen (H 2) synthesis has low H 2 production from industrial-scale plants. In this study, campus greening wastes-ginkgo leaves were used to produce molten salt-modified biochar (MSBC) and nitrogen (N 2)-atmosphere BC (NBC) in molten salt and N 2 environment at 800 °C, respectively. MSBC showed excellent properties including high specific surface area and electron transfer ability. After supplementation with MSBC, H 2 yield rose by 32.4% compared to the control group without carbon material. Electrochemical analysis revealed MSBC improved the electrochemical properties of sludge. Furthermore, MSBC optimized the microbial community structure and increased the relative abundance of dominant microbes, thus promoting H 2 production. This work provides a deep understanding of two carbons that play vital roles in increasing microbial biomass, supplementing trace element and favoring electron transfer in DF reactions. Salt recovery achieved 93.57% in molten salt carbonization, which has sustainability compared with N 2 -atmosphere pyrolysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrothermal carbon was used as an additive to enhance dark fermentation. • 600 mg/L Fe-HCM addition enhanced biohydrogen yield by 59%. • HCM and Fe-HCM enhanced the butyric acid-based fermentation pathway. • HCM and Fe-HCM raised the abundance level of Firmicutes from 35% to 41% and 56%. Dark fermentation (DF) for hydrogen (H 2) evolution is often limited to industrial application due to its low H 2 yield. In this work, hydrothermal carbon microspheres (HCM) and iron modified HCM (Fe-HCM) were prepared by hydrothermal process using waste corn cob. Subsequently, HCM and Fe-HCM were used in DF for more H 2. The highest H 2 yields amended with HCM and Fe-HCM at 600 mg/L were achieved to be 119 and 154 mL/g glucose (0.87 and 1.2 mol H 2 /mol glucose), respectively, being 24% and 59% higher than that of control yield. Soluble metabolites revealed HCM and Fe-HCM promoted butyric acid-based DF. Microbial composition depicted that HCM and Fe-HCM improved the abundance level of Firmicutes from 35% to 41% and 56%, while the abundance level of Clostridium_sensu_stricto_1 rose from 25% to 38% and 51%, respectively. This provides valuable guidance for hydrothermal carbon used in biofuel production. [ABSTRACT FROM AUTHOR]

Carbon-based materials such as graphite, graphene, biochar, activated carbon, carbon cloth and nano-tube, and maghemite and magnetite carbons are capable for adsorbing chemicals onto their surfaces. Currently, this review is to highlight the relevance of carbons in enhancing hydrogen or methane production. Some key roles of carbons in improving cell growth, enrichment and activity, and accelerating their co-metabolisms were elaborated with regard to their effects on syntrophic communities, interspecies electron transfer, buffering capacity, biogas upgrading, and fertilizer nutrient retention and land application. Carbons can serve as a habitation for microbial immobilization, and a provision for bioelectrical connections among cells, and provide some essential elements for anaerobes. Besides, an outlook on the possible options towards the large scale and improvement solutions has been provided. Further studies in this area could be encouraged to intend and operate continuous mode by designing carbon-amended bioreactor with stability and reliability. [ABSTRACT FROM AUTHOR]

Hydrogen (H 2 ) gas represents renewable resource candidate to traditional energy resource. Methods to promote the H 2 evolution rate attract increasing attentions. In the present research, ferric oxide/carbon nanoparticles (FOCNPs) were synthesized and evaluated the feasibility to enhance the production rate of H 2 gas from glucose through anaerobic fermentation by mixed bacteria. The results demonstrated that appropriate dose of FOCNPs promoted, while excessive concentration of FOCNPs suppressed the production of H 2 . Addition of 200 mg/L FOCNPs resulted in the highest yield of 218.63 ml H 2 /g glucose, 33.7% higher than 163 ml H 2 /g glucose of the control test without addition of FOCNPs. However, 400 mg/L of FOCNPs inhibited the H 2 evolution to 154 ml/g glucose, 5.5% lower than the control. It was revealed that the H 2 evolution followed the acetic pathways. The FOCNPs had a specific surface area of 27.63 m 2 /g, and thus addition of FOCNPs could provide more attachment sites for the growth of anaerobes. Moreover, FOCNPs could promote the activity of hydrogenase and electron transfer efficiency, beneficial for the bio-H 2 evolution. However, excessive addition of FOCNPs could be toxic to microbes, and further suppressing the H 2 production. The present research provided an effective method to promote the evolution rate of H 2 gas. [ABSTRACT FROM AUTHOR]

Effects of biochar (BC) and ferrous iron (Fe 2+ ) additions on hydrogen (H 2 ) production from glucose were investigated using batch experiment. The glucose with both BC and Fe 2+ additions were incubated at 37 °C for H 2 production. As compared with the control group (without BC and Fe 2+ additions), the synergic effects of BC and Fe 2+ make the lag phase time decease from 4.25 to 2.12 h, and H 2 yield increase from 158.0 to 234.4 ml/g glucose. Moreover, suitable concentrations of BC and Fe 2+ serve to enhance volatile fatty acid generation during H 2 evolution. These results indicate that H 2 production is improved by BC and Fe 2+ regulations, where synergic mechanisms are described as follows: BC acts as support carriers of anaerobes and system pH buffers, which promotes the biofilm formation and maintains suitable pH environment; Appropriate Fe 2+ concentration can improve hydrogenase activity in H 2 production. [ABSTRACT FROM AUTHOR]

Cephalosporin residue (CR) was used to produce biochar (BC) and activated carbon (AC) at 600 °C (BC600 and AC600). To compare the removal behaviors and mechanisms of Cr(VI) by CR and derived chars, batch adsorption tests were performed in Cr(VI) microenvironment like pH, Cr(VI) concentration, adsorbent dosage, combing with the characterization of adsorbents before and after adsorption. Fourier transform-infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), and Brunauer-Emmett-Teller (BET) techniques were used. Results showed that the Cr(VI) removals by CR and CR-chars fitted Freundlich and Langmuir models. Based on the Langmuir model, the maximum adsorption capacities of CR, BC600 and AC600 towards Cr(VI) were 107.41, 88.19 and 74.07 mg g −1 , respectively. The CR rich in dissolved carbon (DOC), –NH 2 and –COOH, chiefly acted as chelating and reducing agents, while the AC600 with high surface area mainly supported Cr(VI) adsorption during Cr(VI) removal process. [ABSTRACT FROM AUTHOR]

Waste reuse and renewable energy generation are encouraged in many countries. Anaerobic digestion of sewage sludge is usually limited by the slow hydrolysis rate of the sludge. To resolve the problem the lime mud was used in this biomethane production. Batch tests were performed at 55 °C with lime mud concentrations ranging from 1.25 to 5.00 g/L. The results showed that the highest methane yield per gram of volatile solid and volatile solid reduction were 146 ml and 42.4% at lime mud concentration of 2.50 g/L, which were 1.77 and 3.01 times higher than that of the control tests without lime mud, respectively. However, high levels of lime mud reduced the amount of available substrate and inhibited the anaerobes, thereby decreasing the methane production. The modified Gompertz model showed a better fit for the results than the first-order model. It was also found that the eco-friendly treatment of two types of solid waste had the potential to synergistically contribute to waste reuse and energy recovery. [ABSTRACT FROM AUTHOR]

This paper investigated the utilization of calcined-red mud (CRM) pretreatment to enhance fermentative hydrogen yields from brewers’ spent grain (BSG). The BSG samples were treated with different concentrations (0.0–20 g/L) of CRM at 55 °C for 48 h, before the biohydrogen process with heat-treated anaerobic sludge inoculum. The highest specific hydrogen production of 198.62 ml/g-VS was obtained from the BSG treated with 10 g/L CRM, with the corresponding lag time of 10.60 h. Hydrogen yield increments increased by 67.74%, compared to the control tests without CRM. The results demonstrated that the CRM could hydrolyze more cellulose and further provided adequate broth and suitable pH value for efficient fermentative hydrogen. The model-based analysis showed that the modified Gompertz model presented a better fit for the experimental data than the first-order model. [ABSTRACT FROM AUTHOR]

The limitations of the existing means of treating brewers' spent grain and sewage sludge highlight the need to find sustainable routes to manage them. Biochars derived from their mixtures enriching with magnesium and phosphorus, through pyrolysis at 400–700 °C, were characterized, and their potential use as a capture agent for ammonia-nitrogen removal in aqueous solutions was also analyzed. The yield increased with rising brewers' spent grain ratio, but decreased with increasing temperature. Higher pyrolysis temperature caused higher ash content, pH, surface basicity, specific surface area, and mineral element concentrations, whereas lower surface acidity, cation exchange capacity and nitrogen contents. Biochars derived from the mixtures of brewers' spent grain and sewage sludge (80:20, wt%) gained the highest removal efficiencies of ammonia-nitrogen, owing to their high surface area, magnesium and phosphorus availability, suitable surface chemistry and morphology. Compared with other biochars for ammonia-nitrogen adsorption, the biocahrs had high removal efficiencies (above 60%), which also had the potential to sustainably contribute to carbon dioxide emission reduction and nitrogen recovery. [ABSTRACT FROM AUTHOR]

This study investigated the use of calcined-lime mud from papermaking process (CLMP) pretreatment to improve fermentative hydrogen yields from corn-bran residue (CBR). CBR samples were pretreated with different concentrations (0–15 g/L) of CLMP at 55 °C for 48 h, prior to the thermophilic fermentation with heat-treated anaerobic sludge inoculum. The maximum hydrogen yield (MHY) of 338.91 ml/g-VS was produced from the CBR pretreated with 10 g/L CLMP, with the corresponding lag-phase time of 8.24 h. Hydrogen yield increments increased from 27.76% to 48.07%, compared to the control. The CLMP hydrolyzed more cellulose, which provided adequate substrates for hydrogen production. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of decentralized safety control (DSC) of constrained interconnected nonlinear safety-critical systems under reinforcement learning strategies, where asymmetric input constraints and security constraints are considered. To begin with, improved performance functions associated with the actuator estimates for each auxiliary subsystem are constructed. Then, the decentralized control problem with security constraints and asymmetric input constraints is transformed into an equivalent decentralized control problem with asymmetric input constraints using the barrier function. This approach ensures that safety-critical systems operate and learn optimal DSC policies within their safe global domains. Then, the optimal control strategy is shown to ensure that the entire system is uniformly ultimately bounded (UUB). In addition, all signals in the closed-loop auxiliary subsystem, based on Lyapunov theory, are uniformly ultimately bounded, and the effectiveness of the designed method is verified by practical simulation. [ABSTRACT FROM AUTHOR]

Lime mud from papermaking process (LMP) is a solid waste originated from the causticization process. Due to fine particle size and high alkalinity of LMP, its recovery is expensive and adverse effect is still uncertain. This review presents several current techniques proposed for LMP utilization in order to minimize its toxic effect on the environment. Conventional uses such as soil amendments, landfill and building materials are continually conducted. Recently, novel utilization of LMP to immobilize and remove pollutants in different phases (liquid, solid and gas) has provided new opportunities for efficient removal of dye, organics, heavy metals, carbon dioxide and sulfur dioxide. Moreover, as an additive summarized in this review, LMP can enhance the performance of biological process for treating organic waste, and its available value would be potentially improved further. [ABSTRACT FROM AUTHOR]

In this paper, the safe optimal control method for continuous-time (CT) nonlinear safety-critical systems with asymmetric input constraints and unmatched disturbances based on the adaptive dynamic programming (ADP) is investigated. Initially, a new non-quadratic form function is implemented to effectively handle the asymmetric input constraints. Subsequently, the safe optimal control problem is transformed into a two-player zero-sum game (ZSG) problem to suppress the influence of unmatched disturbances, and a new Hamilton–Jacobi–Isaacs (HJI) equation is introduced by integrating the control barrier function (CBF) with the cost function to penalize unsafe behavior. Moreover, a damping factor is embedded in the CBF to balance safety and optimality. To obtain a safe optimal controller, only one critic neural network (CNN) is utilized to tackle the complex HJI equation, leading to a decreased computational load in contrast to the utilization of the conventional actor–critic network. Then, the system state and the parameters of the CNN are uniformly ultimately bounded (UUB) through the application of the Lyapunov stability method. Lastly, two examples are presented to confirm the efficacy of the presented approach. [ABSTRACT FROM AUTHOR]

The effects of lime mud from papermaking process (LMP) addition as buffer agent and inorganic nutrient on the anaerobic digestion stability of food waste (FW) were investigated under mesophilic conditions with the aim of avoiding volatile fatty acids accumulation, and inorganic elements deficiency. When LMP concentration ranged from 6.0 to 10 g/L, the FW anaerobic digestion could maintain efficient and stable state. These advantages are attributed to the existence of Ca, Na, Mg, K, Fe, and alkaline substances that favor the methanogenic process. The highest CH 4 yield of 272.8 mL/g-VS was obtained at LMP and VS concentrations of 10.0 and 19.8 g/L, respectively, with the corresponding lag-phase time of 3.84 d and final pH of 8.4. The methanogens from residue digestates mainly consisted of Methanobrevibacter, coccus-type and sarcina-type methanogens with LMP addition compared to Methanobacteria in control. However, higher concentration of LMP inhibited methanogenic activities and methane production. [ABSTRACT FROM AUTHOR]

Abstract: Hydrogen production via anaerobic fermentation may suffer from instability or inhibition due to volatile fatty acids concentrations and inorganic elements deviations from optimality. A slight addition of white mud from ammonia–soda process (WMA) to the fermentation may show a feasible implement approach to use as buffer and inorganic nutrient. Batch tests were conducted to study the effect of the WMA addition on the hydrogen fermentation of food waste (FW) for the purpose of the maximum hydrogen yield (MHY) while achieving process stability and microbial germination through the endogenous alkalinity and inorganic elements of WMA. This was attributed to the existence of calcium, sodium, magnesium, potassium and alkali-rich materials, like calcium carbonate. 3 g of WMA addition to 200 g FW and fermentation time of 36 h resulted in obtaining the MHY of 145.4 mL H2/g VS, with a corresponding lag-phase time of 3.0 h. Under these operating conditions, the fermentation process demonstrated one of the highest measured stability with final pH 5.3. [Copyright &y& Elsevier]

Abstract: The effect of lime mud from paper-making process (LMP) addition on the H2 fermentation of food waste (FW) was investigated. It was found that a slight addition of LMP (1.0–4.0 g in 200 g FW) significantly enhanced the H2 fermentation performance, not only increasing the total amount of H2 produced but also accelerating the whole reaction, shortening the lag period, and increasing the H2 production rate. Fermentation stability and microbial germination were also facilitated by LMP addition. This was attributed to the existence of Ca, Fe, Mn and alkaline substances such as CaCO3 and NaOH. The batch process treating a mixture of FW and LMP was showed that the highest hydrogen production of 137.6 mL H2/g VS was achieved at final pH 5.0, adding 3 g LMP (in 200 g FW) to the fermentation process, which lag-phase time was about 2.5 h. [Copyright &y& Elsevier]

[Display omitted] • CoAl 0.2 Fe 1.8 O 4 and CoCu 0.2 Fe 1.8 O 4 NPs were synthesized to raise bioH 2 yield. • Humic acids were reduced by addition of CoAl 0.2 Fe 1.8 O 4 or CoCu 0.2 Fe 1.8 O 4 NPs. • CoAl 0.2 Fe 1.8 O 4 acted on cell membrane while CoCu 0.2 Fe 1.8 O 4 acted on EPS. • CoCu 0.2 Fe 1.8 O 4 obtained Clostridium_sensu_stricto_1 more than CoAl 0.2 Fe 1.8 O 4. • CoCu 0.2 Fe 1.8 O 4 NPs improved H 2 yield more than CoAl 0.2 Fe 1.8 O 4 NPs. Two various materials, copper and aluminum doped cobalt ferrite nanoparticles (NPs) were fabricated for investigating their effects of addition amounts on hydrogen (H 2) synthesis and process stability. CoCu 0.2 Fe 1.8 O 4 NPs enhanced H 2 production more than CoAl 0.2 Fe 1.8 O 4 NPs under same condition. The highest H 2 yield of 212.25 ml/g glucose was found at optimal dosage of 300 mg/L CoCu 0.2 Fe 1.8 O 4 NPs, revealing the increases of 43.17% and 6.67% compared with the control without NPs and 300 mg/L CoAl 0.2 Fe 1.8 O 4 NPs groups, respectively. NPs level of more than 400 mg/L inhibited H 2 generation. Further investigations illustrated that CoCu 0.2 Fe 1.8 O 4 NPs were mainly distributed on extracellular polymer substance while CoAl 0.2 Fe 1.8 O 4 NPs were mostly enriched on cell membrane, which facilitated electron transfer behavior. Community structure composition demonstrated that CoCu 0.2 Fe 1.8 O 4 and CoAl 0.2 Fe 1.8 O 4 separately caused a 9.67% and 9.03% increase in Clostridium sensu stricto 1 compared with the control reactor without NPs exposure. [ABSTRACT FROM AUTHOR]

In this work, the cobalt ferrate nanoparticles were prepared by a sol-gel method for investigating their influence on hydrogen production from dark fermentation. A moderate amounts (0.1–0.4 g/L) of these nanoparticles effectively enhanced the fermentation process. The highest hydrogen yield of 205.24 mL/g glucose was achieved at a dosing level of 0.4 g/L, which was a 31.8% enhancement compared to the control, while excess (0.5 g/L) nanoparticles decreased the hydrogen production by 9.7% compared to the control group. The mechanism analysis exhibited that the nanoparticles could either attach to the microbial surface or enter the cell interior without destroying the cell integrity, which promoted the electron transfer to anaerobes and stimulated the activities of hydrogen-producing enzymes such as enzymes and coenzymes. The microbial community revealed that a moderate amount of cobalt ferrate nanoparticles increased the abundance of Clostridium sensu stricto 1 from 14.49% to 18.84%, which was dominant and favored the sustainable conversion of glucose wastewater into clean hydrogen. [Display omitted] • Cobalt ferrate nanoparticles (CoFe 2 O 4 NPs) were synthesized to increase H 2 yield. • BioH 2 production was enhanced by 31.8% with 0.4 g/L CoFe 2 O 4 NPs. • CoFe 2 O 4 NPs changed the type of fermentation to butyric acid fermentation. • CoFe 2 O 4 NPs promoted microbial activity by acting on the microbial interface. • CoFe 2 O 4 NPs improved the abundance of Clostridium_sensu_stricto_1. [ABSTRACT FROM AUTHOR]

[Display omitted] • BioH 2 production was enhanced by supplementing with NiFe 2 O 4 NPs. • NiFe 2 O 4 NPs promoted mesophilic fermentation more than thermophilic process. • Bacterial activity was improved by Fe and Ni ions from corrosion of NiFe 2 O 4 NPs. • Clostridium butyricum were selectively enriched in the presence of NiFe 2 O 4 NPs. • Butyrate-type fermentation dominated bioH 2 production added with NiFe 2 O 4 NPs. In this work, nickel ferrite nanoparticles (NiFe 2 O 4 NPs) was prepared to improve hydrogen (H 2) production by dark fermentation. Moderate amounts (50–200 mg/L) promoted H 2 generation, while excess NiFe 2 O 4 NPs (over 400 mg/L) lowered H 2 productivity. The highest H 2 yields of 222 and 130 mL/g glucose were obtained in the 100 mg/L (37 °C) and 200 mg/L NiFe 2 O 4 NPs (55 °C) groups, respectively, and the values were 38.6% and 28.3% higher than those in the control groups (37 °C and 55 °C). Soluble metabolites showed that NiFe 2 O 4 NPs enhanced the butyrate pathway, corresponding to the increased abundance of Clostridium butyricum in mesophilic fermentation. The endocytosis of NiFe 2 O 4 NPs indicated that the released iron and nickel favored ferredoxin and hydrogenase synthesis and activity and that NiFe 2 O 4 NPs could act as carriers in intracellular electron transfer. The NPs also optimized microbial community structure and increased the levels of extracellular polymeric substances, leading to increased H 2 production. [ABSTRACT FROM AUTHOR]

To solve the thermodynamic limitations on the hydrogen (H 2) yield by dark fermentation (DF), the conductive carbons are usually used to mediate the H 2 -DF. In this work, the nitrogen (N)-phosphorus (N) doped starch carbon (NPSC) was prepared and characterized to investigate its influence on H 2 -DF. NPSC effectively raise H 2 yield compared with starch-derived carbon (SC). The optimal dosage of SC (400 mg/L) and NPSC (600 mg/L) caused the highest H 2 yield of 219.5 and 261.2 mL/g glucose, respectively, being higher than the control yield (161.4 mL/g glucose). Factually, compared with the control group without any carbon, NPSC optimized the microbial community structure and increased the abundance of C. butyricum from 19.09% to 30.87%. This fact increased the shift of metabolic pathway to butyric acid evolution, thereby promoting the substrate conversion level to H 2. [Display omitted] • Nitrogen and phosphorus doped starch carbon (NPSC) promoted electron transfer. • Optimal dosage of starch-derived carbon (SC) and NPSC were 400 and 600 mg/L. • NPSC enriched Clostridium butyricum more efficient than SC and control groups. • Metabolism analysis revealed NPSC raised the microbial activity in H 2 evolution. • The highest H 2 yields of SC and NPSC groups were 219.5 and 261.2 mL/g glucose. [ABSTRACT FROM AUTHOR]

Tropical cyclones (TCs) are an important source of turbulent mixing for the upper ocean at low latitudes, causing sea surface cooling and subsurface warming. A new estimate of annually accumulated sea surface cooling and upper ocean diapycnal diffusivity induced by TCs is obtained by using quantified cold wake sizes, which were largely ignored by previous studies. Both the annually accumulated tropical cyclone‐induced sea surface cooling and upper ocean diffusivity on a global scale show a significant decreasing trend over the period of 1982–2016, at a rate of −0.09 ± 0.03 °C/decade and −0.03 ± 0.01 cm2/s/decade respectively. The strengthening of ocean stratification with global warming contributes to the decrease of sea surface cooling and mixing, while the changes of tropical cyclone characteristics (such as translation speed, intensity, number, lifetime and size) contribute differently in various ocean basins. Plain Language Summary: The strong winds of tropical cyclones (TCs) greatly enhance upper ocean mixing. Cold water is mixed upwards, leaving cold wakes at the sea surface. Previous studies used cooling of the ocean surface induced by TCs to infer the upper ocean mixing, but some of their assumptions could lead to biases. In this study, based on quantified cold wakes, a new estimate of the sea surface cooling and upper ocean mixing induced by TCs is proposed. Based on observations, for the first time, we noted that the accumulated sea surface cooling and upper ocean mixing induced by global TCs have a significant decreasing trend over 1982–2016. This is primarily related to a more stable upper ocean and the decrease of tropical cyclone cold wake sizes with global warming. Key Points: With quantified cold wake size, a new estimate of sea surface cooling and upper ocean mixing induced by tropical cyclones is providedGlobal tropical cyclone‐induced annually accumulated ocean cooling and mixing have been decreasing in recent decadesThe increased ocean stratification and the decreased cold wake sizes contribute to the decrease of accumulated ocean cooling and mixing [ABSTRACT FROM AUTHOR]

The use of carbon composites and trace elements in biogas production has been demonstrated as an efficient approach. However, the relationship between carbon materials and the microbial community needs further clarification. In this study, a novel nickel-doped magnetic carbon material was produced to compare its role in biohydrogen (bioH 2) production under mesophilic (37 °C) and thermophilic (55 °C) conditions. Material characterization showed that NiFe 2 O 4 and Ni(OH) 2 were well doped into the activated carbon without obviously reducing its specific surface area. A moderate amount (200–600 mg/L) of magnetic carbon boosted bioH 2 production, while excess magnetic carbon inhibited bioH 2 evolution. The highest H 2 yields of 260 and 192 mL/g glucose were found at 600 mg/L (37 °C) and 800 mg/L magnetic carbon (55 °C), which were 46.9% and 60.0% higher than the control yields, respectively. The microbial community revealed that such magnetic carbon significantly increased the abundance of Clostridium sensu stricto 1 (57.91%) in the mesophilic process, and Clostridium sensu stricto 7 (24.29%), 8 (7.39%) and 10 (24.85%) were the dominant bacteria in thermophilic fermentation. The results also showed that the production of clean energy with a higher yield of H 2 and a low cost of production was achieved at 37 °C compared with those at 55 °C. Image 1 • Nickel-doped magnetic carbon (NDMC) was produced to improve bioH 2 evolution. • NDMC exhibited better properties than activated carbon in H 2 fermentation. • NDMC played different roles in mesophilic and thermophilic H 2 production. • NDMC selected Clostridium sensu stricto 1 as the dominant bacteria at 37 °C. • The highest H 2 yield of 260 mL/g glucose was obtained at 37 °C. [ABSTRACT FROM AUTHOR]

As efforts to close crop production yield gaps increase, the need has emerged to identify cost-effective strategies to reduce yield losses through soil improvement. Maize (Zea mays L.) production in coastal saline soil is limited by high salinity and high pH, and a limited number of soil amendment options are available. We performed a field experiment in 2015 and 2016 to evaluate the ability of combined flue gas desulfurization gypsum and furfural residue application (CA) to reduce the maize yield gap and improve soil properties. We carried out the same amendment treatments (CA and no amendment as a control) under moderate (electrical conductivity (EC1:1) ≈ 4 dS m−1) and high (EC1:1 ≈ 6 dS m−1) salinity levels. Averaged over all salinity levels and years, maize yields increased from 32.6% of yield potential in the control to 44.2% with the CA treatments. Post-harvest CA treatment increased the calcium (Ca2+) and soil organic carbon (SOC) contents while decreasing the sodium (Na+) content and pH in the upper soil layer. Corresponding nitrogen, phosphorus, potassium, calcium, and magnesium accumulations in maize were significantly increased, and Na accumulation was decreased in the CA group compared with the control. The economic return associated with CA treatment increased by 215 $ ha−1 at the high salinity level compared with the control, but decreased at the moderate salinity level because of the minor increase in yield. The results of this study provide insight into the reduction of yield gaps by addressing soil constraints. [ABSTRACT FROM AUTHOR]

Certain minerals possess structures that convey properties which improve soil quality; however, their application in coastal saline areas has been poorly studied. In this study, we explored the effects of combining mineral amendments on the improvement of wheat yield and soil properties in a two-year field experiment in mildly saline coastal soil areas of the Yellow River Delta, China. Five mineral materials were combined into the following four treatments: zeolite + rock phosphate (ZP), zeolite + silica calcium soil conditioner (ZC), vermiculite + rock phosphate (VP), and vermiculite + medical stone (VS). For all treatments, combined mineral amendments increased wheat yield compared to the control, with similar increases in yield following treatment with VP (45.7%), ZP (43.5%), and ZC (43.6%), and a significantly smaller increase following VS treatment (26.3%). These increases in grain yield were attributed to larger dry matter accumulation and higher grain numbers per ha. Compared to the control, ZP and ZC application substantially reduced soluble magnesium (Mg) and sodium (Na) contents, electrical conductivity (EC), and sodium adsorption ratio (SAR), and increased soil organic carbon (SOC) at a soil depth of 0–20 cm. VP application increased soil available phosphorus (P) by 34.7% and soluble potassium (K) by 69.3% at a soil depth of 0–20 cm. VS application slightly increased the SOC, total nitrogen (N), available P, and soluble K compared to the control. Overall, these results indicate that combining mineral amendments significantly increases wheat yield and improves soil properties in a saline area. Thus, we recommend the use of mineral amendments in saline coastal areas. [ABSTRACT FROM AUTHOR]

Further improvements to the yield potential of Chinese milk vetch seed are essential for the planting demand of green manure. Flower and pod development directly determines the number of seeds and the seed yield of Chinese milk vetch. However, the accumulation and translocation of dry matter and nitrogen between plant organs directly affects flower and pod development and morphological formation. There are few studies that analyse the relationship between the accumulation and transport of dry matter and nitrogen and the number of flowers, pods, grains and seed yield during Chinese milk vetch's critical development period. This study aimed to determine the seed yield response to dry matter and nitrogen accumulation and translocation during the Chinese milk vetch growth period and to quantify the relationship between these factors to predict Chinese milk vetch seed yield. Experiments were performed during the 2017–2018 and 2018–2019 growing seasons at the Dayuzhuang experimental field. The first experiment involved five foliar application stages (late wintering stage, returning green stage, squaring stage, pre-flowering stage, and 5 days after flowering) and six foliar application concentrations of borate solution (0, 500, 1000, 2000, 4000, and 6000 mg L-1). Experiment 2 included five foliar application stages (late wintering stage, returning green stage, squaring stage, pre-flowering stage, and 5 days after flowering) and six foliar application concentrations of paclobutrazol (0, 200, 300, 400, 500, and 600 mg L-1). When the dry matter mass in the full flowering stage was 3500–4500 kg hm-2, the seed yield reached more than 800 kg hm-2. When the translocated assimilates were stored in the vegetative organs before flowering, the assimilate translocation rate and their contributions to seed yield were 1500–1800 kg hm-2, 30–35%, and 28–38%, respectively, and the Chinese milk vetch seed yield was predicted to reach 800–1000 kg hm-2 at maturity. When the nitrogen translocation amount in the vegetative organs before flowering, the nitrogen translocation rate, and the contribution rate to the seed yield were 68–78 kg hm-2, 65–75%, and 75–85%, respectively, the Chinese milk vetch seed yield was predicted to reach 800–1000 kg hm-2 at maturity. If the accumulation and translocation index values of dry matter and nitrogen were lower or higher than the above ranges, the seed yield was lower than 800 kg hm-2. The results of this study revealed the mechanism by which dry matter and nitrogen accumulation and translocation affect the Chinese milk vetch seed yield. These findings enrich the seed yield formation theory of Chinese milk vetch. They provide an early determination and quantitative regulation of high and stable seed yield for Chinese milk vetch in the field and aid researchers to integrate multiple production technologies for the sustainable production of Chinese milk vetch. [ABSTRACT FROM AUTHOR]

Anaerobic digestion is a promising technology for recovering methane from organic wastewater and contributing to carbon neutrality in wastewater plants or industrial parks. However, the interference of pharmaceuticals and personal care products with anaerobic digestion is commonly overlooked. Carbamazepine, a typical antiepileptic drug, is frequently detected in sewage sludge, but its influence on anaerobic digestion has not been systematically reported. In this work, the effect of carbamazepine on the anaerobic digestion of lactic acid synthesis wastewater was revealed comprehensively. The results showed that carbamazepine could seriously disturb anaerobic digestion performance, the methane yield decreased from 275.12 to 182.04 mL/g lactic acid as the carbamazepine dosage rose from 0 to 0.14 mM. To better understand how the drug affected anaerobic digestion, model tests were conducted on four stages of hydrolysis, acidification, acetogenesis and methanogenesis. The model tests indicated that such drug could promote the solubilization of inoculum, thereby releasing polysaccharides and proteins. But the hydrolysis stage, commonly recognized as the rate-limiting step was restricted. Meanwhile, the enhanced acidification contributed to the accumulation of volatile fatty acids. Both acetogenesis and methanogenesis were severely disturbed eventually causing a significant decrease in methane yield. The level of interference of carbamazepine on anaerobic digestion was concluded as follows: acetogenesis > methanogenesis > hydrolysis > acidification > solubilization. The high-throughput sequencing revealed the abundance of Chloroflexi increased from 21.5% to 26.7% as a main responsibility for the volatile acid accumulation. The acetoclastic methanogen Methanosaeta decreased from 59.86% to 44.78%, while the hydrogenotrophic methanogens Methanobacterium and Methanomassiliicoccus increased from 28%, 0.5%–37.9% and 4.1%, respectively. Although the recovery of methane was limited for clean production, it was more recommendable to recover the volatile fatty acids from organic wastewater or sludge with high dosage of carbamazepine. [Display omitted] • Carbamazepine (CBZ) blocked CH 4 recovery from lactic acid anaerobic digestion. • CBZ inhibited all processes but acidification and inoculum solubilization. • The increased relative abundance of Chloroflexi contributed to over-acidification. • The shift in the type of methanogens was responsible for the decrease in CH 4. • More recommended to recover volatile acids from CBZ-containing wastewater. [ABSTRACT FROM AUTHOR]

Phosphorous (P) fixation in saline soils is a concern worldwide. To investigate optimization strategies for P fertilizer application that improve P use efficiency (PUE) and crop yield in saline soil, in terms of P sources and rates, we conducted a two year field experiment in the coastal saline area of China to investigate the effects of P rates and sources, including superphosphate (SSP), monoammonium phosphate (MAP) and ammonium polyphosphate (APP) on yield, aboveground P uptake, agronomy efficiency (AEP), and soil available P of winter wheat (Triticum aestivum L.). Wheat yield, under the three P sources, increased with P rates and reached a plateau under 20 kg P ha−1 SSP,18 kg P ha−1 MAP, and 17 kg P ha−1 MAP, respectively. The application of SSP increased the wheat yield by 9–11% compared to MAP and APP. The aboveground P uptake of winter wheat under SSP was 14% and 13% higher than MAP and APP, respectively, under the optimal P application rate. The AEP under SSP was higher than the other two P sources under the same P rate. SSP increased the soil Ca2+ concentration by 20–42%, but decreased the Na+ concentration by 14–18% at the P rate of 26 kg P ha−1 in all soil layers, including 0–20, 20–40, 40–60 cm, compared to CK (0 kg P ha−1). The soil Olsen-P concentration under APP was higher than the other P sources. This study suggests that optimizing P sources and rates can improve wheat yield, PUE, and soil quality in the coastal saline soil. [ABSTRACT FROM AUTHOR]

[Display omitted] • CaFe 2 O 4 NPs were produced to enhance butyrate-DF pathway for more H 2. • H 2 evolution via dark fermentation (DF) raised by 32.30% with CaFe 2 O 4 NPs. • Fe and Ca ions were released from CaFe 2 O 4 NPs to stimulate microbial activity. • Firmicutes in DF was selectively enriched in the presence of CaFe 2 O 4 NPs. • CaFe 2 O 4 NPs could promoted the expression of functional genes from DF. Dark fermentation (DF) is a green hydrogen (H 2) production process, but it is far below the theoretical H 2 yield. In this study, calcium ferrite nanoparticles (CaFe 2 O 4 NPs) were produced to augment H 2 yield via DF. The highest H 2 yield of 250.1 ± 6.5 mL/g glucose was achieved at 100 mg/L CaFe 2 O 4 NPs. Further increase in CaFe 2 O 4 NPs above 100 mg/L, such as 600 mg/L, would slightly lower H 2 yield to 208.6 ± 2.6 mL/g glucose. The CaFe 2 O 4 NPs in DF system released calcium and iron ions, promoting granular sludge formation and DF microbial activity. Soluble metabolites revealed that butyric acid was raised by CaFe 2 O 4 NPs, which indicated the improved metabolic pathway for more H 2. Microbial structure composition further illustrated that CaFe 2 O 4 NPs could increase the abundance of dominant microbial populations, with the supremacy of Firmicutes up to 71.22 % in the bioH 2 evolution group augmented with 100 mg/L CaFe 2 O 4 NPs. [ABSTRACT FROM AUTHOR]

In this paper, for the safety–critical systems with unmatched disturbances, a safe optimal robust control method based on neural network is proposed to ensure that the safety–critical system operates within its safe region and learns the optimal control strategy. The cost function which is the goal of the designers is augmented by a control barrier function (CBF) to achieve both safety and optimality. This method does not directly regard security as a constraint on the system state, but influences the cost function through a security penalty mechanism. An additional function is used to approximate the effect of the unmatched disturbances on the safety–critical systems. On the premise of satisfying the security and robustness, the neural network approximation method is used to learn the optimal control strategy. Based on Lyapunov stability theory, it is shown that the neural network-based safe optimal robust controller can guarantee all the signals of the resulting closed-loop systems to be uniformly ultimately bounded. Finally, two simulation examples are given to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

In this paper, a new adaptive critic design is proposed to approximate the online Nash equilibrium solution for the robust trajectory tracking control of non-zero-sum (NZS) games for continuous-time uncertain nonlinear systems. First, the augmented system was constructed by combining the tracking error and the reference trajectory. By modifying the cost function, the robust tracking control problem was transformed into an optimal tracking control problem. Based on adaptive dynamic programming (ADP), a single critic neural network (NN) was applied for each player to solve the coupled Hamilton–Jacobi–Bellman (HJB) equations approximately, and the obtained control laws were regarded as the feedback Nash equilibrium. Two additional terms were introduced in the weight update law of each critic NN, which strengthened the weight update process and eliminated the strict requirements for the initial stability control policy. More importantly, in theory, through the Lyapunov theory, the stability of the closed-loop system was guaranteed, and the robust tracking performance was analyzed. Finally, the effectiveness of the proposed scheme was verified by two examples. [ABSTRACT FROM AUTHOR]

Utilizing parallel learning technology and an event-triggering mechanism, we introduce an adaptive security tracking control approach for nonlinear systems with both matched and mismatched uncertainties. The methodology commences with an overview of the constraints imposed by the control barrier function (CBF) on the system state, followed by the selection of a suitable CBF. An augmented system is constructed by amalgamating the system state and tracking error, with the mismatched uncertainty being decomposed to introduce an auxiliary system. Incorporating the CBF into the performance metrics ensures that the system state remains within a secure region. Subsequently, the paper employs an event-triggering mechanism to derive an event-based secure Hamiltonian–Jacobi–Bellman (HJB) equation. An adaptive single-critic network, designed using parallel learning technology, approximates the solution to the event-based secure HJB equation. Lastly, the Lyapunov method is employed to demonstrate the uniform ultimate boundedness (UUB) of both the tracking error and weight error. The efficacy of the proposed method is validated through two nonlinear examples. [ABSTRACT FROM AUTHOR]

The accelerated chemical-industry has caused a rapid increase of calcium-containing alkali wastes, containing a large amount of calcium, magnesium, aluminum, and iron ions and caused a great risk to environment. Anaerobic digestion or dark fermentation is one of the most promising technologies to recover biogas, such as methane and hydrogen. Nevertheless, the hydrolysis processes of lignocellulosic biomass and waste activated sludge were the rate-limiting step of the biochemical reactions, which focused on pretreatment to improve the biodegradability of substrate. In addition, when some easily acidified wastes, such as kitchen residue, fruit and vegetable waste, and high concentration organic wastewater, are used as substrate to produce hydrogen and methane, volatile fatty acid accumulation often occurs, causing the process instability. Thus, this paper reviewed the main roles of calcium-based alkali materials such as calcium oxide, calcium peroxide and calcium hydroxide on the substrate pretreatment for obtaining high biodegradability, while others (e.g. calcium carbonate, lime and red muds) used as additives for maintaining process stability, thereby increasing biogas yield from anaerobic digestion and dark fermentation. [Display omitted] • Ca-alkali materials are used as pretreatment agents or additives for AD and DF. • Ca affects H 2 and CH 4 metabolisms as well as their syntrophic partners. • Alkalinity, mineral nutrient and microbial carrier are crucial factors. • Lime mud provides trace elements and improves process buffering effect. • Red mud promotes direct interspecies electron transfer. [ABSTRACT FROM AUTHOR]

We investigated the expression and functions of circular RNA (circRNA) circNINL and miR-921 in breast cancer (BC) in this study. We found that the expression of circNINL increased while the expression of miR-921 decreased in BC tissues and cell lines, and their anomalous expressions were associated with malignant features and poor prognostic of BC. Then, we demonstrated that circNINL could interact with miR-921 and facilitate BC cells malignant process including proliferation acceleration, migration enhancement and apoptosis evasion via sponging miR-921 in vitro. Further investigations revealed that circNINL/miR-921 axis could mediate the expression of ADAM9 which was a direct target of miR-921. In addition, we exhibited that ADAM9 may activate β-catenin signaling by interacting with E-cadherin. We presented the vital roles of circNINL/miR-921/ADAM9/β-catenin signaling in the progression of BC. [ABSTRACT FROM AUTHOR]

[Display omitted] • MgFe 2 O 4 and Ca 0.5 Mg 0.5 Fe 2 O 4 NPs were synthesized to improve bioH 2 yield. • MgFe 2 O 4 and Ca 0.5 Mg 0.5 Fe 2 O 4 NPs lowered the negative effects of humic acids. • MgFe 2 O 4 NPs enriched Clostridium_sensu_stricto_1 more than Ca 0.5 Mg 0.5 Fe 2 O 4 NPs. • MgFe 2 O 4 NPs improved bioH 2 yield higher than Ca 0.5 Mg 0.5 Fe 2 O 4 NPs. Dark fermentation (DF) is an eco-friendly process that simultaneously achieves organic matter degradation and obtains hydrogen (H 2). Nonetheless, low H 2 yield mainly caused by poor activity of key microbes, is still a problem that requires being resolved. In this work, MgFe 2 O 4 and Ca 0.5 Mg 0.5 Fe 2 O 4 nanoparticles (NPs) were synthetized and served as additives to boost H 2 form from DF. H 2 productivity gradually increased with the rise of NPs, and declined when NPs exceeded their optimal dosages. The highest H 2 yield was 183.6 ± 3.2 mL/g glucose at 100 mg/L of MgFe 2 O 4 NPs, being 35.2 % higher than that of the control yield (135.8 ± 3.1 mL/g glucose). However, the highest H 2 yield of 171.9 ± 2.5 mL/g glucose occurred at 400 mg/L of Ca 0.5 Mg 0.5 Fe 2 O 4 NPs, increasing by 26.6 % over the control. Interestingly, the two NPs favored the butyric acid pathway for H 2 synthesis. This provides guidance for multi-element oxide NPs used in DF. [ABSTRACT FROM AUTHOR]

Several reports have shown that pharmaceuticals and personal care products (PPCPs) have some negative effects on anaerobic digestion (AD), yet there are no convenient and efficient strategies for mitigating the adverse influences. The typical PPCPs of carbamazepine have a strong negative effect on lactic acid AD process. Therefore, in this work, novel lanthanum-iron oxide (LaFeO 3) nanoparticles (NPs) were used for adsorption and bioaugmentation to weak the negative effects of carbamazepine. The adsorption removal of carbamazepine increased from 0 to 44.30% as the dosage of LaFeO 3 NPs was increased from 0 to 200 mg/L, providing the necessary prerequisites for bioaugmentation. Adsorption reduced the probability of direct contact between carbamazepine and anaerobes, partly alleviating the inhibition of carbamazepine on microbes. The highest methane (CH 4) yield induced by LaFeO 3 NPs (25 mg/L) was 226.09 mL/g lactic acid, increasing by 30.06% compared to the control yield with a recovery to 89.09% of the normal CH 4 yield. Despite the ability of LaFeO 3 NPs to restore normal AD performance, the biodegradation rate of carbamazepine remained below 10% due to its anti-biodegradability. Bioaugmentation was primarily reflected in the enhanced bioavailability of dissolved organic matter, while the intracellular LaFeO 3 NPs promoted coenzyme F420 activity through binding to humic substances. Under the mediation of LaFeO 3 , a direct interspecies electron transfer system with Longilinea and Methanosaeta as functional bacteria was successfully constructed and the corresponding electron transfer rate was accelerated from 0.021 s−1 to 0.033 s−1. LaFeO 3 NPs eventually recovered AD performance under carbamazepine stress in an adsorption and bioaugmentation manner. [Display omitted] • Nano LaFeO 3 remediated AD performance via adsorption and bioaugmentation. • Sorption dominated while biological action subordinated in carbamazepine removal. • CH 4 yield increased by 30.06% in the group of 25 mg/L nano-LaFeO 3. • Nano LaFeO 3 could regulate anaerobes toward efficient CH 4 production. • Longilinea and Methanosaeta were the bacteria responsible for electron transfer. [ABSTRACT FROM AUTHOR]

[Display omitted] • BioH 2 yield via dark fermentation increased by 47% with LaFeO 3 NPs. • Butyrate fermentation pathway was strengthened using LaFeO 3 NPs. • Gene copy number of hydrogenase was elevated adding LaFeO 3 NPs. • Firmicutes was selectively enriched and colonized by LaFeO 3 supplementation. • Glycolysis was promoted with LaFeO 3 addition by PICRUSt2 analysis. Low hydrogen (H 2) yield via dark fermentation often occurs, being mainly due to H 2 generation pathway shift. In this study, lanthanum-iron oxide nanoparticles (LaFeO 3 NPs) were prepared to investigate their effects on bioH 2 production. The highest H 2 yield of 289.8 mL/g glucose was found at 100 mg/L of LaFeO 3 , being 47.6% higher than that from the control (196.3 mL/g glucose). The relative abundance of Firmicutes increased from 54.2% to 67.5%. The large specific surface area of LaFeO 3 provided sufficient sites for the colonization of Firmicutes and increased the bacterial access to nutrients. Additionally, the La3+ gradually released from LaFeO 3 NPs raised microbial transmembrane transport capacity, promoting glycolytic efficiency and Fe availability, thereby increasing hydrogenase content, and shifting the bioH 2 evolution to butyrate pathway for more H 2. This provides the novelty for biochemical utilization of La and new insights into the improved H 2 yield amended with LaFeO 3. [ABSTRACT FROM AUTHOR]

[Display omitted] • CoFe 2 O 4 , CoAl 0.2 Fe 1.8 O 4 and CoCu 0.2 Fe 1.8 O 4 NPs promoted DIET. • CoAl 0.2 Fe 1.8 O 4 and CoCu 0.2 Fe 1.8 O 4 NPs enriched methanogens Methanobacterium. • CoAl 0.2 Fe 1.8 O 4 NPs addition enhanced H 2 /CO 2 methanogenesis pathway. • New strategy of NP structure and composition design improved bioCH 4 production. • Excess NPs (above 300 mg/L) revealed negative effects on anaerobic digestion. Some inhibition of biomethane (bioCH 4) production system can be observed, which is due to the propionic acid generation from lactic acid degradation. In this work, the three cobalt ferrate-based nanoparticles (NPs) such as CoFe 2 O 4 , CoAl 0.2 Fe 1.8 O 4 and CoCu 0.2 Fe 1.8 O 4 were synthesized to promote the bioCH 4 evolution from lactic acid. The CH 4 yields from the CoAl 0.2 Fe 1.8 O 4 , CoCu 0.2 Fe 1.8 O 4 and CoFe 2 O 4 groups at 300 mg/L of NPs were 431.52, 392.12 and 396.6 mL/g lactic acid, respectively. Moreover, the highest CH 4 yield was 34.15% higher than that of the control reactor (321.67 mL/g lactic acid) without NPs. The three NPs accelerated lactic acid biodegradation and propionic acid conversion, thus obtaining more CH 4. Surprisingly, microbial structure revealed that CoAl 0.2 Fe 1.8 O 4 increased the abundance of Bacteroidetes_vadinHA17 to 16.6%, promoting the conversion from propionic acid to acetic acid. Meanwhile, the abundance of Methanobacterium in archaeal community from CoAl 0.2 Fe 1.8 O 4 group rose from 45.81% to 68.45%, which facilitated bioCH 4 production. [ABSTRACT FROM AUTHOR]

Abstract: Sixteen empirical global radiation models based on meteorological variables were generated and validated using monthly or monthly mean daily data in 1968–1998 at 45 stations in China when sunshine hours were unavailable. Most of these equations can give good results, and at some stations, some equations can give better results than those of the Angström model. The Angström model and its three revised equations based on meteorological variables were also validated. These revised models can give better results than those of the original Angström model. [Copyright &y& Elsevier]

The microstructural and microhardness evolution, as well as the deformation/phase transformation mechanism in a hot isostatic pressed Ti-6Al-4V alloy during multi-pass deformation at variable temperature parameters of 950-900-850 °C and 950-850-900 °C were investigated. The result shows that dynamic recrystallization of β phase for one-pass deformation, been/kinking, fragmentation and spheroidization of lamellar α phase for two-pass and three-pass deformation occurred during multi-pass deformation. And the evolution process of lamellar α phase included two aspects: rotation and the change in length, thick, spheroidization. The orientation distribution of lamellar α changes from bimodal to single peak, and the angle of single peak is close to 95°with the compression axis. And the spheroidization of lamellar α phase contains the formation of sub-structure, localized shear deformation and fracture of su-bstructure, diffuseness of β phase, separation and spheroidization. The spheroidization fraction of lamellar α phase gradually increases with the increase of strain rates. For different temperature matching (950-900-850 °C and 950-850-900 °C), the significant influence is the variation trend and degree in the length and thickness of lamellar α phase. For the analysis of mechanical properties, it is found that the microhardness value increase with the increase of strain and the main influence of integrated hardness during multi-pass deformation is the lamellar structure and the contribution value of c ɑl is greater at higher deformation temperature. • The multi-pass hot compression features of Ti-6Al-4V alloy prepared by hot isostatic pressing(HIP) were study. • The microstructure evolution of α phase at variable temperature parameters corresponding to complex strain matching was invested. • The influence of integrated hardness and contribution value was revealed. [ABSTRACT FROM AUTHOR]

Acetate and H 2 are the two main substrates for CH 4 production, while the CH 4 generation from H 2 can be regarded as the process of transferring electrons from volatile fatty acids or alcohols to CO 2 and H 2 acts as an electron carrier. This process is called interspecies H 2 transfer (IHT). In addition to IHT there is a direct interspecies electron transfer (DIET) pathway between syntrophs and methanogens in syntrophic metabolism, which can directly transfer electrons to reduce CO 2 to CH 4 with lower electron losses. In this work, the DIET process is strengthened by adding graphite felt as an electron carrier. • Electrogenic bacteria such as Geobacter was enriched in the present of graphite felt. • The enrichment of electrogenic bacteria facilities the DIET for methane production. • Propionate and butyrate were successfully degraded under high H 2 partial pressure. • Methane production were significantly increased by the enrichment of DIET pathway. Direct interspecies electron transfer (DIET) was considered to replace interspecies H 2 transfer to enhance syntrophic metabolism during the anaerobic digestion. The graphite felt with excellent electrical conductivity was added into a semi-continuous reactor as a conductive material, strengthening DIET in enhancing the degradation of propionate and butyrate. The final average CH 4 production rate increased by 19.1% and 16.7%, respectively, during the propionate and butyrate degradation. Microbial community analysis revealed that the relative abundance of the microflora that could participate in DIET, like Geobacter , Methanosaeta and Methanosarcina species, was greatly improved in the presence of graphite felt. Further experiments showed that the high H 2 partial pressure had no obvious effect on the degradation of propionate and butyrate in the graphite felt-supplement reactors. [ABSTRACT FROM AUTHOR]