Mixed‑Dimensional Assembly Strategy to Construct Reduced Graphene Oxide/Carbon Foams Heterostructures for Microwave Absorption,Anti‑Corrosion and Thermal Insulation

Considering the serious electromagnetic wave(EMW)pollution problems and complex application condition,there is a pressing need to amalgamate multiple functionalities within a single substance.However,the effective integration of diverse functions into designed EMW absorption materials still faces the huge challenges.Herein,reduced graphene oxide/carbon foams(RGO/CFs)with two-dimensional/three-dimensional(2D/3D)van der Waals(vdWs)heterostructures were meticulously engineered and synthesized utilizing an efficient methodology involving freeze-drying,immersing absorption,secondary freeze-drying,followed by carbonization treatment.Thanks to their excellent linkage effect of amplified dielectric loss and optimized impedance matching,the designed 2D/3D RGO/CFs vdWs heterostructures demonstrated commendable EMW absorption performances,achieving a broad absorption bandwidth of 6.2 GHz and a reflection loss of-50.58 dB with the low matching thicknesses.Furthermore,the obtained 2D/3D RGO/CFs vdWs heterostructures also displayed the significant radar stealth properties,good corrosion resistance performances as well as outstanding thermal insulation capabilities,displaying the great potential in complex and variable environments.Accordingly,this work not only demonstrated a straightforward method for fabricating 2D/3D vdWs heterostructures,but also outlined a powerful mixeddimensional assembly strategy for engineering multifunctional foams for electromagnetic protection,aerospace and other complex conditions.

Laser‑Induced and MOF‑Derived Metal Oxide/Carbon Composite for Synergistically Improved Ethanol Sensing at Room temperature

Advancements in sensor technology have significantly enhanced atmospheric monitoring.Notably,metal oxide and carbon(MO_(x)/C)hybrids have gained attention for their exceptional sensitivity and room-temperature sensing performance.However,previous methods of synthesizing MO_(x)/C composites suffer from problems,including inhomogeneity,aggregation,and challenges in micropatterning.Herein,we introduce a refined method that employs a metal–organic framework(MOF)as a precursor combined with direct laser writing.The inherent structure of MOFs ensures a uniform distribution of metal ions and organic linkers,yielding homogeneous MO_(x)/C structures.The laser processing facilitates precise micropatterning(<2μm,comparable to typical photolithography)of the MO_(x)/C crystals.The optimized MOF-derived MO_(x)/C sensor rapidly detected ethanol gas even at room temperature(105 and 18 s for response and recovery,respectively),with a broad range of sensing performance from 170 to 3,400 ppm and a high response value of up to 3,500%.Additionally,this sensor exhibited enhanced stability and thermal resilience compared to previous MOF-based counterparts.This research opens up promising avenues for practical applications in MOF-derived sensing devices.

MIL-100(V) derived porous vanadium oxide/carbon microspheres with oxygen defects and intercalated water molecules as high-performance cathode for aqueous zinc ion battery

The development of aqueous zinc ion battery cathode materials with high capacity and high magnification is still a challenge.Herein,porous vanadium oxide/carbon(p-VO_(x)@C,mainly VO_(2) with a small amount of V_(2)O_(3)) core/shell microspheres with oxygen vacancies are facilely fabricated by using a vanadium-based metal-organic framework(MIL-100(V)) as a sacrificial template.This unique structure can improve the conductivity of the VO_(x),accelerate electrolyte diffusion,and suppress structural collapse during circulation.Subsequently,H_(2)O molecules are introduced into the interlayer of VO_(x) through a highly efficient in-situ electrochemical activation process,facilitating the intercalation and diffusion of zinc ions.After the activation,an optimal sample exhibits a high specific capacity of 464.3 mA h g^(-1) at0.2 A g^(-1) and 395.2 mA h g^(-1) at 10 A g^(-1),indicating excellent rate performance.Moreover,the optimal sample maintains a capacity retention of about 89.3% after 2500 cycles at 10 A g^(-1).Density functional theory calculation demonstrates that the presence of oxygen vacancies and intercalated water molecules can significantly reduce the diffusion barrier for zinc ions.In addition,it is proved that the storage of zinc ions in the cathode is achieved by reversible intercalation/extraction during the charge and discharge process through various ex-situ analysis technologies.This work demonstrates that the p-VO_(x)@C has great potential for applications in aqueous ZIBs after electrochemical activation.

Mechanically flexible reduced graphene oxide/carbon composite films for high-performance quasi-solid-state lithium-ion capacitors

Practical applications of diverse flexible wearable electronics require electrochemical energy storage(EES)devices with multiple configurations.Moreover,to fabricate flexible EES devices with high energy density and stability,organic integration from electrode design to device assembly is required.To address these challenges,a free-standing reduced graphene oxide(rGO)/carbon film with a unique sandwich structure has been designed via the assistance of vacuum-assistant filtration for lithium-ion capacitors(LICs).The graphene acts as not only a binder to construct a three-dimensional conductive network but also an active material to provide additional capacitive lithium storage sites,thus enabling fast ion/electron transport and improving the capacity.The designed rGO/hard carbon(rGO/HC)and rGO/activated carbon(rGO/AC)free-standing films exhibit enhanced specific capacities(513.7 mA h g^(-1)for rGO/HC and 102.8 mA h g^(-1)for rGO/AC)and excellent stability.Moreover,the integrated flexible quasi-solid-state rGO/AC//rGO/HC LIC devices possess a maximum energy density of 138.3 Wh kg^(-1),a high power density of 11 kW kg^(-1),and improved cycling performance(84.4%capacitance maintained after 10,000 cycles),superior to the AC//HC LIC(43.5%retention).Such a strategy enlightens the development of portable flexible LICs.

Poly(ionic liquid)-crosslinked graphene oxide/carbon nanotube membranes as efficient solar steam generators

Graphene oxide(GO)is regarded as a promising candidate to construct solar absorbers for addressing freshwater crisis,but the easy delamination of GO in water poses a critical challenge for practical solar desalination.Herein,we improve the stability of GO membranes by a self-crosslinking poly(ionic liquid)(PIL)in a mild condition,which crosslinks neighbouring GO nanosheets without blemishing the hydrophilic structure of GO.By further adding carbon nanotubes(CNTs),the sandwiched GO/CNT@PIL(GCP)membrane displays a good stability in pH=1 or 13 solution even for 270 days.The molecular dynamics simulation results indicate that the generation of water nanofluidics in nanochannels of GO nanosheets remarkably reduces the water evaporation enthalpy in GCP membrane,compared to bulk water.Consequently,the GCP membrane exhibits a high evaporation rate(1.87 kg m^(-2)h^(-1))and displays stable evaporation rates for 14 h under 1 kW m^(-2)irradiation.The GCP membrane additionally works very well when using different water sources(e.g.,dye-polluted water)or even strong acidic solution(pH=1)or basic solution(pH=13).More importantly,through bundling pluralities of GCP membrane,an efficient solar desalination device is developed to produce drinkable water from seawater.The average daily drinkable water amount in sunny day is 10.1 kg m^(-2),which meets with the daily drinkable water needs of five adults.The high evaporation rate,long-time durability and good scalability make the GCP membrane an outstanding candidate for practical solar seawater desalination.

Pseudo-capacitive Behavior of Cobalt Hydroxide/Carbon Nanotubes Composite Prepared by Cathodic Deposition

A novel type of composite electrode based on nmltiwalled carbon nanotubes coated with sheet-like cobalt hydroxide particles was used in supercapacitors. Cobalt hydroxide cathodlcally deposited fiom Co（NO3）O2 solution with carbon nanotubes as matrix exhibited large pseudo-capacitance of 322 F/g in 1 mol/L KOH. To characterize the cobalt hydroxide nanocomposite electrode, a charge-discharge cycling test, cyclic voltammetry, and an impedance test were done. This cobalt hydroxide composite exhibiting excellent pseudo-capacitive behavior （i.c. high reversibility, high specific capacitance, low impedance）, was demonstrated to be a candidate for the application of electrochemical supercapacitors. A combined capacitor consisting of cobalt hydroxide composite as a cathode and activated carbon fiber as an anode was reported. The electrochemical pcrformance of the combined capacitor was characterized by cyclic voltammetry and a dc charge/discharge test. The combined capacitor showed ideal capacitor behavior with an extended operating voltage of 1.4 V. According to the extended operating voltage, the energy density of the combined capacitor at a current density of 100 mA/cm^2 was found to be 11 Wh/kg. The combined capacitor exhibited high-energy density and stable power characteristics,

Nickel Oxide/Carbon Nanotubes Nanocomposite for Electrochemical Capacitance

A nanocomposite of nickel oxide/carbon nanotubes was prepared through a simple chemical precipitation followed by thermal annealing. The electrochemical capacitance of this electrode material was studied. When the mass fraction of CNTs (carbon nanotubes) in NiO/CNT composites increases, the electrical resistivity of nanocomposites decreases and becomes similar to that of pure CNTs when it reaches 30%. The specific surface area of composites increases with increasing CNT mass fraction and the specific capacitance reaches 160 F/g under 10 mA/g discharge current density at CNT mass fraction of 10%.

Effects of Catalyst and Additive Containing Li, Na, or Ca on Reduction of Iron Oxide/Carbon Composite Pellets

The catalyst containing 0.69% (mass fraction) of Li+, Na+, or Ca2+ were synthesized, and the catalytic effect on the reduction of iron oxide/carbon composite pellets were investigated by comparing with that of additive at 850 degreesC. The effect of the catalyst was greater than that of the additive, it can be considered that catalyst promoted the formation of iron nucleus early on reduction processes of iron oxide/carbon composite pellets. In addition, both effects of catalyst and additive increased after added carbon powder into the pellets, but the extent of increase decreased when the carbon powder exceeded a suitable content (about 4%), this amount is less than that of carbon needed theoretically on the reduction from hematite to iron.

Pseudo-capacitance of ruthenium oxide/carbon black composites for electrochemical capacitors

Hydrous ruthenium oxide was formed by a new process. The precursor was obtained by mixing the aqueous solutions of RuCl3xH2O and NaHCO3. The addition of NaHCO3 led to the formation of an oxide with extremely fine RuO2 particles forming a porous network structure in the oxide electrode. Polyethylene glycol was added as a controller to partly inhibit the sol-gel reaction. The rate capacitance of 530 F·g^-1 was measured for the powder formed at an optimal annealing temperature of 210℃. Several details concerning this new material, including crystal structure, particle size as a function of temperature, and electrochemical properties, were also reported. In addition, the rate capacitance of the composite electrode reached 800 F·g^-1 after carbon black was added. By using the modified electrode of a RuO2/carbon black composite electrode, the electrochemical capacitor exhibits high energy density and stable power characteristics. The values of specific energy and maximum specific power of 24 Wh·kg^-1 and 4 kW·kg^-1, respectively, are demonstrated for a cell voltage between 0 and 1 V.

Coral-Like Yolk–Shell-Structured Nickel Oxide/Carbon Composite Microspheres for High-Performance Li-Ion Storage Anodes

In this study, coral?like yolk–shell?structured NiO/C composite microspheres(denoted as CYS?NiO/C) were prepared using spray pyrolysis. The unique yolk–shell structure was characterized, and the formation mechanism of the structure was proposed. Both the phase separation of the polyvinylpyrrolidone and polystyrene(PS) colloidal solution and the decompo?sition of the size?controlled PS nanobeads in the droplet played crucial roles in the formation of the unique coral?like yolk–shell structure. The CYS?NiO/C microspheres delivered a reversible discharge capacity of 991 mAh g^(-1) after 500 cycles at the current density of 1.0 A g^(-1). The dis?charge capacity of the CYS?NiO/C microspheres after the 1000 th cycle at the current density of 2.0 A g^(-1) was 635 mAh g^(-1), and the capacity retention measured from the second cycle was 91%. The final discharge capacities of the CYS?NiO/C microspheres at the current densities of 0.5, 1.5, 3.0, 5.0, 7.0, and 10.0 A g^(-1) were 753, 648, 560, 490, 440, and 389 mAh g^(-1), respectively. The synergetic e ect of the coral?like yolk–shell structure with well?defined interconnected mesopores and highly conductive carbon resulted in the excellent Li+?ion storage properties of the CYS?NiO/C microspheres.

Performance of a combined capacitor based on ultrafine nickel oxide/carbon nanotubes composite electrodes

A new sol-gel process for the preparation of ultrafine nickel hydroxideelectrode materials was developed. The composite electrodes consisting of carbon nanotubes andNi(OH)_2 were developed by mixing the hydroxide and carbon nanotubes together in different massratios. In order to enhance energy density, a combined type pseudocapacitor/electric double layercapacitor was considered and its electrochemical properties were characterized by cyclic voltammetryand dc charge/discharge test. The combined capacitor shows excellent capacitor behavior with anoperating voltage up to 1.6 V in KOH aqueous electrolyte. Stable charge/discharge behaviors wereobserved with much higher specific capacitance values of 24 F/g compared with that of EDLC (12 F/g)by introducing 60 percent Ni(0H)_2 in the anode material. By using the modified anode of aNi(OH)_2/carbon nanotubes composite electrode, the specific capacitance of the cell was lesssensitive to discharge current density compared with that of the capacitor employing pure nickelhydroxide as anode. The combined capacitor in this study exhibits high energy density and stablepower characteristics.

Experimental investigation for machinability aspects of graphene oxide/carbon fiber reinforced polymer nanocomposites and predictive modeling using hybrid approach

This article explores the drilling behavior of polymer nanocomposites reinforced by Graphene oxide/Carbon fiber using a hybrid method of Grey theory and Principal component analysis(GR-PCA).An online digital dynamometer was employed for the evaluation of Thrust Force and Torque.The image processing technique computes the delamination.Response surface methodology(RSM)considers the parameters,namely,drilling speed(S),feed rate(F),Graphene Oxide wt.%(G)in designing the experimentation array.Principal component analysis(PCA)was used to tackle the response priority weight during the combination of multiple functions.Analysis of variance(ANOVA)scrutinized the influence of parameters and intended the regression models to predict the response.GR-PCA evaluated the optimal parametric setting and remarked that feed rate acts as the most predominant factor.The higher feed rate and wt.%of G is responsible for surface damages like fiber pull-out,fiber fracture and cracks.A significant improvement in drilling responses has been obtained and also validates through confirmatory test and microstructure investigations.

Cotton pads-derived carbon materials/reduced graphene oxide modified with polypyrrole for electrode of supercapacitors

This study investigates the influence of electropolymerization conditions on the deposition of polypyrrole(PPy)onto cotton-derived carbon fiber(CF)modified with reduced graphene oxide(rGO)for supercapacitors applications using an experimental/theorical approach.The surface modification of CF by rGO and/or by PPy electrodeposited at 10,25 and 50 mV s^(-1) was thoroughly examined physicochemical and electrochemically.Composite electrodes comprising CF-rGo-PPy,synthesized via electropolymerization at 25 mV s^(-1),demonstrated a remarkable increase in capacitance,showcasing~742 F g^(-1) compared to 153 F g^(-1) for CF.SEM,N_(2)-surface area,XPS,and TD-DFT approach revealed that the higher capacitance observed in CF-rGo-PPy electrodes underscores the influence of morphology and charged nitrogen species on the electrochemical performance of these modified electrodes.Notably,this electrode material achieves a specific capacitance retention of~96%of their initial capacitance after 10000 cycles at 0.5 A g^(-1) measured in a two-electrodes cell configuration.This work also discusses the influence of the scan rate used for pyrrole electropolymerization on the pseudocapacitance contribution of PPy and its possible effect on the porosity of the material.These results highlight the importance of appropriate electropolymerization conditions that allow obtaining the synergistic effect between CF,rGO and PPy.

Chemico-biological conversion of carbon dioxide

The unabated carbon dioxide(CO_(2))emission into the atmosphere has exacerbated global climate change,resulting in extreme weather events,biodiversity loss,and an intensified greenhouse effect.To address these challenges and work toward carbon(C)neutrality and reduced CO_(2)emissions,the capture and utilization of CO_(2)have become imperative in both scientific research and industry.One cutting-edge approach to achieving efficient catalytic performance involves integrating green bioconversion and chemical conversion.This innovative strategy offers several advantages,including environmental friendliness,high efficiency,and multi-selectivity.This study provides a comprehensive review of existing technical routes for carbon sequestration(CS)and introduces two novel CS pathways:the electrochemicalbiological hybrid and artificial photosynthesis systems.It also thoroughly examines the synthesis of valuable Cnproducts from the two CS systems employing different catalysts and biocatalysts.As both systems heavily rely on electron transfer,direct and mediated electron transfer has been discussed and summarized in detail.Additionally,this study explores the conditions suitable for different catalysts and assesses the strengths and weaknesses of biocatalysts.We also explored the biocompatibility of the electrode materials and developed novel materials.These materials were specifically engineered to combine with enzymes or microbial cells to solve the biocompatibility problem,while improving the electron transfer efficiency of both.Furthermore,this review summarizes the relevant systems developed in recent years for manufacturing different products,along with their respective production efficiencies,providing a solid database for development in this direction.The novel chemical-biological combination proposed herein holds great promise for the future conversion of CO_(2)into advanced organic compounds.Additionally,it offers exciting prospects for utilizing CO_(2)in synthesizing a wide range of industrial products.Ultimately,the present study provides a unique perspective for achieving the vital goals of“peak shaving”and C-neutrality,contributing significantly to our collective efforts to combat climate change and its associated challenges.

Highly dispersed MgInCe-mixed metal oxides catalyzed direct carbonylation of glycerol and CO_(2)into glycerol carbonate

Glycerol carbonate,an important glycerol value-added product,has been widely used as an active intermediate and inert solvent in the synthesis of cosmetics,detergents,chemical intermediates,polymers,and so on.The direct carbonylation from glycerol with CO_(2)is considered a promising route,but still tough work due to the thermodynamic stability and the kinetic inertness of CO_(2).In this work,highlyselective direct carbonylation of glycerol and CO_(2)into glycerol carbonate has been achieved over highly dispersed MgInCe-mixed metal oxides(MgInCe-MMO),which were prepared through the topological transformation derived from the MgInCe-layered double hydroxides(MgInCe-LDHs).By precisely modulating the surface basic-acidic properties and the oxygen vacancies,an efficient carbonylation of glycerol with CO_(2)has been achieved with a selectivity of up to>99%to glycerol carbonate.Deep investigation into the synergistic catalysis of base-acid sites and oxygen vacancies has been clarified.

Effects of drip and flood irrigation on carbon dioxide exchange and crop growth in the maize ecosystem in the Hetao Irrigation District,China

Drip irrigation and flood irrigation are major irrigation methods for maize crops in the Hetao Irrigation District,Inner Mongolia Autonomous Region,China.This research delves into the effects of these irrigation methods on carbon dioxide(CO_(2))exchange and crop growth in this region.The experimental site was divided into drip and flood irrigation zones.The irrigation schedules of this study aligned with the local commonly used irrigation schedule.We employed a developed chamber system to measure the diurnal CO_(2)exchange of maize plants during various growth stages under both drip and flood irrigation methods.From May to September in 2020 and 2021,two sets of repeated experiments were conducted.In each experiment,a total of nine measurements of CO_(2)exchange were performed to obtain carbon exchange data at different growth stages of maize crop.During each CO_(2)exchange measurement event,CO_(2)flux data were collected every two hours over a day-long period to capture the diurnal variations in CO_(2)exchange.During each CO_(2)exchange measurement event,the biological parameters(aboveground biomass and crop growth rate)of maize and environmental parameters(including air humidity,air temperature,precipitation,soil water content,and photosynthetically active radiation)were measured.The results indicated a V-shaped trend in net ecosystem CO_(2)exchange in daytime,reducing slowly at night,while the net assimilation rate(net primary productivity)exhibited a contrasting trend.Notably,compared with flood irrigation,drip irrigation demonstrated significantly higher average daily soil CO_(2)emission and greater average daily CO_(2)absorption by maize plants.Consequently,within the maize ecosystem,drip irrigation appeared more conducive to absorbing atmospheric CO_(2).Furthermore,drip irrigation demonstrated a faster crop growth rate and increased aboveground biomass compared with flood irrigation.A strong linear relationship existed between leaf area index and light utilization efficiency,irrespective of the irrigation method.Notably,drip irrigation displayed superior light use efficiency compared with flood irrigation.The final yield results corroborated these findings,indicating that drip irrigation yielded higher harvest index and overall yield than flood irrigation.The results of this study provide a basis for the selection of optimal irrigation methods commonly used in the Hetao Irrigation District.This research also serves as a reference for future irrigation studies that consider measurements of both carbon emissions and yield simultaneously.

Carbon Monoxide Modulates Auxin Transport and Nitric Oxide Signaling in Plants under Iron Deficiency Stress

Carbon monoxide(CO)and nitric oxide(NO)are signal molecules that enhance plant adaptation to environmental stimuli.Auxin is an essential phytohormone for plant growth and development.CO and NO play crucial roles in modulating the plant’s response to iron deficiency.Iron deficiency leads to an increase in the activity of heme oxygenase(HO)and the subsequent generation of CO.Additionally,it alters the polar subcellular distribution of Pin-Formed 1(PIN1)proteins,resulting in enhanced auxin transport.This alteration,in turn,leads to an increase in NO accumulation.Furthermore,iron deficiency enhances the activity of ferric chelate reductase(FCR),as well as the expression of the Fer-like iron deficiency-induced transcription factor 1(FIT)and the ferric reduction oxidase 2(FRO2)genes in plant roots.Overexpression of the long hypocotyl 1(HY1)gene,which encodes heme oxygenase,or the CO donor treatment resulted in enhanced basipetal auxin transport,higher FCR activity,and the expression of FIT and FRO2 genes under Fe deficiency.Here,a potential mechanism is proposed:CO and NO interact with auxin to address iron deficiency stress.CO alters auxin transport,enhancing its accumulation in roots and up-regulating key iron-related genes like FRO2 and IRT1.Elevated auxin levels affect NO signaling,leading to greater sensitivity in root development.This interplay promotes FCR activity,which is crucial for iron absorption.Together,these molecules enhance iron uptake and root growth,revealing a novel aspect of plant physiology in adapting to environmental stress.

In-depth analysis of VARTM-based solid-state supercapacitors utilizing CNT-dispersed cobalt-bismuth-samarium ternary hydroxide on woven carbon fiber for enhanced energy storage

Multi-metal hydroxides possess unique physical and chemical properties,making them promising candidates for supercapacitor working electrodes.Enhancing their electrochemical performance can be achieved through a combination with carbon materials.In this study,we synthesized a composite material by hydrothermally dispersed 4,6,and 10 wt%carbon nanotubes(CNT)into ternary cobaltbismuth-samarium hydroxide(CoBiSm-TOH).These nanocomposites were employed as the material for the working electrode in a supercapacitor.The findings reveal that at 1.5 A/g,the specific capacitance of CNT3@CoBiSm-TOH,using a three-electrode system,was found to be 852.91 F/g,higher than that of CoBi-BOH,CoBiSm-TOH,CNT1@CoBiSm-TOH and CNT5@CoBiSm-TOH-measuring 699.69,750.34,789.54 and 817.79 F/g,respectively.Moreover,CNT3@CoBiSm-TOH electrodes exhibited a capacitance retention of around 88%over 10,000 cycles.To demonstrate practical applicability,CNT3@CoBiSm-TOH was grown on woven carbon fiber(WCF),and a solid-state supercapacitor device was developed using the VARTM(vacuum-assisted resin transfer molding).This device displayed a specific capacitance of 272.67 F/g at 2.25 A/g.Notably,it achieved a maximum energy density of 53.01 Wh/kg at a power density of 750 W/kg and sustained excellent cycle stability over 50,000 cycles,maintaining 70%of its initial capacitance.These results underscore the importance of interfacial nanoengineering and provide crucial insights for the development of future energy storage devices.

Carbon dioxide enrichment affected flower numbers transiently and increased successful post-pollination development stably but without altering final acorn production in mature pedunculate oak (Quercus robur L.)

Acorn production in oak(Quercus spp.)shows considerable inter-annual variation,known as masting,which provides a natural defence against seed predators but a highly-variable supply of acorns for uses such as in commercial tree planting each year.Anthropogenic emissions of greenhouse gases have been very widely reported to influence plant growth and seed or fruit size and quantity via the‘fertilisation effect’that leads to enhanced photosynthesis.To examine if acorn production in mature woodland communities will be affected by further increase in CO_(2),the contents of litter traps from a Free Air Carbon Enrichment(FACE)experiment in deciduous woodland in central England were analysed for numbers of flowers and acorns of pedunculate oak(Quercus robur L.)at different stages of development and their predation levels under ambient and elevated CO_(2) concentrations.Inter-annual variation in acorn numbers was considerable and cyclical between 2015 and 2021,with the greatest numbers of mature acorns in 2015,2017 and 2020 but almost none in 2018.The numbers of flowers,enlarged cups,immature acorns,empty acorn cups,and galls in the litter traps also varied amongst years;comparatively high numbers of enlarged cups were recorded in 2018,suggesting Q.robur at this site is a fruit maturation masting species(i.e.,the extent of abortion of pollinated flowers during acorn development affects mature acorn numbers greatly).Raising the atmospheric CO_(2) concentration by 150μL L^(−1),from early 2017,increased the numbers of immature acorns,and all acorn evidence(empty cups+immature acorns+mature acorns)detected in the litter traps compared to ambient controls by 2021,but did not consistently affect the numbers of flowers,enlarged cups,empty cups,or mature acorns.The number of flowers in the elevated CO_(2) plots’litter traps was greater in 2018 than 2017,one year after CO_(2) enrichment began,whereas numbers declined in ambient plots.Enrichment with CO_(2) also increased the number of oak knopper galls(Andricus quercuscalicis Burgsdorf).We conclude that elevated CO_(2) increased the occurrence of acorns developing from flowers,but the putative benefit to mature acorn numbers may have been hidden by excessive pre-and/or post-dispersal predation.There was no evidence that elevated CO_(2) altered masting behaviour.

Hybrid modeling for carbon monoxide gas-phase catalytic coupling to synthesize dimethyl oxalate process

Ethylene glycol(EG)plays a pivotal role as a primary raw material in the polyester industry,and the syngas-to-EG route has become a significant technical route in production.The carbon monoxide(CO)gas-phase catalytic coupling to synthesize dimethyl oxalate(DMO)is a crucial process in the syngas-to-EG route,whereby the composition of the reactor outlet exerts influence on the ultimate quality of the EG product and the energy consumption during the subsequent separation process.However,measuring product quality in real time or establishing accurate dynamic mechanism models is challenging.To effectively model the DMO synthesis process,this study proposes a hybrid modeling strategy that integrates process mechanisms and data-driven approaches.The CO gas-phase catalytic coupling mechanism model is developed based on intrinsic kinetics and material balance,while a long short-term memory(LSTM)neural network is employed to predict the macroscopic reaction rate by leveraging temporal relationships derived from archived measurements.The proposed model is trained semi-supervised to accommodate limited-label data scenarios,leveraging historical data.By integrating these predictions with the mechanism model,the hybrid modeling approach provides reliable and interpretable forecasts of mass fractions.Empirical investigations unequivocally validate the superiority of the proposed hybrid modeling approach over conventional data-driven models(DDMs)and other hybrid modeling techniques.