Colitis-associated colorectal cancer(CAC)is a major contributor to cancer-related mortality worldwide.Titanium dioxide(TiO_(2),E171),a widely used food additive,has been insufficiently studied regarding its effects on...Colitis-associated colorectal cancer(CAC)is a major contributor to cancer-related mortality worldwide.Titanium dioxide(TiO_(2),E171),a widely used food additive,has been insufficiently studied regarding its effects on macrophages within colon tumors during CAC development.In this study,CAC mouse models were used to investigate the biological impact of dietary E171 on macrophages in vivo,while lipopolysaccharide(LPS)-stimulated RAW264.7 macrophage cell lines were employed to elucidate the underlying mechanisms in vitro.We found that dietary E171 intake accelerated CAC development,exacerbated inflammatory responses and oxidative stress,and upregulated CAC-associated genes,including S100a8,S100a9,Lcn2,S100a11,Cxcl2,and interleukin-1α(Il-1α).E171 also increased the expression of S100A8,S100A9,NOD-like receptor family pyrin domain-containing 3(NLRP3),and gasdermin-D Nterminal(GSDMD-N)in macrophages within colon tumors.In inflammatory macrophages,E171 exposure enhanced cell viability,increased reactive oxygen species(ROS)levels,and elevated the expression and secretion of S100A8 and S100A9,consistent with in vivo histological observations.Furthermore,E171-induced secretion of S100A8 and S100A9 in macrophages was suppressed by specific inhibitors,including N-acetylcysteine(NAC,ROS inhibitor),MCC950(NLRP3 inhibitor),Z-YVAD-FMK(caspase 1 inhibitor),disulfiram(GSDMD inhibitor),and transfection of NLRP3 small interfering ribonucleic acid(siRNA).These results indicate that dietary E171 promotes CAC development by activating macrophages,with S100A8 and S100A9 serving as key mediators,and the NLRP3/caspase 1/GSDMD pathway acting as a critical mechanism.展开更多
Morphology and growth rate of carbon dioxide hydrate on the interface between liquid carbon dioxide and humic acid solutions were studied in this work.It was found that after the growth of the hydrate film at the inte...Morphology and growth rate of carbon dioxide hydrate on the interface between liquid carbon dioxide and humic acid solutions were studied in this work.It was found that after the growth of the hydrate film at the interface,further growth of hydrate due to the suction of water in the capillary system formed between the wall of the cuvette and the end boundary of the hydrate layer occurs.Most probably,substantial effects on the formation of this capillary system may be caused by variations in reactor wall properties,for example,hydrophobic-hydrophilic balance,roughness,etc.We found,that the rate of CO_(2) hydrate film growth on the surface of the humic acid aqueous solution is 4-fold to lower in comparison with the growth rate on the surface of pure water.We suppose that this is caused by the adsorption of humic acid associates on the surface of hydrate particles and,as a consequence,by the deceleration of the diffusion of dissolved carbon dioxide to the growing hydrate particle.展开更多
A single component molybdenum catalyst was synthesized and its activity in the cycloaddition reaction of CO_(2)and epoxide was tested.The results show that the molybdenum catalysts exhibit high activity and a broad su...A single component molybdenum catalyst was synthesized and its activity in the cycloaddition reaction of CO_(2)and epoxide was tested.The results show that the molybdenum catalysts exhibit high activity and a broad substrate scope under the reaction conditions of 80℃and 0.5 MPa of CO_(2),solvent-free,and and no nucleophilic cocatalysts,affording a wide range of cyclic carbonates in yields of 42%~94%.The reaction mechanism was investigated using in situ infrared(in situ IR),high-resolution mass spectrometry(HRMS)and Fourier transform infrared spectroscopy(FT-IR).展开更多
Confinement effect is an effective method to enhance carbon dioxide(CO_(2))solubility.In this study,a hybrid sorbent of 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([Hmim][NTf_2])/mesoporous titanium ...Confinement effect is an effective method to enhance carbon dioxide(CO_(2))solubility.In this study,a hybrid sorbent of 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([Hmim][NTf_2])/mesoporous titanium dioxide(M-TiO_(2))/water(H_2O)was developed,and its confinement effect was regulated by changing the pore structure of M-TiO_(2).CO_(2) solubility in the hybrid sorbent was measured experimentally,and the thermodynamic properties including Henry's constant and desorption enthalpy were calculated.Furthermore,the confinement effect in the hybrid sorbent was quantified.Additionally,the hybrid sorbent was recycled with a multi-cycle experiment.The results showed that M-TiO_(2) calcined at 773.2 K(MT500)could lead to an efficient confinement effect.CO_(2) solubility in the hybrid sorbent increased by 49.8%compared to that of H_2O when the mass fraction of[Hmim][NTf_2]/MT500 was 5.0%(mass),where the contribution of confinement effect on Gibbs free energy occupied 5.2%.展开更多
This study investigates the application of carbon dioxide (CO2) sequestration to address challenges in water-drive gas reservoirs, specifically focusing on improving gas recovery and mitigating water invasion. Traditi...This study investigates the application of carbon dioxide (CO2) sequestration to address challenges in water-drive gas reservoirs, specifically focusing on improving gas recovery and mitigating water invasion. Traditional methods like blow-down and co-production have limitations, including sand production, water coning, and inefficiency in strong aquifers. To overcome these issues, this research explores CO2 injection near the edge aquifer, aiming to reduce water influx and enhance gas recovery through the propagation of a CO2 plume in the gas-water contact zone. Both synthetic and real compositional reservoir models were studied, with CO2 injection performed while maintaining reservoir pressure below 90% of the initial level. Results show that CO2 sequestration significantly improved recovery, particularly in higher permeability reservoirs, where it reduced aquifer influx and increased gas production by 26% under challenging conditions. While CO2 dissolution in water decreased aquifer influx by 39%, its adverse effect on sweep efficiency led to a reduction in gas and water production by 4.2% and 10%, respectively. The method's effectiveness was not significantly impacted by aquifer permeability, but it was sensitive to vertical-to-horizontal permeability ratios. When applied to a real gas reservoir, the proposed method increased gas production by 14% compared to conventional techniques, with minimal CO2 production over a 112-year period. This study demonstrates the potential of CO2 sequestration as a comprehensive solution for enhancing gas recovery, reducing water production, and mitigating environmental impacts in water-drive gas reservoirs.展开更多
The photocatalytic reduction of CO_(2)is a crucial area of research aimed at addressing the dual challenges of mitigating rising CO_(2)emissions and producing sustainable chemical feedstocks.While multielectron reduct...The photocatalytic reduction of CO_(2)is a crucial area of research aimed at addressing the dual challenges of mitigating rising CO_(2)emissions and producing sustainable chemical feedstocks.While multielectron reduction pathways for CO_(2)are well explored,the single electron reduction to produce the highly reactive carbon dioxide radical anion(CO_(2)^(·-))remains challenging yet promising for green organic transformations.This review contributes to the field by providing a comprehensive analysis of the mechanisms,materials,and reaction pathways involved in CO_(2)^(·-)generation,focusing on the use of visible-lightdriven photocatalytic materials to circumvent the need for high-energy ultraviolet irradiation.Through a systematic examination of CO_(2)^(·-)production,detection methods,and chemical utilization in photocatalytic carboxylation reactions,this review advances understanding of the chemistry of CO_(2)^(·-)and its applications in sustainable chemical synthesis.In addition,it highlights existing key challenges,such as redox potential limitations,and proposes strategies for scaling up photocatalytic systems to enable practical application.By illuminating the pathway to effectively photocatalyze CO_(2)^(·-)generation and its transformative potential in sustainable chemical synthesis,this review equips scientists with critical insights and strategic approaches for overcoming current limitations,driving innovation in photocatalytic materials for solar-to-chemical energy conversion.展开更多
Mineral exploration under exotic overburden has been a great challenge in exploration geochemistry.Gas geochemical measurement is a potential method for mineral exploration due to the characteristics of strong penetra...Mineral exploration under exotic overburden has been a great challenge in exploration geochemistry.Gas geochemical measurement is a potential method for mineral exploration due to the characteristics of strong penetrability and vertical migration.The previous rapid gas analyzer cannot determine low concentrations of soil gases because of inadequate sensitivity,therefore,it is necessary to develop a more sensitive analytical technique.In this paper,the pilot studies on CO_(2) and SO_(2) geochemical measurements were performed at the Zhuxi W-(Cu)deposit,Jiapigou gold ore-concentrated area,and Tukuzbay gold deposit.This study employed rapid gas analyzer based on Infrared Absorption Spectroscopy and Electrochemical Analysis,which can detect low concentrations of CO_(2) and SO_(2) and greatly improve the reliability of test data.The results show that CO_(2) and SO_(2) show clear anomalies over deeply concealed ore bodies and faults,demonstrating that CO_(2) and SO_(2) anomalies can reveal indicative information about concealed mineralization and faults.Moreover,CO_(2) and SO_(2) anomalies can identify mineralization information exceeding 1,000 m in depth,suggesting that this method has large detection depth.Therefore,CO_(2) and SO_(2) geochemical measurement method is a feasible tool to discern deeply concealed mineralization and faults,and can provide a new idea in prospecting for concealed ore deposits in covered areas.展开更多
Using thermogravimetric experiments,the kinetic characteristics of magnesite thermal decomposition were investigated under the condition of 10%(vol) CO_(2) in the actual production atmosphere of an entrained-flow dyna...Using thermogravimetric experiments,the kinetic characteristics of magnesite thermal decomposition were investigated under the condition of 10%(vol) CO_(2) in the actual production atmosphere of an entrained-flow dynamic roasting furnace.Based on a multi-method collaborative framework,the three kinetic factors in the magnesite thermal decomposition process were systematically calculated through parameter cross-verification between the Hu-Gao-Zhang integral method and the Kissinger differential method.The kinetic mechanism was initially screened by the double equal and double step method and further determined by combining with the Malek maximum probability method.The study revealed that CO_(2) in the atmosphere exerts an inhibitory effect on the decomposition of carbonate species within magnesite.Furthermore,the presence of impurities(e.g.,calcium carbonate)was found to interfere with the determination of reaction mechanisms via Malek's method at elevated temperatures.The results show that in a 10%(vol)CO_(2)atmosphere,the main decomposition temperature of magnesite ranges from 550℃ to 650℃,the average activation energy is 66.00 k J·mol^(-1),the pre-exponential factor is 1.05×10^(5)s^(-1),and the decomposition process conforms to the random nucleation and growth model.展开更多
Laparoscopic liver resection(LLR)is currently the first-linetreatment for multiple liver diseases.Although clinical data have proven its safety and effectiveness,bleeding and carbon dioxide(CO_(2))embolism are still t...Laparoscopic liver resection(LLR)is currently the first-linetreatment for multiple liver diseases.Although clinical data have proven its safety and effectiveness,bleeding and carbon dioxide(CO_(2))embolism are still the major complications of LLR.The objective of this review was to summarize the pathogenetic mechanism,clinical manifestations,risk factors,prophylactic measures,and treatment strategies for CO_(2) embolism in LLR and propose further research directions regarding these controversial issues.A narrative review of the literature from three databases,including PubMed,Embase,and Web of Science,was conducted without any date or language restrictions.The search terms included CO_(2) embolism,gas embolism,laparoscopy,liver resection,and hepatectomy.The incidence of CO_(2) embolism in LLR(1.2%–4.6%)is approximately 10 times greater than that in overall laparoscopic surgery(0.15%).Transesophageal echocardiogram is currently considered the gold standard for identifying CO_(2) embolism.Risk factors are multifactorial and involve patient characteristics,procedural techniques,and anesthetic management.Presently,in clinical practice,a pneumoperitoneal pressure of 10–15 mmHg is typically used to balance bleeding and CO_(2) embolism during LLR.The majority of observed CO_(2) embolism events are benign,with no significantclinical impact on short-term or long-term outcomes.However,meticulous monitoring,timely recognition,and prompt intervention are crucial during LLR to prevent life-threatening events.Future research should further refinerisk stratification,validate early detection methods,and develop standardized management protocols for CO_(2) embolism in LLR.展开更多
Carbon dioxide photocatalytic reduction (CO_(2)-PR) is an efficient method for controlling CO_(2)emissions and generating cleaner energy while mitigating global warming.Tungsten oxides (WxOy) have attracted considerab...Carbon dioxide photocatalytic reduction (CO_(2)-PR) is an efficient method for controlling CO_(2)emissions and generating cleaner energy while mitigating global warming.Tungsten oxides (WxOy) have attracted considerable attention for CO_(2)-PR due to their excellent spectral absorbance.However,comprehensive reviews are lacking on the use of WxOyfor CO_(2)-PR.Therefore,this review provides a detailed summary of t research progress made with WxOy-based catalysts in CO_(2)-PR.It also explains the fundamental principles of CO_(2)-PR and evaluates key performance indicators that affect the activity of WxOy-based photocatalysts,including yield,selectivity,stability,and apparent quantum yield.Additionally,this review explores opportunities for synthesizing high-performance WxOy-based photocatalysts and highlights their potential for the green preparation of C1/C2 products through CO_(2)-PR.These innovative strategies aim to address the challenges and pressures associated with energy and environmental issues,particularly by enhancing artificial photosynthesis efficiency.展开更多
Dimensionality has great influence on the photo/electro-catalysts properties of covalent organic frameworks(COFs) because of the different electronic and porous structures.However,very rare attention has been paid on ...Dimensionality has great influence on the photo/electro-catalysts properties of covalent organic frameworks(COFs) because of the different electronic and porous structures.However,very rare attention has been paid on the dimensionality and function correlations of COF materials.In the present work,one new two-dimensional phthalocyanine COF,namely 2D-NiPc-COF,and one new three-dimensional phthalocyanine COF,namely 3D-NiPc-COF,were fabricated according to the imide reaction between tetraanhydrides of 2,3,9,10,16,17,23,24-octacarboxyphthalocyaninato nickel(Ⅱ) with [2,2-bipyridine]-5,5-diamine and tetrakis(4-aminophenyl) methane,respectively.The crystalline structures of both COFs are verified by the powder X-ray diffraction analysis,computational simulation,and high resolution transmission electron microscopy measurement.Notably,3D-NiPc-COF with dispersed conjugated modules has high utilization efficiency of NiPc electroactive sites of 26.8%,almost two times higher than the in-plane stacking2D-NiPc-COF measured by electrochemical measurement,in turn resulting in its superior electrocatalytic performance with high CO_(2)-to-CO Faradaic efficiency over 90% in a wide potential window,a large partial CO current density of-13.97 mA/cm^(2) at-0.9 V(vs.reversible hydrogen electrode) to 2D-NiPc-COF.Moreover,3D-NiPc-COF has higher turnover number and turnover frequency of 5741.6 and 0.18 s^(-1) at-0.8 V during 8 h lasting measurement.The present work provides an example for the investigation on the correlation between dimensionality and electrochemical properties of 2D and 3D phthalocyanine COFs.展开更多
Concrete is one of the key component in the construction field.The importance of concrete is because of its strength and long lasting properties.The incorporation of nano materials in concrete helps to improve the cha...Concrete is one of the key component in the construction field.The importance of concrete is because of its strength and long lasting properties.The incorporation of nano materials in concrete helps to improve the characteristics of conventional concrete.Titanium dioxide(TiO_(2))is one such nanomaterial that helps to increase the performance of concrete by enhancing self-cleaning,anti-microbial and anti-bacterial activities.This paper briefly explains about the reaction of titanium dioxide nano particle N-TiO_(2) on cement materials which in turn changes the mechanical and physical properties of concrete against chemical,climatic changes and abrasion.The review presented here includes the features of titanium dioxide nano particles basically,its dosage in concrete,its impact on concrete on both fresh and hardened properties,photo catalytic effect and anti-microbial.This review explores the photo catalytic degradation of concrete enhanced with N-TiO_(2),which presents a promising method for improving the durability and sustainability of concrete structures.The addition of N-TiO_(2),recognized for its photo catalytic properties when exposed to UV light,has demonstrated potential in tackling various environmental and structural challenges associated with concrete.The paper provides a detailed analysis of the mechanisms involved in the photo catalytic process,the way N-TiO_(2) particles aid in breaking down pollutants(including organic compounds,NOx,and CO₂),and its contributions to self-cleaning,antimicrobial functions,and the degradation of harmful pollutants.展开更多
In response to the fact that the presence of manganese dithionate(MnS_(2)O_(6))leads to a series of adverse impacts,especially lower purity of manganese sulfate(MnSO_(4))and disruption of its recovery,advanced oxidati...In response to the fact that the presence of manganese dithionate(MnS_(2)O_(6))leads to a series of adverse impacts,especially lower purity of manganese sulfate(MnSO_(4))and disruption of its recovery,advanced oxidation methods such as ozonation system are used to manage MnS_(2)O_(6)in the leaching solution,replacing conventional methods.To ascertain the conversion rate and kinetics of MnS_(2)O_(6)during the ozonation process,we explored the factors influencing its removal rate,including ozone dosage,manganese dithionate concentration,sulfuric acid concentration,and reaction temperature.Batch experiments were conducted to determine the reaction rate constant of ozone(k)and activation energy(Ea)obtained from intermittent experimental data fitting,revealing a least-squares exponential conversion relationship between k and the MnS_(2)O_(6)removal amount,wherein an increase in the aforementioned factors led to an enhanced MnS_(2)O_(6)conversion rate,exceeding 99.3%.The formation mechanism of the ozone products proposed during the experiment was summarized and proposed as follows:1)Mn^(2+)was directly oxidized to MnO_(2),and 2)SO_(4)2−was obtained by the catalytic oxidation of S_(2)O_(6)^(2−)with HO•from O3 decomposition.According to the kinetics analysis,the pre-exponential factor and total activation energy of the ozonation kinetics equation were 1.0×10^(23) s^(−1) and 177.28 kJ/mol,respectively.Overall,the present study demonstrates that O_(3) as an oxidizing agent can effectively facilitate MnS_(2)O_(6)disproportionation while preventing the release of the secondary pollutant,SO_(2)gas.展开更多
This study synthesizes and evaluates a novel polysulfone-based membrane doped with graphene oxidepolyethyleneimine-silicon oxide(GO-SiO_(2)-PEI),specifically designed for oily water treatment applications.The function...This study synthesizes and evaluates a novel polysulfone-based membrane doped with graphene oxidepolyethyleneimine-silicon oxide(GO-SiO_(2)-PEI),specifically designed for oily water treatment applications.The functionalization of graphene oxide with SiO_(2) and PEI was rigorously confirmed through comprehensive XRD,FTIR,Raman spectroscopy,and XPS analyses,ensuring the integrity and expected functionality of the nanocomposite.This nanocomposite was integrated into the polysulfone(PSF)membrane matrix,significantly reducing the membrane's inherent hydrophobicity and propensity for fouling.The membranes were meticulously characterized using advanced surface and bulk sensitive apparatus including contact angle and SEM imaging to ascertain their structural and functional attributes.Performance evaluations conducted in a dead-end filtration setup revealed that incorporating 1.0%(mass) of the nanocomposite into the PSF membrane markedly enhanced its porosity and improved the water contact angle.This modification led to an 809% increase in the membrane's water flux and a 57%enhancement in flux recovery rate,while still maintaining a high oil rejection rate and a relatively low leaching rate of 5.3 mg·L^(-1).Analysis through the Owens-Wendt-Kaelble model indicated a significant increase in polar surface energy,corroborating the improved oil rejection capabilities at elevated flux levels.Fouling behavior,analyzed using Hermia's model,identified cake formation as the primary fouling mechanism in most of the tested membranes.Leaching tests further highlighted those membranes with higher nanocomposite loadings exhibited increased leaching rates,suggesting a trade-off between performance enhancement and material stability.展开更多
The calcium-containing rare earth solution is generated during the recovery processes of NdFeB waste,which is treated as wastewater by enterprises.In this paper,the carbon dioxide carbonization method was applied to t...The calcium-containing rare earth solution is generated during the recovery processes of NdFeB waste,which is treated as wastewater by enterprises.In this paper,the carbon dioxide carbonization method was applied to the separation of rare earths and calcium in the solution,as well as the preparation of rare earth oxides with a large specific surface.It is shown that the process of CO_(2)carbonization of solution includes reactions such as the dissolution,diffusion and ionization of CO_(2),the carbonate precipitation of rare earth ions,and the neutralization of hydrogen ions.At a pH of 4.5,the carbonization precipitation rate is effectively controlled,enabling homogeneous precipitation and ensuring both high precipitation yield and rare earth oxides purity.In this way,the crystallization of carbonization products is a process dominated by the oriented attachment theory and coexisting with the Ostwald ripening theory,resulting in abundant pores formed by multiple layers of stacking in the products.With the optimal carbonization conditions,the rare earth precipitation yield solution reaches 99.32%.The obtained carbonization products are crystalline(LaCe)(CO_(3))_(3)·8H_(2)O,and the purity of the rare earth oxides is as high as 99.22 wt%.The specific surface area of the rare earth oxides reaches 94.7 m^(2)/g,and its adsorption efficiency for tetracycline hydrochloride in solution can reach 92.6%in a short time.The rare earth oxides are expected to be used as an adsorption material for wastewater treatment and other adsorption environments.展开更多
The absorption of air pollutants is an indicator for studying the value of forest land.It plays an important role in compiling resource balance sheets by studying the absorption of air pollutants by forest land.This p...The absorption of air pollutants is an indicator for studying the value of forest land.It plays an important role in compiling resource balance sheets by studying the absorption of air pollutants by forest land.This paper focused on sulfur dioxide,an air pollutant.Through on-site air sample collection and laboratory testing,using the calculation method of the UFORE model issued by the US Forestry Administration,the annual absorption data of sulfur dioxide in different forest lands in Dapeng New Area were obtained.The results showed that there was not much difference in the absorption capacity of sulfur dioxide among the three types of forest lands in the new area:shrubland,broad-leaved forest,and artificial forest.The amount of sulfur dioxide absorbed per unit area ranged from 11.80 to 13.62 kg/(hm^(2)·a).However,coniferous forests had a lower absorption capacity for sulfur dioxide,with an absorption per unit area of 5.39 kg/(hm^(2)·a).展开更多
A strategy for copper-catalyzed and biphosphine ligand controlled boracarboxylation of 1,3-dienes and CO_(2) with 3,4-selectivity was developed.The Cu Cl coupled with DPPF(1,1-bis(diphenylphosphino)ferrocene)was assig...A strategy for copper-catalyzed and biphosphine ligand controlled boracarboxylation of 1,3-dienes and CO_(2) with 3,4-selectivity was developed.The Cu Cl coupled with DPPF(1,1-bis(diphenylphosphino)ferrocene)was assigned to be the best catalyst,with 84%yield and exclusive3,4-selectivity.The ligand effect on both catalytic activity and regioselectivity of boracarboxylation was disclosed,which is rarely reported in any copper catalyzed boracarboxylation.The borocupration process is revealed to be a vital step for the biphosphine participated boracarboxylation of 1,3-dienes with CO_(2).The minimal substrate distortion occurring in 3,4-borocupration favors the 3,4-regioselectivity of boracarboxylation.The“pocket”confinement and suitableβ_(n)(92°–106°)of bisphosphine ligands are demonstrated to be in favour of the interaction between LCu-Bpin complex(the catalytic precursor)and1,3-diene substrate to decrease their interaction energyΔE_(int)(ζ)in 3,4-borocupration,thus promoting the 3,4-boracarboxylation.展开更多
Endotracheal intubation has broad application prospects in the biomedical field.At present,visual intubation tools are mainly used to judge the catheter position.However,when patients suffer from pains in the neck,thr...Endotracheal intubation has broad application prospects in the biomedical field.At present,visual intubation tools are mainly used to judge the catheter position.However,when patients suffer from pains in the neck,throat,and trachea and other diseases or other conditions,if the exposure of the glottic area is not ideal,there are difficult airways.For difficult airways,this visual intubation tool has great limitations.Studying the new guidance method of endotracheal intubation and providing a reference or solution for difficult airway intubation is a crucial problem in the biomedical clinical field.In this paper,an endotracheal intubation method is proposed based on end-tidal carbon dioxide(ETCO_(2))perception.The simulation model verifies the feasibility of this method for endotracheal intubation guidance.Then,four micro-cavity tubes are used as a gas collection tube,and a set of endotracheal tube guidance systems based on ETCO_(2) perception is designed and developed to collect and process the CO_(2) concentration information in the pharyngeal cavity.The experimental results show that this guidance system can be used for intubation guidance in the simulated pharyngeal cavity without vision.展开更多
Strong Coulombic repulsion in small doubly charged molecular ions usually leads to fragmentation.Some of these ions,such as CO_(2)^(++),could survive and be detected if they are stable or metastable in energetics,but ...Strong Coulombic repulsion in small doubly charged molecular ions usually leads to fragmentation.Some of these ions,such as CO_(2)^(++),could survive and be detected if they are stable or metastable in energetics,but how to produce these observable doubly charged ions is a puzzling issue.Here we investigate CO_(2)^(++)production by electron-impact ionization with a supersonic molecular beam of CO_(2)under different nozzle pressures,using time-of-flight mass spectrometry measurements and ab initio calculations.The mass spectral profile of CO_(2)^(++)varies slightly with the nozzle pressure,implying different mechanisms of the ion production.The calculations indicate that the ground state of CO_(2)^(++)is 3Aʺwith a nonlinear conformation,while the linear conformer is in the first excited state 1Δ_(g).We further suggest that,besides CO_(2)^(++)(1Δ_(g))produced from CO_(2),CO_(2)^(++)(3Aʺ)could be produced by the dissociation of doubly charged dimer(C2O4^(++))in a repulsive triplet state.展开更多
Interlayer engineering of two-dimensional structural materials provides unique advantages for tuning the electromagnetic properties of metal oxides,injecting unlimited energy into the design of advanced two-dimensiona...Interlayer engineering of two-dimensional structural materials provides unique advantages for tuning the electromagnetic properties of metal oxides,injecting unlimited energy into the design of advanced two-dimensional metal oxide electromagnetic wave absorbers.In this study,Manganese dioxide intercalated with alkali metal ions was prepared by a simple molten salt method.The pre-intercalation of ions not only enhances the polarization loss at the heterogeneous interface between cations(point sites)and man-ganese dioxide(face sites)but also alters the energy band structure of manganese oxide and enhances its electrical conductivity,which in turn enhances the conductive loss of the manganese dioxide.Due to the synergistic effect of multiple polarizations and conductive losses,NaMO exhibits superb electromag-netic wave absorption properties and an effective absorption bandwidth of 5.36 GHz at thinner matched thicknesses.In addition,the RCS simulation result further verifies the excellent electromagnetic wave ab-sorption capability of NaMO.Under the positive incidence of electromagnetic waves,the electromagnetic wave reflection intensity of the metal plate coated with NaMO is effectively reduced.Finally,this work establishes a new way to modulate the electromagnetic properties.展开更多
基金supported by the National Natural Science Foundation of China(Nos.81974441 and 82203619)the Science and Technology Planning Project of Shenzhen Municipality(Nos.JCYJ20190814105619048 and JCYJ20220530154202005)。
文摘Colitis-associated colorectal cancer(CAC)is a major contributor to cancer-related mortality worldwide.Titanium dioxide(TiO_(2),E171),a widely used food additive,has been insufficiently studied regarding its effects on macrophages within colon tumors during CAC development.In this study,CAC mouse models were used to investigate the biological impact of dietary E171 on macrophages in vivo,while lipopolysaccharide(LPS)-stimulated RAW264.7 macrophage cell lines were employed to elucidate the underlying mechanisms in vitro.We found that dietary E171 intake accelerated CAC development,exacerbated inflammatory responses and oxidative stress,and upregulated CAC-associated genes,including S100a8,S100a9,Lcn2,S100a11,Cxcl2,and interleukin-1α(Il-1α).E171 also increased the expression of S100A8,S100A9,NOD-like receptor family pyrin domain-containing 3(NLRP3),and gasdermin-D Nterminal(GSDMD-N)in macrophages within colon tumors.In inflammatory macrophages,E171 exposure enhanced cell viability,increased reactive oxygen species(ROS)levels,and elevated the expression and secretion of S100A8 and S100A9,consistent with in vivo histological observations.Furthermore,E171-induced secretion of S100A8 and S100A9 in macrophages was suppressed by specific inhibitors,including N-acetylcysteine(NAC,ROS inhibitor),MCC950(NLRP3 inhibitor),Z-YVAD-FMK(caspase 1 inhibitor),disulfiram(GSDMD inhibitor),and transfection of NLRP3 small interfering ribonucleic acid(siRNA).These results indicate that dietary E171 promotes CAC development by activating macrophages,with S100A8 and S100A9 serving as key mediators,and the NLRP3/caspase 1/GSDMD pathway acting as a critical mechanism.
基金supported by the Russian Science Foundation(23-29-00830).
文摘Morphology and growth rate of carbon dioxide hydrate on the interface between liquid carbon dioxide and humic acid solutions were studied in this work.It was found that after the growth of the hydrate film at the interface,further growth of hydrate due to the suction of water in the capillary system formed between the wall of the cuvette and the end boundary of the hydrate layer occurs.Most probably,substantial effects on the formation of this capillary system may be caused by variations in reactor wall properties,for example,hydrophobic-hydrophilic balance,roughness,etc.We found,that the rate of CO_(2) hydrate film growth on the surface of the humic acid aqueous solution is 4-fold to lower in comparison with the growth rate on the surface of pure water.We suppose that this is caused by the adsorption of humic acid associates on the surface of hydrate particles and,as a consequence,by the deceleration of the diffusion of dissolved carbon dioxide to the growing hydrate particle.
文摘A single component molybdenum catalyst was synthesized and its activity in the cycloaddition reaction of CO_(2)and epoxide was tested.The results show that the molybdenum catalysts exhibit high activity and a broad substrate scope under the reaction conditions of 80℃and 0.5 MPa of CO_(2),solvent-free,and and no nucleophilic cocatalysts,affording a wide range of cyclic carbonates in yields of 42%~94%.The reaction mechanism was investigated using in situ infrared(in situ IR),high-resolution mass spectrometry(HRMS)and Fourier transform infrared spectroscopy(FT-IR).
基金the National Natural Science Foundation of China(22108115,22478415,and 21978134)Natural Science Foundation of Jiangsu Province(BK20241744)。
文摘Confinement effect is an effective method to enhance carbon dioxide(CO_(2))solubility.In this study,a hybrid sorbent of 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([Hmim][NTf_2])/mesoporous titanium dioxide(M-TiO_(2))/water(H_2O)was developed,and its confinement effect was regulated by changing the pore structure of M-TiO_(2).CO_(2) solubility in the hybrid sorbent was measured experimentally,and the thermodynamic properties including Henry's constant and desorption enthalpy were calculated.Furthermore,the confinement effect in the hybrid sorbent was quantified.Additionally,the hybrid sorbent was recycled with a multi-cycle experiment.The results showed that M-TiO_(2) calcined at 773.2 K(MT500)could lead to an efficient confinement effect.CO_(2) solubility in the hybrid sorbent increased by 49.8%compared to that of H_2O when the mass fraction of[Hmim][NTf_2]/MT500 was 5.0%(mass),where the contribution of confinement effect on Gibbs free energy occupied 5.2%.
文摘This study investigates the application of carbon dioxide (CO2) sequestration to address challenges in water-drive gas reservoirs, specifically focusing on improving gas recovery and mitigating water invasion. Traditional methods like blow-down and co-production have limitations, including sand production, water coning, and inefficiency in strong aquifers. To overcome these issues, this research explores CO2 injection near the edge aquifer, aiming to reduce water influx and enhance gas recovery through the propagation of a CO2 plume in the gas-water contact zone. Both synthetic and real compositional reservoir models were studied, with CO2 injection performed while maintaining reservoir pressure below 90% of the initial level. Results show that CO2 sequestration significantly improved recovery, particularly in higher permeability reservoirs, where it reduced aquifer influx and increased gas production by 26% under challenging conditions. While CO2 dissolution in water decreased aquifer influx by 39%, its adverse effect on sweep efficiency led to a reduction in gas and water production by 4.2% and 10%, respectively. The method's effectiveness was not significantly impacted by aquifer permeability, but it was sensitive to vertical-to-horizontal permeability ratios. When applied to a real gas reservoir, the proposed method increased gas production by 14% compared to conventional techniques, with minimal CO2 production over a 112-year period. This study demonstrates the potential of CO2 sequestration as a comprehensive solution for enhancing gas recovery, reducing water production, and mitigating environmental impacts in water-drive gas reservoirs.
基金funding programs,the Walter Benjamin Programme(DFG,German Research Foundation,project number:530742479)the ProChancecareer Programme for the Promotion of Equal Opportunities in Academia for providing the financial support+1 种基金financial support by the Deutsche Forschungsgemeinschaft via the TRR 234 Cata Light(DFG,German Research Foundation)-Projektnummer 364549901-TRR 234[B6]the financial support taken from the CSIR and UGC,Delhi,India。
文摘The photocatalytic reduction of CO_(2)is a crucial area of research aimed at addressing the dual challenges of mitigating rising CO_(2)emissions and producing sustainable chemical feedstocks.While multielectron reduction pathways for CO_(2)are well explored,the single electron reduction to produce the highly reactive carbon dioxide radical anion(CO_(2)^(·-))remains challenging yet promising for green organic transformations.This review contributes to the field by providing a comprehensive analysis of the mechanisms,materials,and reaction pathways involved in CO_(2)^(·-)generation,focusing on the use of visible-lightdriven photocatalytic materials to circumvent the need for high-energy ultraviolet irradiation.Through a systematic examination of CO_(2)^(·-)production,detection methods,and chemical utilization in photocatalytic carboxylation reactions,this review advances understanding of the chemistry of CO_(2)^(·-)and its applications in sustainable chemical synthesis.In addition,it highlights existing key challenges,such as redox potential limitations,and proposes strategies for scaling up photocatalytic systems to enable practical application.By illuminating the pathway to effectively photocatalyze CO_(2)^(·-)generation and its transformative potential in sustainable chemical synthesis,this review equips scientists with critical insights and strategic approaches for overcoming current limitations,driving innovation in photocatalytic materials for solar-to-chemical energy conversion.
基金the Key Laboratory of Geochemical Exploration, Institute of Geophysical and Geochemical Exploration, China Geological Survey, and Ministry of Natural Resources of the People’s Republic of China for funding this researchsupported by National Nonprofit Institute Research Grant of Institute of Geophysical and Geochemical Exploration (AS2022P03)Key Laboratory of Ionic Rare Earth Resources and Environment, Ministry of Natural Resources of the People’s Republic of China (No. 2022IRERE101 and No. 2023IRERE102)
文摘Mineral exploration under exotic overburden has been a great challenge in exploration geochemistry.Gas geochemical measurement is a potential method for mineral exploration due to the characteristics of strong penetrability and vertical migration.The previous rapid gas analyzer cannot determine low concentrations of soil gases because of inadequate sensitivity,therefore,it is necessary to develop a more sensitive analytical technique.In this paper,the pilot studies on CO_(2) and SO_(2) geochemical measurements were performed at the Zhuxi W-(Cu)deposit,Jiapigou gold ore-concentrated area,and Tukuzbay gold deposit.This study employed rapid gas analyzer based on Infrared Absorption Spectroscopy and Electrochemical Analysis,which can detect low concentrations of CO_(2) and SO_(2) and greatly improve the reliability of test data.The results show that CO_(2) and SO_(2) show clear anomalies over deeply concealed ore bodies and faults,demonstrating that CO_(2) and SO_(2) anomalies can reveal indicative information about concealed mineralization and faults.Moreover,CO_(2) and SO_(2) anomalies can identify mineralization information exceeding 1,000 m in depth,suggesting that this method has large detection depth.Therefore,CO_(2) and SO_(2) geochemical measurement method is a feasible tool to discern deeply concealed mineralization and faults,and can provide a new idea in prospecting for concealed ore deposits in covered areas.
基金supported by the Natural Science Foundation of Liaoning Province(2024-MSLH-360)。
文摘Using thermogravimetric experiments,the kinetic characteristics of magnesite thermal decomposition were investigated under the condition of 10%(vol) CO_(2) in the actual production atmosphere of an entrained-flow dynamic roasting furnace.Based on a multi-method collaborative framework,the three kinetic factors in the magnesite thermal decomposition process were systematically calculated through parameter cross-verification between the Hu-Gao-Zhang integral method and the Kissinger differential method.The kinetic mechanism was initially screened by the double equal and double step method and further determined by combining with the Malek maximum probability method.The study revealed that CO_(2) in the atmosphere exerts an inhibitory effect on the decomposition of carbonate species within magnesite.Furthermore,the presence of impurities(e.g.,calcium carbonate)was found to interfere with the determination of reaction mechanisms via Malek's method at elevated temperatures.The results show that in a 10%(vol)CO_(2)atmosphere,the main decomposition temperature of magnesite ranges from 550℃ to 650℃,the average activation energy is 66.00 k J·mol^(-1),the pre-exponential factor is 1.05×10^(5)s^(-1),and the decomposition process conforms to the random nucleation and growth model.
基金supported by grants from the Science and Technology Program of Zhejiang Province(Nos.2024C03201,2025C02133)the Central Government Guides Local Science and Technology Development Fund Projects(No.2024ZY01020).
文摘Laparoscopic liver resection(LLR)is currently the first-linetreatment for multiple liver diseases.Although clinical data have proven its safety and effectiveness,bleeding and carbon dioxide(CO_(2))embolism are still the major complications of LLR.The objective of this review was to summarize the pathogenetic mechanism,clinical manifestations,risk factors,prophylactic measures,and treatment strategies for CO_(2) embolism in LLR and propose further research directions regarding these controversial issues.A narrative review of the literature from three databases,including PubMed,Embase,and Web of Science,was conducted without any date or language restrictions.The search terms included CO_(2) embolism,gas embolism,laparoscopy,liver resection,and hepatectomy.The incidence of CO_(2) embolism in LLR(1.2%–4.6%)is approximately 10 times greater than that in overall laparoscopic surgery(0.15%).Transesophageal echocardiogram is currently considered the gold standard for identifying CO_(2) embolism.Risk factors are multifactorial and involve patient characteristics,procedural techniques,and anesthetic management.Presently,in clinical practice,a pneumoperitoneal pressure of 10–15 mmHg is typically used to balance bleeding and CO_(2) embolism during LLR.The majority of observed CO_(2) embolism events are benign,with no significantclinical impact on short-term or long-term outcomes.However,meticulous monitoring,timely recognition,and prompt intervention are crucial during LLR to prevent life-threatening events.Future research should further refinerisk stratification,validate early detection methods,and develop standardized management protocols for CO_(2) embolism in LLR.
基金supported by the National Natural Science Foundation of China(No.22376065)the Science and Technology Commission of Shanghai Municipality(No.22ZR1418600)Shanghai Municipal Science and Technology(No.20DZ2250400)。
文摘Carbon dioxide photocatalytic reduction (CO_(2)-PR) is an efficient method for controlling CO_(2)emissions and generating cleaner energy while mitigating global warming.Tungsten oxides (WxOy) have attracted considerable attention for CO_(2)-PR due to their excellent spectral absorbance.However,comprehensive reviews are lacking on the use of WxOyfor CO_(2)-PR.Therefore,this review provides a detailed summary of t research progress made with WxOy-based catalysts in CO_(2)-PR.It also explains the fundamental principles of CO_(2)-PR and evaluates key performance indicators that affect the activity of WxOy-based photocatalysts,including yield,selectivity,stability,and apparent quantum yield.Additionally,this review explores opportunities for synthesizing high-performance WxOy-based photocatalysts and highlights their potential for the green preparation of C1/C2 products through CO_(2)-PR.These innovative strategies aim to address the challenges and pressures associated with energy and environmental issues,particularly by enhancing artificial photosynthesis efficiency.
基金Financial support from the Natural Science Foundation(NSF) of China(Nos.22205015,22175020,and 22235001)the National Postdoctoral Program for Innovative Talents(No.BX20220032)+1 种基金the China Postdoctoral Science Foundation Funded Project(No.2022BG013)the Fundamental Research Funds for the Central Universities(Nos.00007709 and 00007770)。
文摘Dimensionality has great influence on the photo/electro-catalysts properties of covalent organic frameworks(COFs) because of the different electronic and porous structures.However,very rare attention has been paid on the dimensionality and function correlations of COF materials.In the present work,one new two-dimensional phthalocyanine COF,namely 2D-NiPc-COF,and one new three-dimensional phthalocyanine COF,namely 3D-NiPc-COF,were fabricated according to the imide reaction between tetraanhydrides of 2,3,9,10,16,17,23,24-octacarboxyphthalocyaninato nickel(Ⅱ) with [2,2-bipyridine]-5,5-diamine and tetrakis(4-aminophenyl) methane,respectively.The crystalline structures of both COFs are verified by the powder X-ray diffraction analysis,computational simulation,and high resolution transmission electron microscopy measurement.Notably,3D-NiPc-COF with dispersed conjugated modules has high utilization efficiency of NiPc electroactive sites of 26.8%,almost two times higher than the in-plane stacking2D-NiPc-COF measured by electrochemical measurement,in turn resulting in its superior electrocatalytic performance with high CO_(2)-to-CO Faradaic efficiency over 90% in a wide potential window,a large partial CO current density of-13.97 mA/cm^(2) at-0.9 V(vs.reversible hydrogen electrode) to 2D-NiPc-COF.Moreover,3D-NiPc-COF has higher turnover number and turnover frequency of 5741.6 and 0.18 s^(-1) at-0.8 V during 8 h lasting measurement.The present work provides an example for the investigation on the correlation between dimensionality and electrochemical properties of 2D and 3D phthalocyanine COFs.
文摘Concrete is one of the key component in the construction field.The importance of concrete is because of its strength and long lasting properties.The incorporation of nano materials in concrete helps to improve the characteristics of conventional concrete.Titanium dioxide(TiO_(2))is one such nanomaterial that helps to increase the performance of concrete by enhancing self-cleaning,anti-microbial and anti-bacterial activities.This paper briefly explains about the reaction of titanium dioxide nano particle N-TiO_(2) on cement materials which in turn changes the mechanical and physical properties of concrete against chemical,climatic changes and abrasion.The review presented here includes the features of titanium dioxide nano particles basically,its dosage in concrete,its impact on concrete on both fresh and hardened properties,photo catalytic effect and anti-microbial.This review explores the photo catalytic degradation of concrete enhanced with N-TiO_(2),which presents a promising method for improving the durability and sustainability of concrete structures.The addition of N-TiO_(2),recognized for its photo catalytic properties when exposed to UV light,has demonstrated potential in tackling various environmental and structural challenges associated with concrete.The paper provides a detailed analysis of the mechanisms involved in the photo catalytic process,the way N-TiO_(2) particles aid in breaking down pollutants(including organic compounds,NOx,and CO₂),and its contributions to self-cleaning,antimicrobial functions,and the degradation of harmful pollutants.
基金Project(2022M710619)supported by the Postdoctoral Science Foundation of ChinaProjects(2020YFH0213,2020YFG0039)supported by the Sichuan Science and Technology Program,China+1 种基金Projects(XJ2024001501,KCXTD2023-4)supported by the Basic Scientific Foundation and Innovation Team Funds of China West Normal UniversityProject(CSPC202403)supported by the Open Project Program of Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province,China。
文摘In response to the fact that the presence of manganese dithionate(MnS_(2)O_(6))leads to a series of adverse impacts,especially lower purity of manganese sulfate(MnSO_(4))and disruption of its recovery,advanced oxidation methods such as ozonation system are used to manage MnS_(2)O_(6)in the leaching solution,replacing conventional methods.To ascertain the conversion rate and kinetics of MnS_(2)O_(6)during the ozonation process,we explored the factors influencing its removal rate,including ozone dosage,manganese dithionate concentration,sulfuric acid concentration,and reaction temperature.Batch experiments were conducted to determine the reaction rate constant of ozone(k)and activation energy(Ea)obtained from intermittent experimental data fitting,revealing a least-squares exponential conversion relationship between k and the MnS_(2)O_(6)removal amount,wherein an increase in the aforementioned factors led to an enhanced MnS_(2)O_(6)conversion rate,exceeding 99.3%.The formation mechanism of the ozone products proposed during the experiment was summarized and proposed as follows:1)Mn^(2+)was directly oxidized to MnO_(2),and 2)SO_(4)2−was obtained by the catalytic oxidation of S_(2)O_(6)^(2−)with HO•from O3 decomposition.According to the kinetics analysis,the pre-exponential factor and total activation energy of the ozonation kinetics equation were 1.0×10^(23) s^(−1) and 177.28 kJ/mol,respectively.Overall,the present study demonstrates that O_(3) as an oxidizing agent can effectively facilitate MnS_(2)O_(6)disproportionation while preventing the release of the secondary pollutant,SO_(2)gas.
基金made possible by Qatar University internal grant(i-GA-379)graduate sponsorship research award (GSRA7-1-0510-20046) from Qatar National Research Fund (QNRF)。
文摘This study synthesizes and evaluates a novel polysulfone-based membrane doped with graphene oxidepolyethyleneimine-silicon oxide(GO-SiO_(2)-PEI),specifically designed for oily water treatment applications.The functionalization of graphene oxide with SiO_(2) and PEI was rigorously confirmed through comprehensive XRD,FTIR,Raman spectroscopy,and XPS analyses,ensuring the integrity and expected functionality of the nanocomposite.This nanocomposite was integrated into the polysulfone(PSF)membrane matrix,significantly reducing the membrane's inherent hydrophobicity and propensity for fouling.The membranes were meticulously characterized using advanced surface and bulk sensitive apparatus including contact angle and SEM imaging to ascertain their structural and functional attributes.Performance evaluations conducted in a dead-end filtration setup revealed that incorporating 1.0%(mass) of the nanocomposite into the PSF membrane markedly enhanced its porosity and improved the water contact angle.This modification led to an 809% increase in the membrane's water flux and a 57%enhancement in flux recovery rate,while still maintaining a high oil rejection rate and a relatively low leaching rate of 5.3 mg·L^(-1).Analysis through the Owens-Wendt-Kaelble model indicated a significant increase in polar surface energy,corroborating the improved oil rejection capabilities at elevated flux levels.Fouling behavior,analyzed using Hermia's model,identified cake formation as the primary fouling mechanism in most of the tested membranes.Leaching tests further highlighted those membranes with higher nanocomposite loadings exhibited increased leaching rates,suggesting a trade-off between performance enhancement and material stability.
基金Project supported by the National Key Research and Development Project of China(2022YFC2905202)Natural Science Foundation of Jiangxi Province(20232ACB204014)Youth Jinggang Scholars Program in Jiangxi Province(QNJG2019056)。
文摘The calcium-containing rare earth solution is generated during the recovery processes of NdFeB waste,which is treated as wastewater by enterprises.In this paper,the carbon dioxide carbonization method was applied to the separation of rare earths and calcium in the solution,as well as the preparation of rare earth oxides with a large specific surface.It is shown that the process of CO_(2)carbonization of solution includes reactions such as the dissolution,diffusion and ionization of CO_(2),the carbonate precipitation of rare earth ions,and the neutralization of hydrogen ions.At a pH of 4.5,the carbonization precipitation rate is effectively controlled,enabling homogeneous precipitation and ensuring both high precipitation yield and rare earth oxides purity.In this way,the crystallization of carbonization products is a process dominated by the oriented attachment theory and coexisting with the Ostwald ripening theory,resulting in abundant pores formed by multiple layers of stacking in the products.With the optimal carbonization conditions,the rare earth precipitation yield solution reaches 99.32%.The obtained carbonization products are crystalline(LaCe)(CO_(3))_(3)·8H_(2)O,and the purity of the rare earth oxides is as high as 99.22 wt%.The specific surface area of the rare earth oxides reaches 94.7 m^(2)/g,and its adsorption efficiency for tetracycline hydrochloride in solution can reach 92.6%in a short time.The rare earth oxides are expected to be used as an adsorption material for wastewater treatment and other adsorption environments.
基金Supported by the Fourth Batch of Innovative Research Team Project at Zhaoqing University(TD202408)the 2024 Zhaoqing University Quality Engineering and Teaching Reform Project(zlgc2024002,zlgc2024092)+3 种基金the Ideological and Political Reform Demonstration Project of School-level Course at Zhaoqing College in 2024(Zhaoqing University[2024]83)the Zhaoqing University s"Double Hundred Project"Special General Project in 2025(SD202508)the 2025 Guangdong Province Graduate Education Innovation Plan Project(2025JGXM_177)the 2025 Guangdong Provincial Project for Young Innovative Talents in Ordinary Universities(2025KQNCX098).
文摘The absorption of air pollutants is an indicator for studying the value of forest land.It plays an important role in compiling resource balance sheets by studying the absorption of air pollutants by forest land.This paper focused on sulfur dioxide,an air pollutant.Through on-site air sample collection and laboratory testing,using the calculation method of the UFORE model issued by the US Forestry Administration,the annual absorption data of sulfur dioxide in different forest lands in Dapeng New Area were obtained.The results showed that there was not much difference in the absorption capacity of sulfur dioxide among the three types of forest lands in the new area:shrubland,broad-leaved forest,and artificial forest.The amount of sulfur dioxide absorbed per unit area ranged from 11.80 to 13.62 kg/(hm^(2)·a).However,coniferous forests had a lower absorption capacity for sulfur dioxide,with an absorption per unit area of 5.39 kg/(hm^(2)·a).
基金the National Key R&D Program of China(No.2022YFB4101900)National Natural Science Foundation of China(Nos.22278305,U21B2096)Natural Science Foundation of Tianjin City(No.23JCZDJC00040)。
文摘A strategy for copper-catalyzed and biphosphine ligand controlled boracarboxylation of 1,3-dienes and CO_(2) with 3,4-selectivity was developed.The Cu Cl coupled with DPPF(1,1-bis(diphenylphosphino)ferrocene)was assigned to be the best catalyst,with 84%yield and exclusive3,4-selectivity.The ligand effect on both catalytic activity and regioselectivity of boracarboxylation was disclosed,which is rarely reported in any copper catalyzed boracarboxylation.The borocupration process is revealed to be a vital step for the biphosphine participated boracarboxylation of 1,3-dienes with CO_(2).The minimal substrate distortion occurring in 3,4-borocupration favors the 3,4-regioselectivity of boracarboxylation.The“pocket”confinement and suitableβ_(n)(92°–106°)of bisphosphine ligands are demonstrated to be in favour of the interaction between LCu-Bpin complex(the catalytic precursor)and1,3-diene substrate to decrease their interaction energyΔE_(int)(ζ)in 3,4-borocupration,thus promoting the 3,4-boracarboxylation.
基金the Science and Technology Commission of Shanghai Municipality(No.18441904600)the Cross Research Fund for Translational Medicine of Shanghai Jiao Tong University(No.ZH2018ZDA14)。
文摘Endotracheal intubation has broad application prospects in the biomedical field.At present,visual intubation tools are mainly used to judge the catheter position.However,when patients suffer from pains in the neck,throat,and trachea and other diseases or other conditions,if the exposure of the glottic area is not ideal,there are difficult airways.For difficult airways,this visual intubation tool has great limitations.Studying the new guidance method of endotracheal intubation and providing a reference or solution for difficult airway intubation is a crucial problem in the biomedical clinical field.In this paper,an endotracheal intubation method is proposed based on end-tidal carbon dioxide(ETCO_(2))perception.The simulation model verifies the feasibility of this method for endotracheal intubation guidance.Then,four micro-cavity tubes are used as a gas collection tube,and a set of endotracheal tube guidance systems based on ETCO_(2) perception is designed and developed to collect and process the CO_(2) concentration information in the pharyngeal cavity.The experimental results show that this guidance system can be used for intubation guidance in the simulated pharyngeal cavity without vision.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDB0450202)。
文摘Strong Coulombic repulsion in small doubly charged molecular ions usually leads to fragmentation.Some of these ions,such as CO_(2)^(++),could survive and be detected if they are stable or metastable in energetics,but how to produce these observable doubly charged ions is a puzzling issue.Here we investigate CO_(2)^(++)production by electron-impact ionization with a supersonic molecular beam of CO_(2)under different nozzle pressures,using time-of-flight mass spectrometry measurements and ab initio calculations.The mass spectral profile of CO_(2)^(++)varies slightly with the nozzle pressure,implying different mechanisms of the ion production.The calculations indicate that the ground state of CO_(2)^(++)is 3Aʺwith a nonlinear conformation,while the linear conformer is in the first excited state 1Δ_(g).We further suggest that,besides CO_(2)^(++)(1Δ_(g))produced from CO_(2),CO_(2)^(++)(3Aʺ)could be produced by the dissociation of doubly charged dimer(C2O4^(++))in a repulsive triplet state.
基金supported by the Jiangxi Provincial Natural Science Foundation(No.20232BAB202036).
文摘Interlayer engineering of two-dimensional structural materials provides unique advantages for tuning the electromagnetic properties of metal oxides,injecting unlimited energy into the design of advanced two-dimensional metal oxide electromagnetic wave absorbers.In this study,Manganese dioxide intercalated with alkali metal ions was prepared by a simple molten salt method.The pre-intercalation of ions not only enhances the polarization loss at the heterogeneous interface between cations(point sites)and man-ganese dioxide(face sites)but also alters the energy band structure of manganese oxide and enhances its electrical conductivity,which in turn enhances the conductive loss of the manganese dioxide.Due to the synergistic effect of multiple polarizations and conductive losses,NaMO exhibits superb electromag-netic wave absorption properties and an effective absorption bandwidth of 5.36 GHz at thinner matched thicknesses.In addition,the RCS simulation result further verifies the excellent electromagnetic wave ab-sorption capability of NaMO.Under the positive incidence of electromagnetic waves,the electromagnetic wave reflection intensity of the metal plate coated with NaMO is effectively reduced.Finally,this work establishes a new way to modulate the electromagnetic properties.
