Blood glucose-lowering activity of protocatechuic acid is mediated by inhibiting a-glucosidase

α-Glucosidase inhibitors are effective in controlling postprandial hyperglycemia,which play crucial roles in the management of type 2 diabetes.Protocatechuic acid(PCA)is one of phenolic acids existing not only in various plant foods but also as a major microbial metabolite of dietary anthocyanins in the large colon.The present study investigated the inhibitory mechanism of PCA on a-glucosidase in vitro and examined its effect on postprandial blood glucose levels in vivo.Results from in vitro experiments demonstrated that PCA was a mix-type inhibitor of a-glucosidase.Driven by hydrogen bonds and van der Waals interactions,PCA reversibly bound withα-glucosidase to form a stable a-glucosidase-PCA complex in a spontaneous manner.The computational simulation found that PCA could insert into the active cavity of a-glucosidase and establish hydrogen bonds with catalytic amino acid residues.PCA binding aroused the steric hindrance for substrates to enter active sites and caused the structural changes of interacted catalytic amino acid residues.PCA also exhibited postprandial hypoglycemic capacity in diabetic mice.This study may provide the theoretical basis for the application of PCA as an active ingredient of functional foods in dietary management of diabetes.

Antioxidant,antimicrobial,and α-glucosidase inhibitory activities of saponin extracts from walnut(Juglans regia L.) leaves

Objective:To investigate the relationship between triterpenoid saponin content and antioxidant,antimicrobial,and α-glucosidase inhibitory activities of 70%ethanolic,butanolic,aqueous,supernate and precipitate extracts of Juglans regia leaves.Methods:Triterpenoid saponins of different Juglans regia leaf extracts were measured by the vanillin method.Antioxidant activity was evaluated against DPPH and ABTS free radicals.We also assessed α-glucosidase inhibitory and antimicrobial activities of the leaf extracts.Pearson’s correlation coefficient was evaluated to determine the correlation between the saponin content and biological activities.Results:The butanolic extract was most effective against DPPH with an IC50of 6.63μg/mL,while the aqueous extract showed the highest scavenging activity against ABTS free radical with an IC50of 42.27μg/mL.Pearson’s correlation analysis indicated a strong negative correlation (r=-0.956) between DPPH radical scavenging activity (IC50) and the saponin content in the samples examined.In addition,the aqueous extract showed the best α-glucosidase inhibitory activity compared with other extracts.All the extracts had fair antibacterial activity against Bacillus subtilis,Escherichia coli,and Klebsiella pneumoniae except for the aqueous extract.Conclusions:Juglans regia extracts show potent antioxidant,antimicrobial,and α-glucosidase inhibitory activities.There is a correlation between saponin levels in Juglans regia leaf extracts and the studied activities.However,additional research is required to establish these relationships by identifying the specific saponin molecules responsible for these activities and elucidating their mechanisms of action.

Enabling heterogeneous catalysis to achieve carbon neutrality: Directional catalytic conversion of CO_(2) into carboxylic acids

The increase in anthropogenic carbon dioxide(CO_(2))emissions has exacerbated the deterioration of the global environment,which should be controlled to achieve carbon neutrality.Central to the core goal of achieving carbon neutrality is the utilization of CO_(2) under economic and sustainable conditions.Recently,the strong need for carbon neutrality has led to a proliferation of studies on the direct conversion of CO_(2) into carboxylic acids,which can effectively alleviate CO_(2) emissions and create high-value chemicals.The purpose of this review is to present the application prospects of carboxylic acids and the basic principles of CO_(2) conversion into carboxylic acids through photo-,electric-,and thermal catalysis.Special attention is focused on the regulation strategy of the activity of abundant catalysts at the molecular level,inspiring the preparation of high-performance catalysts.In addition,theoretical calculations,advanced technologies,and numerous typical examples are introduced to elaborate on the corresponding process and influencing factors of catalytic activity.Finally,challenges and prospects are provided for the future development of this field.It is hoped that this review will contribute to a deeper understanding of the conversion of CO_(2) into carboxylic acids and inspire more innovative breakthroughs.

Structural characterizations andα-glucosidase inhibitory activities of four Lepidium meyenii polysaccharides with different molecular weights

Four polysaccharides(MCPa,MCPb,MCPc,MCPd)were obtained from Lepidium meyenii Walp.Their structures were characterized by chemical and instrumental methods including total sugar,uronic acid and protein content determi-nation,UV,IR and NMR spectroscopy,as well as monosaccharide composition determination and methylation analy-ses.Four polysaccharides were a group of glucans with different molecular weights ranging from 3.12 to 14.4 kDa,and shared a similar backbone chain consisting of(1→4)-glucose linkages with branches attached to C-3 and C-6.Furthermore,bioactivity assay showed that MCPs had concentration-dependent inhibitory activity onα-glucosidase.MCPb(Mw=10.1 kDa)and MCPc(Mw=5.62 kDa)with moderate molecular weights exhibited higher inhibitory activ-ity compared with MCPa and MCPd.

Ethanol extract of Annona muricata Linn fruit perform antidiabetic effect on type 2 diabetic mice through α-glucosidase inhibition

Objective:To explore the anti-diabetic effects and its underlying mechanism of Annona muricata Linn fruit ethanol extract(AME).Methods:Streptozotocin-induced type 2 diabetic(T2DM)mouse model was constructed.Those diabetic mice were randomly grouped and given 50 mg/kg acarbose or AME(200 mg/kg,100 mg/kg or 50 mg/kg)for four weeks.The body weight,postprandial blood glucose and glycosylated hemoglobin levels were measured during the administration.After the administration,a glucose tolerance test was performed,and the levels of triglycerides,cholesterol and low-density lipoproteins in mice were detected by biochemical test kits.The inhibitory activity of AME onα-glucosidase in vivo and in vitro was determined by enzyme inhibition tests.Results:AME significantly reduced weight gain,postprandial blood glucose,glycosylated hemoglobin and low-density lipoprotein levels in T2DM mice;enhanced glucose tolerance and pancreaticβ-cell function of T2DM mice;inhibitedα-glucosidase activity in mouse intestine in an noncompetitive manner.Conclusion:AME may noncompetitive inhibitα-glucosidase activity and reduce postprandial glucose intake to achieve a therapeutic and regulatory effect on type 2 diabetes.

The research progress of an E//B neutral particle analyzer

An E//B neutral particle analyzer(NPA)has been designed and is under development at Sichuan University and Southwestern Institute of Physics.The main purpose of the E//B NPA is to measure the distribution function of fast ions in the HL-2A/3 tokamak.The E//B NPA contains three main units,i.e.the stripping unit,the analyzing unit and the detection unit.A gas stripping chamber was adopted as the stripping unit.The results of the simulations and beam tests for the stripping chamber are presented.Parallel electric and magnetic fields provided by a NdFeB permanent magnet and two parallel electric plates were designed and constructed for the analyzing unit.The calibration of the magnetic and electric fields was performed using a 50 kV electron cyclotron resonance ion source(ECRIS)platform.The detection unit consists of 32lutetium-yttrium oxyorthosilicate(LYSO)detector modules arranged in two rows.The response functions ofα,hydrogen ions(H^(+),H_(2)^(+)and H_(3)^(+))andγfor a detector module were measured with^(241)Am,^(137)Cs and^(152)Eu sources together with the 50 kV ECRIS platform.The overall results indicate that the designed E//B NPA device is capable of measuring the intensity of neutral hydrogen and deuteron atoms with energy higher than 20 keV.

Connotation,pathway and significance of carbon neutrality“super energy system”:A case study of the Ordos Basin,NW China

Super oil and gas basins provide the energy foundation for social progress and human development.In the context of climate change and carbon peak and carbon neutrality goals,constructing an integrated energy and carbon neutrality system that balances energy production and carbon reduction becomes crucial for the transformation of such basins.Under the framework of a green and intelligent energy system primarily based on“four news”,new energy,new electricity,new energy storage,and new intelligence,integrating a“super energy system”composed of a huge amount of underground resources of coal,oil,gas and heat highly overlapping with abundant wind and solar energy resources above ground,and a regional intelligent energy consumption system with coordinated development and utilization of fossil energy and new energy,with a carbon neutrality system centered around carbon cycling is essential.This paper aims to select the traditional oil and gas basins as“super energy basins”with the conditions to build world-class energy production and demonstration bases for carbon neutrality.The Ordos Basin has unique regional advantages,including abundant fossil fuel and new energy resources,as well as matching CO_(2)sources and sinks,position it as a carbon neutrality“super energy basin”which explores the path of transformation of traditional oil and gas basins.Under the integrated development concept and mode of“coal+oil+gas+new energy+carbon capture,utilization and storage(CCUS)/carbon capture and storage(CCS)”,the carbon neutrality in super energy basin is basically achieved,which enhance energy supply and contribute to the carbon peak and carbon neutrality goals,establish a modern energy industry and promote regional green and sustainable development.The pioneering construction of the world-class carbon neutrality“super energy system”demonstration basin in China represented by the Ordos Basin will reshape the new concept and new mode of exploration and development of super energy basins,which is of great significance to the global energy revolution under carbon neutrality.

Carbon neutrality:China's energy transition over the past decade

China's energy transition is based on accelerating the construction of a clean,low-carbon,safe,and efficient new energy system(Fig.1),providing strong energy security for economic and social development;focusing on ecological civilization construction,and accelerating the formation of a new energy consumption model that is efficient,green,inclusive,and beneficial,while promoting carbon reduction,pollution reduction,expansion of green spaces,and economic growth.

Amorphous core-shell NiMoP@CuNWs rod-like structure with hydrophilicity feature for efficient hydrogen production in neutral media

Using interface engineering,a highly efficient catalyst with a shell@core structure was successfully synthesized by growing an amorphous material composed of Ni,Mo,and P on Cu nanowires(Ni-MoP@CuNWs).This catalyst only requires an overpotential of 35 mV to reach a current density of 10 mA cm^(-2).The exceptional hydrogen evolution reaction(HER)activity is attributed to the unique amorphous rod-like nature of NiMoP@CuNWs,which possesses a special hydrophilic feature,en-hances mass transfer,promotes effective contact between the electrode and electrolyte solution,and exposes more active sites during the catalytic process.Density functional theory revealed that the introduction of Mo weakens the binding strength of the Ni site on the catalyst surface with the H atom and promotes the desorption process of the H_(2) product significantly.Owing to its facile syn-thesis,low cost,and high catalytic performance,this electrocatalyst is a promising option for com-mercial applications as a water electrolysis catalyst.

Ultralow charge-discharge voltage gap of 0.05 V in sunlight-responsive neutral aqueous Zn-air battery

Rechargeable neutral aqueous zinc-air batteries(ZABs)are a promising type of energy storage device with longer operating life and less corrosiveness compared with conventional alkaline ZABs.However,the neutral ZABs normally possess poor oxygen evolution reactions(OERs)and oxygen reduction reactions performance,resulting in a large charge–discharge voltage gap and low round-trip efficiency.Herein,we demonstrate a sunlight-assisted strategy for achieving an ultralow voltage gap of 0.05 V in neutral ZABs by using the FeOOH-decorated BiVO4(Fe-BiVO4)as an oxygen catalyst.Under sunlight,the electrons move from the valence band(VB)of Fe-BiVO_(4) to the conduction band producing holes in VB to promote the OER process and hence reduce the overpotential.Meanwhile,the photopotential generated by the Fe-BiVO_(4) compensates a part of the charging potential of neutral ZABs.Accordingly,the energy loss of the battery could be compensated via solar energy,leading to a record-low gap of 0.05 V between the charge and discharge voltage with a high round-trip efficiency of 94%.This work offers a simple but efficient pathway for solar-energy utilization in storage devices,further guiding the design of high energy efficiency of neutral aqueous ZABs.

A Unifi ed View of Carbon Neutrality:Solar-Driven Selective Upcycling of Waste Plastics

With the rapid development of plastic production and consumption globally,the amount of post-consumer plastic waste has reached levels that have posed environmental threats.Considering the substantial CO_(2)emissions throughout the plastic lifecycle from material production to its disposal,photocatalysis is considered a promising strategy for eff ective plastic recycling and upcycling.It can upgrade plastics into value-added products under mild conditions using solar energy,realizing zero carbon emissions.In this paper,we explain the basics of photocatalytic plastic reformation and underscores plastic feedstock reformation pathways into high-value-added products,including both degradation into CO_(2)followed by reformation and direct reformation into high-value-added products.Finally,the current applications of transforming plastic waste into fuels,chemicals,and carbon materials and the outlook on upcycling plastic waste by photocatalysis are presented,facilitating the realization of carbon neutrality and zero plastic waste.

Recent advances in nickel-based catalysts in eCO_(2)RR for carbon neutrality

The excessive use of nonrenewable energy has brought about serious greenhouse effect.Converting CO_(2) into high-value-added chemicals is undoubtedly the best choice to solve energy problems.Due to the excellent cost-effectiveness and dramatic catalytic performance,nickel-based catalysts have been considered as the most promising candidates for the electrocatalytic CO_(2) reduction reaction(eCO_(2)RR).In this work,the electrocatalytic reduction mechanism of CO_(2) over Ni-based materials is reviewed.The strategies to improve the eCO_(2)RR performance are emphasized.Moreover,the research on Ni-based materials for syngas generation is briefly summarized.Finally,the prospects of nickel-based materials in the eCO_(2)RR are provided with the hope of improving transition-metal-based electrocatalysts for eCO_(2)RR in the future.

Striking Stabilization Effect of Spinel Cobalt Oxide Oxygen Evolution Electrocatalysts in Neutral pH by Dual-Sites Iron Incorporation

Developing stable and efficient nonprecious-metal-based oxygen evolution catalysts in the neutral electrolyte is a challenging but essential goal for various electrochemical systems.Particularly,cobalt-based spinels have drawn a considerable amount of attention but most of them operate in alkali solutions.However,the frequently studied Co-Fe spinel system never exhibits appreciable stability in nonbasic conditions,not to mention attract further investigation on its key structural motif and transition states for activity loss.Herein,we report exceptional stable Co-Fe spinel oxygen evolution catalysts(~30%Fe is optimal)in a neutral electrolyte,owing to its unique metal ion arrangements in the crystal lattice.The introduced iron content enters both the octahedral and tetrahedral sites of the spinel as Fe^(2+)and Fe^(3+)(with Co ions having mixed distribution as well).Combining density functional theory calculations,we find that the introduction of Fe to Co_(3)O_(4)lowers the covalency of metal-oxygen bonds and can help suppress the oxidation of Co^(2+/3+)and 0^(2-).It implies that the Co-Fe spinel will have minor surface reconstruction and less lattice oxygen loss during the oxygen evolution reaction process in comparison with Co_(3)O_(4)and hence show much better stability.These findings suggest that there is still much chance for the spinel structures,especially using reasonable sublattices engineering via multimetal doping to develop advanced oxygen evolution catalysts.

A NOTE ON THE GENERAL STABILIZATION OF DISCRETE FEEDBACK CONTROL FOR NON-AUTONOMOUS HYBRID NEUTRAL STOCHASTIC SYSTEMS WITH A DELAY

Discrete feedback control was designed to stabilize an unstable hybrid neutral stochastic differential delay system(HNSDDS) under a highly nonlinear constraint in the H_∞ and exponential forms.Nevertheless,the existing work just adapted to autonomous cases,and the obtained results were mainly on exponential stabilization.In comparison with autonomous cases,non-autonomous systems are of great interest and represent an important challenge.Accordingly,discrete feedback control has here been adjusted with a time factor to stabilize an unstable non-autonomous HNSDDS,in which new Lyapunov-Krasovskii functionals and some novel technologies are adopted.It should be noted,in particular,that the stabilization can be achieved not only in the routine H_∞ and exponential forms,but also the polynomial form and even a general form.

Emission-side drivers affecting carbon neutrality based on vegetation carbon sequestration:Evidence from China

To address climate change,the world needs deep decarbonization to achieve carbon neutrality(CN),which implies net-zero human-caused CO_(2) emissions in the atmosphere.This study used emission-side drivers,including socioeconomic and net primary productivity(NPP)-based factors,to determine the changes in CN based on vegetation carbon sequestration in the case of China during 2001-2015.Spatial exploratory analysis as well as the combined use of production-theoretical decomposition analysis(PDA)and an econometric model were also utilized.We showed that CN was significantly spatially correlated over the study period;Yunnan,Heilongjiang,and Jilin presented positive spatial autocorrelations,whereas Guizhou showed a negative spatial autocorrelation.More than half of CN declined over the period during which potential energy intensity(PEIE)and energy usage technological change were the largest negative and positive drivers for increasing CN.PEIE played a significantly negative role in increasing CN.We advise policymakers to focus more on emission-side drivers(e.g.,energy intensity)in addition to strengthening NPP management to achieve CN.

Development,challenges and strategies of natural gas industry under carbon neutral target in China

In the mid-21st century,natural gas will enter its golden age,and the era of natural gas is arriving.This paper reviews the development stages of global natural gas industry and the enlightenment of American shale gas revolution,summarizes the development history and achievements of the natural gas industry in China,analyzes the status and challenges of natural gas in the green and low-carbon energy transition,and puts forward the natural gas industry development strategies under carbon neutral target in China.The natural gas industry in China has experienced three periods:start,growth,and leap forward.At present,China has become the fourth largest natural gas producer and third largest natural gas consumer in the world,and has made great achievements in natural gas exploration and development theory and technology,providing important support for the growth of production and reserves.China has set its goal of carbon neutrality to promote green and sustainable development,which brings opportunities and challenges for natural gas industry.Natural gas has significant low-carbon advantages,and gas-electric peak shaving boosts new energy development;the difficulty and cost of development are more prominent.For the national energy security and harmonious development between economy and ecology under the carbon neutral goal,based on the principle of"comprehensive planning,technological innovation,multi-energy complementarity,diversified integration,flexibility and efficiency,optimization and upgrading",the construction of the production-supplystorage-marketing system has to be improved so as to boost the development of the natural gas industry.First,it is necessary to strengthen efforts in the exploration and development of natural gas,making projects and arrangement in key exploration and development areas,meanwhile,it is urgent to make breakthroughs in key science theories and technologies,so as to increase reserve and production.Second,it should promote green and innovative development of the natural gas by developing new techniques,expanding new fields and integrating with new energy.Third,there is a demand to realize transformation and upgrading of the supply and demand structure of natural gas by strengthening the layout of pipeline gas,liquefied natural gas and the construction of underground gas storage,establishing reserve system for improving abilities of emergency response and adjustment,raising the proportion of natural gas in the primary energy consumption and contributing to the transformation of energy consumption structure,realizing low-carbon resources utilization and clean energy consumption.

Research on uninterruptable power supply technology for auxiliary winding of electric locomotive while passing the neutral section

Purpose–Auxiliary power system is an indispensable part of the train;the auxiliary systems of both electric locomotives and EMUs mainly are powered by one of the two ways,which are either from auxiliary windings of traction transformers or from DC-link voltage of traction converters.Powered by DC-link voltage of traction converters,the auxiliary systems were maintained of uninterruptable power supply with energy from electric braking.Meanwhile,powered by traction transformers,the auxiliary systems were always out of power while passing the neutral section of power supply grid and control system is powered by battery at this time.Design/methodology/approach–Uninterrupted power supply of auxiliary power system powered by auxiliary winding of traction transformer was studied.Failure reasons why previous solutions cannot be realized are analyzed.An uninterruptable power supply scheme for the auxiliary systems powered by auxiliary windings of traction transformers is proposed in this paper.The validity of the proposed scheme is verified by simulation and experimental results and on-site operation of an upgraded HXD3C type locomotive.This scheme is attractive for upgrading practical locomotives with the auxiliary systems powered by auxiliary windings of traction transformers.Findings–This scheme regenerates braking power supplied to auxiliary windings of traction transformers while a locomotive runs in the neutral section of the power supply grid.Control objectives of uninterrupted power supply technology are proposed,which are no overvoltage,no overcurrent and uninterrupted power supply.Originality/value–The control strategies of the scheme ensure both overvoltage free and inrush current free when a locomotive enters or leaves the neutral section.Furthermore,this scheme is cost low by employing updated control strategy of software and add both the two current sensors and two connection wires of hardware.

Emerging CCER Scheme Promotes Carbon Neutrality

THE China Certified Emission Reduction(CCER)scheme is a vital channel that is helping China and its enterprises achieve carbon neutrality.At the same time,it is also promoting the development of the carbon market and low-cost emission reduction.Since an interim administrative document on voluntary greenhouse gas emission reduction trading was issued in 2012,a relatively complete operating and management system has been established and a constant flow of trading has been carried out.

Evolution and Characteristics of "Carbon Neutrality Movies"

"Carbon neutrality movies"are movies that focus on carbon neutrality as the object of expression and dissemination.Using carbon neutrality as an element,it influences the development of the plot,reflects environmental changes,and focuses on climate change caused by carbon emissions.At the same time,it focuses on offsetting carbon emissions through carbon neutrality behavior,showcasing the impact of carbon neutrality.From the perspective of ecological movies,the evolution of carbon neutrality movies at three stages can be explored.The first stage is high-carbon movies that reflect the high conflict between humans and the natural environment.The second stage is low-carbon movies,reflecting humanity's pursuit of a harmonious coexistence between humans and nature,thus adopting green and low-carbon behaviors.The third stage is carbon neutrality movies,which awaken or guide the public to pay attention to carbon emissions,promote low-carbon living,guide life practice in a carbon neutrality way,and create a better life.There are three characteristics of"carbon neutrality movies",including scientific reflection on global warming,advocating energy conservation and emission reduction in daily life,and promoting clean energy in policies.

CO_(2) electrolysis to formic acid for carbon neutralization

To avoid carbonate precipitation for CO_(2) electrolysis,developing CO_(2) conversion in an acid electrolyte is viewed as an ultimately challenging technology.In Nature,Xia et al.recently explored a proton-exchange membrane system for reducing CO_(2) to formic acid with a Pb±Pb SO_(4) composite catalyst derived from waste lead-acid batteries based on the lattice carbon activation mechanism.Up to 93%Faradaic efficiency was realized when formic acid was produced by this technology.