CRISPR-Cas12a-Empowered Electrochemical Biosensor for Rapid and Ultrasensitive Detection of SARS-CoV-2 Delta Variant

Coronavirus disease 2019(COVID-19)is a highly contagious disease caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).The gold standard method for the diagnosis of SARS-CoV-2 depends on quantitative reverse transcription-polymerase chain reaction till now,which is time-consuming and requires expensive instrumentation,and the confirmation of variants relies on further sequencing techniques.Herein,we first proposed a robust technique-methodology of electrochemical CRISPR sensing with the advantages of rapid,highly sensitivity and specificity for the detection of SARS-CoV-2 variant.To enhance the sensing capability,gold electrodes are uniformly decorated with electro-deposited gold nanoparticles.Using DNA template identical to SARS-CoV-2 Delta spike gene sequence as model,our biosensor exhibits excellent analytical detection limit(50 fM)and high linearity(R2=0.987)over six orders of magnitude dynamic range from 100 fM to 10 nM without any nucleic-acid-amplification assays.The detection can be completed within 1 h with high stability and specificity which benefits from the CRISPR-Cas system.Furthermore,based on the wireless micro-electrochemical platform,the proposed biosensor reveals promising application ability in point-of-care testing.

New Decision-Making Technique Based on Hurwicz Criteria for Fuzzy Ranking

Efficient decision-making remains an open challenge in the research community,and many researchers are working to improve accuracy through the use of various computational techniques.In this case,the fuzzification and defuzzification processes can be very useful.Defuzzification is an effective process to get a single number from the output of a fuzzy set.Considering defuzzification as a center point of this research paper,to analyze and understand the effect of different types of vehicles according to their performance.In this paper,the multi-criteria decision-making(MCDM)process under uncertainty and defuzzification is discussed by using the center of the area(COA)or centroidmethod.Further,to find the best solution,Hurwicz criteria are used on the defuzzified data.Anewdecision-making technique is proposed using Hurwicz criteria for triangular and trapezoidal fuzzy numbers.The proposed technique considers all types of decision makers’perspectives such as optimistic,neutral,and pessimistic which is crucial in solving decisionmaking problems.A simple case study is used to demonstrate and discuss the Centroid Method and Hurwicz Criteria for measuring risk attitudes among decision-makers.The significance of the proposed defuzzification method is demonstrated by comparing it to previous defuzzification procedures with its application.

A Hybrid Deep Learning Approach to Classify the Plant Leaf Species

Many plant species have a startling degree of morphological similarity,making it difficult to split and categorize them reliably.Unknown plant species can be challenging to classify and segment using deep learning.While using deep learning architectures has helped improve classification accuracy,the resulting models often need to be more flexible and require a large dataset to train.For the sake of taxonomy,this research proposes a hybrid method for categorizing guava,potato,and java plumleaves.Two new approaches are used to formthe hybridmodel suggested here.The guava,potato,and java plum plant species have been successfully segmented using the first model built on the MobileNetV2-UNET architecture.As a second model,we use a Plant Species Detection Stacking Ensemble Deep Learning Model(PSD-SE-DLM)to identify potatoes,java plums,and guava.The proposed models were trained using data collected in Punjab,Pakistan,consisting of images of healthy and sick leaves from guava,java plum,and potatoes.These datasets are known as PLSD and PLSSD.Accuracy levels of 99.84%and 96.38%were achieved for the suggested PSD-SE-DLM and MobileNetV2-UNET models,respectively.

Interleukin-1 receptor antagonist:From synthesis to therapeutic applications

The cytokine channel’s mechanism for self-regulation involves the application of antagonistic cytokines that are synthesized to connect to the receptors and release soluble cytokine receptors.The very first receptor antagonist of cytokine that was naturally present was interleukin-1 receptor antagonist(IL-1Ra).The IL-1Ra protein forms are disinfected from supernatants of cultured monocytes on stacked IgG.The family of IL-1 consists of IL-1α,IL-1βand IL-1Ra.Human monocytes regulate the production of IL-Ra.IL-Ra takes part in normal physiological functions by using specific antibodies,and acts as an anti-inflammatory agent.IL-Ra is synthesized in the tissues during the period of active disease and can be systematically measured and/or estimated.Maintenance of the levels of IL-Ra and IL-1 is the main factor for host resistance in patients during diseased conditions,as IL-Ra acts as an inherent regulator of various inflammatory responses.In this article,we focuse on how IL-Ra is synthesized and performs its functions once the inflammatory responses are activated.

Biochemical association between the prevalence of genetic polymorphism and myocardial infarction

Genetic polymorphism has a vital role in the pathogenesis and development of myocardial infarction(MI).Single nucleotide polymorphism at any one of the amino acid sequences can result in a diseased state.A single gene can exhibit genetic polymorphism at more than one position giving rise to different variants.Genetic polymorphism of angiotensinogen(AGT)M235T,AGT T174M,and angiotensin-1-converting enzyme(ACE)I/D,endothelial nitric oxide synthase(eNOS),and methylenetetrahydrofolate reductase(MTHFR)can be a risk factor for MI.However,it is important to study the prevalence of genetic polymorphisms of these genes among different populations.MI is influenced by genetic polymorphism of various genes,including AGT,ACE,eNOS,MTHFR,etc.However,the association of genetic polymorphism of these genes varies among different populations,but different ethnic groups could show contradictory results.These genes have shown a positive association with risks of MI in some populations,whereas the results have not been consistent with every ethnic group.In this article,we have summarized the genetic variations in the aforementioned genes and their association with MI.

纳米流体在平板上的湍流边界层和流体流动分析

对分别浸入3种纳米流体(ZnO-水,SiO_(2)-水,TiO_(2)-水)的平板近壁面流动的湍流边界层的对数规律进行数值分析。采用CFD程序对边界层和流体动力流动进行数值模拟。使用已发表的测量点对数值模型进行验证,结果表明一致性较好。对流速0.04 m/s,0.4 m/s,4 m/s以及纳米颗粒浓度0.1%和5%的情况进行模拟。研究了纳米颗粒浓度对速度、温度分布、壁面剪切应力和湍流强度的影响。结果表明:沿势流层的黏性亚层、缓冲层和对数律层可以基于具有单壁距离区域的弯曲质量进行分析。可见,与其他区域相比,黏性亚层面积最大。另一方面,温度变化与热边界层厚度有关的区域在流速减小时也减小,热边界层离前缘越来越深,而纳米颗粒体积分数的增加对壁面剪切应力的影响较小。在所有情况下,边界层的厚度都随着流速的增加而减小,而纳米颗粒浓度的增加会使边界层的厚度增加。更准确地说,对数层在Y^(+)=50和Y^(+)=95之间最小。在所研究的纳米流体中,φ=5%时的边界层温度高于φ=0.1%时的边界层温度。而Y^(+)=1时,结果正好相反,φ=0.1%时的温度比φ=5%的更高。当流速分别为v=4,0.4,0.04 m/s时,湍流强度峰值分别出现在Y^(+)=100,Y^(+)=10和Y^(+)=8时。

Linear and nonlinear optical analysis on semiorganic-proline cadmium chloride single crystal

In the current investigation,L-proline cadmium chloride monohydrate（LPCC） single crystal is grown by a slow solvent evaporation technique to identify its credibility for nonlinear optical device applications.The constituent elements of LPCC crystal are determined by the energy dispersive spectroscopic（EDS） technique.The single crystal x-ray diffraction technique is used to determine the structural dimensions of LPCC crystal.The UV-visible studies are carried out within a wavelength range of 200 nm–1100 nm to determine the optical transmittance of LPCC crystal.The linear optical parameters of LPCC crystal are evaluated using the transmittance data to discuss its importance for distinct optical devices.The Nd：YAG laser assisted Kurtz–Perry test is carried out to determine the enhancement in second harmonic generation efficiency of LPCC crystal with reference to KDP crystal.The Z-scan technique is employed to assess the third order nonlinear optical（TONLO） properties of LPCC crystal at 632.8 nm.The Z-scan data are utilized to evaluate the TONLO refraction,absorption and susceptibility of LPCC crystal.The color oriented luminescence behavior of LPCC crystal is investigated within a spectral range of 350 nm–700 nm.The dependence of dielectric constant and dielectric loss on temperature and frequency is evaluated through the dielectric measurement studies.

Pterostilbene induces cell apoptosis and inhibits lipogenesis in SKOV3 ovarian cancer cells by activation of AMPK-induced inhibition of Akt/mTOR signaling cascade

This study investigates if the anti-tumor effect of Pterostilbene in the SKOV3 ovarian cancer(OC)cell line involves inhibition of cell metabolism and tested in this effect involves modulating AMPK and Akt-induced regulation of mTORC1.Initially,SKOV3 cells were cultured in the humidified conditions in DMEM media for 24 h with or without increasing concentration of Pterostilbene.Then,the cells were incubated with Pterostilbene(IC_(50)=50μM)under similar conditions with or without pre-incubation with Dorsomorphin,an AMPK inhibitor.In a dose-dependent manner,Pterostilbene inhibited SKOV3 cell survival and increased their lysate levels of lactate dehydrogenase(LDH)and single-stranded DNA(ssDNA).When SKOV3 cells were treated with 50μM Pterostilbene,Pterostilbene significantly suppressed cell migration and invasion,reduced lysate levels of lactic acid and the optical density of Oil Red O staining,and increased lysate glucose levels.It also increased levels of malondialdehyde(MDA),reactive oxygen species(ROS),and induced intrinsic cell apoptosis by upregulating protein levels of Bax and cleaved caspase-3 and reducing protein levels of Bcl-2.Besides,Pterostilbene reduced mRNA levels of sterol regulatory element-binding protein 1(SREBP-1),fatty acid synthase(FAS),acetyl CoA carboxylase-1(ACC-1),and AMP-activated protein kinase(AMPK).Furthermore,Pterostilbene increased the protein levels of p-AMPK,p-p53,p-raptor,p-TSC-2,but significantly decreased protein levels of p-Akt,p-TSC-2,p-mTOR,p-S6K1,and p-4E-BP.Treatment with Dorsomorphin(CC)abolished all the anti-tumorigenesis effects afforded by Pterostilbene and prevented Pterostilbene-induced phosphorylation of Akt,p53,and mTOR.In conclusion,the tumorsuppressive effect of Pterostilbene in SKOV3 cells involves the induction of ROS and inhibition of dysregulation cell metabolism mainly due to AMPK-induced Akt-dependent or independent suppression of mTOR.

Complex Permittivity and Permeability Studies Viewing Antenna Applications of NBR-Based Composites Comprising Conductive Fillers

The work presents studies on the complex permittivity and permeability of composites based on acrylonitrile butadiene rubber containing combinations of conductive fillers which include carbon black and nickel powder. The properties of those composites, containing each of the fillers at the same amount were compared. The permittivity and permeability values of the composites are influenced remarkably by their morphology and structure as well as by the morphological and structural specifics of both fillers. As electron scanning microscopy studies confirm, those parameters are predetermined by the nature of the composites studied—particle size, particles arrangement in the matrix and their tendency to clustering. Last but not least matrix-filler interface phenomena also impact the characteristics in question. The possibilities for applications of the composites in antennae have been studied, in particular, as substrates and insulating layers in flexible antennae for body centric communications (BCCs). The research results allow the conclusion that these materials can find such applications indeed. Composites of higher conductivity can be used where surface waves are generated to provide on-body communications, while composites of lower conductivity may be used for antennae that will be on the body of a person and will transmit to and receive from other antennas that are not on the body of the same person (off-body communications). It is clear that one can engineer the properties of antennae substrates at microwave frequencies by adjusting the filler content and the type of filler and thus control and tailor the antenna performance specific for a particular application.

Interlayer sensitized van der Waals heterojunction photodetector with enhanced performance

Although photodetection based on two-dimensional(2D)van der Waals(vdWs)P-N heterojunction has attracted extensive attention recently,their low responsivity(R)due to the lack of carrier gain mechanism in reverse bias or zero bias operation hinders their applications in advanced photodetection area.Here,a black phosphorus/rhodamine 6G/molybdenum disulfide(BP/R6G/MoS_(2))photodiode with high responsivity at reverse bias or zero bias has been achieved by using interfacial charge transfer of R6G molecules assembled between heterojunction layers.The formed vdWs interface achieves high performance photoresponse by efficiently separating the additional photogenerated electrons and holes generated by R6G molecules.The devices sensitized by the dye molecule R6G exhibit enhanced photodetection performance without sacrificing the photoresponse speed.Among them,the R increased by 14.8-20.4 times,and the specific detectivity(D^(*))increased by 24.9-34.4 times.The strategy based on interlayer assembly of dye molecules proposed here may pave a new way for realizing high-performance photodetection based on 2D vdWs heterojunctions with high responsivity and fast response speed.

Few-layer Ti_(3)CN MXene for ultrafast photonics applications in visible band

Ti_(3)CN,as a typical hetero-MXene,has attracted tremendous attention for its unique properties.However,its ultrafast photonics applications are still rare.Here,the few-layer Ti_(3)CN MXene was successfully prepared by selective etching and molecular delamination technique.The nonlinear optical response of few-layer Ti_(3)CN MXene at 640 nm was studied using the open-aperture Z-scan technique.The asprepared Ti_(3)CN MXene sample exhibited excellent nonlinear saturable absorption characteristics,resulting in the nonlinear absorption coefficient b of
4.05×10^(-2)cm/GW,which was one order of magnitude larger than that of black phosphorus(BP)and molybdenum disulfide(MoS_(2)).For the optical modulation applications of few-layer Ti_(3)CN MXene,passively Q-switched(PQS)solid-state visible lasers based on Ti_(3)CN saturable absorber(SA)at 522 nm,607 nm,639 nm,and 721 nm were successfully realized.Furthermore,a Ti_(3)CN-based stable passively mode-locked Pr:YLF red laser was also successfully achieved with a pulse duration of 30 ps,and the corresponding repetition rate was 73.1 MHz.The optical modulation device based on few-layer Ti_(3)CN MXene shows good performance.Our work demonstrates that the tremendous prospects of the few-layer Ti_(3)CN MXene as a visible optical modulation device in ultrafast photonics applications.

Fully depleted vdW heterojunction based high performance photovoltaic photodetector

Van der Waals(vdW)heterojunctions,with their unique electronic and optoelectronic properties,have become promising candidates for photodetector applications.Amplifying the contribution of the depletion region in vdW heterojunction,which would enhance both of the collection efficiency and speed of the photogenerated carriers,presents an effective strategy for achieving high performance vdW heterojunction photodetectors.Herein,a fully depleted vdW heterojunction photodetector is built on two-dimensional(2D)semiconductor materials(GaTe and InSe)layered on a pattered bottom electrode in vertical structure,in which the generation and motion of carriers are exclusively achieved in the depletion region.Attributed to the intrinsic built-in electric field,the elimination of series resistance and the depletion region confinement of carriers,the as-fabricated photodetector exhibits prominent photovoltaic properties with a high open-circuit voltage of 0.465 V,as well as photoresponse characteristics with outstanding responsivity,detectivity and photoresponse speed of 63.7 A/W,3.88×10^(13)Jones,and 32.7 ms respectively.The overall performance of this fully depleted GaTe/InSe vdW heterojunctions photodetectors are ranking high among the top level of 2D materials based photodetectors.It indicates the device architecture can provide new opportunities for the fabrication of high-performance photodetectors.

A new fractional order 6D chaotic model:Study of model dynamics,system structure graph,electronic circuit realization and fractional control

A new fractional 6D chaotic model is constructed in this paper.The new fractional 6D chaotic model has six positive parameters plus the fractional order with eight nonlinear terms.The complicated chaotic dy-namics of the new fractional 6D model is presented and analyzed.The basic properties of this model are studied and its chaotic attractors,dissipative feature,symmetry,equilibrium points,Lyapunov Exponents are investigated.The new dynamics of the 6D fractional model is numerically simulated using Matlab software.In addition,utilizing the graph theory tools certain structural characteristics are calculated.An electrical circuit is built to implement the new 5.4 fractional order 6D model.Finally,an active fractional order controller is proposed to control the new model at different fractional orders.The chaos of the new model is very useful and can be used to produce random keys for data encryption.

Graphene oxide-based hydrogels as a nanocarrier for anticancer drug delivery

Graphene oxide (GO) possesses excellent mechanical strength,biocompatibility,colloidal stability,large surface area and high adsorption capability.It has driven to cancer nanotechnology to defeat cancer therapy obstacles,via integration into three-dimensional (3D) hydrogel network with biocompatible polymers as nanocomposites carrier,and controllable release of anticancer drugs.Specifically,the surface of GO affords π-π stacking and hydrophilic interactions with anticancer drugs.Additionally,modification of GO with various polymers such as natural and synthetic polymers enhances its biodegradability,drug loading,and target delivery.In this review,GO based hydrogels research accomplishments are reviewed on the aspects of crosslinking strategies,preparation methods,the model drug,polymer conjugation and modification with targeting ligands.Moreover,swelling kinetics,drug release profile and biological activity in vivo and in vitro are discussed.The biocompatibility of GO based hydrogels is also discussed from the perspective of its nano-bio interfaces.Apart from that,the clinical potential of GO based hydrogels and its major challenges are addressed in detail.Finally,this review concludes with a summary and invigorating future perspectives of GO based hydrogels for anticancer drug delivery.It is anticipated that this review can stimulate a new research gateway to facilitate the development of anticancer drug delivery by harnessing the unique properties of GO based hydrogels,such as large surface area,chemical purity,high loading capacity of drug,chemical stability,and the nature of lipophilic for cell membrane penetration.

First-principles calculations of nitrogen-doped antimony triselenide： A prospective material for solar cells and infrared optoelectronic devices

This study is focused on calculation of the electronic structure and optical properties of non-metal doped Sb2Se3 using the first-principles method. One and two N atoms are introduced to Sb and Se sites in a Sb2Se3 crystal. When one and two N atoms are introduced into the Sb2Se3 lattice at Sb sites, the electronic structure shows that the doping significantly modifies the bandgap of Sb2Se3 from 1.11 eV to 0.787 and 0.685 eV, respectively. When N atoms are introduced to Se sites, the material shows a metallic behavior. The static dielectric constants el（0） for Sb16Se24, SblsN1Se24, Sb14N2Se24, Sb16Se23N1, and Sb16Se22N2 are 14.84, 15.54, 15.02, 18.9, and 39.29, respectively. The calculated values of the refractive index n（0） for Sb16Se24, SblsN1Se24, Sb14N2Se24, Sb16Se23N1, and Sb16Se22N2 are 3.83, 3.92, 3.86, 4.33, and 6.21, respectively. The optical absorbance and optical conductivity curves of the crystal for N-doping at Sb sites show a significant redshift towards the short-wave infrared spectral region as compared to N-doping at Se sites. The modulation of the static refractive index and static dielectric constant is mainly dependent on the doping level. The optical properties and bandgap narrowing effect suggest that the N-doped Sb2Se3is a promising new semiconductor and can be a replacement for GaSb due to its very similar bandgap and low cost.

Multi-media compartments for assessing ecological and health risks from concurrent exposure to multiple contaminants on Bhola Island,Bangladesh

In this study,a set of coupled multi-media compartments(i.e.,sediment,soil,water and vegetable)was used to assess ecological and health risks from the ingestion of 11 PTEs(Pb,Cd,Cr,As,Hg,Cu,Zn,Ni,Co,Fe,and Mn)and their transportation routes in the water-soil-plant system from the coastal Bhola Island,Bangladesh.The mean concentrations of Cd,Pb,and Co for soil and Cd,Co,and As for sediment were higher than their reference values.In contrast,Cd,Pb,and Ni concentrations in water surpassed the acceptable limits set by national and international laws and were considered unsuitable for drinking purposes.Vegetables demonstrated high Pb and Cd contents,demonstrating a potential food safety risk to the inhabitants.Results of principal component analysis(PCA)revealed that Cd,Pb,Hg,Cu,Ni and Zn sources were likely to be anthropogenic,especially agro-farming inputs,whereas the Fe,As,Cr,Mn,and Co sources were similar to natural origin.So,Cd,Pb and Co are the key contaminants in the study area and pose the elevated health and ecological risks in the coastal area.Cd and Pb exhibited higher ecological risks in soils and sediments,as Pb had the highest bio-accessibility(BA;0.02±0.003)and Cd possessed a high bioaccumulation factor(BCF;0.004±0.006).The self-organizing map analysis recognized three spatial patterns which are good agreement with PCA.The average hazard index(HI)values for soil were above the permissible level(HI>1)set by the respective agency;two times higher HI values were noticed for children than adults,suggesting children are highly susceptible to health risk.Continuous monitoring and source controls for Cd and Pb,along with agro-farming management practices,need to be implemented to reduce the risk of PTE contamination to the aquatic ecosystem and its inhabitants.

Preparation of epoxy resin/rare earth doped aluminate nanocomposite toward photoluminescent and superhydrophobic transparent woods

A translucent wooden substrate with long-lasting phosphorescence,high photostability and durability,tough surface,ultraviolet protection,high optical transmittance,and superhydrophobicity was developed.This long-lasting phosphorescent wooden substrate is able to continue emitting light for extended time periods.Lignin-modified wood(LMW)was immobilized with a solution of epoxy resin(ER)and rare-earth doped aluminate(REDA)phosphor nanoparticles(NPs).For an improved dispersion of pigment,REDA was synthesized in a nanoscale particle size,and characterized by transmission electron microscopy(TEM)to indicate a particle size of 8-14 nm.The crystal structure of REDA nanoparticles was also proved by X-ray diffraction(XRD).For an improved production of long-persistent phosphorescent colo rless woods,REDA must be well-dispersed in MAA without aggregation.Absorption and emissio n,as well as decay and lifetime spectra were explored.The morphologies of the wooden substrates with different ratios of REDA were investigated by scanning electron microscopy(SEM),X-ray fluorescence(XRF)analysis,Fourier transform infrared spectra(FT-IR),elemental mapping,and energy-dispersion Xray(EDXA).The phosphorescent woods show changes in color from colorless to green under ultraviolet(UV)irradiation,and to yellowish-green in the dark,as proved by the colorimetric parameters of the CIE Lab system.The afterglow wood samples display an absorbance band at 365 nm and two phosphorescent bands at 431 and 520 nm.Improved UV shielding,photostability,and hydrophobicity were explored.With increasing REDA ratio,both static contact and slide angles are found to improve in the ranges of147.6°-163.6°and 9°-14°,respectively.The long-lasting photoluminescence is optimized at a REDA ratio of 8%.The present strategy shows a large-scale production approach of multiple functional woods for many potential applications,such as smart glow in the dark windows and safety signs.

Au/MXene based ultrafast all-optical switching

All-optical switches have arisen great attention due to their ultrafast speed as compared with electric switches.However,the excellent optical properties and strong interaction of two-dimensional(2D)material MXene show great potentials in next-generation all-optical switching.As a solution,we propose all-optical switching used Au/MXene with switching full width at half maximum(FWHM)operating at 290 fs.Compared with pure MXene,the Au/MXene behaves outstanding performances due to local surface plasmon resonance(LSPR),including broadband differential transmission,strong near-infrared on/off ratio enhancement.Remarkably,this study enhances understanding of Au/MXene based ultrafast all-optical switching red-shifted about 34 nm in comparison to MXene,validating all optical properties of Au/MXene opening the way to the implementation of optical interconnection and optical switching.

Adsorption of rare earth elements onto diatomite M45:Experimental investigations and modeling with statistical physics theory

The separation of rare earth elements using diatomite M45 from aqueous solutions was studied.The experimental isotherms for the adsorption of trivalent lanthanum,cerium,and neodymium cations on this adsorbent were quantified under strongly acidic conditions(pH 2)at 298-328 K.The adsorption equilibria of these earth elements were analyzed using two statistical physics models(homogeneous and heterogeneous monolayer models).The results show that the adsorption of these ions implies a multiionic mechanism,which is exothermic.Si-containing functional groups are responsible for the adsorption of these rare-earth elements on the diatomite surface.A heterogeneous statistical physics model confirms that two Si-based functional groups participate in the separation of these cations.The calculated adsorption capacities at saturation follow the order:neodymium>cerium>lanthanum.Calculated interaction energies range from 28600 to 40100 J/mol,indicating physical adsorption on diatomite M45.This study demonstrates that diatomite M45 is a promising separation medium that can be used for the recovery of REEs dissolved in aqueous solutions via adsorption.

非贵金属单原子催化剂Co_(1)/MXene(Mo_(2)CS_(2))的CO氧化反应机理研究

MXene是一类由前过渡态金属碳化物、氮化物或碳氮化物构成的新型二维材料.我们利用量子化学方法研究了单原子Co在新型二维MXene材料Mo2CS2上的吸附构型、稳定性和催化性质.研究发现Co原子可以稳定锚定在MXene材料的表面,形成的单原子催化剂适合于催化低温CO氧化.计算表明,吸附的CO和O2分子与Co_(1)/Mo_(2)CS_(2)催化剂表面之间的电荷转移在活化这些小分子时起着重要作用.我们研究了Co1/Mo2CS2催化氧化CO的三种机理:Eley-Rideal(ER),Langmuir-Hinshelwood(LH)和Termolecular Eley-Rideal(TER),发现在低温下这三种反应机理都是可行的.其中在Co_(1)/Mo_(2)CS_(2)催化剂上TER机理具有最高的催化活性,计算的决速步能垒分别为0.67(TER),0.78(LH)和0.88 eV(ER).我们的研究结果表明,利用二维材料MXene发展和设计经济的、非贵金属单原子催化剂具有重要应用前景.