A review of interaction mechanisms and microscopic simulation methods for CO_(2)-water-rock system

This work systematically reviews the complex mechanisms of CO_(2)-water-rock interactions,microscopic simulations of reactive transport(dissolution,precipitation and precipitate migration)in porous media,and microscopic simulations of CO_(2)-water-rock system.The work points out the key issues in current research and provides suggestions for future research.After injection of CO_(2) into underground reservoirs,not only conventional pressure-driven flow and mass transfer processes occur,but also special physicochemical phenomena like dissolution,precipitation,and precipitate migration.The coupling of these processes causes complex changes in permeability and porosity parameters of the porous media.Pore-scale microscopic flow simulations can provide detailed information within the three-dimensional pore and throat space and explicitly observe changes in the fluid-solid interfaces of porous media during reactions.At present,the research has limitations in the decoupling of complex mechanisms,characterization of differential multi-mineral reactions,precipitation generation mechanisms and characterization(crystal nucleation and mineral detachment),simulation methods for precipitation-fluid interaction,and coupling mechanisms of multiple physicochemical processes.In future studies,it is essential to innovate experimental methods to decouple“dissolution-precipitation-precipitate migration”processes,improve the accuracy of experimental testing of minerals geochemical reaction-related parameters,build reliable characterization of various precipitation types,establish precipitation-fluid interaction simulation methods,coordinate the boundary conditions of different physicochemical processes,and,finally,achieve coupled flow simulation of“dissolution-precipitation-precipitate migration”within CO_(2)-water-rock systems.

Cu-based materials for electrocatalytic CO_(2) to alcohols:Reaction mechanism,catalyst categories,and regulation strategies

Electrocatalytic CO_(2) reduction reaction(CO_(2)RR)technology,which enables carbon capture storage and resource utilization by reducing CO_(2) to valuable chemicals or fuels,has become a global research hotspot in recent decades.Among the many products of CO_(2)RR(carbon monoxide,acids,aldehydes and alcohols,olefins,etc.),alcohols(methanol,ethanol,propanol,etc.)have a higher market value and energy density,but it is also more difficult to produce.Copper is known to be effective in catalyzing CO_(2) to high valueadded alcohols,but with poor selectivity.The progress of Cu-based catalysts for the selective generation of alcohols,including copper oxides,bimetals,single atoms and composites is reviewed.Meanwhile,to improve Cu-based catalyst activity and modulate product selectivity,the modulation strategies are straighten out,including morphological regulation,crystalline surface,oxidation state,as well as elemental doping and defect engineering.Based on the research progress of electrocatalytic CO_(2) reduction for alcohol production on Cu-based materials,the reaction pathways and the key intermediates of the electrocatalytic CO_(2)RR to methanol,ethanol and propanol are summarized.Finally,the problems of traditional electrocatalytic CO_(2)RR are introduced,and the future applications of machine learning and theoretical calculations are prospected.An in-depth discussion and a comprehensive review of the reaction mechanism,catalyst types and regulation strategies were carried out with a view to promoting the development of electrocatalytic CO_(2)RR to alcohols.

Effects of acid-rock reaction on physical properties during CO_(2)-rich industrial waste gas(CO_(2)-rich IWG)injection in shale reservoirs

"Carbon peaking and carbon neutrality"is an essential national strategy,and the geological storage and utilization of CO_(2)is a hot issue today.However,due to the scarcity of pure CO_(2)gas sources in China and the high cost of CO_(2)capture,CO_(2)-rich industrial waste gas(CO_(2)-rich IWG)is gradually emerging into the public's gaze.CO_(2)has good adsorption properties on shale surfaces,but acidic gases can react with shale,so the mechanism of the CO_(2)-rich IWG-water-shale reaction and the change in reservoir properties will determine the stability of geological storage.Therefore,based on the mineral composition of the Longmaxi Formation shale,this study constructs a thermodynamic equilibrium model of water-rock reactions and simulates the regularity of reactions between CO_(2)-rich IWG and shale minerals.The results indicate that CO_(2)consumed 12%after reaction,and impurity gases in the CO_(2)-rich IWG can be dissolved entirely,thus demonstrating the feasibility of treating IWG through water-rock reactions.Since IWG inhibits the dissolution of CO_(2),the optimal composition of CO_(2)-rich IWG is 95%CO_(2)and 5%IWG when CO_(2)geological storage is the main goal.In contrast,when the main goal is the geological storage of total CO_(2)-rich IWG or impurity gas,the optimal CO_(2)-rich IWG composition is 50%CO_(2)and 50%IWG.In the CO_(2)-rich IWG-water-shale reaction,temperature has less influence on the water-rock reaction,while pressure is the most important parameter.SO2 has the greatest impact on water-rock reaction in gas.For minerals,clay minerals such as illite and montmorillonite had a significant effect on water-rock reaction.The overall reaction is dominated by precipitation and the volume of the rock skeleton has increased by 0.74 cm3,resulting in a decrease in shale porosity,which enhances the stability of CO_(2)geological storage to some extent.During the reaction between CO_(2)-rich IWG-water-shale at simulated temperatures and pressures,precipitation is the main reaction,and shale porosity decreases.However,as the reservoir water content increases,the reaction will first dissolve and then precipitate before dissolving again.When the water content is less than 0.0005 kg or greater than 0.4 kg,it will lead to an increase in reservoir porosity,which ultimately reduces the long-term geological storage stability of CO_(2)-rich IWG.

Effects of surface chlorine atoms on charge distribution and reaction barriers for photocatalytic CO_(2)reduction

Photocatalytic CO_(2)reduction to produce high value-added carbon-based fuel has been proposed as a promising approach to mitigate global warming issues.However,the conversion efficiency and product selectivity are still low due to the sluggish dynamics of transfer processes involved in proton-assisted multi-electron reactions.Lowering the formation energy barriers of intermediate products is an effective method to enhance the selectivity and productivity of final products.In this study,we aim to regulate the surface electronic structure of Bi_(2)WO_(6)by doping surface chlorine atoms to achieve effective photocatalytic CO_(2)reduction.Surface Cl atoms can enhance the absorption ability of light,affect its energy band structure and promote charge separation.Combined with DFT calculations,it is revealed that surface Cl atoms can not only change the surface charge distribution which affects the competitive adsorption of H_(2)O and CO_(2),but also lower the formation energy barrier of intermediate products to generate more intermediate*COOH,thus facilitating CO production.Overall,this study demonstrates a promising surface halogenation strategy to enhance the photocatalytic CO_(2)reduction activity of a layered structure Bi-based catalyst.

Microstructure,interfacial reaction behavior,and mechanical properties of Ti_(3)AlC_(2)reinforced Al6061 composites

The interfacial reaction behavior of Al and Ti_(3)AlC_(2)at different pouring temperatures and its effect on the microstructure and mechanical properties of the composites were investigated.The results show that the addition of3.0 wt.%Ti_(3)AlC_(2)refines the average grain size ofα(Al)in the composite by 50.1%compared to Al6061 alloy.Morphological analyses indicate that an in-situ Al_(3Ti)transition layer of-180 nm in thickness is generated around the edge of Ti_(3)AlC_(2)at 720℃,forming a well-bonded Al-Al_(3Ti)interface.At this processing temperature,the ultimate tensile strength of A16061-3.0 wt.%Ti_(3)AlC_(2)composite is 199.2 MPa,an improvement of 41.5%over the Al6061 matrix.Mechanism analyses further elucidate that 720℃is favourable for forming the nano-sized transition layer at the Ti_(3)AlC_(2)edges.And,the thermal mismatch strengthening plays a dominant role in this state,with a strengthening contribution of about 74.8%.

In-situ elemental reaction-regulated Ag_(2)S films enable the best thermoelectric performances

Silver sulfide thinfilm,with excellent thermoelectric properties,is few reported due to the complex and time-consuming high-temperature or high-pressure synthesis process.Here,a fast ionic conductor n-type Ag2Sfilm with good crystallinity and uniform density is prepared by sputtering metal Agfilms of different thicknesses on glass and then reacting in S precursor solution at low temperature.At 450 K,β-Ag2Sfilms can be obtained and underwent a phase transition fromα-Ag2S monoclinic,which had a significant effect on their electrical and thermal properties.The grain size of Ag2Sfilms increases with the increase offilm thickness.Before and after the phase transition,the carrier concentration and mobility cause obvious changes in the electrical properties of Ag2S.The carrier concentration of body-centered cubic phaseβ-Ag2S is about three orders of magnitude higher than that of monoclinic phaseα-Ag2S,and the mobility is also 2–3 times that of the latter.Especially,after the phase transition,the conductivity ofβ-Ag2S rises exponentially from the zero conductivity ofα-Ag2S and increases with the increase of temperature.The Ag2Sfilm shows the highestfigure of merit of 0.830.30 at 600 K from the sample with±∼1600 nm thickness,which is the highest record among Ag2S-based thermoelectric materials reported so far.

Study of the reaction mechanism for preparing powdered activated coke with SO_(2)adsorption capability via one-step rapid activation method under flue gas atmosphere

In this study,the impact of different reaction times on the preparation of powdered activated carbon(PAC)using a one-step rapid activation method under flue gas atmosphere is investigated,and the underlying reaction mechanism is summarized.Results indicate that the reaction process of this method can be divided into three stages:stage I is the rapid release of volatiles and the rapid consumption of O_(2),primarily occurring within a reaction time range of 0-0.5 s;stage II is mainly the continuous release and diffusion of volatiles,which is the carbonization and activation coupling reaction stage,and the carbonization process is the main in this stage.This stage mainly occurs at the reaction time range of 0.5 -2.0 s when SL-coal is used as material,and that is 0.5-3.0 s when JJ-coal is used as material;stage III is mainly the activation stage,during which activated components diffuse to both the surface and interior of particles.This stage mainly involves the reaction stage of CO_(2)and H2O(g)activation,and it mainly occurs at the reaction time range of 2.0-4.0 s when SL-coal is used as material,and that is 3.0-4.0 s when JJ-coal is used as material.Besides,the main function of the first two stages is to provide more diffusion channels and contact surfaces/activation sites for the diffusion and activation of the activated components in the third stage.Mastering the reaction mechanism would serve as a crucial reference and foundation for designing the structure,size of the reactor,and optimal positioning of the activator nozzle in PAC preparation.

Healing the structural defects of spinel MnFe_(2)O_(4) to enhance the electrocatalytic activity for oxygen reduction reaction

Spinel metal oxides containing Mn,Co,or Fe(AB_(2)O_(4),A/B=Mn/Fe/Co)are one of the most promising nonPt electrocatalysts for oxygen reduction reaction(ORR)in alkaline conditions.However,the low conductivity of metal oxides and the poor intrinsic activities of transition metal sites lead to unsatisfactory ORR performance.In this study,eutectic molten salt(EMS)treatment is employed to reconstruct the atomic arrangement of MnFe_(2)O_(4)electrocatalyst as a prototype for enhancing ORR performance.Comprehensive analyses by using XAFS,soft XAS,XPS,and electrochemical methods reveal that the EMS treatment reduces the oxygen vacancies and spinel inverse in MnFe_(2)O_(4)effectively,which improves the electric conductivity and increases the population of more catalytically active Mn^(2+)sites with tetrahedral coordination.Moreover,the enhanced Mn-O interaction after EMS treatment is conducive to the adsorption and activation of O_(2),which promotes the first electron transfer step(generally considered as the ratedetermining step)of the ORR process.As a result,the EMS treated MnFe_(2)O_(4)catalyst delivers a positive shift of 40 mV in the ORR half-wave potential and a two-fold enhanced mass/specific activity.This work provides a convenient approach to manipulate the atomic architecture and local electronic structure of spinel oxides as ORR electrocatalysts and a comprehensive understanding of the structureperformance relationship from the molecular/atomic scale.

Shock-induced chemical reaction characteristics of PTFE-Al-Bi_(2)O_(3)reactive materials

A ternary system of PTFE/Al/Bi_(2)O_(3)is constructed by incorporating PTFE-based reactive material and thermite for enhancing the energy release of the PTFE-based reactive material.The effects of Bi_(2)O_(3)in the PTFE/Al/Bi_(2)O_(3)on both mechanical properties and the energy release were investigated through various tests such as thermogravimetry-differential scanning calorimetry,adiabatic oxygen bomb test and split Hopkinson pressure bar test.The microstructure observed through scanning electron microscope and Xray diffraction results are used to analyze the ignition and reaction mechanism of PTFE/Al/Bi_(2)O_(3).The results indicate that the PTFE/Al/Bi_(2)O_(3)are capable of triggering the exothermic reaction of molten PTFE/Bi_(2)O_(3)and Al/Bi_(2)O_(3)over the PTFE/Al reactive materials,thereby promoting reactions.The excessive aluminum in the ternary system is beneficial for increasing energy release.The ignition of shock-induced chemical reactions in PTFE/Al/Bi_(2)O_(3)is closely related to the material fracture.The dominant mechanism for hot-spot generation under Split Hopkinson Pressure Bar test is the frictional temperature rise at the microcrack after failure.

Accelerating the Screening of Modified MA_(2)Z_(4) Catalysts for Hydrogen Evolution Reaction by Deep Learning-Based Local Geometric Analysis

Machine learning(ML)integrated with density functional theory(DFT)calculations have recently been used to accelerate the design and discovery of single-atom catalysts(SACs)by establishing deep structure–activity relationships.The traditional ML models are always difficult to identify the structural differences among the single-atom systems with different modification methods,leading to the limitation of the potential application range.Aiming to the structural properties of several typical two-dimensional MA_(2)Z_(4)-based single-atom systems(bare MA_(2)Z_(4) and metal single-atom doped/supported MA_(2)Z_(4)),an improved crystal graph convolutional neural network(CGCNN)classification model was employed,instead of the traditional machine learning regression model,to address the challenge of incompatibility in the studied systems.The CGCNN model was optimized using crystal graph representation in which the geometric configuration was divided into active layer,surface layer,and bulk layer(ASB-GCNN).Through ML and DFT calculations,five potential single-atom hydrogen evolution reaction(HER)catalysts were screened from chemical space of 600 MA_(2)Z_(4)-based materials,especially V_(1)/HfSn_(2)N_(4)(S)with high stability and activity(Δ_(GH*)is 0.06 eV).Further projected density of states(pDOS)analysis in combination with the wave function analysis of the SAC-H bond revealed that the SAC-dz^(2)orbital coincided with the H-s orbital around the energy level of−2.50 eV,and orbital analysis confirmed the formation ofσbonds.This study provides an efficient multistep screening design framework of metal single-atom catalyst for HER systems with similar two-dimensional supports but different geometric configurations.

Differences in CO_(2)-Water-Rock Chemical Reactions among ’Sweet Spot’ Reservoirs:Implications for Carbon Sequestration

The Lucaogou Formation,located in the Jimsar Sag,Junggar Basin,NW China,has great potential for shale oil resources.In the process of CO_(2)-EOR(CO_(2) enhance oil recovery),mineral dissolution,precipitation and transformation,leading to the local corrosion or blockage of reservoirs,have a significant influence on recovery.In this study,a combination of high-temperature and high-pressure laboratory experiments and coupled temperature/fluid-chemistry multifield numerical simulations are used to investigate CO_(2)-water-rock reactions under various reservoir conditions in the upper and lower ’sweet spots’,to reveal the mechanisms underlying CO_(2)-induced mineral dissolution,precipitation and transformation.In addition,we quantitatively calculated the evolution of porosity over geological timescales;compared and analyzed the variability of CO_(2) transformation in the reservoir under a variety of temperature,lithology and solution conditions;and identified the main factors controlling CO_(2)-water-rock reactions,the types of mineral transformation occurring during long-term CO_(2) sequestration and effective carbon sequestration minerals.The results demonstrate that the main minerals undergoing dissolution under the influence of supercritical CO_(2) are feldspars,while the main minerals undergoing precipitation include carbonate rock minerals,clay minerals and quartz.Feldspar minerals,especially the initially abundant plagioclase in the formation,directly affects total carbon sequestration,feldspar-rich clastic rocks therefore having considerable sequestration potential.

CO_(2)快速吞吐提高页岩油采收率现场试验

页岩油注CO_(2)吞吐提高采收率技术处于探索阶段,目前面临着CO_(2)与页岩储层及流体相互作用机制不明确、数值模拟技术不成熟、缺乏规模注采及低成本回收工艺等技术难题。为探索页岩油注CO_(2)提高采收率主控机理,以苏北盆地溱潼凹陷古近系阜宁组二段页岩油为对象开展了超临界CO_(2)水岩反应实验,分析了高温高压条件下页岩矿物溶蚀作用及其对孔隙度和渗透率的影响,并通过注CO_(2)恒质膨胀实验、最小混相压力测试评价了地层超压条件下注CO_(2)后原油高压物性变化特征,并在此基础上开展考虑多因素数值模拟研究优化了设计注入参数,最终通过矿场试验验证了技术可行性。研究结果表明:(1) CO_(2)水岩反应以碳酸质矿物溶蚀占主导,长英质矿物部分溶解,生成中大孔隙;(2)在地层原油中注入适量的CO_(2),显著萃取了原油中间烃组分,原油黏度从5.151 mPa·s下降到1.250 mPa·s,且CO_(2)首先萃取轻烃组分,随生产时间增加萃取组分逐渐变为重烃;(3)基于人工压裂与天然缝网混合介质组分数模模型,优化设计单井吞吐注气量1.7×10~4 t,注气速度500~600 t/d,焖井时间50 d;(4)低压侧加热的页岩油CO_(2)吞吐地面工艺,可依据CO_(2)注入地面工艺多参数数据模型,实现精准控温,避免注入管线冻堵及井下油管和套管材料低温脆断问题;(5)产出气CO_(2)浓度高于80%时,采用气相回收直注工艺,实现产出气回收成本降至104元/t。结论认为,CO_(2)快速吞吐有效提高了页岩油采收率,形成的机理认识和技术系列可为页岩油注CO_(2)吞吐开发提供参考和借鉴。

原位合成TiB_(2)颗粒增强铝基复合材料研究进展

原位合成技术制备的铝基复合材料,权衡了强度和塑性间的矛盾,有望实现铝基复合材料的结构功能一体化。原位合成TiB_(2)颗粒增强铝基复合材料比刚度,比模量高,具有优异的力学性能、耐腐蚀性能、耐磨性能和抗疲劳性能,是近年来金属基复合材料的研究热点之一,在汽车制造、高铁动车、航空航天和国防军事等领域具有广阔的应用前景。归纳了三种原位合成TiB_(2)颗粒增强铝基复合材料反应体系(Al-K_(2)TiF_(6)-KBF_(4)体系、Al-TiO_(2)-B_(2)O_(3)体系和Al-Ti-B体系)的特点和优势,概述了原位合成TiB_(2)颗粒对铝基体晶粒尺寸、界面结合和润湿性产生影响的研究现状,对TiB_(2)颗粒强化铝复合材料力学性能的作用机制展开了讨论,梳理总结现阶段在此领域研究过程中仍未解决的问题,展望TiB_(2)颗粒增强铝基复合材料的潜在发展空间,以期为研究和开发原位合成颗粒增强铝基复合材料提供参考。

基于三维点云计算的CO_(2)-水-岩反应程度量化表征方法

CO_(2)地质封存是减少大气中CO_(2)排放,降低温室效应的重要途径,CO_(2)注入含水地层中时,CO_(2)-水-岩反应可能引起岩石矿物的侵蚀,对CO_(2)地质封存安全性产生显著影响。在室内实验中,通过表征岩石表面的形貌特征可以有效地评估CO_(2)-水-岩反应程度,为CO_(2)地质封存的安全性评估提供科学依据。通过三维点云计算可以精确量化地表征CO_(2)-水-岩反应程度,这种方法首先运用三维激光扫描技术,构建岩石表面的三维模型,确定CO_(2)-水处理前岩石表面三维模型的基准面,并基于处理前的均方根粗糙度确定处理后岩石表面三维模型的基准面。基于三维模型点云信息,提出了两种不同的体积计算新方法,并通过对规则模型体积的计算比较了两种计算方法的准确性与适用性,可根据实际情况选择两种计算方法量化表征CO_(2)-水处理前后岩石表面的侵蚀体积。最后,以陕西省咸阳市某煤矿煤样为例,开展了CO_(2)-水-岩反应模拟试验,验证了计算的可行性。试验结果表明:该文提出的侵蚀体积计算方法可有效地量化表征CO_(2)-水-岩反应程度,CO_(2)-水处理后岩石表面不同区域的侵蚀差异性明显,岩石表面的侵蚀体积与均方根粗糙度之间存在显著的正比关系,随着均方根粗糙度的增大,侵蚀体积也相应上升。

达格列净联合二甲双胍治疗初诊2型糖尿病患者的效果

目的:观察达格列净联合二甲双胍治疗治疗初诊2型糖尿病(T2DM)患者的效果。方法:选取2021年5月至2023年4月该院收治的106例初诊T2DM患者进行前瞻性研究,根据随机数字表法将其分为观察组(n=53)与对照组(n=53)。对照组给予二甲双胍治疗,观察组在对照组基础上联合达格列净治疗,比较两组临床疗效、治疗前后糖代谢指标[餐后2 h血糖(2hPG)、糖化血红蛋白(HbAlc)、空腹胰岛素(FINS)、胰岛素抵抗指数(HOMA-IR)、胰岛素分泌指数(HOMA-β)]水平、炎性指标[C反应蛋白(CRP)、同型半胱氨酸(Hcy)]水平和不良反应发生率。结果:观察组治疗总有效率为94.34%(50/53),高于对照组的81.13%(43/53),差异有统计学意义(P<0.05);治疗后,两组HbAlc、2hPG、HOMA-IR水平均低于治疗前,且观察组低于对照组,两组FINS、HOMA-β水平均高于治疗前,且观察组高于对照组,差异有统计学意义(P<0.05);治疗后,两组CRP、Hcy水平均低于治疗前,且观察组低于对照组,差异有统计学意义(P<0.05);两组不良反应发生率比较,差异无统计学意义(P>0.05)。结论:达格列净联合二甲双胍治疗初诊T2DM患者可提高治疗总有效率,改善糖代谢指标水平,降低炎性指标水平,其效果优于单纯二甲双胍治疗。

水热反应温度对ZnIn_(2)S_(4)/Bi_(2)WO_(6)复合催化剂的影响研究

为解决传统半导体光催化剂可见光响应能力弱、光生电子空穴复合快、能带结构导致载流子氧化还原能力弱等问题,采用水热法制备ZnIn_(2)S_(4)/Bi_(2)WO_(6)(ZlS@BW)复合催化剂并系统研究水热反应温度对其结构性能的影响。当水热温度从80℃升高到160℃,ZlS@BW复合光催化剂结晶度提高,形貌转变为致密核壳结构,比表面积和光电性能先降低再升高,氟伐他汀去除率逐步上升。而当温度升高到200℃时,核壳结构遭到了破坏,比表面积和光电性能变差,氟伐他汀的降解效果降低,光催化性能下降。结果表明,水热温度为160℃时,制备的ZlS@BW复合光催化剂晶型结晶程度较高,且形貌致密,比表面积最大,产生的瞬态光电流最大,阻抗半径最小,具有最优光催化性能。对污染物氟伐他汀降的降解效率最高,可达到75.47%。

2-氨基苯甲酰胺衍生物的合成与应用

以2-氨基苯甲腈衍生物(2a~2f)为原料,在氢氧化钾碱性条件下发生水解反应合成了2-氨基苯甲酰胺衍生物(1a~1f),对合成条件进行了优化,通过1 HNMR对产物结构进行了表征。结果表明,在氢氧化钾用量n(KOH)∶n(2a)为4∶1、回流反应14 h的最佳条件下,衍生物1a的收率达到84%;以多聚磷酸为催化剂,衍生物1a与苯甲醛在微波辅助下可以合成7-甲基-2-苯基-2,3-二氢喹唑啉-4(1 H)-酮(3)。

水热反应条件对SnO_(2)/Bi_(2)WO_(6)复合材料光催化活性的影响

本文以不同水热条件制备了正交晶系结构的两种二氧化锡和一种钨酸铋,并制备出了两种由纳米片组成的花状团簇的二氧化锡/钨酸铋复合光催化材料。通过X射线衍射仪、扫描电子显微镜、比表面积孔隙度测试仪、紫外可见分光光度计等手段对三种样品的样貌、比表面积、孔隙度、孔体积及吸光度测试表征。用碘钨灯来模拟太阳光,研究对比以不同水热条件下制备的钨酸铋以及两种二氧化锡/钨酸铋复合材料作催化剂催化降解罗丹明B的光催化性能。综合实验数据分析,发现二氧化锡/钨酸铋复合样品的衍射峰与钨酸铋样品的衍射峰一致,不同的水热条件会影响产物的物相结构,但对晶体结构和结晶度无影响。光催化360 min时,水热条件为180℃、12 h的钨酸铋对罗丹明B的降解率是33%、水热条件为180℃、6 h的二氧化锡和180℃、12 h的钨酸铋制备的复合物样品1对罗丹明B的降解率是46%、水热条件为180℃、12 h的二氧化锡和180℃、12 h的钨酸铋制备的复合物样品2对罗丹明B的降解率是57%。二氧化锡/钨酸铋复合样品的催化效果优于纯钨酸铋,同时也说明不同水热反应条件对复合光催化材料的催化性能有一定的影响。

清热祛浊方联合二甲双胍治疗2型糖尿病疗效分析

目的探究清热祛浊方联合二甲双胍治疗痰湿瘀热型2型糖尿病及对炎性因子的影响。方法选取2020年1月—2021年1月北省沧州中西医结合医院收治的130例痰湿瘀热型2型糖尿病患者,随机分为试验组和对照组,各65例。对照组予以常盐酸二甲双胍治疗,试验组在西药治疗基础上加用自拟清热祛浊方。2组均治疗3个月。比较2组临床疗效、中医证候积分、空腹血糖(FPG)、餐后2 h血糖(2 hPG)、糖化血红蛋白(HbAlc)及超敏C反应蛋白(hs-CRP)、白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)、胰岛素抵抗(IR)。结果治疗后,试验组总有效率为93.85%,对照组总有效率为81.54%,试验组高于对照组(P<0.05);2组中医证候积分、FPG、2 hPG、HbAlc、hs-CRP、IL-6、TNF-α、IR均降低(P<0.05),试验组均低于对照组(P<0.05)。结论清热祛浊方联合二甲双胍治疗痰湿瘀热型2型糖尿病可提高临床疗效,降低血糖和炎症反应,值得推广。

不同表面结构氧化铟催化CO_(2)加氢制甲醇的反应机理

IN_(2)O_(3)对CO_(2)加氢合成甲醇具有较好的催化活性,为了进一步阐明IN_(2)O_(3)的失活机理与甲醇合成的构效关系,选择了立方晶相IN_(2)O_(3)的不同表面,采用密度泛函理论(DFT)研究了H_(2)还原无氧空位的IN_(2)O_(3)完美表面生成氧空位的反应机理,模拟了IN_(2)O_(3)催化剂在氢气作用下失活形成In团簇的微观过程。选择抗烧结性较好的IN_(2)O_(3)(111)阶梯表面,研究了CO_(2)的吸附活化以及甲醇生成的反应机理。结果表明:随着IN_(2)O_(3)表面氧空位数目的增加,H_(2)还原IN_(2)O_(3)的反应能垒升高,H_(2)解离成为氧空位生成的限速步骤;带有缺陷的IN_(2)O_(3)(111)阶梯表面具有较好的反应活性和抗烧结性能;CO_(2)加氢生成HCOO^(*)的反应路径是甲醇合成的优势路线,其中,bi-HCOO^(*)加氢生成bi-H_(2)CO^(*)并同时脱氧填补氧空位的过程为反应的限速步骤。