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Preparation of titanium dioxide/silver sulfate powder and its antibacterial activity 被引量:1
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作者 彭兵 苑春 +3 位作者 柴立元 韦顺文 于延芬 苏维丰 《中国有色金属学会会刊:英文版》 EI CSCD 2005年第5期1156-1160,共5页
Antibacterial powders of titanium dioxide/silver sulfate were produced by heat-treatment of the metatitanic acid, as precursor, into which the silver nitrate was added. The influences of heating temperature on the str... Antibacterial powders of titanium dioxide/silver sulfate were produced by heat-treatment of the metatitanic acid, as precursor, into which the silver nitrate was added. The influences of heating temperature on the structure and composition of the product were investigated through XRD and SEM. The results show that the powder is spherical in the phase of TiO2-Ag2SO4. The granularity of the particles increases from 10.7nm to 28.7nm with the temperature of heat-treatment increasing from 300℃ to 800℃. The antibacterial activity of the powder was judged in the way of the minimum inhibitory contents (MiCs). When the content of silver sulfate is less than 2%, the photocatalysis of titanium dioxide and silver ions cooperate to kill bacteria. And the MiCs decrease and keep around 1.0×10 -41.5×10 -4 constantly with the increase of silver content. Furthermore, the MiCs decrease with the increase of temperature of heat-treatment when the temperature is lower than 500℃. But when the temperature is beyond 600℃ the MiCs increase quickly, which shows the inferior antibacterial performance. 展开更多
关键词 二氧化钛 硫酸盐 抗菌活性 环境友好性
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Research progress on the kinetics of methane-carbon dioxide reforming catalyzed by nickel-based catalysts
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作者 HU Jingtao WU Jie +2 位作者 DENG Bangqiang LIU Dawei XU Long 《燃料化学学报(中英文)》 北大核心 2026年第2期21-45,共25页
Under the backdrop of“Carbon Peak and Carbon Neutrality”(dual carbon)goal in China,the methane-carbon dioxide reforming reaction has attracted considerable attention due to its environmental benefits of converting t... Under the backdrop of“Carbon Peak and Carbon Neutrality”(dual carbon)goal in China,the methane-carbon dioxide reforming reaction has attracted considerable attention due to its environmental benefits of converting two greenhouse gases(methane and carbon dioxide)into syngas and its promising industrial applications.Nickel(Ni)-based catalysts,with high catalytic activity,low cost,and abundant resources,are considered ideal candidates for industrial applications.In this article,three reaction kinetic models were briefly introduced,namely the Power-Law(PL)model,the Eley-Rideal(ER)model,and the Langmuir-Hinshelwood-Hougen-Watson(LHHW)model.Based on the LHHW model,the reaction kinetics and mechanisms of different catalytic systems were systematically discussed,including the properties of supports,the doping of noble metals and transition metals,the role of promoters,and the influence of the geometric and electronic structures of Ni on the reaction mechanism.Furthermore,the kinetics of carbon deposition and elimination on various catalysts were analyzed.Based on the reaction rate expressions for carbon elimination,the reasons for the high activity of transition metal iron(Fe)-doped catalysts and core-shell structured catalysts in carbon elimination were explained.Based on the detailed collation and comparative analysis of the reaction mechanisms and kinetic characteristics across diverse Ni-based catalytic systems,a theoretical guidance for the designing of high-performance catalysts was provided in this work. 展开更多
关键词 carbon dioxide reforming of methane CATALYST model KINETICS carbon deposit
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Dietary titanium dioxide particles(E171)promote colitis-associated colorectal cancer development in mice through macrophage-derived S100A8/S100A9 secretion mediated by NLRP3/Caspase 1/GSDMD pathway
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作者 Ping Wang Yan Zhong +3 位作者 Jingquan Liu Lingfang Gao Ting Long Zuguo Li 《Chinese Journal of Natural Medicines》 2026年第2期215-226,共12页
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
关键词 Titanium dioxide particles(E171) Colitis-associated colorectal cancer MACROPHAGE S100A8/S100A9 NLRP3/Caspase 1/GSDMD
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Synthesis, characteristics, and antibacterial activity of a rare-earth samarium/silver/titanium dioxide inorganic nanomaterials 被引量:6
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作者 吴江 张国梁 +6 位作者 刘杰 高蕻冰 宋春香 杜浩然 张丽 巩忠萍 吕玉光 《Journal of Rare Earths》 SCIE EI CAS CSCD 2014年第8期727-732,共6页
An inorganic nanomaterials combination of Sm, Ag, and TiO2 was synthesized using supercritical fluid drying (SCFD) combined with solgel techniques. The structure, photocatalysis and bacteriostatic activity of the ma... An inorganic nanomaterials combination of Sm, Ag, and TiO2 was synthesized using supercritical fluid drying (SCFD) combined with solgel techniques. The structure, photocatalysis and bacteriostatic activity of the materials were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XRPS), photocatalytic performance, and antibacterial activity experiments. The XRD results showed that the average particle diameter of Sm/Ag/TiO2 was 14.62 nm and Ag and Sm ions were dispersed on the surface of TiO2 in a highly dispersed, amorphous form. The TEM image showed that the size of the particle was 12 nm using the scherer formula. The XPS result showed that the element Sm was doped and Ag was loaded inorganic nanomaterials successfully. Sm/Ag/TiO2 exhibited optimal photocatalytic properties at 600 oC, the photocatalytic optimal proportion of Sm/Ag/TiO2 was 2:2:100. When the molar ratio was 2:2:100, the bacteriostatic circle diameter was 16 mm for Staphylococcus aureus, the minimum bacteriostatic concentration was 200μg/mL for white beads coccus, and the minimum bactericidal concentration was 2×10^4μg/mL for white beads coccus. The SEM results showed that the antibacterial material attached to the candida albicans cell surface, cells appeared fold deformation. Therefore the inorganic nanomaterials Sm/Ag/TiO2 had high temperature resistance, good photocatalytic and antibacterial characteristics in visible light. 展开更多
关键词 inorganic nanomaterials samarium/silver/titanium dioxide PHOTOCATALYTIC antibacterial activities rare earths
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Solubility of the silver nitrate in supercritical carbon dioxide with ethanol and ethylene glycol as double cosolvents: Experimental determination and correlation 被引量:1
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作者 Hongrui Ren Jibin Song +1 位作者 Qinqin Xu Jianzhong Yin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第2期400-404,共5页
Solubility of the silver nitrate in the supercritical carbon dioxide containing ethanol and ethylene glycol as double cosolvents was measured under certain pressure and temperature range(10–25 MPa, 323.15–333.15 K).... Solubility of the silver nitrate in the supercritical carbon dioxide containing ethanol and ethylene glycol as double cosolvents was measured under certain pressure and temperature range(10–25 MPa, 323.15–333.15 K). The impact of the pressure and temperature on the solubility was also investigated. Based on the experiment data,a correlation model concerning solid's solubility in supercritical fluids was established by combining the solubility parameter with the thermodynamic equation when a binary interaction parameter and a mixed solvent solubility parameter were defined. Experiments show the solubility of AgNO_3 increases with the pressure at a certain temperature. However, the influence of temperature is related to a pressure defined as the turnover pressure(12.3 MPa). When the pressure is higher(or lower) than this turnover pressure, silver nitrate's solubility shows increasing(or decreasing) trend as the temperature rises. Satisfactory accuracy of our presented model was revealed by comparing experimental data with calculated results. 展开更多
关键词 SUPERCRITICAL carbon dioxide silver NITRATE SOLUBILITY parameter CORRELATION model
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Investigation of the formation processes of CO_(2) hydrate films on the interface of liquid carbon dioxide with humic acids solutions 被引量:1
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作者 Aleksey K.Sagidullin Sergey S.Skiba +1 位作者 Tatyana P.Adamova Andrey Y.Manakov 《Chinese Journal of Chemical Engineering》 2025年第3期53-61,共9页
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
关键词 HYDRATES Carbon dioxide Humic acids solutions Reaction kinetics Liquid liquid reaction Film growth
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Separation/Enrichment of Copper and Silver Using Titanium Dioxide Nanoparticles Coated with Poly-Thiophene and Their Analysis by Flame Atomic Absorption Spectrophotometry 被引量:1
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作者 Mohammad Behbahani Meysam Babapour +4 位作者 Mostafa M. Amini Omid Sadeghi Akbar Bagheri Mani Salarian Banafsheh Rafiee 《American Journal of Analytical Chemistry》 2013年第2期90-98,共9页
We report on the use of titanium dioxide nanoparticles (NPs) coated with poly-thiophene for the preconcentration of copper and silverions. The NPs were prepared by first modifying the surface of TiO2 NPs with vinyl gr... We report on the use of titanium dioxide nanoparticles (NPs) coated with poly-thiophene for the preconcentration of copper and silverions. The NPs were prepared by first modifying the surface of TiO2 NPs with vinyl groups and then copolymerizing them with vinyl thiophen. The resulting TiO2-polythiophene core-shell NPs were characterized by thermogravimetry, differential thermal analysis, scanning electron microscopy, Fourier transform infrared spectrometry and X-ray diffraction. The experimental conditions such as pH value, adsorption and desorption time, type, concentration and volume of the eluent, break through volume, and effect of potentially interfering ions were optimized. The ions were then desorbed with hydrochloric acid and determined by FAAS. The limits of detection are 0.4 and 1.2 μg·L_1 for Cu(II) and Ag(I), respectively, and recoveries and precisions are >98.0% 展开更多
关键词 Novel Poly-Thiophene-TiO2 Nanoparticles COPPER silver Flame Atomic Absorption SPECTROPHOTOMETRY
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Preparation of Cyclic Carbonates from Carbon Dioxide and Epoxides Catalyzed by Bifunctional Molybdenum Complexes
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作者 Wang Tao Tao Sheng +4 位作者 Chen Fei Du Zhihong Bo Chunbo Li Min Liu Ning 《有机化学》 北大核心 2025年第12期4354-4361,共8页
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
关键词 molybdenum catalyst EPOXIDE carbon dioxide cyclic carbonate
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A mechanistic study of ciprofloxacin adsorption by goethite in the presence of silver and titanium dioxide nanoparticles
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作者 Jie Tang Yun Wang +5 位作者 Qiang Xue Fei Liu Kenneth CCarroll Xiaohua Lu Taogeng Zhou Dengjun Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2022年第8期46-56,共11页
The adsorption behaviors of ciprofloxacin(CIP),a fluoroquinolone antibiotic,onto goethite(Gt)in the presence of silver and titanium dioxide nanoparticles(AgNPs and TiO_(2)NPs)were investigated.Results showed that CIP ... The adsorption behaviors of ciprofloxacin(CIP),a fluoroquinolone antibiotic,onto goethite(Gt)in the presence of silver and titanium dioxide nanoparticles(AgNPs and TiO_(2)NPs)were investigated.Results showed that CIP adsorption kinetics in Gt with or without NPs both followed the pseudo-second-order kinetic model.The presence of AgNPs or TiO_(2)NPs inhibited the adsorption of CIP by Gt.The amount of inhibition of CIP sorption due to AgNPs was decreased with an increase of solution pH from 5.0 to 9.0.In contrast,in the presence of TiO_(2)NPs,CIP adsorption by Gt was almost unchanged at pHs of 5.0∼6.5 but was decreased with an increase of pH from 6.5 to 9.0.The mechanisms of AgNPs and TiO_(2)NPs in inhibiting CIP adsorption by Gt were different,which was attributed to citrate coating of AgNPs resulting in competition with CIP for adsorption sites on Gt,while TiO_(2)NPs could compete with Gt for CIP adsorption.Additionally,CIP was adsorbed by Gt or TiO_(2)NPs through a tridentate complex involving the bidentate inner-sphere coordination of the deprotonated carboxylic group and hydrogen bonding through the adjacent carbonyl group on the quinoline ring.These findings advance our understanding of the environmental behavior and fate of fluoroquinolone antibiotics in the presence of NPs. 展开更多
关键词 CIPROFLOXACIN GOETHITE silver nanoparticles Titanium dioxide nanoparticles ADSORPTION
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Improving CO_(2) solubility in a hybrid sorbent of 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide/mesoporous titanium dioxide/water with confinement effect
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作者 Haoran Yin Lili Mu +3 位作者 Yifeng Chen Licheng Li Kang Sun Xiaoyan Ji 《Chinese Journal of Chemical Engineering》 2025年第4期100-109,共10页
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
关键词 Ionic liquid Carbon dioxide Mesoporous titanium dioxide Confinement effect Thermodynamics
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Near Gas-Water Contact Sequestration of Carbon Dioxide to Improve the Performance of Water Drive Gas Reservoir: Case Study
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作者 Mohammad Amin Safarzadeh Hossein Zangeneh Javad Kasravi 《Computational Water, Energy, and Environmental Engineering》 2025年第1期1-15,共15页
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
关键词 Gas Reservoir Water Encroachment Residual Gas Saturation Aquifer Influx Carbon dioxide Sequestration Hazardous Water Production
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Silver-catalyzed carboxylative cyclization of alkynic hydrazones with carbon dioxide
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作者 Wenzhen Zhang Yuqian Sun +2 位作者 Min Zhang Hui Zhou Xiaobing Lu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第8期1153-1159,共7页
The development of new catalytic methodologies to synthesize heterocyclic fine chemicals using carbon dioxide as a synthon has attracted considerable attention. Herein, we report the silver( I)-catalyzed carboxylative... The development of new catalytic methodologies to synthesize heterocyclic fine chemicals using carbon dioxide as a synthon has attracted considerable attention. Herein, we report the silver( I)-catalyzed carboxylative cyclization of a variety of alkynic hydrazones with carbon dioxide to produce the corresponding 1,3,4-oxadiazin-2-ones under mild reaction conditions. In this reaction, silver(I) salts play a π-Lewis acid role for the highly efficient activation of the alkyne moiety in the hydrazone substrates. Single-crystal X-ray analysis and NOE experiments confirm that the newly formed oxadiazinone products exhibit Z configuration. Based on control experiments and NMR studies, a mechanism including the formation of a reactive carbazate intermediate, electrophilic cyclization, and subsequent protonation is proposed. This study offers an efficient and atom- economical method for the synthesis of biologically important 1,3,4-oxadiazin-2-ones. 展开更多
关键词 Carbon dioxide silver catalysis Carboxylative cyclization Alkynic hydrazine Oxadiazinone Homogeneous catalysis
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Photocatalytic single electron reduction of CO_(2)into carbon dioxide radical anion(CO_(2)^(·-)):Generation,detection and chemical utilization
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作者 Pratibha Saini Krishan Kumar +5 位作者 Surendra Saini Mukul Sethi Priyanka Meena Aditya Gurjar Wolfgang Weigand Vijay Parewa 《Journal of Energy Chemistry》 2025年第6期525-559,I0012,共36页
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
关键词 Carbon dioxide Carbon dioxide radical anion Single-electron reduction VISIBLE-LIGHT Carboxylation reactions
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Measurement of Carbon Dioxide and Sulfur Dioxide in Soil Gases as a Guide to Mineral Exploration under Exotic Overburden
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作者 WAN Wei FAN Huihu +3 位作者 CHU Kelei CHENG Zhizhong WANG Mingqi ZUO Libo 《Acta Geologica Sinica(English Edition)》 2025年第5期1494-1508,共15页
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
关键词 gas measurement concealed deposit carbon dioxide sulfur dioxide rapid gas analyzer
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Synthesis and Crystal Structure of a Tetranuclear Silver Complex with Bis(diphenylphosphino) amine-dioxide as a Tridentate Ligand
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作者 尹刚强 魏巧华 陈忠宁 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第3期253-256,共4页
The tetranuclear complex[Ag4(μ-Ph2PNHPPh2)2(μ-OPh2PNPPh2O)2] (PF6)2·CH3COCH3 containing bis(diphenylphosphino)amine (Ph2PNHPPh2) and deprotonated bis- (diphenylphosphino)amine-dioxide (OPh2PNPPh2O... The tetranuclear complex[Ag4(μ-Ph2PNHPPh2)2(μ-OPh2PNPPh2O)2] (PF6)2·CH3COCH3 containing bis(diphenylphosphino)amine (Ph2PNHPPh2) and deprotonated bis- (diphenylphosphino)amine-dioxide (OPh2PNPPh2O) was isolated and characterized by X-ray crystallography. The deprotonated OPh2PNPPh2O acts as a tridentate ligand in a chelating and bridging mode. Two of the four Ag atoms are in a trigonal planar environment composed of PO2 chromophore, whereas the other two are coordinated with PN donors in a distorted linear arrangement. The title complex (C51H47Ag2F6N2O3P5) crystallizes in triclinic, space group P1^- with a = 12.9552 (2), b = 14.1691(3), c = 15.8110(3)A°, α = 68.7500(10), β= 86.8840(10), γ = 75.6170(10)°, V= 2618.16 (8) A°^3, Mr= 1220.50, Z = 2, Dc= 1.548 g/cm^3, F(000) = 1228 and μ(MoKα) = 0.965 mm^-1. The final refinements converged at R = 0.0679 and wR = 0.1528 for 7001 observed reflections (I〉 2σ(I)). 展开更多
关键词 bis(diphenylphosphino)amine bis(diphenylphosphino)amine-dioxide crystal structure silver
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Thermal decomposition behavior and kinetics of magnesite under carbon dioxide atmosphere
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作者 Ze Gong Dexi Wang +1 位作者 Xueyi Ma Lihua Fan 《Chinese Journal of Chemical Engineering》 2025年第11期197-203,共7页
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
关键词 Carbon dioxide Reaction kinetics MAGNESITE PYROLYSIS THERMOGRAVIMETRY
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Research progress on carbon dioxide embolism during laparoscopic liver resection
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作者 Zhitao Xie Weiqi Li +4 位作者 Bingzhi Dong Zihao Huang Chenqi Jin Hong Yu Xin Yu 《Laparoscopic, Endoscopic and Robotic Surgery》 2025年第4期171-177,共7页
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
关键词 Carbon dioxide EMBOLISM LAPAROSCOPY Liver resection Transesophageal echocardiogram
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Green innovation unleashed:Harnessing tungsten-based nanomaterials for catalyzing solar-driven carbon dioxide conversion
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作者 Weidan Meng Yanbo Zhou Yi Zhou 《Chinese Chemical Letters》 2025年第2期108-117,共10页
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
关键词 Carbon dioxide photoreduction Tungsten-based nanocatalyst Mechanism Performance evaluation Selectivity
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2D and 3D phthalocyanine covalent organic frameworks for electrocatalytic carbon dioxide reduction
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作者 Qi Zhang Bin Han +3 位作者 Yucheng Jin Mingrun Li Enhui Zhang Jianzhuang Jiang 《Chinese Chemical Letters》 2025年第9期659-663,共5页
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
关键词 PHTHALOCYANINE Dimensionality Covalent organic framework ELECTROCATALYSIS Carbon dioxide reduction
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Photo Catalytic Degradation of Concrete Containing Titanium Dioxide Nanoparticles—A Review
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作者 Jegatheeswaran Dhanapal Sridevi Saravanan +1 位作者 Sindhuja Padmanaban Madhan Padmanaban 《Journal of Building Material Science》 2025年第3期1-15,共15页
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
关键词 ANTIBACTERIAL CONCRETE Nano Titanium dioxide Photocatalytic Property Self-Cleaning Concrete
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