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Gas-phase electrocatalytic reduction of carbon dioxide using electrolytic cell based on phosphoric acid-doped polybenzimidazole membrane 被引量:3
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作者 Dunfeng Gao Fan Cai +3 位作者 Qinqin Xu Guoxiong Wang Xiulian Pan Xinhe Bao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2014年第6期694-700,共7页
Carbon dioxide transformation to fuels or chemicals provides an attractive approach for its utilization as feedstock and its emission reduction. Herein, we report a gas-phase electrocatalytic reduction of CO2 in an el... Carbon dioxide transformation to fuels or chemicals provides an attractive approach for its utilization as feedstock and its emission reduction. Herein, we report a gas-phase electrocatalytic reduction of CO2 in an electrolytic cell, constructed using phosphoric acid-doped polybenz- imidazole (PBI) membrane, which allowed operation at 170 ℃ Pt/C and PtMo/C with variable ratio of Pt/Mo were studied as the cathode catalysts. The results showed that PtMo/C catalysts significantly enhanced CO formation and inhibited CH4 formation compared with Pt/C catalyst. Characterization by X-ray diffraction, X-ray photoelectron spectroscopy and transmission electron microscopy revealed that most Mo species existed as MoO3 in PtMo/C catalysts and the interaction between Pt and MoOx was likely responsible for the enhanced CO formation rate although these bicomponent catalysts in general had a larger particle size than Pt/C catalyst. 展开更多
关键词 carbon dioxide gas-phase electrocatalytic reduction platinum-molybdenum catalyst Faradaic efficiency formation rate
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Synthesis of dimethyl carbonate by gas-phase oxidative carbonylation of methanol in the presence of solid catalyst I. Catalyst preparation and catalytic Properties 被引量:2
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作者 Wang Yanji Zhao Xinqiang +1 位作者 Yuan Baoguo Zhang Bingchang and Cong Jinsheng(Department of Chemical Engineering, Hebci University) of Technology300130 Tianjin Parole’s Republic of China) 《河北工业大学学报》 CAS 1997年第A01期100-109,共10页
The gas-phase synthesis of dimethyl carbonate (DMC) from methanol, carbon monoxide and oXygen has here Studied in a flow system at atomspheric Pressure. A series of Catalyst used in this reaCtion have been prepared an... The gas-phase synthesis of dimethyl carbonate (DMC) from methanol, carbon monoxide and oXygen has here Studied in a flow system at atomspheric Pressure. A series of Catalyst used in this reaCtion have been prepared and evaluated. The influence of trivared carbon supporters, alkaline metal Promoters and operation conditions on DMC opthesis reaction has been discussed. Under the conditions of 130℃, CO/O2=1 .96, SV=3340h-1, the space-time yield (STY) of DMC over PdCl2-CuCl2-CH3COOK/ac. catalyst is 217g/l-cat h,which is higher than what is published in the literatUre so far. 展开更多
关键词 DIMETHYL CARBONATE synthesis Solid catalyst METHANOL gas-phase OXIDATIVE carbonylation.
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Gas-phase dehydrochlorination of 1, 1, 2, 2-tetrachloroethane over the non-metal supported ionic liquid catalyst 被引量:2
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作者 Pengze Zhang Yangzhen Jin +3 位作者 Zhaobin Jiang Guanqun Xie Qunfeng Zhang Xiaonian Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第6期1623-1627,共5页
Developing of non-metallic catalyst to replace metal catalyst is a meaningful and challenging direction.In this work,the non-metallic catalyst was synthetized successfully by loading ionic liquid onto the silica surfa... Developing of non-metallic catalyst to replace metal catalyst is a meaningful and challenging direction.In this work,the non-metallic catalyst was synthetized successfully by loading ionic liquid onto the silica surface,which was applied for the gas-phase dehydrochlorination of 1,1,2,2-tetrachloroethane.The 12%TPPC/SiO2(wt%)showed the best results with the conversion of 1,1,2,2-tetrachloroethane reaching 100%.The selectivity of 1,1,2-trichloroethylene was 100%,and no deactivation was found during the evaluation period.The catalytic mechanism was investigated and possible reaction route was given,which was a reference for fabricating and design of solid base catalyst. 展开更多
关键词 Dehydrochlorination catalyst Supported ionic liquids gas-phase catalysis Base catalysis
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Influence of heat treatment on microstructure and electrochemical behaviors of Mg-Zn binary alloys prepared by gas-phase alloying technique 被引量:2
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作者 MA Jun NIU Li-bin +2 位作者 YAN Yu-ting GAO Chong WANG Xiao-gang 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第3期762-771,共10页
Mg-Zn binary alloys fabricated by the gas-phase alloying technique under vacuum condition were investigated in the state of initial state and after heat treatment for the microstructure and electrochemical behaviors.D... Mg-Zn binary alloys fabricated by the gas-phase alloying technique under vacuum condition were investigated in the state of initial state and after heat treatment for the microstructure and electrochemical behaviors.Different from the traditional Mg-Zn alloys preparation methods,alloys prepared by gas-phase alloying have a large number of intermetallic compounds,such as MgZn,Mg7Zn3 and MgZn2.After solution treatment,the boundary of the eutectic disappeared and the size ofα-Mg increased from 100μm to 150μm.At the same time,the value of the resistance of charge transfer increased,which indicates that the resistance of the charge transfer and the corrosion resistance of the alloys increased.After artificial aging treatment,the distribution ofα-Mg was more uniform and its size was reduced to about 50μm,and there was new eutectic structure formed.The newly formed eutectic structure forms galvanic cells with the alloy matrix,which makes the corrosion resistance of the alloy weaken. 展开更多
关键词 gas-phase alloying Mg-Zn alloy heat treatment Ringer’s solution electrochemical behavior
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Anaerobic digestion of kitchen wastes in a single-phased anaerobic sequencing batch reactor(ASBR) with gas-phased absorb of CO_2 被引量:1
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作者 ZHANGBo HEZheng-guang +3 位作者 ZHANGLi-li XUJian-bo SHIHong-zhuan CAIWei-min 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第2期249-255,共7页
The performance of the single-stage anaerobic digestion of kitchen wastes was investigated in an anaerobic sequencing batch reactor(ASBR) with gas-phased absorb of CO 2. The ASBR was operated at four chemical oxygen ... The performance of the single-stage anaerobic digestion of kitchen wastes was investigated in an anaerobic sequencing batch reactor(ASBR) with gas-phased absorb of CO 2. The ASBR was operated at four chemical oxygen demand(COD) loading rates, 2.8, 5.1, 6.2 and 8.4 g/(L·d) respectively. The COD loading rate was increased with the TS concentration and HRT changing. At maximum COD loading rate of 8.4 g/(L·d), the COD, total solid(TS) removal rate and methane gas yield were 69%, 68% and 2.5 L/(L·d) respectively. The operation of the reactor with gas-phased absorb of CO 2 was stable in spite of the low pH(2.6—3.9) and high concentration of TS(142 g/L) of input mixture. The output volatile fatty acid(VFA) concentration was between 2.7—4.7 g/L and had no inhibition on the methanogenic microorganism. The reactor without gas-phased absorb of CO 2 became acidified when the total COD loading rate was increased to 5.1 g/(L·d). Stoichiometry of the methanogenesis for kitchen wastes showed a considerable amount of alkaline will be required to keep pH in the appropriate range for the methanogenic microorganism based on theoretical calculation. Gas-phased absorb of CO 2 effectively reduced the alkaline consumption, hence avoided excessive cation into the reactor. 展开更多
关键词 kitchen wastes METHANOGENESIS gas-phased CO 2
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Industrial Preparation and Acid Resistance of Ultra-stable Y Zeolite with Small Cell Size Produced by Gas-phase Method 被引量:1
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作者 Zhang Jing Jia Jishun +4 位作者 Sha Hao Lu Guanqun Yan Jiasong Wang Shengji Zhou Lingping 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2022年第2期85-90,共6页
Small-cell HSY-S zeolite prepared by the gas-phase ultra-stable method had been researched and developed,and industrial preparation tests of HSY-S have been successfully carried out for the first time.The acid resista... Small-cell HSY-S zeolite prepared by the gas-phase ultra-stable method had been researched and developed,and industrial preparation tests of HSY-S have been successfully carried out for the first time.The acid resistance of industrially prepared HSY-S was investigated by acid solutions with different pH values.The structures and properties of HSY-S and its acid-treated samples were characterized by XRD,XRF,BET,and IR.Results show that the HSY-S samples have the characteristics of high crystallinity,good stability,large specific surface area,and good acid resistance. 展开更多
关键词 zeolite small unit cell size gas-phase ultra-stable acid resistance industrial preparation
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Gas-phase CO_(2)activation with single electrons,metal atoms,clusters,and molecules 被引量:1
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作者 Ruijing Wang Gaoxiang Liu +2 位作者 Seong Keun Kim Kit H.Bowen Xinxing Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第12期130-137,I0003,共9页
In this review,the history and outlook of gas-phase CO_(2)activation using single electrons,metal atoms,clusters(mainly metal hydride clusters),and molecules are discussed on both of the experimental and theoretical f... In this review,the history and outlook of gas-phase CO_(2)activation using single electrons,metal atoms,clusters(mainly metal hydride clusters),and molecules are discussed on both of the experimental and theoretical fronts.Although the development of bulk solid-state materials for the activation and conversion of CO_(2)into value-added products have enjoyed great success in the past several decades,this review focuses only on gas-phase studies,because isolated,well-defined gas-phase systems are ideally suited for high-resolution experiments using state-of-the-art spectrometric and spectroscopic techniques,and for simulations employing modern quantum theoretical methods.The unmatched high complementarity and comparability of experiment and theory in the case of gas-phase investigations bear an enormous potential in providing insights in the reactions of CO_(2)activation at the atomic level.In all of these examples,the reduction and bending of the inert neutral CO_(2)molecule is the critical step determined by the frontier orbitals of reaction participants.Based on the results and outlook summarized in this review,we anticipate that studies of gas-phase CO_(2)activations will be an avenue rich with opportunities for the rational design of novel catalysts based on the knowledge obtained on the atomic level. 展开更多
关键词 CO_(2)activation CO_(2)anion gas-phase cluster Electronic structure
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The structure optimization of gas-phase surface discharge and its application for dye degradation 被引量:1
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作者 曹颖 李杰 +3 位作者 姜楠 吴彦 商克峰 鲁娜 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第5期131-138,共8页
A gas-phase surface discharge(GSD)was employed to optimize the discharge reactor structure and investigate the dye degradation.A dye mixture of methylene blue,acid orange and methyl orange was used as a model pollut... A gas-phase surface discharge(GSD)was employed to optimize the discharge reactor structure and investigate the dye degradation.A dye mixture of methylene blue,acid orange and methyl orange was used as a model pollutant.The results indicated that the reactor structure of the GSD system with the ratio of tube inner surface area and volume of 2.48,screw pitch between a high-voltage electrode of 9.7 mm,high-voltage electrode wire diameter of 0.8 mm,dielectric tube thickness of2.0 mm and tube inner diameter of 16.13 mm presented a better ozone(O_3)generation efficiency.Furthermore,a larger screw pitch and smaller wire diameter enhanced the O_3generation.After the dye mixture degradation by the optimized GSD system,73.21%and 50.74%of the chemical oxygen demand(COD)and total organic carbon removal rate were achieved within 20 min,respectively,and the biochemical oxygen demand(BOD)and biodegradability(BOD/COD)improved. 展开更多
关键词 gas-phase surface discharge (GSD) structure optimization ozone (O3) dye degradation
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Pore throat structure heterogeneity and its effect on gas-phase seepage capacity in tight sandstone reservoirs:A case study from the Triassic Yanchang Formation,Ordos Basin 被引量:1
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作者 Yu-Bin Yang Wen-Lian Xiao +8 位作者 Ling-Li Zheng Qi-Hong Lei Chao-Zhong Qin You-An He Shuai-Shuai Liu Min Li Yong-Ming Li Jin-Zhou Zhao Meng Chen 《Petroleum Science》 SCIE EI CSCD 2023年第5期2892-2907,共16页
The microscopic heterogeneity of pore-throat structures in tight sandstone is a crucial parameter for understanding the transport mechanism of fluid flow.In this work,we firstly developed the new procedure to characte... The microscopic heterogeneity of pore-throat structures in tight sandstone is a crucial parameter for understanding the transport mechanism of fluid flow.In this work,we firstly developed the new procedure to characterize the pore size distribution(PSD)and throat size distribution(TSD)by combining the nuclear magnetic resonance(NMR),cast thin section(CTS),and constant-rate mercury injection(CRMI)tests,and used the permeability estimated model to verify the full-scale PSD and TSD.Then,we respectively analyzed the fractal feature of the pore and throat,and characterized the heterogeneity of pores and throats.Finally,we elaborated the effect of the pore and throat heterogeneity on the gas-phase seepage capacity base on the analysis of the simple capillary tube model and gas-flooding experiment.The results showed that(1)The PSD and TSD of the tight sandstone sample ranged from 0.01 to 10 mm and from 0.1 to 57 mm,respectively,mainly contributed by the micropores and mesopores.Meanwhile,the permeability estimated by the PSD and TSD was consistent with the experimental permeability,and relative error was lower than 8%.(2)The PSD and TSD exhibited multifractal characteristics,and singularity strength range,Δα,could be used as the indicator for characterizing the heterogeneity of pore and throat.Furthermore,the throat of the sample showed stronger heterogeneity than that the pore.(3)The throats played an important role for the fluid transport in the tight sandstone,and the effect of the throat heterogeneity on the gas-phase seepage capacity was different under the lower and higher injection pressure.The macropores and micropores maybe respectively become the preferential migration pathways at the lower and higher injection pressure.In the end,the identification plate was established in our paper,and could be described the relationship among the throat heterogeneity,injection pressure,permeability and flow path of the gas phase in the tight sandstone. 展开更多
关键词 Tight sandstone Pore size distribution(PSD) Throat size distribution(TSD) Pore and throat heterogeneity gas-phase flow capacity Nuclear magnetic resonance(NMR) Constant-rate mercury injection(CRMI)
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A Condensed Gas-Phase Chemical Model and Its Application
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作者 王体健 孙照渤 李宗恺 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1999年第4期608-618,共11页
Using the 'lumped mechanism' and 'counting species' methods, we developed a condensed gas-phase chemical model based on a simplified one. The modified quasi-steady-state approximation (QSSA) scheme and... Using the 'lumped mechanism' and 'counting species' methods, we developed a condensed gas-phase chemical model based on a simplified one. The modified quasi-steady-state approximation (QSSA) scheme and the error redistribution mass conservation technique are adopted to solve the atmospheric chemistry kinetic equations. Results show that the condensed model can well simulate concentration variations of gas species such as SO2, NOX, O-3, H2O2 and conversion rates of SO2 and NOX transformation to H2SO4 and HNO3. These results are in good agreement with those from the simplified model. The conversion rates of SO2 and NOX under different initial concentrations and meteorological conditions are computed, and the results can be directly applied to regional acid deposition model. 展开更多
关键词 gas-phase chemistry conversion rate
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NOX -Catalyzed Gas-Phase Activation of Methane: the Formation of Hydrogen
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作者 Chaoxian Xiao, Zhen Yan, Yuan KouCollege of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2003年第2期90-92,共3页
NO_x-catalyzed oxidation of methane without a solid catalyst wasinvestigated, and a hydrogen selectivity of 27% was obtained with an overall methane conversion of34% and a free O_2 concentration of 1.7% at 700℃.
关键词 gas-phase oxidation methane activation METHANE nitrogen oxide HYDROGEN
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Understanding and controlling the variables for stromal vascular fraction therapy 被引量:1
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作者 Naveen Jeyaraman Sandeep Shrivastava +3 位作者 VR Ravi Arulkumar Nallakumarasamy Aditya Pundkar Madhan Jeyaraman 《World Journal of Stem Cells》 SCIE 2024年第8期784-798,共15页
In regenerative medicine,the isolation of mesenchymal stromal cells(MSCs)from the adipose tissue’s stromal vascular fraction(SVF)is a critical area of study.Our review meticulously examines the isolation process of M... In regenerative medicine,the isolation of mesenchymal stromal cells(MSCs)from the adipose tissue’s stromal vascular fraction(SVF)is a critical area of study.Our review meticulously examines the isolation process of MSCs,starting with the extraction of adipose tissue.The choice of liposuction technique,anatomical site,and immediate processing are essential to maintain cell functionality.We delve into the intricacies of enzymatic digestion,emphasizing the fine-tuning of enzyme concentrations to maximize cell yield while preventing harm.The review then outlines the filtration and centrifugation techniques necessary for isolating a purified SVF,alongside cell viability assessments like flow cytometry,which are vital for confirming the efficacy of the isolated MSCs.We discuss the advantages and drawbacks of using autologous vs allogeneic SVF sources,touching upon immunocompatibility and logistical considerations,as well as the variability inherent in donor-derived cells.Anesthesia choices,the selection between hypo-dermic needles vs liposuction cannulas,and the role of adipose tissue lysers in achieving cellular dissociation are evaluated for their impact on SVF isolation.Centrifugation protocols are also analyzed for their part in ensuring the integrity of the SVF.The necessity for standardized MSC isolation protocols is highlighted,promoting reproducibility and successful clinical application.We encourage ongoing research to deepen the understanding of MSC biology and therapeutic action,aiming to further the field of regenerative medicine.The review concludes with a call for rigorous research,interdisciplinary collaboration,and strict adherence to ethical and regulatory standards to safeguard patient safety and optimize treatment outcomes with MSCs. 展开更多
关键词 Mesenchymal stromal cells Stromal vascular fraction Adipose tissue Autologous stromal vascular fraction Stromal vascular fraction isolation
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Interaction between systemic iron parameters and left ventricular structure and function in the preserved ejection fraction population:a two-sample bidirectional Mendelian randomization study 被引量:1
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作者 Xiong-Bin MA Yong-Ming LIU +1 位作者 Yan-Lin LV Lin QIAN 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第1期64-80,共17页
BACKGROUND Left ventricular(LV)remodeling and diastolic function in people with heart failure(HF)are correlated with iron status;however,the causality is uncertain.This Mendelian randomization(MR)study investigated th... BACKGROUND Left ventricular(LV)remodeling and diastolic function in people with heart failure(HF)are correlated with iron status;however,the causality is uncertain.This Mendelian randomization(MR)study investigated the bidirectional causal relationship between systemic iron parameters and LV structure and function in a preserved ejection fraction population.METHODS Transferrin saturation(TSAT),total iron binding capacity(TIBC),and serum iron and ferritin levels were extracted as instrumental variables for iron parameters from meta-analyses of public genome-wide association studies.Individuals without myocardial infarction history,HF,or LV ejection fraction(LVEF)<50%(n=16,923)in the UK Biobank Cardiovascular Magnetic Resonance Imaging Study constituted the outcome dataset.The dataset included LV end-diastolic volume,LV endsystolic volume,LV mass(LVM),and LVM-to-end-diastolic volume ratio(LVMVR).We used a two-sample bidirectional MR study with inverse variance weighting(IVW)as the primary analysis method and estimation methods using different algorithms to improve the robustness of the results.RESULTS In the IVW analysis,one standard deviation(SD)increased in TSAT significantly correlated with decreased LVMVR(β=-0.1365;95%confidence interval[CI]:-0.2092 to-0.0638;P=0.0002)after Bonferroni adjustment.Conversely,no significant relationships were observed between other iron and LV parameters.After Bonferroni correction,reverse MR analysis showed that one SD increase in LVEF significantly correlated with decreased TSAT(β=-0.0699;95%CI:-0.1087 to-0.0311;P=0.0004).No heterogeneity or pleiotropic effects evidence was observed in the analysis.CONCLUSIONS We demonstrated a causal relationship between TSAT and LV remodeling and function in a preserved ejection fraction population. 展开更多
关键词 fraction function PARAMETERS
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Efficacy of stromal vascular fraction for knee osteoarthritis:A prospective,single-centre,non-randomized study with 2 years follow-up 被引量:2
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作者 Madhan Jeyaraman Naveen Jeyaraman +4 位作者 Tarun Jayakumar Swaminathan Ramasubramanian Rajni Ranjan Saurabh Kumar Jha Ashim Gupta 《World Journal of Orthopedics》 2024年第5期457-468,共12页
BACKGROUND Current osteoarthritis(OA)treatments focus on symptom relief without addressing the underlying disease process.In regenerative medicine,current treatments have limitations.In regenerative medicine,more rese... BACKGROUND Current osteoarthritis(OA)treatments focus on symptom relief without addressing the underlying disease process.In regenerative medicine,current treatments have limitations.In regenerative medicine,more research is needed for intra-articular stromal vascular fraction(SVF)injections in OA,including dosage optimization,long-term efficacy,safety,comparisons with other treatments,and mechanism exploration.AIM To compare the efficacy of intra-articular SVF with corticosteroid(ICS)injections in patients with primary knee OA.METHODS The study included 50 patients with Kellgren-Lawrence grades II and III OA.Patients were randomly assigned(1:1)to receive either a single intra-articular SVF injection(group A)or a single intra-articular ICS(triamcinolone)(group B)injection.Patients were followed up at 1,3,6,12,and 24 months.Visual analog score(VAS)and International Knee Documentation Committee(IKDC)scores were administered before the procedure and at all followups.The safety of SVF in terms of adverse and severe adverse events was recorded.Statistical analysis was performed with SPSS Version 26.0,IBM Corp,Chicago,IL,United States.RESULTS Both groups had similar demographics and baseline clinical characteristics.Follow-up showed minor patient loss,resulting in 23 and 24 in groups A and B respectively.Group A experienced a notable reduction in pain,with VAS scores decreasing from 7.7 to 2.4 over 24 months,compared to a minor reduction from 7.8 to 6.2 in Group B.This difference in pain reduction in group A was statistically significant from the third month onwards.Additionally,Group A showed significant improvements in knee functionality,with IKDC scores rising from 33.4 to 83.10,whereas Group B saw a modest increase from 36.7 to 45.16.The improvement in Group A was statistically significant from 6 months and maintained through 24 months.CONCLUSION Our study demonstrated that intra-articular administration of SVF can lead to reduced pain and improved knee function in patients with primary knee OA.More adequately powered,multi-center,double-blinded,randomised clinical trials with longer follow-ups are needed to further establish safety and justify its clinical use. 展开更多
关键词 Knee osteoarthritis Adipose tissue Stromal vascular fraction Regenerative medicine Orthobiologics
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Intermittent disturbance mechanical behavior and fractional deterioration mechanical model of rock under complex true triaxial stress paths 被引量:3
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作者 Zhi Zheng Hongyu Xu +3 位作者 Kai Zhang Guangliang Feng Qiang Zhang Yufei Zhao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第1期117-136,共20页
Mechanical excavation,blasting,adjacent rockburst and fracture slip that occur during mining excavation impose dynamic loads on the rock mass,leading to further fracture of damaged surrounding rock in three-dimensiona... Mechanical excavation,blasting,adjacent rockburst and fracture slip that occur during mining excavation impose dynamic loads on the rock mass,leading to further fracture of damaged surrounding rock in three-dimensional high-stress and even causing disasters.Therefore,a novel complex true triaxial static-dynamic combined loading method reflecting underground excavation damage and then frequent intermittent disturbance failure is proposed.True triaxial static compression and intermittent disturbance tests are carried out on monzogabbro.The effects of intermediate principal stress and amplitude on the strength characteristics,deformation characteristics,failure characteristics,and precursors of monzogabbro are analyzed,intermediate principal stress and amplitude increase monzogabbro strength and tensile fracture mechanism.Rapid increases in microseismic parameters during rock loading can be precursors for intermittent rock disturbance.Based on the experimental result,the new damage fractional elements and method with considering crack initiation stress and crack unstable stress as initiation and acceleration condition of intermittent disturbance irreversible deformation are proposed.A novel three-dimensional disturbance fractional deterioration model considering the intermediate principal stress effect and intermittent disturbance damage effect is established,and the model predicted results align well with the experimental results.The sensitivity of stress states and model parameters is further explored,and the intermittent disturbance behaviors at different f are predicted.This study provides valuable theoretical bases for the stability analysis of deep mining engineering under dynamic loads. 展开更多
关键词 True triaxial static and disturbance test Mechanical properties Failure mechanism and precursor Intermittent disturbance effect fractional mechanical model
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AB INITIO STUDY ON GAS-PHASE FACTION OF Ca WITH HN_3
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作者 (Rong Shun ZHU Shu Shan DAI(Department of Chemistry,Yunnan University.Kunming 650091.) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第6期581-584,共4页
The reaction of Ca with HN3 has been investigated theoretically by an ah initio MO methodwith electron correlation being taken into account by second-order MLLER-PLESSET(MP2)perturbation theory Two possible product ch... The reaction of Ca with HN3 has been investigated theoretically by an ah initio MO methodwith electron correlation being taken into account by second-order MLLER-PLESSET(MP2)perturbation theory Two possible product channels. CaN3+H. CaNH+N2, on the potential energysurfaces(PESs) have been examined and the reaction mechanism discussed. Values of tile HN-NZ,HN3, Ca-N3 and Ca-AH bond dissociation energy are also calculated, which are in good agreement withexperiment 展开更多
关键词 GAS HN AB INITIO STUDY ON gas-phase FACTION OF Ca WITH HN3 CA
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Ethyl acetate fraction of Sargassum pallidum extract attenuates particulate matter-induced oxidative stress and inflammation in keratinocytes and zebrafish 被引量:1
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作者 Wook Chul Kim Ji-Won Park +3 位作者 Bohyun Yun WonWoo Lee Kyung-Min Choi Seung-Hong Lee 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第4期137-146,共10页
Objective:To evaluate the effect of the ethyl acetate fraction derived from Sargassum pallidum extract against particulate matter(PM)-induced oxidative stress and inflammation in HaCaT cells and zebrafish.Methods:HaCa... Objective:To evaluate the effect of the ethyl acetate fraction derived from Sargassum pallidum extract against particulate matter(PM)-induced oxidative stress and inflammation in HaCaT cells and zebrafish.Methods:HaCaT cells and zebrafish were used to evaluate the protective effects of the ethyl acetate fraction of Sargassum pallidum extract against PM-induced oxidative stress and inflammation.The production of nitric oxide(NO),intracellular ROS,prostaglandin E_(2)(PGE_(2)),and pro-inflammatory cytokines,and the expression levels of COX-2,iNOS,and NF-κB were evaluated in PM-induced HaCaT cells.Furthermore,the levels of ROS,NO,and lipid peroxidation were assessed in the PM-exposed zebrafish model.Results:The ethyl acetate fraction of Sargassum pallidum extract significantly decreased the production of NO,intracellular ROS,and PGE_(2) in PM-induced HaCaT cells.In addition,the fraction markedly suppressed the levels of pro-inflammatory cytokines and inhibited the expression levels of COX-2,iNOS,and NF-κB.Furthermore,it displayed remarkable protective effects against PM-induced inflammatory response and oxidative stress,represented by the reduction of NO,ROS,and lipid peroxidation in zebrafish.Conclusions:The ethyl acetate fraction of Sargassum pallidum extract exhibits a protective effect against PM-induced oxidative stress and inflammation both in vitro and in vivo and has the potential as a candidate for the development of pharmaceutical and cosmeceutical products. 展开更多
关键词 Particulate matter INFLAMMATION Oxidative stress Sargassum pallidum Ethyl acetate fraction ZEBRAFISH
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2-42 Gas-phase Chemistry Study of Ruthenium and Rhodium Carbonyls
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作者 Cao Shiwei Qin Zhi Wang Yang 《IMP & HIRFL Annual Report》 2014年第1期82-83,共2页
In this work, gas-phase chemistry of ruthenium and rhodium was studied using online isothermal chromatographyapparatus at low temperature coupled to the 252Cf SF source[1] at IMP (Fig. 1). Apart from the interferenceo... In this work, gas-phase chemistry of ruthenium and rhodium was studied using online isothermal chromatographyapparatus at low temperature coupled to the 252Cf SF source[1] at IMP (Fig. 1). Apart from the interferenceof precursor effect[2], 109?110Ru and 111?112Rh were chosen as the representative isotopes for the two elementsrespectively. An improved Monte Carlo molecular simulation program was compiled according to the gas-phasechemistry model[3], and was used in the optimization of the experimental condition. The adsorption enthalpies ofpentacarbonyl ruthenium and tetracarbonyl rhodium on the FEP surface were obtained. 展开更多
关键词 gas-phase CHEMISTRY STUDY
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GAS-PHASE ION-MOLECULE REACTIONS OF BUCKMINSTERFULLERENE(C_(60))WITH Si(CH_3)_n CL_(4-n)(n=2,3)IN MASS SPECTROMETER
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作者 Xing Hua GUO Zi Yang LIU Shu Ying LIU Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun,130022 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第9期797-800,共4页
Reactions of C60 with Si(CH_3)_nCl_(4-n) (n=2,3)in the ion source of the mass spectrometer have been studied.The corresponding adduct ions[C60Si(CH_3)_mCl3_(-m)]^+(m=1,2,3),[C60SiCl]^+ and[C60CH_3]^+ were observed and... Reactions of C60 with Si(CH_3)_nCl_(4-n) (n=2,3)in the ion source of the mass spectrometer have been studied.The corresponding adduct ions[C60Si(CH_3)_mCl3_(-m)]^+(m=1,2,3),[C60SiCl]^+ and[C60CH_3]^+ were observed and their possible structures were discussed.The results indicated that C60 is very reactive to electrophiles in the gas phase. 展开更多
关键词 n=2 3)IN MASS SPECTROMETER WITH Si CH3 n CL N ION CL gas-phase ION-MOLECULE REACTIONS OF BUCKMINSTERFULLERENE SICI
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Model reduction of fractional impedance spectra for time–frequency analysis of batteries, fuel cells, and supercapacitors 被引量:1
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作者 Weiheng Li Qiu-An Huang +6 位作者 Yuxuan Bai Jia Wang Linlin Wang Yuyu Liu Yufeng Zhao Xifei Li Jiujun Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期108-141,共34页
Joint time–frequency analysis is an emerging method for interpreting the underlying physics in fuel cells,batteries,and supercapacitors.To increase the reliability of time–frequency analysis,a theoretical correlatio... Joint time–frequency analysis is an emerging method for interpreting the underlying physics in fuel cells,batteries,and supercapacitors.To increase the reliability of time–frequency analysis,a theoretical correlation between frequency-domain stationary analysis and time-domain transient analysis is urgently required.The present work formularizes a thorough model reduction of fractional impedance spectra for electrochemical energy devices involving not only the model reduction from fractional-order models to integer-order models and from high-to low-order RC circuits but also insight into the evolution of the characteristic time constants during the whole reduction process.The following work has been carried out:(i)the model-reduction theory is addressed for typical Warburg elements and RC circuits based on the continued fraction expansion theory and the response error minimization technique,respectively;(ii)the order effect on the model reduction of typical Warburg elements is quantitatively evaluated by time–frequency analysis;(iii)the results of time–frequency analysis are confirmed to be useful to determine the reduction order in terms of the kinetic information needed to be captured;and(iv)the results of time–frequency analysis are validated for the model reduction of fractional impedance spectra for lithium-ion batteries,supercapacitors,and solid oxide fuel cells.In turn,the numerical validation has demonstrated the powerful function of the joint time–frequency analysis.The thorough model reduction of fractional impedance spectra addressed in the present work not only clarifies the relationship between time-domain transient analysis and frequency-domain stationary analysis but also enhances the reliability of the joint time–frequency analysis for electrochemical energy devices. 展开更多
关键词 battery fuel cell supercapacitor fractional impedance spectroscopy model reduction time-frequency analysis
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