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Comparative Analysis of Reaction to Fire and Flammability of Hemp Shives Insulation Boards with Incorporated Microencapsulated Phase Change Materials
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作者 Inga Zotova Edgars Kirilovs Laura Ziemele 《Journal of Renewable Materials》 EI CAS 2024年第3期603-613,共11页
Nowadays buildings contain innovative materials,materials from local resources,production surpluses and rapidly renewable natural resources.Phase Change Materials(PCM)are one such group of novel materials which reduce... Nowadays buildings contain innovative materials,materials from local resources,production surpluses and rapidly renewable natural resources.Phase Change Materials(PCM)are one such group of novel materials which reduce building energy consumption.With the wider availability of microencapsulated PCM,there is an opportunity to develop a new type of insulating materials,combinate PCM with traditional insulation materials for latent heat energy storage.These materials are typically flammable and are located on the interior wall finishing yet there has been no detailed assessment of their fire performance.In this research work prototypes of low-density insulating boards for indoor spaces from hemp shives using carbamide resin binder and cold pressing were studied.Bench-scale cone calorimeter tests were conducted to evaluate fire risk,with a focus on assessing material flammability properties and the influence of PCM on the results.In this research,the amount of smoke,heat release rate,effective heat of combustion,specific extinction coefficient,mass loss,carbon dioxide yield,specific loss factor,ignition time of hemp straws samples and samples of hemp straws with 10%and without PCM admixture were compared.There is a risk of flammability for PCM and their fire reaction has not been evaluated when incorporating PCM into interior wall finishing boards.The obtained results can be used by designers to balance the potential energy savings of using PCM with a more complete understanding and predictability of the associated fire risk when using the proposed boards.It also allows for appropriate risk mitigation strategies. 展开更多
关键词 Encapsuled phase change material renewable resources reaction to fire FLAMMABILITY
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Anti-carbon deposition performance of twinned HZSM-5 encapsulated Ru in the toluene alkylation with methanol
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作者 Guixian Li Tao Tian +4 位作者 Hanxu Li Jinlian Li Tingna Shao Qi Zhang Peng Dong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第9期1-8,共8页
Toluene methylation with methanol to produce para-xylene has been extensively and intensively studied.However,the methanol-to-hydrocarbons(MTH)side reaction in this reaction is difficult to be inhibited,which will cau... Toluene methylation with methanol to produce para-xylene has been extensively and intensively studied.However,the methanol-to-hydrocarbons(MTH)side reaction in this reaction is difficult to be inhibited,which will cause a mass of carbon deposition and cover the catalyst surface,resulting in catalyst deactivation.Here,a dual-functional Ru@HZSM-5 catalyst with high para-selectivity and low carbon deposition was prepared by encapsulating Ru metal with HZSM-5.According to catalytic performance studies,the Ru@HZSM-5 catalyst produced xylene selectivity of 98%and para-xylene selectivity of 96%.Meanwhile,we find that carbon precursors(e.g.ethylene)were very little when Ru catalyst was used,but the results of HZSM-5 catalyst were completely opposite.Ru@HZSM-5 catalyst achieves a lower carbon deposition rate of only 6%of HZSM-5.The main possible reason for this is that the initial C-C bond between methanol and the olefin is difficult to form. 展开更多
关键词 Twinned HZSM-5 encapsulated metal Shape-selective catalysis Anti-carbon deposition
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Finned Zn-MFI zeolite encapsulated noble metal nanoparticle catalysts for the oxidative dehydrogenation of propane with carbon dioxide
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作者 En-Hui Yuan Yiming Niu +7 位作者 Xing Huang Meng Li Jun Bao Yong-Hong Song Bingsen Zhang Zhao-Tie Liu Marc-Georg Willinger Zhong-Wen Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期479-491,I0011,共14页
Oxidative dehydrogenation of propane with carbon dioxide(CO_(2)-ODP)characterizes the tandem dehydrogenation of propane to propylene with the reduction of the greenhouse gas of CO_(2)to valuable CO.However,the existin... Oxidative dehydrogenation of propane with carbon dioxide(CO_(2)-ODP)characterizes the tandem dehydrogenation of propane to propylene with the reduction of the greenhouse gas of CO_(2)to valuable CO.However,the existing catalyst is limited due to the poor activity and stability,which hinders its industrialization.Herein,we design the finned Zn-MFI zeolite encapsulated noble metal nanoparticles(NPs)as bifunctional catalysts(NPs@Zn-MFI)for CO_(2)-ODP.Characterization results reveal that the Zn2+species are coordinated with the MFI zeolite matrix as isolated cations and the NPs of Pt,Rh,or Rh Pt are highly dispersed in the zeolite crystals.The isolated Zn2+cations are very effective for activating the propane and the small NPs are favorable for activating the CO_(2),which synergistically promote the selective transformation of propane and CO_(2)to propylene and CO.As a result,the optimal 0.25%Rh0.50%Pt@Zn-MFI catalyst shows the best propylene yield,satisfactory CO_(2)conversion,and long-term stability.Moreover,considering the tunable synergetic effects between the isolated cations and NPs,the developed approach offers a general guideline to design more efficient CO_(2)-ODP catalysts,which is validated by the improved performance of the bifunctional catalysts via simply substituting Sn4+cations for Zn2+cations in the MFI zeolite matrix. 展开更多
关键词 Oxidative dehydrogenation PROPANE Carbon dioxide Finned Zn-MFI zeolite encapsulated noble metal nanoparticles
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Research Progress of Sunscreen Agents and Encapsulate Technology
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作者 Zheng Xiaoyang Meng Xiangjing +6 位作者 Li Min Liu Bo Zhang Xiangkui Duan Chong gang Zhang Daizhou Ling Peixue Wang Dongliang 《China Detergent & Cosmetics》 CAS 2023年第2期56-61,共6页
The harm of ultraviolet radiation to human skin and the mechanism of traditional sunscreen agents and natural sunscreen agents were reviewed.Sunscreen agents were usually encapsulated with delivery systems due to the ... The harm of ultraviolet radiation to human skin and the mechanism of traditional sunscreen agents and natural sunscreen agents were reviewed.Sunscreen agents were usually encapsulated with delivery systems due to the instability and skin permeability.The research progress of several common sunscreen delivery systems was introduced,the future research direction of sunscreen agents was also prospected. 展开更多
关键词 UV radiation SUNSCREEN encapsulate photo-protection
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Silicalite-1 zeolite encapsulated Fe nanocatalyst for Fenton-like degradation of methylene blue 被引量:1
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作者 Hongwei Guo Linyuan Chen +2 位作者 Xueying Zhang Huanhao Chen Yan Shao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第1期251-259,共9页
Encapsulation of Fe nanoparticles in zeolite is a promising way to significantly improve the catalytic activity and stability of Fe-based catalysts during the degradation process of organic pollutants.Herein,Fe nanoca... Encapsulation of Fe nanoparticles in zeolite is a promising way to significantly improve the catalytic activity and stability of Fe-based catalysts during the degradation process of organic pollutants.Herein,Fe nanocatalysts were encapsulated into silicalite-1(S-1)zeolite by using a ligand-protected method(with dicyandiamide(DCD)as a organic ligand)under direct hydrothermal synthesis condition.High-resolution transmission electron microscopy(HRTEM)results confirmed the high dispersion of Fe nanocatalysts which were successfully encapsulated within the voids among the primary particles of the S-1 zeolite.The developed S-1 zeolite encapsulated Fe nanocatalyst(Fe@S-1)exhibited significantly improved catalytic activity and reusability in the catalytic degradation process of methylene blue(MB).Specifically,the developed Fe0.021@S-1 catalyst showed high catalytic degradation activity,giving a high MB degradation efficiency of 100%in 30 min,outperformed the conventional impregnated catalyst(Fe/S-1).Moreover,the Fe@S-1 catalyst afforded an outstanding stability,showing only ca.7.9%activity loss after five cycling tests,while the Fe/S-1 catalyst presented a significantly activity loss of 50.9%after only three cycles.Notably,the encapsulation strategy enabled a relatively lower Fe loading in the Fe@S-1 catalyst in comparison with that of the Fe/S-1 catalyst,i.e.,0.35%vs.0.81%(mass).Radical scavenging experiments along with electron spin resonance(ESR)measurements confirmed that the major role ofOH in the MB degradation process.Specifically,Fe@S-1 catalyst with high molar ratio of[Fe(DCD)]Cl3 is beneficial to form Fe complexes/nanoclusters in the voids(which has large pore size of 1–2 nm)among the primary particles of the zeolite,and thus improving the diffusion and accessibility of reactants to Fe active sites,and thus exhibiting a relatively higher degradation efficiency.This work demonstrates that zeolite-encapsulated Fe nanocatalysts present potential applications in the advanced oxidation of wastewater treatment. 展开更多
关键词 ZEOLITE Encapsulation Fe nanocatalyst Degradation Methylene blue
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Effects of Encapsulated Enzyme and Yeast Products on in Vitro Rumen Fermentation
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作者 Zhang Mei-mei Liang Ge-ge +4 位作者 Chen Ming-ming Jin Long Xie Xiao-lai Zhang Yong-gen Jiao Pei-xin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2022年第2期28-37,共10页
Batch cultures of mixed rumen micro-organisms were conducted to evaluate the effects of encapsulated yeast(+EY)and encapsulated enzyme(+EE)using plant proteins(barley and oats grain)on rumen fermentation in vitro,inve... Batch cultures of mixed rumen micro-organisms were conducted to evaluate the effects of encapsulated yeast(+EY)and encapsulated enzyme(+EE)using plant proteins(barley and oats grain)on rumen fermentation in vitro,investigate the abilities of encapsulated yeast and encapsulated enzyme to prevent rumen digestion in vitro.Treatments of the study were the control,+EY,+EE products(3.33 mg·mL^(-1) of the incubation medium),unencapsulated yeast(-EY)and enzyme(-EE)products(0.17 and 0.17μL·mL^(-1) of the incubation medium,respectively).+EY group increased dry matter disappearance(DMD,P<0.01)and the total volatile fatty acids(TVFA,P<0.01)at 3 h of the incubation compared with the control,regardless of encapsulation of yeast.Gas production(GP)of+EY group was higher(P=0.05,29.94 mL·mL^(-1) organic matter,OM)than that of the control(25.08 mL·g^(-1) OM)at 3 h of the incubation.Supplementation+EY increased DMD(P=0.04,0.394 vs 0.352,respectively)and acetic proportion(P=0.04,52.6 vs 49.8 mol•100 mL^(-1),respectively)at 6 h of the incubation and increased A:P ratio(P<0.01,3.11 and 2.86,respectively)at 24 h of the incubation,as compared to unencapsulation of yeast.Supplementation of enzyme had higher(P≤0.04)GP,DMD and TVFA at 3 and 6 h of the incubation compared with the control,regardless of encapsulation.Moreover,the addition of+EE produced greater GP at 6(P<0.01,92.35 vs 78.21 mL·g^(-1) OM,respectively),12(218.47 vs 159.18 mL·g^(-1) OM)and 24 h(380.97 vs 297.78 mL·g^(-1) OM,respectively)of the incubation,higher DMD(0.347 vs 0.313,respectively)at 3 h of the incubation as compared to-EE group.The study showed that the encapsulation might protect part of yeast and enzyme from releasing to the rumen throughout the digestion in vitro,resulting in higher or no difference of rumen fermentation parameters compared with unencapsulated groups at any incubation times.In comparison with-EY and-EE,the higher rumen fermentation parameters at the early incubation time were observed,which could be attributed to the higher concentration of yeast or enzyme.However,regardless of the encapsulation,the results indicated that both yeast and enzyme only improved the speed rather than the extent of rumen fermentation in vitro. 展开更多
关键词 dry matter digestion encapsulated enzyme encapsulated yeast gas production in vitro volatile fatty acid
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Microstreaming velocity field and shear stress created by an oscillating encapsulated microbubble near a cell membrane 被引量:3
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作者 王莉 屠娟 +2 位作者 郭霞生 许迪 章东 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期270-276,共7页
Sonoporation mediated by microbubbles is being extensively studied as a promising technology to facilitate gene/drug delivery to cells. However, the theoretical study regarding the mechanisms involved in sonoporation ... Sonoporation mediated by microbubbles is being extensively studied as a promising technology to facilitate gene/drug delivery to cells. However, the theoretical study regarding the mechanisms involved in sonoporation is still in its infancy.Microstreaming generated by pulsating microbubble near the cell membrane is regarded as one of the most important mechanisms in the sonoporation process. Here, based on an encapsulated microbubble dynamic model with considering nonlinear rheological effects of both shell elasticity and viscosity, the microstreaming velocity field and shear stress generated by an oscillating microbubble near the cell membrane are theoretically simulated. Some factors that might affect the behaviors of microstreaming are thoroughly investigated, including the distance between the bubble center and cell membrane(d), shell elasticity(χ), and shell viscosity(κ). The results show that(i) the presence of cell membrane can result in asymmetric microstreaming velocity field, while the constrained effect of the membrane wall decays with increasing the bubble-cell distance;(ii) the bubble resonance frequency increases with the increase in d and χ, and the decrease in κ,although it is more dominated by the variation of shell elasticity; and(iii) the maximal microstreaming shear stress on the cell membrane increases rapidly with reducing the d, χ, and κ. The results suggest that microbubbles with softer and less viscous shell materials might be preferred to achieve more efficient sonoporation outcomes, and it is better to have bubbles located in the immediate vicinity of the cell membrane. 展开更多
关键词 microstreaming shear stress SONOPORATION encapsulated microbubbles
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Encapsulated islets transplantation: Past, present and future 被引量:4
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作者 Naoaki Sakata Shoichiro Sumi +3 位作者 Gumpei Yoshimatsu Masafumi Goto Shinichi Egawa Michiaki Unno 《World Journal of Gastrointestinal Pathophysiology》 CAS 2012年第1期19-26,共8页
Islet transplantation could become an ideal treatment for severe diabetes to prevent hypoglycemia shock and irreversible diabetic complications, once some of the major and unresolved obstacles are overcome, including ... Islet transplantation could become an ideal treatment for severe diabetes to prevent hypoglycemia shock and irreversible diabetic complications, once some of the major and unresolved obstacles are overcome, including limited donor supplies and side effects caused by permanent immunosuppressant use. Approximately 30 years ago, some groups succeeded in improving the blood glucose of diabetic animals by transplanting encapsulated islets with semi-permeable membranes consisting of polymer. A semi-permeable membrane protects both the inner islets from mechanical stress and the recipient’s immune system (both cellular and humoral immunities), while allowing bidirectional diffusion of nutrients, oxygen, glucose, hormones and wastes, i.e., immune-isolation. This device, which enables immune-isolation, is called encapsulated islets or bio-artificial pancreas. Encapsulation with a semipermeable membrane can provide some advantages: (1) this device protects transplanted cells from the recipient’s immunity even if the xenogeneic islets (from large animals such as pig) or insulin-producing cells are derived from cells that have the potential for differentiation (some kinds of stem cells). In other words, the encapsulation technique can resolve the problem of limited donor supplies; and (2) encapsulation can reduce or prevent chronic administration of immunosuppressants and, therefore, important side effects otherwise induced by immunosuppressants. And now, many novel encapsulated islet systems have been developed and are being prepared for testing in a clinical setting. 展开更多
关键词 ISLET TRANSPLANTATION encapsulateD ISLETS Bio-artificial PANCREAS
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High efficient catalytic oxidation of 5-hydroxymethylfurfural into 2,5-furandicarboxylic acid under benign conditions with nitrogen-doped graphene encapsulated Cu nanoparticles 被引量:3
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作者 Chaoxin Yang Xiao Li +7 位作者 Zhenzhou Zhang Bohan Lv Jiachun Li Zhenjian Liu Wanzhen Zhu Furong Tao Guangqiang Lv Yongxing Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第11期96-105,共10页
Selective oxidation of 5-hydroxymethylfurfual(HMF) to 2,5-furandicarboxylic acid(FDCA) as a bioplastics monomer is efficiently promoted by a simple system without noble-metal and base additives. In this work, graphene... Selective oxidation of 5-hydroxymethylfurfual(HMF) to 2,5-furandicarboxylic acid(FDCA) as a bioplastics monomer is efficiently promoted by a simple system without noble-metal and base additives. In this work, graphene oxide(GO) was first synthesised by an electrochemical method with flexible graphite paper(FGP) as start carbon material, then, nitrogen-doped graphene(NG) layers encapsulated Cu nanoparticles(NPs) was prepared by one-step thermal treatment of GO supported Cu2+ in flowing NH3 atmosphere. Compared with NG supported Cu NPs prepared by the traditional impregnation method, enhanced catalytic activity was achieved over Cu/NG and an FDCA yield of 95.2% was achieved under mild reaction conditions with tert-butylhydroperoxide(t-BuOOH) as the oxidant. Control experiments with different catalysts and different addition procedure of t-BuOOH showed the yield of HMF and various intermediates during reaction. From the changing of intermediates concentrations and reaction rates, a reaction pathway through HMF-DFF-FFCA-FDCA was proposed. This work gives a more convenient, more green,more economical and effective method in encapsulated metal NPs preparation and high selectivity in HMF oxidation to FDCA under mild conditions. 展开更多
关键词 Graphene oxide encapsulated nanoparticles 5-hydroxymethylfurfual 2 5-furandicarboxylic acid Oxidation Noble-metal free
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Experimental Study on Surface Dielectric Barrier Discharge Plasma Actuator with Different Encapsulated Electrode Widths for Airflow Control at Atmospheric Pressure 被引量:4
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作者 齐晓华 杨亮 +3 位作者 闫慧杰 金英 滑跃 任春生 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第10期1005-1011,共7页
The surface dielectric barrier discharge (SDBD) plasma actuator has shown great promise as an aerodynamic flow control device. In this paper, the encapsulated electrode width of a SDBD actuator is changed to study t... The surface dielectric barrier discharge (SDBD) plasma actuator has shown great promise as an aerodynamic flow control device. In this paper, the encapsulated electrode width of a SDBD actuator is changed to study the airflow acceleration behavior. The effects of encapsulated electrode width on the actuator performance are experimentally investigated by measuring the dielectric layer surface potential, time-averaged ionic wind velocity and thrust force. Experimental results show that the airflow velocity and thrust force increase with the encapsulated electrode width. The results can be attributed to the distinct plasma distribution at different encapsulated electrode widths. 展开更多
关键词 atmospheric pressure discharge plasma surface dielectric barrier discharge(SDBD) flow control encapsulated electrode width Schlieren visualization
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Conventional treatments and non-PEGylated liposome encapsulated doxorubicin for visceral leishmaniasis:A scoping review 被引量:2
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作者 Soumya Ranjan Satapathy Rudra Narayan Sahoo 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2022年第7期293-307,共15页
Visceral leishmaniasis(VL),also known as Kala-azar,is caused by Leishmania(L.)donovani complex,which includes L.donovani and L.infantum and is associated with a high death rate as compared to the cutaneous and subcuta... Visceral leishmaniasis(VL),also known as Kala-azar,is caused by Leishmania(L.)donovani complex,which includes L.donovani and L.infantum and is associated with a high death rate as compared to the cutaneous and subcutaneous form.Treatment of VL includes chemotherapeutic agents which are associated with some major hurdles like toxicities,parenteral administration,high cost,parasite resistance and stability.Hence,there is an urgent requirement to develop novel chemotherapeutic agents or repurposing of existing drugs against VL.Developing formulation of new chemical entity for the treatment of VL is laborious,time consuming and associated with huge financial burden.However,screening of existing chemotherapeutic agents is a good alternative to avail cost-effective treatment option for VL.Non-PEGylated liposome encapsulated doxorubicin(Myocet®)is proposed as an alternative treatment option for VL in this review article.Here,we covered the fundamental aspects of VL,loophole associated with available current treatment strategies and non-PEGylated liposome encapsulated doxorubicin as a novel alternative formulation for treating VL,as this liposomal delivery system of doxorubicin might passively target the intra-cellular regions of macrophage. 展开更多
关键词 Visceral leishmaniasis DOXORUBICIN Passive targeting REPOSITIONING Non-PEGylated liposome encapsulated doxorubicin RESISTANCE
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Studying the performance of fully encapsulated rock bolts with modified structural elements 被引量:2
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作者 Jianhang Chen Hongbao Zhao +2 位作者 Fulian He Junwen Zhang Kangming Tao 《International Journal of Coal Science & Technology》 EI CAS CSCD 2021年第1期64-76,共13页
Numerical simulation is a useful tool in investigating the loading performance of rock bolts.The cable structural elements(cableSELs)in FLAC3D are commonly adopted to simulate rock bolts to solve geotechnical issues.I... Numerical simulation is a useful tool in investigating the loading performance of rock bolts.The cable structural elements(cableSELs)in FLAC3D are commonly adopted to simulate rock bolts to solve geotechnical issues.In this study,the bonding performance of the interface between the rock bolt and the grout material was simulated with a two-stage shearing coupling model.Furthermore,the FISH language was used to incorporate this two-stage shear coupling model into FLAC3D to modify the current cableSELs.Comparison was performed between numerical and experimental results to confirm that the numerical approach can properly simulate the loading performance of rock bolts.Based on the modified cableSELs,the influence of the bolt diameter on the performance of rock bolts and the shear stress propagation along the interface between the bolt and the grout were studied.The simulation results indicated that the load transfer capacity of rock bolts rose with the rock bolt diameter apparently.With the bolt diameter increasing,the performance of the rock bolting system was likely to change from the ductile behaviour to the brittle behaviour.Moreover,after the rock bolt was loaded,the position where the maximum shear stress occurred was variable.Specifically,with the continuous loading,it shifted from the rock bolt loaded end to the other end. 展开更多
关键词 Fully encapsulated rock bolts Numerical simulation Structural elements Shear coupling model Interface shear strength
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Enhanced active site extraction from perovskite LaCoO_(3) using encapsulated PdO for efficient CO_(2) methanation 被引量:1
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作者 Kuncan Wang Wen Li +3 位作者 Junjie Huang Jiale Huang Guowu Zhan Qingbiao Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第2期9-19,I0001,共12页
The extraction of metallic nanoparticles from perovskite-type oxides(ABO_(3)) under mild reducing conditions is a novel way to prepare well-dispersed supported catalysts(B/AOd). Herein, we found that the encapsulated ... The extraction of metallic nanoparticles from perovskite-type oxides(ABO_(3)) under mild reducing conditions is a novel way to prepare well-dispersed supported catalysts(B/AOd). Herein, we found that the encapsulated PdO in perovskite LaCoO_3(PdO@LaCoO_3) could facilitate the phase transformation of the perovskite structure at a low temperature owing to both strong H2 spillover of Pd and intimate interaction between the encapsulated PdO and LaCoO_(3). The pure LaCoO_(3) without PdO was relatively inert to CO_(2) hydrogenation(CO_(2) conversion <4%). In contrast, PdO@LaCoO_(3) exhibited excellent CO_(2) methanation performance with 62.3% CO_(2) conversion and >99% CH4 selectivity. The characterization results demonstrated that the catalytically active Co2 C was in-situ formed by carburization of the extracted Co0 during CO_(2) methanation for the PdO@LaCoO_(3) sample. Whereas, the LaCoO_(3) with surface supported PdO(PdO/LaCoO_(3)) showed a weak interaction and remained a perovskite structure with few Co_(2)C active centers after the catalytic reaction, which was similar to the parent LaCoO_(3). Accordingly, the PdO/LaCoO_(3) showed an inferior catalytic performance with 31.8% CO_(2) conversion and 87.4% CH_(4) selectivity. Therefore, the designed encapsulation structure of PdO within perovskite is critical to extract metallic NPs from perovskite-type oxides, which has the potential to prepare other integrated nanocatalysts based on perovskite-type oxides. 展开更多
关键词 Perovskite reduction PdO nanoparticles encapsulated structure Supported catalyst CO_(2)methanation
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Microflow-induced shear stress on biomaterial wall by ultrasound-induced encapsulated microbubble oscillation 被引量:1
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作者 胡继文 钱盛友 +2 位作者 孙佳娜 吕云宾 胡苹 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第9期307-312,共6页
A model of an ultrasound-driven encapsulated microbubble(EMB) oscillation near biomaterial wall is presented and used for describing the microflow-induced shear stress on the wall by means of a numerical method. The... A model of an ultrasound-driven encapsulated microbubble(EMB) oscillation near biomaterial wall is presented and used for describing the microflow-induced shear stress on the wall by means of a numerical method. The characteristic of the model lies in the explicit treatment of different types of wall for the EMB responses. The simulation results show that the radius-time change trends obtained by our model are consistent with the existing models and experimental results. In addition, the effect of the elastic wall on the acoustic EMB response is stronger than that of the rigid wall, and the shear stress on the elastic wall is larger than that of the rigid wall. The closer the EMB to the wall, the greater the shear stress on the wall. The substantial shear stress on the wall surface occurs inside a circular zone with a radius about two-thirds of the bubble radius. This paper may be of interest in the study of potential damage mechanisms to the microvessel for drug and gene delivery due to sonoporation. 展开更多
关键词 encapsulated microbubble shear stress SONOPORATION
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Chemoselective Catalytic Hydrogenation of Nitroarenes Using MOF-Derived Graphitic Carbon Layers Encapsulated Ni Catalysts 被引量:1
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作者 Wu Genghuang Rong Junfeng 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2021年第3期40-49,共10页
Replacement of precious noble metal catalysts with cost-effective,non-noble heterogeneous catalysts for chemoselective hydrogenation of nitroarenes holds tremendous promise for the clean synthesis of nitrogen-containi... Replacement of precious noble metal catalysts with cost-effective,non-noble heterogeneous catalysts for chemoselective hydrogenation of nitroarenes holds tremendous promise for the clean synthesis of nitrogen-containing chemicals.Graphitic carbon layers encapsulated Ni catalysts(Ni@CN)are generated by a facile,scalable and straightforward strategy via the pyrolysis of 2,5-pyridinedicarboxylic acid coordinated Ni-MOF acting as the precursor.Physicochemical properties of the Ni@CN catalysts have been investigated by X-ray diffraction,scanning electron microscopy,transmission electron microscopy,elemental analysis and N2 adsorption-desorption analysis.The Ni@CN catalysts were found to be highly efficient in the chemoselective hydrogenation of various nitroarenes with other functional groups towards corresponding anilines under mild reaction conditions(85℃,1.0 MPa of H2 pressure).Based on the results of controlled tests,the catalytic activity can be attributed to the Ni NPs,while the presence of graphitic carbon layers favors the preferential adsorption of the nitro groups.The recyclability and anti-sulfur poisoning capability of Ni@CN were also investigated. 展开更多
关键词 chemoselective hydrogenation carbon encapsulated metal-organic frameworks nickel nanoparticles NITROARENES
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Characterization of carbon encapsulated Fe-nanoparticles prepared by confined arc plasma
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作者 魏智强 刘立刚 +2 位作者 杨华 张材荣 冯旺军 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第9期2026-2030,共5页
Carbon encapsulated Fe nanoparticles were successfully prepared via confined arc plasma method. The composition, morphology, microstructure, specific surface area and particle size of the product were characterized vi... Carbon encapsulated Fe nanoparticles were successfully prepared via confined arc plasma method. The composition, morphology, microstructure, specific surface area and particle size of the product were characterized via X-ray diffraction, transmission electron microscopy, high resolution transmission electron microscopy, energy dispersive X-ray spectrometry and Brunauer-Emmett-Teller N2 adsorption. The experiment results show that the carbon encapsulated Fe nanoparticles have clear core-shell structure. The core of the particles is body centered cubic Fe, and the shell is disorder carbons. The particles are in spherical or ellipsoidal shapes. The particle size of the nanocapsules ranges from 15 to 40 nm, with the average value of about 30 nm. The particle diameter of the core is 18 nm, the thickness of the shells is 6-8 nm, and the specific surface area is 24 m2/g. 展开更多
关键词 carbon encapsulation Fe nanoparticles confined arc plasma
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Phenol Biodegradation by <i>Corynebacterium glutamicum</i>Encapsulated in Electrospun Fibers 被引量:1
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作者 Alon Nardi Ron Avrahami +2 位作者 Eyal Zussman J. Stefan Rokem Charles L. Greenblatt 《Journal of Environmental Protection》 2012年第2期164-168,共5页
In Northern Israel, olive mills discharge liquid waste causing contamination of subterranean aquifers with phenol, rendering them albeit temporarily, unfit for both drinking and irrigation. The impact of groundwater p... In Northern Israel, olive mills discharge liquid waste causing contamination of subterranean aquifers with phenol, rendering them albeit temporarily, unfit for both drinking and irrigation. The impact of groundwater pollution due to phenol spillage can be extensive. We developed a model system for the biodegradation of phenol-contaminated wastewater by the bacterium Corynebacterium glutamicum. Experiments consisting of suspended cultures demonstrated the native ability of this organism to utilize phenol for its metabolic pathways enabling degradation, at levels of nearly 100 ppm within 24 hours. With the use of bioinformatic data, a complete degradation pathway was constructed. Quantitative Real Time PCR analysis of the first two enzymes in this pathway revealed very distinct expression patterns and two different regulation mechanisms were postulated. Additionally, an electrospinning core-shell system was used to assemble electrospun microtubes containing bacteria on porous metallic carriers. We used these carriers as a new immobilization technique and demonstrated their significant phenol degrading capacity in a batch bioreactor configuration. This system demonstrates the feasibility of constructing a water treatment system for the management of phenol-contaminated water. 展开更多
关键词 PHENOL Biodegradation encapsulateD Bacteria Electrospinning Microtubes PHENOL 2-Monooxygenase Catechol 1 2-Dioxygenase OLIVE MILL WASTE Treatment OLIVE MILL WASTE OMW
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A Novel Method for Synthesis of Homogeneous Carbon Encapsulated Fe Nanoparticles Based on Natural Biopolymer
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作者 安玉良 武小娟 +2 位作者 隋志明 袁霞 刘艳秋 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第S1期452-455,共4页
A novel and efficient route for preparing carbon encapsulated metal nanomaterials using staple biopolymer-starch as the carbon precursor was presented. Fe particles can be effectively encapsulated inside carbon shells... A novel and efficient route for preparing carbon encapsulated metal nanomaterials using staple biopolymer-starch as the carbon precursor was presented. Fe particles can be effectively encapsulated inside carbon shells by carbonizing composite of starch and iron oxide under hydrogen in a controllable way. Transmission electron microscopy (TEM), energy dispersive X-ray (EDX) and X-ray diffraction (XRD) were employed to characterize carbon encapsulated nanomaterials. The α-Fe and γ-Fe phases were clearly identified in those carbon encapsulated nanoparticles. The growth mechanism of carbon encapsulated metal nanoparticles was briefly discussed. 展开更多
关键词 carbon encapsulated nanoparticles preparation metal STARCH rare earths
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Finite element modeling of acoustic scattering from an encapsulated microbubble near rigid boundary
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作者 黄蓓 张艳丽 +1 位作者 章东 龚秀芬 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第5期378-383,共6页
This article proposes a finite element model (FEM) for predicting the acoustic scattering from an encapsulated microbubble near rigid boundary. The validity of the model is first examined by comparing the acoustic n... This article proposes a finite element model (FEM) for predicting the acoustic scattering from an encapsulated microbubble near rigid boundary. The validity of the model is first examined by comparing the acoustic nonlinear response of a free microbubble with that obtained by the Church model. Then this model is used to investigate the effect of the rigid boundary on acoustic scattering signals from microbubble. The results indicate that the resonance frequency decreases while the oscillation amplitude increases as the microbubble approaches the rigid boundary. In addition, the fundamental component of the acoustic scattering signal is enhanced compared with that of the free microbubble. 展开更多
关键词 bound encapsulated microbubble acoustic scattering finite element model
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Characteristics and Microstructure of Graphite Encapsulated Iron Nanoparticles
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作者 曹宏 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2007年第2期214-217,共4页
The graphite encapsulated a-Fe particles were prepared by reduction of stage-2 and stage-3 FeCI3 graphite intercalation compounds (GICs) with metallic potassium, X-ray diffraction analysis (XRD), energy dispersive... The graphite encapsulated a-Fe particles were prepared by reduction of stage-2 and stage-3 FeCI3 graphite intercalation compounds (GICs) with metallic potassium, X-ray diffraction analysis (XRD), energy dispersive X-ray spectroscopy (EDS) investigation and transmission electron microscopy (TEM) observation show that the reduction products of stage-2 FeCl3-GICs contains more abundant a-Fe nanoparticles than those of stage-3. High-resolution TEM (HRTEM) observation reveals that the nanoparticle of a-Fe was polycrystals or twins, which was real or quasi two-dimension in shape, and whose space orientation was strictly controlled by the graphene. Based on the experiment results, a possible growth model of the graphite encapsulated ct-Fe was proposed. 展开更多
关键词 encapsulated nanoparticle graphite intercalation compounds iron electron transmissionmicroscopy (TEM) TEMPLATE
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