The prevalence of iron deficiency anemia(IDA)remains high in infants,resulting in growth retardation,neurodevelopmental impairment,immunodeficiency and other irreversible injuries.Efficient and safe iron supplementati...The prevalence of iron deficiency anemia(IDA)remains high in infants,resulting in growth retardation,neurodevelopmental impairment,immunodeficiency and other irreversible injuries.Efficient and safe iron supplementation for infants has been the goal of recent research.This study aims to investigate the effect of encapsulated ferric pyrophosphate(FePP)on intestinal inflammation and gut microbiota in IDA suckling rats.Newborn Sprague-Dawley rats were gavaged with low and high doses of FePP and FeSO4(2 and 10 mg Fe/kg BW,respectively)during postnatal days 2-14,while the Ctrl group was gavaged with saline.Results showed that FePP supplementation was as effective as FeSO4 in promoting growth,alleviating anemia and restoring body iron levels.Both low and high doses of FePP could significantly down-regulate the expression of pro inflammatory cytokines in the colon to the level similar to that in the Ctrl group(P>0.05).However,the high dose of FeSO4 did not show a down-regulation effect.Compared with the Ctrl group,IDA caused a disturbance of gut microbiota composition in suckling rats,and FePP could restore this dysbiosis.Besides,FePP was more beneficial than FeSO4 in increasing the abundance of beneficial bacteria such as Bacteroides and Akkermansia.Spearman’s correlation analysis showed a correlation between gut microbiota and biochemical indicators such as iron status,pro-inflammatory cytokine expression,and oxidative stress level.Overall,these findings suggested that FePP could effectively improve IDA,and is more effective than FeSO4 in alleviating intestinal inflammation and regulating gut microbiota,which provides a basis for the application of new iron fortificant in infant formula.展开更多
The development of high-performance transition metal sulfide(TMS)/carbon composites to replace conventional graphite anode remains a critical challenge for advancing lithium-ion batteries(LIBs).In this study,a facile ...The development of high-performance transition metal sulfide(TMS)/carbon composites to replace conventional graphite anode remains a critical challenge for advancing lithium-ion batteries(LIBs).In this study,a facile self-sacrifice template method is developed to prepare FeS encapsulated into N,S co-doped carbon(FeS/NSC)composite using melamine-cyanuric acid(MCA)supermolecule as a multifunctional template precursor.The function of MCA supermolecule for material synthesis is explored,revealing its special function as a dispersant,dopant and pore-forming agent.Furthermore,the effect of Fe source dosage on the morphology,structure and composition of the final products is explored.The resultant FeS/NSC-0.1(where 0.1 represents the mass of added Fe source)exhibits the most optimal proportion,characterized by a good dispersion status of FeS within the NSC matrix,effective N,S co-doping and ample porosity.Benefiting from these merits,the FeS/NSC-0.1 anode demonstrates significantly improved cycling stability and rate capability when compared to the counterparts.Undoubtedly,this work offers a universal method to produce advanced transition metal sulfide/carbon composite electrodes for energy storage and conversion systems.展开更多
High-temperature phase change materials(PCMs)have attracted significant attention in the field of thermal energy storage due to their ability to store and release large amounts of heat within a small temperature fluct...High-temperature phase change materials(PCMs)have attracted significant attention in the field of thermal energy storage due to their ability to store and release large amounts of heat within a small temperature fluctuation range.However,their practical application is limited due to problems such as leakage,corrosion,and volume changes at high temperatures.Recent research has shown that macroencapsulation technology holds promise in addressing these issues.This paper focuses on the macroencapsulation technology of high-temperature PCMs,starting with a review of the classification and development history of high-temperature macroencapsulatd PCMs.Four major encapsulation strategies,including electroplating method,solid/liquid filling method,sacrificial material method,and powder compaction into sphere method,are then summarized.The methods for effectively addressing issues such as corrosion,leakage,supercooling,and phase separation in PCMs are analyzed,along with approaches for improving the heat transfer performance,mechanical strength,and thermal cycling stability of macrocapsules.Subsequently,the structure and packing arrangement optimization of macrocapsules in thermal storage systems is discussed in detail.Finally,after comparing the performance of various encapsulation strategies and summarizing existing issues,the current technical challenges,improvement methods,and future development directions are proposed.More attention should be given to utilizing AI technology and reinforcement learning to reveal the multiphysics-coupled heat and mass transfer mechanisms in macrocapsule applications,as well as to optimize material selection and encapsulation parameters,thereby enhancing the overall efficiency of thermal storage systems.展开更多
Herein,nanosized Hf_(6)Ta_(2)O_(17) encapsulated graphite flakes were firstly constructed using the sol-gel method,then deposited on the surface of carbon/carbon(C/C)composites by plasma spraying technique to prolong ...Herein,nanosized Hf_(6)Ta_(2)O_(17) encapsulated graphite flakes were firstly constructed using the sol-gel method,then deposited on the surface of carbon/carbon(C/C)composites by plasma spraying technique to prolong their service span in critical environments.Nanoindentation results affirmed the active influ-ence of graphite flakes on elevating the toughness of the Hf_(6)Ta_(2)O_(17) coating.Besides,after being exposed to the oxyacetylene torch with a peak temperature of about 2000℃,the sample achieved near zero ab-lation(0.06 mg/s),meanwhile its porosity and mass ablation rate showed 39.5%and 60.0%reduction when compared to pure Hf_(6)Ta_(2)O_(17) sample.During exposure,the external Hf_(6)Ta_(2)O_(17) served as an oxy-gen barrier for internal graphite flakes,inversely internal graphite flakes provided a“pinning”effect on external Hf_(6)Ta_(2)O_(17),which accounted for its exceptional ablation performance.This work offers a new insight into the design of surface modification of C/C composites and other high-temperature structural materials.展开更多
Non-alcoholic fatty liver disease(NAFLD)is prevalent worldwide as a chronic liver disease that not only gives rise to hepatic complications,but leads to other chronic diseases such as type 2 diabetes and atheroscleros...Non-alcoholic fatty liver disease(NAFLD)is prevalent worldwide as a chronic liver disease that not only gives rise to hepatic complications,but leads to other chronic diseases such as type 2 diabetes and atherosclerosis.The aberrant accumulation of lipid droplets(LDs)in hepatocytes is a prominent signature of NAFLD.However,conventional techniques lack the capability to effectively monitor the dynamic changes in LD levels during NAFLD with living organisms.Hence,it is imperative to develop LD-specific long-wavelength fluorescent probes with high imaging contrast for the in-situ diagnosis of NAFLD.In this study,we synthesized a new LD-selective long-wavelength fluorescent probe,denoted as LD-1,based on the twisted intramolecular charge transfer(TICT)mechanism.The probe exhibits a large Stokes shift and intensive fluorescence emission in nonpolar and viscous solutions.By self-assembling LD-1 with bovine serum albumin(BSA),a biocompatible,long-wavelength fluorescent probe hybrid,LD-1@BSA,was formed,allowing for LDs to be selectively imaged in hepatocytes.Moreover,LD-1@BSA successfully discriminates NAFLD cells before and after drug treatment,and achieves non-invasive and real-time monitoring of LD accumulation in a mouse model of NAFLD.展开更多
Over the past decade,electrocatalytic reduction of CO_(2)has gained substantial attention.However,hardly any of the previous reviews have focused on the systematic discussion of polymer-molecular catalyst composites a...Over the past decade,electrocatalytic reduction of CO_(2)has gained substantial attention.However,hardly any of the previous reviews have focused on the systematic discussion of polymer-molecular catalyst composites as an emerging system for the electrochemical transformation of CO_(2)to value-added products.In this review,we first give a brief overview of the general features of solid-state and molecular catalysts,and then advance the discussion to polymer-catalyst composite systems,with particular emphasis on polymer-encapsulated molecular catalysts,where the coordination environment surrounding molecular catalysts can be modified via polymer encapsulation to promote the overall performance of CO_(2)electrocatalysis.The elucidation of the possible reaction mechanisms of this emerging electrocat-alytic system along with proposed optimization strategies is also summarized and discussed based on recently published reports,followed by the challenges and prospects of their industrial applications at the end of this review.From this review,we hope the audience can gain a comprehensive understanding of the electrocatalytic mechanism of the coordinating polymers and valuable insights into engineering the microenvironment surrounding the metal complexes for potential future research directions.展开更多
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
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
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
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
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
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
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
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
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
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
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
In the present research,enzyme encapsulated hydrogels(single gels and double network gels)and enzyme immobilized magnetic beads,which allow high-throughput screening,were fabricated and evaluated in terms of the pre...In the present research,enzyme encapsulated hydrogels(single gels and double network gels)and enzyme immobilized magnetic beads,which allow high-throughput screening,were fabricated and evaluated in terms of the preservation,precision, and repeatability of enzyme activity.The fabricated gels and magnetic beads were analyzed in a 96-well microassay plate.Trypsin was successfully encapsulated in both types of gels and immobilized to the magnetic beads.However,pepsin,either encapsulated in the gels or immobilized to the magnetic beads,could not react with its substrates.The adaptability to various enzymes (e.g.,trypsin,β-glucuronidase,and CYP1A1)in the single gels and magnetic beads was superior to that in double network gels.However,the soak out of the enzymes was observed in the single gels.The double network gels could encapsulate trypsin,whereas the fabrication of the other enzymes(e.g.β-glucuronidase,CYP1A1,and pepsin)failed because of the inactivation of the enzymes by acryl amide and ammonium peroxodisulfate,which are the components of the gel formulation. The enzyme reaction in the magnetic beads exhibited the highest efficiency among the three fabrication methods.Furthermore, the stability of the enzymes immobilized to the magnetic beads was better than that fabricated by the other methods,and the activities of trypsin andβ-glucuronidase did not decline for up to one week.In addition,in the magnetic beads,the activities of trypsin andβ-glucuronidase can be well repeated.Hence,although the adaptability of the double network gels to various enzymes is currently limited,the efficiency of the enzyme encapsulation can be improved by optimizing the formulation of acryl amide gels.展开更多
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
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
基金funded by the National Natural Science Foundation of China(32001676)the Young Elite Scientists Sponsorship Program by China Association for Science and Technology(CAST)(2022QNRC001).
文摘The prevalence of iron deficiency anemia(IDA)remains high in infants,resulting in growth retardation,neurodevelopmental impairment,immunodeficiency and other irreversible injuries.Efficient and safe iron supplementation for infants has been the goal of recent research.This study aims to investigate the effect of encapsulated ferric pyrophosphate(FePP)on intestinal inflammation and gut microbiota in IDA suckling rats.Newborn Sprague-Dawley rats were gavaged with low and high doses of FePP and FeSO4(2 and 10 mg Fe/kg BW,respectively)during postnatal days 2-14,while the Ctrl group was gavaged with saline.Results showed that FePP supplementation was as effective as FeSO4 in promoting growth,alleviating anemia and restoring body iron levels.Both low and high doses of FePP could significantly down-regulate the expression of pro inflammatory cytokines in the colon to the level similar to that in the Ctrl group(P>0.05).However,the high dose of FeSO4 did not show a down-regulation effect.Compared with the Ctrl group,IDA caused a disturbance of gut microbiota composition in suckling rats,and FePP could restore this dysbiosis.Besides,FePP was more beneficial than FeSO4 in increasing the abundance of beneficial bacteria such as Bacteroides and Akkermansia.Spearman’s correlation analysis showed a correlation between gut microbiota and biochemical indicators such as iron status,pro-inflammatory cytokine expression,and oxidative stress level.Overall,these findings suggested that FePP could effectively improve IDA,and is more effective than FeSO4 in alleviating intestinal inflammation and regulating gut microbiota,which provides a basis for the application of new iron fortificant in infant formula.
基金supported by the Science Technology Talents Lifting Project of Hunan Province(No.2022TJ-N16)the Natural Science Foundation of Hunan Province(Nos.2024JJ4022,2023JJ30277,2025JJ60382)+3 种基金the China Postdoctoral Fellowship Program(GZC20233205)the Scientifc Research Fund of Hunan Provincial Education Department,China(No.24B0270)the National Natural Science Foundation of China(No.32201646)the Key Project of Jiangxi Provincial Research and Development Program(No.20243BBI91001).
文摘The development of high-performance transition metal sulfide(TMS)/carbon composites to replace conventional graphite anode remains a critical challenge for advancing lithium-ion batteries(LIBs).In this study,a facile self-sacrifice template method is developed to prepare FeS encapsulated into N,S co-doped carbon(FeS/NSC)composite using melamine-cyanuric acid(MCA)supermolecule as a multifunctional template precursor.The function of MCA supermolecule for material synthesis is explored,revealing its special function as a dispersant,dopant and pore-forming agent.Furthermore,the effect of Fe source dosage on the morphology,structure and composition of the final products is explored.The resultant FeS/NSC-0.1(where 0.1 represents the mass of added Fe source)exhibits the most optimal proportion,characterized by a good dispersion status of FeS within the NSC matrix,effective N,S co-doping and ample porosity.Benefiting from these merits,the FeS/NSC-0.1 anode demonstrates significantly improved cycling stability and rate capability when compared to the counterparts.Undoubtedly,this work offers a universal method to produce advanced transition metal sulfide/carbon composite electrodes for energy storage and conversion systems.
基金supported by the National Natural Science Foundation of China(Grant No.51976092)。
文摘High-temperature phase change materials(PCMs)have attracted significant attention in the field of thermal energy storage due to their ability to store and release large amounts of heat within a small temperature fluctuation range.However,their practical application is limited due to problems such as leakage,corrosion,and volume changes at high temperatures.Recent research has shown that macroencapsulation technology holds promise in addressing these issues.This paper focuses on the macroencapsulation technology of high-temperature PCMs,starting with a review of the classification and development history of high-temperature macroencapsulatd PCMs.Four major encapsulation strategies,including electroplating method,solid/liquid filling method,sacrificial material method,and powder compaction into sphere method,are then summarized.The methods for effectively addressing issues such as corrosion,leakage,supercooling,and phase separation in PCMs are analyzed,along with approaches for improving the heat transfer performance,mechanical strength,and thermal cycling stability of macrocapsules.Subsequently,the structure and packing arrangement optimization of macrocapsules in thermal storage systems is discussed in detail.Finally,after comparing the performance of various encapsulation strategies and summarizing existing issues,the current technical challenges,improvement methods,and future development directions are proposed.More attention should be given to utilizing AI technology and reinforcement learning to reveal the multiphysics-coupled heat and mass transfer mechanisms in macrocapsule applications,as well as to optimize material selection and encapsulation parameters,thereby enhancing the overall efficiency of thermal storage systems.
基金supported by the Innovation Foundation for Doctor Dissertation of Northwestern Polytechnical University(Grant No.CX2021006)the National Natural Science Foundation of China(Grant Nos.91860203,51727804,and 52130205)the Fundamental Research Funds for the Central Universities(Grant No.3102019TS0409).
文摘Herein,nanosized Hf_(6)Ta_(2)O_(17) encapsulated graphite flakes were firstly constructed using the sol-gel method,then deposited on the surface of carbon/carbon(C/C)composites by plasma spraying technique to prolong their service span in critical environments.Nanoindentation results affirmed the active influ-ence of graphite flakes on elevating the toughness of the Hf_(6)Ta_(2)O_(17) coating.Besides,after being exposed to the oxyacetylene torch with a peak temperature of about 2000℃,the sample achieved near zero ab-lation(0.06 mg/s),meanwhile its porosity and mass ablation rate showed 39.5%and 60.0%reduction when compared to pure Hf_(6)Ta_(2)O_(17) sample.During exposure,the external Hf_(6)Ta_(2)O_(17) served as an oxy-gen barrier for internal graphite flakes,inversely internal graphite flakes provided a“pinning”effect on external Hf_(6)Ta_(2)O_(17),which accounted for its exceptional ablation performance.This work offers a new insight into the design of surface modification of C/C composites and other high-temperature structural materials.
基金National Natural Science Foundation of China(Nos.22107029,22377135,22305178,92253306 and 82130099)the Taishan Scholars Program(No.tsqn202312305)+7 种基金the Young Elite Scientists Sponsorship Program by Chinese Chemical Societythe Fundamental Research Projects of Science&Technology Innovation and development Plan in Yantai City(No.2023JCYJ059)the Shandong Laboratory Program(No.SYS202205)the Fundamental Research Funds for the Central Universities(No.222201717003)the Programme of Introducing Talents of Discipline to Universities(No.B16017)the Open Funding Project of the State Key Laboratory of Bioreactor Engineeringthe State Key Laboratory of Drug Research(No.SKLDR-2023-KF-10)the Ministry of Education Key Laboratory on signaling Regulation and Targeting Therapy of Liver Cancer(Naval Medical University)(No.2023-MEKLLCMS/ZD-00*)。
文摘Non-alcoholic fatty liver disease(NAFLD)is prevalent worldwide as a chronic liver disease that not only gives rise to hepatic complications,but leads to other chronic diseases such as type 2 diabetes and atherosclerosis.The aberrant accumulation of lipid droplets(LDs)in hepatocytes is a prominent signature of NAFLD.However,conventional techniques lack the capability to effectively monitor the dynamic changes in LD levels during NAFLD with living organisms.Hence,it is imperative to develop LD-specific long-wavelength fluorescent probes with high imaging contrast for the in-situ diagnosis of NAFLD.In this study,we synthesized a new LD-selective long-wavelength fluorescent probe,denoted as LD-1,based on the twisted intramolecular charge transfer(TICT)mechanism.The probe exhibits a large Stokes shift and intensive fluorescence emission in nonpolar and viscous solutions.By self-assembling LD-1 with bovine serum albumin(BSA),a biocompatible,long-wavelength fluorescent probe hybrid,LD-1@BSA,was formed,allowing for LDs to be selectively imaged in hepatocytes.Moreover,LD-1@BSA successfully discriminates NAFLD cells before and after drug treatment,and achieves non-invasive and real-time monitoring of LD accumulation in a mouse model of NAFLD.
基金supported by the National Energy R&D Center of Petroleum Refining Technology(RIPP,SINOPEC)the National Key R&D Program of China(Nos.2021YFE0191200 and 2022YFA1504200).
文摘Over the past decade,electrocatalytic reduction of CO_(2)has gained substantial attention.However,hardly any of the previous reviews have focused on the systematic discussion of polymer-molecular catalyst composites as an emerging system for the electrochemical transformation of CO_(2)to value-added products.In this review,we first give a brief overview of the general features of solid-state and molecular catalysts,and then advance the discussion to polymer-catalyst composite systems,with particular emphasis on polymer-encapsulated molecular catalysts,where the coordination environment surrounding molecular catalysts can be modified via polymer encapsulation to promote the overall performance of CO_(2)electrocatalysis.The elucidation of the possible reaction mechanisms of this emerging electrocat-alytic system along with proposed optimization strategies is also summarized and discussed based on recently published reports,followed by the challenges and prospects of their industrial applications at the end of this review.From this review,we hope the audience can gain a comprehensive understanding of the electrocatalytic mechanism of the coordinating polymers and valuable insights into engineering the microenvironment surrounding the metal complexes for potential future research directions.
基金supported by the European Regional Development Fund Postdoctoral Research Support“Structures and Technology Development of Smart Insulation Materials for Indoor Microclimate Regulation”1.1.1.2/VIAA/1/16/152the European Social Fund within the Project“Development of the Academic Personnel of Riga Technical University in the Strategic Fields of Specialization”Nr.8.2.2.0/18/A/017.
文摘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.
基金Supported by the Special Fund for Agro-scientific Research in the Public Interest(201503134)。
文摘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.
基金the National Natural Science Foundation of China(NNSFC)(21805145&U1610108)the Department of Science and Technology of Shandong Province(ZR2019BB068)+2 种基金the Department of Science and Technology of Shanxi Province(201705D211001)Scientific and Technological Innovation Programs of High Education Institutions in Shanxi(201802001-1)the Department of Human Resource and Social Security of Shanxi Province(Y6SW9613B1)。
文摘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.
基金supported by National Natural Science Foundation of China(No.11175037)National Natural Science Foundation for Young Scientists of China(No.11305017)Special Fund for Theoretical Physics(No.11247239)
文摘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.
基金Projects supported by the National Basic Research Program,China(Grant No.2011CB707900)the National Natural Science Foundation of China(Grant Nos.81127901,81227004,81271589,11374155,11161120324,11074123,11174141,11274170,11104140,11474001,and 11474161)+1 种基金the National High Tech Research and Development Program,China(Grant No.2012AA022702)the Program for New Century Excellent Talents in University of Ministry of Education of China(Grant No.NCET-11-0236)
文摘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.
基金Supported by Research Seeds Quest Program in Japan Science and Technology Agency (NS)the Uehara Memorial Foundation (NS)Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports Science and Technology of Japan, B: 22390253 (SE), C: 22591513 (NS)
文摘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.
文摘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.
基金This paper was funded by the following:National Natural Science Foundation of China(51974317,51904302,52034009)Yue Qi Distinguished Scholar Project(800015Z1179,800015Z1138)China University of Mining and Technology(Beijing)and the Fundamental Research Funds for the Central Universities(2020YQNY06).
文摘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.
基金supported by the National Natural Science Foundation of China (Nos. 21536010 and 41673088)。
文摘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.
基金supported by the National Natural Science Foundation of China(21902097,21636006 and 21761132025)the China Postdoctoral Science Foundation(2019M653861XB)+1 种基金the Natural Science Foundation of Shaanxi Province(2020JQ-409)the Fundamental Research Funds for the Central Universities(GK201901001 and GK202003035)。
文摘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.
基金Projects supported by the National Natural Science Foundation of China(Grant Nos.11174077 and 11474090)the Natural Science Foundation of Hunan Province,China(Grant No.13JJ3076)+1 种基金the Science Research Program of Education Department of Hunan Province,China(Grant No.14A127)the Doctoral Fund of University of South China(Grant No.2011XQD46)
文摘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.
基金The Global COE Program from the Ministry of Education,Science,Sports,and Culture of Japan.
文摘In the present research,enzyme encapsulated hydrogels(single gels and double network gels)and enzyme immobilized magnetic beads,which allow high-throughput screening,were fabricated and evaluated in terms of the preservation,precision, and repeatability of enzyme activity.The fabricated gels and magnetic beads were analyzed in a 96-well microassay plate.Trypsin was successfully encapsulated in both types of gels and immobilized to the magnetic beads.However,pepsin,either encapsulated in the gels or immobilized to the magnetic beads,could not react with its substrates.The adaptability to various enzymes (e.g.,trypsin,β-glucuronidase,and CYP1A1)in the single gels and magnetic beads was superior to that in double network gels.However,the soak out of the enzymes was observed in the single gels.The double network gels could encapsulate trypsin,whereas the fabrication of the other enzymes(e.g.β-glucuronidase,CYP1A1,and pepsin)failed because of the inactivation of the enzymes by acryl amide and ammonium peroxodisulfate,which are the components of the gel formulation. The enzyme reaction in the magnetic beads exhibited the highest efficiency among the three fabrication methods.Furthermore, the stability of the enzymes immobilized to the magnetic beads was better than that fabricated by the other methods,and the activities of trypsin andβ-glucuronidase did not decline for up to one week.In addition,in the magnetic beads,the activities of trypsin andβ-glucuronidase can be well repeated.Hence,although the adaptability of the double network gels to various enzymes is currently limited,the efficiency of the enzyme encapsulation can be improved by optimizing the formulation of acryl amide gels.
基金This work was financially supported by the China Petroleum&Chemical Corporation(SINOPEC 420043-4,420043-10)。
文摘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.
文摘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.