Since the discovery of ZSM-5 molecular sieves as a promising catalyst material, the synthesis of ZSM-5 has been investigated in great detail. In the first synthesis of ZSM-5,tetrapropylammonium(TPA) was used as the te...Since the discovery of ZSM-5 molecular sieves as a promising catalyst material, the synthesis of ZSM-5 has been investigated in great detail. In the first synthesis of ZSM-5,tetrapropylammonium(TPA) was used as the templating agent. However, the industrial manufacture and application of ZSM-5 molecular sieves arc limited because TPA, the templating agent, is expensive. In the attempt to search for a suitable substitute for TPA,展开更多
AIM: To investigate the correlation between preoperative measurement in total knee arthroplasty and the prosthetic size implanted. METHODS: A prospective double-blind study of 50 arthroplasties was performed. Firstly,...AIM: To investigate the correlation between preoperative measurement in total knee arthroplasty and the prosthetic size implanted. METHODS: A prospective double-blind study of 50 arthroplasties was performed. Firstly, the reliability and correspondence between the size of said measurement and the actual implant utilized was determined. Secondly, the existing correlation between the intra- and interobserver determinations with the intraclass correlation coefficient was analyzed. RESULTS: An overall correspondence of 54%, improving up to 92% when the measured size admitted a difference of one size, was found. Good intra- and interobserver reliability with an intraclass correlation coefficient greater than 0.90(P < 0.001) was also discovered. CONCLUSION: Agreement between the preoperative measurement with standardized acetate templates and the prosthetic size implanted can be considered satisfactory. We thus conclude it is a reproducible technique.展开更多
Ceria nanotubes with high CO conversion activity by means of carbon nanotubes as removable templates in the simple liquid phase process were fabricated under moderate conditions. The pristine CNTs were first pretreate...Ceria nanotubes with high CO conversion activity by means of carbon nanotubes as removable templates in the simple liquid phase process were fabricated under moderate conditions. The pristine CNTs were first pretreated by refluxing in a 30% nitric acid solution at 140 ℃ for 24 h, then dispersed in an ethanolic Ce（NO3）3.6H2O solution with ultrasonic radiation at room temperature for 1 h. Under vigorous stirring, NaOH solution was added drop by drop into the above ethanolic solution until the pH value was 10. The product was collected and repeatedly washed with ethanol and on drying at 60 ℃, the CeO2/CNT composites were obtained. Then, the as-prepared composites were heated at 450 ℃ in an air atmosphere for 30 min to remove CNTs. The ceria nanotubes were characterized by X-Ray Diffraction （XRD）, Transmission Electron Microscopy （TEM）, and X-Ray Photoelectron Spectrum （XPS）. The results showed that the ceria nanotubes were polycrystalline face-centered cubic phase and were composed of lots of dense cefia nanoparficles. The diameter of cefia nanotubes was about 40-50 nm. Catalytic activity of the product for CO oxidation was carded out at the region of 30-300 ℃ in a U-shaped quartz reactor with feeding about 0.15 g of the catalyst, which was loaded on Al2O3 carder. The inlet gas composition was 1.0% CO and 28% O2 with N2 as balance, and the rate of flow was kept at 40 ml/min. The catalytic products were analyzed by gas chromatography. The as-repared CeO2 nanotubes showed higher CO oxidation activity, which indicated that the morphology of ceria products affected the catalytic performance. The ceria nanotubes supported on Al2O3 demonstrated that conversion temperature for CO oxidation to CO2 was lower than that for bulk catalysts.展开更多
AIM To analyze planning total hip arthroplasty(THA) with an additional anteroposterior hip view may increases the accuracy of preoperative planning in THA.METHODS We conducted prospective digital planning in 100 conse...AIM To analyze planning total hip arthroplasty(THA) with an additional anteroposterior hip view may increases the accuracy of preoperative planning in THA.METHODS We conducted prospective digital planning in 100 consecutive patients: 50 of these procedures were planned using pelvic overview only(first group), and the other 50 procedures were planned using pelvic overview plus antero-posterior(a.p.) hip view(second group). The planning and the procedure of each patient were performed exclusively by the senior surgeon. Fifty procedures with retrospective analogues planning were used as the control group(group zero). After the procedure, the planning was compared with the eventually implanted components(cup and stem). For statistic analysis the x^2 test was used for nominal variables and the t test was used for a comparison of continuous variables.RESULTS Preoperative planning with an additional a.p. hip view(second group) significantly increased the exact component correlation when compared to pelvic overview only(first group) for both the acetabular cup and the femoral stem(76% cup and 66% stem vs 54% cup and 32% stem). When considering planning ± 1 size, the accuracy in the second group was 96%(48 of 50 patients) for the cup and 94% for the stem(47 of 50patients). In the analogue control group(group zero), an exact correlation was observed in only 1/3 of the cases.CONCLUSION Digital THA planning performed by the operating surgeon and based on additional a.p. hip view significantly increases the correlation between preoperative planning and eventual implant sizes.展开更多
Objective To introduce a simple preoperative digital templating in uncemented total hip arthroplasty(THA) and to determine its accuracy for preoperative size selection of the prostheses.Methods A prospective study of ...Objective To introduce a simple preoperative digital templating in uncemented total hip arthroplasty(THA) and to determine its accuracy for preoperative size selection of the prostheses.Methods A prospective study of digital planned THAs was performed on 90 hips with different types of prostheses from August 2013 to Angust 2014.The plastic templates of different types of prostheses were scanned for desired digital templating and the scanned images were then processed to the transparent,digital templates using Photoshop software.We calibrated the scales of the digital templates with the preoperative radiographs,and then selected the right size of the component.The preoperatively digital planned component sizes were compared to the actual sizes used in the operation,as well as the preoperatively traditional planned sizes.Results In either cup or stem templating,no difference was found among the groups with different types of prostheses,and the accuracy of digital templating was statistically higher than traditional templating.In cup templating,digital planned and implanted cup sizes were identical in 43.33% of the cases,78.89% of the cup sizes were predicted within 1 size(± 2mm) and 95.56% were predicted within 2 sizes(±4 mm),all significantly higher than the results of traditional planned sizes(30.00%,P=0.044;61.11%,P=0.007;82.22%,P=0.004).The exact femoral stem size was predicted in 40.00% of cases using the digital templating,84.44% of stem sizes were predicted within 1 size,and 93.33% within 2 sizes,better than using traditional templating(25.56%,P=0.028;53.33%,P<0.001;77.77%,P=0.003).Conclusion This simple digital preoperative templating is an accurate and reproducible process to preoperatively predict the implant size of uncemented THA.展开更多
Long-lasting SrAl2O4∶Eu, Dy phosphor was successfully prepared from a mesoporous precursor. The precursor was synthesized by templating method using nonionic Polyethylene Oxide (PEO) as surfactants, which was proved ...Long-lasting SrAl2O4∶Eu, Dy phosphor was successfully prepared from a mesoporous precursor. The precursor was synthesized by templating method using nonionic Polyethylene Oxide (PEO) as surfactants, which was proved by TG-DTG, X-Ray Diffraction (XRD) and Transmission Electron Microscopy (TEM) analysis. The analysis results indicated that regular cylindrical-to-hexagonal shaped pores with several nanometers were obtained. The structure and morphology of the SrAl2O4∶Eu, Dy phosphor by templating method was characterized by XRD and Scanning Electron Microscopy (SEM). The XRD results showed that a pure SrAl2O4 phase formed at 900 ℃ by templating method. The SEM morphologies of the obtained phosphors prepared by templating synthesis were uniform and porous multicrystalline with average diameter size of 5 μm. The broad-band UV-excited SrAl2O4∶Eu, Dy phosphor derived from a mosoporous precursor was observed at λmax=515 nm due to the transitions from the 4f65d1 to the 4f7 configurations of Eu2+ ion. The main excitation and emission intensity of the phosphor with this method were stronger than that obtained by solid state reaction method. And the obtained long-lasting phosphor with this method revealed a better afterglow compared to the phosphor prepared through solid state reaction method.展开更多
The present paper covers the synthesis of ZSM-35 molecular sieve with 1,6-hexanediamine as templating agent,the influence of the synthesis conditions, and a discussion concerning the crystal structures of the products.
Porous resorbable implants are of great interest since they may deliver bioactives or drugs, facilitate the transport of body fluids or degradation products and provide a favorable environment for cell attachment and ...Porous resorbable implants are of great interest since they may deliver bioactives or drugs, facilitate the transport of body fluids or degradation products and provide a favorable environment for cell attachment and growth. In this work we report on a method using concentrated emulsions to template interconnected solid foam materials and to produce highly porous poly(3-hydroxybutyrate) (PHB) materials. Porous PHB films were cast made from water-in-oil template emulsions including Span 80 and lithium sulphate. The films were characterized by SEM-EDX and DMA. The water uptake of the films was recorded in order to determine the fraction water available pores. The results show that the addition of lithium sulphate allows a fine tuning of the film morphology with respect to porosity and interconnected porous structure. The film porosity was determined to 51% ± 3%, 52% ± 3% and 45% ± 3% for the films made with 0%, 2.9% and 14.3% lithium sulphate in the template emulsion, respectively. The fraction water available pores was significantly lower, 11% ±3%, 38% ±12% and 48% ± 7% for films with 0%, 2.9% and 14.3% litium sulphate respectively. Differences in fraction water available pores and total porosity for the films reflects the film morphology and differences in pore interconnection.展开更多
N-doped carbons were fabricated from zeolite-templated carbon via modification with melamine and mild KOH activation. The N-doping treatment and KOH activation slightly lowered the surface areas of pristine zeolite-te...N-doped carbons were fabricated from zeolite-templated carbon via modification with melamine and mild KOH activation. The N-doping treatment and KOH activation slightly lowered the surface areas of pristine zeolite-templated carbon; nonetheless, N-doped carbons with a lower surface area exhibited much higher capacitance and cycling stability as fabricated into symmetric supercapacitor. Significantly, N-doped carbon obtained at 700°C showed a capacitance of 45.7 F/g at 0.1 A/g and 42.0 F/g at 10 A/g for the fabricated supercapacitor with 6 M KOH electrolyte, with 92% retention of initial capacitance as current density increased up to 100-fold. This performance was attributed to the dual contribution of electric double-layer capacitance and pseudo-capacitance. The assembled supercapacitor also exhibited excellent cycling stability, with 91% capacitance retention at 10 A/g after 10000 cycles.展开更多
Highly dispersed carbon microspheres(CMSs)derived from D-xylose were successfully synthesized under hydrothermal conditions and followed by further carbonization,in which F127 was used as a soft template.As-synthesize...Highly dispersed carbon microspheres(CMSs)derived from D-xylose were successfully synthesized under hydrothermal conditions and followed by further carbonization,in which F127 was used as a soft template.As-synthesized products were characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM),flourier transform infrared spectroscopy(FT-IR),thermal gravimetric(TG)and X-ray diffraction(XRD).The results showed that the morphology and structure of the CMSs prominently depended on the stirring speed during hydrothermal reaction.The resultant CMSs principally had non-porous structure without stirring and had a very smooth surface.When the stirring speed increased to 200 rpm,the synthesized mesoporous carbon microspheres at 220?C for 24 h(CMSs-5)had a uniform size distribution of 1–1.4μm and a specific surface area of 452 m^2/g.Nevertheless,with further increasing to 400 rpm,as-fabricated carbon products were mostly amorphous with a low degree of sphericity.Results demonstrated that the diameter of the products decreased with the increase of stirring speed.Furthermore,the sphericity product yield of CMSs reduced with the increase of stirring speed.XRD result showed that all the obtained samples contained partial graphite phase.In addition,a formation mechanism was proposed that involved polymerization product as the precursors for microsphere formation.The controllable and green strategy may provide a great convenience to study properties and applications of carbon microspheres.展开更多
Due to the unique physical and chemical merits including excellent electrical conductivity,superior chemical stability,and tunable carbon framework,two-dimensional(2 D)porous carbon nanosheets have drawn increasing re...Due to the unique physical and chemical merits including excellent electrical conductivity,superior chemical stability,and tunable carbon framework,two-dimensional(2 D)porous carbon nanosheets have drawn increasing research interest and demonstrated promising potentials in various applications.However,regulating the nanostructure of 2 D porous carbon nanosheets by facile and efficient strategies remains a great challenge.Herein,we develop a new strategy to construct Fe,N-codoped hierarchical porous carbon nanosheets(Fe-N-HPCNS)by using 2 D Fe-Zn layered double hydroxides(Fe-Zn-LDH)as multifunctional templates.Fe-Zn-LDH could functionalize not only as 2 D structure directing agents but also as ternary hierarchical porogens for micro-,meso-and macropores and in situ Fe dopants.This multifunctional templating strategy toward 2 D porous carbon nanosheets can improve the utilization of templates and shows great advantages against conventional procedures that additional porogens and/or dopants are often needed.展开更多
Mesoporous cerium-zirconium mixed oxides were prepared by hydrothermal method using cetyl trimethyl ammonium bromide (CTAB) as template. The effects of amount of template, pH value of solution and hydrothermal tempera...Mesoporous cerium-zirconium mixed oxides were prepared by hydrothermal method using cetyl trimethyl ammonium bromide (CTAB) as template. The effects of amount of template, pH value of solution and hydrothermal temperature on mesostructure of samples were systematically investigated. The final products were characterized by XRD, TEM, FT-IR, and BET. The results indicate that all the cerium-zirconium mixed oxides present a meso-structure. At molar ratio of n(CTAB)/n((Ce)+(Zr))= 0.15, pH value of 9, and hydrothermal temperature of 120 ℃, the samples obtained possess a specific surface area of 207.9 m2/g with pore diameter of 3.70 nm and pore volume of 0.19 cm3/g.展开更多
Porous carbon materials have exhibited a series of promising applications in supercapacitors and other research fields,yet still confronting the complicated synthetic procedures and massive usage of toxic reagents.Her...Porous carbon materials have exhibited a series of promising applications in supercapacitors and other research fields,yet still confronting the complicated synthetic procedures and massive usage of toxic reagents.Herein,we propose a green and one-pot method to produce heteroatomdoped hierarchical porous carbon materials in large-scale without any toxic reagents employed.Eventually,the as-prepared nitrogen-doped porous carbon(NPC)displays a high specific surface area of 2018 m^(2)g^(-1)together with abundant heteroatom dopants(14.8 wt%O and 1.03 wt%N).The potassium carbonate template can be recycled via a simple rinsing and re-precipitation process.Furthermore,the as-prepared nitrogen-doped porous carbon delivers a high specific capacitance of 361 F g^(-1)at 0.5 A g^(-1)and excellent rate capability of 240 F g^(-1)at 20 A g^(-1)(66.5%capacitance retention).Finally,considering the low-price raw materials and facile green synthesis procedure,the present approach can be easily scalable to prepare biomass-derived heteroatoms doped porous carbon,which is not only applicable for supercapacitor but also for other research fields.展开更多
A novel templated LiFePO_4 cathode material was prepared with linear polyacrylamide, which exhibited excellent electrochemical properties, such as a 109.3 mA·h/g capacity at a rate of C/3 and a 120 mA·h/g ca...A novel templated LiFePO_4 cathode material was prepared with linear polyacrylamide, which exhibited excellent electrochemical properties, such as a 109.3 mA·h/g capacity at a rate of C/3 and a 120 mA·h/g capacity at a rate of C/6 as well as a good cycliability. We proposed the templating mechanism based upon the precursors′ TG-DTA curves, X-ray diffraction patterns and FTIR spectra of the samples at different temperatures. A tapping-mode atomic force microscope was used to investigate the surfaces of the end products. We found that the polyacrylamide template produced metal organic compounds in the cross-linked gel precursor, and thereby modified the crystallization and particle surfaces during calcining. The template was “removed” in the end, which was partially pyrolyzed into the spiral carbon to form a conductive network with nanocrys\|talline LiFePO_4 highly monodispersed in it.展开更多
Single-handed helical phenolic resin nanofibers were synthesized through a supramolecular templating approach using the supramolecular self-assemblies of a pair of chiral low-molecular-weight amphiphiles as the templa...Single-handed helical phenolic resin nanofibers were synthesized through a supramolecular templating approach using the supramolecular self-assemblies of a pair of chiral low-molecular-weight amphiphiles as the templates and 2,4-dihydroxybenzoic acid and formaldehyde as the precursors.The phenolic resin nanofibers were characterized using field-emission scanning electron microscopy,transmission electron microscopy and diffused reflection circular dichroism.The results indicated that the chirality of the supramolecular self-assemblies was successfully transferred to the phenolic resin nanofibers.The left- and right-handed helical phenolic resin nanofibers exhibited opposite optical activity.展开更多
Lithium-ion batteries(LIBs)are considered to be among the most promising electrical storage devices for large-scale applications.In order to achieve a long lifespan and high performance for LIBs,however,it is necessar...Lithium-ion batteries(LIBs)are considered to be among the most promising electrical storage devices for large-scale applications.In order to achieve a long lifespan and high performance for LIBs,however,it is necessary to replace the traditional graphite anode with appropriate advanced anode materials.Herein,a simple and cost-effective strategy was developed to synthesize a large–scalable nitrogen-rich sulfur-doped porous carbon(NSPC)material,which when used as an anode could deliver high-rate cycle performance with a prolonged cycle life.Benefiting from the higher nitrogen content and sulfur doping,the resultant heteroatom-doped porous carbon material exhibited a significantly high initial reversible capacity of 1096 mA h g^(−1) at a current density of 0.1 A g^(−1) with a high initial columbic efficiency of more than 67%.Even at a significantly high current rate of 5 A g^(−1),prolonged cycle life over 1100 cycles with outstanding cycle performance of 695 mA h g^(−1) was achieved.The observed ultrafast lithium ion storage is attributed to the synergic effect of heteroatom-doping and abundant mesopores with a large quantity of edge defects that enable additional lithium ion storage.Density functional theory(DFT)calculations demonstrated that the introduction of N and S atoms into the porous carbon could efficiently change the charge density distributions over the carbon structure to improve the storage capacity of lithium ions and their electrochemical performance as an anode in LIBs.展开更多
Macroporous hydrogels are water-swollen polymer networks with porous structures beyond the mesh size.They provide high specific surface areas and hieratical mass transfer channels which are desired for emerging applic...Macroporous hydrogels are water-swollen polymer networks with porous structures beyond the mesh size.They provide high specific surface areas and hieratical mass transfer channels which are desired for emerging applications including cell culturing,bio-separation,and drug delivery.A variety of approaches have been developed to fabricate macroporous hydrogels,including gas foaming,porogen templating,phase separation,3D printing,etc.Alternatively,ice templating utilizes the crystallization of water as the porogenation mechanism which doesn't need the leaching of porogens.展开更多
Gold nanoclusters(AuNCs)are ultrasmall(<2 nm)aggregates of gold atoms that exhibit discrete electronic states,size-dependent photoluminescence,and exceptional biocompatibility,making them ideal candidates for thera...Gold nanoclusters(AuNCs)are ultrasmall(<2 nm)aggregates of gold atoms that exhibit discrete electronic states,size-dependent photoluminescence,and exceptional biocompatibility,making them ideal candidates for theranostic applications.Their tunable surface chemistry enables targeted delivery,while strong near-infrared emission and environmental responsiveness allow for sensitive detection and deep-tissue imaging.Recent advances have revealed that controlled assembly of AuNCs into higher-order architectures-guided by biological scaffolds such as nucleic acids,peptides,and proteins-can markedly enhance their optical and electronic properties through aggregation-induced emission(AiE)and stabilization of surface ligands.This review summarizes recent progress in the design and biomedical applications of AuNC assemblies generated using biomolecules as structure-directing scaffolds.Covalent and noncovalent interactions with biomolecules enable the formation of well-defined one-,two-,and three-dimensional structures with tunable morphologies and sizes.These assemblies display distinctive photophysical behaviors that have been exploited for biosensing,bioimaging,and therapeutic applications in both cellular and in vivo models.Compared with individual AuNCs,assembled systems offer improved uptake,prolonged circulation,and efficient clearance,while protecting labile cargos such as nucleic acids and proteins.Moreover,their ordered and defined architectures can be engineered for controlled drug release and synergistic photo-or radiotherapeutic effects.Despite these advances,fundamental understanding of how structural organization governs photophysical responses remains limited.Elucidating parameters such as intercluster spacing and loading density will be essential for optimizing performance.Overall,biologically guided AuNC assemblies represent a powerful platform for multifunctional biosensing and therapy,bridging nanoscale design with biological function.展开更多
High-temperature-annealed Al N(HTA-Al N) templates provide ideal substrates for high-quality Al Ga N epitaxy. However, the significant compressive stress accumulated within the Al Ga N layer makes it challenging to ac...High-temperature-annealed Al N(HTA-Al N) templates provide ideal substrates for high-quality Al Ga N epitaxy. However, the significant compressive stress accumulated within the Al Ga N layer makes it challenging to achieve a smooth surface free of hexagonal hillocks on these templates. To address this issue, we investigate the mechanism of compressive stress accumulation during the growth of Al Ga N-based epilayers on HTA-Al N templates using in-situ curvature analysis in this study. To verify the mechanism, a low-Al-content Al Ga N interlayer is introduced between the Al N epilayer and the subsequent Al Ga N epilayer. The larger a-plane lattice constant of this interlayer relative to the Al Ga N epilayer slows the accumulation rate of compressive stress. The hexagonal hillock can be effectively suppressed and the surface of Al Ga N epilayer can be significantly regulated by adopting various low-Al-content Al Ga N interlayers. This work provides a comprehension on the stress accumulation mechanism in Al Ga N epilayers and a feasible method to obtain hillock-free surface of Al Ga N epilayers on HTA-Al N templates,which will be beneficial for fabricating Al Ga N based devices.展开更多
Structural displacement monitoring faces significant challenges under complex environmental conditions due to the loss or degradation of target features,making it difficult for traditional methods to ensure high accur...Structural displacement monitoring faces significant challenges under complex environmental conditions due to the loss or degradation of target features,making it difficult for traditional methods to ensure high accuracy and robustness.Therefore,this study proposes a structural displacement identification and quantification method that integrates YOLOv8n with an improved edge-orientation gradient-based template matching algorithm.By combining deep learning techniques with traditional template matching methods,the accuracy and robustness of monitoring are enhanced under adverse conditions such as noise and extremely low illumination.Specifically,in the edge-orientation gradient matching stage,the Canny-Devernay sub-pixel edge detection technique and an improved ellipse-fitting method are employed for sub-pixel edge extraction,and a five-level Gaussian pyramid structure is introduced to accelerate the matching speed.Experimental results show that the proposed method achieves high-precision displacement monitoring under sufficient illumination,and it maintains stable target localization and displacement quantification performance under conditions of noise interference and extremely low illumination.Notably,under salt-and-pepper noise interference,although YOLOv8n maintains a high level of localization confidence,the accuracy of gradient matching deteriorates,resulting in a root-mean-square error(RMSE)of 0.035 mm.This finding reveals the differential impact of various noise types on different stages of the algorithm.The proposed method offers a novel technological approach for precise structural displacement monitoring in complex environments.展开更多
文摘Since the discovery of ZSM-5 molecular sieves as a promising catalyst material, the synthesis of ZSM-5 has been investigated in great detail. In the first synthesis of ZSM-5,tetrapropylammonium(TPA) was used as the templating agent. However, the industrial manufacture and application of ZSM-5 molecular sieves arc limited because TPA, the templating agent, is expensive. In the attempt to search for a suitable substitute for TPA,
文摘AIM: To investigate the correlation between preoperative measurement in total knee arthroplasty and the prosthetic size implanted. METHODS: A prospective double-blind study of 50 arthroplasties was performed. Firstly, the reliability and correspondence between the size of said measurement and the actual implant utilized was determined. Secondly, the existing correlation between the intra- and interobserver determinations with the intraclass correlation coefficient was analyzed. RESULTS: An overall correspondence of 54%, improving up to 92% when the measured size admitted a difference of one size, was found. Good intra- and interobserver reliability with an intraclass correlation coefficient greater than 0.90(P < 0.001) was also discovered. CONCLUSION: Agreement between the preoperative measurement with standardized acetate templates and the prosthetic size implanted can be considered satisfactory. We thus conclude it is a reproducible technique.
基金Fundamental Research Key Project of Shanghai (06JC14060)
文摘Ceria nanotubes with high CO conversion activity by means of carbon nanotubes as removable templates in the simple liquid phase process were fabricated under moderate conditions. The pristine CNTs were first pretreated by refluxing in a 30% nitric acid solution at 140 ℃ for 24 h, then dispersed in an ethanolic Ce（NO3）3.6H2O solution with ultrasonic radiation at room temperature for 1 h. Under vigorous stirring, NaOH solution was added drop by drop into the above ethanolic solution until the pH value was 10. The product was collected and repeatedly washed with ethanol and on drying at 60 ℃, the CeO2/CNT composites were obtained. Then, the as-prepared composites were heated at 450 ℃ in an air atmosphere for 30 min to remove CNTs. The ceria nanotubes were characterized by X-Ray Diffraction （XRD）, Transmission Electron Microscopy （TEM）, and X-Ray Photoelectron Spectrum （XPS）. The results showed that the ceria nanotubes were polycrystalline face-centered cubic phase and were composed of lots of dense cefia nanoparficles. The diameter of cefia nanotubes was about 40-50 nm. Catalytic activity of the product for CO oxidation was carded out at the region of 30-300 ℃ in a U-shaped quartz reactor with feeding about 0.15 g of the catalyst, which was loaded on Al2O3 carder. The inlet gas composition was 1.0% CO and 28% O2 with N2 as balance, and the rate of flow was kept at 40 ml/min. The catalytic products were analyzed by gas chromatography. The as-repared CeO2 nanotubes showed higher CO oxidation activity, which indicated that the morphology of ceria products affected the catalytic performance. The ceria nanotubes supported on Al2O3 demonstrated that conversion temperature for CO oxidation to CO2 was lower than that for bulk catalysts.
文摘AIM To analyze planning total hip arthroplasty(THA) with an additional anteroposterior hip view may increases the accuracy of preoperative planning in THA.METHODS We conducted prospective digital planning in 100 consecutive patients: 50 of these procedures were planned using pelvic overview only(first group), and the other 50 procedures were planned using pelvic overview plus antero-posterior(a.p.) hip view(second group). The planning and the procedure of each patient were performed exclusively by the senior surgeon. Fifty procedures with retrospective analogues planning were used as the control group(group zero). After the procedure, the planning was compared with the eventually implanted components(cup and stem). For statistic analysis the x^2 test was used for nominal variables and the t test was used for a comparison of continuous variables.RESULTS Preoperative planning with an additional a.p. hip view(second group) significantly increased the exact component correlation when compared to pelvic overview only(first group) for both the acetabular cup and the femoral stem(76% cup and 66% stem vs 54% cup and 32% stem). When considering planning ± 1 size, the accuracy in the second group was 96%(48 of 50 patients) for the cup and 94% for the stem(47 of 50patients). In the analogue control group(group zero), an exact correlation was observed in only 1/3 of the cases.CONCLUSION Digital THA planning performed by the operating surgeon and based on additional a.p. hip view significantly increases the correlation between preoperative planning and eventual implant sizes.
基金Supported by the Health Research Program of Ministry of Health(201302007)
文摘Objective To introduce a simple preoperative digital templating in uncemented total hip arthroplasty(THA) and to determine its accuracy for preoperative size selection of the prostheses.Methods A prospective study of digital planned THAs was performed on 90 hips with different types of prostheses from August 2013 to Angust 2014.The plastic templates of different types of prostheses were scanned for desired digital templating and the scanned images were then processed to the transparent,digital templates using Photoshop software.We calibrated the scales of the digital templates with the preoperative radiographs,and then selected the right size of the component.The preoperatively digital planned component sizes were compared to the actual sizes used in the operation,as well as the preoperatively traditional planned sizes.Results In either cup or stem templating,no difference was found among the groups with different types of prostheses,and the accuracy of digital templating was statistically higher than traditional templating.In cup templating,digital planned and implanted cup sizes were identical in 43.33% of the cases,78.89% of the cup sizes were predicted within 1 size(± 2mm) and 95.56% were predicted within 2 sizes(±4 mm),all significantly higher than the results of traditional planned sizes(30.00%,P=0.044;61.11%,P=0.007;82.22%,P=0.004).The exact femoral stem size was predicted in 40.00% of cases using the digital templating,84.44% of stem sizes were predicted within 1 size,and 93.33% within 2 sizes,better than using traditional templating(25.56%,P=0.028;53.33%,P<0.001;77.77%,P=0.003).Conclusion This simple digital preoperative templating is an accurate and reproducible process to preoperatively predict the implant size of uncemented THA.
基金the National Natural Science Foundation of China (20376009)
文摘Long-lasting SrAl2O4∶Eu, Dy phosphor was successfully prepared from a mesoporous precursor. The precursor was synthesized by templating method using nonionic Polyethylene Oxide (PEO) as surfactants, which was proved by TG-DTG, X-Ray Diffraction (XRD) and Transmission Electron Microscopy (TEM) analysis. The analysis results indicated that regular cylindrical-to-hexagonal shaped pores with several nanometers were obtained. The structure and morphology of the SrAl2O4∶Eu, Dy phosphor by templating method was characterized by XRD and Scanning Electron Microscopy (SEM). The XRD results showed that a pure SrAl2O4 phase formed at 900 ℃ by templating method. The SEM morphologies of the obtained phosphors prepared by templating synthesis were uniform and porous multicrystalline with average diameter size of 5 μm. The broad-band UV-excited SrAl2O4∶Eu, Dy phosphor derived from a mosoporous precursor was observed at λmax=515 nm due to the transitions from the 4f65d1 to the 4f7 configurations of Eu2+ ion. The main excitation and emission intensity of the phosphor with this method were stronger than that obtained by solid state reaction method. And the obtained long-lasting phosphor with this method revealed a better afterglow compared to the phosphor prepared through solid state reaction method.
文摘The present paper covers the synthesis of ZSM-35 molecular sieve with 1,6-hexanediamine as templating agent,the influence of the synthesis conditions, and a discussion concerning the crystal structures of the products.
文摘Porous resorbable implants are of great interest since they may deliver bioactives or drugs, facilitate the transport of body fluids or degradation products and provide a favorable environment for cell attachment and growth. In this work we report on a method using concentrated emulsions to template interconnected solid foam materials and to produce highly porous poly(3-hydroxybutyrate) (PHB) materials. Porous PHB films were cast made from water-in-oil template emulsions including Span 80 and lithium sulphate. The films were characterized by SEM-EDX and DMA. The water uptake of the films was recorded in order to determine the fraction water available pores. The results show that the addition of lithium sulphate allows a fine tuning of the film morphology with respect to porosity and interconnected porous structure. The film porosity was determined to 51% ± 3%, 52% ± 3% and 45% ± 3% for the films made with 0%, 2.9% and 14.3% lithium sulphate in the template emulsion, respectively. The fraction water available pores was significantly lower, 11% ±3%, 38% ±12% and 48% ± 7% for films with 0%, 2.9% and 14.3% litium sulphate respectively. Differences in fraction water available pores and total porosity for the films reflects the film morphology and differences in pore interconnection.
基金financially supported by the National Natural Science Foundation of China (No. 21506184)Hunan 2011 Collaborative Center of Chemical Technologies for Environmental Benignity & Efficient Resource Utilization, and State Key Laboratory of Powder Metallurgy of Central South University
文摘N-doped carbons were fabricated from zeolite-templated carbon via modification with melamine and mild KOH activation. The N-doping treatment and KOH activation slightly lowered the surface areas of pristine zeolite-templated carbon; nonetheless, N-doped carbons with a lower surface area exhibited much higher capacitance and cycling stability as fabricated into symmetric supercapacitor. Significantly, N-doped carbon obtained at 700°C showed a capacitance of 45.7 F/g at 0.1 A/g and 42.0 F/g at 10 A/g for the fabricated supercapacitor with 6 M KOH electrolyte, with 92% retention of initial capacitance as current density increased up to 100-fold. This performance was attributed to the dual contribution of electric double-layer capacitance and pseudo-capacitance. The assembled supercapacitor also exhibited excellent cycling stability, with 91% capacitance retention at 10 A/g after 10000 cycles.
基金supported financially by the Outstanding Youth Science Fund of Shaanxi Province(No.2018JC-028)the fund of Beijing Key Laboratory of Quality Evaluation Technology for Hygiene and Safety of Plastics,Beijing Technology and Business University(No.51772243)+1 种基金the Innovation Team Plan of Shaanxi Province(No.2017KCT-17)the National Natural Science Foundation of China(No.51772243).
文摘Highly dispersed carbon microspheres(CMSs)derived from D-xylose were successfully synthesized under hydrothermal conditions and followed by further carbonization,in which F127 was used as a soft template.As-synthesized products were characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM),flourier transform infrared spectroscopy(FT-IR),thermal gravimetric(TG)and X-ray diffraction(XRD).The results showed that the morphology and structure of the CMSs prominently depended on the stirring speed during hydrothermal reaction.The resultant CMSs principally had non-porous structure without stirring and had a very smooth surface.When the stirring speed increased to 200 rpm,the synthesized mesoporous carbon microspheres at 220?C for 24 h(CMSs-5)had a uniform size distribution of 1–1.4μm and a specific surface area of 452 m^2/g.Nevertheless,with further increasing to 400 rpm,as-fabricated carbon products were mostly amorphous with a low degree of sphericity.Results demonstrated that the diameter of the products decreased with the increase of stirring speed.Furthermore,the sphericity product yield of CMSs reduced with the increase of stirring speed.XRD result showed that all the obtained samples contained partial graphite phase.In addition,a formation mechanism was proposed that involved polymerization product as the precursors for microsphere formation.The controllable and green strategy may provide a great convenience to study properties and applications of carbon microspheres.
基金financially supported by the National Natural Science Foundation of China(Nos.51925308 and 51872336)the Leading Scientific,Technical and Innovation Talents of Guangdong Special Support Program(No.2017TX04C248)+3 种基金the Pearl River Talent Plan of Guangdong(No.2017GC010612)Natural Science Foundation of Guangdong(No.2021A1515011617)the Fundamental Research Funds for the Central Universities(No.20lgzd18)the Science and Technology Program of Guangzhou(Nos.202102021111 and 202002020041)。
文摘Due to the unique physical and chemical merits including excellent electrical conductivity,superior chemical stability,and tunable carbon framework,two-dimensional(2 D)porous carbon nanosheets have drawn increasing research interest and demonstrated promising potentials in various applications.However,regulating the nanostructure of 2 D porous carbon nanosheets by facile and efficient strategies remains a great challenge.Herein,we develop a new strategy to construct Fe,N-codoped hierarchical porous carbon nanosheets(Fe-N-HPCNS)by using 2 D Fe-Zn layered double hydroxides(Fe-Zn-LDH)as multifunctional templates.Fe-Zn-LDH could functionalize not only as 2 D structure directing agents but also as ternary hierarchical porogens for micro-,meso-and macropores and in situ Fe dopants.This multifunctional templating strategy toward 2 D porous carbon nanosheets can improve the utilization of templates and shows great advantages against conventional procedures that additional porogens and/or dopants are often needed.
基金Project(CHCL0501) supported by Hubei Provincial Open Fund of Key Laboratory of Catalytic Material Science and Technology
文摘Mesoporous cerium-zirconium mixed oxides were prepared by hydrothermal method using cetyl trimethyl ammonium bromide (CTAB) as template. The effects of amount of template, pH value of solution and hydrothermal temperature on mesostructure of samples were systematically investigated. The final products were characterized by XRD, TEM, FT-IR, and BET. The results indicate that all the cerium-zirconium mixed oxides present a meso-structure. At molar ratio of n(CTAB)/n((Ce)+(Zr))= 0.15, pH value of 9, and hydrothermal temperature of 120 ℃, the samples obtained possess a specific surface area of 207.9 m2/g with pore diameter of 3.70 nm and pore volume of 0.19 cm3/g.
基金supported by the National Natural Science Foundation of China(No.51303170)the National Science Centre,Poland within BEETHOVEN UMO-2016/23/G/ST5/04200。
文摘Porous carbon materials have exhibited a series of promising applications in supercapacitors and other research fields,yet still confronting the complicated synthetic procedures and massive usage of toxic reagents.Herein,we propose a green and one-pot method to produce heteroatomdoped hierarchical porous carbon materials in large-scale without any toxic reagents employed.Eventually,the as-prepared nitrogen-doped porous carbon(NPC)displays a high specific surface area of 2018 m^(2)g^(-1)together with abundant heteroatom dopants(14.8 wt%O and 1.03 wt%N).The potassium carbonate template can be recycled via a simple rinsing and re-precipitation process.Furthermore,the as-prepared nitrogen-doped porous carbon delivers a high specific capacitance of 361 F g^(-1)at 0.5 A g^(-1)and excellent rate capability of 240 F g^(-1)at 20 A g^(-1)(66.5%capacitance retention).Finally,considering the low-price raw materials and facile green synthesis procedure,the present approach can be easily scalable to prepare biomass-derived heteroatoms doped porous carbon,which is not only applicable for supercapacitor but also for other research fields.
文摘A novel templated LiFePO_4 cathode material was prepared with linear polyacrylamide, which exhibited excellent electrochemical properties, such as a 109.3 mA·h/g capacity at a rate of C/3 and a 120 mA·h/g capacity at a rate of C/6 as well as a good cycliability. We proposed the templating mechanism based upon the precursors′ TG-DTA curves, X-ray diffraction patterns and FTIR spectra of the samples at different temperatures. A tapping-mode atomic force microscope was used to investigate the surfaces of the end products. We found that the polyacrylamide template produced metal organic compounds in the cross-linked gel precursor, and thereby modified the crystallization and particle surfaces during calcining. The template was “removed” in the end, which was partially pyrolyzed into the spiral carbon to form a conductive network with nanocrys\|talline LiFePO_4 highly monodispersed in it.
基金supported by the Natural Science Foundation of Jiangsu Province(No.BK2011354)the Priority Academic Program Development of Jiangsu High Education Institutions(PAPD,No. YX10900114)the National Natural Science Foundation of China(No.21104053)
文摘Single-handed helical phenolic resin nanofibers were synthesized through a supramolecular templating approach using the supramolecular self-assemblies of a pair of chiral low-molecular-weight amphiphiles as the templates and 2,4-dihydroxybenzoic acid and formaldehyde as the precursors.The phenolic resin nanofibers were characterized using field-emission scanning electron microscopy,transmission electron microscopy and diffused reflection circular dichroism.The results indicated that the chirality of the supramolecular self-assemblies was successfully transferred to the phenolic resin nanofibers.The left- and right-handed helical phenolic resin nanofibers exhibited opposite optical activity.
基金supported by The National Key Research and Development Program of China(2017YFA0206500)Key Program of National Natural Science Foundation of China(51732002)+3 种基金Distinguished Scientist Program at BUCT(buctylkxj02)the Start-Up Fund for Talent Introduction of Beijing University of Chemical Technology(buctrc202007)Australian Research Council(ARC,DP 190103881 and FL 190100126)support from Beijing Advanced Innovation Center for Soft Matter Science and Engineering,and BUCT.
文摘Lithium-ion batteries(LIBs)are considered to be among the most promising electrical storage devices for large-scale applications.In order to achieve a long lifespan and high performance for LIBs,however,it is necessary to replace the traditional graphite anode with appropriate advanced anode materials.Herein,a simple and cost-effective strategy was developed to synthesize a large–scalable nitrogen-rich sulfur-doped porous carbon(NSPC)material,which when used as an anode could deliver high-rate cycle performance with a prolonged cycle life.Benefiting from the higher nitrogen content and sulfur doping,the resultant heteroatom-doped porous carbon material exhibited a significantly high initial reversible capacity of 1096 mA h g^(−1) at a current density of 0.1 A g^(−1) with a high initial columbic efficiency of more than 67%.Even at a significantly high current rate of 5 A g^(−1),prolonged cycle life over 1100 cycles with outstanding cycle performance of 695 mA h g^(−1) was achieved.The observed ultrafast lithium ion storage is attributed to the synergic effect of heteroatom-doping and abundant mesopores with a large quantity of edge defects that enable additional lithium ion storage.Density functional theory(DFT)calculations demonstrated that the introduction of N and S atoms into the porous carbon could efficiently change the charge density distributions over the carbon structure to improve the storage capacity of lithium ions and their electrochemical performance as an anode in LIBs.
基金supported by the National Natural Science Foundation of China(grant Nos.52273112,U20A6001,22105167)the Start-up funding of Ningbo Research Institute of Zhejiang University(grant No.20201203Z0193).
文摘Macroporous hydrogels are water-swollen polymer networks with porous structures beyond the mesh size.They provide high specific surface areas and hieratical mass transfer channels which are desired for emerging applications including cell culturing,bio-separation,and drug delivery.A variety of approaches have been developed to fabricate macroporous hydrogels,including gas foaming,porogen templating,phase separation,3D printing,etc.Alternatively,ice templating utilizes the crystallization of water as the porogenation mechanism which doesn't need the leaching of porogens.
基金NR SEQUOIA(ANR-22-CE18-0006)Nan0Gold(ANR-22-CE29-0022)+3 种基金SAMURAI(ANR-24-CE19-2073-01)Wilive(ANR-24-CE09-2351-03)EUR CBH-EUR-GS(ANR-17-EURE 0003)for their financial supportthe French National Research Agency(Labex ARCANE,ANR-11-LABX-003 and CBH-EUR-GS,ANR-17-EURE-0003)that supported part of this study.
文摘Gold nanoclusters(AuNCs)are ultrasmall(<2 nm)aggregates of gold atoms that exhibit discrete electronic states,size-dependent photoluminescence,and exceptional biocompatibility,making them ideal candidates for theranostic applications.Their tunable surface chemistry enables targeted delivery,while strong near-infrared emission and environmental responsiveness allow for sensitive detection and deep-tissue imaging.Recent advances have revealed that controlled assembly of AuNCs into higher-order architectures-guided by biological scaffolds such as nucleic acids,peptides,and proteins-can markedly enhance their optical and electronic properties through aggregation-induced emission(AiE)and stabilization of surface ligands.This review summarizes recent progress in the design and biomedical applications of AuNC assemblies generated using biomolecules as structure-directing scaffolds.Covalent and noncovalent interactions with biomolecules enable the formation of well-defined one-,two-,and three-dimensional structures with tunable morphologies and sizes.These assemblies display distinctive photophysical behaviors that have been exploited for biosensing,bioimaging,and therapeutic applications in both cellular and in vivo models.Compared with individual AuNCs,assembled systems offer improved uptake,prolonged circulation,and efficient clearance,while protecting labile cargos such as nucleic acids and proteins.Moreover,their ordered and defined architectures can be engineered for controlled drug release and synergistic photo-or radiotherapeutic effects.Despite these advances,fundamental understanding of how structural organization governs photophysical responses remains limited.Elucidating parameters such as intercluster spacing and loading density will be essential for optimizing performance.Overall,biologically guided AuNC assemblies represent a powerful platform for multifunctional biosensing and therapy,bridging nanoscale design with biological function.
基金supported by the National Key R&D Program of China (Grant No. 2022YFB3605000)the National Natural Science Foundation of China (Nos. 62004127, 61725403, 62121005, 61922078, 61827813, and 62004196)+1 种基金the Youth Innovation Promotion Association of Chinese Academy of Sciencesthe Youth Talent Promotion Project of the Chinese Institute of Electronics (No. 2020QNRC001)。
文摘High-temperature-annealed Al N(HTA-Al N) templates provide ideal substrates for high-quality Al Ga N epitaxy. However, the significant compressive stress accumulated within the Al Ga N layer makes it challenging to achieve a smooth surface free of hexagonal hillocks on these templates. To address this issue, we investigate the mechanism of compressive stress accumulation during the growth of Al Ga N-based epilayers on HTA-Al N templates using in-situ curvature analysis in this study. To verify the mechanism, a low-Al-content Al Ga N interlayer is introduced between the Al N epilayer and the subsequent Al Ga N epilayer. The larger a-plane lattice constant of this interlayer relative to the Al Ga N epilayer slows the accumulation rate of compressive stress. The hexagonal hillock can be effectively suppressed and the surface of Al Ga N epilayer can be significantly regulated by adopting various low-Al-content Al Ga N interlayers. This work provides a comprehension on the stress accumulation mechanism in Al Ga N epilayers and a feasible method to obtain hillock-free surface of Al Ga N epilayers on HTA-Al N templates,which will be beneficial for fabricating Al Ga N based devices.
基金supported by the National Natural Science Foundation of China(No.52408533)the Natural Science Foundation of Shandong Province(No.ZR2024QE408)+3 种基金the University of Jinan Disciplinary Cross-Convergence Construction Project 2023(XKJC202310)the Municipal and School Integration Development Strategic Project of Jinan City(JNSX2023023)Natural Science Foundation of Tianjin(24JCQNJC00870)Doctoral Fund Support Project of University of Jinan(XRC2563).
文摘Structural displacement monitoring faces significant challenges under complex environmental conditions due to the loss or degradation of target features,making it difficult for traditional methods to ensure high accuracy and robustness.Therefore,this study proposes a structural displacement identification and quantification method that integrates YOLOv8n with an improved edge-orientation gradient-based template matching algorithm.By combining deep learning techniques with traditional template matching methods,the accuracy and robustness of monitoring are enhanced under adverse conditions such as noise and extremely low illumination.Specifically,in the edge-orientation gradient matching stage,the Canny-Devernay sub-pixel edge detection technique and an improved ellipse-fitting method are employed for sub-pixel edge extraction,and a five-level Gaussian pyramid structure is introduced to accelerate the matching speed.Experimental results show that the proposed method achieves high-precision displacement monitoring under sufficient illumination,and it maintains stable target localization and displacement quantification performance under conditions of noise interference and extremely low illumination.Notably,under salt-and-pepper noise interference,although YOLOv8n maintains a high level of localization confidence,the accuracy of gradient matching deteriorates,resulting in a root-mean-square error(RMSE)of 0.035 mm.This finding reveals the differential impact of various noise types on different stages of the algorithm.The proposed method offers a novel technological approach for precise structural displacement monitoring in complex environments.
