采用粉末冶金发泡法制备了Fe Al Fe、Ti Al Ti泡沫铝芯三明治结构 ,研究了泡沫铝芯的膨胀规律 ,分析了面板与泡沫铝芯的冶金结合过程 ,提出了微观结合机制。试验发现 ,结合界面由扩散反应形成的金属间化合物以及冷却得到的凝固组织两部...采用粉末冶金发泡法制备了Fe Al Fe、Ti Al Ti泡沫铝芯三明治结构 ,研究了泡沫铝芯的膨胀规律 ,分析了面板与泡沫铝芯的冶金结合过程 ,提出了微观结合机制。试验发现 ,结合界面由扩散反应形成的金属间化合物以及冷却得到的凝固组织两部分组成 ,从而形成良好的冶金结合。展开更多
AIM:To evaluate the efficacy and safety of the laparoscopic approaches for parastomal hernia repair reported in the literature.METHODS:A systematic review of PubMed and MEDLINE databases was conducted using various co...AIM:To evaluate the efficacy and safety of the laparoscopic approaches for parastomal hernia repair reported in the literature.METHODS:A systematic review of PubMed and MEDLINE databases was conducted using various combination of the following keywords:stoma repair,laparoscopic,parastomal,and hernia.Case reports,studies with less than 5 patients,and articles not written in English were excluded.Eligible studies were further scrutinized with the 2011 levels of evidence from the Oxford Centre for Evidence-Based Medicine.Two authors reviewed and analyzed each study.If there was any discrepancy between scores,the study in question was referred to another author.A meta-analysis was performed using both random and fixed-effect models.Publication bias was evaluated using Begg's funnel plot and Egger's regression test.The primary outcome analyzed was recurrence of parastomal hernia.Secondary outcomes were mesh infection,surgical site infection,obstruction requiring reoperation,death,and other complications.Studies were grouped by operative technique where indicated.Except for recurrence,most postoperative morbidities were reported for the overall cohort and not by approach so they were analyzed across approach.RESULTS:Fifteen articles with a total of 469 patients were deemed eligible for review.Most postoperative morbidities were reported for the overall cohort,and not by approach.The overall postoperative morbidity rate was 1.8%(95%CI:0.8-3.2),and there was no difference between techniques.The most common postoperative complication was surgical site infection,which was seen in 3.8%(95%CI:2.3-5.7).Infected mesh was observed in 1.7%(95%CI:0.7-3.1),and obstruction requiring reoperation also occurred in 1.7%(95%CI:0.7-3.0).Other complications such as ileus,pneumonia,or urinary tract infection were noted in16.6%(95%CI:11.9-22.1).Eighty-one recurrences were reported overall for a recurrence rate of 17.4%(95%CI:9.5-26.9).The recurrence rate was 10.2%(95%CI:3.9-19.0) for the modified laparoscopic Sugarbaker approach,whereas the展开更多
Objective Development of monoclonal antibody based sandwich enzyme linked immunosorbant assay （sELISA） for rapid detection of Salmonella enterica serovar typhi （S. typhi） from food and water samples and optimizati...Objective Development of monoclonal antibody based sandwich enzyme linked immunosorbant assay （sELISA） for rapid detection of Salmonella enterica serovar typhi （S. typhi） from food and water samples and optimization of enrichment procedures for use with the developed sELISA to increase the detection sensitivity of the assay. Methods Spleen cells from BALB/c mice immunized with flagellin （H=d） antigen of S. typhi were fused with Sp2/0 myeloma cells. The hybridoma cell line specific to H=d antigen was established, characterized and ascites raised against one of these clones. The hyperimmune serum to flagellin antigen was raised in New Zealand White rabbits. An sELISA was developed using polyclonal antibody as capture and monoclonal antibody as detection antibody. To design the efficient culture strategies for use with the sELISA, different pre-enrichment and enrichment broths were evaluated. The media included buffered peptone water （BPW） and brain heart infusion broth for pre-enrichment and selenite F broth and Rappaport-Vassiliadis broth as enrichment broths. The developed sELISA with preceding enrichment step in BPW （Enrichment-ELISA） was evaluated in various food samples artificially inoculated with S. typhi bacteria. Various food （30） and water （35） samples collected from field were also tested by Enrichment-ELISA and culture method. Results Out of four specific clones to H=d antigen, one clone （# 2/56, IgG2a isotype） was used in sELISA. The sELISA had the detection limit of 10^4-10^5 cfu of S. typhi. Of the various broths used with sELISA, BPW was found to yield maximum ELISA values. Enrichment-ELISA, when tested in artificially inoculated food samples, generally, could detect 10^2 S. typhi cfu/mL within 10 h from various food rinses （meat, vegetable） and milk samples. After overnight enrichment in BPW, as less as 2 bacteria per 10 mL of milk, meat rinse, and chicken rinse could be detected. Only one of the field samples （water） gave false positive result by Enrichment-展开更多
A new type of ultra-lightweight metallic lattice structure (named as the X-type structure) is reported. This periodic structure was formed by two groups of staggered struts in the traditional pyramid structure, and fa...A new type of ultra-lightweight metallic lattice structure (named as the X-type structure) is reported. This periodic structure was formed by two groups of staggered struts in the traditional pyramid structure, and fabricated by folding expanded metal sheet along rows of offset nodes and then brazing the folded structure (as the core) with top and bottom facesheets to form sandwich panels. The out-of-plane compressive and shear properties of the X-type lattice sandwich structure were investigated experimentally and compared to those of the sandwich having a pyramidal truss core. It is found that the formation of the 2-dimensional staggered nodes can effectively make the X-type structure more resistant to inelastic and plastic buckling under both compression and shear loading than the pyramidal lattice truss. Obtained results show that the compressive and shear peak strengths of the X-type lattice structure are about 30% higher than those of the pyramidal lattice truss having the same relative density.展开更多
Owing to the high power density,long cycle life and maintain-free,micro-supercapacitors(MSCs)stand out as preferred miniaturized energy source for themiscellaneous autonomous electronic components.However,the shortage...Owing to the high power density,long cycle life and maintain-free,micro-supercapacitors(MSCs)stand out as preferred miniaturized energy source for themiscellaneous autonomous electronic components.However,the shortage of energy density is the main stumbling block for their practical applications.To solve this energy issue,constructing a three-dimensional(3D)electrode within the limited footprint area is proposed as a new solution for improving the energy storage capacity ofMSCs.In the last few years,extensive efforts have been devoted to developing 3D electrodes for MSCs,and significant progress and breakthrough have been achieved.While,there is still lack of systematic summary on the 3D electrode design strategies.To this end,it is imperative to outline the basic design conception,summarize the current states,and discuss the future research about 3D electrodes in MSCs based on the latest development.展开更多
This paper presents an experimental study of a novel K-Cor sandwich structure rein- forced with partially-cured Z-pins. The influence of pultrusion processing parameters on Z-pins characteristics was studied and the e...This paper presents an experimental study of a novel K-Cor sandwich structure rein- forced with partially-cured Z-pins. The influence of pultrusion processing parameters on Z-pins characteristics was studied and the effect of Z-pins on mechanical properties was disclosed. Differential scanning calorimetry （DSC） and optical microscopy （OM） methods were employed to determine the curing degree of as-prepared Z-pins and observe the implanted Z-pins in the K-Cor structure. These partially-cured Z-pins were treated with a stronger bonding link between face sheets and the foam core by means of a hot-press process, thereby decreasing burrs and cracking defects when the Z-pins were implanted into the Rohacell foam core. The results of the out-of-plane tensile tests and the climbing drum peel （CDP） tests showed that K-Cor structures exhibited superior mechanical performance as compared to X-Cor and blank foam core. The observed results of failure modes revealed that an effective bonding link between the foam core and face sheets that was provided from partially-cured Z-pins contributed to the enhanced mechan- ical performances of K-Cor sandwich structures.展开更多
We report the experimental observations of the segregation patterns in initially well mixed copper and glass spheres subjected to a vertical sinusoidal vibration at differ-ent values of acceleration G and frequency f....We report the experimental observations of the segregation patterns in initially well mixed copper and glass spheres subjected to a vertical sinusoidal vibration at differ-ent values of acceleration G and frequency f. A segregation phase diagram is obtained, which includes Brazil nut (BN), Reversed-BN (RBN) and sandwich segregation patterns at different G and f. The stable RBN segregation is experimen-tally found for the first time, in which large heavy particles move down to the bottom and form the lower-layer while small particles rise to the top and form an upper-layer. The boundary values (G, f), which separate regions of different patterns, depend on system’s initial condition, i.e. hysteresis exists.展开更多
Truss core sandwich panels reinforced by carbon fibers were assembled with bonded laminate facesheets and carbon fiber reinforced truss cores. The top and bottom facesheets were interconnected with truss cores. Both e...Truss core sandwich panels reinforced by carbon fibers were assembled with bonded laminate facesheets and carbon fiber reinforced truss cores. The top and bottom facesheets were interconnected with truss cores. Both ends of the truss cores were embedded into four layers of top and bottom facesheets. The mechanical properties of truss core sandwich panels were then investigated under out-of-plane and in-plane compression loadings to reveal the failure mechanisms of sandwich panels. Experimental results indicated that the mechanical behavior of sandwich structure under in-plane loading is dominated by the buckling and debonding of facesheets.展开更多
An effective single layered finite element （FE） computational model is proposed to predict the structural behavior of lightweight sandwich panels having two dimensional （2D） prismatic or three dimensional （3D） t...An effective single layered finite element （FE） computational model is proposed to predict the structural behavior of lightweight sandwich panels having two dimensional （2D） prismatic or three dimensional （3D） truss cores. Three different types of cellular core topology are considered： pyramidal truss core （3D）, Kagome truss core （3D） and corrugated core （2D）, representing three kinds of material anisotropy： orthotropic, monoclinic and general anisotropic. A homogenization technique is developed to obtain the homogenized macroscopic stiffness properties of the cellular core. In comparison with the results obtained by using detailed FE model, the single layered computational model can give acceptable predictions for both the static and dynamic behaviors of orthotropic truss core sandwich panels. However, for non-orthotropic 3D truss cores, the predictions are not so well. For both static and dynamic behaviors of a 2D corrugated core sandwich panel, the predictions derived by the single layered computational model is generally acceptable when the size of the unit cell varies within a certain range, with the predictions for moderately strong or strong corrugated cores more accurate than those for weak cores.展开更多
Maize chlorotic mottle virus (MCMV) infects maize plants and causes significant losses in corn production worldwide. In this study, purified MCMV particles were used as the immunogen to produce monoclonal antibodies (...Maize chlorotic mottle virus (MCMV) infects maize plants and causes significant losses in corn production worldwide. In this study, purified MCMV particles were used as the immunogen to produce monoclonal antibodies (MAbs) and polyclonal antibodies (PAbs). Four murine MAbs (4B8, 8C11, 6F4, and 9G1) against MCMV were obtained through the hybridoma technology. The triple antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA), dot-immunobinding assay (DIBA), and immunocapture reverse transcription-polymerase chain reaction (IC-RT-PCR) using the MAb 4B8 were then developed for sensitive, specific, and rapid detection of MCMV in fields. MCMV could be detected in infected leaf crude extracts at dilutions of 1:327 680, 1:64000, and 1:3276800 (w/v, g/ml) by TAS-ELISA, DIBA, and IC-RT-PCR, respectively. One hundred and sixty-one maize field samples showing virus-like symptoms and sixty-nine symptomless maize field samples from ten different provinces of China were collected and screened for the presence of MCMV using the established serological methods. A phylogenetic tree was constructed based on the full length CP genes and Chinese MCMV isolates formed one branch with Thailand isolates. The detection results demonstrated that MCMV is one of most prevalent viruses infecting maize in the Yunnan and Sichuan provinces of China.展开更多
文摘AIM:To evaluate the efficacy and safety of the laparoscopic approaches for parastomal hernia repair reported in the literature.METHODS:A systematic review of PubMed and MEDLINE databases was conducted using various combination of the following keywords:stoma repair,laparoscopic,parastomal,and hernia.Case reports,studies with less than 5 patients,and articles not written in English were excluded.Eligible studies were further scrutinized with the 2011 levels of evidence from the Oxford Centre for Evidence-Based Medicine.Two authors reviewed and analyzed each study.If there was any discrepancy between scores,the study in question was referred to another author.A meta-analysis was performed using both random and fixed-effect models.Publication bias was evaluated using Begg's funnel plot and Egger's regression test.The primary outcome analyzed was recurrence of parastomal hernia.Secondary outcomes were mesh infection,surgical site infection,obstruction requiring reoperation,death,and other complications.Studies were grouped by operative technique where indicated.Except for recurrence,most postoperative morbidities were reported for the overall cohort and not by approach so they were analyzed across approach.RESULTS:Fifteen articles with a total of 469 patients were deemed eligible for review.Most postoperative morbidities were reported for the overall cohort,and not by approach.The overall postoperative morbidity rate was 1.8%(95%CI:0.8-3.2),and there was no difference between techniques.The most common postoperative complication was surgical site infection,which was seen in 3.8%(95%CI:2.3-5.7).Infected mesh was observed in 1.7%(95%CI:0.7-3.1),and obstruction requiring reoperation also occurred in 1.7%(95%CI:0.7-3.0).Other complications such as ileus,pneumonia,or urinary tract infection were noted in16.6%(95%CI:11.9-22.1).Eighty-one recurrences were reported overall for a recurrence rate of 17.4%(95%CI:9.5-26.9).The recurrence rate was 10.2%(95%CI:3.9-19.0) for the modified laparoscopic Sugarbaker approach,whereas the
文摘Objective Development of monoclonal antibody based sandwich enzyme linked immunosorbant assay （sELISA） for rapid detection of Salmonella enterica serovar typhi （S. typhi） from food and water samples and optimization of enrichment procedures for use with the developed sELISA to increase the detection sensitivity of the assay. Methods Spleen cells from BALB/c mice immunized with flagellin （H=d） antigen of S. typhi were fused with Sp2/0 myeloma cells. The hybridoma cell line specific to H=d antigen was established, characterized and ascites raised against one of these clones. The hyperimmune serum to flagellin antigen was raised in New Zealand White rabbits. An sELISA was developed using polyclonal antibody as capture and monoclonal antibody as detection antibody. To design the efficient culture strategies for use with the sELISA, different pre-enrichment and enrichment broths were evaluated. The media included buffered peptone water （BPW） and brain heart infusion broth for pre-enrichment and selenite F broth and Rappaport-Vassiliadis broth as enrichment broths. The developed sELISA with preceding enrichment step in BPW （Enrichment-ELISA） was evaluated in various food samples artificially inoculated with S. typhi bacteria. Various food （30） and water （35） samples collected from field were also tested by Enrichment-ELISA and culture method. Results Out of four specific clones to H=d antigen, one clone （# 2/56, IgG2a isotype） was used in sELISA. The sELISA had the detection limit of 10^4-10^5 cfu of S. typhi. Of the various broths used with sELISA, BPW was found to yield maximum ELISA values. Enrichment-ELISA, when tested in artificially inoculated food samples, generally, could detect 10^2 S. typhi cfu/mL within 10 h from various food rinses （meat, vegetable） and milk samples. After overnight enrichment in BPW, as less as 2 bacteria per 10 mL of milk, meat rinse, and chicken rinse could be detected. Only one of the field samples （water） gave false positive result by Enrichment-
基金Supported by the National Basic Research Program of China ("973" Project) (Grant No. 2006CB601202)the National Natural Science Foundation of China (Grant Nos. 10632060,10825210)+1 种基金the National "111" Project of China (Grant No. B06024)the National High-Tech Research and Development Program of China ("863" Project) (Grant No. 2006AA03Z519)
文摘A new type of ultra-lightweight metallic lattice structure (named as the X-type structure) is reported. This periodic structure was formed by two groups of staggered struts in the traditional pyramid structure, and fabricated by folding expanded metal sheet along rows of offset nodes and then brazing the folded structure (as the core) with top and bottom facesheets to form sandwich panels. The out-of-plane compressive and shear properties of the X-type lattice sandwich structure were investigated experimentally and compared to those of the sandwich having a pyramidal truss core. It is found that the formation of the 2-dimensional staggered nodes can effectively make the X-type structure more resistant to inelastic and plastic buckling under both compression and shear loading than the pyramidal lattice truss. Obtained results show that the compressive and shear peak strengths of the X-type lattice structure are about 30% higher than those of the pyramidal lattice truss having the same relative density.
基金China Scholarship CouncilDeutsche Forschungsgemeinschaft,Grant/Award Numbers:LE 2249/4-1,LE 2249/5-1Bundesministerium für Bildung und Forschung,Grant/Award Number:03Z1MN11。
文摘Owing to the high power density,long cycle life and maintain-free,micro-supercapacitors(MSCs)stand out as preferred miniaturized energy source for themiscellaneous autonomous electronic components.However,the shortage of energy density is the main stumbling block for their practical applications.To solve this energy issue,constructing a three-dimensional(3D)electrode within the limited footprint area is proposed as a new solution for improving the energy storage capacity ofMSCs.In the last few years,extensive efforts have been devoted to developing 3D electrodes for MSCs,and significant progress and breakthrough have been achieved.While,there is still lack of systematic summary on the 3D electrode design strategies.To this end,it is imperative to outline the basic design conception,summarize the current states,and discuss the future research about 3D electrodes in MSCs based on the latest development.
基金the financial support from JPTT project (No.JPTT-1146)
文摘This paper presents an experimental study of a novel K-Cor sandwich structure rein- forced with partially-cured Z-pins. The influence of pultrusion processing parameters on Z-pins characteristics was studied and the effect of Z-pins on mechanical properties was disclosed. Differential scanning calorimetry （DSC） and optical microscopy （OM） methods were employed to determine the curing degree of as-prepared Z-pins and observe the implanted Z-pins in the K-Cor structure. These partially-cured Z-pins were treated with a stronger bonding link between face sheets and the foam core by means of a hot-press process, thereby decreasing burrs and cracking defects when the Z-pins were implanted into the Rohacell foam core. The results of the out-of-plane tensile tests and the climbing drum peel （CDP） tests showed that K-Cor structures exhibited superior mechanical performance as compared to X-Cor and blank foam core. The observed results of failure modes revealed that an effective bonding link between the foam core and face sheets that was provided from partially-cured Z-pins contributed to the enhanced mechan- ical performances of K-Cor sandwich structures.
基金supported by the National Key Program for Basic Research(Grant No.R39799N)the National Natural Science Foundation of China.
文摘We report the experimental observations of the segregation patterns in initially well mixed copper and glass spheres subjected to a vertical sinusoidal vibration at differ-ent values of acceleration G and frequency f. A segregation phase diagram is obtained, which includes Brazil nut (BN), Reversed-BN (RBN) and sandwich segregation patterns at different G and f. The stable RBN segregation is experimen-tally found for the first time, in which large heavy particles move down to the bottom and form the lower-layer while small particles rise to the top and form an upper-layer. The boundary values (G, f), which separate regions of different patterns, depend on system’s initial condition, i.e. hysteresis exists.
基金supported by the National Science Foundation of China under grant Nos.90816024 and 10872059the Major State Basic Research Development Program of China (973 Program) under grant No.2006CB601206+1 种基金the Program of Excellent Team inHarbin Institute of Technologythe Program for New Century Excellent Talents in Universityunder grant No.NCET-08-0152
文摘Truss core sandwich panels reinforced by carbon fibers were assembled with bonded laminate facesheets and carbon fiber reinforced truss cores. The top and bottom facesheets were interconnected with truss cores. Both ends of the truss cores were embedded into four layers of top and bottom facesheets. The mechanical properties of truss core sandwich panels were then investigated under out-of-plane and in-plane compression loadings to reveal the failure mechanisms of sandwich panels. Experimental results indicated that the mechanical behavior of sandwich structure under in-plane loading is dominated by the buckling and debonding of facesheets.
基金The project supported by the National Basic Research Program of China(2006CB601202)the National Natural Science Foundation of China(10328203,10572111,10572119,10632060)+2 种基金the National 111 Project of China(B06024),the Program for New Century Excellent Talents in University(NCET-04-0958)the 0pen Foundation of State Key Laboratory of Structural Analysis of Industrial EquipmentDoctorate Foundation of Northwestern Polytechnical University.
文摘An effective single layered finite element （FE） computational model is proposed to predict the structural behavior of lightweight sandwich panels having two dimensional （2D） prismatic or three dimensional （3D） truss cores. Three different types of cellular core topology are considered： pyramidal truss core （3D）, Kagome truss core （3D） and corrugated core （2D）, representing three kinds of material anisotropy： orthotropic, monoclinic and general anisotropic. A homogenization technique is developed to obtain the homogenized macroscopic stiffness properties of the cellular core. In comparison with the results obtained by using detailed FE model, the single layered computational model can give acceptable predictions for both the static and dynamic behaviors of orthotropic truss core sandwich panels. However, for non-orthotropic 3D truss cores, the predictions are not so well. For both static and dynamic behaviors of a 2D corrugated core sandwich panel, the predictions derived by the single layered computational model is generally acceptable when the size of the unit cell varies within a certain range, with the predictions for moderately strong or strong corrugated cores more accurate than those for weak cores.
基金supported by the National Natural Science Foundation of China (No. 31272015)the Ministry of Education of China (No. 313052)the Zhejiang Provincial Natural Science Foundation of China (No. Z3090039)
文摘Maize chlorotic mottle virus (MCMV) infects maize plants and causes significant losses in corn production worldwide. In this study, purified MCMV particles were used as the immunogen to produce monoclonal antibodies (MAbs) and polyclonal antibodies (PAbs). Four murine MAbs (4B8, 8C11, 6F4, and 9G1) against MCMV were obtained through the hybridoma technology. The triple antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA), dot-immunobinding assay (DIBA), and immunocapture reverse transcription-polymerase chain reaction (IC-RT-PCR) using the MAb 4B8 were then developed for sensitive, specific, and rapid detection of MCMV in fields. MCMV could be detected in infected leaf crude extracts at dilutions of 1:327 680, 1:64000, and 1:3276800 (w/v, g/ml) by TAS-ELISA, DIBA, and IC-RT-PCR, respectively. One hundred and sixty-one maize field samples showing virus-like symptoms and sixty-nine symptomless maize field samples from ten different provinces of China were collected and screened for the presence of MCMV using the established serological methods. A phylogenetic tree was constructed based on the full length CP genes and Chinese MCMV isolates formed one branch with Thailand isolates. The detection results demonstrated that MCMV is one of most prevalent viruses infecting maize in the Yunnan and Sichuan provinces of China.
