Zeolite-encapsulated metal nanoclusters are at the heart of bifunctional catalysts,which hold great potential for petrochemical conversion and the emerging sustainable biorefineries.Nevertheless,efficient encapsulatio...Zeolite-encapsulated metal nanoclusters are at the heart of bifunctional catalysts,which hold great potential for petrochemical conversion and the emerging sustainable biorefineries.Nevertheless,efficient encapsulation of metal nanoclusters into a high-silica zeolite Y in particular with good structural integrity still remains a significant challenge.Herein,we have constructed Ru nanoclusters(~1 nm)encapsulated inside a high-silica zeolite Y(SY)with a SiO_(2)/Al_(2)O_(3) ratio(SAR)of 10 via a cooperative strategy for direct zeolite synthesis and a consecutive impregnation for metal encapsulation.Compared with the benchmark Ru/H-USY and other analogues,the as-prepared Ru/H-SY markedly boosts the yields of pentanoic biofuels and stability in the direct hydrodeoxygenation of biomass-derived levulinate even at a mild temperature of 180℃,which are attributed to the notable stabilization of transition states by the enhanced acid accessibility and properly sized constraints of zeolite cavities owing to the good structural integrity.展开更多
In this study, poly(γ-glutamic acid)-coated Fe3 O4 magnetic nanoparticles(γ-PGA/Fe3 O4 MNPs) were successfully fabricated using the co-precipitation method. Fe3 O4 MNPs were also prepared for comparison. The average...In this study, poly(γ-glutamic acid)-coated Fe3 O4 magnetic nanoparticles(γ-PGA/Fe3 O4 MNPs) were successfully fabricated using the co-precipitation method. Fe3 O4 MNPs were also prepared for comparison. The average size and specific surface area results reveal that γ-PGA/Fe3 O4 MNPs(52.4 nm, 88.41 m2·g 1) have smaller particle size and larger specific surface area than Fe3 O4 MNPs(62.0 nm, 76.83 m2·g 1). The γ-PGA/Fe3 O4 MNPs can remove over 99% of Cr3+, Cu2+and Pb2+, and over 77% of Ni2+in deionized water, much higher than γ-PGA and Fe3 O4 MNPs, attributed to the larger specific surface area of γ-PGA/Fe3 O4 MNPs. With the solution pH higher than 6.0, γ-PGA/Fe3 O4 MNPs demonstrate better removal activity. The adsorption isotherm of γ-PGA/Fe3 O4 MNPs for Cr3+fits the Freundlich model well, with the adsorption capacity of 24.60 mg·g 1. γ-PGA/Fe3 O4 MNPs are strongly attracted by permanent magnet, so it is easy to separate them completely from water. With their high efficiency for heavy metal removal and easier separation, γ-PGA/Fe3 O4 MNPs have great potential applications in water treatment.展开更多
A 67-year-old man had a sev-ere cough and pulmonary infection for 1 wk before seeking evaluation at our hospital.He had undergone esophagectomy with gastric pull-up and radiotherapy for esophageal cancer 3 years previ...A 67-year-old man had a sev-ere cough and pulmonary infection for 1 wk before seeking evaluation at our hospital.He had undergone esophagectomy with gastric pull-up and radiotherapy for esophageal cancer 3 years previously.After admission to our hospital,gastroscopy and bronchoscopy revealed a fistulous communication between the posterior tracheal wallnear the carina and the upper residual stomach.We measured the diameter of the trachea and bronchus and determined the site and size of the fistula using multislice computed tomography and gastroscopy.A covered self-expanding Y-shaped metallic stent was implanted into the trachea and bronchus.Subsequently,the fistula was closed completely.The patient tolerated the stent well and had good palliation of his symptoms.展开更多
Y2O3：Eu3＋ phosphors co-doped with different metal cations （Li＋, Na＋, K＋, Mg2＋, Ca2＋） are prepared by the gel- combustion method with Y2O3：Eu3＋, and R（NO3）x （R = Li, Na, K, Mg, Ca） serving as raw materi...Y2O3：Eu3＋ phosphors co-doped with different metal cations （Li＋, Na＋, K＋, Mg2＋, Ca2＋） are prepared by the gel- combustion method with Y2O3：Eu3＋, and R（NO3）x （R = Li, Na, K, Mg, Ca） serving as raw materials and glycine as fuel, calcined at 1000 ℃ for 2 h. The synthesized Y203 ：Eu3＋ phosphors doped with different metal cations and doping ratios are characterized by x-ray diffractometry （XRD）, fluorescence and phosphorescent spectrophotometer. The co-doping metal cations are advantageous to the development of Y203：Eu3＋ lattice. All the samples can emit red light peaked at 611 nm under 254-nm excited. The luminescence intensities of co-doping samples are increased because the cations increase the electron transition probability of Eu3＋ from 5D0 level to 7F level. The fluorescence lifetime of Eu3＋ （SD0 --＋7F2） is increased by doping metal cations.展开更多
Endoscopic intervention is less invasive than percutaneous or surgical approaches and should be considered the primary drainage procedure in most cases with obstructive jaundice.Recently,therapeutic endoscopic retrogr...Endoscopic intervention is less invasive than percutaneous or surgical approaches and should be considered the primary drainage procedure in most cases with obstructive jaundice.Recently,therapeutic endoscopic retrograde cholangiopancreatography(ERCP) using double-balloon enteroscopy(DBE) has been shown to be feasible and effective,even in patients with surgically altered anatomies.On the other hand,endoscopic partial stent-in-stent(PSIS) placement of selfexpandable metallic stents(SEMSs) for malignant hilar biliary obstruction in conventional ERCP has also been shown to be feasible,safe and effective.We performed PSIS placement of SEMSs for malignant hilar biliary obstruction due to liver metastasis using a short DBE in a patient with Roux-en-Y anastomosis and achieved technical and clinical success.This procedure can result in quick relief from obstructive jaundice in a single session and with short-term hospitalization,even in patients with surgically altered anatomies.展开更多
In this communication,we report a synthetic approach to fabricate Y-junction Co nanowires and Y-junction Cu nanowires by AC electrodeposition using a hierarchically designed anodized aluminum oxide template.Morphology...In this communication,we report a synthetic approach to fabricate Y-junction Co nanowires and Y-junction Cu nanowires by AC electrodeposition using a hierarchically designed anodized aluminum oxide template.Morphology study showe that diameters of the stems and branches of the Y-junction nanowires were about 40 nm and 20 nm respectively.Structural analysis indicates that Co nanowires had a mixture of face-center-cubic and hexagonal-close-packed structures,whereas Cu nanowires had a face-center-cubic structure with a <110> texture.The Y-junction Co nanowires exhibited a longitudinal coercivity of 1300 Oe and remnant magnetization of 56%,which was affected by the growth direction and microstructure.The present method can be extended to other metallic systems and thus provides a simple and efficient way to fabricate Y-junction metal nanowires.展开更多
AIM:To describe the variation that divalent metaltransporter 1(DMT1)shows in patients after Rouxen-Y gastric bypass(RYGB)surgery.METHODS:Prospective and analytical study of DMT1level at the brush border of proximal je...AIM:To describe the variation that divalent metaltransporter 1(DMT1)shows in patients after Rouxen-Y gastric bypass(RYGB)surgery.METHODS:Prospective and analytical study of DMT1level at the brush border of proximal jejunum in patients having undergone RYGB surgery.The mucosa of proximal jejunum forming the gastrojejunal anastomosis was biopsied during surgery and after 6 mo later with an endoscopic biopsy.All the patients received precise instructions regarding feeding and nutritional supplementation.Both samples were processed at the same time by immunohistochemistry and western blot.Samples were analysed by a pathologist.For statistical analysis,theχ2 and Wilcoxon tests were used.RESULTS:Sixteen patients were recruited,13 of whom completed the study.Twelve were women.Average age and body mass index(BMI)were 44.1 and 40.4,respectively.Both body weight and BMI decreased significantly during the study period,with an average percent excess weight loss(%EWL)of 60%±13.3%and an average percent excess BMI loss(%EBMIL)of 79.6%±21.6%.Only two patients presented with mild anaemia6 mo after surgery,but their ferritin levels stayed within normal ranges.Staining for DMT1 showed a significant increase in the cytoplasm of enterocytes located at the tips of the villi(χ2=6.03;P=0.049).Nevertheless,the total quantity of DMT1 decreased significantly(Z=2.04;P=0.04).Associated with these results,we observed a significant increase in goblet cells in the villi 6mo postoperatively(Z=-2.47;P=0.013).CONCLUSION:Six months after RYGB surgery,patients exhibit an increase in DMT1 expression in the enterocytes of the tips of the villi at the proximal jejunum.展开更多
The thermal stability and glass-forming ability of Y56-xCexCo20Al24 (x=15, 20, 25, 28, 38, 41, 44) bulk metallic glasses with a diameter of 5 mm were investigated by differential scanning calorimetry and X-ray diffrac...The thermal stability and glass-forming ability of Y56-xCexCo20Al24 (x=15, 20, 25, 28, 38, 41, 44) bulk metallic glasses with a diameter of 5 mm were investigated by differential scanning calorimetry and X-ray diffraction. The results show that the thermal stability of the alloys decreases with the addition of Ce. It has the best glass-forming ability when x=25, whose calculated values can reach about 30 mm in diameter. The effect of Ce element could be explained on the view of Miedema’s theory and elec- tronegativity difference of amorphous alloys.展开更多
The glass forming ability of the [(Fe12/13Y1/13)100?xBx]96Nb2Zr2 (x=9–26) system was investigated using a series of cluster lines. Three types of clusters, an icosahedron (Fe12Y), a capped Archimedes anti-prism (Fe8B...The glass forming ability of the [(Fe12/13Y1/13)100?xBx]96Nb2Zr2 (x=9–26) system was investigated using a series of cluster lines. Three types of clusters, an icosahedron (Fe12Y), a capped Archimedes anti-prism (Fe8B3) and a capped trigonal prism (Fe9B), as well as a binary eutectic (Fe83B17) were considered. Bulk glassy alloy rods of 3 mm in diameter were synthesized using a copper mold suction-casting method. The glass transition temperature was observed for all samples in the boron range of 15.9at%-25.7at%, with the alloy at 15.9at% of boron having the best thermal properties. The ferrous-based bulk metallic glasses (BMG) obtained have high reduced glass transition temperatures with the maximum reaching 0.63 and large supercooled liquid regions with the maximum reaching 111 K. Magnetic testing revealed a large value of coercive force and remanent magnetization, being 11 kA/m and 0.1 T, re- spectively.展开更多
基金supported by the National Natural Science Foundation of China (22288101,21991090,21991091,22078316,22272171 and 22109167)the Sino-French International Research Network (Zeolites)+2 种基金the BL01B1 beamline of SPring-8 and the 1W1B station of Beijing Synchrotron Radiation Facility (BSRF)for the support of XAS measurementsthe Division of Energy Research Resources of Dalian Institute of Chemical Physics for the support of iDPC-STEM measurementsthe support of the Alexander von Humboldt Foundation (CHN 1220532 HFST-P)。
文摘Zeolite-encapsulated metal nanoclusters are at the heart of bifunctional catalysts,which hold great potential for petrochemical conversion and the emerging sustainable biorefineries.Nevertheless,efficient encapsulation of metal nanoclusters into a high-silica zeolite Y in particular with good structural integrity still remains a significant challenge.Herein,we have constructed Ru nanoclusters(~1 nm)encapsulated inside a high-silica zeolite Y(SY)with a SiO_(2)/Al_(2)O_(3) ratio(SAR)of 10 via a cooperative strategy for direct zeolite synthesis and a consecutive impregnation for metal encapsulation.Compared with the benchmark Ru/H-USY and other analogues,the as-prepared Ru/H-SY markedly boosts the yields of pentanoic biofuels and stability in the direct hydrodeoxygenation of biomass-derived levulinate even at a mild temperature of 180℃,which are attributed to the notable stabilization of transition states by the enhanced acid accessibility and properly sized constraints of zeolite cavities owing to the good structural integrity.
基金Supported by the National Natural Science Foundation of China （21276124）, the Research Project of Natural Science for Universities Affiliated to Jiangsu Province （10KJB530002）, Key Projects in the National Science ＆ Technology Pillar Pro-gram （2011BAE07B09-3）, the Jiangsu Provincial Science and Technology Support Program （BE2011831）, and the State High Technology Research and Development Prograr of China （2011AA02A201）.
文摘In this study, poly(γ-glutamic acid)-coated Fe3 O4 magnetic nanoparticles(γ-PGA/Fe3 O4 MNPs) were successfully fabricated using the co-precipitation method. Fe3 O4 MNPs were also prepared for comparison. The average size and specific surface area results reveal that γ-PGA/Fe3 O4 MNPs(52.4 nm, 88.41 m2·g 1) have smaller particle size and larger specific surface area than Fe3 O4 MNPs(62.0 nm, 76.83 m2·g 1). The γ-PGA/Fe3 O4 MNPs can remove over 99% of Cr3+, Cu2+and Pb2+, and over 77% of Ni2+in deionized water, much higher than γ-PGA and Fe3 O4 MNPs, attributed to the larger specific surface area of γ-PGA/Fe3 O4 MNPs. With the solution pH higher than 6.0, γ-PGA/Fe3 O4 MNPs demonstrate better removal activity. The adsorption isotherm of γ-PGA/Fe3 O4 MNPs for Cr3+fits the Freundlich model well, with the adsorption capacity of 24.60 mg·g 1. γ-PGA/Fe3 O4 MNPs are strongly attracted by permanent magnet, so it is easy to separate them completely from water. With their high efficiency for heavy metal removal and easier separation, γ-PGA/Fe3 O4 MNPs have great potential applications in water treatment.
文摘A 67-year-old man had a sev-ere cough and pulmonary infection for 1 wk before seeking evaluation at our hospital.He had undergone esophagectomy with gastric pull-up and radiotherapy for esophageal cancer 3 years previously.After admission to our hospital,gastroscopy and bronchoscopy revealed a fistulous communication between the posterior tracheal wallnear the carina and the upper residual stomach.We measured the diameter of the trachea and bronchus and determined the site and size of the fistula using multislice computed tomography and gastroscopy.A covered self-expanding Y-shaped metallic stent was implanted into the trachea and bronchus.Subsequently,the fistula was closed completely.The patient tolerated the stent well and had good palliation of his symptoms.
文摘Y2O3：Eu3＋ phosphors co-doped with different metal cations （Li＋, Na＋, K＋, Mg2＋, Ca2＋） are prepared by the gel- combustion method with Y2O3：Eu3＋, and R（NO3）x （R = Li, Na, K, Mg, Ca） serving as raw materials and glycine as fuel, calcined at 1000 ℃ for 2 h. The synthesized Y203 ：Eu3＋ phosphors doped with different metal cations and doping ratios are characterized by x-ray diffractometry （XRD）, fluorescence and phosphorescent spectrophotometer. The co-doping metal cations are advantageous to the development of Y203：Eu3＋ lattice. All the samples can emit red light peaked at 611 nm under 254-nm excited. The luminescence intensities of co-doping samples are increased because the cations increase the electron transition probability of Eu3＋ from 5D0 level to 7F level. The fluorescence lifetime of Eu3＋ （SD0 --＋7F2） is increased by doping metal cations.
文摘Endoscopic intervention is less invasive than percutaneous or surgical approaches and should be considered the primary drainage procedure in most cases with obstructive jaundice.Recently,therapeutic endoscopic retrograde cholangiopancreatography(ERCP) using double-balloon enteroscopy(DBE) has been shown to be feasible and effective,even in patients with surgically altered anatomies.On the other hand,endoscopic partial stent-in-stent(PSIS) placement of selfexpandable metallic stents(SEMSs) for malignant hilar biliary obstruction in conventional ERCP has also been shown to be feasible,safe and effective.We performed PSIS placement of SEMSs for malignant hilar biliary obstruction due to liver metastasis using a short DBE in a patient with Roux-en-Y anastomosis and achieved technical and clinical success.This procedure can result in quick relief from obstructive jaundice in a single session and with short-term hospitalization,even in patients with surgically altered anatomies.
基金financially supported partially by a NSF award CMMI-0825990
文摘In this communication,we report a synthetic approach to fabricate Y-junction Co nanowires and Y-junction Cu nanowires by AC electrodeposition using a hierarchically designed anodized aluminum oxide template.Morphology study showe that diameters of the stems and branches of the Y-junction nanowires were about 40 nm and 20 nm respectively.Structural analysis indicates that Co nanowires had a mixture of face-center-cubic and hexagonal-close-packed structures,whereas Cu nanowires had a face-center-cubic structure with a <110> texture.The Y-junction Co nanowires exhibited a longitudinal coercivity of 1300 Oe and remnant magnetization of 56%,which was affected by the growth direction and microstructure.The present method can be extended to other metallic systems and thus provides a simple and efficient way to fabricate Y-junction metal nanowires.
基金Supported by"2009 Clinical and Basic Clinical Research Contest"of the Bureau for Clinical Research Support from the University of Chile Clinical Hospital
文摘AIM:To describe the variation that divalent metaltransporter 1(DMT1)shows in patients after Rouxen-Y gastric bypass(RYGB)surgery.METHODS:Prospective and analytical study of DMT1level at the brush border of proximal jejunum in patients having undergone RYGB surgery.The mucosa of proximal jejunum forming the gastrojejunal anastomosis was biopsied during surgery and after 6 mo later with an endoscopic biopsy.All the patients received precise instructions regarding feeding and nutritional supplementation.Both samples were processed at the same time by immunohistochemistry and western blot.Samples were analysed by a pathologist.For statistical analysis,theχ2 and Wilcoxon tests were used.RESULTS:Sixteen patients were recruited,13 of whom completed the study.Twelve were women.Average age and body mass index(BMI)were 44.1 and 40.4,respectively.Both body weight and BMI decreased significantly during the study period,with an average percent excess weight loss(%EWL)of 60%±13.3%and an average percent excess BMI loss(%EBMIL)of 79.6%±21.6%.Only two patients presented with mild anaemia6 mo after surgery,but their ferritin levels stayed within normal ranges.Staining for DMT1 showed a significant increase in the cytoplasm of enterocytes located at the tips of the villi(χ2=6.03;P=0.049).Nevertheless,the total quantity of DMT1 decreased significantly(Z=2.04;P=0.04).Associated with these results,we observed a significant increase in goblet cells in the villi 6mo postoperatively(Z=-2.47;P=0.013).CONCLUSION:Six months after RYGB surgery,patients exhibit an increase in DMT1 expression in the enterocytes of the tips of the villi at the proximal jejunum.
基金This work was financially supported by the National Natural Science Foundation of China (No.50201009).
文摘The thermal stability and glass-forming ability of Y56-xCexCo20Al24 (x=15, 20, 25, 28, 38, 41, 44) bulk metallic glasses with a diameter of 5 mm were investigated by differential scanning calorimetry and X-ray diffraction. The results show that the thermal stability of the alloys decreases with the addition of Ce. It has the best glass-forming ability when x=25, whose calculated values can reach about 30 mm in diameter. The effect of Ce element could be explained on the view of Miedema’s theory and elec- tronegativity difference of amorphous alloys.
基金This project was financially supported by the National Natural Science Foundation of China (No.50401020, 50671018, 50631010)the Provincial Science and Technology Foundation of Liaoning, China.
文摘The glass forming ability of the [(Fe12/13Y1/13)100?xBx]96Nb2Zr2 (x=9–26) system was investigated using a series of cluster lines. Three types of clusters, an icosahedron (Fe12Y), a capped Archimedes anti-prism (Fe8B3) and a capped trigonal prism (Fe9B), as well as a binary eutectic (Fe83B17) were considered. Bulk glassy alloy rods of 3 mm in diameter were synthesized using a copper mold suction-casting method. The glass transition temperature was observed for all samples in the boron range of 15.9at%-25.7at%, with the alloy at 15.9at% of boron having the best thermal properties. The ferrous-based bulk metallic glasses (BMG) obtained have high reduced glass transition temperatures with the maximum reaching 0.63 and large supercooled liquid regions with the maximum reaching 111 K. Magnetic testing revealed a large value of coercive force and remanent magnetization, being 11 kA/m and 0.1 T, re- spectively.
