The initiation sites and influencing factors of cavity nucleation were investigated for a Ti-6Al-2Zr-1Mo-1V alloy with lamellar starting structure,using the isothermal hot compression test.All samples were deformed to...The initiation sites and influencing factors of cavity nucleation were investigated for a Ti-6Al-2Zr-1Mo-1V alloy with lamellar starting structure,using the isothermal hot compression test.All samples were deformed to a true strain of 0.70 in the temperature range of 750-950°C and strain rate range of 0.001-10 s-1.The corresponding microstructures were observed by means of the metallurgical microscopy and scanning electron microscopy(SEM).It was found that all cavities occurred at the bulge regions of the compression specimens.Most of cavities nucleated along prior beta boundaries oriented 45°to the compression axis,while others nucleated at the interfaces of lamellar alpha colonies.Cavity nucleation was inhibited with increasing the volume fraction of beta phase and the volume fraction spheroidized of lamellar alpha phase.展开更多
AIM: To evaluate the effect of posterior lingual lidocaine swab on patient tolerance to esophagogastro-duodenoscopy, the ease of performance of the procedure, and to determine if such use will reduce the need for intr...AIM: To evaluate the effect of posterior lingual lidocaine swab on patient tolerance to esophagogastro-duodenoscopy, the ease of performance of the procedure, and to determine if such use will reduce the need for intravenous sedation. METHODS: Eighty patients undergoing diagnostic esophagogastroduodenoscopy in a tertiary care medical center were randomized to either lidocaine swab or spray. Intravenous meperidine and midazolam were given as needed during the procedure. RESULTS: Patients in the lidocaine swab group (SWG) tolerated the procedure better than those in the spray group (SPG) with a median tolerability score of 2 (1, 4) compared to 4 (2, 5) (P < 0.01). The endoscopists encountered less diffi culty performing the proceduresin the SWG with lower median difficulty scores of 1 (1, 5) compared to 4 (1, 5) in the SPG (P < 0.01). In addition, the need for intravenous sedation was also lower in the SWG compared to the SPG with fewer patients requiring intravenous sedation (13/40 patients vs 38/40 patients, respectively, P < 0.01). The patients in the SWG were more satisfi ed with the mode of local anesthesia they received as compared to the SPG. In addition, the endoscopists were happier with the use of lidocaine swab. CONCLUSION: The use of a posterior lingual lidocaine swab in esophagogastroduodenoscopy improves patient comfort and tolerance and endoscopist satisfaction and decreases the need for intravenous sedation.展开更多
Mand-Raigarh coalfield is one of the largest coalfields in the Mahanadi basin. The Geological Survey of India carried out initial study primarily on exploration. However, detailed petrographic and geochemical characte...Mand-Raigarh coalfield is one of the largest coalfields in the Mahanadi basin. The Geological Survey of India carried out initial study primarily on exploration. However, detailed petrographic and geochemical characters of the coals have not been done so far. This investigation is an attempt for petrographic and geochemical appraisal of the coals. Moreover, effort is also made for possible interpretation on development of coal facies. The results drawn from 30 composite coal samples suggest coals are rich in vitrinite, with collotelinite as the dominant maceral while liptinite macerals register low concentration. Dominant mineral assemblages found were clay minerals, pyrite was recorded as disseminated, framboidal and euhedral forms, carbonates recorded were mainly siderites. The vitrinite reflectance random （VRo） mean values range from 0.44 % to 0.56 %, and the rank of coal is suggested as high volatile ＇B＇ to ＇A＇ sub- bituminous in rank. The rock-eval pyrolysis reveal TOC content varying from 37 % to 68.83 %, while low hydrocarbon generating potential is evident from low $2 and Tmax values. The Hydrogen Index （HI） versus Oxygen Index （OI） plot reveal that the samples belong to Kerogen type--II-III with input dominantly from terrestrial source, some samples also fall in Kerogen type--II domain indicating lacustrine input. Vitrinite reflectance result indicate that the samples are immature and approaching oil window, which is in agreement with data of the Rock-Eval parameters. The gelification index （GI） and tissue preservation index （TPI） indicate that the coal developed in a telematic set up with high tree density. The ground water index （GWI） and vegetation index （VI） demonstrate that the peat developed as an ombrogenous bog.展开更多
Grout plays an important role in the transmission and maintenance of anchoring force,and in the protection of anchorage materials against corrosion.Thus,the hardening characteristics of grout directly affect the ancho...Grout plays an important role in the transmission and maintenance of anchoring force,and in the protection of anchorage materials against corrosion.Thus,the hardening characteristics of grout directly affect the anchoring effectivity and long-term reliability.We have excavated a prestressed anchorage which has been in service for 20 years,and have tested the grout which has worked for that long period under complicated geological conditions through strength tests and have analyzed its mineral composition using scanning electron microscopy(SEM) and X-ray diffraction(XRD).The results show that the mineral composition of the 12.5 m segment differs from other segments,and corresponds with poor coagulation characteristics of the 12.5 m segment grout.Analysis shows that unhydrated tricalcium silicate may be the reason for the localized poor coagulation.展开更多
A two-dimensional numerical model was used to explain the liquefaction mechanism of double sand lenses and the corresponding soil deformation due to the cyclic loading. Moreover, in order to investigate the influences...A two-dimensional numerical model was used to explain the liquefaction mechanism of double sand lenses and the corresponding soil deformation due to the cyclic loading. Moreover, in order to investigate the influences of the soil characteristics and input loading data a parametric study was carried out on the essential parameters affecting the soil settlement, and so the variation of these parameters with the corresponding displacements was mainly examined. At last, the results obtained from the numerical analyses of double sand lenses and a continuous sand layer with similar characteristics were compared with those of an estimating method proposed by ISHIHARA and YOSHIMINE. The comparisons show that the settlements due to liquefaction of the continuous sand layer in both numerical and the estimating method are in a good agreement with and are obviously greater than those of double sand lenses.展开更多
Indirect extrusion of Mg-10%Sn (mass fraction) alloys was performed at three different working temperatures. The effect of working temperature on the microstructure, texture and tensile properties of the extruded allo...Indirect extrusion of Mg-10%Sn (mass fraction) alloys was performed at three different working temperatures. The effect of working temperature on the microstructure, texture and tensile properties of the extruded alloys was investigated by optical microscope (OM), scanning electronic microscope (SEM), X-ray diffraction (XRD) and a standard universal testing machine. Grain size, area fraction of second phase particles and texture of the alloys are found to be significantly influenced by working temperature. The grain size refinement is greatly dependent on processing conditions with the low working temperature being the most effective. While the high working temperature results in a coarser grain size and a stronger fiber texture and the reason for this phenomenon was examined in terms of second phase particle, grain type and dynamic recrystallization mechanism. Tested in the different conditions, the tensile strengths of the Mg-10Sn alloys extruded at the high working temperature are remarkably better than those of the other studied alloys. This significant improvement in tensile properties is mainly due to the particle strengthening and texture strengthening resulted from the more and finer primary dispersed particles and stronger texture, respectively.展开更多
Based on the techniques of X-ray diffraction analysis, identification of the thin sections of core cast, phys- ical analysis and scanning electron microscopy analysis, this paper studied the reservoir characteristics ...Based on the techniques of X-ray diffraction analysis, identification of the thin sections of core cast, phys- ical analysis and scanning electron microscopy analysis, this paper studied the reservoir characteristics of the Carboniferous strata in Donghe well No.1 of Tarim region. The results show that the reservoir lithology is mainly the fine-grained quartz sandstone with ferrocalcite and pyrite, mud cement-based, the permeability concentrated in 5-40 × 10-3 μm2, a small part of the high permeability up to 150-327 ×10-3 μm2 and porosity ranged from 10% to 20%. The most part of the reservoirs is low perme- ability with a small part of the layer in moderate-high permeability. The types of reservoir space include intergranular pores, intra particle-molding pores, micro-pores and cracks, which mainly are intergranular pores with the pore diameter of 15-200 μm, 95.5μm on average. And the types of the throats are comolex with the main tvne of constricted l：hroats in this area and large contribution to the permeability.展开更多
PU （polyurethane） integral skin and PVC （polyvinyl chloride） are polymeric materials which have favorable physical characteristics to reduce the impact noise when applied to floor systems. In civil construction, f...PU （polyurethane） integral skin and PVC （polyvinyl chloride） are polymeric materials which have favorable physical characteristics to reduce the impact noise when applied to floor systems. In civil construction, floating floors systems are composed of two layers above the slab： a resilient layer and, above this, a rigid layer of cement matrix that works as a subfloor. This research aims to evaluate the incorporation of PVC and PU skin waste in the resilient layer of the floating floor, for impact noise insulation. It was conducted physical, mechanical and morphological tests in the composite, as SEM （scanning electron microscopy）, determination of compressive creep, and impact noise test to evaluate the absorption capacity of the floor system over time. Furthermore, experimental results were compared with theoretical studies. These correlations may assist in understanding the behavior of impact noise damping and its relation to the size of the samples.展开更多
Using optical microscope and scanning electron microscopy （SEM）, revealed the content of pyrite and the microscopic or sub-microscopic occurrence features of pyrite in coal of Huainan. The samples of this study are ...Using optical microscope and scanning electron microscopy （SEM）, revealed the content of pyrite and the microscopic or sub-microscopic occurrence features of pyrite in coal of Huainan. The samples of this study are from four different mines in Huainan coal field. The results show that, in general, the coal of Huainan is low sulfur coal, but the con- tent of pyrite in Guqiao mine is relatively higher. The occurrence types of pyrite in coal mainly include： strawberry ball pyrites, massive pyrites, tuberculoid pyrite and pyrite filling in cracks or joints. After analysis based on three indicating facies parameters IAA, IS and/R, the reason for the higher level of pyrite component is that the deoxidization of swamp wa- ter is stronger, salinity is greater and the hydrodynamic is bad. The strawberry ball pyrites found in Guqiao mostly formed in the syngenesis stage. The spherical raspberry pyrites symbiotic with clay minerals was formed due to the reaction of H2S with Fe in the grid of silicate crystal.展开更多
The aim of this study is to examine and present the results of the scientific examinations carried out on the ground layers with paint samples collected from the decorated surfaces of the wooden coffin dated back to t...The aim of this study is to examine and present the results of the scientific examinations carried out on the ground layers with paint samples collected from the decorated surfaces of the wooden coffin dated back to the late period from Saqqara excavation that belonged to the Ministry of Antiquities. Many analytical methods were performed as optical microscopy, scanning electron microscopy coupled with energy-dispersive X-ray analysis （ESEM-EDX）, X-ray diffraction analysis as well as fourier transform infrared spectroscopy have been used to both characterise the inorganic composition and the binding media used. The analytical results showed that the materials composition and technique used to plaster applied on the wooden surface are in good agreement with the information gathered through the historical survey. The coffin was in bad and poor condition. There was cracking on the surface and in the structure, serious flaking, cupping of some pigments and serious damage in both the wooden support and gesso layer. Conservation treatment processes carried out included consolidation of lifting areas of the paint film, disturbing restoration materials, repair of cracks in the wooden support and a dry surface cleaning of the pigments.展开更多
In the present work, the possibility of existence of spin glass phase using classical Heisenberg model with Edwards-Anderson type of interactions has been explored employing Monte Carlo simulation of Binder parameter ...In the present work, the possibility of existence of spin glass phase using classical Heisenberg model with Edwards-Anderson type of interactions has been explored employing Monte Carlo simulation of Binder parameter （g （L, T））. Previous experimental studies show that there is finite temperature phase transition but this study indicates that there is no finite temperature phase transition in 3D Heisenberg vector spin glass model.展开更多
基金Project(2009ZE56014)supported by the Aeronautical Science Foundation of ChinaProject(gf200901008)supported by the Open Fund of National Defense Key Disciplines Laboratory of Light Alloy Processing Science and Technology,Nanchang Hangkong University,China
文摘The initiation sites and influencing factors of cavity nucleation were investigated for a Ti-6Al-2Zr-1Mo-1V alloy with lamellar starting structure,using the isothermal hot compression test.All samples were deformed to a true strain of 0.70 in the temperature range of 750-950°C and strain rate range of 0.001-10 s-1.The corresponding microstructures were observed by means of the metallurgical microscopy and scanning electron microscopy(SEM).It was found that all cavities occurred at the bulge regions of the compression specimens.Most of cavities nucleated along prior beta boundaries oriented 45°to the compression axis,while others nucleated at the interfaces of lamellar alpha colonies.Cavity nucleation was inhibited with increasing the volume fraction of beta phase and the volume fraction spheroidized of lamellar alpha phase.
文摘AIM: To evaluate the effect of posterior lingual lidocaine swab on patient tolerance to esophagogastro-duodenoscopy, the ease of performance of the procedure, and to determine if such use will reduce the need for intravenous sedation. METHODS: Eighty patients undergoing diagnostic esophagogastroduodenoscopy in a tertiary care medical center were randomized to either lidocaine swab or spray. Intravenous meperidine and midazolam were given as needed during the procedure. RESULTS: Patients in the lidocaine swab group (SWG) tolerated the procedure better than those in the spray group (SPG) with a median tolerability score of 2 (1, 4) compared to 4 (2, 5) (P < 0.01). The endoscopists encountered less diffi culty performing the proceduresin the SWG with lower median difficulty scores of 1 (1, 5) compared to 4 (1, 5) in the SPG (P < 0.01). In addition, the need for intravenous sedation was also lower in the SWG compared to the SPG with fewer patients requiring intravenous sedation (13/40 patients vs 38/40 patients, respectively, P < 0.01). The patients in the SWG were more satisfi ed with the mode of local anesthesia they received as compared to the SPG. In addition, the endoscopists were happier with the use of lidocaine swab. CONCLUSION: The use of a posterior lingual lidocaine swab in esophagogastroduodenoscopy improves patient comfort and tolerance and endoscopist satisfaction and decreases the need for intravenous sedation.
文摘Mand-Raigarh coalfield is one of the largest coalfields in the Mahanadi basin. The Geological Survey of India carried out initial study primarily on exploration. However, detailed petrographic and geochemical characters of the coals have not been done so far. This investigation is an attempt for petrographic and geochemical appraisal of the coals. Moreover, effort is also made for possible interpretation on development of coal facies. The results drawn from 30 composite coal samples suggest coals are rich in vitrinite, with collotelinite as the dominant maceral while liptinite macerals register low concentration. Dominant mineral assemblages found were clay minerals, pyrite was recorded as disseminated, framboidal and euhedral forms, carbonates recorded were mainly siderites. The vitrinite reflectance random （VRo） mean values range from 0.44 % to 0.56 %, and the rank of coal is suggested as high volatile ＇B＇ to ＇A＇ sub- bituminous in rank. The rock-eval pyrolysis reveal TOC content varying from 37 % to 68.83 %, while low hydrocarbon generating potential is evident from low $2 and Tmax values. The Hydrogen Index （HI） versus Oxygen Index （OI） plot reveal that the samples belong to Kerogen type--II-III with input dominantly from terrestrial source, some samples also fall in Kerogen type--II domain indicating lacustrine input. Vitrinite reflectance result indicate that the samples are immature and approaching oil window, which is in agreement with data of the Rock-Eval parameters. The gelification index （GI） and tissue preservation index （TPI） indicate that the coal developed in a telematic set up with high tree density. The ground water index （GWI） and vegetation index （VI） demonstrate that the peat developed as an ombrogenous bog.
基金supported by National Key Technology R&D Program during the 11th Five-Year Plan Perio(Grant NO. 2008BAB29B01)State Key Program of National Natural Science of China(Grant NO. 41130745)Research foundation of the State Key Laboratory of Geohazard Prevention & Geoenvironment Protection (Grant NO.SKLGP2010Z008)
文摘Grout plays an important role in the transmission and maintenance of anchoring force,and in the protection of anchorage materials against corrosion.Thus,the hardening characteristics of grout directly affect the anchoring effectivity and long-term reliability.We have excavated a prestressed anchorage which has been in service for 20 years,and have tested the grout which has worked for that long period under complicated geological conditions through strength tests and have analyzed its mineral composition using scanning electron microscopy(SEM) and X-ray diffraction(XRD).The results show that the mineral composition of the 12.5 m segment differs from other segments,and corresponds with poor coagulation characteristics of the 12.5 m segment grout.Analysis shows that unhydrated tricalcium silicate may be the reason for the localized poor coagulation.
文摘A two-dimensional numerical model was used to explain the liquefaction mechanism of double sand lenses and the corresponding soil deformation due to the cyclic loading. Moreover, in order to investigate the influences of the soil characteristics and input loading data a parametric study was carried out on the essential parameters affecting the soil settlement, and so the variation of these parameters with the corresponding displacements was mainly examined. At last, the results obtained from the numerical analyses of double sand lenses and a continuous sand layer with similar characteristics were compared with those of an estimating method proposed by ISHIHARA and YOSHIMINE. The comparisons show that the settlements due to liquefaction of the continuous sand layer in both numerical and the estimating method are in a good agreement with and are obviously greater than those of double sand lenses.
基金Fo undation item： Proj ect（2012R 1A 1A 1012802） supported by the National Research Foundation of Korea Funded by the Ministry of Education, Science and Technology Project（2013021013-4） supported by Shanxi Province Science Foundation for Youths, China+1 种基金 Project（2012L003） supported by Advanced Programs of Department of Human Resources and Social Security of Shauxi Province for Returned Scholars, China Project supported by Foundation for Young Scholars of Taiyuan University of Technology, China
文摘Indirect extrusion of Mg-10%Sn (mass fraction) alloys was performed at three different working temperatures. The effect of working temperature on the microstructure, texture and tensile properties of the extruded alloys was investigated by optical microscope (OM), scanning electronic microscope (SEM), X-ray diffraction (XRD) and a standard universal testing machine. Grain size, area fraction of second phase particles and texture of the alloys are found to be significantly influenced by working temperature. The grain size refinement is greatly dependent on processing conditions with the low working temperature being the most effective. While the high working temperature results in a coarser grain size and a stronger fiber texture and the reason for this phenomenon was examined in terms of second phase particle, grain type and dynamic recrystallization mechanism. Tested in the different conditions, the tensile strengths of the Mg-10Sn alloys extruded at the high working temperature are remarkably better than those of the other studied alloys. This significant improvement in tensile properties is mainly due to the particle strengthening and texture strengthening resulted from the more and finer primary dispersed particles and stronger texture, respectively.
基金financially supported by the National Major Special Projects of China (No. 2011ZX05005-002-009HZ)the Natural Science Foundation Project of CQ CSTC of China (No. cstc2012jjA90009)+1 种基金the Research Foundation of Chongqing University of Science & Technology of China (Nos. CK20111312, CK2013Z04)the Program of Educational Reform of Chongqing University of Science & Technology of China (No. 201424).
文摘Based on the techniques of X-ray diffraction analysis, identification of the thin sections of core cast, phys- ical analysis and scanning electron microscopy analysis, this paper studied the reservoir characteristics of the Carboniferous strata in Donghe well No.1 of Tarim region. The results show that the reservoir lithology is mainly the fine-grained quartz sandstone with ferrocalcite and pyrite, mud cement-based, the permeability concentrated in 5-40 × 10-3 μm2, a small part of the high permeability up to 150-327 ×10-3 μm2 and porosity ranged from 10% to 20%. The most part of the reservoirs is low perme- ability with a small part of the layer in moderate-high permeability. The types of reservoir space include intergranular pores, intra particle-molding pores, micro-pores and cracks, which mainly are intergranular pores with the pore diameter of 15-200 μm, 95.5μm on average. And the types of the throats are comolex with the main tvne of constricted l：hroats in this area and large contribution to the permeability.
文摘PU （polyurethane） integral skin and PVC （polyvinyl chloride） are polymeric materials which have favorable physical characteristics to reduce the impact noise when applied to floor systems. In civil construction, floating floors systems are composed of two layers above the slab： a resilient layer and, above this, a rigid layer of cement matrix that works as a subfloor. This research aims to evaluate the incorporation of PVC and PU skin waste in the resilient layer of the floating floor, for impact noise insulation. It was conducted physical, mechanical and morphological tests in the composite, as SEM （scanning electron microscopy）, determination of compressive creep, and impact noise test to evaluate the absorption capacity of the floor system over time. Furthermore, experimental results were compared with theoretical studies. These correlations may assist in understanding the behavior of impact noise damping and its relation to the size of the samples.
基金Supported by the National Natural Science Foundation of China(40772092,40972106)
文摘Using optical microscope and scanning electron microscopy （SEM）, revealed the content of pyrite and the microscopic or sub-microscopic occurrence features of pyrite in coal of Huainan. The samples of this study are from four different mines in Huainan coal field. The results show that, in general, the coal of Huainan is low sulfur coal, but the con- tent of pyrite in Guqiao mine is relatively higher. The occurrence types of pyrite in coal mainly include： strawberry ball pyrites, massive pyrites, tuberculoid pyrite and pyrite filling in cracks or joints. After analysis based on three indicating facies parameters IAA, IS and/R, the reason for the higher level of pyrite component is that the deoxidization of swamp wa- ter is stronger, salinity is greater and the hydrodynamic is bad. The strawberry ball pyrites found in Guqiao mostly formed in the syngenesis stage. The spherical raspberry pyrites symbiotic with clay minerals was formed due to the reaction of H2S with Fe in the grid of silicate crystal.
文摘The aim of this study is to examine and present the results of the scientific examinations carried out on the ground layers with paint samples collected from the decorated surfaces of the wooden coffin dated back to the late period from Saqqara excavation that belonged to the Ministry of Antiquities. Many analytical methods were performed as optical microscopy, scanning electron microscopy coupled with energy-dispersive X-ray analysis （ESEM-EDX）, X-ray diffraction analysis as well as fourier transform infrared spectroscopy have been used to both characterise the inorganic composition and the binding media used. The analytical results showed that the materials composition and technique used to plaster applied on the wooden surface are in good agreement with the information gathered through the historical survey. The coffin was in bad and poor condition. There was cracking on the surface and in the structure, serious flaking, cupping of some pigments and serious damage in both the wooden support and gesso layer. Conservation treatment processes carried out included consolidation of lifting areas of the paint film, disturbing restoration materials, repair of cracks in the wooden support and a dry surface cleaning of the pigments.
文摘In the present work, the possibility of existence of spin glass phase using classical Heisenberg model with Edwards-Anderson type of interactions has been explored employing Monte Carlo simulation of Binder parameter （g （L, T））. Previous experimental studies show that there is finite temperature phase transition but this study indicates that there is no finite temperature phase transition in 3D Heisenberg vector spin glass model.
