BACKGROUND Primary squamous cell carcinoma(SCC)of the renal parenchyma is extremely rare,with only nine cases reported.CASE SUMMARY This study reports a 51-year-old man with primary SCC of the renal parenchyma.The pat...BACKGROUND Primary squamous cell carcinoma(SCC)of the renal parenchyma is extremely rare,with only nine cases reported.CASE SUMMARY This study reports a 51-year-old man with primary SCC of the renal parenchyma.The patient was admitted with recurrent dull pain and discomfort in the right lumbar region,which had worsened over 2 weeks,accompanied by painful gross hematuria.SCC antigen(SCCA)levels were elevated,and imaging revealed a renal mass with associated calculi.The patient underwent laparoscopic unilateral nephrectomy and lymph node dissection.Postoperative pathology confirmed highly differentiated SCC with necrosis in the right renal parenchyma,with negative renal pelvis and ureter.The pathological stage was Pt3aN1M0.Four months after surgery,the tumor recurred with involvement of the liver,right psoas major muscle,and inferior vena cava.The patient refused chemotherapy and succumbed to the disease 6 months postoperatively due to disease progression.CONCLUSION We report a case of primary SCC of the renal parenchyma,a rare renal malignancy.The clinical symptoms,laboratory tests,and imaging findings are nonspecific,making accurate and timely diagnosis challenging.According to the literature,for patients with renal calculi accompanied by a renal mass,elevated serum SCCA levels,and magnetic resonance imaging showing cystic or cystic-solid masses within the kidney with pseudocapsules and heterogeneous mild enhancement,the possibility of this disease should be considered.展开更多
Background Dental implants have been widely used in the last few decades.However,patients with insufficient bone height need reconstructive surgeries before implant insertion.Distraction implant(Dl)has been invented t...Background Dental implants have been widely used in the last few decades.However,patients with insufficient bone height need reconstructive surgeries before implant insertion.Distraction implant(Dl)has been invented to simplify the treatment procedure,but the shortcomings of Dl have limited its clinical use.We introduced biodegradable polyester to a novel Dl,called biodegradable interference distraction implant(BIDI).The purpose of this study was to assess the radiological,histological,and biomechanical properties of BIDI in animal models.Methods BIDIs were manufactured and inserted into the atrophied mandibles of 6 dogs.展开更多
Relative seismic velocity change(dv/v)is important for monitoring changes in subsurface material properties and evaluating earthquake-induced rock slope damage in a geological disaster-prone region.In this paper,we pr...Relative seismic velocity change(dv/v)is important for monitoring changes in subsurface material properties and evaluating earthquake-induced rock slope damage in a geological disaster-prone region.In this paper,we present a rapid damage assessment on three slow-moving rock slopes by measuring dv/v decrease caused by the 2022 M_(S) 6.8 Luding earthquake in Southwest China.By applying the stretching method to the cross-correlated seismic wavefields between sensors installed on each slope,we obtain earthquake-induced dv/v decreases of~2.1%,~0.5%,and~0.2%on three slopes at distances ranging from~86 to~370 km to the epicenter,respectively.Moreover,based on seismic data recorded by 16 sensors deployed on the rock slope at a distance of~370 km away from the epicenter,a localized dv/v decease region was observed at the crest of the slope by calculating the spatial dv/v images before and after the earthquake.We also derive an empirical in situ stress sensitivity of -7.29×10^(-8)/Pa by relating the dv/v change to the measured peak dynamic stresses.Our results indicate that a rapid dv/v assessment not only can help facilitate on-site emergency response to earthquakeinduced secondary geological disasters but also can provide a better understanding of the subsurface geological risks under diverse seismic loadings.展开更多
Numerical simulation and experiments were introduced to develop AA4045/AA3003 cladding billets with different clad-ratios. The temperature fields, microstructures and mechanical properties near interface were investig...Numerical simulation and experiments were introduced to develop AA4045/AA3003 cladding billets with different clad-ratios. The temperature fields, microstructures and mechanical properties near interface were investigated in detail. The results show that cladding billets with different clad-ratios were fabricated successfully. Si and Mn elements diffused across the bonding interface and formed diffusion layer. With the increase of clad-layer thickness, the interfacial region transforms from semisolid-solid state to liquid-solid state and the diffusion layer increased from 10 to 25 μm. The hardness at interface is higher than that of AA3003 side but lower than that of the other side. The bonding strength increased with the clad-layer thickness, attributing to solution strengthening due to elements diffusion. The cladding billets were extruded into clad pipe by indirect extrusion process after homogenization. The clad pipe remained the interfacial characteristics of as-cast cladding billet and the heredity of clad-ratio during deformation was testified.展开更多
Objective To estimate the biological exposure limit （BEL） using benchmark dose （BMD） based on two sets of data from occupational epidemiology. Methods Cadmium-exposed workers were selected from a cadmium smelting ...Objective To estimate the biological exposure limit （BEL） using benchmark dose （BMD） based on two sets of data from occupational epidemiology. Methods Cadmium-exposed workers were selected from a cadmium smelting factory and a zinc product factory. Doctors, nurses or shop assistants living in the same area served as a control group. Urinary cadmium （UCd） was used as an exposure biomarker and urinary D2-microgloburin （B2M）, N-acetyl-D-D-glucosaminidase （NAG） and albumin （ALB） as effect biomarkers. All urine parameters were adjusted by urinary creatinine. Software of BMDS （Version 1.3.2, EPA.U.S.A） was used to calculate BMD. Results The cut-off point （abnormal values） was determined based on the upper limit of 95% of effect biomarkers in control group. There was a significant dose response relationship between the effect biomarkers （urinary B2M, NAG9 and ALB） and exposure biomarker （UCd）. BEL value was 5 μg/g creatinine for UB2M as an effect biomarker, consistent with the recommendation of WHO. BEL could be estimated by using the method of BMD. BEL value was 3 μg/g creafinine for UNAG as an effect biomarker. The more sensitive the used biomarker is, the more occupational population will be protected. Conclusion BMD can be used in estimating the biological exposure limit （BEL）. UNAG is a sensitive biomarker for estimating BEL after cadmium exposure.展开更多
The Qian-Gorlos earthquake, which occurred in the Songliao basin in Jilin Province in 1119 AD, was the largest earthquake to occur in NE China before the 1975 Haicheng earthquake. Based on historical records and surfa...The Qian-Gorlos earthquake, which occurred in the Songliao basin in Jilin Province in 1119 AD, was the largest earthquake to occur in NE China before the 1975 Haicheng earthquake. Based on historical records and surface geological investigations, it has been suggested previously that the earthquake epicenter was in the Longkeng area. However, other workers have considered the epicenter to be in the Halamaodu area based on the landslides and faults found in this region. No seismogenic structure has yet been found in either of these two regions.We tried to detect active faults in the urban areas of Songyuan City, where the historical earthquake was probably located. One of the aims of this work was to clarify the seismogenic structure so that the seismic risk in the city could be more accurately evaluated. The area was investigated and analyzed using information from remote sensing and topographic surveys, seismic data from petroleum exploration, shallow seismic profiles, exploratory geological trenches on fault outcrops, and borehole data. The geophysical data did not reveal any evidence of faults cutting through Cretaceous or later strata under the Longkeng scarp, which has been suggested to be structural evidence of the Qian-Gorlos earthquake. The continuous fault surfaces on the back edge of terraces in theHalamaodu area stretch for [3.5 km and were probably formed by tectonic activity. However, results from shallow seismic profiles showed that the faults did not extend downward, with the corresponding deep structure being identified as a gentle kink band. A new reverse fault was found to the west of the two suggested epicenters, which presented as a curvilinear fault extending to the west, and was formed by two groups of NE- and NW-trending faults intersecting the Gudian fault. Three-dimensional seismic and shallow seismic data from petroleum exploration revealed its distinct spatial distribution and showed that the fault may cut through Late Quaternary strata. Exploration boreholes and later geomorphological studies provided further proof of this. Based on these results and analysis,the Gudian fault was confirmed as having been an active fault since the Late Quaternary, with the possibility of earthquakes of magnitude [7 in the future. The QianGorlos earthquake was most probably the result of breakage on one or two sections of this 66-km-long fault.展开更多
Design and synthesis of low cost and efficacious industrial catalyst for the oxidation of styrene has been an important research project.Herein,ZSM-5 zeolite containing tetrahedral vanadium(V)and Br?nsted acid sites(V...Design and synthesis of low cost and efficacious industrial catalyst for the oxidation of styrene has been an important research project.Herein,ZSM-5 zeolite containing tetrahedral vanadium(V)and Br?nsted acid sites(V-H-ZSM-5)was prepared,and identified by characterizations such as XRD,SEM,UV–vis,NH3-TPD,H2-TPR N2-adsorption/desorption and FTIR.V-H-ZSM-5 performed extremely enhanced catalytic activity for the oxidation of styrene with 30%H2O2 at 40°C.Moreover,in-situ FTIR spectrum was used to investigate the catalytic mechanism.The results demonstrate that Br?nsted acid site could not only increase the adsorption concentration of styrene in the micropores of V-H-ZSM-5 via theπcomplex interaction between double bond of styrene and Br?nsted acid sites,but also increase the oxidation potential of H2O2.The synergetic action of tetrahedral vanadium(V)and Br?nsted acid enhanced the catalytic activity for the oxidation of styrene with 30%H2O2.Impressively,V-H-ZSM-5 performed high reusability within five runs at a low reaction temperature(40°C)for the first time.展开更多
Opening the silicon oxide mask of a capacitor in dynamic random access memory is a critical process on a capacitive coupled plasma(CCP)etch tool.Three steps,dielectric anti-reflective coating(DARC)etch back,silicon ox...Opening the silicon oxide mask of a capacitor in dynamic random access memory is a critical process on a capacitive coupled plasma(CCP)etch tool.Three steps,dielectric anti-reflective coating(DARC)etch back,silicon oxide etch and strip,are contained.To acquire good performance,such as low leakage current and high capacitance,for further fabricating capacitors,we should firstly optimize DARC etch back.We developed some experiments,focusing on etch time and chemistry,to evalu-ate the profile of a silicon oxide mask,DARC remain and critical dimension.The result shows that etch back time should be con-trolled in the range from 50 to 60 s,based on the current equipment and condition.It will make B/T ratio higher than 70%mean-while resolve the DARC remain issue.We also found that CH_(2)F_(2) flow should be~15 sccm to avoid reversed CD trend and keep in-line CD.展开更多
A low-clad-ratio AA4045/AA3003 cladding billet was fabricated using a semi-continuous casting process and was subsequently extruded indirectly into a cladding pipe. The temperature distribution near the interface was ...A low-clad-ratio AA4045/AA3003 cladding billet was fabricated using a semi-continuous casting process and was subsequently extruded indirectly into a cladding pipe. The temperature distribution near the interface was measured. The microstructures, elemental distribution, Vickers hardness around the bonding interface, and the interfacial shear strength were examined. The results showed that the interface temperature rebounded when AA4045 melt contacted the supporting layer. The two alloys bonded well, with few defects, via the diffusion of Si and Mn in the temperature range from 569℃ to 632℃. The mean shear strength of the bonding interface was 82.3 MPa, which was greater than that of AA3003（75.8 MPa）, indicating that the two alloys bonded with each other metallurgically via elemental interdiffusion. Moreover, no relative slip occurred between the two alloys during the extrusion process.展开更多
We have studied the characteristics of the active faults and seismicity in the vicinity of Urumqi city, the capital of Xinjiang Autonomous Region, China, and have proposed a seismogenic model for the assessment of ear...We have studied the characteristics of the active faults and seismicity in the vicinity of Urumqi city, the capital of Xinjiang Autonomous Region, China, and have proposed a seismogenic model for the assessment of earthquake hazard in this area. Our work is based on an integrated analysis of data from investigations of active faults at the surface, deep seismic reflection soundings, seismic profiles from petroleum exploration, observations of temporal seismic stations, and the precise location of small earthquakes. We have made a comparative study of typical seismogenic structures in the frontal area of the North Tianshan Mountains, where Urumqi city is situated, and have revealed the primary features of the thrust-fold- nappe structure there. We suggest that Urumqi city is comprised two zones of seismotectonics which are inter- preted as thrust-nappe structures. The first is the thrust nappe of the North Tianshan Mountains in the west, con- sisting of the lower （root） thrust fault, middle detachment, and upper fold-uplift at the front. Faults active in the Pleistocene are present in the lower and upper parts of this structure, and the detachment in the middle spreads toward the north. In the future, M7 earthquakes may occur at the root thrust fault, while the seismic risk of frontal fold-uplift at the front will not exceed M6.5. The second structure is the western flank of the arc-like Bogda nappe in the east, which is also comprised a root thrust fault, middle detachment, and upper fold-uplift at the front, of which the nappe stretches toward the north; several active faults are also developed in it. The fault active in the Holocene is called the South Fukang fault. It is not in the urban area of Urumqi city. The other three faults are located in the urban area and were active in the late Pleistocene. In these cases, this section of the nappe structure near the city has an earthquake risk of M6.5-7, An earthquake Ms6.6, 60 km east to Urumqi city occurred along the structure in 1965.展开更多
Interfacial solar-steam generation is a promising and cost-effective technology for both desalination and wastewater treatment.This process uses a photothermal evaporator to absorb sunlight and convert it into heat fo...Interfacial solar-steam generation is a promising and cost-effective technology for both desalination and wastewater treatment.This process uses a photothermal evaporator to absorb sunlight and convert it into heat for water evaporation.However solar-steam generation can be somewhat inefficient due to energy losses via conduction,convection and radiation.Thus,efficient energy management is crucial for optimizing the performance of solar-steam generation.Here,via elaborate design of the configuration of photothermal materials,as well as warm and cold evaporation surfaces,performance in solar evaporation was significantly enhanced.This was achieved via a simultaneous reduction in energy loss with a net increase in energy gain from the environment,and recycling of the latent heat released from vapor condensation,diffusive reflectance,thermal radiation and convection from the evaporation surface.Overall,by using the new strategy,an evaporation rate of 2.94 kg m^-2 h^-1,with a corresponding energy efficiency of solar-steam generation beyond theoretical limit was achieved.展开更多
The development of a dual-frequency multi-constellation satellite-based augmentation system(DFMC SBAS)is in progress worldwide.The broadcasted dual-frequency range error(DFRE)integrity parameter reflects the effects o...The development of a dual-frequency multi-constellation satellite-based augmentation system(DFMC SBAS)is in progress worldwide.The broadcasted dual-frequency range error(DFRE)integrity parameter reflects the effects of satellite ephemeris and clock corrections.A user uses the DFRE to calculate the protection level and then determines whether the DFMC SBAS service satisfies the requirements of the current flight phase.However,the calculation of the DFRE has not been reported.Herein,a DFRE estimation method is proposed based on the projection method.Using the ephemeris-clock covariance matrix of each satellite,the maximal projection direction was solved,and the projection of the covariance matrix on this direction was used as the DFRE to form an envelope for the maximal corrected error.Results show that the DFRE can form an envelope of the maximal corrected error with a set probability,and the integrity performance in the user segment satisfies the Category I precision approach requirement.展开更多
文摘BACKGROUND Primary squamous cell carcinoma(SCC)of the renal parenchyma is extremely rare,with only nine cases reported.CASE SUMMARY This study reports a 51-year-old man with primary SCC of the renal parenchyma.The patient was admitted with recurrent dull pain and discomfort in the right lumbar region,which had worsened over 2 weeks,accompanied by painful gross hematuria.SCC antigen(SCCA)levels were elevated,and imaging revealed a renal mass with associated calculi.The patient underwent laparoscopic unilateral nephrectomy and lymph node dissection.Postoperative pathology confirmed highly differentiated SCC with necrosis in the right renal parenchyma,with negative renal pelvis and ureter.The pathological stage was Pt3aN1M0.Four months after surgery,the tumor recurred with involvement of the liver,right psoas major muscle,and inferior vena cava.The patient refused chemotherapy and succumbed to the disease 6 months postoperatively due to disease progression.CONCLUSION We report a case of primary SCC of the renal parenchyma,a rare renal malignancy.The clinical symptoms,laboratory tests,and imaging findings are nonspecific,making accurate and timely diagnosis challenging.According to the literature,for patients with renal calculi accompanied by a renal mass,elevated serum SCCA levels,and magnetic resonance imaging showing cystic or cystic-solid masses within the kidney with pseudocapsules and heterogeneous mild enhancement,the possibility of this disease should be considered.
基金supported by the National Natural Science Foundation of China(No. 30900284,No.31100668,and No.31070873)
文摘Background Dental implants have been widely used in the last few decades.However,patients with insufficient bone height need reconstructive surgeries before implant insertion.Distraction implant(Dl)has been invented to simplify the treatment procedure,but the shortcomings of Dl have limited its clinical use.We introduced biodegradable polyester to a novel Dl,called biodegradable interference distraction implant(BIDI).The purpose of this study was to assess the radiological,histological,and biomechanical properties of BIDI in animal models.Methods BIDIs were manufactured and inserted into the atrophied mandibles of 6 dogs.
基金the National Science Foundation of China(Grant No.NSFC4187406142120104002)the Central Research Institutes of Basic Research and Public Service Special Operations(Grant No.DQJB22Z02).
文摘Relative seismic velocity change(dv/v)is important for monitoring changes in subsurface material properties and evaluating earthquake-induced rock slope damage in a geological disaster-prone region.In this paper,we present a rapid damage assessment on three slow-moving rock slopes by measuring dv/v decrease caused by the 2022 M_(S) 6.8 Luding earthquake in Southwest China.By applying the stretching method to the cross-correlated seismic wavefields between sensors installed on each slope,we obtain earthquake-induced dv/v decreases of~2.1%,~0.5%,and~0.2%on three slopes at distances ranging from~86 to~370 km to the epicenter,respectively.Moreover,based on seismic data recorded by 16 sensors deployed on the rock slope at a distance of~370 km away from the epicenter,a localized dv/v decease region was observed at the crest of the slope by calculating the spatial dv/v images before and after the earthquake.We also derive an empirical in situ stress sensitivity of -7.29×10^(-8)/Pa by relating the dv/v change to the measured peak dynamic stresses.Our results indicate that a rapid dv/v assessment not only can help facilitate on-site emergency response to earthquakeinduced secondary geological disasters but also can provide a better understanding of the subsurface geological risks under diverse seismic loadings.
基金Project(2015B090926013)supported by the Science and Technology Program of Guangdong Province,ChinaProject(20170540307)supported by the Natural Science Foundation of Liaoning Province,China
文摘Numerical simulation and experiments were introduced to develop AA4045/AA3003 cladding billets with different clad-ratios. The temperature fields, microstructures and mechanical properties near interface were investigated in detail. The results show that cladding billets with different clad-ratios were fabricated successfully. Si and Mn elements diffused across the bonding interface and formed diffusion layer. With the increase of clad-layer thickness, the interfacial region transforms from semisolid-solid state to liquid-solid state and the diffusion layer increased from 10 to 25 μm. The hardness at interface is higher than that of AA3003 side but lower than that of the other side. The bonding strength increased with the clad-layer thickness, attributing to solution strengthening due to elements diffusion. The cladding billets were extruded into clad pipe by indirect extrusion process after homogenization. The clad pipe remained the interfacial characteristics of as-cast cladding billet and the heredity of clad-ratio during deformation was testified.
文摘Objective To estimate the biological exposure limit （BEL） using benchmark dose （BMD） based on two sets of data from occupational epidemiology. Methods Cadmium-exposed workers were selected from a cadmium smelting factory and a zinc product factory. Doctors, nurses or shop assistants living in the same area served as a control group. Urinary cadmium （UCd） was used as an exposure biomarker and urinary D2-microgloburin （B2M）, N-acetyl-D-D-glucosaminidase （NAG） and albumin （ALB） as effect biomarkers. All urine parameters were adjusted by urinary creatinine. Software of BMDS （Version 1.3.2, EPA.U.S.A） was used to calculate BMD. Results The cut-off point （abnormal values） was determined based on the upper limit of 95% of effect biomarkers in control group. There was a significant dose response relationship between the effect biomarkers （urinary B2M, NAG9 and ALB） and exposure biomarker （UCd）. BEL value was 5 μg/g creatinine for UB2M as an effect biomarker, consistent with the recommendation of WHO. BEL could be estimated by using the method of BMD. BEL value was 3 μg/g creafinine for UNAG as an effect biomarker. The more sensitive the used biomarker is, the more occupational population will be protected. Conclusion BMD can be used in estimating the biological exposure limit （BEL）. UNAG is a sensitive biomarker for estimating BEL after cadmium exposure.
基金supported by the National Natural Science Foundation of China under Grant No.41372216the Major Projects of the Ministry of Finance under Grant No.201108001+1 种基金the Fundamental Research Funds of the Central Universities under Grant No.20120102 and No.ZY20150303the Teachers Fund of China Earthquake Administration under Grant No.2012001
文摘The Qian-Gorlos earthquake, which occurred in the Songliao basin in Jilin Province in 1119 AD, was the largest earthquake to occur in NE China before the 1975 Haicheng earthquake. Based on historical records and surface geological investigations, it has been suggested previously that the earthquake epicenter was in the Longkeng area. However, other workers have considered the epicenter to be in the Halamaodu area based on the landslides and faults found in this region. No seismogenic structure has yet been found in either of these two regions.We tried to detect active faults in the urban areas of Songyuan City, where the historical earthquake was probably located. One of the aims of this work was to clarify the seismogenic structure so that the seismic risk in the city could be more accurately evaluated. The area was investigated and analyzed using information from remote sensing and topographic surveys, seismic data from petroleum exploration, shallow seismic profiles, exploratory geological trenches on fault outcrops, and borehole data. The geophysical data did not reveal any evidence of faults cutting through Cretaceous or later strata under the Longkeng scarp, which has been suggested to be structural evidence of the Qian-Gorlos earthquake. The continuous fault surfaces on the back edge of terraces in theHalamaodu area stretch for [3.5 km and were probably formed by tectonic activity. However, results from shallow seismic profiles showed that the faults did not extend downward, with the corresponding deep structure being identified as a gentle kink band. A new reverse fault was found to the west of the two suggested epicenters, which presented as a curvilinear fault extending to the west, and was formed by two groups of NE- and NW-trending faults intersecting the Gudian fault. Three-dimensional seismic and shallow seismic data from petroleum exploration revealed its distinct spatial distribution and showed that the fault may cut through Late Quaternary strata. Exploration boreholes and later geomorphological studies provided further proof of this. Based on these results and analysis,the Gudian fault was confirmed as having been an active fault since the Late Quaternary, with the possibility of earthquakes of magnitude [7 in the future. The QianGorlos earthquake was most probably the result of breakage on one or two sections of this 66-km-long fault.
基金supported by the National Natural Science Foundation of China(Nos.21476108,21276125,21776129,21706121 and 21908085)Natural Science Foundation of Jiangsu Province(Nos.BK20170995 and BK20190961)+1 种基金General Program for University Natural Science Research of Jiangsu Province(No.16KJB530003)the Project of Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Design and synthesis of low cost and efficacious industrial catalyst for the oxidation of styrene has been an important research project.Herein,ZSM-5 zeolite containing tetrahedral vanadium(V)and Br?nsted acid sites(V-H-ZSM-5)was prepared,and identified by characterizations such as XRD,SEM,UV–vis,NH3-TPD,H2-TPR N2-adsorption/desorption and FTIR.V-H-ZSM-5 performed extremely enhanced catalytic activity for the oxidation of styrene with 30%H2O2 at 40°C.Moreover,in-situ FTIR spectrum was used to investigate the catalytic mechanism.The results demonstrate that Br?nsted acid site could not only increase the adsorption concentration of styrene in the micropores of V-H-ZSM-5 via theπcomplex interaction between double bond of styrene and Br?nsted acid sites,but also increase the oxidation potential of H2O2.The synergetic action of tetrahedral vanadium(V)and Br?nsted acid enhanced the catalytic activity for the oxidation of styrene with 30%H2O2.Impressively,V-H-ZSM-5 performed high reusability within five runs at a low reaction temperature(40°C)for the first time.
文摘Opening the silicon oxide mask of a capacitor in dynamic random access memory is a critical process on a capacitive coupled plasma(CCP)etch tool.Three steps,dielectric anti-reflective coating(DARC)etch back,silicon oxide etch and strip,are contained.To acquire good performance,such as low leakage current and high capacitance,for further fabricating capacitors,we should firstly optimize DARC etch back.We developed some experiments,focusing on etch time and chemistry,to evalu-ate the profile of a silicon oxide mask,DARC remain and critical dimension.The result shows that etch back time should be con-trolled in the range from 50 to 60 s,based on the current equipment and condition.It will make B/T ratio higher than 70%mean-while resolve the DARC remain issue.We also found that CH_(2)F_(2) flow should be~15 sccm to avoid reversed CD trend and keep in-line CD.
基金the support of the Science and Technology Program of Guangzhou, China (No.2015B090926013)the doctoral foundation of the China Ministry of Education (No.20130042130001)
文摘A low-clad-ratio AA4045/AA3003 cladding billet was fabricated using a semi-continuous casting process and was subsequently extruded indirectly into a cladding pipe. The temperature distribution near the interface was measured. The microstructures, elemental distribution, Vickers hardness around the bonding interface, and the interfacial shear strength were examined. The results showed that the interface temperature rebounded when AA4045 melt contacted the supporting layer. The two alloys bonded well, with few defects, via the diffusion of Si and Mn in the temperature range from 569℃ to 632℃. The mean shear strength of the bonding interface was 82.3 MPa, which was greater than that of AA3003（75.8 MPa）, indicating that the two alloys bonded with each other metallurgically via elemental interdiffusion. Moreover, no relative slip occurred between the two alloys during the extrusion process.
基金supported by Teachers Fund of China Earthquake Administration under Grant No. 20120101National Natural Science Foundation of China under Grant No. 41372216+1 种基金the State Special Project for International Cooperation on Science and Technology 2012DFR20440K02the Fundamental Research Funds for the Central Universities under Grant No. ZY20120102
文摘We have studied the characteristics of the active faults and seismicity in the vicinity of Urumqi city, the capital of Xinjiang Autonomous Region, China, and have proposed a seismogenic model for the assessment of earthquake hazard in this area. Our work is based on an integrated analysis of data from investigations of active faults at the surface, deep seismic reflection soundings, seismic profiles from petroleum exploration, observations of temporal seismic stations, and the precise location of small earthquakes. We have made a comparative study of typical seismogenic structures in the frontal area of the North Tianshan Mountains, where Urumqi city is situated, and have revealed the primary features of the thrust-fold- nappe structure there. We suggest that Urumqi city is comprised two zones of seismotectonics which are inter- preted as thrust-nappe structures. The first is the thrust nappe of the North Tianshan Mountains in the west, con- sisting of the lower （root） thrust fault, middle detachment, and upper fold-uplift at the front. Faults active in the Pleistocene are present in the lower and upper parts of this structure, and the detachment in the middle spreads toward the north. In the future, M7 earthquakes may occur at the root thrust fault, while the seismic risk of frontal fold-uplift at the front will not exceed M6.5. The second structure is the western flank of the arc-like Bogda nappe in the east, which is also comprised a root thrust fault, middle detachment, and upper fold-uplift at the front, of which the nappe stretches toward the north; several active faults are also developed in it. The fault active in the Holocene is called the South Fukang fault. It is not in the urban area of Urumqi city. The other three faults are located in the urban area and were active in the late Pleistocene. In these cases, this section of the nappe structure near the city has an earthquake risk of M6.5-7, An earthquake Ms6.6, 60 km east to Urumqi city occurred along the structure in 1965.
基金financial support from Australian Research Council(ARC Future Fellowship FT190100485)University of South Australia(Foundation Fellow)China Scholarship Council and Huasheng Graphite Co.,Ltd。
文摘Interfacial solar-steam generation is a promising and cost-effective technology for both desalination and wastewater treatment.This process uses a photothermal evaporator to absorb sunlight and convert it into heat for water evaporation.However solar-steam generation can be somewhat inefficient due to energy losses via conduction,convection and radiation.Thus,efficient energy management is crucial for optimizing the performance of solar-steam generation.Here,via elaborate design of the configuration of photothermal materials,as well as warm and cold evaporation surfaces,performance in solar evaporation was significantly enhanced.This was achieved via a simultaneous reduction in energy loss with a net increase in energy gain from the environment,and recycling of the latent heat released from vapor condensation,diffusive reflectance,thermal radiation and convection from the evaporation surface.Overall,by using the new strategy,an evaporation rate of 2.94 kg m^-2 h^-1,with a corresponding energy efficiency of solar-steam generation beyond theoretical limit was achieved.
基金the State Key Laboratory of Geo-Information Engineering,No.SKLGIE2018-Z-2-2.
文摘The development of a dual-frequency multi-constellation satellite-based augmentation system(DFMC SBAS)is in progress worldwide.The broadcasted dual-frequency range error(DFRE)integrity parameter reflects the effects of satellite ephemeris and clock corrections.A user uses the DFRE to calculate the protection level and then determines whether the DFMC SBAS service satisfies the requirements of the current flight phase.However,the calculation of the DFRE has not been reported.Herein,a DFRE estimation method is proposed based on the projection method.Using the ephemeris-clock covariance matrix of each satellite,the maximal projection direction was solved,and the projection of the covariance matrix on this direction was used as the DFRE to form an envelope for the maximal corrected error.Results show that the DFRE can form an envelope of the maximal corrected error with a set probability,and the integrity performance in the user segment satisfies the Category I precision approach requirement.
