Red mud is a type of highly alkaline waste residue produced in the process of alumina smelting by the Bayer process.Based on the idea of medium calcium content,solid wastes such as red mud and fly ash were used to pre...Red mud is a type of highly alkaline waste residue produced in the process of alumina smelting by the Bayer process.Based on the idea of medium calcium content,solid wastes such as red mud and fly ash were used to prepare non-burnt bricks;and the mass ratio of CaO/SiO2 was selected in the range of 0.88–1.42.Mechanical properties and durability were investigated with a compressive strength test.X-ray diffractometry(XRD),scanning electron microscope(SEM),and Fourier transform infrared spectroscopy(FTIR)techniques were used to characterize the hydration characteristic.The environmental performance was analyzed by Inductively Coupled Plasma Mass Spectrometry(ICP).The results indicated that the mechanical properties and the durability were optimal when the mass ratio of CaO/SiO2 was 1.23.The hydration products were mostly C–S–H gel,ettringite,Na4Ca(Si10All6)O32·12H2O and Ca3Al2(SiO4)(OH)8.They were responsible for the strength development,and the CaO/SiO2 mass ratio of 1.23 had the best polymerized structure.The results of an environmental performance test showed that the heavy metals in the raw materials were well-solidified in the brick.Therefore,this paper provides an effective solution for use of solid wastes in building material.展开更多
The advanced temperature and stress test machine was introduced to determine the early cracking tendency of concrete with inclusion of light-burnt MgO under full restraint by tracking the development of thermal,physic...The advanced temperature and stress test machine was introduced to determine the early cracking tendency of concrete with inclusion of light-burnt MgO under full restraint by tracking the development of thermal,physical and deformation properties.Results showed that light-burnt MgO being incorporated ranging between 4 wt% and 6 wt% of cementitious materials was beneficial to increase the maximum compressive stress and cracking stress of concrete by 0.37 MPa and 0.2 MPa on average respectively.The second zero stress temperature was reduced by 11.4 ℃ and the maximum temperature was slightly reduced while cracking thermal impact was significantly enhanced from 59.8 ℃ to 66.2 ℃.Sensitive anti-cracking coefficient F was forwarded to assess the early cracking tendency of concrete and the inclusion of 4 wt% light-burnt MgO with activity of 109 s ranked the best in crack resistance.展开更多
The identification of burnt forests and their monitoring provide essential information for the suitable management and conservation of these ecosystems. This research focuses on the use of remote sensing with MODIS se...The identification of burnt forests and their monitoring provide essential information for the suitable management and conservation of these ecosystems. This research focuses on the use of remote sensing with MODIS sensor data in a Mediterranean environment, precisely in the Rif region known for its high occurrence of forest fires and the largest burnt areas in Morocco. It mapped the burnt areas during the summer of 2016 using spectral indices from MODIS images, namely the Normalized Burn Ratio (NBR) and the Burnt Area Index for MODIS (BAIM). Two field surveys were used to calibrate spectral indices and validate the maps. First, a monotemporal analysis using a single pre-fire image determined the appropriate threshold of the spectral indices (BAIM and NBR) for burn detecting. Secondly, a multitemporal method was applied based on dBAIM and dNBR images which represented pre-fire and postfire differences of the BAIM and NBR images, respectively. The results show that separate use of monotemporal postfire and multitemporal methods produced an overestimation of the burnt areas. Finally, we propose a new algorithm combining both methods for burnt area mapping that we name Burnt Area Algorithm. MCD45A1 and MCD64A1 MODIS burnt area products were compared to the proposed algorithm. Validation of the estimated burnt areas using reference data of the Moroccan High Commission for Water, Forests and Fight against Desertification showed satisfactory results using the proposed algorithm, with a determination coefficient of 0.68 and a root mean square error of 44.0 ha.展开更多
The study of burnt rocks is beneficial to the discussion on the tectonic movement, paleoclimate and paleogeography that coal seams are subjected to after they were formed. In order to obtain the basic data on the feat...The study of burnt rocks is beneficial to the discussion on the tectonic movement, paleoclimate and paleogeography that coal seams are subjected to after they were formed. In order to obtain the basic data on the features of the burnt rocks, a systematic study of petrology and REE geochemistry on burnt rocks in Shenmu, Northern Shaanxi Province has been done, using the methods of SEM, EDS, susceptibility measurements and ICP-MS. The burnt rocks are divided into two series in the section： the melted rocks and the baked rocks. SEM and EDS analyses reveal that all the minerals show burnt and melted traces, and there are no clay minerals except illite found in the burnt rocks. Susceptibility measurements reveal that the burnt rocks have abnormally high susceptibility values, whereas a geochemical analysis shows that the REE distribution pattern of burnt rocks is similar to that of sedimentary rocks （initial rocks）. In the longitudinal section, with increasing degree of burning （from baked rocks to melted rocks）, the ∑REE gradually decreases, and the total REE of melted rocks is obviously lower than that of baked rocks. Besides, the melted rocks show apparent negative Ce anomalies, while the baked rocks show no anomaly of Ce, and sometimes even show positive anomalies.展开更多
Burnt lime is an important material in steelmaking and its activity degree is a key factor for liquid steel quality. The burnt lime was made by the calcination of limestone in a high pressure electric furnace. The bur...Burnt lime is an important material in steelmaking and its activity degree is a key factor for liquid steel quality. The burnt lime was made by the calcination of limestone in a high pressure electric furnace. The burnt lime mineralogical phases and micro-morphologies were characterized by X-ray diffraction （XRD） and field emission scan- ning electron microscopy （FE-SEM）. The burnt lime activity degree was determined by acid-base titration, the burnt lime pore distribution was measured by mercury intrusion porosimetry （MIP）, and the thermal effect of a mixture of burnt lime and slag was measured by differential scanning calorimetry （DSC）. The results showed that the CaO grain size and pore size of burnt lime made under high pressure were larger than those of burnt lime made under atmos- pheric pressure. The CaO grain size and pore size increased and the laminate phenomenon also occurred clearly under high pressure. The activity degree of burnt lime made under high pressure was greater than that made under atmos- pheric pressure. The maximum activity degree was 437 mL for burnt lime made under a pressure of 0.4 MPa. For the same ratio of CaO to SiOz, the melting temperature, hemisphere temperature and fluidity temperature of slag decreased with increasing burnt lime activity degree. The higher the activity degree the burnt lime had, the better the slag forming occurred. It was advantageous for -2CaO · SiO2 and 3CaO · SiO2 forming at lower temperatures if the burnt lime activity degree was increased.展开更多
In order to study temperature field distribution in burnt surrounding rock and to determine ranges of burnt surrounding rock, coal-wall coking cycle and heat influence in the underground coal gasification(UCG) stope, ...In order to study temperature field distribution in burnt surrounding rock and to determine ranges of burnt surrounding rock, coal-wall coking cycle and heat influence in the underground coal gasification(UCG) stope, based on the Laplace transform and inversion formula, we studied the temperature analytical solution of one-dimensional unsteady heat conduction for multi-layer overlying strata under the first and the forth kinds of boundary conditions, and we also carried out a numerical simulation of twodimensional unsteady heat conduction by the COMSOL multiphysics. The results show that when the boundary temperature of surrounding rock has a linear decrease because of a directional movement of heat source in the UCG flame working face, the temperature in surrounding rock increases first and then decreases with time, the peak of temperature curve decreases gradually and its position moves inside surrounding rock from the boundary. In the surrounding rock of UCG stope, there is an envelope curve of temperature curve clusters. We analyzed the influence of thermophysical parameters on envelope curves and put forward to take envelope curve as the calculation basis for ranges of burnt surrounding rock, coal-wall coking cycle and heat influence. Finally, the concrete numerical values are given by determining those judgement standards and temperature thresholds, which basically tally with the field geophysical prospecting results.展开更多
The present study was carried out at two different gradients of unbumt and burnt Anogeissus latifolia forest sites in the Garhwal region, India. At each gradient, the unburnt and burnt forest sites were further catego...The present study was carried out at two different gradients of unbumt and burnt Anogeissus latifolia forest sites in the Garhwal region, India. At each gradient, the unburnt and burnt forest sites were further categorized into three different elevations, i.e., lower （700 m）, middle （850 m） and upper （1000 m）. At each elevation, the density of trees, saplings and seedlings was higher at the unburnt sites except for trees at the upper elevation which was higher at the burnt sites. The total basal area of each layer of for- est was also higher at the unburnt sites. The study revealed that the lower number of saplings and seedlings at the burnt forest sites might be due to the effect of fire. Most trees in the lower dbh classes were affected by forest fire at the burnt sites which reduced the total density and total basal area of the trees compared to the unburnt sites. The diversity of trees increased with increasing elevation. However, the diversity of saplings and seedlings reduced with increasing elevation.展开更多
BACKGROUND Foreign body aspiration mainly occurs in children,which can cause a severe concurrent syndrome and even death without timely treatment.As a rare foreign body,aspiration of lime is seldom reported,and most c...BACKGROUND Foreign body aspiration mainly occurs in children,which can cause a severe concurrent syndrome and even death without timely treatment.As a rare foreign body,aspiration of lime is seldom reported,and most cases involve a small amount of hydrated lime.Although the symptoms are usually severe,the prognosis is good after suitable treatment.Experience of treatment for lime aspiration is lacking,and this report provides novel evidence for treatment of mass burnt lime aspiration using bronchoscopy.CASE SUMMARY We report an adult with a large amount of burnt lime aspiration.Because of delay in clearance of the inhaled lime in the trachea and bronchus at the local hospital,he suffered several severe complications,including complete occlusion of the right primary bronchus,aeropleura,aerodermectasia,pneumomediastinum,secondary infection and hypoxemia at 4 d after injury.After transferring to our department,bronchoscopy was immediately carried out to clear the lime in the major airway,using foreign body forceps,biopsy forceps,puncture needle,and hairbrush.The patient’s condition recovered rapidly and at 3-months’follow-up,he demonstrated good recovery of the bronchus and lung parenchyma.CONCLUSION After mass lime aspiration,flexible fiberoptic bronchoscopy is suggested as early as possible,using clamping,flushing or cryotherapy.展开更多
The concentrations of two fresh Chinese coals (lignitie and fatty coal ) from dif-ferent geological origin and the corresponding fly and bottom ashes were determined us-ing inductively coupled plasma mass spectrometry...The concentrations of two fresh Chinese coals (lignitie and fatty coal ) from dif-ferent geological origin and the corresponding fly and bottom ashes were determined us-ing inductively coupled plasma mass spectrometry(ICP-MS). The ranges and means of concentrations of these elemennts were given. Based on the combustion simulating ex-periment in the one-dismensional boiler, the contents of REE (rare-earth element) of 18 samples in lignite, fatty coal and their fly and bottom ashes in different combustion condi-tion were determined, and geochemical feature of REE were analyzed.展开更多
Tropical endomyocardial fibrosis (EMF) is a public health problem affecting the children, young adults and elderly individuals in an epidemic fashion in the coastal districts of south India. Due to lack of resources f...Tropical endomyocardial fibrosis (EMF) is a public health problem affecting the children, young adults and elderly individuals in an epidemic fashion in the coastal districts of south India. Due to lack of resources for research in these endemic areas, its etiology remains elusive and hypotheses ranging from infections and allergic causes to malnutrition and toxins have not been tested rigorously. The disease is characterized by endocardial fibrosis and the right ventricle is the cardiac chamber most frequently affected. Patients may present clinically with heart failure and an associated AV (atrioventricular) valve regurgitation is common. Several features of the advanced disease called as “burnt-out” stage of endomyocardial fibrosis (EMF) are not fully understood. Background of these case studies described the clinical presentation, echocardiographic features and management of this late stage of the disease.展开更多
煤炭地下气化耦合二氧化碳封存为煤炭行业实现“碳达峰”“碳中和”目标提供了新的途径。然而超临界二氧化碳封存扰动下烧变煤体力学性质损伤可能引起隔离煤柱失稳,易诱发二氧化碳泄露风险甚至造成工程失败。针对目前缺乏超临界二氧化...煤炭地下气化耦合二氧化碳封存为煤炭行业实现“碳达峰”“碳中和”目标提供了新的途径。然而超临界二氧化碳封存扰动下烧变煤体力学性质损伤可能引起隔离煤柱失稳,易诱发二氧化碳泄露风险甚至造成工程失败。针对目前缺乏超临界二氧化碳对烧变煤力学性质影响的研究,以长焰煤为研究对象,利用自制的超临界二氧化碳饱和增压装置,开展了烧变长焰煤的超临界二氧化碳浸泡力学试验。研究结果表明:①随着温度的升高和超临界二氧化碳浸泡时间增加,烧变煤样的单轴抗压强度减小,温度对烧变煤样单轴抗压强度影响更大;②超临界二氧化碳浸泡时间与温度使烧变煤样弹性模量降低,两者与弹性模量总体呈负相关关系,烧变煤样弹性模量对温度影响更为敏感;③烧变煤样抗拉强度随着温度以及超临界CO_(2)浸泡时间的增加而减弱,温度作用下烧变煤样抗拉强度变化更为剧烈。结合力学试验数据,建立了温度、浸泡时间和烧变煤样抗压强度、弹性模量、抗拉强度的关系函数,并利用XRD(X-RayDiffraction)与SEM(Scanning Electron Microscope)揭示了超临界二氧化碳浸泡作用下烧变长焰煤弱化机理。展开更多
Human-made and natural disasters can result in severely fragmented,compromised,and commingled human remains.The related disaster victim identification(DVI)operations are invariably challenging,with the state of the re...Human-made and natural disasters can result in severely fragmented,compromised,and commingled human remains.The related disaster victim identification(DVI)operations are invariably challenging,with the state of the remains potentially precluding some identifications.Practitioners involved in these DVI operations will routinely face logistical,practical,and ethical challenges.This review provides information and guidance derived from firsthand experiences to individuals tasked with managing DVI operations with fragmented human remains.We outline several key issues that should be addressed during disaster preparedness planning and at the outset of an operation,when incident-specific strategies are developed.Specific challenges during recovery and examination of fragmented remains are addressed,highlighting the importance of experienced specialists at the scene and in the mortuary.DNA sample selection and sampling techniques are reviewed,as well as downstream effects of commingling and contamination,which can complicate reconciliation and emphasise the need for rigorous quality control.We also touch on issues that may arise during communication with families.While recommendations are provided,they are not intended as proscriptive policy but rather as an addition to the general recommendations given in the International Criminal Police Organization(INTERPOL)DVI Guide,to inform preparative discussions between government officials,judiciary,police,and forensic specialists.展开更多
基金the financial support from the National Natural Science Foundation of China (No.51574024)Fundamental Research Funds for the Central Universities (FRF-TP-18-005B1)Technological Research and Development Programs of China Railways Corporation (No.2017G006-J)
文摘Red mud is a type of highly alkaline waste residue produced in the process of alumina smelting by the Bayer process.Based on the idea of medium calcium content,solid wastes such as red mud and fly ash were used to prepare non-burnt bricks;and the mass ratio of CaO/SiO2 was selected in the range of 0.88–1.42.Mechanical properties and durability were investigated with a compressive strength test.X-ray diffractometry(XRD),scanning electron microscope(SEM),and Fourier transform infrared spectroscopy(FTIR)techniques were used to characterize the hydration characteristic.The environmental performance was analyzed by Inductively Coupled Plasma Mass Spectrometry(ICP).The results indicated that the mechanical properties and the durability were optimal when the mass ratio of CaO/SiO2 was 1.23.The hydration products were mostly C–S–H gel,ettringite,Na4Ca(Si10All6)O32·12H2O and Ca3Al2(SiO4)(OH)8.They were responsible for the strength development,and the CaO/SiO2 mass ratio of 1.23 had the best polymerized structure.The results of an environmental performance test showed that the heavy metals in the raw materials were well-solidified in the brick.Therefore,this paper provides an effective solution for use of solid wastes in building material.
基金Funded by National Natural Science Foundation of China(No.50539010)China Central Non-profit Research Funds of MWR(Nos.200901066,YWF0907)
文摘The advanced temperature and stress test machine was introduced to determine the early cracking tendency of concrete with inclusion of light-burnt MgO under full restraint by tracking the development of thermal,physical and deformation properties.Results showed that light-burnt MgO being incorporated ranging between 4 wt% and 6 wt% of cementitious materials was beneficial to increase the maximum compressive stress and cracking stress of concrete by 0.37 MPa and 0.2 MPa on average respectively.The second zero stress temperature was reduced by 11.4 ℃ and the maximum temperature was slightly reduced while cracking thermal impact was significantly enhanced from 59.8 ℃ to 66.2 ℃.Sensitive anti-cracking coefficient F was forwarded to assess the early cracking tendency of concrete and the inclusion of 4 wt% light-burnt MgO with activity of 109 s ranked the best in crack resistance.
基金the Faculty of Science and Technology of Beni Mellal for their logistical and financial support for the PhD project No. RNES44/13
文摘The identification of burnt forests and their monitoring provide essential information for the suitable management and conservation of these ecosystems. This research focuses on the use of remote sensing with MODIS sensor data in a Mediterranean environment, precisely in the Rif region known for its high occurrence of forest fires and the largest burnt areas in Morocco. It mapped the burnt areas during the summer of 2016 using spectral indices from MODIS images, namely the Normalized Burn Ratio (NBR) and the Burnt Area Index for MODIS (BAIM). Two field surveys were used to calibrate spectral indices and validate the maps. First, a monotemporal analysis using a single pre-fire image determined the appropriate threshold of the spectral indices (BAIM and NBR) for burn detecting. Secondly, a multitemporal method was applied based on dBAIM and dNBR images which represented pre-fire and postfire differences of the BAIM and NBR images, respectively. The results show that separate use of monotemporal postfire and multitemporal methods produced an overestimation of the burnt areas. Finally, we propose a new algorithm combining both methods for burnt area mapping that we name Burnt Area Algorithm. MCD45A1 and MCD64A1 MODIS burnt area products were compared to the proposed algorithm. Validation of the estimated burnt areas using reference data of the Moroccan High Commission for Water, Forests and Fight against Desertification showed satisfactory results using the proposed algorithm, with a determination coefficient of 0.68 and a root mean square error of 44.0 ha.
文摘The study of burnt rocks is beneficial to the discussion on the tectonic movement, paleoclimate and paleogeography that coal seams are subjected to after they were formed. In order to obtain the basic data on the features of the burnt rocks, a systematic study of petrology and REE geochemistry on burnt rocks in Shenmu, Northern Shaanxi Province has been done, using the methods of SEM, EDS, susceptibility measurements and ICP-MS. The burnt rocks are divided into two series in the section： the melted rocks and the baked rocks. SEM and EDS analyses reveal that all the minerals show burnt and melted traces, and there are no clay minerals except illite found in the burnt rocks. Susceptibility measurements reveal that the burnt rocks have abnormally high susceptibility values, whereas a geochemical analysis shows that the REE distribution pattern of burnt rocks is similar to that of sedimentary rocks （initial rocks）. In the longitudinal section, with increasing degree of burning （from baked rocks to melted rocks）, the ∑REE gradually decreases, and the total REE of melted rocks is obviously lower than that of baked rocks. Besides, the melted rocks show apparent negative Ce anomalies, while the baked rocks show no anomaly of Ce, and sometimes even show positive anomalies.
基金Sponsored by National Natural Science Foundation of China(51174075,51274084)Natural Science Foundation of Hebei Province of China(E2012209024,E2014209157)
文摘Burnt lime is an important material in steelmaking and its activity degree is a key factor for liquid steel quality. The burnt lime was made by the calcination of limestone in a high pressure electric furnace. The burnt lime mineralogical phases and micro-morphologies were characterized by X-ray diffraction （XRD） and field emission scan- ning electron microscopy （FE-SEM）. The burnt lime activity degree was determined by acid-base titration, the burnt lime pore distribution was measured by mercury intrusion porosimetry （MIP）, and the thermal effect of a mixture of burnt lime and slag was measured by differential scanning calorimetry （DSC）. The results showed that the CaO grain size and pore size of burnt lime made under high pressure were larger than those of burnt lime made under atmos- pheric pressure. The CaO grain size and pore size increased and the laminate phenomenon also occurred clearly under high pressure. The activity degree of burnt lime made under high pressure was greater than that made under atmos- pheric pressure. The maximum activity degree was 437 mL for burnt lime made under a pressure of 0.4 MPa. For the same ratio of CaO to SiOz, the melting temperature, hemisphere temperature and fluidity temperature of slag decreased with increasing burnt lime activity degree. The higher the activity degree the burnt lime had, the better the slag forming occurred. It was advantageous for -2CaO · SiO2 and 3CaO · SiO2 forming at lower temperatures if the burnt lime activity degree was increased.
基金supported by the State Key Laboratory of Coal Resources and Safe Mining (No. SKLCRSM10X04)the National Natural Science Foundation of China ((No. 21243006)+1 种基金the Foundation of Ministry of Education of China ((No. 02019)the Priority Academic Program Development of Jiangsu Higher Education Institutions (No.SZBF2011-6-B35)
文摘In order to study temperature field distribution in burnt surrounding rock and to determine ranges of burnt surrounding rock, coal-wall coking cycle and heat influence in the underground coal gasification(UCG) stope, based on the Laplace transform and inversion formula, we studied the temperature analytical solution of one-dimensional unsteady heat conduction for multi-layer overlying strata under the first and the forth kinds of boundary conditions, and we also carried out a numerical simulation of twodimensional unsteady heat conduction by the COMSOL multiphysics. The results show that when the boundary temperature of surrounding rock has a linear decrease because of a directional movement of heat source in the UCG flame working face, the temperature in surrounding rock increases first and then decreases with time, the peak of temperature curve decreases gradually and its position moves inside surrounding rock from the boundary. In the surrounding rock of UCG stope, there is an envelope curve of temperature curve clusters. We analyzed the influence of thermophysical parameters on envelope curves and put forward to take envelope curve as the calculation basis for ranges of burnt surrounding rock, coal-wall coking cycle and heat influence. Finally, the concrete numerical values are given by determining those judgement standards and temperature thresholds, which basically tally with the field geophysical prospecting results.
文摘The present study was carried out at two different gradients of unbumt and burnt Anogeissus latifolia forest sites in the Garhwal region, India. At each gradient, the unburnt and burnt forest sites were further categorized into three different elevations, i.e., lower （700 m）, middle （850 m） and upper （1000 m）. At each elevation, the density of trees, saplings and seedlings was higher at the unburnt sites except for trees at the upper elevation which was higher at the burnt sites. The total basal area of each layer of for- est was also higher at the unburnt sites. The study revealed that the lower number of saplings and seedlings at the burnt forest sites might be due to the effect of fire. Most trees in the lower dbh classes were affected by forest fire at the burnt sites which reduced the total density and total basal area of the trees compared to the unburnt sites. The diversity of trees increased with increasing elevation. However, the diversity of saplings and seedlings reduced with increasing elevation.
文摘BACKGROUND Foreign body aspiration mainly occurs in children,which can cause a severe concurrent syndrome and even death without timely treatment.As a rare foreign body,aspiration of lime is seldom reported,and most cases involve a small amount of hydrated lime.Although the symptoms are usually severe,the prognosis is good after suitable treatment.Experience of treatment for lime aspiration is lacking,and this report provides novel evidence for treatment of mass burnt lime aspiration using bronchoscopy.CASE SUMMARY We report an adult with a large amount of burnt lime aspiration.Because of delay in clearance of the inhaled lime in the trachea and bronchus at the local hospital,he suffered several severe complications,including complete occlusion of the right primary bronchus,aeropleura,aerodermectasia,pneumomediastinum,secondary infection and hypoxemia at 4 d after injury.After transferring to our department,bronchoscopy was immediately carried out to clear the lime in the major airway,using foreign body forceps,biopsy forceps,puncture needle,and hairbrush.The patient’s condition recovered rapidly and at 3-months’follow-up,he demonstrated good recovery of the bronchus and lung parenchyma.CONCLUSION After mass lime aspiration,flexible fiberoptic bronchoscopy is suggested as early as possible,using clamping,flushing or cryotherapy.
基金Supported by the National Natural Science Key Foundation of China (40133010) Educational Natural Science Foundation of Anhui (2004kj114) Natural Science Foundation of Anhui University of Science and Technology for Ph.D to Research(DG414)
文摘The concentrations of two fresh Chinese coals (lignitie and fatty coal ) from dif-ferent geological origin and the corresponding fly and bottom ashes were determined us-ing inductively coupled plasma mass spectrometry(ICP-MS). The ranges and means of concentrations of these elemennts were given. Based on the combustion simulating ex-periment in the one-dismensional boiler, the contents of REE (rare-earth element) of 18 samples in lignite, fatty coal and their fly and bottom ashes in different combustion condi-tion were determined, and geochemical feature of REE were analyzed.
文摘Tropical endomyocardial fibrosis (EMF) is a public health problem affecting the children, young adults and elderly individuals in an epidemic fashion in the coastal districts of south India. Due to lack of resources for research in these endemic areas, its etiology remains elusive and hypotheses ranging from infections and allergic causes to malnutrition and toxins have not been tested rigorously. The disease is characterized by endocardial fibrosis and the right ventricle is the cardiac chamber most frequently affected. Patients may present clinically with heart failure and an associated AV (atrioventricular) valve regurgitation is common. Several features of the advanced disease called as “burnt-out” stage of endomyocardial fibrosis (EMF) are not fully understood. Background of these case studies described the clinical presentation, echocardiographic features and management of this late stage of the disease.
文摘煤炭地下气化耦合二氧化碳封存为煤炭行业实现“碳达峰”“碳中和”目标提供了新的途径。然而超临界二氧化碳封存扰动下烧变煤体力学性质损伤可能引起隔离煤柱失稳,易诱发二氧化碳泄露风险甚至造成工程失败。针对目前缺乏超临界二氧化碳对烧变煤力学性质影响的研究,以长焰煤为研究对象,利用自制的超临界二氧化碳饱和增压装置,开展了烧变长焰煤的超临界二氧化碳浸泡力学试验。研究结果表明:①随着温度的升高和超临界二氧化碳浸泡时间增加,烧变煤样的单轴抗压强度减小,温度对烧变煤样单轴抗压强度影响更大;②超临界二氧化碳浸泡时间与温度使烧变煤样弹性模量降低,两者与弹性模量总体呈负相关关系,烧变煤样弹性模量对温度影响更为敏感;③烧变煤样抗拉强度随着温度以及超临界CO_(2)浸泡时间的增加而减弱,温度作用下烧变煤样抗拉强度变化更为剧烈。结合力学试验数据,建立了温度、浸泡时间和烧变煤样抗压强度、弹性模量、抗拉强度的关系函数,并利用XRD(X-RayDiffraction)与SEM(Scanning Electron Microscope)揭示了超临界二氧化碳浸泡作用下烧变长焰煤弱化机理。
文摘Human-made and natural disasters can result in severely fragmented,compromised,and commingled human remains.The related disaster victim identification(DVI)operations are invariably challenging,with the state of the remains potentially precluding some identifications.Practitioners involved in these DVI operations will routinely face logistical,practical,and ethical challenges.This review provides information and guidance derived from firsthand experiences to individuals tasked with managing DVI operations with fragmented human remains.We outline several key issues that should be addressed during disaster preparedness planning and at the outset of an operation,when incident-specific strategies are developed.Specific challenges during recovery and examination of fragmented remains are addressed,highlighting the importance of experienced specialists at the scene and in the mortuary.DNA sample selection and sampling techniques are reviewed,as well as downstream effects of commingling and contamination,which can complicate reconciliation and emphasise the need for rigorous quality control.We also touch on issues that may arise during communication with families.While recommendations are provided,they are not intended as proscriptive policy but rather as an addition to the general recommendations given in the International Criminal Police Organization(INTERPOL)DVI Guide,to inform preparative discussions between government officials,judiciary,police,and forensic specialists.
