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Geological characteristics and models of fault-foldfracture body in deep tight sandstone of the second member of Upper Triassic Xujiahe Formation in Xinchang structural belt of Sichuan Basin,SW China 被引量:1
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作者 LIU Junlong LIU Zhongqun +8 位作者 LIU Zhenfeng LIU Yali SHEN Baojian XIAO Kaihua BI Youyi WANG Xiaowen WANG Ail FAN Lingxiao LI Jitongl 《Petroleum Exploration and Development》 SCIE 2023年第3期603-614,共12页
In the second member of the Upper Triassic Xujiahe Formation(T_(3)x_(2))in the Xinchang area,western Sichuan Basin,only a low percent of reserves has been recovered,and the geological model of gas reservoir sweet spot... In the second member of the Upper Triassic Xujiahe Formation(T_(3)x_(2))in the Xinchang area,western Sichuan Basin,only a low percent of reserves has been recovered,and the geological model of gas reservoir sweet spot remains unclear.Based on a large number of core,field outcrop,test and logging-seismic data,the T_(3)x_(2) gas reservoir in the Xinchang area is examined.The concept of fault-fold-fracture body(FFFB)is proposed,and its types are recognized.The main factors controlling fracture development are identified,and the geological models of FFFB are established.FFFB refers to faults,folds and associated fractures reservoirs.According to the characteristics and genesis,FFFBs can be divided into three types:fault-fracture body,fold-fracture body,and fault-fold body.In the hanging wall of the fault,the closer to the fault,the more developed the effective fractures;the greater the fold amplitude and the closer to the fold hinge plane,the more developed the effective fractures.Two types of geological models of FFFB are established:fault-fold fracture,and matrix storage and permeability.The former can be divided into two subtypes:network fracture,and single structural fracture,and the later can be divided into three subtypes:bedding fracture,low permeability pore,and extremely low permeability pore.The process for evaluating favorable FFFB zones was formed to define favorable development targets and support the well deployment for purpose of high production.The study results provide a reference for the exploration and development of deep tight sandstone oil and gas reservoirs in China. 展开更多
关键词 fault-fold-fracture body fracture control factor genetic characteristics geological model deep layer tight sandstone Xinchang structural belt Upper Triassic Xujiahe Formation Sichuan Basin
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Fracture evolution around pre-existing cylindrical cavities in brittle rocks under uniaxial compression 被引量:25
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作者 赵兴东 张洪训 朱万成 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期806-815,共10页
The development of fracture around pre-existing cylindrical cavities in brittle rocks was examined using physical models and acoustic emission technique. The experimental results indicate that when granite blocks cont... The development of fracture around pre-existing cylindrical cavities in brittle rocks was examined using physical models and acoustic emission technique. The experimental results indicate that when granite blocks containing one pre-existing cylindrical cavity are loaded in uniaxial compression condition, the profiles of cracks around the cavity can be characterized by tensile cracking (splitting parallel to the axial compression direction) at the roof-floor, compressive crack at two side walls, and remote or secondary cracks at the perimeter of the cavity. Moreover, fracture around cavity is size-dependent. In granite blocks containing pre-existing half-length cylindrical cavities, compressive stress concentration is found to initiate at the two sidewalls and induce shear crack propagation and coalescence. In granite blocks containing multiple parallel cylindrical cavities, the adjacent cylindrical cavities can influence each other and the eventual failure mode is determined by the interaction of tensile, compressive and shear stresses. Experimental results show that both tensile and compressive stresses play an important role in fracture evolution process around cavities in brittle rocks. 展开更多
关键词 cylindrical cavity fracture evolution uniaxial compression acoustic emission event location slabbing
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Methods of predicting vertebral body fractures of the lumbar spine 被引量:6
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作者 Gurudattsingh B Sisodia 《World Journal of Orthopedics》 2013年第4期241-247,共7页
Lumbar vertebral body(VB) fractures are increasingly common in an ageing population that is at greater risk of osteoporosis and metastasis. This review aims to identify different models, as alternatives to bone minera... Lumbar vertebral body(VB) fractures are increasingly common in an ageing population that is at greater risk of osteoporosis and metastasis. This review aims to identify different models, as alternatives to bone mineral density(BMD), which may be applied in order to predict VB failure load and fracture risk. The most representative models are those that take account of normal spinal kinetics and assess the contribution of the cortical shell to vertebral strength. Overall, predictive models for VB fracture risk should encompass a range of important parameters including BMD, geometric measures and patient-specific factors. As interventions like vertebroplasty increase in popularity for VB fracture treatment and prevention, such models are likely to play a significant role in the clinical decision-making process. More biomechanical research is required, however, to reduce the risks of post-operative adjacent VB fractures. 展开更多
关键词 LUMBAR SPINE VERTEBRAL body fracture Prediction Model Bone MINERAL density OSTEOPOROSIS
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Delayed presentation of a loose body in undisplaced paediatric talar neck fracture 被引量:2
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作者 Vishal Patel Benjamin Bloch +1 位作者 Nicholas Johnson Jitendra Mangwani 《World Journal of Orthopedics》 2014年第3期398-401,共4页
Fractures of the talus are rare in children.A high index of suspicion is needed to avoid missing such an injury,which is not an uncommon occurrence especially with undisplaced fractures.We present an unusual case of a... Fractures of the talus are rare in children.A high index of suspicion is needed to avoid missing such an injury,which is not an uncommon occurrence especially with undisplaced fractures.We present an unusual case of an undisplaced talar neck fracture in a five-year-old child leading to a delayed presentation of a symptomatic osteochondral loose body in the ankle joint.To our knowledge there are no reports in the literature of osteochondral loose bodies occurring in conjunction with an associated undisplaced talar neck fracture in either children or adults.The loose body was removed using anterior ankle arthroscopy.The child had an uneventful post operative recovery and regained full range of movement and function of his ankle joint and was discharged at one year follow-up.We aim to highlight the need to have a low threshold to further evaluate symptomatic children after fracture healing of an undisplaced talar neck fracture for a possible associated loose bodyin the ankle joint. 展开更多
关键词 TALUS fracture LOOSE body ANKLE ARTHROSCOPY Children
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Pancreatic Body Fracture does not Necessarily Imply Loss of Ductal Integrity Following Blunt Trauma Abdomen—A Rare Image 被引量:1
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作者 Disha Syal Arindam Ghosh 《Surgical Science》 2011年第5期246-247,共2页
Pancreatic injuries can result in significant morbidity and mortality if missed or unnoticed and also pose a great challenge in terms of diagnosis and treatment. We present a case of an 11 year old boy presenting with... Pancreatic injuries can result in significant morbidity and mortality if missed or unnoticed and also pose a great challenge in terms of diagnosis and treatment. We present a case of an 11 year old boy presenting with history of blunt trauma abdomen following handle bar injury. He had signs of abdominal distension and CECT of the abdomen showed transection of the pancreas in the region of junction between the body and tail. On exploratory laparotomy there was rupture at junction of body and tail of pancreas with intact pancreatic duct and a spleen preserving distal pancreatectomy was performed. In the presence of an intact pancreatic duct conservative management should be offered however this patient underwent spleen preserving distal pancreatectomy because of pancreatitis and necrosis ensuing in the pancreatic remnant margin. Hence, complete transection does not necessarily mean loss of ductal integrity and decision to preserve or remove the distal pancreas should not be based merely on ductal integrity but probably other factors also i.e. pancreatitis and necrosis. 展开更多
关键词 BLUNT Trauma ABDOMEN PANCREATIC body fracture Management Intact PANCREATIC Duct
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Controlling factors of remaining oil distribution after water flooding and enhanced oil recovery methods for fracturecavity carbonate reservoirs in Tahe Oilfield 被引量:4
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作者 ZHENG Songqing YANG Min +5 位作者 KANG Zhijiang LIU Zhongchun LONG Xibin LIU Kunyan LI Xiaobo ZHANG Shiliang 《Petroleum Exploration and Development》 2019年第4期786-795,共10页
Based on comprehensive analysis of core, well logging, seismic and production data, the multi-scale reservoir space, reservoir types, spatial shape and distribution of fractures and caves, and the configuration relati... Based on comprehensive analysis of core, well logging, seismic and production data, the multi-scale reservoir space, reservoir types, spatial shape and distribution of fractures and caves, and the configuration relationship with production wells in fracture-cavity carbonate reservoirs were studied systematically, the influence of them on the distribution of residual oil was analyzed, and the main controlling factors mode of residual oil distribution after water flooding was established. Enhanced oil recovery methods were studied considering the development practice of Tahe oilfield. Research shows that the main controlling factors of residual oil distribution after water flooding in fracture-cavity carbonate reservoirs can be classified into four categories: local high point, insufficient well control, flow channel shielding and weak hydrodynamic. It is a systematic project to improve oil recovery in fracture-cavity carbonate reservoirs. In the stage of natural depletion, production should be well regulated to prevent bottom water channeling. In the early stage of waterflooding, injection-production relationship should be constructed according to reservoir type, connectivity and spatial location to enhance control and producing degree of waterflooding and minimize remaining oil. In the middle and late stage, according to the main controlling factors and distribution characteristics of remaining oil after water flooding, remaining oil should be tapped precisely by making use of gravity differentiation and capillary force imbibition, enhancing well control, disturbing the flow field and so on. Meanwhile, backup technologies of reservoir stimulation, new injection media, intelligent optimization etc. should be developed, smooth shift from water injection to gas injection should be ensured to maximize oil recovery. 展开更多
关键词 CARBONATE rock fracture-cavity RESERVOIR multiple scale REMAINING OIL distribution main controlling factor enhanced OIL recovery
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Application of Spectral Decomposition to Detection of Fracture-Cavity Carbonate Reservoir Beds in the Tahe OUfield,Tarim Basin,NW China 被引量:1
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作者 LIU Xiaoping YANG Xiaolan +1 位作者 ZHANG Yazhong HAN Long 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第3期530-536,共7页
Ordovician fracture-cavity carbonate reservoir beds are the major type of producing formations in the Tahe oilfield, Tarim Basin. The seismic responses of these beds clearly changes depending on the different distance... Ordovician fracture-cavity carbonate reservoir beds are the major type of producing formations in the Tahe oilfield, Tarim Basin. The seismic responses of these beds clearly changes depending on the different distance of the fracture-cavity reservoir bed from the top of the section. The seismic reflection becomes weak or is absent when the fracture-cavity reservoir beds are less than 20 ms below the top Ordovician. The effect on top Ordovician reflection became weaker with deeper burial of fracture-cavity reservoir beds but the developed deep fracture-cavity reservoir beds caused stronger reflection in the interior of the Ordovician. This interior reflection can be divided into strong long-axis, irregular and bead string reflections, and was present 80 ms below the top Ordovician. Aimed at understanding reflection characteristics, the spectral decomposition technique, which uses frequency to "tune-in" bed thickness, was used to predict Ordovician fracture-cavity carbonate formations in the Tahe oilfield. Through finely adjusting the processing parameters of spectral decomposition, it was found that the slice at 30 Hz of the tuned data cube can best represent reservoir bed development. Two large N-S-trending strong reflection belts in the mid-western part of the study area along wells TK440- TK427-TK417B and in the eastern part along wells TK404-TK409 were observed distinctly on the 30 Hz slice and 4-D time-frequency data cube carving. A small N-S trending reflection belt in the southern part along wells T403-TK446B was also clearly identified. The predicted reservoir bed development area coincides with the fracture-cavities connection area confirmed by drilling pressure testing results. Deep karst cavities occur basically in three reservoir bed-development belts identified by the Ordovician interior strong reflection. Spectral decomposition proved to be a useful technique in identifying fracture-cavity reservoir beds. 展开更多
关键词 Seismic response tuning cube 4-D time-frequency data cube fracture-cavity reservoir bed Ordovician carbonate Tahe oilfield Xinjiang
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Influence of different operation methods on vertebral body parameters and GH-IGF axis of patients with thoracolumbar bursts fractures
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作者 Qing-Bo Zhu 《Journal of Hainan Medical University》 2017年第1期120-122,共3页
Objective:To observe the influence situation of different operation methods on the vertebral body parameters and GH-IGF axis of patients with thoracolumbar bursts fractures.Methods:A total of 50 surgical patients with... Objective:To observe the influence situation of different operation methods on the vertebral body parameters and GH-IGF axis of patients with thoracolumbar bursts fractures.Methods:A total of 50 surgical patients with thoracolumbar bursts fractures from February 2014 to January 2016 were selected as the research object, and 50 patients with fractures were divided into two groups by the principle of random allocation, then the group A were treated with surgical treatment by anterior approach, the group B were treated with surgical treatment by posterior approach, then the vertebral body parameters and the serum expression levels of GH-IGF axis indexes of two groups before the surgery and at different time after the surgery were compared.Results: The vertebral body parameters and the serum expression levels of GH-IGF axis indexes of two groups before the surgery were compared (allP>0.05), while the vertebral body parameters and the serum expression levels of GH-IGF axis indexes of two groups at different time after the surgery were all significantly better than those before the surgery, and the results of group B were all better than those of group A (allP<0.05).Conclusions:The influence of surgical treatment by posterior approach for the vertebral body parameters and GH-IGF axis of patients with thoracolumbar bursts fractures are obviously better than those of surgical treatment by anterior approach, so the application value of surgical treatment by posterior approach in the patients with fractures is higher. 展开更多
关键词 SURGERY by anterior approach SURGERY by posterior approach THORACOLUMBAR BURSTS fractureS Vertebral body PARAMETERS GH-IGF AXIS
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Grading evaluation and prediction of fracture-cavity reservoirs in Cambrian Longwangmiao Formation of Moxi area,Sichuan Basin,SW China
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作者 WANG Bei LIU Xiangjun SIMA Liqiang 《Petroleum Exploration and Development》 2019年第2期301-313,共13页
By using core, thin section, well logging, seismic, well testing and other data, the reservoir grading evaluation parameters were selected, the classification criterion considering multiple factors for carbonate reser... By using core, thin section, well logging, seismic, well testing and other data, the reservoir grading evaluation parameters were selected, the classification criterion considering multiple factors for carbonate reservoirs in this area were established, and the main factors affecting the development of high quality reservoir were determined. By employing Formation MicroScanner Image(FMI) logging fracture-cavity recognition technology and reservoir seismic waveform classification technology, the spatial distribution of reservoirs of all grades were predicted. On the basis of identifying four types of reservoir space developed in the study area by mercury injection experiment, a classification criterion was established using four reservoir grading evaluation parameters, median throat radius, effective porosity and effective permeability of fracture-cavity development zone, relationship between fracture and dissolution pore development and assemblage, and the reservoirs in the study area were classified into grade I high quality reservoir of fracture and cavity type, grade II average reservoir of fracture and porosity type, grade Ⅲ poor reservoir of intergranular pore type. Based on the three main factors controlling the development of high quality reservoir, structural location, sedimentary facies and epigenesis, the distribution of the 3 grades reservoirs in each well area and formation were predicted using geophysical response and percolation characteristics. Follow-up drilling has confirmed that the classification evaluation standard and prediction methods established are effective. 展开更多
关键词 Sichuan Basin Moxi area CAMBRIAN Longwangmiao Formation carbonate rock fracture-cavity RESERVOIR RESERVOIR GRADING EVALUATION RESERVOIR PREDICTION
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Observation on Activities of Air Sac in Opened Body Cavity of Chicken
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作者 张金龙 李新华 贾胜军 《Agricultural Science & Technology》 CAS 2015年第6期1195-1198,共4页
The body cavity of chicken under anesthesia was opened, and then the state of breathing and activities of air sac wal were observed. The results showed that, although the body cavity was opened, the chicken could stil... The body cavity of chicken under anesthesia was opened, and then the state of breathing and activities of air sac wal were observed. The results showed that, although the body cavity was opened, the chicken could stil breathe. When the chicken breathed in, the chest sidewal , thoracico-abdominal diaphragm and lung diaphragm al initiatively became larger, inflating the prethoracic and metathoracic air sacs; the cervical, clavicular and abdominal air sac wal s al contracted, shrinking the air sacs. When the chicken breathed out, the chest sidewal , thoracico-ab-dominal diaphragm and lung diaphragm initiatively contracted, shrinking the pretho-racic and metathoracic air sacs; the cervical, clavicular and abdominal air sac wal s al expanded, expanding the air sacs. Therefore, the chicken could stil breathe after the body cavity was opened. When the chicken breathed in, the prethoracic and metathoracic air sacs were al expanded, and the air flowed from the cervical, clav-icular and abdominal air sacs and respiratory tract to the prethoracic and metatho-racic air sacs through the lung, shrinking the cervical, clavicular and abdominal air sacs; when the chicken breathed out, the prethoracic and metathoracic air sacs wal s al contracted, and the air was extruded from the prethoracic and metathoracic air sacs into the cervical, clavicular and abdominal air sacs and respiratory tract trough the lung, expanding the cervical, clavicular and abdominal air sacs. During the entire breathing process, the prethoracic and metathoracic air sacs al can ex-pand and shrink initiatively, making the air flow though the lung. 展开更多
关键词 CHICKEN body cavity BREATH Air sac
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Experimental Investigation of the Characteristics of an Artificial Cavity During the Water-Exit of a Slender Body 被引量:4
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作者 Guoqiang Fu Jiaolong Zhao +1 位作者 Liping Sun Yang Lu 《Journal of Marine Science and Application》 CSCD 2018年第4期578-584,共7页
Experimental studies are carried out with slender bodies vertically exiting out of the water using a high-speed camera. The mechanisms for the formation, development, and collapse of the cavity around the slender body... Experimental studies are carried out with slender bodies vertically exiting out of the water using a high-speed camera. The mechanisms for the formation, development, and collapse of the cavity around the slender body are explored. The dynamic characteristics of the shoulder cavity and the trail cavity during the water-exit of low-speed bodies are analyzed for various water depths and initial velocities. The results show that the initial velocity has a great influence on the formation, development, and collapse of the cavity. The length and the thickness of the shoulder cavity vary non-linearly with the depth. 展开更多
关键词 Water-exit Slender body cavity development cavity COLLAPSE EXPERIMENTAL investigation
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Managements of osteoporotic vertebral compression fractures:A narrative review 被引量:7
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作者 Devon Patel Jiayong Liu Nabil A Ebraheim 《World Journal of Orthopedics》 2022年第6期564-573,共10页
Osteoporotic vertebral compression fractures(OVCFs)are the most common fragility fracture and significantly influence the quality of life in the elderly.Currently,the literature lacks a comprehensive narrative review ... Osteoporotic vertebral compression fractures(OVCFs)are the most common fragility fracture and significantly influence the quality of life in the elderly.Currently,the literature lacks a comprehensive narrative review of the management of OVCFs.The purpose of this study is to review background information,diagnosis,and surgical and non-surgical management of the OVCFs.A comprehensive search of PubMed and Google Scholar for articles in the English language between 1980 and 2021 was performed.Combinations of the following terms were used:compression fractures,vertebral compression fractures,osteoporosis,osteoporotic compression fractures,vertebroplasty,kyphoplasty,bisphosphonates,calcitonin,and osteoporosis treatments.Additional articles were also included by examining the reference list of articles found in the search.OVCFs,especially those that occur over long periods,can be asymptomatic.Symptoms of acute OVCFs include pain localized to the mid-line spine,a loss in height,and decreased mobility.The primary treatment regimens are pain control,medication management,vertebral augmentation,and anterior or posterior decompression and reconstructions.Pain control can be achieved with acetaminophen or nonsteroidal anti-inflammatory drugs for mild pain or opioids and/or calcitonin for moderate to severe pain.Bisphosphonates and denosumab are the first-line treatments for osteoporosis.Vertebroplasty and kyphoplasty are reserved for patients who have not found symptomatic relief through conservative methods and are effective in achieving pain relief.Vertebroplasty is less technical and cheaper than kyphoplasty but could have more complications.Calcium and vitamin D supplementation can have a protective and therapeutic effect.Management of OVCFs must be combined with multiple approaches.Appropriate exercises and activity modification are important in fracture prevention.Medication with different mechanisms of action is a critical long-term causal treatment strategy.The minimally invasive surgical interventions such as vertebroplasty and kyphoplasty are reserved for patients not responsive to conservative therapy and are recognized as efficient stopgap treatment methods.Posterior decompression and fixation or Anterior decompression and reconstruction may be required if neurological deficits are present.The detailed pathogenesis and related targeted treatment options still need to be developed for better clinical outcomes. 展开更多
关键词 Vertebral body OSTEOPOROSIS Fragility fractures Osteoporotic vertebral compression fractures KYPHOPLASTY VERTEBROPLASTY
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Fracture resistance of posterior teeth restored with modern restorative materials 被引量:1
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作者 Ibrahim M. Hamouda Salah H. Shehata 《The Journal of Biomedical Research》 CAS 2011年第6期418-424,共7页
We studied the fracture resistance of maxillary premolars restored with recent restorative materials. Fifty maxillary premolars were divided into five groups: Group 1 were unprepared teeth; Group 2 were teeth prepare... We studied the fracture resistance of maxillary premolars restored with recent restorative materials. Fifty maxillary premolars were divided into five groups: Group 1 were unprepared teeth; Group 2 were teeth prepared without restoration; Group 3 were teeth restored with tetric ceram HB; Group 4 were teeth restored with InTen S; and Group 5 were teeth restored with Admira. The samples were tested using a universal testing machine. Peak loads at fracture were recorded. The teeth restored with Admira had the highest fracture resistance followed by those restored with InTen-S and tetric ceram HB. Prepared, unrestored teeth were the weakest group. There was a significant difference between the fracture resistance of intact teeth and the prepared, unrestored teeth. There was also a significant difference among the tested restorative materials. Teeth restored with Admira showed no significant difference when compared with the unprepared teeth. It was concluded that the teeth restored with Admira exhibited the highest fracture resistance. 展开更多
关键词 fracture resistance composite resin adhesives mesio-occlusal-distal (MOD) cavities
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Fractured zone height of longwall mining and its effects on the overburden aquifers 被引量:12
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作者 Guo Wenbing Zou Youfeng Hou Quanlin 《International Journal of Mining Science and Technology》 SCIE EI 2012年第5期603-606,共4页
As mining depth becomes deeper and deeper,the possibility of undermining overburden aquifers is increasing.It is very important for coal miners to undertake studies on the height of fractured zone during longwall mini... As mining depth becomes deeper and deeper,the possibility of undermining overburden aquifers is increasing.It is very important for coal miners to undertake studies on the height of fractured zone during longwall mining and the effects of longwall mining on the underground water while mining under surface water bodies and underground aquifers.In order to study this problem,piezometers for monitoring underground water levels were installed above the longwall panels in an American coalmine.Large amounts of pre-mining,during mining and post-mining monitoring data were collected.Based on the data,the heights of fractured zones were obtained and the effects of longwall mining on the underground water were studied.The results demonstrate that when the piezometer monitoring wells had an interburden thickness of less than 72.7 m,the groundwater level decreased immediately to immeasurable levels and the wells went dry after undermining the face of longwall.The height of the fractured zone is 72.7-85.3 m in the geological and mining conditions.The results also show that the calculated values of fractured zones by the empirical formulae used in China are smaller than the actual results.Therefore,it is not always safe to use them for analyses while mining under water bodies. 展开更多
关键词 Longwall mining fractured zone Mining under water body Overburden aquifer
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Nanoscale Morphology in Tensile Fracture of a Brittle Amorphous Ribbon
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作者 Xifeng LI. Kaifeng ZHANG Guofeng WANG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2008年第5期745-749,共5页
The paper reports on the observation of nanoscale morphology on the tensile fracture surface of a brittle amorphous Fe-based ribbon. The formation of nanoscale damage cavity structure is a main characteristic morpholo... The paper reports on the observation of nanoscale morphology on the tensile fracture surface of a brittle amorphous Fe-based ribbon. The formation of nanoscale damage cavity structure is a main characteristic morphology on the fracture surfaces. Approaching the ribbon boundary, these damage cavities assemble and form the nanoscale periodic corrugations, which are neither Wallner lines nor crack front waves. The periodic corrugations result from the interactions between the reflected elastic waves by the boundaries of amorphous ribbon and the stress fields of the crack tip. 展开更多
关键词 Nanoscale periodic corrugation Damage cavity Tensile fracture Brittle amorphous ribbon
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RHEOLOGICAL FRACTURE ANALYSIS OF CABLE BY CONSIDERING THE SECOND ORDER EFFECTS OF RANDOM SLACK
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作者 Yuan Longwei(Research Institute of Rheological Mechanics,Xiangtan University,Hunan 411105) 《Acta Mechanica Solida Sinica》 SCIE EI 1995年第4期314-326,共13页
In this paper we consider the cable as a bundle consisting of x sub-bundles, with m parallel tension members per sub-bundle, and the tension members themselves are polymeric yarns impregnated with a resin matrix. The ... In this paper we consider the cable as a bundle consisting of x sub-bundles, with m parallel tension members per sub-bundle, and the tension members themselves are polymeric yarns impregnated with a resin matrix. The nonfailad members at any instant must share an applied system load according to some rule, since there is a clearly expressed dependence of the fracture on the duration on the duration and character of the loading. So then, the fracture of cable is a process of nonlinear dynamic evolution, which accommodates to the non-equilibrium thermodynamics of irreversible processes by itself. Let us assume that the polymeric yarns art as viscoelastic solid, under certain probabilistic assumptions, according to the principles of rheology of bodies with defects, the relationship between the single member loading and failure and the bundle loading are investigated. It can be shown that the bundle failure time is asymptotically normally distributed as the number of members grows large. After a study of the second order effects of random slack, it is known that the asymptotic mean and variance are functions of the parameters of loading and single member theological behavior. Hence the loss in the asymptotic bundle strength mean brought about by random member and sub-bundle slack, L(s), and the loss in the asymptotic bundle strength variance caused by random member slack, Delta(s), are determined. And finally, if is known that the asymptotic time of failure can make up a considerable part of the fracture of cable, and the fracture of cable is a time-dependent process of rheological fracture. 展开更多
关键词 CABLE BUNDLE random slack rheological fracture rheology of bodies with defects
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Incidental echocardiographic finding:Fractured inferior vena cava filter
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作者 Bhradeev Sivasambu Deepa Kabirdas Assad Movahed 《World Journal of Clinical Cases》 SCIE 2017年第4期148-152,共5页
Inferior vena cava filters have gained increasing popularity in recent decades and knowledge on rare complications becomes vital to practicing physicians. A 30-year-old African American male with diabetes mellitus, hy... Inferior vena cava filters have gained increasing popularity in recent decades and knowledge on rare complications becomes vital to practicing physicians. A 30-year-old African American male with diabetes mellitus, hypertension, end-stage renal disease, history of deep venous thrombosis and placement of venacaval filter who was seen in the cardiology clinic for cardiac risks stratification prior to renal transplant. Patient denied any cardiac symptoms. A transthoracic echocardiogram was performed and showed two linear echoes bright densities in the right atrium and right ventricle embedded which was later found to be fractured filter struts by computed tomography. We discuss the various outcomes associated with nonretrieval of retrievable inferior vena cava filters. 展开更多
关键词 INFERIOR vena cava FILTER fractured INFERIOR vena cava FILTER CARDIAC FOREIGN body Metal in HEART INCIDENTAL echocardiographic finding
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Experimental test and theoretical calculation of the fracture height limit of gas pipe flow to Darcy flow
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作者 XIONG Yu FU Xitong +3 位作者 LI Qian SUN Zewei ZHANG Chun ZHANG Fei 《Petroleum Exploration and Development》 CSCD 2022年第3期614-624,共11页
Low-speed flow experiments in which ultra-fine copper tubes are used to simulate micro-fractures in carbonate strata are conducted to analyze the variations of gas flow state in fractures of different fracture heights... Low-speed flow experiments in which ultra-fine copper tubes are used to simulate micro-fractures in carbonate strata are conducted to analyze the variations of gas flow state in fractures of different fracture heights,determine flow state transition limit and transition interval,and establish the calculation method of flow state transition limit.The results show that the ideal Hagen-Poiseuille flow is the main form of gas flow in large fractures.Due to the decrease of fracture height,the gas flow in the fracture changes from Hagen-Poiseuille flow with ideal smooth seam surface to non-Hagen-Poiseuille flow,and the critical point of the transition is the boundary of flow state transition.After the fracture height continues to decrease to a certain extent below the boundary of the flow state transition fracture height,the form of gas flow gradually changes to the ideal Darcy flow,thus the transition interval of the gas flow state in the closing process of fracture can be determined.Based on the three-dimensional microconvex body scanning of the fracture surface,the material properties of fracture and properties of fluid in the fracture,a method for calculating the boundary of flow state transition is established.The experimental test and theoretical calculation show that the limit of the fracture height for the transition from pipe flow to Darcy flow is about twice the sum of the maximum height of the microconvex bodies on the upper and lower sides of the fracture. 展开更多
关键词 carbonate gas reservoir fracture height flow experiment flow limit Hagen-Poiseuille flow Darcy flow microconvex body
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An Unusual Foreign Body in the Nasal Cavity
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作者 Rameshbabu Kalyanasundaram Ramanathan Thirunavukkarasu +1 位作者 Ganeshkumar Balasubramaniam Hemalatha Palaniappan 《International Journal of Otolaryngology and Head & Neck Surgery》 2014年第5期267-270,共4页
The nasal foreign bodies are commonly seen up to the age of 12. This is a rare case of a 10-year-old boy who had playfully introduced an almost straight sharp rigid iron wire of length 13 cm into his nose. The patient... The nasal foreign bodies are commonly seen up to the age of 12. This is a rare case of a 10-year-old boy who had playfully introduced an almost straight sharp rigid iron wire of length 13 cm into his nose. The patient presented with the foreign body protruding outside his nose. Radiological investigations revealed that the foreign body had hooked around the posterior end of the bony septum which was removed under endoscopic guidance. 展开更多
关键词 Foreign body Iron Wire in NOSE NASAL cavity EPISTAXIS
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Effect of successive irrigation of subarachnoid cavity on body temperature and cerebrospinal fluid-related index in suppurative meningitis model dogs
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作者 Yong Liu Guohou He +2 位作者 Yuanyuan Wang Xueqiang Chen Qibin Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第2期108-110,共3页
BACKGROUND: At present, suppurative meningitis is mainly treated through anti-infection with antibiotics, depressing encephalic pressure with mannitol , lowering body temperature with drugs , supporting treatment, et... BACKGROUND: At present, suppurative meningitis is mainly treated through anti-infection with antibiotics, depressing encephalic pressure with mannitol , lowering body temperature with drugs , supporting treatment, etc. However, Jt takes a long course of treatment and has poor therapeutic effect. Successive irrigation of subarachnoid cavity maybe have better effect on suppurative meningitis.OBJECTIVE: We compared the successive irrigation of subbarachnoid cavity with routine therapeutic methods to observe the effect of successive irrigation of subarachnoid cavity on the body temperature, cerebrospinal fluid pressure, the number of white blood cell and the level of protein of suppurative meningitis dogs. DESIGN: A randomized and controlled animal experiment SETTING: Institute of Neuroscience, Taihe Hospital Affiliated to Yunyang Medical College MATERIALS: Totally 17 healthy adult male Beagle dogs, of common grade, weighing 9 to 10 kg, were involved in the experiment, and raised in the 20 ℃ temperature with relative humidity of 50% for 1 week. They were randomized into 3 groups: normal group (n=5), control group (n=5) and irrigation group (n=6). Artificial cerebrospinal fluid was prepared according to the level of glucose and chloride of cerebrospinal fluid of normal dogs, and then it was sterilized with high pressure. METHODS : This experiment was carried out in the experimental animal center of Yunyang Medical College from April to August 2001. ① After the dogs were anesthetized,1 mL fresh staphylococcus aureus liquid [(1.5-1.6)× 10^9 L 1] was injected into medullary cistern to establish suppurative meningitis models. ② After models were successfully established, intravenous drip infusion of 1.2 ×10^6 U/(kg.d), muscular injection of sulfadiazine sodium of 100 mg/(kg.d )and intravenous injection of 200 g/L mannitol of 5 g/(kg .time) for 3 times a day were performed in the control group. The irrigation of subarachnoid meningitis was conducted in the irrigation group besides the routine treatments in the control group: Artificial cerebrospinal fluid was successively injected into the epidural catheter in the waist part. The mixtures of artificial cerebrospinal fluid and inflammatory cerebrospinal fluid flowed out incessantly from epidural catheter of medullary cistern. Irrigation was ended 48 hours later. Dogs were routinely raised in the control group. ③ From the first day after being modeled to the 14^th day after treatment, the rectal temperatures were daily measured in the morning, at noon and in the evening respectively, then the mean temperatures were calculated. From the 2^nd day after being modeled to the 14^th day after treatment, puncture at waist was given once, and the cerebrospinal fluid pressure, the number of white blood cells and the level of protein were measured. MAIN OUTCOME MEASURES : The body temperature, cerebrospinal fluid pressure, the number of white blood cells and the level of protein were measured on suppurative meningitis model dogs. RESULTS" Totally 17 Beagle dogs were involved in this study.①The body temperatures of dogs were significantly reduced in the control group and in irrigation group on the 1^st day after treatment and lower than suppurative meningitis model dogs on the 2^nd day after being modeled (P 〈 0.05). The body temperatures were gradually decreased in control group from the 2^nd day after being modeled to the 14^th day after treatment (P 〈 0.01), but were significantly higher than those of dogs in normal group on the 14^th day after treatment (P 〈 0.05). The body temperatures of dogs were gradually decreased in irrigation group on the 2^nd day or 3^rd day after treatment (P 〈 0.01) and then were close to the normal body temperature on the 14^th day after treatment. ②There was the same cerebrospinal fluid pressure in control group as in irrigation group on the 2^nd day after being modeled (P 〉 0.05), but significantly decreased in two groups from the 1s' day or 2^nd day after treatment (P 〈 0.01), and cerebrospinal fluid pressure was close to the normal level in irrigation group. Although the cerebrospinal fluid pressure raised a little on the 3^rd day or 4^th day after treatment in the irrigation group (P〈 0.05), but recovered to the normal level on the 9^th day after treatment again. It decreased slowly in the control group and still was sig- nificantly higher than normal group on the 14^hd day after treatment (P〈 0.01 ). ③No significant difference existed in number of white blood cell and the level of protein between control group and irrigation group on the 2^nd day following modeled. Both of them began to significantly decrease on the 1^st and 2^nd day after treatment (P 〈 0.01 ). Although the number of white blood cell and the level of protein rebounded a little in irrigation group 3 or 4 days after treatment (P〈 0.05), they were gradually decreased and recovered to normal levels on the 13^th day after treatment. The number of white blood cell and the level of protein slowly decreased in the control group compared with irrigation group and were still significantly higher than normal group on the 14^th day (P〈 0.01 ). EONELUSEON : Irrigation of subarachnoid cavity can decrease the body temperature, cerebrospinal fluid pressure, the number of white blood cells and the level of protein at early stage of suppurative meningitis, and the therapeutic effect is better than that of routine treatment. 展开更多
关键词 body Effect of successive irrigation of subarachnoid cavity on body temperature and cerebrospinal fluid-related index in suppurative meningitis model dogs
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