Static mechanical experiments were carried out on granite after and under different temperatures using an electro-hydraulic and servo-controlled material testing machine with a heating device. Variations in obvious fo...Static mechanical experiments were carried out on granite after and under different temperatures using an electro-hydraulic and servo-controlled material testing machine with a heating device. Variations in obvious form, stress-strain curve, peak strength, peak strain and elastic modulus with temperature were analyzed and the essence of rock failure modes was explored. The results indicate that, compared with granite after the high temperature treatment, the brittle-ductile transition critical temperature is lower, the densification stage is longer, the elastic modulus is smaller and the damage is larger under high temperature. In addition, the peak stress is lower and the peak strain is greater, but both of them change more obviously with the increase of temperature compared with that of granite after the high temperature treatment. Furthermore, the failure modes of granite after the high temperature treatment and under high temperature show a remarkable difference. Below 100 ℃, the failure modes of granite under both conditions are the same, presenting splitting failure. However, after 100 ℃, the failure modes of granite after the high temperature treatment and under high temperature present splitting failure and shear failure, respectively.展开更多
We aimed to study the appropriate posture of peripherally inserted central catheter (PICC) patients, to reduce the incidence of internal jugular vein heterotopia. Methods: From 2009 to 2013, a total of 290 cases wi...We aimed to study the appropriate posture of peripherally inserted central catheter (PICC) patients, to reduce the incidence of internal jugular vein heterotopia. Methods: From 2009 to 2013, a total of 290 cases with PICC were enrolled in our study. They were divided into two groups. The patients in control group took regular position, which mean pros- tration, upper limb of tube side was abduction 90°, head moved to puncture side in order to block the internal jugular vein. On the basis of conventional body position putting, posture of patients in observation group was improved, the head remain neutral, and had 180° angle with trunk longitudinal axis, not favor any side. After ensuring the upper limb abduction, had 90° angle with the trunk, then catheter was inserted slowly. The jugular venous catheter heterotopia rate was judged by X.ray results. Results: The jugular venous catheter heterotopia rate of control group and observation was 12.8% and 0.68%, respectively. The difference between two groups was statistically significant (P 〈 0.01). Conclusion: The body posture improvement can prevent discomfort of patients and reduce the jugular venous catheter heterotopia rate of PICC.展开更多
The district heating company "Rigas siltums" operates biomass fuelled boiler in Riga city. Three systems consisting ofbiomass boilers having a comparatively similar heat capacity and particle abatement units like mu...The district heating company "Rigas siltums" operates biomass fuelled boiler in Riga city. Three systems consisting ofbiomass boilers having a comparatively similar heat capacity and particle abatement units like multicyclons, electrostatic precipitators and flue gas condensers are compared. The main goal of the study is to evaluate the boiler plant as a system where solid particles are both emitted and caught. The results show that, the particulate matter can be efficiently trapped from flue gases by the particle abatement technologies, and the electrostatic precipitator with sufficiently large collection surfaces is able to provide appropriate flue gas treatment of the particulate matter in the biomass boilers also without pre-cleaning of the flue gas in multieyelons.展开更多
Electrospinning is firstly used to one-pot synthesis of Li3VO4@C nanofibers in a large scale. Although with the presence of organic sources in synthesis process, the pure phase Li3VO4 with superior nanofibrous morphol...Electrospinning is firstly used to one-pot synthesis of Li3VO4@C nanofibers in a large scale. Although with the presence of organic sources in synthesis process, the pure phase Li3VO4 with superior nanofibrous morphology is still successfully obtained through adjusting different heat treatment processes and different vanadium sources. The prepared Li3VO4@C nanofibers exhibit a unique structure in which nanosized Li3VO4 particles are uniformly embedded in amorphous carbon matrix. Compared with LiBVO4/C powder, Li3VO4@C nanofibers display enhanced reversible capacity of 451 mAhg^-1 at 40mAg^-1 with an increased initial coulombic efficiency of 82.3%, and the capacity can remain at 394 mAh g ^-1 after 100 cycles. This superior electrochemical performance can be attributed to its unique structure which ensures a high reactivity by nanosized Li3VO4, more stable electrode/electrolyte interface by carbon encapsulation, improved electronic conductivity and buffered volume changes by flexible carbon matrix. The electrospinning technology provides an effective method to obtain high performance Li3VO4 as a promising anode material for lithium-ion batteries.展开更多
When the envelope of the conducting strips for the input transducer of magnetostatic surface wave(MSSW) device is designed according to the wavelet-function envelope,the impulse-response function of the input transduc...When the envelope of the conducting strips for the input transducer of magnetostatic surface wave(MSSW) device is designed according to the wavelet-function envelope,the impulse-response function of the input transducer for MSSW device is equal to the wavelet function,so that single-scale wavelet-transform processor of MSSW type is fabricated.First,according to the envelope function of the wavelet,the length function of the conducting strips is defined,then,the lengths of the conducting strips can be calculated from the length function of the conducting strips,finally,the input transducer can be designed according to the lengths and widths for the conducting strips.The compensation method of the insertion loss for single-scale wavelet trans-form processor of MSSW type is also given in the paper.When the output end of single-scale wavelet transform processor of MSSW type is connected to the amplifier,its insertion loss can be compensated.展开更多
基金Projects(51304241,11472311,51322403)supported by the National Natural Science Foundation of ChinaProject(2015CX005)supported by Innovation Driven Plan of Central South University,China+1 种基金Project(2016zzts456)supported by Independent Exploration and Innovation Foundation of Central South University,ChinaProject(2015CB060200)supported by the National Basic Research Program of China
文摘Static mechanical experiments were carried out on granite after and under different temperatures using an electro-hydraulic and servo-controlled material testing machine with a heating device. Variations in obvious form, stress-strain curve, peak strength, peak strain and elastic modulus with temperature were analyzed and the essence of rock failure modes was explored. The results indicate that, compared with granite after the high temperature treatment, the brittle-ductile transition critical temperature is lower, the densification stage is longer, the elastic modulus is smaller and the damage is larger under high temperature. In addition, the peak stress is lower and the peak strain is greater, but both of them change more obviously with the increase of temperature compared with that of granite after the high temperature treatment. Furthermore, the failure modes of granite after the high temperature treatment and under high temperature show a remarkable difference. Below 100 ℃, the failure modes of granite under both conditions are the same, presenting splitting failure. However, after 100 ℃, the failure modes of granite after the high temperature treatment and under high temperature present splitting failure and shear failure, respectively.
文摘We aimed to study the appropriate posture of peripherally inserted central catheter (PICC) patients, to reduce the incidence of internal jugular vein heterotopia. Methods: From 2009 to 2013, a total of 290 cases with PICC were enrolled in our study. They were divided into two groups. The patients in control group took regular position, which mean pros- tration, upper limb of tube side was abduction 90°, head moved to puncture side in order to block the internal jugular vein. On the basis of conventional body position putting, posture of patients in observation group was improved, the head remain neutral, and had 180° angle with trunk longitudinal axis, not favor any side. After ensuring the upper limb abduction, had 90° angle with the trunk, then catheter was inserted slowly. The jugular venous catheter heterotopia rate was judged by X.ray results. Results: The jugular venous catheter heterotopia rate of control group and observation was 12.8% and 0.68%, respectively. The difference between two groups was statistically significant (P 〈 0.01). Conclusion: The body posture improvement can prevent discomfort of patients and reduce the jugular venous catheter heterotopia rate of PICC.
文摘The district heating company "Rigas siltums" operates biomass fuelled boiler in Riga city. Three systems consisting ofbiomass boilers having a comparatively similar heat capacity and particle abatement units like multicyclons, electrostatic precipitators and flue gas condensers are compared. The main goal of the study is to evaluate the boiler plant as a system where solid particles are both emitted and caught. The results show that, the particulate matter can be efficiently trapped from flue gases by the particle abatement technologies, and the electrostatic precipitator with sufficiently large collection surfaces is able to provide appropriate flue gas treatment of the particulate matter in the biomass boilers also without pre-cleaning of the flue gas in multieyelons.
基金supported by the National Natural Science Foundation of China (21571073, 51302099, 51472097)the Ministry of Science and Technology of China (2015CB932600)+2 种基金the Hubei Provincial Natural Science Foundation (2016CFA031)the Program for Huazhong University of Science and Technology (HUST) Interdisciplinary Innovation Team (2015ZDTD038)the Fundamental Research Funds for the Central University (2017KFKJXX007)
文摘Electrospinning is firstly used to one-pot synthesis of Li3VO4@C nanofibers in a large scale. Although with the presence of organic sources in synthesis process, the pure phase Li3VO4 with superior nanofibrous morphology is still successfully obtained through adjusting different heat treatment processes and different vanadium sources. The prepared Li3VO4@C nanofibers exhibit a unique structure in which nanosized Li3VO4 particles are uniformly embedded in amorphous carbon matrix. Compared with LiBVO4/C powder, Li3VO4@C nanofibers display enhanced reversible capacity of 451 mAhg^-1 at 40mAg^-1 with an increased initial coulombic efficiency of 82.3%, and the capacity can remain at 394 mAh g ^-1 after 100 cycles. This superior electrochemical performance can be attributed to its unique structure which ensures a high reactivity by nanosized Li3VO4, more stable electrode/electrolyte interface by carbon encapsulation, improved electronic conductivity and buffered volume changes by flexible carbon matrix. The electrospinning technology provides an effective method to obtain high performance Li3VO4 as a promising anode material for lithium-ion batteries.
基金supported by the National Natural Science Foundation of China (Grant No 60976058)
文摘When the envelope of the conducting strips for the input transducer of magnetostatic surface wave(MSSW) device is designed according to the wavelet-function envelope,the impulse-response function of the input transducer for MSSW device is equal to the wavelet function,so that single-scale wavelet-transform processor of MSSW type is fabricated.First,according to the envelope function of the wavelet,the length function of the conducting strips is defined,then,the lengths of the conducting strips can be calculated from the length function of the conducting strips,finally,the input transducer can be designed according to the lengths and widths for the conducting strips.The compensation method of the insertion loss for single-scale wavelet trans-form processor of MSSW type is also given in the paper.When the output end of single-scale wavelet transform processor of MSSW type is connected to the amplifier,its insertion loss can be compensated.