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Cumulative effects of excess high-normal alanine aminotransferase levels in relation to new-onset metabolic dysfunction-associated fatty liver disease in China 被引量:7
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作者 Jing-Feng Chen Zhuo-Qing Wu +5 位作者 Hao-Shuang Liu Su Yan You-Xiang Wang Miao Xing Xiao-Qin Song Su-Ying Ding 《World Journal of Gastroenterology》 SCIE CAS 2024年第10期1346-1357,共12页
BACKGROUND Within the normal range,elevated alanine aminotransferase(ALT)levels are associated with an increased risk of metabolic dysfunction-associated fatty liver disease(MAFLD).AIM To investigate the associations ... BACKGROUND Within the normal range,elevated alanine aminotransferase(ALT)levels are associated with an increased risk of metabolic dysfunction-associated fatty liver disease(MAFLD).AIM To investigate the associations between repeated high-normal ALT measurements and the risk of new-onset MAFLD prospectively.METHODS A cohort of 3553 participants followed for four consecutive health examinations over 4 years was selected.The incidence rate,cumulative times,and equally and unequally weighted cumulative effects of excess high-normal ALT levels(ehALT)were measured.Cox proportional hazards regression was used to analyse the association between the cumulative effects of ehALT and the risk of new-onset MAFLD.RESULTS A total of 83.13%of participants with MAFLD had normal ALT levels.The incidence rate of MAFLD showed a linear increasing trend in the cumulative ehALT group.Compared with those in the low-normal ALT group,the multivariate adjusted hazard ratios of the equally and unequally weighted cumulative effects of ehALT were 1.651[95%confidence interval(CI):1.199-2.273]and 1.535(95%CI:1.119-2.106)in the third quartile and 1.616(95%CI:1.162-2.246)and 1.580(95%CI:1.155-2.162)in the fourth quartile,respectively.CONCLUSION Most participants with MAFLD had normal ALT levels.Long-term high-normal ALT levels were associated with a cumulative increased risk of new-onset MAFLD. 展开更多
关键词 Metabolic dysfunction-associated fatty liver disease high-normal alanine aminotransferase level Cumulative effect Cox proportional hazards regression Cohort study
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Electrode/Electrolyte Interfacial Chemistry Modulated by Chelating Effect for High-Performance Zinc Anode 被引量:1
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作者 Chuanlin Li Guangmeng Qu +2 位作者 Xixi Zhang Chenggang Wang Xijin Xu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期93-99,共7页
Although Zn metal has been regarded as the most promising anode for aqueous batteries,its practical application is still restricted by side reactions and dendrite growth.Herein,an in-situ solid electrolyte interphase(... Although Zn metal has been regarded as the most promising anode for aqueous batteries,its practical application is still restricted by side reactions and dendrite growth.Herein,an in-situ solid electrolyte interphase(SEI)film formed on the interface of electrode/electrolyte during the plating/stripping of zinc anodes by introducing trace amounts of multidentate ligand sodium diethyldithiocarbamate(DDTC)additive into 1 M ZnSO_(4).The synergistic effect of in-situ solid electrolyte interphase forming and chelate effect endows Zn^(2+)with uniform and rapid interface-diffusion kinetics against dendrite growth and surface side reactions.As a result,the Zn anode in 1 M ZnSO_(4)+DDTC electrolytes displays an ultra-high coulombic efficiency of 99.5%and cycling stability(more than 2000 h),especially at high current density(more than 600 cycles at 40 mA cm^(-2)).Moreover,the Zn//MnO_(2)full cells in the ZnSO_(4)+DDTC electrolyte exhibit outstanding cyclic stability(with 98.6%capacity retention after 2000 cycles at 10 C).This electrode/electrolyte interfacial chemistry modulated strategy provides new insight into enhancing zinc anode stability for high-performance aqueous zinc batteries. 展开更多
关键词 chelating effect in-situ SEI ultra-high current density Zn anodes
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Design and Implementation of a High-Sensitivity Magnetic Sensing System Based on GMI Effect
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作者 Wenzhu Wu Ming Xu +4 位作者 Changlin Han Junquan Tang Jia Xu Lin Xu Mingxin Qin 《Journal of Beijing Institute of Technology》 EI CAS 2024年第3期237-247,共11页
A high-sensitivity magnetic sensing system based on giant magneto-impedance(GMI)effect is designed and fabricated.The system comprises a GMI sensor equipped with a gradient probe and an signal acquisition and processi... A high-sensitivity magnetic sensing system based on giant magneto-impedance(GMI)effect is designed and fabricated.The system comprises a GMI sensor equipped with a gradient probe and an signal acquisition and processing module.A segmented superposition algorithm is used to increase target signal and reduce the random noise.The results show that under unshielded,room temperature conditions,the system achieves successful detection of weak magnetic fields down to 2 pT with a notable sensitivity of 1.84×10^(8)V/T(G=1000).By applying 17 overlays,the segmented superposition algorithm increases the power proportion of the target signal at 31 Hz from6.89%to 45.91%,surpassing the power proportion of the 2 Hz low-frequency interference signal.Simultaneously,it reduces the power proportion of the 20 Hz random noise.The segmented superposition process effectively cancels out certain random noise elements,leading to a reduction in their respective power proportions.This high-sensitivity magnetic sensing system features a simple structure,and is easy to operate,making it highly valuable for both practical applications and broader dissemination. 展开更多
关键词 high-SENSITIVITY magnetic field sensing system GMI effect segmented superposition algorithm
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OML:an online multi-particle locating method for high-resolution single-event effects studies
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作者 Yan-Hao Jia Jian-Wei Liao +5 位作者 Hai-Bo Yang Qi-Hao Duan Long-Jie Wang Jiang-Yong Du Hong-Lin Zhang Cheng-Xin Zhao 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第11期61-72,共12页
Identifying sensitive areas in integrated circuits susceptible to single-event effects(SEE)is crucial for improving radiation hardness.This study presents an online multi-track location(OML)framework to enhance the hi... Identifying sensitive areas in integrated circuits susceptible to single-event effects(SEE)is crucial for improving radiation hardness.This study presents an online multi-track location(OML)framework to enhance the high-resolution online trajectory detection for the Hi’Beam-SEE system,which aims to localize SEE-sensitive positions on the IC at the micrometer scale and in real time.We employed a reparameterization method to accelerate the inference speed,merging the branches of the backbone of the location in the deployment scenario.Additionally,we designed an irregular convolution kernel,an attention mechanism,and a fused loss function to improve the positioning accuracy.OML demonstrates exceptional realtime processing capabilities,achieving a positioning accuracy of 1.83μm in processing data generated by the Hi’Beam-SEE system at 163 frames per second per GPU. 展开更多
关键词 Single-event effects Integrated circuits Silicon pixel Sensors Artificial intelligence Gaseous detector
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Magnetic and magnetocaloric effect of Er_(20)Ho_(20)Dy_(20)Cu_(20)Ni_(20)high-entropy metallic glass
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作者 于世霖 田路 +4 位作者 王俊峰 赵新国 李达 莫兆军 李昺 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期602-606,共5页
Er_(20)Ho_(20)Dy_(20)Cu_(20)Ni_(20)high-entropy metallic glass exhibited excellent magnetic refrigeration material with a wide temperature range and high refrigeration capacity(RC)was reported.Er_(20)Ho_(20)Dy_(20)Cu_... Er_(20)Ho_(20)Dy_(20)Cu_(20)Ni_(20)high-entropy metallic glass exhibited excellent magnetic refrigeration material with a wide temperature range and high refrigeration capacity(RC)was reported.Er_(20)Ho_(20)Dy_(20)Cu_(20)Ni_(20)high-entropy metallic glass was observed with typical spin glass behavior around 15.5 K.In addition,we find that the magnetic entropy change(-△S_(M))originates from the sample undergoing a ferromagnetic(FM)to paramagnetic(PM)transition around 20 K.Under a field change from 0 T to 7 T,the value of maximum magnetic entropy change(-△S_(M)^(max))reaches 12.5 J/kg·K,and the corresponding value of RC reaches 487.7 J/kg in the temperature range from 6 K to 60 K.The large RC and wide temperature range make the Er_(20)Ho_(20)Dy_(20)Cu_(20)Ni_(20)high-entropy metallic glass be a promising material for application in magnetic refrigerators. 展开更多
关键词 magnetic materials magnetocaloric effect high-entropy metallic glass magnetic refrigeration large refrigeration capacity
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Efficient activation of the Co/SBA-15catalyst by high-frequency AC-DBD plasma thermal effects for toluene removal
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作者 李越 姜楠 +5 位作者 刘政妍 秦亮 彭邦发 王荣刚 孙玉荣 李杰 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第8期84-94,共11页
Dielectric barrier discharge(DBD)plasma excited by a high-frequency alternating-current(AC)power supply is widely employed for the degradation of volatile organic compounds(VOCs).However,the thermal effect generated d... Dielectric barrier discharge(DBD)plasma excited by a high-frequency alternating-current(AC)power supply is widely employed for the degradation of volatile organic compounds(VOCs).However,the thermal effect generated during the discharge process leads to energy waste and low energy utilization efficiency.In this work,an innovative DBD thermally-conducted catalysis(DBD-TCC)system,integrating high-frequency AC-DBD plasma and its generated thermal effects to activate the Co/SBA-15 catalyst,was employed for toluene removal.Specifically,Co/SBA-15 catalysts are closely positioned to the ground electrode of the plasma zone and can be heated and activated by the thermal effect when the voltage exceeds 10 k V.At12.4 k V,the temperature in the catalyst zone reached 261℃ in the DBD-TCC system,resulting in an increase in toluene degradation efficiency of 17%,CO_(2)selectivity of 21.2%,and energy efficiency of 27%,respectively,compared to the DBD system alone.In contrast,the DBD thermally-unconducted catalysis(DBD-TUC)system fails to enhance toluene degradation due to insufficient heat absorption and catalytic activation,highlighting the crucial role of AC-DBD generated heat in the activation of the catalyst.Furthermore,the degradation pathway and mechanism of toluene in the DBD-TCC system were hypothesized.This work is expected to provide an energy-efficient approach for high-frequency AC-DBD plasma removal of VOCs. 展开更多
关键词 high-frequency alternating-current power thermal effect dielectric barrier discharge toluene degradation Co/SBA-15 catalysts
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Analysis of the Effect of High-Dose Segmental Citrate Anticoagulation in High Flux Hemodialysis
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作者 Xubo Fu 《Journal of Clinical and Nursing Research》 2024年第5期95-99,共5页
Objective:To analyze the clinical effect of high-dose citrate in segmental extracorporeal anticoagulation for high-throughput hemodialysis.Methods:The subjects included in this study were admitted to the hospital for ... Objective:To analyze the clinical effect of high-dose citrate in segmental extracorporeal anticoagulation for high-throughput hemodialysis.Methods:The subjects included in this study were admitted to the hospital for maintenance hemodialysis treatment from January 2021 to January 2023.All patients had a high risk of bleeding and received 4%trisodium citrate anticoagulant treatment,administered at a rate of 200 mL/h before and after the dialyzer.The anticoagulant effects achieved by the patients were observed and analyzed.Results:The total number of patients who received high-dose segmented citrate extracorporeal anticoagulation dialysis treatment was 50,with each patient undergoing 100 treatments.During the treatment,2 patients had to end the treatment early due to transmembrane pressure exceeding 30 mmHg and an increase in venous pressure exceeding 250 mmHg;the treatment times for these patients were 20 minutes and 200 minutes,respectively.The remaining patients successfully completed the 4-hour treatment.Blood pH and calcium ion concentration in the venous pot were monitored.It was observed that before dialysis,after 2 hours of dialysis,and at the end of dialysis,the blood pH of the patients remained within a relatively normal range.Although some patient levels changed after dialysis,they remained within the normal range.No adverse reactions(such as numbness of the limbs or convulsions)were observed during the anticoagulant treatment.Conclusion:Administering 4%trisodium citrate at a rate of 200 mL/h before and after the dialyzer achieves a good anticoagulant effect,maintains the patient’s blood gas levels within the normal range at the end of dialysis,and causes no adverse reactions. 展开更多
关键词 High dose Segmented citrate High flux HEMODIALYSIS Anticoagulation effect
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Effect of La_2O_3/Ce O_2 particle size on high-temperature oxidation resistance of electrodeposited Ni-La_2O_3/Ce O_2 composites 被引量:4
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作者 孟君晟 吉泽升 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3571-3577,共7页
Ni-La2O3/CeO2 composite films were prepared by electrodeposition from a nickel sulfate bath containing certain content of micrometer and nanometer La2O3/CeO2 particles. The effect of La2O3 or CeO2 particle size on the... Ni-La2O3/CeO2 composite films were prepared by electrodeposition from a nickel sulfate bath containing certain content of micrometer and nanometer La2O3/CeO2 particles. The effect of La2O3 or CeO2 particle size on the oxidation resistance of the electrodeposited Ni-La2O3/CeO2 composites in air at 1000 °C was studied. The results indicate that, compared with the electrodeposited Ni-film, Ni-La2O3/CeO2 composites exhibit a superior oxidation resistance due to the codeposited La2O3 or CeO2 particles blocking the outward diffusion of nickel. Moreover, compared with nanoparticles, La2O3 or CeO2 microparticles have stronger effect because La2O3 or CeO2 microparticles also act as a diffusion barrier layer at the onset of oxidation. 展开更多
关键词 Ni-based composite ELECTRODEPOSITION high-temperature oxidation LA2O3 CEO2 reactive element effect oxidation mechanism
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TRANSVERSE VELOCITY ESTIMATION BASED ON HIGH-ORDER DOPPLER EFFECT OF MOVING OBJECT 被引量:1
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作者 张兴敢 柏业超 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第3期224-228,共5页
The one-order phase of the echo changes if there is relative radial moving between the object and the radar, i.e. , the Doppler effect. The Doppler effect is widely used in radar signal processing. The transverse moti... The one-order phase of the echo changes if there is relative radial moving between the object and the radar, i.e. , the Doppler effect. The Doppler effect is widely used in radar signal processing. The transverse motion of the object cannot change the one-order phase of the echo, but the high-order phase. The high-order Doppler effect of the transverse moving target is presented and a new algorithm for obtaining the transverse velocity is given. The scalar velocity of a target moving steadily in any direction can be calculated with one-order and two-order items of the echo phase. The calculating method and simulating results are given. As the transverse speed is 900 km/h, the speed calculation error is less than 0. 06% if SNR of echo signal is higher than 0 dB. 展开更多
关键词 Doppler effect curve fitting transverse movement phase difference
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High-level Stark Effect and Spectrum of Spherical Nanometer System 被引量:1
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作者 吴强 龙晓霞 郑瑞伦 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第5期608-614,622,共8页
In the electric field and layer-to-layer interaction energy, the law of split-level of high-level Stark effect of spherical nanometer system is explored as well as the frequency of spectrum, intensity and size effect ... In the electric field and layer-to-layer interaction energy, the law of split-level of high-level Stark effect of spherical nanometer system is explored as well as the frequency of spectrum, intensity and size effect of coefficient of spontaneous radiation. Taking three layers CdS/HgS spherical nanometer system as an example, the influence of the electric field and layer-to- layer interaction energy is explored on Stark effect and spectrum. The results show that in the Stark effect system, the energy level is split based on 1, 3, ..., (2n-1), when it is in the electric field only, similar to the hydrogen atoms; and in the electric field and layer-to-layer interaction, it is split based on 1, 4, ~ -., n2; with the quantum transition, the frequency of the spectrum decreases with the increasing size of the system; apart from a few spectral lines, the intensity of most spectral lines will decreased as the size increases; while the coefficient of spontaneous radiation will increase with the increasing size; the electric field will cause the changes of spectrum frequency; its spectrum frequency shift is proportional to the square of the electric field intensity; apart from a few spectral lines, the frequency shift of spectral lines that is caused by the electric field and layer-to-layer interaction will decrease as the size increases; the interaction will make the level of electronic energy level lower slightly (the order of magnitude is between 10-7-10-9 eV), the slightly increased spectrum intensity and the slightly increased value of coefficient of spontaneous radiation, but it will not influence the frequency of spectrum, intensity, and the trend that coefficient of spontaneous radiation changes with the size; when the size is smaller, the layer-to-layer interaction effect will be significant. 展开更多
关键词 Layer-to-layer interaction energy CdS/HgS/CdS spherical nanometer system Stark effect Frequency shift of spectral line Coefficient of spontaneous radiation
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The effect of high-temperature annealing on LaFe_(11.5)Si_(1.5) and the magneto-caloric properties of La_(1-x)Ce_xFe_(11.5)Si_(1.5) compounds 被引量:7
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作者 CHEN Xiang CHEN Yungui TANG Yongbo 《Rare Metals》 SCIE EI CAS CSCD 2011年第4期343-347,共5页
The powder X-ray diffraction patterns of LaFell.sSil.5 compounds annealed at different high temperatures from 1323 K (5 h) to 1623 K (2 h) show that a large amount of 1:13 phase begins to form in LaFell.sSiL5 com... The powder X-ray diffraction patterns of LaFell.sSil.5 compounds annealed at different high temperatures from 1323 K (5 h) to 1623 K (2 h) show that a large amount of 1:13 phase begins to form in LaFell.sSiL5 compound annealed at 1423 K (5 h). In the temperature range from 1423 to 1523 K, ^-Fe and LaFeSi phases rapidly decrease to form 1:13 phase. LaFeSi phase is rarely observed, and the most amount of 1:13 phase is obtained in the compound annealed at 1523 K (5 h). With the annealing temperature increasing to 1573 and 1623 K, LaFeSi is detected again in the LaFell.sSil.s compound. According to the results of annealing at different high-temperatures, the Lal-xCexFelt.sSit.5 compounds are annealed at high temperatures of 1373 K (2 h) + 1523 K (5 h). The main phase is NaZn13-type phase, and the impurity is a small amount of et-Fe in Lal-xCexFexx.sSil.5 compounds with 0 〈 x 〈 0.35, and there is a large amount of CeaFe17 phase in Lao.sCeo.sFela.sSil.s. It indicates that the substitution of cerium atoms for La in LaFelLsSil.5 compounds has limit. At the same time, the substitution of Ce for La has large effect on magnetocaloric properties. With increasing Ce content from x = 0 to x = 0.35, the Curie temperature decreases linearly from 196 to 168 K, the magnetic entropy change increases from 16.5 to 57.3 J-kg-kK-1 in a low magnetic field change of 0-2 T, and the thermal hysteresis also increases from 3 K to 8 K. 展开更多
关键词 rare earth compounds high-temperature annealing magnetocaloric effect phase composition
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Damage effects and mechanism of the silicon NPN monolithic composite transistor induced by high-power microwaves 被引量:4
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作者 Hui Li Chang-Chun Chai +2 位作者 Yu-Qian Liu Han Wu in-Tang Yang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期633-639,共7页
A two-dimensional model of the silicon NPN monolithic composite transistor is established for the first time by utilizing the semiconductor device simulator, Sentaurus-TCAD. By analyzing the internal distributions of ... A two-dimensional model of the silicon NPN monolithic composite transistor is established for the first time by utilizing the semiconductor device simulator, Sentaurus-TCAD. By analyzing the internal distributions of electric field, current density, and temperature of the device, a detailed investigation on the damage process and mechanism induced by high-power microwaves (HPM) is performed. The results indicate that the temperature elevation occurs in the negative half-period and the temperature drop process is in the positive half-period under the HPM injection from the output port. The damage point is located near the edge of the base-emitter junction of T2, while with the input injection it exists between the base and the emitter of T2. Comparing these two kinds of injection, the input injection is more likely to damage the device than the output injection. The dependences of the damage energy threshold and the damage power threshold causing the device failure on the pulse-width are obtained, and the formulas obtained have the same form as the experimental equations, which demonstrates that more power is required to destroy the device if the pulse-width is shorter. Furthermore, the simulation result in this paper has a good coincidence with the experimental result. 展开更多
关键词 monolithic composite transistor high-power microwaves damage effects pulse-width effects
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Motion stability of high-speed maglev systems in consideration of aerodynamic effects: a study of a single magnetic suspension system 被引量:8
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作者 Han Wu Xiao-Hui Zeng Yang Yu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2017年第6期1084-1094,共11页
In this study, the intrinsic mechanism of aerodynamic effects on the motion stability of a high-speed maglev system was investigated. The concept of a critical speed for maglev vehicles considering the aerodynamic eff... In this study, the intrinsic mechanism of aerodynamic effects on the motion stability of a high-speed maglev system was investigated. The concept of a critical speed for maglev vehicles considering the aerodynamic effect is proposed. The study was carried out based on a single magnetic suspension system, which is convenient for proposing relevant concepts and obtaining explicit expressions. This study shows that the motion stability of the suspension system is closely related to the vehicle speed when aerodynamic effects are considered. With increases of the vehicle speed, the stability behavior of the system changes. At a certain vehicle speed,the stability of the system reaches a critical state, followed by instability. The speed corresponding to the critical state is the critical speed. Analysis reveals that when the system reaches the critical state, it takes two forms, with two critical speeds, and thus two expressions for the critical speed are obtained. The conditions of the existence of the critical speed were determined, and the effects of the control parameters and the lift coefficient on the critical speed were analyzed by numerical analysis. The results show that the first critical speed appears when the aerodynamic force is upward,and the second critical speed appears when the aerodynamic force is downward. Moreover, both critical speeds decrease with the increase of the lift coefficient. 展开更多
关键词 high-speed maglev system Critical speed Aerodynamic effect Motion stability
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Laboratory test on the combined cooling effect of L-shaped thermosyphons and thermal insulation on high-grade roadway construction in permafrost regions 被引量:3
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作者 YuanHong Dong,YuanMing Lai,MingYi Zhang,ShuangYang Li State Key Laboratory of Frozen Soil Engineering,Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences,Lanzhou,Gansu 730000,China. 《Research in Cold and Arid Regions》 2009年第4期307-315,共9页
With the completion of the Qinghai-Tibetan Railway,economic development of related areas has been greatly accelerated.This,in return,calls for building or upgrading more roadways,especially high-grade roadways.In cold... With the completion of the Qinghai-Tibetan Railway,economic development of related areas has been greatly accelerated.This,in return,calls for building or upgrading more roadways,especially high-grade roadways.In cold regions,the thawing of permafrost can induce settlement damage of and even failure to railway (or roadway) embankments.Thermosyphons (self-powered refrigera-tion devices that are used to help keep the permafrost cool) have proved effective in mitigating thaw settlement by maintaining the thermal stability of the embankments.However,for high-grade roadway embankments of great width,stabilizing or cooling ef-fects of traditional geotechnological measures may be limited.To enhance the cooling effect of thermosyphons,an L-shaped thermosyphon was designed.A laboratory test was carried out to study the combined cooling effect of the L-shaped thermosyphon and thermal insulation applying to roadbed construction.The angle between the evaporator and condenser sections of the L-shaped thermosyphon is 134 degrees,and the L-shaped thermosyphon was inserted into the soil at an angle of 5 degrees with the road surface.The tested results show that the L-shaped thermosyphon is effective in removing heat from a roadway in winter.When the ambient air temperature is lower than the soil temperature,the thermosyphon is active and extracts the heat in the soil around it.When the ambient air temperature is higher than the soil temperature,the thermosyphon is inactive,and no heat is in-jected into the soil through the L-shaped thermosyphon.Compared to embankments with straight thermosyphons,the inner parts of the embankments with L-shaped thermosyphons were significantly cooled.It is hoped that the present study would be useful to the application of L-shaped thermosyphons in the construction of high-grade roadways in cold regions. 展开更多
关键词 L-shaped thermosyphon thermal insulation cooling effect foundation soils high-grade roadway
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In vivo hyperthermia effect induced by high-intensity pulsed ultrasound 被引量:1
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作者 崔炜程 屠娟 +5 位作者 Hwang Joo-Ha 李倩 范庭波 章东 陈静海 陈伟中 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第7期352-358,共7页
Hyperthermia effects (39-44 ℃) induced by pulsed high-intensity focused ultrasound (HIFU) have been regarded as a promising therapeutic tool for boosting immune responses or enhancing drug delivery into a solid t... Hyperthermia effects (39-44 ℃) induced by pulsed high-intensity focused ultrasound (HIFU) have been regarded as a promising therapeutic tool for boosting immune responses or enhancing drug delivery into a solid tumor. However, previous studies also reported that the cell death occurs when cells are maintained at 43 ℃ for more than 20 minutes. The aim of this study is to investigate thermal responses inside in vivo rabbit auricular veins exposed to pulsed HIFU (1.17 MHz, 5300 W/cm2, with relatively low-duty ratios (0.2%-4.3%). The results show that: (1) with constant pulse repetition frequency (PRF) (e.g., 1 Hz), the thermal responses inside the vessel will increase with the increasing duty ratio; (2) a temperature elevation to 43 ℃ can be identified at the duty ratio of 4.3%; (3) with constant duty ratios, the change of PRF will not significantly affect the temperature measurement in the vessel; (4) as the duty ratios lower than 4.3%, the presence of microbubbles will not significantly enhance the thermal responses in the vessel, but will facilitate HIFU-induced inertial cavitation events. 展开更多
关键词 hyperthermia effects high-intensity focused ultrasound duty ratio ultrasound contrastagents
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Study on the sunny-shady slope effect on the subgrade of a high-speed railway in a seasonal frozen region 被引量:2
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作者 QingZhi Wang BoWen Tai +1 位作者 ZhenYa Liu JianKun Liu 《Research in Cold and Arid Regions》 CSCD 2015年第5期513-519,共7页
The temperature distributions of different parts of a subgrade were analyzed based on the results of three years of moni- toring data from the Harbin-Qiqihaer Passenger Dedicated Line, a high-speed railway, including ... The temperature distributions of different parts of a subgrade were analyzed based on the results of three years of moni- toring data from the Harbin-Qiqihaer Passenger Dedicated Line, a high-speed railway, including the slope toes, shoulders, and natural ground. The temperature variation with time and the maximum frozen depths showed that an obvious sun- ny-shady effect exists in the railway subgrade, which spans a seasonal frozen region. Development of frost heave is af- fected by the asymmetric temperature distribution. The temperature field and the maximum frozen depths 50 years after the subgrade was built were simulated with a mathematical model of the unsteady phase transition of the geothermal field. 展开更多
关键词 high-speed railway sunny-shady slope effect frost heave temperature field
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Numerical simulation of high-energy neutron radiation effect of scintillation fiber 被引量:2
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作者 MA Qingli TANG Shibiao ZOU Jiwei 《Nuclear Science and Techniques》 SCIE CAS CSCD 2008年第4期236-240,共5页
Due to their low cost,flexibility,and convenience for long distance data transfer,plastic scintillation fibers (PSF) have been increasingly used in building detectors or sensors for detecting various radiations and im... Due to their low cost,flexibility,and convenience for long distance data transfer,plastic scintillation fibers (PSF) have been increasingly used in building detectors or sensors for detecting various radiations and imaging. In this paper,GEANT4 Monte Carlo simulation tool was used to obtain some radiation effects of PSF under high-energy neutron irradiation. BCF-20,a plastic fiber material,produced by Saint-Gobain,was used in the simulation. The fiber consists of a core scintillating material of polystyrene and an acrylic outer cladding. Incident neutrons produce energy deposition in fiber through neutron induced recoil proton events. The relationships between energy deposition efficiency and fiber length,fiber radius and incident neutron energy are presented. The variation with those parameters and parameter selection are also analyzed. 展开更多
关键词 核爆炸 辐射作用 高能量中子 纤维
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Locating the cocktail and scaling-relation breaking effects of high-entropy alloy catalysts on the electrocatalytic volcano plot 被引量:4
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作者 Junxiang Chen Yaxin Ji 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第11期2889-2897,共9页
High entropy alloys(HEAs)have been the star materials in electrocatalysis research in recent years.One of their key features is the greatly increased multiplicity of active sites compared to conventional catalytic mat... High entropy alloys(HEAs)have been the star materials in electrocatalysis research in recent years.One of their key features is the greatly increased multiplicity of active sites compared to conventional catalytic materials.This increased multiplicity stimulates a cocktail effect and a scaling-relation breaking effect,and results in improved activity.However,the multiplicity of active sites in HEAs also poses new problems for mechanistic studies.One apparent problem is the inapplicability to HEA catalysts of the currently most popular mechanistic study method,which uses the electrocatalytic theoretical framework(ETF)based on the computational hydrogen electrode(CHE).The ETF uses a single adsorption energy to represent the catalyst,i.e.,a catalyst is represented by a'point'in the volcanic relationship.It naturally does not involve the multiplicity of active sites of a catalyst,and hence loses brevity in expressing the cocktail effect and scaling-relation breaking effect in HEA catalysis.This paper attempts to solve this inapplicability.Based on the fact that the adsorption energy distribution of HEAs is close to a normal distribution,the mean and variance of the adsorption energy distribution are introduced as descriptors of the ETF,replacing the original single adsorption energy.A quantitative relationship between the variance and the cocktail and scaling-relation braking effects is established.We believe the method described in this work will make the ETF more effective in mechanistic studies of HEA electrocatalysis. 展开更多
关键词 high-entropy alloy Electrocatalysis Volcano plot Cocktail effect Scaling-relation breaking effect Adsorption energy distribution
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Influence of pre-stretching on quench sensitive effect of high-strength Al-Zn-Mg-Cu-Zr alloy sheet 被引量:9
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作者 HE Ke-zhun LI Qun +2 位作者 LIU Sheng-dan ZHANG Xin-ming ZHOU Ke-chao 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第9期2660-2669,共10页
The influence of pre-stretching on quench sensitive effect of high strength Al-Zn-Mg-Cu-Zr alloy AA 7085 sheet was investigated by tensile testing at room temperature,transmission electron microscopy(TEM)and different... The influence of pre-stretching on quench sensitive effect of high strength Al-Zn-Mg-Cu-Zr alloy AA 7085 sheet was investigated by tensile testing at room temperature,transmission electron microscopy(TEM)and differential scanning calorimetry(DSC).The water-cooled and aged alloy exhibits higher strength than the air-cooled and aged alloy;2.5%pre-stretching of tensile deformation exerts little effect on strength of water-cooled and aged alloy but increases that of air-cooled and aged one,and therefore the yield strength reduction rate due to slow quenching decreases from about 3.8%to about 1.0%,reducing quench sensitive effect.For the air-cooled alloy,pre-stretching increases the sizes ofη'strengthening precipitates but also increases their quantity and the ratio of diameter to thickness,resulting in enhanced strengthening and higher strength after aging.The reason has been discussed based on microstructure examination by TEM and DSC. 展开更多
关键词 high-strength aluminum alloy PRE-STRETCHING tensile properties quench sensitive effect strengthening precipitates
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Reducing oxidative stress and hepatoprotective effect of water extracts from Pu-erh tea on rats with high-fat diet 被引量:10
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作者 Jingjing Su Xueqing Wang +2 位作者 Wenjun Song Xiaoli Bai Changwen Li 《Food Science and Human Wellness》 SCIE 2016年第4期199-206,共8页
Reducing oxidative stress and hepatoprotective effect of Pu-erh tea water extracts on rats fed with high-fat diet were researched for explaining health care of Pu-erh tea.Fifty SD rats were divided into five groups.Th... Reducing oxidative stress and hepatoprotective effect of Pu-erh tea water extracts on rats fed with high-fat diet were researched for explaining health care of Pu-erh tea.Fifty SD rats were divided into five groups.The body weight was measured once a day.The malondialdehyde(MDA)and glucose(Glu)levels and the activities of alanine aminotransferase(ALT),aspartate aminotransferase(AST),nitric oxide synthase(NOS),and pyruvate kinase(PK)in serum were determined.Furthermore,the hepatic glycogen level(HGL)and the activities of hepatic total superoxide dismutase(T-SOD),catalase(CAT),and glutathione peroxidase(GSH-Px)were also measured after continuous administration for 12 weeks.The result demonstrated that Pu-erh extract caused the decreases in body weight,fat index,MDA and NOS levels,and the increases in hepatic T-SOD,CAT and GSH-Px activities,indicating that the extract may be due to inhibiting the increases of body weight and fat index,reducing oxidant stress state and inhibiting lipid peroxidation,thus decreasing the activities of ALT and AST,and protecting the liver in rat.Meanwhile,the extracts could increase the production of hepatic glycogen and the activity of PK,and reduce glucose level,protecting the liver from the diseases associated with type II diabetes. 展开更多
关键词 Pu-erh tea extracts Oxidative stress Hepatoprotective effect
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