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Effect of process parameters on sheath forming of continuous extrusion sheathing of aluminum 被引量:3
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作者 赵颖 宋宝韫 +3 位作者 运新兵 裴久杨 贾春博 阎志勇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第12期3073-3080,共8页
The effect of flow passage length in the die cavity and extrusion wheel velocity on the shape of aluminum sheath during the continuous extrusion sheathing process was analyzed by using finite element methods based on ... The effect of flow passage length in the die cavity and extrusion wheel velocity on the shape of aluminum sheath during the continuous extrusion sheathing process was analyzed by using finite element methods based on software DEFORM 3D and experimentally validated. The results show that by increasing the flow passage length, the velocity of metal at the cross-section of sheath tends toward uniformity, the values of the bending angles of sheath gradually approach the ideal value of zero and the cross-section exhibits a better shape. The extrusion wheel velocity has negligible effects on the bending shape and cross-section of the sheath product when a long flow passage is used. 展开更多
关键词 continuous extrusion sheathing aluminum sheath sheath forming die design extrusion wheel velocity finite element
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Double⁃Shear Experiments of Cold⁃Formed Steel Stud⁃to⁃Sheathing Connections at Elevated Temperatures
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作者 Kun Liu Wei Chen +3 位作者 Jihong Ye Yuze Yang Jian Jiang Yafei Qin 《Journal of Harbin Institute of Technology(New Series)》 CAS 2021年第6期44-62,共19页
The behavior of cold⁃formed steel(CFS)stud⁃to⁃sheathing connections at elevated temperatures is an important parameter for the fire resistance design and modeling of mid⁃rise CFS structures.In this paper,three kinds o... The behavior of cold⁃formed steel(CFS)stud⁃to⁃sheathing connections at elevated temperatures is an important parameter for the fire resistance design and modeling of mid⁃rise CFS structures.In this paper,three kinds of sheathings,namely,medium⁃and low⁃density calcium⁃silicate boards and oriented strand board,were selected for double⁃shear experiments on the mechanical properties of 253 screw connections at ambient and elevated temperatures.The effects of the shear direction,screw edge distance and the number of screws on the behavior of the connections were studied.The results showed that the shear direction and the screw edge distance more significantly influenced the peak deformation,while their impacts on the peak load varied with the type of sheathings.Compared with the single⁃screw connections,the peak loads of the specimens with double⁃screw connections obviously increased but did not double.Finally,a simplified load⁃displacement curve model of stud⁃to⁃sheathing connections at elevated temperature was generated first by establishing the prediction formula for characteristic parameters,such as the peak load,the peak deformation and the elastic stiffness,and then by considering whether the curves corresponded to stiffness increase phenomena.The present investigation provides basic data for future studies on the numerical modeling of CFS structures under fire conditions. 展开更多
关键词 cold⁃formed steel structures stud⁃to⁃sheathing screw connections double⁃shear experiments elevated temperature load⁃displacement model
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Amphipathic Phenylalanine-Induced Nucleophilic-Hydrophobic Interface Toward Highly Reversible Zn Anode 被引量:1
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作者 Anbin Zhou Huirong Wang +9 位作者 Fengling Zhang Xin Hu Zhihang Song Yi Chen Yongxin Huang Yanhua Cui Yixiu Cui Li Li Feng Wu Renjie Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期95-109,共15页
Aqueous Zn^(2+)-ion batteries(AZIBs),recognized for their high security,reliability,and cost efficiency,have garnered considerable attention.However,the prevalent issues of dendrite growth and parasitic reactions at t... Aqueous Zn^(2+)-ion batteries(AZIBs),recognized for their high security,reliability,and cost efficiency,have garnered considerable attention.However,the prevalent issues of dendrite growth and parasitic reactions at the Zn electrode interface significantly impede their practical application.In this study,we introduced a ubiquitous biomolecule of phenylalanine(Phe)into the electrolyte as a multifunctional additive to improve the reversibility of the Zn anode.Leveraging its exceptional nucleophilic characteristics,Phe molecules tend to coordinate with Zn^(2+)ions for optimizing the solvation environment.Simultaneously,the distinctive lipophilicity of aromatic amino acids empowers Phe with a higher adsorption energy,enabling the construction of a multifunctional protective interphase.The hydrophobic benzene ring ligands act as cleaners for repelling H_(2)O molecules,while the hydrophilic hydroxyl and carboxyl groups attract Zn^(2+)ions for homogenizing Zn^(2+)flux.Moreover,the preferential reduction of Phe molecules prior to H_(2)O facilitates the in situ formation of an organic-inorganic hybrid solid electrolyte interphase,enhancing the interfacial stability of the Zn anode.Consequently,Zn||Zn cells display improved reversibility,achieving an extended cycle life of 5250 h.Additionally,Zn||LMO full cells exhibit enhanced cyclability of retaining 77.3%capacity after 300 cycles,demonstrating substantial potential in advancing the commercialization of AZIBs. 展开更多
关键词 Zn anode PHENYLALANINE Adsorption energy Solvation sheath
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Intelligent monitoring and health management technologies for metal-roof sheathing 被引量:1
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作者 YANG LiMan FU ChenYao +1 位作者 SHI Yan SHEN DongKai 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2019年第9期1655-1656,共2页
Metal-roof sheathings, generally made of cold-bending alloy-steel with insulation, sound-absorbing insulation and waterproof materials, are widely employed in large-span public buildings and industrial buildings such ... Metal-roof sheathings, generally made of cold-bending alloy-steel with insulation, sound-absorbing insulation and waterproof materials, are widely employed in large-span public buildings and industrial buildings such as sports stadiums, airport terminals, exhibition centers, large workshops and warehouses due to their excellent structural performance, unique appearance and installation convenience. 展开更多
关键词 sheathings INSULATION CONVENIENCE
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Characteristics of the electromagnetic wave propagation in magnetized plasma sheath and practical method for blackout mitigation
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作者 吴翔 张珈珲 +1 位作者 董果香 石磊 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期489-499,共11页
“Magnetic window”is considered as an effective method to solve the communication blackout issue.COMSOL software package based on the finite element method is utilized to simulate the propagation of right-handed circ... “Magnetic window”is considered as an effective method to solve the communication blackout issue.COMSOL software package based on the finite element method is utilized to simulate the propagation of right-handed circularly polarized wave in the magnetized plasma sheath.We assume a double Gaussian model of electron density and an exponential attenuation model of magnetic field.The propagation characteristics of right-handed circularly polarized wave are analyzed by the observation of the reflected,transmitted and loss coefficient.The numerical results show that the propagation of right-handed circularly polarized wave in the magnetized plasma sheath varies for different incident angles,collision frequencies,non-uniform magnetic fields and non-uniform plasma densities.We notice that reducing the wave frequency can meet the propagation conditions of whistle mode in the weak magnetized plasma sheath.And the transmittance of whistle mode is less affected by the variation of the electron density and the collision frequency.It can be used as a communication window. 展开更多
关键词 magnetized plasma sheath communication blackout finite element incident angle whistler wave
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Multi-aspect analysis of ureteral access sheath usage in retrograde intrarenal surgery: A RIRSearch group study
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作者 Oktay Özman Hacı M.Akgül +5 位作者 Cem Başataç Önder Çınar Eyüp B.Sancak Cenk M.Yazıcı Bülent Önal Haluk Akpınar 《Asian Journal of Urology》 CSCD 2024年第1期80-85,共6页
Objective:To evaluate the effect of ureteral access sheath(UAS)use and calibration change on stone-free rate and complications of retrograde intrarenal surgery(RIRS).Methods:Data from 568 patients undergoing RIRS for ... Objective:To evaluate the effect of ureteral access sheath(UAS)use and calibration change on stone-free rate and complications of retrograde intrarenal surgery(RIRS).Methods:Data from 568 patients undergoing RIRS for kidney or upper ureteral stones were retrospectively included.Firstly,patients were compared after 1:1 propensity score matching,according to UAS usage during RIRS(UAS used[+]87 and UAS non-used[−]87 patients).Then all UAS+patients(n=481)were subdivided according to UAS calibration:9.5-11.5 Fr,10-12 Fr,11-13 Fr,and 13-15 Fr.Primary outcomes of the study were the success and complications of RIRS.Results:Stone-free rate of UAS+patients(86.2%)was significantly higher than UAS−patients(70.1%)after propensity score matching(p=0.01).Stone-free rate increased with higher caliber UAS(9.5-11.5 Fr:66.7%;10-12 Fr:87.0%;11-13 Fr:90.6%;13-15 Fr:100%;p<0.001).Postoperative complications of UAS+patients(11.5%)were significantly lower than UAS−patients(27.6%)(p=0.01).Complications(8.7%)with 9.5-11.5 Fr UAS was lower than thicker UAS(17.2%)but was not statistically significant(p=0.09).UAS usage was an independent factor predicting stone-free status or peri-and post-operative complications(odds ratio[OR]3.654,95%confidence interval[CI]1.314-10.162;OR 4.443,95%CI 1.350-14.552;OR 4.107,95%CI 1.366-12.344,respectively).Conclusion:Use of UAS in RIRS may increase stone-free rates,which also increase with higher caliber UAS.UAS usage may reduce complications;however,complications seemingly increase with higher UAS calibration. 展开更多
关键词 STONE Retrograde intrarenal surgery Ureteral access sheath UROLITHIASIS Kidney
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Reversible aqueous aluminum metal batteries enabled by a water-in-salt electrolyte
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作者 Wenjing Tang Lijun Deng +3 位作者 Longyuan Guo Shoubin Zhou Qinhai Jiang Jiayan Luo 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第7期1183-1191,共9页
Aluminum(Al),the most abundant metallic element on the earth crust,has been reckoned as a promising battery material for its the highest theoretical volume capacity(8046 mAh cm^(-3)).Being rechargeable in ionic liquid... Aluminum(Al),the most abundant metallic element on the earth crust,has been reckoned as a promising battery material for its the highest theoretical volume capacity(8046 mAh cm^(-3)).Being rechargeable in ionic liquid electrolytes,however,the Al anode and battery case suffer from corrosion.On the other hand,Al is irreversible in aqueous electrolyte with severe hydrogen evolution reaction.Here,we demonstrate a water-in-salt aluminum ion electrolyte(WISE)based on Al and lithium salts to tackle the above challenges.In the WISE system,water molecules can be confined within the Li^(+)solvation structures.This diminished Al^(3+)-H_(2)O interaction essentially eliminates the hydrolysis effect,effectively protecting Al anode from corrosion.Therefore,long-term Al plating/stripping can be realized.Furthermore,two types of high-performance full batteries have been demonstrated using copper hexacyanoferrate(CuHCF,a Prussian Blue Analogues)and LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM)as cathodes.The reversibility of Al anode laid the foundation for low cost rechargeable batteries suffering for large-scale energy storage.Broader context:Al batteries are expected to become a safe and sustainable alternative to lithium batteries.For decades,chase for a feasible Al secondary battery has not been successful.The key challenge is to find suitable cathode and electrolyte materials,together with which Al anode battery can function reversibly.Currently,fatal drawbacks have impeded the practical application of Al metal batteries(AMBs),such as sustained corrosion of Al anode and battery case in ionic liquid electrolytes,irreversibility issues as well as severe hydrogen evolution reaction during cycling in aqueous electrolyte.Therefore,electrolyte and their electrochemical kinetics play a vital role in the performance and environmental operating limitations of high-energy Al metal batteries.In this work,we demonstrate a nearly neutral Al ion water-in-salt electrolyte(WISE)to tackle the above challenges.The WISE shows excellent stability in the open atmosphere.The distinct solvation-sheath structure of Al^(3+)in the WISE system would protect Al metal anodes from corrosion and eliminate hydrogen evolution reaction effectively,further promoting the reversibility of Al metal anodes with dendrite-free morphology.Moreover,such a WISE exhibits superior compatibility with LiNi_(0.3)Co_(0.3)Mn_(0.3)O_(2)(NCM)and copper hexacyanoferrate(CuHCF)cathodes and long-term stabilities with high coulombic efficiency(CE)can be attained for full batteries with the WISE.The approach in this study can furnish an opportunity to develop reversible AMBs and lay the foundation for other potential multivalent-metalbased secondary batteries suffering from interface passivation and poor reversibility,which suggest the promise of multivalent metal batteries and their applications in large-scale energy storage. 展开更多
关键词 Water-in-salt electrolyte Rechargeable aluminum anode Solvation sheath Hybrid battery Abundance
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Effect of a cervical collar on optic nerve sheath diameter in trauma patients
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作者 Mümin Murat Yazici Ozcan Yavasi 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第2期126-130,共5页
BACKGROUND:As advocated in advanced trauma life support and prehospital trauma life support protocols,cervical immobilization is applied until cervical spine injury is excluded.This study aimed to show the difference ... BACKGROUND:As advocated in advanced trauma life support and prehospital trauma life support protocols,cervical immobilization is applied until cervical spine injury is excluded.This study aimed to show the difference in optic nerve sheath diameter(ONSD)between patients with and without a cervical collar using computed tomography(CT).METHODS:This was a single-center,retrospective study examining trauma patients who presented to the emergency department between January 1,2021,and December 31,2021.The ONSD on brain CT of the trauma patients was measured and analyzed to determine whether there was a difference between the ONSD with and without the cervical collar.RESULTS:The study population consisted of 169 patients.On CT imaging of patients with(n=66)and without(n=103)cervical collars,the mean ONSD in the axial plane were 5.43±0.50 mm and 5.04±0.46 mm respectively for the right eye and 5.50±0.52 mm and 5.11±0.46 mm respectively for the left eye.The results revealed an association between the presence of a cervical collar and the mean ONSD,which was statistically significant(P<0.001)for both the right and left eyes.CONCLUSION:A cervical collar may be associated with increased ONSD.The effect of this increase in the ONSD on clinical outcomes needs to be investigated,and the actual need for cervical collar in the emergency department should be evaluated on a case-by-case basis. 展开更多
关键词 Optic nerve sheath diameter Computed tomography TRAUMA Emergency medicine
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Heterogeneity of mature oligodendrocytes in the central nervous system
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作者 Chao Weng Adam M.R.Groh +4 位作者 Moein Yaqubi Qiao-Ling Cui Jo Anne Stratton G.R.Wayne Moore Jack P.Antel 《Neural Regeneration Research》 SCIE CAS 2025年第5期1336-1349,共14页
Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous system.Recent evidence has challenged the classical view of the functio... Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous system.Recent evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to axons.Despite the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is lacking.We delve into early 20th-century studies by Robertson and Río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature oligodendrocytes.Indeed,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination preferences.Furthermore,modern molecular investigations,employing techniques such as single cell/nucleus RNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system region.Age and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric disorders.Nevertheless,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined investigations.Future studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte heterogeneity.Such research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,hold promise for the development of therapeutic interventions targeting varied central nervous system pathology. 展开更多
关键词 aging central nervous system diseases electron microscopy HETEROGENEITY immunohistochemistry myelin sheath natural history NEUROGLIA OLIGODENDROGLIA single-cell gene expression analysis
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Effect of ion stress on properties of magnetized plasma sheath
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作者 陈龙 崔作君 +4 位作者 高维富 段萍 阚子晨 檀聪琦 陈俊宇 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期1-12,共12页
In the plasma sheath, there is a significant gradient in ion velocity, resulting in strong stress on ions treated as a fluid. This aspect has often been neglected in previous sheath studies. This study is based on the... In the plasma sheath, there is a significant gradient in ion velocity, resulting in strong stress on ions treated as a fluid. This aspect has often been neglected in previous sheath studies. This study is based on the Braginskii plasma transport theory and establishes a 1D3V sheath fluid model that takes into account the ion stress effect. Under the assumption that ions undergo both electric and diamagnetic drift in the presheath region, self-consistent boundary conditions,including the ion Bohm velocity, are derived based on the property of the Sagdeev pseudopotential.Furthermore, assuming that the electron velocity at the wall follows a truncated Maxwell distribution, the wall floating potential is calculated, leading to a more accurate sheath thickness estimation. The results show that ion stress significantly reduces the sheath thickness, enhances ion Bohm velocity, wall floating potential, and ion flux at the wall. It hinders the acceleration of ions within the sheath, leading to notable alterations in the particle density profiles within the sheath. Further research indicates that in ion stress, bulk viscous stress has the greatest impact on sheath properties. 展开更多
关键词 magnetized plasma sheath ion stress Bohm criterion
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The multi-peak point phenomenon of broadband microwave reflection caused by inhomogeneous plasma
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作者 杨敏 齐凯旋 +5 位作者 杨玖文 贾飒 刘浩岩 陈燕扬 李瑾 李小平 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第7期1-11,共11页
During spacecraft re-entry,the challenge of measuring plasma sheath parameters directly contributes to difficulties in addressing communication blackout.In this work,we have discovered a phenomenon of multiple peaks i... During spacecraft re-entry,the challenge of measuring plasma sheath parameters directly contributes to difficulties in addressing communication blackout.In this work,we have discovered a phenomenon of multiple peaks in reflection data caused by the inhomogeneous plasma.Simulation results show that the multi-peak points fade away as the characteristic frequency is approached,resembling a series of gradually decreasing peaks.The positions and quantities of these points are positively correlated with electron density,yet they show no relation to collision frequency.This phenomenon is of significant reference value for future studies on the spatial distribution of plasmas,particularly for using microwave reflection signals in diagnosing the plasma sheath. 展开更多
关键词 plasma sheath microwave reflection inhomogeneous plasma
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Analyses of nonequilibrium transport in atmospheric-pressure direct-current argon discharge under different modes
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作者 Ziming ZHANG Chuan FANG +2 位作者 Yaoting WANG Lanyue LUO Heping LI 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第11期107-126,共20页
The key plasma parameters under different discharge modes, such as heavy-particle and electron temperatures, electron number density, and nonequilibrium volume of plasmas, play important roles in various applications ... The key plasma parameters under different discharge modes, such as heavy-particle and electron temperatures, electron number density, and nonequilibrium volume of plasmas, play important roles in various applications of gas discharge plasmas. In this study, a self-consistent two-dimensional nonequilibrium fluid model coupled with an external circuit model is established to reveal the mechanisms related to the discharge modes, including the normal glow, abnormal glow,arc, and glow-to-arc transition modes, with an atmospheric-pressure direct-current(DC) argon discharge as a model plasma system. The modeling results show that, under different discharge modes, the most significant difference between the preceding four discharge modes lies in the current and energy transfer processes on the cathode side. On one hand, the current to the cathode surface is mainly delivered by the ions coming from the plasma column under the glow discharge mode due to the low temperature of the solid cathode, whereas the thermionic and secondary electrons emitted from the hot cathode surface play a very important role under the arc mode with a higher cathode surface temperature and higher ion flux toward the cathode. On the other hand, the energy transfer channel on the cathode side changes from mainly heating the solid cathode under the glow mode to simultaneously heating both the solid cathode and plasma column under the arc mode with an increase in the discharge current. Consequently, the power density in the cathode sheath(P_c) was used as a key parameter for judging different discharge modes, and the range of(0.28–1.2) × 10^(12) W m^(-3) was determined as a critical window of P_c corresponding to the glow-to-arc-mode transition for the atmospheric-pressure DC argon discharge, which was also verified by comparison with the experimental results in this study and the data in the previous literature. 展开更多
关键词 atmospheric-pressure plasma direct-current gas discharge discharge mode mode transition power density in cathode sheath
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Fluid-chemical modeling of the near-cathode sheath formation process in a high current broken in DC air circuit breaker
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作者 彭世东 李静 +3 位作者 段薇 曹云东 刘树鑫 黄浩 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期523-538,共16页
When the contacts of a medium-voltage DC air circuit breaker(DCCB) are separated, the energy distribution of the arc is determined by the formation process of the near-electrode sheath. Therefore, the voltage drop thr... When the contacts of a medium-voltage DC air circuit breaker(DCCB) are separated, the energy distribution of the arc is determined by the formation process of the near-electrode sheath. Therefore, the voltage drop through the near-electrode sheath is an important means to build up the arc voltage, which directly determines the current-limiting performance of the DCCB. A numerical model to describe the near-electrode sheath formation process can provide insight into the physical mechanism of the arc formation, and thus provide a method for arc energy regulation. In this work, we establish a two-dimensional axisymmetric time-varying model of a medium-voltage DCCB arc when interrupted by high current based on a fluid-chemical model involving 16 kinds of species and 46 collision reactions. The transient distributions of electron number density, positive and negative ion number density, net space charge density, axial electric field, axial potential between electrodes, and near-cathode sheath are obtained from the numerical model. The computational results show that the electron density in the arc column increases, then decreases, and then stabilizes during the near-cathode sheath formation process, and the arc column's diameter gradually becomes wider. The 11.14 V–12.33 V drops along the17 μm space charge layer away from the cathode(65.5 k V/m–72.5 k V/m) when the current varies from 20 k A–80 k A.The homogeneous external magnetic field has little effect on the distribution of particles in the near-cathode sheath core,but the electron number density at the near-cathode sheath periphery can increase as the magnetic field increases and the homogeneous external magnetic field will lead to arc diffusion. The validity of the numerical model can be proven by comparison with the experiment. 展开更多
关键词 near-cathode sheath atmospheric pressure air arc fluid-chemical model high current DC air circuit breaker(DCCB)
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Dengue hemorrhagic fever with rectus sheath hematoma:A case report
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作者 Boudhayan Bhattacharjee Hardik Patel +4 位作者 Rucha Karad Vasireddy Teja Agnibho Mondal Soumendra Nath Haldar Bibhuti Saha 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第3期136-138,共3页
Rationale:Acute pain is a medical emergency that requires prompt abdominal evaluation and management.Dengue,a mosquito-borne arboviral infection,can lead to complications such as acute abdominal pain.Patient concerns:... Rationale:Acute pain is a medical emergency that requires prompt abdominal evaluation and management.Dengue,a mosquito-borne arboviral infection,can lead to complications such as acute abdominal pain.Patient concerns:A 72-year-old hypertensive female presented with high-grade intermittent fever with chills and rigors for four days.She was diagnosed with dengue fever(NS1Ag-reactive)the day before admission.A contrast-enhanced computed tomography of the abdomen showed a hematoma along the rectus sheath which was managed conservatively as per surgical opinion.Diagnosis:Dengue hemorrhagic fever with rectus sheath hematoma.Interventions:Blood transfusion and fluid therapy.Outcomes:Ten days after discharge,the patient reproted no pain in the right iliac fossa and the size of the hematoma was significantly reduced.Lessons:Although it is rarely seen as a cause of acute abdomen,complaints of adnominal pain should never be ignored in critical or convalescent phase of dengue fever.Radiological investigations should be promptly conducted as hematoma is often difficult to be diagnosed clinically.Delay in diagnosis of rectus sheath hematoma can be fatal. 展开更多
关键词 Dengue fever Rectus sheath hematoma Surgical emergency Acute appendicitis
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Electron characteristics and dynamics in sub-millimeter pulsed atmospheric dielectric barrier discharge
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作者 方骏林 张亚容 +4 位作者 卢陈梓 顾莉莉 徐少锋 郭颖 石建军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期496-502,共7页
The discharge characteristics and mechanism of sub-millimeter pulsed dielectric barrier discharge in atmosphericpressure helium are investigated experimentally and theoretically, demonstrating that when the discharge ... The discharge characteristics and mechanism of sub-millimeter pulsed dielectric barrier discharge in atmosphericpressure helium are investigated experimentally and theoretically, demonstrating that when the discharge gap distance is reduced from 1.00 mm to 0.20 mm, the discharge ignition time is reduced to approximately 40 ns and discharge intensity is enhanced in terms of the discharge optical emission intensity and density of the plasma species,(energetic electrons with energy above 8.40 e V). The simulated results show that as the discharge gap distance is further reduced to 0.10 mm,the number of energetic electrons decreases, which is attributable to the contraction of plasma bulk regime and reduction of electron density in the discharge bulk. Conversely, the proportion of energetic electrons to the total electrons in the discharge monotonically increases as the discharge gap distance is reduced from 1.00 mm to 0.10 mm. It is proposed that a gap distance of 0.12 mm is optimal to achieve a high concentration and proportion of energetic electrons in sub-millimeter pulsed atmosphere dielectric barrier discharge. 展开更多
关键词 sub-millimeter pulsed discharge plasma simulation electron dynamics and sheath
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Epithelioid malignant peripheral nerve sheath tumor of the bladder and concomitant urothelial carcinoma: A case report
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作者 Sami Berk Ozden Muhammed Fatih Simsekoglu +2 位作者 Ipek Sertbudak Cetin Demirdag Iclal Gurses 《World Journal of Clinical Cases》 SCIE 2024年第3期551-559,共9页
BACKGROUND Epithelioid malignant peripheral nerve sheath tumor(EMPNST)of the bladder is a rare entity with devastating features.These tumors are thought to originate from malignant transformation of pre-existing schwa... BACKGROUND Epithelioid malignant peripheral nerve sheath tumor(EMPNST)of the bladder is a rare entity with devastating features.These tumors are thought to originate from malignant transformation of pre-existing schwannomas of pelvic autonomic nerve plexuses,and unlike the conventional malignant peripheral nerve sheath tumor(MPNST),are not associated with neurofibromatosis.The tumor has dis-tinctive morphological,immunohistochemical and molecular features.Addi-tionally,it tends to be more aggressive and have a higher mortality.This is the first case that presents with a synchronous urothelial carcinoma of the bladder and the epithelioid variant of MPNST in the literature.It’s also the second re-ported case of EMPNST originating from the bladder wall.CASE SUMMARY In this case report,we present the detailed clinical course of a 71-year-old patient with EMPNST of the bladder alongside a literature review.CONCLUSION During the management of EMPNST cases,offering aggressive treatment moda-lities to the patient,such as radical cystectomy,is appropriate for the best chance to contain the disease,regardless of the tumor stage and the extent of local disease at initial diagnosis. 展开更多
关键词 EPITHELIOID Peripheral nerve sheath tumor BLADDER Case report UROTHELIAL CYSTOPROSTATECTOMY
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Symmetry of upper eyelid after unilateral blepharoptosis repair with minimally invasive conjoint fascial sheath suspension technique
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作者 Yianzhu Liu Wenli Chen Xia Chen 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第1期53-60,共8页
AIM:To investigate the symmetry of upper eyelid in patients with unilateral mild and moderate blepharoptosis who underwent unilateral minimally invasive combined fascia sheath(CFS)suspension.METHODS:A retrospective st... AIM:To investigate the symmetry of upper eyelid in patients with unilateral mild and moderate blepharoptosis who underwent unilateral minimally invasive combined fascia sheath(CFS)suspension.METHODS:A retrospective study of patients who underwent unilateral minimally invasive CFS suspension surgery between January 2018 and December 2021.Inclusion criteria included unilateral mild and moderate ptosis,good levator muscle function(>9 mm)and follow-up of at least 6mo.Pre-and post-operative symmetry was graded subjectively for marginal reflex distance 1(MRD1),tarsal platform show(TPS)and eyebrow fat span(BFS).A t-test was used to evaluate MRD1,TPS and BFS asymmetry by calculating delta values.The Bézier curve tool of the Image J software was used to extract the upper eyelid contours,where the symmetry was measured by the percentage of overlapping curvatures(POC).RESULTS:Totally 105 patients(105 eyelids)were included(mild group,n=84;moderate group,n=21).Postoperatively,all patients increased MRD1 and decreased TPS in the ptotic eye while maintaining unchanged BFS.The asymmetric delta value for MRD1 was measured to be 1.48±0.86 preoperatively,and it decreased to 0.58±0.67 postoperatively in all cases(P=0.0004).In patients with mild ptosis,the asymmetry value of TPS fell significantly from 1.15±0.62 to 0.68±0.38(P=0.0187).The symmetry of the upper eyelid contour increased in all subgroups of patients,with a POC of 59.39%±13.45%preoperatively and POC of 78.29%±13.80%postoperatively.CONCLUSION:Minimally invasive CFS suspension is proved to be an effective means of improving the symmetry of unilateral ptosis in terms of MRD1(all subgroups),POC(all subgroups)and TPS(only mild group),whereas BFS is unaffected. 展开更多
关键词 SYMMETRY unilateral blepharoptosis minimally invasive combined fascia sheath suspension
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Rectus sheath hematoma combined with COVID-19:A case report
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作者 Wei Wang Jie Duan 《World Journal of Clinical Cases》 SCIE 2024年第20期4325-4330,共6页
BACKGROUND Rectus sheath hematoma(RSH)is uncommon,and because people have limited knowledge about it,it is difficult to recognize the symptoms in time,often delaying optimal treatment.CASE SUMMARY Herein,we report a c... BACKGROUND Rectus sheath hematoma(RSH)is uncommon,and because people have limited knowledge about it,it is difficult to recognize the symptoms in time,often delaying optimal treatment.CASE SUMMARY Herein,we report a case of a 77-year-old female with RSH.The patient was treated at our hospital for coronavirus disease 2019.Anticoagulant treatment was administered during this period because of thrombosis.On the 8th d of treatment,the patient complained of abdominal pain.Ultrasonography revealed a solid cystic mass in the pelvic cavity.An emergency laparotomy was performed,and a huge hematoma was found in the deep layer of the rectus abdominis muscle.We used anticoagulants with caution based on the patient’s condition.CONCLUSION Optimal management of patients with RSH s depends on timely diagnosis and when to reintroduce anticoagulants. 展开更多
关键词 Clinical manifestations COVID-19 DIAGNOSIS Rectus sheath hematoma TREATMENT Case report
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Bone marrow mesenchymal stem cells in treatment of peripheral nerve injury
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作者 Xiong-Fei Zou Bao-Zhong Zhang +1 位作者 Wen-Wei Qian Florence Mei Cheng 《World Journal of Stem Cells》 SCIE 2024年第8期799-810,共12页
Peripheral nerve injury(PNI)is a common neurological disorder and complete functional recovery is difficult to achieve.In recent years,bone marrow mesenchymal stem cells(BMSCs)have emerged as ideal seed cells for PNI ... Peripheral nerve injury(PNI)is a common neurological disorder and complete functional recovery is difficult to achieve.In recent years,bone marrow mesenchymal stem cells(BMSCs)have emerged as ideal seed cells for PNI treatment due to their strong differentiation potential and autologous trans-plantation ability.This review aims to summarize the molecular mechanisms by which BMSCs mediate nerve repair in PNI.The key mechanisms discussed include the differentiation of BMSCs into multiple types of nerve cells to promote repair of nerve injury.BMSCs also create a microenvironment suitable for neuronal survival and regeneration through the secretion of neurotrophic factors,extracellular matrix molecules,and adhesion molecules.Additionally,BMSCs release pro-angiogenic factors to promote the formation of new blood vessels.They modulate cytokine expression and regulate macrophage polarization,leading to immunomodulation.Furthermore,BMSCs synthesize and release proteins related to myelin sheath formation and axonal regeneration,thereby promoting neuronal repair and regeneration.Moreover,this review explores methods of applying BMSCs in PNI treatment,including direct cell trans-plantation into the injured neural tissue,implantation of BMSCs into nerve conduits providing support,and the application of genetically modified BMSCs,among others.These findings confirm the potential of BMSCs in treating PNI.However,with the development of this field,it is crucial to address issues related to BMSC therapy,including establishing standards for extracting,identifying,and cultivating BMSCs,as well as selecting application methods for BMSCs in PNI such as direct transplantation,tissue engineering,and genetic engineering.Addressing these issues will help translate current preclinical research results into clinical practice,providing new and effective treatment strategies for patients with PNI. 展开更多
关键词 Bone marrow mesenchymal stem cells Peripheral nerve injury Schwann cells Myelin sheath Tissue engineering
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Relationship between intracranial pressure and neurocognitive function among older adults after radical resection of rectal cancer
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作者 Bo Song Li-Ping Li +2 位作者 Xiao-Lin Wang Yong Guo Jun Li 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第10期3261-3268,共8页
BACKGROUND Older patients are prone to postoperative cognitive decline after laparoscopic rectal cancer surgery,which may be associated with increased intraoperative intracranial pressure(ICP).This study investigated ... BACKGROUND Older patients are prone to postoperative cognitive decline after laparoscopic rectal cancer surgery,which may be associated with increased intraoperative intracranial pressure(ICP).This study investigated the correlation between intra-operative ICP changes,as indicated by measurements of the optic nerve sheath diameter(ONSD)using ultrasonography,and subsequent cognitive function to provide better patient care.AIM To evaluate changes in ICP and associated postoperative neurocognition in older adults after laparoscopic radical resection for rectal cancer.METHODS We included 140 patients who visited the Mianyang Central Hospital for malig-nant rectal tumors,measured their ONSDs before surgery and 30 and 60 minutes after the Trendelenburg position during surgery,and evaluated the patients’cog-nitive function 1 day before surgery and 1,4,and 7 days after surgery.The Mini-Mental State Examination(MMSE)and confusion assessment method(CAM)scores of the patients with different ONSDs were compared at different times after surgery.RESULTS In patients with an ONSD greater than 5.00 mm(group A1),the MMSE scores at 1 day and 4 days after surgery were significantly lower than those of patients with an ONSD less than or equal to 4.00 mm(group A2)(P<0.05).The CAM scores of group A1 were significantly higher than those of group A2(P<0.05).The MMSE scores of group A1 on days 1 and 4 after surgery were significantly lower than those 1 day before and 7 days after surgery(P<0.05),while the CAM scores 1 day and 4 days after surgery were significantly higher than those 1 day before and 7 days after surgery.CONCLUSION Decline in cognitive function among older adults after the procedure may be related to intracranial hypertension during surgery. 展开更多
关键词 ULTRASOUND Optic nerve sheath diameter Intracranial pressure Cognitive function Radical resection Rectal cancer
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