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Microstructure and damping properties of LPSO phase dominant Mg-Ni-Y and Mg-Zn-Ni-Y alloys 被引量:1
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作者 Ruopeng Lu Kai Jiao +3 位作者 Nanting Li Hua Hou Jingfeng Wang Yuhong Zhao 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期1131-1153,共23页
This work studied the microstructure,mechanical properties and damping properties of Mg_(95.34)Ni_(2)Y_(2.66) and Mg_(95.34)Zn_(1)Ni_(1)Y_(2.66)alloys systematically.The difference in the evolution of the long-period ... This work studied the microstructure,mechanical properties and damping properties of Mg_(95.34)Ni_(2)Y_(2.66) and Mg_(95.34)Zn_(1)Ni_(1)Y_(2.66)alloys systematically.The difference in the evolution of the long-period stacked ordered(LPSO)phase in the two alloys during heat treatment was the focus.The morphology of the as-cast Mg_(95.34)Ni_(2)Y_(2.66)presented a disordered network.After heat treatment at 773 K for 2 hours,the eutectic phase was integrated into the matrix,and the LPSO phase maintained the 18R structure.As Zn partially replaced Ni,the crystal grains became rounded in the cast alloy,and lamellar LPSO phases and more solid solution atoms were contained in the matrix after heat treatment of the Mg_(95.34)Zn_(1)Ni_(1)Y_(2.66)alloy.Both Zn and the heat treatment had a significant effect on damping.Obvious dislocation internal friction peaks and grain boundary internal friction peaks were found after temperature-dependent damping of the Mg_(95.34)Ni_(2)Y_(2.66)and Mg_(95.34)Zn_(1)Ni_(1)Y_(2.66)alloys.After heat treatment,the dislocation peak was significantly increased,especially in the alloy Mg_(95.34)Ni_(2)Y_(2).66.The annealed Mg_(95.34)Ni_(2)Y_(2.66)alloy with a rod-shaped LPSO phase exhibited a good damping performance of 0.14 atε=10^(−3),which was due to the difference between the second phase and solid solution atom content.These factors also affected the dynamic modulus of the alloy.The results of this study will help in further development of high-damping magnesium alloys. 展开更多
关键词 Mg-Ni-Y alloys Mg-Zn-Ni-Y alloys LPSO phase Heat treatment MICROSTRUCTURE damping properties.
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Abnormal expression and significance of circ-CBLB/miR-486-5p in patients with rheumatoid arthritis of spleen deficiency and dampness excess type
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作者 LI Shu WAN Lei +5 位作者 LIU Jian HUANG Chuan-bing CHEN Ying-ying LI Fang-ze HU Sai-sai CHENG Jing 《Journal of Hainan Medical University》 CAS 2023年第17期43-49,共7页
Objective:To explore the abnormal expression and significance of circ-CBLB/miR-486-5p in patients with rheumatoid arthritis of spleen deficiency and dampness excess type.Methods:The 30 healthy individuals included in ... Objective:To explore the abnormal expression and significance of circ-CBLB/miR-486-5p in patients with rheumatoid arthritis of spleen deficiency and dampness excess type.Methods:The 30 healthy individuals included in the method were from the Physical Examination Center of Anhui Provincial Hospital of Traditional Chinese Medicine,and the 60 rheumatoid arthritis patients included were from the First Affiliated Hospital of Anhui University of Traditional Chinese Medicine.The disease activity score of patients with rheumatoid arthritis was evaluated using VAS score and DAS28 score,joint symptoms and spleen deficiency syndrome score were evaluated using graded quantification method,immune inflammation indicators were detected using relevant instruments,inflammatory cytokines were detected using ELISA method,macrophage markers were detected using FCM method,and pathway gene expression was detected using RT-qPCR;Evaluate the predictive effect of circ-CBLB and miR-486-5p on disease activity in rheumatoid arthritis using ROC curves.Results:(1)miR-486-5p,CD14^(+)CD86^(+),ESR,CRP,RF,Anti CCP Ab,IL-6,TNF in patients with rheumatoid arthritis-αThe levels of circ-CBLB,CD14^(+)CD163^(+),IL-4,and IL-10 were significantly higher than those of healthy individuals;(2)The expression level of circ-CBLB in patients with rheumatoid arthritis is positively correlated with CD14^(+)CD163^(+),and negatively correlated with miR-486-5p and CD14^(+)CD86^(+);The expression level of miR-486-5p is negatively correlated with CD14^(+)CD163^(+)and positively correlated with CD14^(+)CD86^(+);There is a negative correlation between CD14^(+)CD86^(+)and CD14^(+)CD163^(+);ESR is negatively correlated with circ-CBLB,and positively correlated with miR-486-5p,CD14^(+)CD86^(+),CRP;CRP is negatively correlated with circ-CBLB,CD14^(+)CD163^(+),and positively correlated with CD14^(+)CD86^(+),ESR;(3)The expression level of circ-CBLB in patients with rheumatoid arthritis is negatively correlated with joint tenderness,morning stiffness,lack of qi and lazy speech,and postprandial abdominal distension score;The expression level of miR-486-5p is positively correlated with the scores of joint tenderness and decreased appetite.(4)The ROC curve shows that in terms of circ-CBLB,ESR,CRP,VAS,and DAS28 AUC are 0.662(P=0.032),0.658(P=0.035),0.516(P=0.830),and 0.791(P=0.000),respectively.In terms of miR-486-5p,ESR,CRP,VAS,and DAS28 AUC were 0.566(P=0.385),0.511(P=0.883),0.592(P=0.223),and 0.727(P=0.003),respectively.Conclusion:The abnormal expression of circ CBLB and miR-486-5p in peripheral blood mononuclear cell of patients with rheumatoid arthritis of spleen deficiency and dampness excess type is related to inflammatory polarization markers,immune inflammation,disease activity,joint symptoms and spleen deficiency syndrome of rheumatoid arthritis,and the low expression of circ CBLB and high expression of miR-486-5p have certain predictive value for disease activity of rheumatoid arthritis. 展开更多
关键词 Rheumatoid arthritis circ-CBLB MiR-486-5p Inflammatory polarization Spleen deficiency and dampness excess syndrome
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Aseismic performances of constrained damping lining structures made of rubber-sand-concrete
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作者 Xiancheng Mei Qian Sheng +4 位作者 Jian Chen Zhen Cui Jianhe Li Chuanqi Li Daniel Dias 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1522-1537,共16页
Flexible damping technology considering aseismic materials and aseismic structures seems be a good solution for engineering structures.In this study,a constrained damping structure for underground tunnel lining,using ... Flexible damping technology considering aseismic materials and aseismic structures seems be a good solution for engineering structures.In this study,a constrained damping structure for underground tunnel lining,using a rubber-sand-concrete(RSC)as the aseismic material,is proposed.The aseismic performances of constrained damping structure were investigated by a series of hammer impact tests.The damping layer thickness and shape effects on the aseismic performance such as effective duration and acceleration amplitude of time-domain analysis,composite loss factor and damping ratio of the transfer function analysis,and total vibration level of octave spectrum analysis were discussed.The hammer impact tests revealed that the relationship between the aseismic performance and damping layer thickness was not linear,and that the hollow damping layer had a better aseismic performance than the flat damping layer one.The aseismic performances of constrained damping structure under different seismicity magnitudes and geological conditions were investigated.The effects of the peak ground acceleration(PGA)and tunnel overburden depth on the aseismic performances such as the maximum principal stress and equivalent plastic strain(PEEQ)were discussed.The numerical results show the constrained damping structure proposed in this paper has a good aseismic performance,with PGA in the range(0.2-1.2)g and tunnel overburden depth in the range of 0-300 m. 展开更多
关键词 Constrained damping structure Aseismic performance Hammer impact tests damping layer Peak ground acceleration Overburden depth
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Prediction of Damping Capacity Demand in Seismic Base Isolators via Machine Learning
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作者 Ayla Ocak Umit Isıkdag +3 位作者 Gebrail Bekdas Sinan Melih Nigdeli Sanghun Kim ZongWoo Geem 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2899-2924,共26页
Base isolators used in buildings provide both a good acceleration reduction and structural vibration control structures.The base isolators may lose their damping capacity over time due to environmental or dynamic effe... Base isolators used in buildings provide both a good acceleration reduction and structural vibration control structures.The base isolators may lose their damping capacity over time due to environmental or dynamic effects.This deterioration of them requires the determination of the maintenance and repair needs and is important for the long-termisolator life.In this study,an artificial intelligence prediction model has been developed to determine the damage and maintenance-repair requirements of isolators as a result of environmental effects and dynamic factors over time.With the developed model,the required damping capacity of the isolator structure was estimated and compared with the previously placed isolator capacity,and the decrease in the damping property was tried to be determined.For this purpose,a data set was created by collecting the behavior of structures with single degrees of freedom(SDOF),different stiffness,damping ratio and natural period isolated from the foundation under far fault earthquakes.The data is divided into 5 different damping classes varying between 10%and 50%.Machine learning model was trained in damping classes with the data on the structure’s response to random seismic vibrations.As a result of the isolator behavior under randomly selected earthquakes,the recorded motion and structural acceleration of the structure against any seismic vibration were examined,and the decrease in the damping capacity was estimated on a class basis.The performance loss of the isolators,which are separated according to their damping properties,has been tried to be determined,and the reductions in the amounts to be taken into account have been determined by class.In the developed prediction model,using various supervised machine learning classification algorithms,the classification algorithm providing the highest precision for the model has been decided.When the results are examined,it has been determined that the damping of the isolator structure with the machine learning method is predicted successfully at a level exceeding 96%,and it is an effective method in deciding whether there is a decrease in the damping capacity. 展开更多
关键词 Vibration control base isolation machine learning damping capacity
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Mechanical and damping performances of TPMS lattice metamaterials fabricated by laser powder bed fusion
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作者 Yan-peng Wei Huai-qian Li +7 位作者 Jing-jing Han Ying-chun Ma Hao-ran Zhou Jing-chang Cheng Jian Shi Zhi-quan Miao Bo Yu Feng Lin 《China Foundry》 SCIE EI CAS CSCD 2024年第4期327-333,共7页
Lattice metamaterials based on three-period minimum surface(TPMS)are an effective means to achieve lightweight and high-strength materials which are widely used in various fields such as aerospace and ships.However,it... Lattice metamaterials based on three-period minimum surface(TPMS)are an effective means to achieve lightweight and high-strength materials which are widely used in various fields such as aerospace and ships.However,its vibration and noise reduction,and damping properties have not been fully studied.Therefore,in this study,the TPMS structures with parameterization were designed by the method of surface migration,and the TPMS structures with high forming quality was manufactured by laser powder bed fusion(LPBF).The mechanical properties and energy absorption characteristics of the beam and TPMS structures were studied and compared by quasi-static compression.The modal shapes of the beam lattice structures and TPMS structures were obtained by the free modal analysis,and the damping properties of two structures were obtained by modal tests.For the two structures after heat treatment with the same porosity of 70%,the yield strength of the beam lattice structure reaches 40.76 MPa,elastic modulus is 20.38 GPa,the energy absorption value is 32.23 MJ·m^(-3),the damping ratio is 0.52%.The yield strength,elastic modulus,energy absorption value,and damping ratio of the TPMS structure are 50.74 MPa,25.37 GPa,47.34 MJ·m^(-3),and 0.99%,respectively.The results show that TPMS structures exhibit more excellent mechanical properties and energy absorption,better damping performance,and obvious advantages in structural load and vibration and noise reduction compared with the beam lattice structures under the same porosity. 展开更多
关键词 lattice metamaterials TPMS energy absorption dampING laser powder bed fusion
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Near resonance vibration isolation on a levered-dual response(LEDAR)Coulomb-damped system by differential preloads/offsets in linear springs
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作者 T.I.TOLUWALOJU C.K.THEIN D.HALIM 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第6期1033-1050,共18页
The levered-dual response(LEDAR)Coulomb-damped system attains near resonant vibration isolation by differential preloads/offsets in linear springs.It takes the advantages of both the preloads/offsets in linear springs... The levered-dual response(LEDAR)Coulomb-damped system attains near resonant vibration isolation by differential preloads/offsets in linear springs.It takes the advantages of both the preloads/offsets in linear springs and the guiderail friction for realizing different levels of vibration isolation.The isolation capacities are investigated on the strategies with both the horizontal and vertical guiderails,with the horizontal rail only,and without guiderails.The compressive preloads generally result in the consumption of most of the initial excitation energy so as to overcome the potential threshold.The isolation onsets at the frequency ratio of 1∓0.095 on the left-hand side(LHS)and the right-hand side(RHS)of the lever are relative to the load plate connector.The observed near resonant isolation thus makes the LEDAR system a candidate for the isolation of the mechanical systems about resonance while opening a path for simultaneous harvesterisolation functions and passive functions at extreme frequencies. 展开更多
关键词 lever ratio Coulomb damping preload tension/compression isolation band/depth offset potential
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Transient Damping of Virtual Synchronous Generator for Enhancing Synchronization Stability during Voltage Dips
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作者 Shitao Sun Yu Lei +4 位作者 Guowen Hao Yi Lu Jindong Liu Zhaoxin Song Jie Zhang 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第2期143-151,共9页
Virtual synchronous generators(VSGs)are widely introduced to the renewable power generation,the variablespeed pumped storage units,and so on,as a promising gridforming solution.It is noted that VSGs can provide virtua... Virtual synchronous generators(VSGs)are widely introduced to the renewable power generation,the variablespeed pumped storage units,and so on,as a promising gridforming solution.It is noted that VSGs can provide virtual inertia for frequency support,but the larger inertia would worsen the synchronization stability,referring to keeping synchronization with the grid during voltage dips.Thus,this paper presents a transient damping method of VSGs for enhancing the synchronization stability during voltage dips.It is revealed that the loss of synchronization(LOS)of VSGs always accompanies with the positive frequency deviation and the damping is the key factor to remove LOS when the equilibrium point exists.In order to enhance synchronization stability during voltage dips,the transient damping is proposed,which is generated by the frequency deviation in active power loop.Additionally,the proposed method can realize seamless switching between normal state and grid fault.Moreover,detailed control design for transient damping gain is given to ensure the synchronization stability under different inertia requirements during voltage dips.Finally,the experimental results are presented to validate the analysis and the effectiveness of the improved transient damping method. 展开更多
关键词 Virtual synchronous generator(VSG) Transient damping Synchronization stability Voltage dips
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Observation on Therapeutic Effects of Electroacupuncture on Polycystic Ovary Syndrome of Kidney Deficiency and Phlegm Dampness Type and Oxidative Stress Level
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作者 周竞 刘晓竹 +2 位作者 汪迪 胡智海 马桂芝 《World Journal of Integrated Traditional and Western Medicine》 2023年第2期14-23,共10页
Objective:To observe the clinical effect of electroacupuncture on improving polycystic ovary syndrome(PCOS)of kidney deficiency and phlegm dampness type and serum oxidative stress level.Methods:There were 68 patients ... Objective:To observe the clinical effect of electroacupuncture on improving polycystic ovary syndrome(PCOS)of kidney deficiency and phlegm dampness type and serum oxidative stress level.Methods:There were 68 patients with polycystic ovary syndrome were randomly divided into observation group(34 cases)and the control group(34 cases),The observation group was treated by electroacupuncture,while the control group was treated by placebo electroacupuncture.Combined with the evaluation of menstrual cycle,menstrual color,quality,quantity and TCM symptom integral index,the difference of curative effect between the two groups was observed,and the levels of peripheral blood,sex hormones,insulin resistance and oxidative stress were detected before and after treatment for 3 months.Results:The total effective rate in the observation group was better than that in the control group(P<0.01);After intervention,serum LH,FSH,E_(2) and LH/FSH in the observation group were significantly different from those before intervention.The D values of serum LH,FSH,LH/FSH and E_(2) before and after intervention were significantly different between the two groups(P<0.01);Comparing the level of androgen,the serum A4 and T in the observation group were significantly different from those before intervention(P<0.01);After intervention,there was a significant difference in serum A4 and T between the two groups(P<0.01),and there was a significant difference in D value between the two groups before and after intervention;There was a difference in insulin resistance in the observation group before and after intervention(P<0.05),and there was a significant difference in D value between the two groups before and after intervention(P<0.01);After the intervention,the serum SOD,MDA,ROS in the observation group were significantly different from those before the intervention;After intervention,the results of serum SOD and ROS in the observation group were significantly different from those in the control group;There was no significant difference in serum MDA results.There were significant differences in SOD,MDA,ROS between the two groups before and after intervention.Conclusion:Electroacupuncture can improve oxidative stress injury,insulin resistance and hyperandrogenism in PCOS patients. 展开更多
关键词 Polycystic Ovary Syndrome ELECTROACUPUNCTURE Kidney deficiency and phlegm dampness Oxidative stress Insulin resistance HYPERANDROGENISM Clinical curative effect
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The Role and Significance of Brain-gut Peptide and Its Receptor's Expression in the Mechanism's Explanation of Cleaning Away Heat and Dampness
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作者 吕文亮 邱明义 《中医药学刊》 2004年第8期1455-1458,共4页
Cleaning away Heat and Dampness is one of the general methods in treating the syndrome of the Spleen and Stomach’s damp heat in Febrile Diseases,and its efficacy of invigorating the spleen regulating the stomach is i... Cleaning away Heat and Dampness is one of the general methods in treating the syndrome of the Spleen and Stomach’s damp heat in Febrile Diseases,and its efficacy of invigorating the spleen regulating the stomach is involved in regulation of gastrointestinal motility.Many factors and systems act as the regulation,including Brain-gut peptide,which quantitative change in the gastrointestinal tissues and plasma can reflex the functions of gastrointestinal motility.So carrying on an investigation into the relation between brain-gut peptide and its receptors and gastrointestinal dyskinesia in the syndrome of damp heat in the spleen and stomach has its relevant to the explanation of the mechanism of cleaning away Heat and Dampness. 展开更多
关键词 综合症 胃肠功能障碍 发热
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Exploration and Study of Jianpi Qushi Powder Combined with Standard Anti HP Quadruple Therapy in the Treatment of HP Infectious Gastritis of Spleen Deficiency and Dampness Stagnation Type 被引量:1
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作者 Qiangcai Mai Guosheng Su +9 位作者 Lihua Qin Shoulan Gong ] Miaoling Liang Yu Gan Xinrong Huang Xiaoye Su Buqing Su Xiuling Wei Min Yang 《Natural Science》 2022年第2期56-61,共6页
Objective: To explore the therapeutic effect of traditional Chinese medicine Jianpi Qushi powder combined with standard anti-HP quadruple therapy in the treatment of HP infectious gastritis with spleen deficiency and ... Objective: To explore the therapeutic effect of traditional Chinese medicine Jianpi Qushi powder combined with standard anti-HP quadruple therapy in the treatment of HP infectious gastritis with spleen deficiency and dampness stagnation. Methods: From January 2020 to December 2021, 223 patients with laboratory-confirmed HP infection who were admitted to the Outpatient and Inpatient Department of Internal Medicine in our hospital were selected as the research objects and randomly divided into two groups. 101 patients in the control group were given standard anti HP quadruple therapy;122 cases in the treatment group were given traditional Chinese medicine Jianpi Qushi powder combined with standard anti HP quadruple therapy. The two groups were rechecked carbon breath test after the designed course of treatment, and the curative effects of the two groups were compared. Results: 113 cases in the treatment group were cured by traditional Chinese medicine Jianpi Qushi powder combined with standard anti HP quadruple therapy, and the cure rate was 92.62%. 84 cases in the control group were cured by standard anti HP quadruple therapy, and the cure rate was 83.17%, χ<sup>2</sup> = 4.7955, P = 0.0285, the difference was statistically significant (P < 0.05). Conclusion: Traditional Chinese medicine Jianpi Qushi powder combined with standard anti HP quadruple therapy in the treatment of HP infectious gastritis with spleen deficiency and dampness stagnation is one of the best treatment schemes for HP infection. The results of this study achieve the best clinical treatment effect, and provide a more valuable and reliable method for the treatment of gastropathy in clinical internal medicine, which is worthy of popularization and application. 展开更多
关键词 Traditional Chinese Medicine Jianpi Qushi Powder Helicobacter Pylori Standard Anti HP Quadruple Therapy Spleen Deficiency dampness Stagnation Type GASTRITIS
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Pullback attractor of 2D nonautonomous g-Navier-Stokes equations with linear dampness
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作者 姜金平 候延仁 王小霞 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第2期151-166,共16页
The pullback attractors for the 2D nonautonomous g-Navier-Stokes equations with linear dampness axe investigated on some unbounded domains. The existence of the pullback attractors is proved by verifying the existence... The pullback attractors for the 2D nonautonomous g-Navier-Stokes equations with linear dampness axe investigated on some unbounded domains. The existence of the pullback attractors is proved by verifying the existence of pullback D-absorbing sets with cocycle and obtaining the pullback :D-asymptotic compactness. Furthermore, the estimation of the fractal dimensions for the 2D g-Navier-Stokes equations is given. 展开更多
关键词 pullback attractor g-Navier-Stokes equation pullback asymptotic com-pactness fractal dimension linear dampness
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Optimization on microstructure,mechanical properties and damping capacities of duplex structured Mg–8Li–4Zn–1Mn alloys 被引量:2
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作者 Tongtong Cao Yong Zhu +7 位作者 Yuyang Gao Yan Yang Gang Zhou Xiaofei Cui Chen Wen Bin Jiang Xiaodong Peng Fusheng Pan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第5期949-958,共10页
Optimizing the mechanical properties and damping capacity of the duplex-structured Mg–Li–Zn–Mn alloy by tailoring the microstructure via hot extrusion was investigated.The results show that the Mg–8Li–4Zn–1Mn al... Optimizing the mechanical properties and damping capacity of the duplex-structured Mg–Li–Zn–Mn alloy by tailoring the microstructure via hot extrusion was investigated.The results show that the Mg–8Li–4Zn–1Mn alloy is mainly composed ofα-Mg,β-Li,Mg–Li–Zn and Mn phases.The microstructure of the test alloy is refined owing to dynamic recrystallization(DRX)during hot extrusion.After hot extrusion,the crushed precipitates are uniformly distributed in the test alloy.The yield strength(YS),ultimate tensile strength(UTS),and elongation(EL)of as-extruded alloy reach 156 MPa,208 MPa,and 32.3%,respectively,which are much better than that of as-cast alloy.Furthermore,the as-extruded and as-cast alloys both exhibit superior damping capacities,with the damping capacity(Q^(-1))of 0.030 and 0.033 at the strain amplitude of 2×10^(-3),respectively.The mechanical properties of the test alloy can be significantly improved by hot extrusion,whereas the damping capacities have no noticeable change,which indicates that the duplex-structured Mg–Li alloys with appropriate mechanical properties and damping properties can be obtained by alloying and hot extrusion. 展开更多
关键词 magnesium–lithium alloys hot extrusion MICROSTRUCTURE mechanical properties damping capacity
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Research Progress of Jianpi Qushi Powder Combined with Standard Anti Hp Quadruple Therapy in the Treatment of Hp Infectious Gastritis with Spleen Deficiency and Dampness Stagnation 被引量:1
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作者 Qiangcai Mai Shoulan Gong +1 位作者 Guosheng Su Lihua Qin 《Chinese Medicine》 2022年第1期15-21,共7页
Stomach Helicobacter pylori infection is one of the common gastric diseases. Helicobacter pylori infectious gastritis of spleen deficiency and dampness stagnation is a relatively intractable chronic disease. In recent... Stomach Helicobacter pylori infection is one of the common gastric diseases. Helicobacter pylori infectious gastritis of spleen deficiency and dampness stagnation is a relatively intractable chronic disease. In recent years, traditional Chinese medicine methods have emerged one after another in the treatment of gastric Helicobacter pylori infection. By collecting references, the author reviewed the clinical characteristics of gastric Helicobacter pylori infection and the new progress of traditional Chinese medicine treatment. 展开更多
关键词 Traditional Chinese Medicine Jianpi Qushi Powder Quadruple Therapy Spleen Deficiency dampness Stagnation Type Helicobacter Pylori Infection GASTRITIS
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A marine gravimeter based on electromagnetic damping and its tests in the South China Sea 被引量:1
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作者 Pengfei WU Lin WU +3 位作者 Lifeng BAO Long WANG Bo WANG Danling TANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第2期792-803,共12页
A new gravity sensor based on electromagnetic damping for the JMGrav marine gravimeter is presented.The new gravity sensor considered the advanced construction methods of the electromagnetic damping system of the grav... A new gravity sensor based on electromagnetic damping for the JMGrav marine gravimeter is presented.The new gravity sensor considered the advanced construction methods of the electromagnetic damping system of the gravimeter.The design features of the new system are discussed and the research survey data in the South China Sea are shown.Numerical simulations are applied to model the magnetic and mechanical characteristics of the system using finite element analysis and to evaluate the force distribution and the resulting damping effects.The performance characteristics of the system were tested on a motion simulator in laboratory,and the gravimeter was subjected to vertical accelerations of up to 100 Gal in 1-1000 s.It was found that the amplitude reduction of vertical accelerations in 3-15 s is 30-45 dB,with a time lag of 2-5 s,while the effect on gravity in period greater than 600 s is less than 0.5 dB,with a time lag of less than 100 s.The accelerations cause discrepancies of approximately only 1 mGal between the static value and the mean dynamic value.The sea tests were conducted in September 2020.Gravity measurements were taken with a JMGrav marine gravimeter onboard the R/V Dongfanghong 3,and the effective survey line exceeded 2000 km.Completely irregular accelerations with peaks up to 100 Gal yielded a reduction of approximately 40 dB in amplitude.The survey data were evaluated using ocean gravity field models and grid line tests.The results show that the accuracy of the gravity measurements is better than 2 mGal. 展开更多
关键词 electromagnetic damping JMGrav marine gravimeter marine gravity survey
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Indoor Exposure to Mould and Dampness in Infancy and Its Association to Persistent Atopic Dermatitis in School Age: Results from the Greek ISAAC II Study
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作者 Papadopoulou Athina Mermiri Despina +3 位作者 Xatziagorou Elpida Lambidi Stavroula Cratziou Christina Tsanakas Ioannis 《Open Journal of Pediatrics》 2016年第1期75-81,共7页
Introduction: The presence of mould as a source of perennial allergens and bacteria products has been related to the appearance of respiratory symptoms in several studies. Yet, its role in eczema has not been elucidat... Introduction: The presence of mould as a source of perennial allergens and bacteria products has been related to the appearance of respiratory symptoms in several studies. Yet, its role in eczema has not been elucidated. The aim of this study was to investigate the association between exposure to indoor visible molds/dampness and the manifestation of eczema in children. Methods: The study is part of the Greek contribution to ISAAC IΙ that includes 2023 students of randomly selected public primary schools in Athens and Thessaloniki, aged 9 - 10 years old. The children represented a general population sample and were evaluated according to ISAAC II questionnaire, validated for Greek language. Additionally, skin prick tests to aero-allergens were performed and children were examined for active skin lesions. Results: 13% had suffered from eczema in the past, 9% had current and 2% had atopic eczema (positive at least one skin prick test). Out of the children examined, half reported that eczema first appeared after the age of five years old whereas 70% mentioned persistence of eczema. Dampness was reported in 10.8% and visible mould in 6.4% of all cases during infancy, while continued exposure until the age of 10 years old was reported in 38% and 33% out of them respectively. 10.8% of the sensitized children were positive to house dust mites and Alternaria, however, sensitization was not related to indoor exposure. In logistic regression analysis evaluating 20 environmental risk factors, a significant association was noted between the presence of indoor visible mold and dampness in infancy, and the presence of current eczema OR 1, 89 (95%CI 1.18 - 3.03). This association remained significant irrespective of the family history of eczema and sensitization. Conclusions: Frequently eczema first appears at early school age. The presence of visible mold and dampness at home during infancy appears to be an initial enhancing risk factor for the development but also for the persistence of the disease throughout school age. 展开更多
关键词 Persistent Atopic Dermatitis MOULD dampness ISAAC II Children
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Analysis of treatment strategies of traditional Chinese medicine for COVID-19 in tropical regions based on the pathogens of dampness and heat
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作者 Xian Wang Wen-Long Zhang +3 位作者 Chang Liu Mi Li Kai Li Yi-Qiang Xie 《Journal of Hainan Medical University》 2020年第9期10-14,共5页
Objective:To summarize the treatment strategies of Traditional Chinese Medicine(TCM)for COVID-19 in tropical regions based on the pathogens of dampness and heat.Methods:For heat pathogen,analyzing heat in the superfic... Objective:To summarize the treatment strategies of Traditional Chinese Medicine(TCM)for COVID-19 in tropical regions based on the pathogens of dampness and heat.Methods:For heat pathogen,analyzing heat in the superficies,lung and Yang Ming based on the different locations.Based on the progress of the disease,analyzing the stage of toxin and Qi deficiency induced by heat.For dampness pathogen,analyzing endogenous and external dampness based on the different locations.Analyzing dampness pathogen's special disease location—Moyuan and special symptom of dry cough with less sputum caused by sticky and stagnant characteristic of dampness.Results:The treatment strategies for heat and dampness pathogen were summarized.Conclusion:In the tropics,the pathogens of dampness and heat occur frequently and clinical treatments need to be dialectical. 展开更多
关键词 Pathogens of dampness and heat TROPICS COVID-19 TCM Treatment strategies
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Clinical effect of enriching qi, activating blood circulation, clearing away dampness and heat combined with western medicine in the treatment of idiopathic membranous nephropathy: A meta-analysis
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作者 Zheng-Mei Zhang Zi-Long Shen +1 位作者 Mei-Jie Wang Jing Li 《Journal of Hainan Medical University》 2022年第10期33-41,共9页
Objective:To systemically review the efficacy and safety about the method of enriching qi,activating blood circulation,clearing away dampness and heat combined with western medicine in the therapy of patients with idi... Objective:To systemically review the efficacy and safety about the method of enriching qi,activating blood circulation,clearing away dampness and heat combined with western medicine in the therapy of patients with idiopathy membranous nephropathy(IMN).Methods:We collected the randomized controlled trials(RCTs)of enriching qi,activating blood circulation,clearing away dampness and heat for the treatment of IMN from Pub Med,The Cochrane Library,Medline,China National Knowledge Infrastructure(CNKI),China Biology Medicine disc(CBM),Wanfang Data and Wiper Databases.Bias of risk of retrieval literature was evaluated according to Cochrane Collaboration standard,and Review Manager 5.3 software was used for statistical analysis.Results:Fourteen trials(836 participants)were included in the meta-analysis.This kind of traditional Chinese method combined with western medicine in the treatment of IMN exerted statistical differences in reducing 24-hour urinary protein[WMD=-0.97,95%CI(-1.30,-0.65),Z=5.86(P<0.00001)]and elevating serum albumin[WMD=3.83,95%CI(2.10,5.57),Z=4.33,P<0.0001],lowering serum cholesterol[WMD=-0.82,95%CI(-1.08,-0.56),Z=6.18,P<0.00001],triglycerides[WMD=-0.39,95%CI(-0.67,-0.11),Z=2.77,P=0.006]and reducing the risk of adverse events[OR=0.29,95%CI[0.16,0.50],Z=4.35,P<0.0001]in the patients with IMN as compared with controls.However,there was no statistically significant difference between the method and controls when combining all trials in serum creatinine[WMD=-5.52,95%CI(-18.06,7.03),Z=0.86,P=0.39],when combining all trials in urea nitrogen[WMD=-0.90,95%CI(-2.22,0.41),Z=1.35,P=0.18].Conclusion:The method of enriching qi,activating blood circulation,clearing away dampness and heat combined with western medicine exerts certain advantages and better safety in treating patients with IMN.However,for the inferiority of the included studies,the conclusion still needs high-quality and large-sample prospective randomized controlled trials to verify. 展开更多
关键词 Idiopathic membranous nephropathy META-ANALYSIS Enriching qi Activating blood circulation Clearing away dampness and heat
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Damping performance of SiC nanoparticles reinforced magnesium matrix composites processed by cyclic extrusion and compression
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作者 Mahmoud Ebrahimi Li Zhang +2 位作者 Qudong Wang Hao Zhou Wenzhen Li 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第5期1608-1617,共10页
This work dealt with the damping performance and its underlying mechanism in SiC nanoparticles reinforced AZ91D composite(SiC_(np)/AZ91D)processed by cyclic extrusion and compression(CEC).It was found that the CEC pro... This work dealt with the damping performance and its underlying mechanism in SiC nanoparticles reinforced AZ91D composite(SiC_(np)/AZ91D)processed by cyclic extrusion and compression(CEC).It was found that the CEC process significantly affects the damping performance of the composite due to alterations in the density of dislocations and grain boundaries in the matrix alloy.Although there would be dynamic precipitation of the Mg17Al12 phase during processing which increases the phase interface and limits the mobility of dislocations and grain boundaries.The results also showed that the damping capacity of 1%SiC_(np)/AZ91D composite continuously decreases with adding CEC pass number and it consistently increases with rising the applied temperature.Considering the first derivative of the tanδ-T curve,the dominant damping mechanism based on test temperature can be divided into three regions.These three regions are as follows(i)dislocation vibration of the weak pinning points(≤T_(cr)),(ii)dislocation vibration of the strong pinning points(T_(cr)∼T_(V)),and(iii)grain boundary/interface sliding(≥T_(V)) 展开更多
关键词 Metal matrix composite SiC nanoparticles Severe plastic deformation Temperature-dependent damping curves damping mechanism
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Effects of Cangfudaotan Tang on Expression of Organic Anion Transporting Polypeptide (oatp2b1) in Liver and Kidney Tissues of Rats with Phlegm Dampness Type Polycystic Ovary Syndrome (PCOS)
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作者 Ke Chen Aizhen Pan +2 位作者 Jianjun Li Kefang Chen Xiangping Hou 《Chinese Medicine》 2016年第4期166-174,共10页
Objective: To explore the effect of Cangfudaotan Tang on phlegm dampness type of PCOS and the role of oatp2b1 in transportation and transformation of phlegm dampness. Methods: 36 SD female rats were randomly divided i... Objective: To explore the effect of Cangfudaotan Tang on phlegm dampness type of PCOS and the role of oatp2b1 in transportation and transformation of phlegm dampness. Methods: 36 SD female rats were randomly divided into three groups: blank control group, model group and Cangfudaotan Tang group, 12 cases in each one. After PCOS rat models were made, rats of Cangfudaotan Tang group were treated with Cangfudaotan Tang (1.42 g/kg/d) by intragastric administration for 14 days;blank control and model group were given with isodose saline. The expression of oatp2b1 mRNA/Protein in liver and kidney tissues was measured and the level of testosterone (T), follicle stimulating hormone(FSH), estradiol (E<sub>2</sub>), luteinizing hormone(LH), Serum total cholesterol (TG), Triacylglycerols (TC), high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C) were detected at the same time. Results: Compared with blank control group, the expression of oatp2b1 mRNA and the level of TC, TG, LDL, LH, FSH, T in model group were significantly increased (P < 0. 05), while the level of HDL was significantly decreased (P < 0. 05);compared with model group, the expression of oatp2b1 mRNA and the level of TC, TG, LDL in Cangfudaotan Tang group were significantly lowered (P < 0.05);the level of HDL was significantly higher;the oatp2b1 protein in kidney and liver tissues had different degrees of expression, while there was no statistical significance among the three groups. Conclusions: Oatp2b1 might be one of the material bases participating in transportation and transformation of phlegmy dampness. The mechanism of Cangfudaotan Tang treating phlegm dampness type of PCOS may be achieved by regulating the expression of oatp2b1. 展开更多
关键词 Cangfudaotan Tang Polycystic Ovary Syndrome Phlegm dampness Organic Anion Transporting Polypeptide Oatp2b1
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A Review of Influencing Factors of Damping Properties of High Manganese Steel
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作者 Chao Chen Jiale Wang +2 位作者 Jianyu Jiao Fengmei Bai Guangwen Zheng 《Journal of Materials Science and Chemical Engineering》 CAS 2023年第3期52-64,共13页
High manganese steel has wide prospects in industry due to their excellent mechanical and damping properties. The quenching structures of high manganese steel are ε-martensite, γ-austenite and α'-martensite. Re... High manganese steel has wide prospects in industry due to their excellent mechanical and damping properties. The quenching structures of high manganese steel are ε-martensite, γ-austenite and α'-martensite. Researches show that the damping properties of high manganese steel are related to these microstructures. Besides, there are many ways to improve the damping property of damping alloys. This paper reviews the damping mechanism and the influences of the ad-dition of alloying elements, heat treatment, pre-deformation and other factors on their damping performance, hoping to provide methods and ideas for the study of damping properties of high manganese steel. . 展开更多
关键词 High Manganese Steel damping Properties Alloying Elements Heat Treatment DEFORMATION
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