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A comparative study of the anti-fatigue activity of extracts from different parts of Cistanche tubulosa(Schenk)Wight
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作者 Jianteng Dong Junjun Li +7 位作者 Yizhou Liu Lingwen Cui Xiangning Liu Gang Wang Qixin Wang David N.Criddle Pengfei Tu Chun Li 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第2期222-231,共10页
Objective:To evaluate the anti-fatigue effects of different extracts from Cistanche tubulosa(Schenk)Wight(C.tubulosa,Rou Cong Rong),focusing on central and exercise-induced fatigue in mice.This study investigated the ... Objective:To evaluate the anti-fatigue effects of different extracts from Cistanche tubulosa(Schenk)Wight(C.tubulosa,Rou Cong Rong),focusing on central and exercise-induced fatigue in mice.This study investigated the pharmacological effects of the total oligosaccharides,polysaccharides,and phenylethanoid glycosides(CPhGs)extracted from C.tubulosa.Methods: Models of sleep deprivation and forced swimming fatigue were established to simulate central and exercise-induced fatigue.The mice were treated with different extracts of C.tubulosa,and their effects were assessed using behavioral tests to measure exercise capacity,learning,and memory function.Biochemical analyses were performed to evaluate the changes in serum and brain neurotransmitter levels,liver and muscle glycogen storage,and various fatigue-related biomarkers.Results: This study found that treatment with C.tubulosa extract improved exercise capacity,learning,and memory in mice.Total oligosaccharides from C.tubulosa enhanced adrenocorticotropic hormone,cholinesterase,and thyroid-stimulating hormone levels,reduced cortisol levels in central fatigue models,and ameliorated biochemical markers of exercise-induced fatigue,including lowering lactic acid,blood urea nitrogen,and malondialdehyde levels.Among the tested extracts,the total oligosaccharides showed the most comprehensive anti-fatigue effects.Conclusion: The anti-fatigue effects of C.tubulosa,particularly those of its total oligosaccharides,are pronounced in both central and exercise-induced fatigue.These effects are mediated by the regulation of neurotransmitter levels,enhancement of glycogen storage,and improvement of antioxidant enzyme activity,suggesting potential therapeutic benefits in fatigue-related conditions. 展开更多
关键词 Cistanche tubulosa anti-fatigue Central fatigue Exercise fatigue OLIGOSACCHARIDES
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Anti-fatigue effects of salidroside in mice 被引量:31
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作者 Ma Li Cai Donglian +3 位作者 Li Huaixing Tong Bende Song Lihua Wang Ying 《Journal of Medical Colleges of PLA(China)》 CAS 2008年第2期88-93,共6页
Objective: To study the anti-fatigue effects of salidroside in mice. Methods: Totally 120 normal male Kunming mice were randomized into 5 groups (4 salidroside intervention groups and the control group) based on b... Objective: To study the anti-fatigue effects of salidroside in mice. Methods: Totally 120 normal male Kunming mice were randomized into 5 groups (4 salidroside intervention groups and the control group) based on body weight. The control group was given distilled water and the 4 intervention groups were given various doses of salidroside (60, 180, 360, 720 mg/kg) for 15 consecutive days, respectively. The levels of lactate, serum urea nitrogen, muscle and liver glycogen, the longest swimming time and hemoglobin were determined before and after swimming test. Results: Different doses of salidroside significantly lengthened the swimming time and increased the contents of hemoglobin and muscle and liver glycogen, while reducing that of lactate in blood significantly compared with control group, especially in the 180 mg/kg salidroside group. Conclusion: Salidroside has noticeable anti-fatigue effect on mice. These effects were dose-dependent, and the strongest effect on most biomarkers was seen with an intermediate dose. 展开更多
关键词 SALIDROSIDE anti-fatigue
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Anti-Fatigue Effect of Blended <i>Camellia oleifera Abel</i>Tea Oil and Ge-132 in Mice 被引量:5
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作者 Lisong Hu Xuezhi Fang +1 位作者 Menghao Du Jingping Zhang 《Food and Nutrition Sciences》 2015年第15期1479-1487,共9页
Nowadays, people are busier and busier for working and living, and suffer a lot of pressure on their body or mind. Therefore, people are prone to have fatigue activity and decrease their working efficiency and happine... Nowadays, people are busier and busier for working and living, and suffer a lot of pressure on their body or mind. Therefore, people are prone to have fatigue activity and decrease their working efficiency and happiness. It was reported that fatigue is a common symptom in the community, with up to half of the general population complaining of fatigue. More and more researchers devoted themselves to studying natural active ingredients in organism as the anti-fatigue drugs to release fatigue symptom. However, these natural ingredients were difficult to obtain from plants, animals and microorganisms by separating and purifying. In addition, some active substances have many side effects. In our study, we employed tea seed oil as main ingredients blended with bis-(carboxyethylgermanium) sesquioxide (Ge-132) to investigate the effects of anti-fatigue on mice by administrating mice with low dose, intermediate dose and high dose of tea seed oil complex for 0, 2 or 4 weeks. The specific tests of studying effects of anti-fatigue were body weight, weight-loaded force swimming, blood urea nitrogen, blood lactic acid and hepaticglycogen. And the results showed that appropriate level of tea seed oil complex could decrease the body weight and prolong the weight-loaded swimming time, and had an active effect on the bloodurea nitrogen, hepatic glycogen and blood lactic acid level mice, which significantly embodied the anti-fatigue activity of tea seed oil complex. 展开更多
关键词 TEA Seed OIL GE-132 anti-fatigue Blending
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Evaluation of silymarin extract from Silybum marianum in mice: anti-fatigue activity 被引量:2
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作者 Luming Jia Fei Zhao 《Food Science and Human Wellness》 SCIE 2022年第4期914-921,共8页
Silymarin has been used for centuries for its hepatoprotective properties. The specific objective of this study was to evaluate the anti-fatigue properties of silymarin. The silymarin was administered orally at doses ... Silymarin has been used for centuries for its hepatoprotective properties. The specific objective of this study was to evaluate the anti-fatigue properties of silymarin. The silymarin was administered orally at doses of 50, 100, and 200 mg/kg for 4 weeks;the fatigue level and exercise performance were evaluated using exhaustive swimming time and pole-climbing time, as well as levels of plasma lactate, ammonia, glucose, creatine kinase(CK), serum urea nitrogen(SUN), blood lactic acid(BLA), muscle glycogen(MG), and liver glycogen(LG) contents after an intensive swimming session. The results demonstrated that silymarin treatment decreased the BLA and SUN levels while increased the LG and MG levels. In addition, silymarin decreased plasma lactate and ammonia levels and CK activity after swimming test, this is related to the mechanism that increases energy storage(as glycogen) and release(as blood glucose), and decreases plasma levels of lactate, ammonia, and CK. The observation of the skeletal muscle structures of mice also confirmed that skeletal muscles became more damaged in the control group compared with the silymarin-treated mice after prolonged endurance exercise. Therefore, it is reasonable to infer that silymarin may bear potential pharmacological effects in combating fatigue. 展开更多
关键词 Silybum marianum SILYMARIN anti-fatigue Exhaustion exercise
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Present Situation of the Anti-Fatigue Processing of High-Strength Steel Internal Thread Based on Cold Extrusion Technology:A Review 被引量:5
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作者 Hong MIAO Cheng JIANG +2 位作者 Sixing LIU Shanwen ZHANG Yanjun ZHANG 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第2期231-240,共10页
The adoption of cold-extrusion forming for internal thread net forming becomes an important component of anti-fatigue processing with the development of internal thread processing towards high performance, low cost an... The adoption of cold-extrusion forming for internal thread net forming becomes an important component of anti-fatigue processing with the development of internal thread processing towards high performance, low cost and low energy consumption. It has vast application foreground in the field of aviation, spaceflight, high speed train and etc. The internal thread processing and anti-fatigue manufacture technology are summarized. In terms of the perspective of processing quality and fatigue serving life, the advantages and disadvantages of the processing methods from are compared. The internal thread cold-extrusion processing technology is investigated for the purpose of improving the anti-fatigue serving life of internal thread. The superiorities of the plastic deformation law and surface integrity of the metal layer in the course of cold extrusion for improving its stability and economy are summed up. The proposed research forecasts the develop- ment tendency of the internal thread anti-fatigue manufacturing technology. 展开更多
关键词 High-strength steel · Internal thread · Coldextrusion · anti-fatigue · Surface integrity
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The study of Gongshisong' s anti-fatigue active site sifting
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《中国药理学通报》 CAS CSCD 北大核心 2015年第B11期130-130,共1页
Aim To investigate the influence of the Gongshisong extract of different extraction parts on mice sports fatigue index. Method The mice were randomly divided into blank group, model group, the Gongshisong extract gro... Aim To investigate the influence of the Gongshisong extract of different extraction parts on mice sports fatigue index. Method The mice were randomly divided into blank group, model group, the Gongshisong extract group (petroleum ether, chloroform, ethyl acetate, n-butanol, the aqueous layer) and the positive control group. The mice in different groups were fed with corresponding Gongshisong extract liquid 2.5 g kg^-1 d^-1 once per day for consecutively 7 days. The blank group and model group were given 1% sodium carboxymethyl cellulose so- lution, the positive control group was administered with Rhodiola 0.59 g · kg^-1· d^-1 After the last administered each group of mice were determined of weihgt-loading swimming time, liver glycogen and muscle glycogen content, and urea nitrogen, lactic acid and creatine kinase in 90min mice after swimming content in blood. Result Com- pared with the blank group, the petroleum ether extract of Gongshisong could significantly prolong the swimming time of mice (P 〈 0.05), enhancing the mice muscle glycogen reserves (P 〈 0.05), and reduce the level of urea nitrogen and creatine kinase in mice after swimming (P 〈 0.05). Butanol extraction liquid of Gongshisong can ob- viously prolong the swimming time of mice (P 〈 0.05), increasing the reserves of glycogen in mice (P 〈 0.05), decreasing the level of urea nitrogen in mice and blood lactate after swimming (P 〈 0.05 ). Water extract of Gong- shisong could significantly prolong the swimming time of mice (P 〈 0.05) , increasing muscle glycogen storage (P 〈0.05), reducing the level of blood lactic acid in mice after swimming (P 〈 0.05). Ethyl acetate extract of Gongshisong could significantly prolong the swimming time of mice (P 〈 0.05) , and increase the reserves of glyco- gen in mice (P 〈0. 05). Conclusion Comprehensive analysis, the petroleum ether, n-butanol and water site of Gongshisong is better anti fatigue active site. 展开更多
关键词 Gongshisong anti-fatigue weight-loading SWIMMING GLYCOGEN LACTIC acid UREA nitrogen creatinekinase
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Dual-Defect Engineering Strategy Enables High-Durability Rechargeable Magnesium-Metal Batteries 被引量:1
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作者 Fuyu Chen Bai‑Qing Zhao +8 位作者 Kaifeng Huang Xiu‑Fen Ma Hong‑Yi Li Xie Zhang Jiang Diao Jili Yue Guangsheng Huang Jingfeng Wang Fusheng Pan 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期449-461,共13页
Rechargeable magnesium-metal batteries(RMMBs)are promising next-generation secondary batteries;however,their development is inhibited by the low capacity and short cycle lifespan of cathodes.Although various strategie... Rechargeable magnesium-metal batteries(RMMBs)are promising next-generation secondary batteries;however,their development is inhibited by the low capacity and short cycle lifespan of cathodes.Although various strategies have been devised to enhance the Mg^(2+)migration kinetics and structural stability of cathodes,they fail to improve electronic conductivity,rendering the cathodes incompatible with magnesium-metal anodes.Herein,we propose a dual-defect engineering strategy,namely,the incorporation of Mg^(2+)pre-intercalation defect(P-Mgd)and oxygen defect(Od),to simultaneously improve the Mg^(2+)migration kinetics,structural stability,and electronic conductivity of the cathodes of RMMBs.Using lamellar V_(2)O_(5)·nH_(2)O as a demo cathode material,we prepare a cathode comprising Mg_(0.07)V_(2)O_(5)·1.4H_(2)O nanobelts composited with reduced graphene oxide(MVOH/rGO)with P-Mgd and Od.The Od enlarges interlayer spacing,accelerates Mg^(2+)migration kinetics,and prevents structural collapse,while the P-Mgd stabilizes the lamellar structure and increases electronic conductivity.Consequently,the MVOH/rGO cathode exhibits a high capacity of 197 mAh g^(−1),and the developed Mg foil//MVOH/rGO full cell demonstrates an incredible lifespan of 850 cycles at 0.1 A g^(−1),capable of powering a light-emitting diode.The proposed dual-defect engineering strategy provides new insights into developing high-durability,high-capacity cathodes,advancing the practical application of RMMBs,and other new secondary batteries. 展开更多
关键词 Rechargeable magnesium-metal batteries Dual-defect engineering Vanadium-based cathode High durability Lamellar structure
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The Preparation Technology Research and Composition Analysis of Anti-fatigue Yikangshu Granules
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作者 Kun TANG Tong LIN +2 位作者 Chundan ZHANG Yanxia LU Shunxing GUO 《Medicinal Plant》 CAS 2021年第5期46-50,共5页
[Objectives]To optimize the preparation technology of Yikangshu granule,an anti-fatigue health food.[Methods]The process was studied from three aspects(raw material extraction,excipient selection and forming process),... [Objectives]To optimize the preparation technology of Yikangshu granule,an anti-fatigue health food.[Methods]The process was studied from three aspects(raw material extraction,excipient selection and forming process),and then it was verified in pilot production,and the content of the three components of the product was determined.[Results]The optimum production process of the formula granules was as follows:raw materials were extracted(adding 1∶9 water,extracting twice,2.5 h each time);vacuum concentration;adding excipients and mixing after vacuum drying,crushing and sieving;granulation of 75%ethanol sifted by a 20-mesh sieve;drying at 60℃,sifting through 14-mesh,and packaging.The average content of products obtained was as follows:crude polysaccharides(3204 mg/100 g),total saponins(2295 mg/100 g),astragaloside A(21 mg/100 g).[Conclusions]The optimized preparation technology is stable and feasible,and has a quality that can be controlled,which can provide a reference for the development of health food in food industry. 展开更多
关键词 anti-fatigue Health food Formula granules Technology research Composition analysis
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Anti-fatigue Effect of Water Extract from Centella asiatica(L.)Urban on Mice
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作者 Chunmei MO Jinye LIN +5 位作者 Yanfang MA Jiajie ZHOU Ling LIANG Nian LIN Suoyi HUANG Gang XIAO 《Medicinal Plant》 CAS 2023年第1期48-49,54,共3页
[Objectives]To study the anti-fatigue effect of water extract from Centella asiatica(L.)Urban on mice.[Methods]After intragastric administration of low,medium and high concentration of water extract from Centella asia... [Objectives]To study the anti-fatigue effect of water extract from Centella asiatica(L.)Urban on mice.[Methods]After intragastric administration of low,medium and high concentration of water extract from Centella asiatica(L.)Urban for 14 d,the rotarod time and the content of serum lactic acid in mice were determined,respectively.[Results]Compared with the control group,the rotarod time of mice in the low and medium concentration groups was significantly prolonged(P<0.05),but there was no significant difference between the control group and the high concentration group;the content of serum lactic acid in the medium concentration group was significantly lower than that in the control group(P<0.01),but there was no significant difference between low concentration group and high concentration group and the control group.[Conclusions]A certain concentration of water extract from Centella asiatica(L.)Urban had a good anti-fatigue effect. 展开更多
关键词 Centella asiatica(L.)Urban MICE anti-fatigue
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Anti-fatigue Effect of L-arginine Complex Preparation on Mice
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作者 Qian Tan Xiaodong Dong +5 位作者 Junfeng Zhai Yaxian Gu Honghui Hao Wen Ren Chuanbao Gong Chengqiang Yin 《Proceedings of Anticancer Research》 2019年第1期1-4,共4页
Objective:To investigate the anti-fatigue effect of L-arginine complex preparation on mice.Methods:The experimental mice were divided into a blank group,low dose group,medium dose group and high dose group.L-arginine ... Objective:To investigate the anti-fatigue effect of L-arginine complex preparation on mice.Methods:The experimental mice were divided into a blank group,low dose group,medium dose group and high dose group.L-arginine complex preparation mice were intragastrically administered for 30 days,and the mice were tested for exhaustive swimming time.At the same time,contents of plasma lactic acid,lactate dehydrogenase,urea nitrogen and hepatic glycogen were measured.Results:Compared with the blank control group,the weight-bearing swimming time and hypoxia-tolerant survival time of the low,middle and high dose groups was significantly increased(P<0.05).Whereas,the serum urea nitrogen levels and lactose content were significantly decreased(P<0.05).However,compared with the blank control group,the liver glycogen content of the middle and high dose groups was increased significantly(P<0.05),and there was no significant difference in the low dose group.Conclusion:The L-arginine complex preparation has an anti-fatigue function in mice. 展开更多
关键词 L-ARGININE COMPLEX anti-fatigue
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Local coordination and electronic interactions of Pd/MXene via dual‐atom codoping with superior durability for efficient electrocatalytic ethanol oxidation
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作者 Zhangxin Chen Fan Jing +7 位作者 Minghui Luo Xiaohui Wu Haichang Fu Shengwei Xiao Binbin Yu Dan Chen Xianqiang Xiong Yanxian Jin 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期166-177,共12页
Catalyst design relies heavily on electronic metal‐support interactions,but the metal‐support interface with an uncontrollable electronic or coordination environment makes it challenging.Herein,we outline a promisin... Catalyst design relies heavily on electronic metal‐support interactions,but the metal‐support interface with an uncontrollable electronic or coordination environment makes it challenging.Herein,we outline a promising approach for the rational design of catalysts involving heteroatoms as anchors for Pd nanoparticles for ethanol oxidation reaction(EOR)catalysis.The doped B and N atoms from dimethylamine borane(DB)occupy the position of the Ti_(3)C_(2) lattice to anchor the supported Pd nanoparticles.The electrons transfer from the support to B atoms,and then to the metal Pd to form a stable electronic center.A strong electronic interaction can be produced and the d‐band center can be shifted down,driving Pd into the dominant metallic state and making Pd nanoparticles deposit uniformly on the support.As‐obtained Pd/DB–Ti_(3)C_(2) exhibits superior durability to its counterpart(∼14.6% retention)with 91.1% retention after 2000 cycles,placing it among the top single metal anodic catalysts.Further,in situ Raman and density functional theory computations confirm that Pd/DB–Ti_(3)C_(2) is capable of dehydrogenating ethanol at low reaction energies. 展开更多
关键词 durability electronic interactions ethanol oxidation heteroatom codoping Pd/MXene
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Thermophysical, Mechanical and Durability Characterization of Adobe Bricks Reinforced with Fonio (Digitaria exilis) Sounds
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作者 Colbert Babé Etienne Yanné +8 位作者 Souaibou   Mojonda   Lémankréo Bakaiyang Bernard Kola Gustave Assoualaye Layndé Tawé Raidandi Danwé Dieudonné Kidmo Kaoga Noël Djongyang 《Advances in Materials Physics and Chemistry》 CAS 2024年第8期146-164,共19页
Buildings constructed using modern materials such as cement are energy-intensive, facilitate heat transfer and thus promote warming inside the building. However, the Sudano-Sahelian regions have a hot climate occupyin... Buildings constructed using modern materials such as cement are energy-intensive, facilitate heat transfer and thus promote warming inside the building. However, the Sudano-Sahelian regions have a hot climate occupying a large period of the year, thus requiring not only sustainable construction materials, but also which provide thermal comfort in the building by limiting the energy demand for air conditioning. These qualifications are important for sub-Saharan African countries in general and those of the Sudano-Sahelian zone in particular, which need ecological materials with good thermal performance to limit heating inside buildings. This study is an energy recovery of agricultural waste in buildings with a view to offering the populations of the northern regions of Cameroon suitable materials at lower cost for the construction of buildings. The soil used for this study was extracted from the locality of Yagoua where the populations make abundant use of mud bricks. Fonio waste was incorporated at low levels into the earth bricks, particularly at 0%, 1%, 2%, 3%, and 4%, with a view to strengthening their thermophysical and mechanical properties. The results obtained indicate that earth bricks reinforced with 4% waste showed better thermal and mechanical insulation properties compared to other formulations with an improvement of 16% and 78% respectively compared to the unreinforced samples. This research allows us to conclude that fonio waste can be used practically without expense in the building with a view to its energy recovery and will promote not only thermal comfort and the limitation of the energy supply for air conditioning, but the construction of more sustainable buildings with a cleaner environment. 展开更多
关键词 durability Thermal Comfort Building SOIL Fonio Faste
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Influence of Recycled Concrete Fine Powder on Durability of Cement Mortar
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作者 Yadong Bian Xuan Qiu +2 位作者 Jihui Zhao Zhong Li Jiana Ouyang 《Fluid Dynamics & Materials Processing》 EI 2024年第1期45-58,共14页
In this paper,the durability of cement mortar prepared with a recycled-concrete fine powder(RFP)was examined;including the analysis of a variety of aspects,such as the carbonization,sulfate attack and chloride ion ero... In this paper,the durability of cement mortar prepared with a recycled-concrete fine powder(RFP)was examined;including the analysis of a variety of aspects,such as the carbonization,sulfate attack and chloride ion erosion resistance.The results indicate that the influence of RFP on these three aspects is different.The carbonization depth after 30 days and the chloride diffusion coefficient of mortar containing 10%RFP decreased by 13.3%and 28.19%.With a further increase in the RFP content,interconnected pores formed between the RFP particles,leading to an acceleration of the penetration rate of CO_(2)and Cl^(−).When the RFP content was less than 50%,the corrosion resistance coefficient of the compressive strength of the mortar was 0.84-1.05 after 90 days of sulfate attack.But the expansion and cracking of the mortar was effectively alleviated due to decrease of the gypsum production.Scanning electron microscope(SEM)analysis has confirmed that 10%RFP contributes to the formation of a dense microstructure in the cement mortar. 展开更多
关键词 Recycled concrete fine powder cement mortar CARBONIZATION SULFATE chloride ion durability
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Effect of slake durability on time dependent swelling behavior of red-bed siltstone in Sichuan Basin
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作者 JIA Qinji Ruben Angel GALINDO AIRES +1 位作者 LIU Xiaoming XU Haifeng 《Journal of Mountain Science》 SCIE CSCD 2024年第9期3123-3138,共16页
The swelling behavior of red-bed rocks is a significant factor in the abnormal uplift of subgrades for high-speed railways constructed on the red stratum in the Sichuan Basin,China.The prime objective of this paper is... The swelling behavior of red-bed rocks is a significant factor in the abnormal uplift of subgrades for high-speed railways constructed on the red stratum in the Sichuan Basin,China.The prime objective of this paper is to investigate the impact of mineralogical composition,moisture content,and overburden load on the time-dependent unconfined and oedometric swelling behavior of red-bed siltstone in the context of differences in the slake durability.Twenty samples were prepared for the swelling test,with eleven used for the unconfined swelling and slake index tests and nine for the oedometric swelling test.The temporal dependency of swelling is characterized by the viscosity coefficient of water absorption in a proposed swelling model.Results indicate that the swelling deformation of red-bed rocks is due to a combination of hydration swelling within the rock matrix and crack expansion caused by air breakage.In the unconfined swelling test,the final axial swelling strain of red-bed rocks decreases linearly with increasing slake index,while the viscosity coefficient increases exponentially with the slake index.In the oedometric swelling test,red-bed rocks with lower slake durability show greater sensitivity to lateral constraint and overburden load compared to those with higher slake durability. 展开更多
关键词 Rock swelling Slake durability Time effect Unconfined swelling test Oedometric swelling test
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Impact of typical environments in China’s western mountainous areas on the durability of railway concrete:a review
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作者 Jiahe Wang Yanbin Tan +3 位作者 Huajian Li Xinhua Zhong Jiaxuan Wang Yu Gao China 《Railway Sciences》 2024年第5期650-669,共20页
Purpose–This study aims to analyze the impact mechanism of typical environments in China’s western mountainous areas on the durability of railway concrete and propose measures to improve durability.Design/methodolog... Purpose–This study aims to analyze the impact mechanism of typical environments in China’s western mountainous areas on the durability of railway concrete and propose measures to improve durability.Design/methodology/approach–With the continuous promotion of infrastructure construction,the focus of China’s railway construction has gradually shifted to the western region.The four typical environments of large temperature differences,strong winds and dryness,high cold and low air pressure unique to the western mountainous areas of China have adverse effects on the durability of typical railway structure concrete(bridges,ballastless tracks and tunnels).This study identified the characteristics of four typical environments in the western mountainous areas of China through on-site research.The impact mechanism of the four typical environments on the durability of concrete in different structural parts of railways has been explored through theoretical analysis and experimental research;Finally,a strategy for improving the durability of railway concrete suitable for the western mountainous areas of China was proposed.Findings–The daily temperature difference in the western mountainous areas of China is more than twice that of the plain region,which will lead to significant temperature deformation and stress in the multi-layered structure of railway ballastless tracks.It will result in cracking.The wind speed in the western plateau region is about 2.5 to 3 times that of the plain region,and the average annual rainfall is only 1/5 of that in the plain region.The drying effect on the surface of casting concrete will significantly accelerate its cracking process,leading to serious durability problems.The environmental temperature in the western mountainous areas of China is generally low,and there are more freeze-thaw cycles,which will increase the risk of freeze-thaw damage to railway concrete.The environmental air pressure in the western plateau region is only 60%of that in the plain region.The moisture inside the concrete is more likely to diffuse into the surrounding environment under the pressure difference,resulting in greater water loss and shrinkage deformation of the concrete in the plateau region.The above four issues will collectively lead to the rapid deterioration of concrete durability in the western plateau region.The corresponding durability improvement suggestions from theoretical research,new technology development and standard system was proposed in this paper.Originality/value–The research can provide the mechanism of durability degradation of railway concrete in the western mountainous areas of China and corresponding improvement strategies. 展开更多
关键词 Western mountainous areas CONCRETE durability ENVIRONMENT
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Durability evaluation for existing railway engineering: a review
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作者 Jiahe Wang Huajian Li +3 位作者 Chengxian Ma Chaoxun Cai Zhonglai Yi Jiaxuan Wang 《Railway Sciences》 2024年第1期59-68,共10页
Purpose – This study aims to analyze the factors, evaluation techniques of the durability of existing railwayengineering.Design/methodology/approach – China has built a railway network of over 150,000 km. Ensuring t... Purpose – This study aims to analyze the factors, evaluation techniques of the durability of existing railwayengineering.Design/methodology/approach – China has built a railway network of over 150,000 km. Ensuring thesafety of the existing railway engineering is of great significance for maintaining normal railway operationorder. However, railway engineering is a strip structure that crosses multiple complex environments. Andrailway engineering will withstand high-frequency impact loads from trains. The above factors have led todifferences in the deterioration characteristics and maintenance strategies of railway engineering compared toconventional concrete structures. Therefore, it is very important to analyze the key factors that affect thedurability of railway structures and propose technologies for durability evaluation.Findings – The factors that affect the durability and reliability of railway engineering are mainly divided intothree categories: material factors, environmental factors and load factors. Among them, material factors alsoinclude influencing factors, such as raw materials, mix proportions and so on. Environmental factors varydepending on the service environment of railway engineering, and the durability and deterioration of concretehave different failure mechanisms. Load factors include static load and train dynamic load. The on-site rapiddetection methods for five common diseases in railway engineering are also proposed in this paper. Thesemethods can quickly evaluate the durability of existing railway engineering concrete.Originality/value – The research can provide some new evaluation techniques and methods for thedurability of existing railway engineering. 展开更多
关键词 durability assessment Existing railway engineering Evaluation techniques
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Influence of railway wheel tread damage on wheel-rail impact loads and the durability of wheelsets
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作者 Michele Maglio Tore Vernersson +2 位作者 Jens C.O.Nielsen Anders Ekberg Elena Kabo 《Railway Engineering Science》 EI 2024年第1期20-35,共16页
Dynamic wheel-rail contact forces induced by a severe form of wheel tread damage have been measured by a wheel impact load detector during full-scale field tests at different vehicle speeds.Based on laser scanning,the... Dynamic wheel-rail contact forces induced by a severe form of wheel tread damage have been measured by a wheel impact load detector during full-scale field tests at different vehicle speeds.Based on laser scanning,the measured three-dimensional damage geometry is employed in simulations of dynamic vehicle-track interaction to calibrate and verify a simulation model.The relation between the magnitude of the impact load and various operational parameters,such as vehicle speed,lateral position of wheel-rail contact,track stiffness and position of impact within a sleeper bay,is investigated.The calibrated model is later employed in simulations featuring other forms of tread damage;their effects on impact load and subsequent fatigue impact on bearings,wheel webs and subsurface initiated rolling contact fatigue of the wheel tread are assessed.The results quantify the effects of wheel tread defects and are valuable in a shift towards condition-based maintenance of running gear,and for general assessment of the severity of different types of railway wheel tread damage. 展开更多
关键词 Wheel tread damage Rolling contact fatigue cluster Field measurements Dynamic vehicle-track interaction Wheel-rail impact load Wheelset durability
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Preparation of Durable Antibacterial Polyester Fabrics by Grafting with the Natural Quaternary Ammonium Compound Betaine
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作者 Md Shariful Islam Md Kamrul Hasan +3 位作者 Arifur Rahman Shakhauat Hossen Md Anwarul Islam Sachi Xinbo Ding 《Materials Sciences and Applications》 2024年第9期378-398,共21页
Recently, the textile industry has increasingly advocated for natural resource-based healthcare textiles. This research presents a facile and eco-friendly approach to developing durable antibacterial polyester fabrics... Recently, the textile industry has increasingly advocated for natural resource-based healthcare textiles. This research presents a facile and eco-friendly approach to developing durable antibacterial polyester fabrics. Polyester fabric was first subjected to an alkaline hydrolysis to impart hydroxyl groups on the fiber surface. A natural antibacterial agent, betaine, was then covalently bonded to the hydrolyzed polyester fiber surface through esterification. XPS, Raman, SEM, and Wicking measurements were carried out to verify the esterification reaction. Antibacterial tests confirmed that betaine treatment grafted polyester fabrics revealed a remarkable antibacterial effect with inhibition rates > 99.9% against both E. coli and S. aureus and still remained inhibition rates of up to 91.5% against both bacteria after home washing for 20 cycles. Moreover, the modification significantly increased the capillary effect of polyester fabric but did not cause apparent adverse effects on the fabric’s hand or tensile strength. Overall, this grafting strategy for durable, antibacterial polyester fabric represents a significant practicality in the textile industry. 展开更多
关键词 Polyester Fabric BETAINE ANTIBACTERIAL durability CAPILLARY
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Dry Mix Slag—High-Calcium Fly Ash Binder. Part Two: Durability
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作者 Alexey Brykov Mikhail Voronkov 《Materials Sciences and Applications》 2024年第3期37-51,共15页
This work investigates durability of cement-free mortars with a binder comprised of ground granulated blast furnace slag (GGBFS) activated by high-calcium fly ash (HCFA) and sodium carbonate (Na<sub>2</sub>... This work investigates durability of cement-free mortars with a binder comprised of ground granulated blast furnace slag (GGBFS) activated by high-calcium fly ash (HCFA) and sodium carbonate (Na<sub>2</sub>CO<sub>3</sub>): the soundness, sulfate resistance, alkali-silica reactivity and efflorescence factors are considered. Results of tests show that such mortars are resistant to alkali-silica expansion. Mortars are also sulfate-resistant when the amount of HCFA in the complex binder is within a limit of 10 wt%. The fineness of fly ash determines its’ ability to activate GGBFS hydration, and influence soundness of the binder, early strength development, sulfate resistance and efflorescence behavior. The present article is a continuation of authors’ work, previously published in MSA, Vol. 14, 240-254. 展开更多
关键词 Ground Granulated Blast-Furnace Slag High-Calcium Fly-Ash Sodium Car-bonate Blast-Furnace Slag Binder durability ASR Sulfate Attack SOUNDNESS EFFLORESCENCE
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Study on Durability of Recycled Aggregate Concrete in High-Temperature and Complex Environments
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作者 Xiaoqing Hu Yao Tong +1 位作者 Xuan Min Rongchong Xu 《Journal of World Architecture》 2024年第5期66-71,共6页
Recycled aggregate concrete refers to a new type of concrete material made by processing waste concrete materials through grading,crushing,and cleaning,and then mixing them with cement,water,and other materials in a c... Recycled aggregate concrete refers to a new type of concrete material made by processing waste concrete materials through grading,crushing,and cleaning,and then mixing them with cement,water,and other materials in a certain gradation or proportion.This type of concrete is highly suitable for modern construction waste disposal and reuse and has been widely used in various construction projects.It can also be used as an environmentally friendly permeable brick material to promote the development of modern green buildings.However,practical applications have found that compared to ordinary concrete,the durability of this type of concrete is more susceptible to high-temperature and complex environments.Based on this,this paper conducts theoretical research on its durability in high-temperature and complex environments,including the current research status,existing problems,and application prospects of recycled aggregate concrete’s durability in such environments.It is hoped that this analysis can provide some reference for studying the influence of high-temperature and complex environments on recycled aggregate concrete and its subsequent application strategies. 展开更多
关键词 Recycled aggregate concrete Construction engineering High-temperature and complex environment durability
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