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Chlorfenapyr poisoning:mechanisms,clinical presentations,and treatment strategies
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作者 Ji Cheng Yulu Chen +4 位作者 Weidong Wang Xueqi Zhu Zhenluo Jiang Peng Liu Liwen Du 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第3期214-219,共6页
BACKGROUND:Chlorfenapyr is used to kill insects that are resistant to organophosphorus insecticides.Chlorfenapyr poisoning has a high mortality rate and is difficult to treat.This article aims to review the mechanisms... BACKGROUND:Chlorfenapyr is used to kill insects that are resistant to organophosphorus insecticides.Chlorfenapyr poisoning has a high mortality rate and is difficult to treat.This article aims to review the mechanisms,clinical presentations,and treatment strategies for chlorfenapyr poisoning.DATA RESOURCES:We conducted a review of the literature using PubMed,Web of Science,and SpringerLink from their beginnings to the end of October 2023.The inclusion criteria were systematic reviews,clinical guidelines,retrospective studies,and case reports on chlorfenapyr poisoning that focused on its mechanisms,clinical presentations,and treatment strategies.The references in the included studies were also examined to identify additional sources.RESULTS:We included 57 studies in this review.Chlorfenapyr can be degraded into tralopyril,which is more toxic and reduces energy production by inhibiting the conversion of adenosine diphosphate to adenosine triphosphate.High fever and altered mental status are characteristic clinical presentations of chlorfenapyr poisoning.Once it occurs,respiratory failure occurs immediately,ultimately leading to cardiac arrest and death.Chlorfenapyr poisoning is diflcult to treat,and there is no specific antidote.CONCLUSION:Chlorfenapyr is a new pyrrole pesticide.Although it has been identified as a moderately toxic pesticide by the World Health Organization(WHO),the mortality rate of poisoned patients is extremely high.There is no specific antidote for chlorfenapyr poisoning.Therefore,based on the literature review,future efforts to explore rapid and effective detoxification methods,reconstitute intracellular oxidative phosphorylation couplings,identify early biomarkers of chlorfenapyr poisoning,and block the conversion of chlorfenapyr to tralopyril may be helpful for emergency physicians in the diagnosis and treatment of this disease. 展开更多
关键词 Chlorfenapyr poisoning mechanism Clinical presentation treatment
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Drug resistance mechanisms in cancers:Execution of prosurvival strategies
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作者 Pavan Kumar Dhanyamraju 《Journal of Biomedical Research》 CAS CSCD 2024年第2期95-121,共27页
One of the quintessential challenges in cancer treatment is drug resistance.Several mechanisms of drug resistance have been described to date,and new modes of drug resistance continue to be discovered.The phenomenon o... One of the quintessential challenges in cancer treatment is drug resistance.Several mechanisms of drug resistance have been described to date,and new modes of drug resistance continue to be discovered.The phenomenon of cancer drug resistance is now widespread,with approximately 90% of cancer-related deaths associated with drug resistance.Despite significant advances in the drug discovery process,the emergence of innate and acquired mechanisms of drug resistance has impeded the progress in cancer therapy.Therefore,understanding the mechanisms of drug resistance and the various pathways involved is integral to treatment modalities.In the present review,I discuss the different mechanisms of drug resistance in cancer cells,including DNA damage repair,epithelial to mesenchymal transition,inhibition of cell death,alteration of drug targets,inactivation of drugs,deregulation of cellular energetics,immune evasion,tumor-promoting inflammation,genome instability,and other contributing epigenetic factors.Furthermore,I highlight available treatment options and conclude with future directions. 展开更多
关键词 cancer drug resistance mechanismS MICRORNAS treatment strategies
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Microstructure and mechanical properties of Co-28Cr-6Mo-0.22C investment castings by current solution treatment
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作者 Ze-yu Dan Jun Liu +4 位作者 Jian-lei Zhang Yan-hua Li Yuan-xin Deng Yun-hu Zhang Chang-jiang Song 《China Foundry》 SCIE EI CAS CSCD 2024年第4期369-378,共10页
This study examined the impact of current solution treatment on the microstructure and mechanical properties of the Co-28Cr-6Mo-0.22C alloy investment castings.The findings reveal that the current solution treatment s... This study examined the impact of current solution treatment on the microstructure and mechanical properties of the Co-28Cr-6Mo-0.22C alloy investment castings.The findings reveal that the current solution treatment significantly promotes the dissolution of carbides at a lower temperature.The optimal conditions for solution treatment are determined as a solution temperature of 1,125°C and a holding time of 5.0 min.Under these parameters,the size and volume fraction of precipitated phases in the investment castings are measured as6.2μm and 1.1vol.%.The yield strength,ultimate tensile strength,and total elongation of the Co-28Cr-6Mo-0.22C investment castings are 535 MPa,760 MPa,and 12.6%,respectively.These values exceed those obtained with the conventional solution treatment at 1,200°C for 4.0 h.The findings suggest a phase transformation of M_(23)C_(6)→σ+C following the current solution treatment at 1,125°C for 5.0 min.In comparison,the traditional solution treatment at 1,200°C for 4.0 h leads to the formation of M_(23)C_(6)and M_(6)C carbides.It is noteworthy that the non-thermal effect of the current during the solution treatment modifies the free energy of both the matrix and precipitation phase.This modification lowers the phase transition temperature of the M_(23)C_(6)→σ+C reaction,thereby facilitating the dissolution of carbides.As a result,the current solution treatment approach achieves carbide dissolution at a lower temperature and within a significantly shorter time when compared to the traditional solution treatment methods. 展开更多
关键词 CoCrMo alloy investment castings current solution treatment microstructure mechanical property CARBIDE
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Influence of heat treatment on microstructure,mechanical and corrosion behavior of WE43 alloy fabricated by laser-beam powder bed fusion
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作者 Chenrong Ling Qiang Li +6 位作者 Zhe Zhang Youwen Yang Wenhao Zhou Wenlong Chen Zhi Dong Chunrong Pan Cijun Shuai 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第1期258-275,共18页
Magnesium(Mg)alloys are considered to be a new generation of revolutionary medical metals.Laser-beam powder bed fusion(PBF-LB)is suitable for fabricating metal implants withpersonalized and complicated structures.Howe... Magnesium(Mg)alloys are considered to be a new generation of revolutionary medical metals.Laser-beam powder bed fusion(PBF-LB)is suitable for fabricating metal implants withpersonalized and complicated structures.However,the as-built part usually exhibits undesirable microstructure and unsatisfactory performance.In this work,WE43 parts were firstly fabricated by PBF-LB and then subjected to heat treatment.Although a high densification rate of 99.91%was achieved using suitable processes,the as-built parts exhibited anisotropic and layeredmicrostructure with heterogeneously precipitated Nd-rich intermetallic.After heat treatment,fine and nano-scaled Mg24Y5particles were precipitated.Meanwhile,theα-Mg grainsunderwent recrystallization and turned coarsened slightly,which effectively weakened thetexture intensity and reduced the anisotropy.As a consequence,the yield strength and ultimate tensile strength were significantly improved to(250.2±3.5)MPa and(312±3.7)MPa,respectively,while the elongation was still maintained at a high level of 15.2%.Furthermore,the homogenized microstructure reduced the tendency of localized corrosion and favoredthe development of uniform passivation film.Thus,the degradation rate of WE43 parts was decreased by an order of magnitude.Besides,in-vitro cell experiments proved their favorable biocompatibility. 展开更多
关键词 laser-beam powder bed fusion WE43 alloys heat treatment mechanical performance biodegradation behavior
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Effect of Heat Treatment on Microstructure and Mechanical Properties of Multiscale SiC_p Hybrid Reinforced 6061 Aluminum Matrix Composites
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作者 吴健铭 许晓静 +3 位作者 ZHANG Xu LUO Yuntian LI Shuaidi HUANG Lin 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期174-181,共8页
The performance of solid solution aging treatment on aluminum matrix composites prepared by powder metallurgy and reinforced with 6061 aluminum alloy powder as matrix;meanwhile, nano silicon carbide particles(nm Si Cp... The performance of solid solution aging treatment on aluminum matrix composites prepared by powder metallurgy and reinforced with 6061 aluminum alloy powder as matrix;meanwhile, nano silicon carbide particles(nm Si Cp), submicron silicon carbide particles(1 μm Si Cp) and Ti particles were studied. The Al/Si Cp composite powder was prepared by high-energy ball milling, and then cold-pressed, sintered, hotextruded, and then heat-treated with different solution temperatures and aging times for the extruded composites. Optical microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy(EDS), X-ray diffractometer(XRD) and extrusion testing were used to analyze and test the microstructure and mechanical properties of aluminum matrix composites. The results show that after the multi-stage solid solution at 530 ℃×2 h+535 ℃×2 h+540 ℃×2 h, the particles are mainly equiaxed grains and uniformly distributed. There is no reinforcement agglomeration, and the surface is dense and the insoluble phase is basically dissolved. In the matrix, the strengthening effect is good, and the hardness and compressive strength are 179.43 HV and 680.42 MPa, respectively. Under this solution process, when the aluminum matrix composites are aged at 170 ℃ for 10 h, the hardness and compressive strength can reach their peaks and increase to 195.82 HV and 721.48 MPa, respectively. 展开更多
关键词 aluminum matrix composites Si C particles multiscale hybrid enhancement heat treatment mechanical properties
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Numerical and experimental analyses of rock failure mechanisms due to microwave treatment
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作者 Haitham M.Ahmed Adel Ahmadihosseini +5 位作者 Ferri Hassani Mohammed A.Hefni HussinA.M.Ahmed Hussein A.Saleem Essam B.Moustafa Agus P.Sasmito 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第10期2483-2495,共13页
Despite the extensive studies conducted on the effectiveness of microwave treatment as a novel rock preconditioning method,there is yet to find reliable data on the rock failure mechanisms due to microwave heating.In ... Despite the extensive studies conducted on the effectiveness of microwave treatment as a novel rock preconditioning method,there is yet to find reliable data on the rock failure mechanisms due to microwave heating.In addition,there is no significant discussion on the energy efficiency of the method as one of the important factors among the mining and geotechnical engineers in the industry.This study presents a novel experimental method to evaluate two main rock failure mechanisms due to microwave treatment without applying any mechanical forces,i.e.distributed and concentrated heating.The result shows that the existence of a small and concentrated fraction of a strong microwave absorbing mineral will change the failure mechanism from the distributed heating to the concentrated heating,which can increase the weakening over microwave efficiency(WOME)by more than 10 folds.This observation is further investigated using the developed coupled numerical model.It is shown that at the same input energy,the existence of microwave absorbing minerals can cause major heat concentration inside the rock and increase the maximum temperature by up to three times. 展开更多
关键词 Microwave treatment Numerical modeling Failure mechanism Energy efficiency Rock pre-conditioning
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Deformation Mechanism of Bimodal Structured 2205 Duplex Stainless Steel in Two Yield Stages
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作者 盛捷 DU Mingchen +7 位作者 LI Yufeng MA Guocai CHEN Weiqian ZHENG Yuehong ZHAN Faqi REN Junqiang G I Raab 喇培清 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第1期184-191,共8页
A kind of micro/nanostructured 2205 duplex stainless steel(DSS)with uniform distribution of nanocrystals was prepared via aluminothermic reaction method.The analysis of stress-strain curve showed that the fracture str... A kind of micro/nanostructured 2205 duplex stainless steel(DSS)with uniform distribution of nanocrystals was prepared via aluminothermic reaction method.The analysis of stress-strain curve showed that the fracture strength and elongation of the specimen were 946 MPa and 24.7%,respectively.At present,the research on microstructure of bimodal 2205 DSS at room temperature(RT)mainly depended on scanning electron microscope(SEM)observation after loading experiments.The test result indicates that there are two different yield stages in stress-strain curve of specimen during tensile process.The microstructure of duplex bimodal structured stainless steel consists of two pairs of soft hard regions and phases.By studying deformation mechanism of bimodal structured stainless steel,the interaction between soft phase and hard phase are discussed.The principle of composition design and microstructure control of typical duplex stainless steel is obtained,which provides an important research basis for designing of advanced duplex stainless steel. 展开更多
关键词 2205 duplex stainless steel bimodal structure in-situ tensile test deformation mechanism two different yield stages
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3D inner-outer asymmetric sponge for enormous-volume emulsion wastewater treatment based on a new“demulsification-transport”mechanism
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作者 Ruixiang Qu Shuaiheng Zhao +5 位作者 Na Liu Xiangyu Li Huajun Zhai Ya'nan Liu Yen Wei Lin Feng 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第5期1398-1408,共11页
Although oily wastewater treatment realized by superwetting materials has attracted heightened attention in recent years,how to treat enormous-volume emulsion wastewater is still a tough problem,which is ascribed to t... Although oily wastewater treatment realized by superwetting materials has attracted heightened attention in recent years,how to treat enormous-volume emulsion wastewater is still a tough problem,which is ascribed to the emulsion accumulation.Herein,to address this problem,a material is presented by subtly integrating chemical demulsification and 3D inner-outer asymmetric wettability to a sponge substrate,and thus wettability gradient-driven oil directional transport for achieving unprecedented enormous-volume emulsion wastewater treatment is realized based on a“demulsification-transport”mechanism.The maximum treatment volume realized by the sponge is as large as 3 L(2.08×10^(4) L per cubic meter of the sponge)in one cycle,which is about 100 times of the reported materials.Besides,owing to the large pore size of the sponge,9000 L m^(2)h^(-1)(LMH)separation flux and 99.5%separation efficiency are realized simultaneously,which overcomes the trade-off dilemma.Such a 3D inner-outer asymmetric sponge displaying unprecedented advantage in the treatment volume can promote the development of the oily wastewater treatment field,as well as expand the application prospects of superwetting materials,especially in continuous water treatment. 展开更多
关键词 Enormous-volume emulsion treatment Inner-outer asymmetric wettability Demulsification-transport mechanism High separation efficiency
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The mechanism of TCM prevention and treatment of heavy COVID-19 based on data mining and network pharmacology
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作者 Zi-Tong Fu Jia-Yu Wang +2 位作者 Yi Liu Jia-Ming Xiong Guo-Wei Zhang 《Drug Combination Therapy》 2023年第2期30-39,共10页
Objective:Using big data mining technology and network pharmacology,this study aimed to identify the dominant traditional Chinese medicine(TCM)for the prophylaxis and treatment of severe Corona Virus Disease 2019(COVI... Objective:Using big data mining technology and network pharmacology,this study aimed to identify the dominant traditional Chinese medicine(TCM)for the prophylaxis and treatment of severe Corona Virus Disease 2019(COVID-19),predict the pharmacological mechanism of the dominant anti-epidemic TCM,and provide clinical guidance for COVID-19 prevention and control.Methods:The Traditional Chinese Medicine Inheritance Computing Platform V3.0 was utilized to identify the high-frequency TCM in the adult severe prescriptions of the national Diagnosis and Treatment Plan for COVID-19(Trial 10th edition)and the TCM prophylaxis and cure plan for COVID-19 in 27 regions.The active ingredients and potential targets of the high-frequency core drugs were analyzed using Traditional Chinese Medicine Systems Pharmacology Technology Platform,Traditional Chinese Medicine Integrated Database,and Traditional Chinese Medicine Encyclopedia Database,and the network of“core drug active ingredient-potential targets”was obtained.The String platform was used to establish the protein-protein interaction structure chart,and Cytoscape software was used for visualization and network topology analysis to identify pivotal targets.Signal pathway enrichment analysis of the core targets was performed,and the affinity of the active components entering the blood was predicted by docking with the related targets of the novel coronavirus.Results:Ellagic acid,Vestitol,naringin,dehydroglyasperins C,quercetin,and kaemol were identified as 67 active constituents in the blood.After docking the active constituents with angiotensin-converting enzyme II,3C-likeProteinase,and tyrosine protein kinase receptor UFO,they all showed good affinity.The pivotal targets mainly involved inflammatory factors such as IL-6 and TNF.Pathway concentration analysis of gene ontology and Kyoto Encyclopedia of Genes and Genomes pathways focused on inflammatory and immune-related pathways such as the TNF signaling pathway.Conclusion:The high-frequency core drugs may act on the body through active components such as ellagic acid,Vestitol,naringin,dehydroglyasperins C,quercetin,and kaemol.Inflammatory and related immune pathways,such as the TNF signaling pathway,may suppress cytokine storms and effectively treat patients with severe COVID-19. 展开更多
关键词 diagnosis and treatment scheme novel coronavirus molecular docking mechanism of action
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Newborn with Giant Non-Involuting Congenital Hemangioma: Mechanisms of Allodynia, Hyperalgesia and Treatment
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作者 Valeria Bachiocco Ilenia Casini Andrea Gentili 《Case Reports in Clinical Medicine》 2023年第10期397-407,共11页
In a newborn affected by a non involuting congenital hemangioma we measured allodynia through the application of a standard tactile stimulus and hyperalgesia through the regular administration of the Comfort scale whi... In a newborn affected by a non involuting congenital hemangioma we measured allodynia through the application of a standard tactile stimulus and hyperalgesia through the regular administration of the Comfort scale which rates pain intensity. The baby presented signs of these pathological events over long periods of the disease. They may be attributed to the high amount of the nociceptive ligands in the hemangioma microenviroment and to the elevated concentration of TNF-alpha and IL-6 in the blood. For a long time, the pain was relieved by a combination of opioids, adjuvants and paracetamol, but also by thalidomide and unexpectedly by interferon alpha. A mechanism-based pain treatment needs to take into account the processes underlying pain and also the ongoing pathology. 展开更多
关键词 Pain mechanisms ALLODYNIA HYPERALGESIA NEWBORN treatment
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Traditional Chinese medicine for the treatment of endometriosis: a comprehensive-review of treatment mechanisms
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作者 Chong Feng Da Zhao +1 位作者 Xiao-Li Wang Man Xiao 《TMR Modern Herbal Medicine》 2023年第2期40-48,共9页
The study aims to reveal the mechanism of traditional Chinese medicine in the treatment of endometriosis and provide support for further research on traditional Chinese medicine and its active ingredients.The literatu... The study aims to reveal the mechanism of traditional Chinese medicine in the treatment of endometriosis and provide support for further research on traditional Chinese medicine and its active ingredients.The literature survey was conducted using PubMed,Web of Science,CNKI and other databases with“endometriosis”,“Chinese medicine”,“Chinese herbal medicine”and“natural plants”as the main keywords.Traditional Chinese medicine can exert their therapeutic effects on endometriosis by inhibiting inflammation through multiple pathways and multiple targets,regulating cell proliferation and apoptosis,angiogenesis,cell adhesion and oxidative stress.Traditional Chinese medicine can intervene in endometriosis in multiple ways and with multiple targets.In-depth study of Chinese medicine for endometriosis can provide new ideas for exploring the pathogenesis of endometriosis and developing new drugs. 展开更多
关键词 traditional Chinese medicine ENDOMETRIOSIS treatment mechanism
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The mechanism and relevant mediators associated with neuronal apoptosis and potential therapeutic targets in subarachnoid hemorrhage 被引量:3
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作者 Qi Tian Sheng Liu +6 位作者 Shou-Meng Han Wei Zhang Xian-Yao Qin Jun-Hui Chen Cheng-Li Liu Yu-Jia Guo Ming-Chang Li 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第2期244-252,共9页
Subarachnoid hemorrhage(SAH)is a dominant cause of death and disability wo rldwide.A sharp increase in intracranial pressure after SAH leads to a reduction in cerebral perfusion and insufficient blood supply for neuro... Subarachnoid hemorrhage(SAH)is a dominant cause of death and disability wo rldwide.A sharp increase in intracranial pressure after SAH leads to a reduction in cerebral perfusion and insufficient blood supply for neuro ns,which subsequently promotes a series of pathophysiological responses leading to neuronal death.Many previous experimental studies have reported that excitotoxicity,mitochondrial death pathways,the release of free radicals,protein misfolding,apoptosis,nec rosis,autophagy,and inflammation are involved solely or in combination in this disorder.Among them,irreversible neuronal apoptosis plays a key role in both short-and long-term prognoses after SAH.Neuronal apoptosis occurs through multiple pathways including extrinsic,mitochondrial,endoplasmic reticulum,p53 and oxidative stress.Meanwhile,a large number of blood contents enter the subarachnoid space after SAH,and the secondary metabolites,including oxygenated hemoglo bin and heme,further aggravate the destruction of the blood-brain barrier and vasogenic and cytotoxic brain edema,causing early brain injury and delayed cerebral ischemia,and ultimately increasing neuronal apoptosis.Even there is no clear and effective therapeutic strategy for SAH thus far,but by understanding apoptosis,we might excavate new ideas and approaches,as targeting the upstream and downstream molecules of apoptosis-related pathways shows promise in the treatment of SAH.In this review,we summarize the existing evidence on molecules and related drugs or molecules involved in the apoptotic pathway after SAH,which provides a possible target or new strategy for the treatment of SAH. 展开更多
关键词 blood-brain barrier mechanism MEDIATORS neuronal apoptosis PATHWAYS subarachnoid hemorrhage TARGETS treatment
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Effect of heat treatment on the microstructure and mechanical properties of a multidirectionally forged Mg-Gd-Y-Zn-Zr-Ag alloy 被引量:2
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作者 Junkai Wang Chuming Liu +2 位作者 Shunong Jiang Yingchun Wan Zhiyong Chen 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第6期2042-2053,共12页
Multidirectional forging(MDF)was successfully applied to fabricate large-size Mg-Gd-Y-Zn-Zr-Ag alloy in this work and effects of T4,T5 and T6 treatments on the microstructure and mechanical properties of the as-forged... Multidirectional forging(MDF)was successfully applied to fabricate large-size Mg-Gd-Y-Zn-Zr-Ag alloy in this work and effects of T4,T5 and T6 treatments on the microstructure and mechanical properties of the as-forged alloy were analyzed.Results show that dynamic recrystallization(DRX)occurs and second phase particles precipitate along the grain boundary during the MDF process.After annealing treatment(T4),the volume fraction and size of dynamic precipitates slightly increase at a lower temperature(430℃)compared with those of MDFed sample,while they are dissolved into theα-Mg matrix at a higher temperature(450℃).At the meantime,short plate-shaped long-period stacking ordered(LPSO)phases are observed in the DRX grains of the MDFed sample and then dissolved into theα-Mg matrix during annealing at both temperatures.Typical basal texture is identified in the MDFed sample,but the basal pole tilts away from final forging direction and rare-earth texture component with<1121>orientation parallel to penultimate forging direction becomes visible after annealing.The T6 sample annealing at 430℃for 4 h and ageing at 200℃for 34 h exhibits the superior strength and ductility in this study.The ultimate tensile strength,tensile yield strength and elongation to failure,which is 455 MPa,308 MPa and 7.7%,respectively,are overall improved compared with the directly-aged(T5)sample.This paper provides a superior heat treatment schedule to manufacture high-performance large-scale Mg-Gd-Y-Zn-Zr-Ag components for industrial production. 展开更多
关键词 Mg-Gd-Y-Zn-Zr-Ag alloy Multidirectional forging Dynamic precipitation Heat treatment mechanical properties
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Effect of heat treatment on microstructure,mechanical and tribological properties of in-situ (TiC+TiB)/TC4 composites by casting 被引量:1
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作者 Bo-wen Zheng Shuai Chen +6 位作者 Chun-yu Yue Xue-jian Lin Fu-yu Dong Hong-jun Huang Xiao-jiao Zuo Yin-xiao Wang Xiao-guang Yuan 《China Foundry》 SCIE CAS CSCD 2023年第3期207-217,共11页
To enhance the performance of in-situ synthesized 6vol.%(Ti C+Ti B)/TC4 titanium matrix composites fabricated by casting,a variety of heat treatment processes were carried out.Upon conducting microstructure observatio... To enhance the performance of in-situ synthesized 6vol.%(Ti C+Ti B)/TC4 titanium matrix composites fabricated by casting,a variety of heat treatment processes were carried out.Upon conducting microstructure observations following various heat treatments,it was found that the composites exhibit a basketweave microstructure,consisting of an α phase and a transformed β phase.The sizes of(α+β) phases were found to be refined to varying degrees after the heat treatment processes,while the morphology of Ti B remains largely unchanged and Ti C becomes granulated.Compressive testing revealed that all composites subjected to different heat treatments demonstrate a notable increase in ultimate compressive strength as well as a slight improvement in plasticity compared to the as-cast state.The results of the tribological performance test indicated that the heat-treated composites exhibit lower average friction coefficient,specific wear rate,and worn surface roughness compared to the as-cast composite.Among the heat treatment processes studied,the composite solution heated at 1,150 °C/1 h followed by air cooling,then 950 °C/1 h followed by air cooling,and finally 500 °C/4 h followed by air cooling,demonstrates the highest levels of hardness,compressive strength,and wear resistance.These improvements are attributed to the combined effects of solid solution strengthening,grain refinement,and the pinning of dislocation slip. 展开更多
关键词 titanium matrix composites heat treatment mechanical properties tribological properties
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Effect of deep cryogenic treatment on the microstructural,mechanical and ballistic properties of AA7075-T6 aluminum alloy 被引量:1
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作者 S.Dharani kumar U.Magarajan +1 位作者 Saurabh S Kumar Rodríguez-Millan M 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第12期101-110,共10页
The study focused on investigating the effect of Deep Cryogenic Treatment(DCT)on the mechanical and ballistic properties of AA7075-T6 aluminum alloy.The microstructure,microhardness,tensile strength,and impact strengt... The study focused on investigating the effect of Deep Cryogenic Treatment(DCT)on the mechanical and ballistic properties of AA7075-T6 aluminum alloy.The microstructure,microhardness,tensile strength,and impact strength of the Base Material(BM)and DCT-treated 7075 samples were analyzed through metallographic analysis and mechanical tests.The microstructure of the DCT-treated 7075 samples revealed fine grains and a distribution of secondary phase particles.The tensile strength,impact strength,and microhardness of DCT-treated samples increased by 7.41%,4%,and 9.68%,respectively,compared to the BM samples.The fractography analysis of the tensile samples showed cleavage facets,microvoids,and dimples in both the samples.The ballistic behavior of the BM and DCT target plates were studied by impacting hard steel core projectiles at a velocity of 750±10 m/s.The target plates failed due to petaling and ductile hole enlargement,and the depth of penetration(DOP)of the DCT target was less than that of the BM target,indicating a higher ballistic resistance.The post-ballistic microstructure examination of the target plates showed the formation of an Adiabatic Shear Band(ASB)without any cracks.It was concluded that the DCT treatment improved the mechanical and ballistic properties of the aluminum alloy due to grain refinement and high dislocation density. 展开更多
关键词 Deep cryogenic treatment AA7075-T6 mechanical properties BALLISTIC Adiabatic shear band
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Insights of priapism mechanism and rationale treatment for recurrent priapism 被引量:6
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作者 Jiuhong Yuan Rowena DeSouza O. Lenaine Westney Run Wang 《Asian Journal of Andrology》 SCIE CAS CSCD 2008年第1期88-101,共14页
Priapism is defined as abnormal prolonged penile erection occurring beyond or unrelated to sexual interest. The disorder is enigmatic yet devastating because of its elusive etiology, irreversible erectile tissue damag... Priapism is defined as abnormal prolonged penile erection occurring beyond or unrelated to sexual interest. The disorder is enigmatic yet devastating because of its elusive etiology, irreversible erectile tissue damage, and resultant erectile dysfunction (ED). Current management strategies suffer from a poor understanding of the pathophysiology, especially at the molecular level. The traditional treatments are based more on empirical rather than evidence-based knowledge. The outcomes for restoration of normal erectile function are poor, especially for stuttering priapism. Therefore, it is critical to understand priapism from a molecular level, to formulate treatment strategies and to establish rational prevention strategies for high-risk populations, such as sickle cell disease (SCD) patients and cases of the stuttering variant. This review focuses on the recent advances at the molecular level in priapism and penile erection, and applies the recent knowledge to the treatment of stuttering priapism. 展开更多
关键词 PRIAPISM stuttering priapism molecular mechanism treatment
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The Mechanism of Carotenoid Degradation in Flue-Cured Tobacco and Changes in the Related Enzyme Activities at the Leaf-Drying Stage During the Bulk Curing Process 被引量:6
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作者 SONG Zhao-peng LI Tong-shuai +3 位作者 ZHANG Yong-gang CAO Hui-jing GONG Chang-rong ZHANG Wei-jian 《Agricultural Sciences in China》 CSCD 2010年第9期1381-1388,共8页
The mechanism of carotenoid degradation and the changes in the activities of related enzymes in flue-cured tobacco at the leaf-drying stage during the bulk-curing process were studied in order to provide theoretical b... The mechanism of carotenoid degradation and the changes in the activities of related enzymes in flue-cured tobacco at the leaf-drying stage during the bulk-curing process were studied in order to provide theoretical basis for optimization of curing technology. The effect of different rising speeds of temperature on the carotenoid degradation and the related enzymes activities at the color-fixing stage during the bulk curing process was studied by using the electric-heated fluecuring barn designed by Henan Agricultural University, China, based on curing technology with yellowing at low temperature and moderate humidity and leaf drying at moderate humidity. The results showed that the carotenoid degradation components (β-carotene, lutein, neoxanthin, and violaxthin) decreased gradually at the color-fixing stage during the bulk curing process. The carotenoid degradation components viz.,β-carotene, lutein, neoxanthin, and violaxthin at the slow heating curing (T1) were relatively higher than the rapid heating curing (T2) accounting for 10, 2, 32 and 32% respectively, but there were no differences among treatments (P〉 0.05). The effect of different conditions of curing on the activities of enzymes related to carotenoids degradation were significant. The lipoxygenase, phenylalanine ammonialyase, peroxidase, and polyphenol oxidase enzymes had a bidirectional effect on the quality of tobacco leaves and it was beneficial to form more premise matter of aroma based on the higher enzyme activities at the early leaf-drying stage. The slow heating could regulate the change in various enzymes' activities reasonably, making cell redox reaction to reach the dynamic balance and make the degradation of carotenoids adequately. Meanwhile, it could avoid the occurrence of browning reaction and provide foundation for improving the quality of tobacco and optimization of technology for bulk curing and further enhancing aroma. 展开更多
关键词 bulk curing leaf-drying stage carotenoids mechanism of degradation enzyme
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Characteristics and control mechanisms of coalbed permeability change in various gas production stages 被引量:5
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作者 Da-Zhen Tang Chun-Miao Deng +4 位作者 Yan-Jun Meng Zhi-Ping Li Hao Xu Shu Tao Song Li 《Petroleum Science》 SCIE CAS CSCD 2015年第4期684-691,共8页
According to dimensionless analysis of the coalbed methane (CBM) production data of Fanzhuang block in southern Qinshui basin, the dimensionless gas production rate is calculated to quantitatively divide the CBM wel... According to dimensionless analysis of the coalbed methane (CBM) production data of Fanzhuang block in southern Qinshui basin, the dimensionless gas production rate is calculated to quantitatively divide the CBM well production process into four stages, i.e., drai- nage stage, unstable gas production stage, stable gas pro- duction stage, and gas production decline stage. By the material balance method, the coal reservoir permeability change in different stages is quantitatively characterized. The characteristics and control mechanisms of change in coalbed permeability (CICP) during different production stages are concluded on five aspects, i.e., permeability trend variation, controlling mechanism, system energy, phase state compositions, and production performance. The study reveals that CICP is characterized by first decline, then recovery, and finally by increase and is controlled directly by effective stress and matrix shrinkage effects. Further, the duration and intensity of the matrix shrinkage effect are inherently controlled by adsorption and desorp- tion features. 展开更多
关键词 Production stage - Coalbed methane PERMEABILITY Dynamic change - Control mechanism
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Roles and molecular mechanisms of physical exercise in cancer prevention and treatment 被引量:5
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作者 Qiaoyun Wang Wenli Zhou 《Journal of Sport and Health Science》 SCIE 2021年第2期201-210,共10页
Exercise can enhance motivation to change lifestyle behaviors,improve aerobic fitness,improve physical function,control fatigue,and enhance quality of life.Studies have demonstrated the benefits to be gained from phys... Exercise can enhance motivation to change lifestyle behaviors,improve aerobic fitness,improve physical function,control fatigue,and enhance quality of life.Studies have demonstrated the benefits to be gained from physical exercise,highlighting the importance of popularizing the concept of physical exercise for individuals and making professional exercise-treatment programs available to patients with cancer.However,the correlation between physical exercise and carcinogenesis is easily overlooked,and exercise interventions are not routinely provided to patients with cancer,especially those with advanced cancer.In this article,we present a literature review of the effects of exercise on cancer development and progression and give recent evidence for the type of exercise best suited for different types of cancer and in different disease stages.Moreover,the molecular mechanisms about regulating metabolism and systemic immune function in cancer are summarized and discussed.In conclusion,physical exercise should be considered as an important intervention for preventing and treating cancer and its complications. 展开更多
关键词 Cancer development Cancer treatment Molecular mechanisms Physical exercis
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Influence of multi-stage heat treatment on the microstructure and mechanical properties of TC21 titanium alloy 被引量:5
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作者 Wei Long Song Zhang +1 位作者 Yi-long Liang Mei-gui Ou 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第2期296-304,共9页
Duplex-structured TC21 alloy samples were first solution-treated at a higher temperature in theα+βregion(940°C)with furnace cooling(FC),air cooling(AC),and water cooling(WC),followed by a second-stage solution ... Duplex-structured TC21 alloy samples were first solution-treated at a higher temperature in theα+βregion(940°C)with furnace cooling(FC),air cooling(AC),and water cooling(WC),followed by a second-stage solution treatment at a lower temperature in theα+βregion(900°C),and then finally aged at 590°C.The effects of the morphology and quantity ofαphases on the structure and properties of the TC21 alloy after the different heat treatments were analyzed.The in-situ tensile deformation process and crack propagation behavior were observed using scanning electron microscopy(SEM).The quantity of equiaxedαphases as well as the thickness of lamellarαphases reduced,the tensile strength increased firstly and then decreased,the elongation decreased with the increasing cooling rate after the first-stage solution treatment.The amount and size of lamellarαphases increased after the second-stage solution treatment because of sufficient diffusion of the alloying elements,thereby leading to increased tensile strength.The amount of dispersedαphases increased after the third-stage aging treatment owing to the increase in the nucleation rate,resulting in a noteworthy strengthening effect.After the third-stage aging treatment,the first-stage FC sample exhibited better mechanical properties because it contained more equiaxedαandβtrans phases than the first-stage AC and WC samples. 展开更多
关键词 multi-stage heat treatment titanium alloy in-situ tension MICROSTRUCTURE mechanical properties
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