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Memory effect in time fractional Schrödinger equation
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作者 祖传金 余向阳 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期216-221,共6页
A significant obstacle impeding the advancement of the time fractional Schrodinger equation lies in the challenge of determining its precise mathematical formulation.In order to address this,we undertake an exploratio... A significant obstacle impeding the advancement of the time fractional Schrodinger equation lies in the challenge of determining its precise mathematical formulation.In order to address this,we undertake an exploration of the time fractional Schrodinger equation within the context of a non-Markovian environment.By leveraging a two-level atom as an illustrative case,we find that the choice to raise i to the order of the time derivative is inappropriate.In contrast to the conventional approach used to depict the dynamic evolution of quantum states in a non-Markovian environment,the time fractional Schrodinger equation,when devoid of fractional-order operations on the imaginary unit i,emerges as a more intuitively comprehensible framework in physics and offers greater simplicity in computational aspects.Meanwhile,we also prove that it is meaningless to study the memory of time fractional Schrodinger equation with time derivative 1<α≤2.It should be noted that we have not yet constructed an open system that can be fully described by the time fractional Schrodinger equation.This will be the focus of future research.Our study might provide a new perspective on the role of time fractional Schrodinger equation. 展开更多
关键词 time fractional Schrodinger equation memory effect non-Markovian environment
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The superiority of PMFs on reversing drug resistance of colon cancer and the effect on aerobic glycolysis-ROS-autophagy signaling axis
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作者 YUQIN YIN YU WU +6 位作者 HONGLIANG HUANG YINGYING DUAN ZHONGWEN YUAN LIHUI CAO JINJIN YING YONGHENG ZHOU SENLING FENG 《Oncology Research》 SCIE 2024年第12期1891-1902,共12页
Background:Polymethoxylatedflavones(PMFs)are compounds present in citrus peels and other Rutaceae plants,which exhibit diverse biological activities,including robust antitumor and antioxidant effects.However,the mechan... Background:Polymethoxylatedflavones(PMFs)are compounds present in citrus peels and other Rutaceae plants,which exhibit diverse biological activities,including robust antitumor and antioxidant effects.However,the mechanism of PMFs in reversing drug resistance to colon cancer remains unknown.In the present study,we aimed to investigate the potential connection between the aerobic glycolysis-ROS-autophagy signaling axis and the reversal of PTX resistance in colon cancer by PMFs.Methods:MTT Cell viability assay and colony formation assay were used to investigate the effect of PMFs combined with PTX in reversing HCT8/T cell resistance ex vivo;the mRNA and protein levels of the target were detected by SDS-PAGE(sodium dodecyl sulfate-polyacrylamide gel electrophoresis),quantitative real-timefluorescence polymerase chain reaction(qRT-PCR)and Western blot protein immunoblotting(WB);An HCT8/T cell xenograft model was established to investigate the MDR reversal activity of PMFs in vivo;The extracellular acidification rate(ECAR)and the oxygen consumption rate(OCR)were detected to assess the cellular oxygen consumption rate and glycolytic process.Results:HCT8/T cells demonstrated significant resistance to PTX,up-regulating the expression levels of ABCB1 mRNA,P-gp,LC3-I,and LC3-II protein,and increasing intracellular reactive oxygen species(ROS)content.PMFs mainly contain two active ingredients,nobiletin,and tangeretin,which were able to reverse drug resistance in HCT8/T cells in a concentration-dependent manner.PMFs exhibited high tolerance in the HCT8/T nude mouse model while increasing the sensitivity of PTX-resistant cells and suppressing tumor growth significantly.PMFs combined with PTX reduced extracellular acidification rate(ECAR)and oxygen consumption rate(OCR)in HCT8/T cells.Additionally,PMFs reduced intracellular ROS content,down-regulated the expression levels of autophagy-related proteins LC3-I,LC3-II,Beclin1,and ATG7,and significantly reduced the number of autophagosomes in HCT8/T cells.Conclusions:The present study demonstrated that PMFs could potentially reverse PTX resistance in colon cancer by regulating the aerobic glycolysis-ROS-autophagy signaling axis,which indicated that PMFs would be potential potentiators for future chemotherapeutic agents in colon cancer. 展开更多
关键词 Polymethoxylated flavones(PMFs) Colon cancer drug resistance Aerobic glycolysis-ROS-autophagy Warburg effect
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Vitamin D,selenium,and antidiabetic drugs in the treatment of type 2 diabetes mellitus with Hashimoto's thyroiditis 被引量:2
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作者 Fen Feng Bin Zhou +3 位作者 Ci-La Zhou Ping Huang Gang Wang Kuang Yao 《World Journal of Diabetes》 SCIE 2024年第2期209-219,共11页
BACKGROUND Diabetes and thyroiditis are closely related.They occur in combination and cause significant damage to the body.There is no clear treatment for type-2 diabetes mellitus(T2DM)with Hashimoto's thyroiditis... BACKGROUND Diabetes and thyroiditis are closely related.They occur in combination and cause significant damage to the body.There is no clear treatment for type-2 diabetes mellitus(T2DM)with Hashimoto's thyroiditis(HT).While single symptomatic drug treatment of the two diseases is less effective,combined drug treatment may improve efficacy.AIM To investigate the effect of a combination of vitamin D,selenium,and hypoglycemic agents in T2DM with HT.METHODS This retrospective study included 150 patients with T2DM and HT treated at The Central Hospital of Shaoyang from March 2020 to February 2023.Fifty patients were assigned to the control group,test group A,and test group B according to different treatment methods.The control group received low-iodine diet guidance and hypoglycemic drug treatment.Test group A received the control treatment plus vitamin D treatment.Test group B received the group A treatment plus selenium.Blood levels of markers of thyroid function[free T3(FT3),thyroid stimulating hormone(TSH),free T4(FT4)],autoantibodies[thyroid peroxidase antibody(TPOAB)and thyroid globulin antibody(TGAB)],blood lipid index[low-density lipoprotein cholesterol(LDL-C),total cholesterol(TC),triacylglycerol(TG)],blood glucose index[fasting blood glucose(FBG),and hemoglobin A1c(HbA1c)]were measured pre-treatment and 3 and 6 months after treatment.The relationships between serum 25-hydroxyvitamin D3[25(OH)D3]level and each of these indices were analyzed.RESULTS The levels of 25(OH)D3,FT3,FT4,and LDL-C increased in the order of the control group,test group A,and test group B(all P<0.05).The TPOAB,TGAB,TC,TG,FBG,HbA1c,and TSH levels increased in the order of test groups B,A,and the control group(all P<0.05).All the above indices were compared after 3 and 6 months of treatment.Pre-treatment,there was no divergence in serum 25(OH)D3 level,thyroid function-related indexes,autoantibodies level,blood glucose,and blood lipid index between the control group,test groups A and B(all P>0.05).The 25(OH)D3 levels in test groups A and B were negatively correlated with FT4 and TGAB(all P<0.05).CONCLUSION The combination drug treatment for T2DM with HT significantly improved thyroid function,autoantibody,and blood glucose and lipid levels. 展开更多
关键词 Type-2 diabetes mellitus Hashimoto's thyroiditis Vitamin D Selenium agent Hypoglycemic drugs Curative effect
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Why Don’t We Adequately Identify and Manage Adverse Drug Reactions despite Having the Needed Information?
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作者 Mark J. Kupersmith Karl Kieburtz 《Health》 2024年第2期148-159,共12页
Importance/Objective: Adverse Drug Reactions (ADRs) are unavoidable, but recognizing and addressing ADRs early can improve wellness and prevent permanent injury. We suggest that available medical information and digit... Importance/Objective: Adverse Drug Reactions (ADRs) are unavoidable, but recognizing and addressing ADRs early can improve wellness and prevent permanent injury. We suggest that available medical information and digital/electronic methods could be used to manage this major healthcare problem for individual patients in real time. Methods: We searched the available digital applications and three literature databases using the medical subject heading terms, adverse drug reaction reporting systems or management, filtered by clinical trial or systemic reviews, to detect publications with data about ADR identification and management approaches. We reviewed the reports that had abstract or summary data or proposed or implemented methods or systems with potential to identify or manage ADRs in clinical settings. Results: The vast majority of the 481 reports used retrospectively collected data for groups of patients or were limited to surveying one population group or class of medication. The reports showed potential and definite associations of ADRs for specific drugs and problems, mostly, but not exclusively, for patients in hospitals and nursing homes. No reports described complete methods to collect comprehensive data on ADRs for individual patients in a healthcare system. The digital applications have ADR information, but all are too cumbersome or incomplete for use in active clinical settings. Several studies suggested that providing information about potential ADRs to clinicians can reduce these problems. Conclusion and Relevance: Although investigators and government agencies agree with the need, there is no comprehensive ADR management program in current use. Informing the patient’s healthcare practitioners of potential ADRs at the point of service has the potential for reduction of these complications, which should improve healthcare and reduce unneeded costs. 展开更多
关键词 Adverse drug Reaction Medication Side effect Identification Medication Complication Medication Safety
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Effect of Ultrasound-Guided Transversus Abdominis Plane Block Combined with Lornoxicam on Pain and Recovery Quality After Abdominal Surgery in Patients with Drug Addiction
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作者 Ling Luo Zhouxu Yang Hongtao Yang 《Journal of Clinical and Nursing Research》 2023年第5期89-96,共8页
Objective:This paper aims to analyze the analgesic effect of ultrasound-guided transversus abdominis plane block(TAPB)combined with non-steroidal anti-inflammatory analgesic drug lornoxicam on abdominal surgery in pat... Objective:This paper aims to analyze the analgesic effect of ultrasound-guided transversus abdominis plane block(TAPB)combined with non-steroidal anti-inflammatory analgesic drug lornoxicam on abdominal surgery in patients with a history of drug addiction.Methods:32 patients aged 18-60 who underwent lower abdominal surgery in the First People's Hospital of Liangshan Yi Autonomous Prefecture and Butuo County People's Hospital of Liangshan Yi Autonomous Prefecture from January 2022 to March 2023 were selected,the patients must have drug abuse history for more than 1 year,with a history of drug withdrawal and relapse.The patients were divided into observation group and control group by the envelope method,with 16 cases in the observation group and 16 cases in the control group.Two groups of patients underwent ultrasound-guided bilateral transversus abdominis plane block after the operation.The observation group was treated with dexmedetomidine hydrochloride 1μg/kg+0.25%ropivacaine hydrochloride 40ml,and the control group was treated with 40ml 0.9%sodium chloride injection,the two groups of patients returned to the ward after operation and given intravenous infusion of lornoxicam for relieving the pain.The visual analogue scale(VAS)score of postoperative pain,the times of rescue analgesia,the time of postoperative anal exhaust,the time of ambulation,nausea and vomiting,withdrawal symptoms,related adverse reactions,and hospitalization days were compared between the two groups.Results:The VAS score of postoperative pain in the observation group was significantly lower than that in the control group,P<0.05.Patients in the observation group used less postoperative rescue analgesics than those in the control group,P<0.05.For postoperative anal exhaust time,the difference between the two groups of patients was relatively small,and the time in the observation group was shorter,P>0.05.The time to get out of bed and the length of hospital stay were not significantly different between the control group and the observation group,P>0.05.The withdrawal symptoms of the patients in the observation group were better,P<0.05,nausea and vomiting,and other adverse reactions were lower in the control group,P<0.05.Conclusion:Ultrasound-guided transversus abdominis plane block combined with lornoxicam can be used to relieve pain in abdominal surgery for patients with drug addiction,which can effectively improve the therapeutic effect of patients and reduce the number of postoperative rescue analgesia.Thus,it has high clinical application value. 展开更多
关键词 Ultrasound-guided transversus abdominis plane block LORNOXICAM Patients with drug addiction Nursing effect
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Drug-Drug Interactions in Patients with Breast Cancer
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作者 Balaram Gudapati Terry Oroszi 《Journal of Biosciences and Medicines》 2024年第9期113-131,共19页
The research paper investigates the intricate landscape of drug-drug interactions (DDIs) within the context of breast cancer treatment, with a particular focus on the elderly population and the use of complementary an... The research paper investigates the intricate landscape of drug-drug interactions (DDIs) within the context of breast cancer treatment, with a particular focus on the elderly population and the use of complementary and alternative medicine (CAM). The study underscores the heightened susceptibility of elderly patients to DDIs due to the prevalence of polypharmacy and the widespread utilization of CAM among breast cancer patients. The potential ramifications of DDIs, encompassing adverse drug events and diminished treatment efficacy, are elucidated. The paper accentuates the imperative for healthcare providers to comprehensively understand both conventional and CAM therapies, enabling them to provide patients with informed guidance regarding safe and efficacious treatment options, culminating in enhanced patient outcomes. 展开更多
关键词 Breast Cancer drug-drug Interactions POLYPHARMACY Side effects Anti-Cancer drug Failure Complementary and Alternative Medicine
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Influence of recovery heating rate on shape memory effect in up-quenched Cu-Al-Mn alloy
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作者 王珊玲 杨琴 +2 位作者 李小兰 彭华备 文玉华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第10期3196-3200,共5页
The effect of recovery heating rate on shape memory effect of the up-quenched Cu-8.88Al-10.27Mn(mass fraction, %) alloy was investigated by optical microscopy, electron transmission microscopy(TEM) and electrical ... The effect of recovery heating rate on shape memory effect of the up-quenched Cu-8.88Al-10.27Mn(mass fraction, %) alloy was investigated by optical microscopy, electron transmission microscopy(TEM) and electrical resistivity measurement. It is found that the shape recovery rate decreases as the heating rate decreases. It can reach 75% when the heating rate is 20 ℃/min, while it is only 8% when the heating rate is 1 ℃/min. In situ microstructure observation indicates that the dependence of shape memory effect on recovery heating rate is caused by the stabilization of twinned martensite induced by deformation. The analysis of electrical resistivity shows that the stabilization of twinned martensite may be ascribed to formation of compound defects of vacancies and dislocations at the boundaries of twinned martensite during the slow heating. The compound defects prevent the reverse transformation of twinned martensite. 展开更多
关键词 Cu-Al-Mn alloy shape memory effect martensitic phase transformation TWINNING
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Memory effect on the pressure-temperature condition and induction time of gas hydrate nucleation 被引量:13
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作者 Qiang Wu Baoyong Zhang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2010年第4期446-451,共6页
The focus of this study is to investigate the influence of memory effect and the relation of its existence with the dissociation temperature,using gas hydrate formation and dissociation experiments.This is beneficial ... The focus of this study is to investigate the influence of memory effect and the relation of its existence with the dissociation temperature,using gas hydrate formation and dissociation experiments.This is beneficial because memory effect is considered as an effective approach to promote the thermodynamic and dynamic conditions of gas hydrate nucleation.Seven experimental systems (twenty tests in total) were performed in a 1 L pressure cell.Three types of hydrate morphology,namely massive,whiskery and jelly crystals were present in the experiments.The pressures and temperatures at the time when visual hydrate crystals appeared were measured.Furthermore,the influence of memory effect was quantified in terms of pressure-temperature-time (p-T-t) relations.The results revealed that memory effect could promote the thermodynamic conditions and shorten the induction time when the dissociation temperature was not higher than 25℃.In this study,the nucleation superpressure and induction time decrease gradually with time of tests,when the earlier and the later tests are compared.It is assumed that the residual structure of hydrate dissociation,as the source of the memory effect,provides a site for mass transfer between host and guest molecules.Therefore,a driving force is created between the residual structures and its surrounding bulk phase to promote the hydrate nucleation.However,when the dissociation temperature was higher than 25 ℃,the memory effect vanished.These findings provide references for the application of memory effect in hydrate-based technology. 展开更多
关键词 gas hydrate memory effect NUCLEATION THERMODYNAMICS induction time
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The Assessment of the Clinical Effect of the Drug Compatibility and Course of Treatment to the Brucellar Spondylitis 被引量:50
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作者 Xin-Ming Yang Wei Shi +4 位作者 Xian-Yong Meng Ying Zhang Ya-Kun Du Lei Zhang Yao-Yi Wang 《Surgical Science》 2013年第1期92-99,共8页
Objective: To evaluate five drug treatment regimens in the treatment of Brucella spondylitis. Methods: Patients with clinical symptoms compatible and diagnostic test consistent with Brucella spondylitis were randomly ... Objective: To evaluate five drug treatment regimens in the treatment of Brucella spondylitis. Methods: Patients with clinical symptoms compatible and diagnostic test consistent with Brucella spondylitis were randomly assigned to five drug treatment regimens. Results: Combination therapy with doxycycline, rifampin and sulfamethoxazole for 56 consecutive days showed the highest cure rate of 20% after a single course and of 85% after a double course with affectivity rates of 55% and 95%. Cure rate and affectivity rate was significant better (P 0.05) than for patients receiving doxycycline, rifampin and streptomycin for the same period and regimens containing doxycycline were significant better than regimens without this drug. Conclusion: Combination therapy of doxycycline, rifampin and sulfamethoxazole for 8 weeks using one or two full courses should be recommended for Brucella spondylitis. 展开更多
关键词 BRUCELLOSIS SPONDYLITIS CLINIC effect COURSE of TREATMENT drug Compatibility
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STABILIZATION OF MARTENSITE IN Cu-Zn-Al ALLOY AND ITS REVERSE SHAPE MEMORY EFFECT 被引量:5
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作者 Cheng Yan and Wang Mingpu Department of Materials Science and Engineering, Central South University of Technology, Changsha 410083, P. R. China 《中国有色金属学会会刊:英文版》 CSCD 1998年第4期121-125,共5页
INTRODUCTIONThestabilizationofmartensitereferstothephenomenonthatthereversetransformationstartandfinishtempe... INTRODUCTIONThestabilizationofmartensitereferstothephenomenonthatthereversetransformationstartandfinishtemperatures(AsandAf)i... 展开更多
关键词 SMA STABILIZATION of MARTENSITE REVERSE SHAPE memory effect
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SHAPE MEMORY EFFECT OF PU IONOMERS WITH IONIC GROUPS ON HARD-SEGMENTS 被引量:6
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作者 胡金莲 Kwok-wing Yeung 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2006年第2期173-186,共14页
SMPU (shape memory polyurethane) non-ionomers and ionomers, synthesized with poly(c-caprolactone) (PCL), 4, 4'-diphenylmethane diisocyanate (MDI), 1,4-butanediol (BDO), dimethylolpropionic acid (DMPA) wer... SMPU (shape memory polyurethane) non-ionomers and ionomers, synthesized with poly(c-caprolactone) (PCL), 4, 4'-diphenylmethane diisocyanate (MDI), 1,4-butanediol (BDO), dimethylolpropionic acid (DMPA) were measured with cyclic tensile test and strain recovery test. The relations between the structure and shape memory effect of these two series were studied with respect to the ionic group content and the effect of neutralization. The resulting data indicate that, with the introduction of asymmetrical extender, the stress at 100% elongation is decreased for PU non-ionomer and ionomer series, especially lowered sharply for non-ionomer series; the fixation ratio of ionomer series is not affected obviously by the ionic group content; the total recovery ratio of ionomer series is decreased greatly. After sufficient relaxation time for samples stretched beforehand, the switching temperature is raised slightly, whereas the recovery ratio measured with strain recovery test method is lowered with increased DMPA content. The characterization with FT-IR, DSC, DMA elucidated that, the ordered hard domain of the two series is disrupted with the introduction of DMPA which causes more hard segments to dissolve in soft phase; ionic groups on hard segment enhance the cohesion between hard segments especially at high ionic group content and significantly facilitate the phase separation compared with the corresponding non-ionomer at moderate ionic group content. 展开更多
关键词 Polyurethane IONOMERS Cyclic thermo-mechanical investigations Shape memory effect Cyclic tensile test Strain recovery test.
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A macroscopic multi-mechanism based constitutive model for the thermo-mechanical cyclic degeneration of shape memory effect of NiTi shape memory alloy 被引量:6
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作者 Chao Yu Guozheng Kang Qianhua Kan 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2017年第3期619-634,共16页
A macroscopic based multi-mechanism constitutive model is constructed in the framework of irreversible thermodynamics to describe the degeneration of shape memory effect occurring in the thermo-mechanical cyclic defor... A macroscopic based multi-mechanism constitutive model is constructed in the framework of irreversible thermodynamics to describe the degeneration of shape memory effect occurring in the thermo-mechanical cyclic deformation of NiTi shape memory alloys (SMAs). Three phases, austenite A, twinned martensite and detwinned martensite , as well as the phase transitions occurring between each pair of phases (, , , , and are considered in the proposed model. Meanwhile, two kinds of inelastic deformation mechanisms, martensite transformation-induced plasticity and reorientation-induced plasticity, are used to explain the degeneration of shape memory effects of NiTi SMAs. The evolution equations of internal variables are proposed by attributing the degeneration of shape memory effect to the interaction between the three phases (A, , and and plastic deformation. Finally, the capability of the proposed model is verified by comparing the predictions with the experimental results of NiTi SMAs. It is shown that the degeneration of shape memory effect and its dependence on the loading level can be reasonably described by the proposed model. 展开更多
关键词 NiTi SMAs Constitutive model Cyclic degeneration of shape memory effect Transformation-induced plasticity Reorientation-induced plasticity
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Role of thermal martensite in shape memory effect of CoAl and CoNi alloys
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作者 吴冰洁 杨潇 +1 位作者 彭华备 文玉华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第2期382-389,共8页
To address the role of the HCP martensite in CoAl and CoNi shape memory alloys, the relationship between the shape memory effect (SME) and the content of the thermal and stress-induced HCP martensite was invest... To address the role of the HCP martensite in CoAl and CoNi shape memory alloys, the relationship between the shape memory effect (SME) and the content of the thermal and stress-induced HCP martensite was investigated in the solution-treated CoAl and CoNi alloys. In-situ optical observations were employed to investigate the contents of thermal HCP martensite before and after deep cooling and its influence on the stress-induced HCP martensite transformation and SME. The results show that the SME in both the CoAl and the CoNi alloys results from the stress-induced HCP martensite. The role of the thermal HCP martensite in both of them is the strengthening of the matrix. The much higher yield strength in the solution-treated CoAl alloy due to solution strengthening of Al is responsible for its better SME compared with the CoNi alloy. 展开更多
关键词 CoAl alloy CoNi alloy shape memory effect thermal HCP martensite stress-induced HCP martensite solution strengthening
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Characterization of the Elastic-plastic Region Based on Magnetic Memory Effect 被引量:3
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作者 LENG Jiancheng XU Minqiang +1 位作者 LI Jianwei ZHANG Jiazhong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第4期532-536,共5页
Detecting stress concentration, especially critical stress state leading to structure damage or failure, is one of the most important tasks of equipment diagnosis. Metal magnetic memory technique needs further researc... Detecting stress concentration, especially critical stress state leading to structure damage or failure, is one of the most important tasks of equipment diagnosis. Metal magnetic memory technique needs further research to evaluate stress concentration quantitatively due to ambiguous physical mechanism, though it has potential to detect early defects in ferromagnetic materials. Mild Q235 steel defective specimens in demagnetization state were loaded in tension up to visible necking, with magnetic memory signals measurement made at increasing stress levels. Magnetic signals varied greatly under first several loadings and subsequently tended to stability in the elastic region, which showed that the magnetization always approaches the anhysteretic magnetization curve and was explained by the theory of magnetomechanical effect. In the plastic stage, an abnormal wave occurred in the stress concentration zone and its height value was sensitive to plastic deformation levels and dependent on the distance between the probe and defect, in accordance with the simulation results based on the magnetic dipole model. Different magnetic signal characteristics in the elastic-plastic region indicate that the magnetic memory technique can identify macroyielding and early damage, which is of profound significance for ensuring safe operation of equipment in service. 展开更多
关键词 metal magnetic memory plastic deformation magnetomechanical effect magnetic dipole model abnormal wave
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Buckling-controlled two-way shape memory effect in a ring-shaped bilayer 被引量:4
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作者 Hao Li Xiaoyan Liang Weibin Song 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2019年第6期1217-1225,共9页
Shape memory polymers(SMPs)usually have a one-way shape memory effect.In this paper,an easy-operating method to realize a two-way shape memory effect was demonstrated in a ring-shaped bilayer structure where the two l... Shape memory polymers(SMPs)usually have a one-way shape memory effect.In this paper,an easy-operating method to realize a two-way shape memory effect was demonstrated in a ring-shaped bilayer structure where the two layers are SMPs with different thermal transition temperatures.By designing specific thermomechanical processes,the mismatched deformation between the two layers leads to a morphology change of ring-shaped bilayer structures from a smooth ring to a gear-like buckling shape under cooling and a reversible recovery to the smooth shape under heating.Such a morphology change is ascribed to occurrence and recovery of thermoelastic buckling.This method was validated by finite element simulation.We experimentally investigated the influence of pre-strain on buckling,and it was found that both the buckling occurrence and recovery temperature vary with pre-strain.Furthermore,considering a ring-shaped SMP-SMP bilayer structure,finite element analysis was conducted to study the influence of film thickness and modulus ratio of two layers on buckling behavior.The results showed that the critical buckling wavelength was greatly influenced by film thickness and modulus ratio.W e made a theoretical analysis that accorded well with the numerical results. 展开更多
关键词 Shape memory polymers Two-way shape memory effect BUCKLING Ring-shaped BILAYER
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Kongsheng Zhenzhong pill's effect on the learning and memory ability and its neuroprotective effects in vascular dementia rats 被引量:3
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作者 Xuming Ji Huayun Yu +4 位作者 Bin Ouyang Guowei Liu Zhichun Wu Heng Liu Fang Du 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第30期2342-2346,共5页
Clinical reports have demonstrated that the Kongsheng Zhenzhong pill (KSZZP), a classical prescription deriving from Valuable Prescription for Emergencies, has good therapeutic effects on vascular dementia. However,... Clinical reports have demonstrated that the Kongsheng Zhenzhong pill (KSZZP), a classical prescription deriving from Valuable Prescription for Emergencies, has good therapeutic effects on vascular dementia. However, the mechanisms that mediate its effects remain unclear. In this study, the expression of N-methyI-D-aspartate receptor 1 mRNA, the content of nitric oxide, and the concentration of calcium in neurons was determined with in situ hybridization, spectrophotometry and flow cytometry, respectively. In addition, the expressions of N-methyI-D-aspartate receptor 1, nerve growth factor protein, and glial cell line-derived neurotrophic factor protein were detected with immunohistochemistry. We found that KSZZP could significantly decrease the expression of N-methyI-D-aspartate receptor 1 mRNA and protein, the content of nitric oxide, and the concentration of calcium in neurons. KSZZP also increased the expression of nerve growth factor and glial cell line-derived neurotrophic factor protein in the hippocampus CA1 region and in the cerebral cortex. Morris water maze and passive avoidance tests verified that KSZZP ameliorated the cognitive impairments of vascular dementia rats. Moreover, the KSZZP-induced improvements in the cognitive functions of vascular dementia rats were correlated with both inhibition of N-methyl-D-aspartate-induced excitable neurotoxicity and elevation of neurotrophic factor expression. 展开更多
关键词 Kongsheng Zhenzhong pill vascular dementia learning and memory ability neuroprotective effects
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Compressive mechanical properties and shape memory effect of NiTi gradient lattice structures fabricated by laser powder bed fusion 被引量:9
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作者 Wei Chen Dongdong Gu +3 位作者 Jiankai Yang Qin Yang Jie Chen Xianfeng Shen 《International Journal of Extreme Manufacturing》 SCIE EI CAS 2022年第4期189-205,共17页
Laser additive manufacturing (AM) of lattice structures with light weight, excellent impact resistance, and energy absorption performance is receiving considerable attention in aerospace, transportation, and mechanica... Laser additive manufacturing (AM) of lattice structures with light weight, excellent impact resistance, and energy absorption performance is receiving considerable attention in aerospace, transportation, and mechanical equipment application fields. In this study, we designed four gradient lattice structures (GLSs) using the topology optimization method, including the unidirectional GLS, the bi-directional increasing GLS, the bi-directional decreasing GLS and the none-GLS. All GLSs were manufactureed by laser powder bed fusion (LPBF). The uniaxial compression tests and finite element analysis were conducted to investigate the influence of gradient distribution features on deformation modes and energy absorption performance of GLSs. The results showed that, compared with the 45° shear fracture characteristic of the none-GLS, the unidirectional GLS, the bi-directional increasing GLS and the bi-directional decreasing GLS had the characteristics of the layer-by-layer fracture, showing considerably improved energy absorption capacity. The bi-directional increasing GLS showed a unique combination of shear fracture and layer-by-layer fracture, having the optimal energy absorption performance with energy absorption and specific energy absorption of 235.6 J and 9.5 J g-1 at 0.5 strain, respectively. Combined with the shape memory effect of NiTi alloy, multiple compression-heat recovery experiments were carried out to verify the shape memory function of LPBF-processed NiTi GLSs. These findings have potential value for the future design of GLSs and the realization of shape memory function of NiTi components through laser AM. 展开更多
关键词 additive manufacturing laser powder bed fusion gradient lattice structures deformation behavior shape memory effect
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EFFECTS OF HEAT TREATMENT ON TENSILE PROPERTIES AND SHAPE MEMORY EFFECTS OF Ni-Ti-Nb ALLOY 被引量:2
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作者 Zheng Yufeng, Cai Wei, Luo Yichun, Zhao Liancheng School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 《中国有色金属学会会刊:英文版》 CSCD 1997年第4期93-97,共5页
EFFECTSOFHEATTREATMENTONTENSILEPROPERTIESANDSHAPEMEMORYEFFECTSOFNiTiNbALLOY①ZhengYufeng,CaiWei,LuoYichun,Z... EFFECTSOFHEATTREATMENTONTENSILEPROPERTIESANDSHAPEMEMORYEFFECTSOFNiTiNbALLOY①ZhengYufeng,CaiWei,LuoYichun,ZhaoLianchengSchoo... 展开更多
关键词 Ni Ti Nb ALLOY HEAT treatment TENSILE PROPERTIES SHAPE memory effect
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Effects of Predeformation on the Reverse Martensitic Transformation of TiNi Shape Memory Alloy 被引量:14
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作者 Yanjun ZHENG Lishan CUI +1 位作者 Fan ZHANG Dazhi YANG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第6期611-614,共4页
DSC was used to study the effects of predeformation on the reverse martensitic transformation of near-equiatomic TiNi alloy. Both the start temperature As and the finish temperature Af of the reverse transformation in... DSC was used to study the effects of predeformation on the reverse martensitic transformation of near-equiatomic TiNi alloy. Both the start temperature As and the finish temperature Af of the reverse transformation increased with increasing degree of predeformation, but the algebraic difference between As and Af decreased with increasing predeformation until it reached a minimum value, then remained unchanged with further deformation. Transformation heat also increased with increasing predeformation until it reached a maximum value, then decreased with further predeformation. All the phenomena above were considered to be closely related with the release of elastic strain energy during predeformation. 展开更多
关键词 TINI effects of Predeformation on the Reverse Martensitic Transformation of TiNi Shape memory Alloy
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EFFECT OF DYNAMIC RECRYSTALLIZATION ON SHAPE MEMORY EFFECT IN Fe-Mn-Si BASED ALLOYS 被引量:2
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作者 L.J. Rong Y. Y. Li and C.X. Shi(Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110015, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1996年第5期361-366,共6页
Improvement of shape, memory effect (SME) in Fe-Mn-Si based alloys has been investigated, compared with that by conventional 'training' treatment. It is found that SME in Fe-Mn-Si alloy can be greatly improved... Improvement of shape, memory effect (SME) in Fe-Mn-Si based alloys has been investigated, compared with that by conventional 'training' treatment. It is found that SME in Fe-Mn-Si alloy can be greatly improved by ausforming and 3.8%recovery strain and 2.2% complete recovery strain can be reached by ausforming at 973 K when dynamic recrystallization has just occurred. The mechanism for the improvement of SME is proposed. 展开更多
关键词 shape memory effect dynamic recrystallization Fe-Mn-Si based Alloy
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