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In vivo sedative and muscle relaxants activity of Diospyros lotus L 被引量:1
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作者 Abdur Rauf Ghias Uddin +1 位作者 Bina Shaheen Siddiqui Haroon Khan 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2015年第4期277-280,共4页
Objective: To evaluate the sedative effect of Diospyros lotus L(D. lotus) extract in mice using the open field and Rota rod tests.Methods: For the sedative and muscle relaxants activities of extract/fractions of the p... Objective: To evaluate the sedative effect of Diospyros lotus L(D. lotus) extract in mice using the open field and Rota rod tests.Methods: For the sedative and muscle relaxants activities of extract/fractions of the plant, invivo open field and phenobarbitone-induced sleeping time were used, while the Roda rod test was employed in animals for the assessment of muscle relaxant activity.Results: Results from this investigation revealed that the extracts of D. lotus have exhibited significant sedative effect in mice(45.98%) at 100 mg/kg i.p. When the extract was partitioned with different solvents, the n-hexane fraction was inactive whereas the chloroform fraction was the most active with 82.67% sedative effect at 50 and 100 mg/kg i.p. On the other hand,the ethyl acetate and n-butanol fractions displayed significant sedative effects(55.65% and40.87%, respectively) at 100 mg/kg i.p. Among the tested extract/fractions, only chloroform and ethyl acetate fractions showed significant(P < 0.05) muscle relaxant activity in the Rota rod test.Conclusions: In short, our study provided scientific background to the traditional uses of D.lotus as sedative. 展开更多
关键词 DIOSPYROS LOTUS EBENACEAE SEDATIVE MUSCLE relaxants ACTIVITY
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Relaxant Effects of Quercetin and Rutin on Human Isolated Bronchus 被引量:1
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作者 Hanifa Djelili Lekhmici Arrar +1 位作者 Emmanuel Naline Philippe Devillier 《Chinese Medicine》 2012年第2期94-100,共7页
Increasing epidemiological evidence supports the view, that quercetin has protective roles in a multitude of disease states in human who have a high intake of polyphenols. To investigate the ability of quercetin and i... Increasing epidemiological evidence supports the view, that quercetin has protective roles in a multitude of disease states in human who have a high intake of polyphenols. To investigate the ability of quercetin and its rutinoside, rutin, to modulate the relaxation of human airways smooth muscle and to determine the mechanism (s) of such relaxation, isolated human bronchus rings were suspended in individual organ baths, precontracted with acetylcholine or with histamine and the relaxing effects of quercetin and rutin were determined by measurement of isometric tension. Quercetin induced concentration-dependent relaxant responses on acetylcholine or histamine precontracted human bronchial rings and with almost equal effectiveness. In terms of potency (pD2) and efficacy (Emax), quercetin is more potent than rutin on relaxant responses of human bronchus. K+ and Ca2+ concentration-dependent contraction curves were inhibited after incubation with increasing concentrations of quercetin. Quercetin potentiated in a concentration-dependent manner the relaxant effects of isoprenaline or sodium nitroprusside. Rutin had no effect on K+-induced contraction and on relaxant activity of isoprenaline or sodium nitroprusside. Our results suggest that the bronchodilator effects of quercetin are modulated by an increase in cyclic nucleotide levels as well as an alteration in availability of Ca2+ to the contractile machinery. 展开更多
关键词 Calcium Channels Cyclic NUCLEOTIDE HUMAN BRONCHUS QUERCETIN relaxant EFFECTS RUTIN
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Evaluation of the anticonvulsant and muscle relaxant effects of the methanol root bark extracts of Annona senegalensis
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作者 Okoye TC Akah PA Omeke CP 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2010年第1期25-28,共4页
Objective:To investigate the potentials of the root bark of Annona(A.) senegalensis in the control of seizure and related hypnotic and motor incoordination effects in mice using experimental models.Methods:The metha... Objective:To investigate the potentials of the root bark of Annona(A.) senegalensis in the control of seizure and related hypnotic and motor incoordination effects in mice using experimental models.Methods:The methanol extract(ME) of the root bark of A.senegalensis was studied in mice using pentylenetetrazole(PTZ) induced convulsions,phenobarbitone induced sleeping time and motor coordination test on rota-rod performance.Acute toxicity and lethality(LD50) lest as well as phytochemical analysis were also carried out.Results:The extract(200,400,800 mg/ kg) exhibited a non- dose dependent significant(P【0.05) delay in the onset of both tonic and clonic phases of seizure induced by PTZ(60 mg/kg,s.c.) as well as offered a 100%protection (200 mg/kg) in mice from PTZ induced seizures.The extract significantly(P【0.05) decreased the latency and increased the duration of phenobarbitone induced sleeping time.At 200 mg/kg, the extract exhibited a significant(P【0.05) motor incoordination.The acute toxicity test revealed an oral LD<sub>50</sub> of 1 2%mg/kg,while the phytochemical studies showed the presence of alkaloids, resins,glycosides,carbohydrate,reducing sugar,flavonoids,terpenoids,saponins and tannins. Conclusion:The extract of A senegalensis possessed anticonvulsant activity with pronounced hypnotic and muscle relaxant effects. 展开更多
关键词 ANNONA senegalensis HYPNOSIS ANTICONVULSANT MUSCLE relaxant
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THE DESIGN AND APPLICATION OF RELAXANT MONITORING SYSTEM
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作者 Zhou Wei Yang Jieqiu +3 位作者 Lin Shujuan Li Yuejie Wang Yuehua Wang Qiang(Inst. of Biomedical Engineering,CAMS,Tianjin 300192,China)Sun Jialan(Tianjin First Centrol Hospital,Tianjin 300192,China) 《Chinese Journal of Biomedical Engineering(English Edition)》 1998年第1期19-21,共3页
The paper introduces a monitoring system of muscle relaxant actionduring the anaesthesia operation,which is based on measurement of acceleration.The monitor consists of an acceleration transducer,a nerve stimlation an... The paper introduces a monitoring system of muscle relaxant actionduring the anaesthesia operation,which is based on measurement of acceleration.The monitor consists of an acceleration transducer,a nerve stimlation and a microcomputer unit.The transducer can be fastened to the thumb,and the signal of thethumb movement in response to ulnar nerve stimulation is measured and registeredin the computing unit. In daily clinical practice it has proved possible,using this newapparatus, to achieve reliable evaluation of nuromuscular transimission functionand to contribute to improve anesthesia quality and patient care. 展开更多
关键词 MUSCLE relaxant NEUROMUSCULAR TRANSMISSION FUNCTION MONITOR
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Relaxant Effects of Matrine on Aortic Smooth Muscles of Guinea Pigs 被引量:6
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作者 JIE ZHENG PING ZHENG +4 位作者 XU ZHOU LIN YAN RU ZHOU XUE-YAN FU GUI-DONG DAI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2009年第4期327-332,共6页
Objective To determine whether matrine, a kind of traditional Chinese medicinal alkaloid, can relax the aortic smooth muscles isolated from guinea pigs and to investigate the mechanism of its relaxant effects. Methods... Objective To determine whether matrine, a kind of traditional Chinese medicinal alkaloid, can relax the aortic smooth muscles isolated from guinea pigs and to investigate the mechanism of its relaxant effects. Methods Phenylephrine or potassium chloride concentration-dependent relaxation response of aortic smooth muscles to matrine was studied in the precontracted guinea pigs. Results Matrine (1×10^-4 mol/L -3.3×10^-3 mol/L) relaxed the endothelium-denuded aortic rings pre-contracted sub-maximally with phenylephrine, in a concentration-dependent manner, and its pre-incubation (3.3× 10^- 3 mol/L) produced a significant rightward shift in the phenylephrine dose-response curve, but had no effects on the potassium chloride-induced contraction. The anti-contractile effect of matrine was not reduced by the highly selective ATP-dependent K^+ channel blocker glibenclamide (10.5 mol/L), either by the non-selective K^+channel blocker tetraethylammonium (10^-3 mol/L), or by the β-antagonist propranolol (10^-5 mol/L). In either "normal" or "Ca^2+-free" bathing medium, the phenylephrine-induced contraction was attenuated by matrine (3.3×10^-3 mol/L), indicating that the vasorelaxation was due to inhibition of intracellular and extracellular Ca^2+ mobilization. Conclusion Matrine inhibits phenylephrine-induced contractions by inhibiting activation of α-adrenoceptor and interfering with the release of intracellular Ca^2+ and the influx of extracellular Ca^2+. 展开更多
关键词 MATRINE AORTA Vascular smooth muscle RELAXATION GUINEA-PIGS CALCIUM
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Relaxant effect and possible mechanism of 17-nor-subincanadine E in rabbit corpora cavernosa
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作者 Otacilio D Benvindo Nilberto RF Nascimento +7 位作者 Claudia F Santos Manasses C Fonteles Edilberto R Silveira Daniel E Uchoa Adriana R Campos Karina MA Cunha Flavia A Santos Vietla S Rao 《Asian Journal of Andrology》 SCIE CAS CSCD 2011年第5期747-753,共7页
Compounds with dual action on cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) may be a treatment option for erectile dysfunction, as they not only promote penile erection but also p... Compounds with dual action on cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) may be a treatment option for erectile dysfunction, as they not only promote penile erection but also prevent the upregulation of phosphodiesterase-5. In this study, we examined the possible relaxant effect and mechanism of 17-nor-subincanadine E (SEC, 0.2-200 pmol I^-1), a plant-derived alkaloid, in rabbit corpus cavernosum (RbCC) strips that had been precontracted by exposure to phenylephrine (10 pmol I^- 1) or a high concentration of K+ (60 mmol I^- 1) in vitro. In addition to SEC's effect on cAMP and cGMP levels, electrical field stimulation (EFS) in phenylephrine-precontracted RbCC and calcium chloride (1-100 mmol I^-1) evoked responses in depolarized RbCC were analysed. SEC relaxed the phenylephrine-precontracted RbCCs in a concentration-dependent manner. Atropine, guanethidine and N-co-nitro-L-arginine methyl ester (L-NAME) did not have any effect on the relaxation of RBCCs. When 1H-1,2,4oxadiazole[4,3-a] quinoxalin-1-one (ODQ) was added, it effectively blocked the relaxant response of SEC. Although SEC enhanced the maximal relaxation produced by sodium nitroprusside (SNP) and forskolin in phenylephrine-precontracted cavernosal smooth muscle, it caused a decrease in the maximal contractile response induced by calcium chloride in depolarized RbCCs. The relaxant effect of SEC was paralleled by an increase in the tissue levels of the Cyclic nucleotides cAMP and cGMP. We conclude that SEC promotes the relaxation of RbCC, possibly favouring cAMP and cGMP accumulation and calcium blockade. This novel mechanism could be useful for patients who do not benefit from phosphodiesterase inhibitors and for those with endothelial and nitrergic dysfunction, such as patients with diabetes, hypertension and dyslipidaemias. 展开更多
关键词 17-nor-subincanadine E cyclic nucleotides electrical field stimulation nitric oxide rabbit corpus cavernosum smoothmuscle relaxation
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The relaxant effect of methanolic extract of yohimbe bark (<i>Pausinystalia yohimbe</i>) on rabbit corpus cavernosum smooth muscles
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作者 Mohamed Hassan Hozeifa Imad Eldin Mohamed Taj Eldin +2 位作者 Mohamed Mohamed Ahmed Elhadi Hassan Mohamed Abd Elwahab Sirag Elteyb Nizar 《Health》 2012年第9期656-659,共4页
Background: Development and maintenance of penile erection requires the relaxation of corpus cavernosum smooth muscle (CCSM) cells and it is essentially mediated by nitric oxide (NO). Pausinystalia yohimbe bark is tra... Background: Development and maintenance of penile erection requires the relaxation of corpus cavernosum smooth muscle (CCSM) cells and it is essentially mediated by nitric oxide (NO). Pausinystalia yohimbe bark is traditionally used for the treatment of erectile dysfunction (ED). Objectives and Methods: This study aimed to evaluate the effects of the methanolic extract of P. yohimbe bark (10 mg/ml) on isolated rabbit corpus cavernosum smooth muscle (CCSM). Results: Methanolic extract of P. yohimbe bark blocked contractions in CCSM induced by adrenergic agonists, through facilitating NO release from the endothelial cells. Conclusion: The obtained results revealed that, methanolic extract of P. yohimbe bark caused relaxation of CCSM that validates its traditional aphrodisiac property, thus it could be used to initiate and maintain erection in cases of erectile dysfunction. 展开更多
关键词 P. yohimbe BARK CORPUS Cavernosum Relaxation NITRIC Oxide APHRODISIAC Erectile Dysfunction
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Contribution of Water and Lipid Soluble Substances in the Relaxant Effects of Tymus Vulgaris Extract on Guinea Pig Tracheal Smooth Muscle in Vitro
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作者 Rana Keyhanmanesh Mohammad Hossien Boskabady +1 位作者 Mohammad Ali Ebrahimi Saadatloo Morteza Boskabady 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2016年第5期377-383,共7页
Objective: To examine the relaxant effects of hydro-ethanolic, macerated aqueous (MA) and lipid- free macerated aqueous (LFMA) extract of Tymus vulgaris on tracheal chains of guinea pigs. Methods: The relaxant e... Objective: To examine the relaxant effects of hydro-ethanolic, macerated aqueous (MA) and lipid- free macerated aqueous (LFMA) extract of Tymus vulgaris on tracheal chains of guinea pigs. Methods: The relaxant effects of five cumulative concentrations of each extract (0.4, 0.8, 1.2, 1.6 and 2.0 g/100 mL) were compared with saline as negative control and five cumulative concentrations of theophylline (0.1, 0.2, 0.4, 0.6 and 0.8 mmol/L) on precontracted tracheal smooth muscle of guinea pig with 60 mmol/L KCl (group 1) and 10 μmol/L methacholine (group 2, n=6 for each group). Results: In group 1 all concentrations of theophylline, three higher concentrations of hydro-ethanolic, two concentrations of LFMA and last concentration of MA extracts showed significant relaxant effects compared with that of saline (P〈0.05 or P〈0.01). Two lower concentrations of LFMA and all concentrations of MA except higher one caused contraction compared with saline (P〈0.05 or 0.01). In group 2 experiments, all concentrations of theophylline, hydro-ethanolic, MA and LFMA extracts showed significant relaxant effects compared to that of saline (P〈0.05 or P〈0.01). In both groups, the relaxant effect of all concentrations of hydro-ethanolic extract were significantly higher than most concentrations of others (P〈0.05 or P〈0.01). The relaxant effect of different concentrations of three extracts were significantly greater in group 2 compared with group 1 experiments (all P〈0.01). There were significantly positive correlations between the relaxant effects and concentrations for theophylline and all extracts in both groups (P〈0.05 or P〈0.01). Conclusion: Hydro-ethanolic extract has a potent weaker relaxant effect for other extracts from Tymus vulgaris on tracheal chains of guinea pigs. 展开更多
关键词 Tymus vulgaris hydro-ethanolic extract macerated aqueous extract lipid-free macerated aqueous extract relaxant effect guinea pig TRACHEAL
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Relaxant Effect of Bioactive Component Compatibility of San-ao Decoction on In vitro Guinea Pig Airway Smooth Muscle:A Dose-Response Relationship Study
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作者 Wen-Jie Song Yan-Ling Fu +3 位作者 Sheng-Lou Ni Jia-Jia Fan Qian Du Hao Zheng 《World Journal of Traditional Chinese Medicine》 CAS 2022年第2期262-272,共11页
Background:Component compatibility is important to the modernization of traditional Chinese medicine.Studies have shown that San-ao decoction(SAD)can treat respiratory diseases by relaxing airway smooth muscle(ASM)and... Background:Component compatibility is important to the modernization of traditional Chinese medicine.Studies have shown that San-ao decoction(SAD)can treat respiratory diseases by relaxing airway smooth muscle(ASM)and reducing airway hyper-responsiveness.However,whether its bioactive components and compatibility also present with similar relaxant effects remains unknown.This study aims to explore the potential relaxant property,dose-response relationship,and underlying mechanisms of the bioactive component compatibility in SAD.Methods:Network pharmacology was primarily used to identify the bioactive components of SAD and uncover its underlying mechanisms.ASM tension force measuring technique was utilized to verify the relaxant and dose-response effects on in vitro guinea pig ASM.Results:We postulated pseudoephedrine hydrochloride(PH),amygdalin(AM),and diammonium glycyrrhizate(DG)to be the bioactive components of SAD,which could effectively relax ASM in a dose-dependent manner on both acetylcholine-induced and spontaneous contraction.Both PH and AM could lead to DG dose–response curve shift.The regression equation of these three bioactive components was Y=-2.048×X_(1)+0.411×X_(2)+14.052×X_(3)(X_(1),X_(2),X_(3)representing PH,AM,and DG,respectively).The underlying mechanisms of these components might be associated with the regulation of smooth muscle contraction.Conclusions:PH,AM,and DG are the bioactive components of SAD,which can relax ASM in a dose–response manner and exert a synergistic effect.Clinically,compatibility of these three bioactive components may serve as a new complementary and alternative treatment for respiratory diseases. 展开更多
关键词 Airway smooth muscle bioactive component compatibility dose–response manner relaxant effect San-ao decoction
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Deep Learning Hybrid Model for Lithium-Ion Battery Aging Estimation and Prediction
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作者 项越 姜波 戴海峰 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第S01期215-222,共8页
The degradation process of lithium-ion batteries is intricately linked to their entire lifecycle as power sources and energy storage devices,encompassing aspects such as performance delivery and cycling utilization.Co... The degradation process of lithium-ion batteries is intricately linked to their entire lifecycle as power sources and energy storage devices,encompassing aspects such as performance delivery and cycling utilization.Consequently,the accurate and expedient estimation or prediction of the aging state of lithium-ion batteries has garnered extensive attention.Nonetheless,prevailing research predominantly concentrates on either aging estimation or prediction,neglecting the dynamic fusion of both facets.This paper proposes a hybrid model for capacity aging estimation and prediction based on deep learning,wherein salient features highly pertinent to aging are extracted from charge and discharge relaxation processes.By amalgamating historical capacity decay data,the model dynamically furnishes estimations of the present capacity and forecasts of future capacity for lithium-ion batteries.Our approach is validated against a novel dataset involving charge and discharge cycles at varying rates.Specifically,under a charging condition of 0.25 C,a mean absolute percentage error(MAPE)of 0.29%is achieved.This outcome underscores the model's adeptness in harnessing relaxation processes commonly encountered in the real world and synergizing with historical capacity records within battery management systems(BMS),thereby affording estimations and prognostications of capacity decline with heightened precision. 展开更多
关键词 lithium-ion battery state of health deep learning relaxation process
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Interfacial DMI in Fe/Pt thin films grown on different buffer layers
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作者 张文君 魏菲 +3 位作者 刘冰 周阳 康仕寿 孙兵 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期712-718,共7页
We study the interfacial Dzyaloshinskii-Moriya interactions(i-DMI)of Fe/Pt bilayers grown on Si substrates with MgO,SiO_(2),or Ta each as a buffer layer on the basis of wave-vector-resolved Brillouin light scattering(... We study the interfacial Dzyaloshinskii-Moriya interactions(i-DMI)of Fe/Pt bilayers grown on Si substrates with MgO,SiO_(2),or Ta each as a buffer layer on the basis of wave-vector-resolved Brillouin light scattering(BLS)measurement.The obtained i-DMI energy values for Fe/Pt on MgO,Ta,and SiO_(2) buffer layers are 0.359,0.321,and 0.274 mJ/m~2,respectively.The large i-DMI value observed in Fe/Pt system on the MgO buffer layer can be attributed to the good interfacial quality and the Rshaba effect at the MgO/Fe interface.Moreover,the MgO/Fe/Pt system,benefiting from better sample quality,exhibits a lower damping factor.Furthermore,layer-resolved first-principles calculations are carried out to gain a more in-depth understanding of the origin of the i-DMI in the Fe/Pt system.The results indicate that in the Fe(110)/Pt(111)system,the substantial DMI energy between Fe spins at the interface is related to a significant change in spin-orbit coupling(SOC)energy in the neighboring Pt layer.In contrast,for the MgO(002)/Fe(002)system,both the DMI and its related SOC energy are concentrated at the interfacial Fe layer.Our investigation will provide a valuable insight into the spintronic community in exploring novel devices with chirality dependence. 展开更多
关键词 Fe/Pt i-DMI BLS ferromagnetic resonance magnetic relaxation
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First-Principles Studies of Structural Evolutions in Cathode Materials LiMO_(2)(M=Co,Mn,Ni)
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作者 Yufeng Sun Xin-Gao Gong Ji-Hui Yang 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第10期129-136,共8页
We explore the structural evolutions of stoichiometric LiMO_(2)using the first-principles calculations combined with the cluster expansion method.We automatically obtain the ground state structures of the stoichiometr... We explore the structural evolutions of stoichiometric LiMO_(2)using the first-principles calculations combined with the cluster expansion method.We automatically obtain the ground state structures of the stoichiometric LiMO_(2)by just considering the cation orderings in the quasi rock-salt structures and the following structural relaxations due to both the atomic size mismatches and the Jahn–Teller distortions.We point out that,on the one hand,the cation orderings are mainly determined by the nearest,the second nearest,and the third nearest cation interactions and can be obtained from the‘phase diagram’we have built using the relative strengths of effective cluster interaction(ECI).On the other hand,the structural relaxations are dominated by the crystal field splitting(CFS)energies,i.e.,structures with larger CFS energies are more stable.By calculating the ECIs and CFS energies for various structures of LiMO_(2),we clearly show how ECI and CFS play roles in determining the structural evolution mechanism of these systems. 展开更多
关键词 method RELAXATION CLUSTER
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Interaction between Surface Acoustic Wave and Quantum Hall Effects
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作者 刘萧 吴蒙蒙 +6 位作者 王任飞 王兴豪 张文锋 董昱江 杜瑞瑞 刘阳 林熙 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第4期105-109,共5页
Surface acoustic wave(SAW)is a powerful technique for investigating quantum phases appearing in twodimensional electron systems.The electrons respond to the piezoelectric field of SAW through screening,attenuating its... Surface acoustic wave(SAW)is a powerful technique for investigating quantum phases appearing in twodimensional electron systems.The electrons respond to the piezoelectric field of SAW through screening,attenuating its amplitude,and shifting its velocity,which is described by the relaxation model.In this work,we systematically study this interaction using orders of magnitude lower SAW amplitude than those in previous studies.At high magnetic fields,when electrons form highly correlated states such as the quantum Hall effect,we observe an anomalously large attenuation of SAW,while the acoustic speed remains considerably high,inconsistent with the conventional relaxation model.This anomaly exists only when the SAW power is sufficiently low. 展开更多
关键词 RELAXATION QUANTUM inconsistent
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Microscopic Magnetism of Nickel-Based Infinite-Layer Superconducting Parent Compounds RNiO_(2)(R=La,Nd):A μSR Study
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作者 Qiong Wu Ying Fu +9 位作者 Le Wang Xuefeng Zhou Shanmin Wang Zihao Zhu Kaiwen Chen Chengyu Jiang Toni Shiroka Adrian D.Hillier Jia-Wei Mei Lei Shu 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第9期133-139,共7页
By using muon spin relaxation(μSR)measurements,we perform a comparative study of the microscopic magnetism in the parent compounds of infinite-layer nickelate superconductors RNiO_(2)(R=La,Nd).In either compound,the ... By using muon spin relaxation(μSR)measurements,we perform a comparative study of the microscopic magnetism in the parent compounds of infinite-layer nickelate superconductors RNiO_(2)(R=La,Nd).In either compound,the zero-fieldμSR spectra down to the lowest measured temperature reveal no long-range magnetic order.In LaNiO_(2),short-range spin correlations appear below T=150 K,and spins fully freeze below T∼10 K.NdNiO_(2)exhibits a more complex spin dynamics driven by the Nd 4f and Ni3d electron spin fluctuations.Further,it shows features suggesting the proximity to a spin-glass state occurring below T=5 K.In both compounds,the spin behavior with temperature is further confirmed by longitudinal-field μSR measurements.These results provide new insight into the magnetism of the parent compounds of the superconducting nickelates,crucial to understanding the microscopic origin of their superconductivity. 展开更多
关键词 order nickel RELAXATION
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3D digital-image correlation insight into generalized relaxation behavior of sandstone under stress and pore pressure coupling
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作者 Cancan Chen Heping Xie +4 位作者 Jiang Xu Seisuke Okubo Shoujian Peng Cunbao Li Minghui Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第7期2516-2536,共21页
The occurrence of geological hazards and the instability of geotechnical engineering structures are closely related to the time-dependent behavior of rock.However,the idealization boundary condition for constant stres... The occurrence of geological hazards and the instability of geotechnical engineering structures are closely related to the time-dependent behavior of rock.However,the idealization boundary condition for constant stress in creep or constant strain in relaxation is not usually attained in natural geological systems.Therefore,generalized relaxation tests that explore the simultaneous changes of stress and strain with time under different stress levels with constant pore-water pressure are conducted in this study.The results show that in area Ⅰ,area Ⅱ,and area Ⅲ,the stress and strain both change synchronously with time and show similar evolutionary laws as the strain-time curve for creep or the stress-time curve for relaxation.When the applied stress level surpasses the δ_(ci) or δ_(cd) threshold,the variations in stress and strain and their respective rates of change exhibit a significant increase.The radial deformation and its rate of change exhibit greater sensitivity in response to stress levels.The apparent strain deforms homogeneously at the primary stage,and subsequently,gradually localizes due to the microcrack development at the secondary stage.Ultimately,interconnection of the microcracks causes the formation of a shear-localization zone at the tertiary stage.The strain-time responses inside and outside the localization zone are characterized by local strain accumulation and inelastic unloading during the secondary and tertiary stages,respectively.The width of the shear-localization zone is found to range from 4.43 mm to 7.08 mm and increased with a longer time-to-failure.Scanning electron microscopy(SEM)reveals a dominant coalescence of intergranular cracks on the fracture surface,and the degree of physiochemical deterioration caused by water-rock interaction is more severe under a longer lifetime.The brittle sandstone’s time-dependent deformation is essentially controlled by microcrack development during generalized relaxation,and its expectancy-life is determined by its initial microstructural state and the rheological path. 展开更多
关键词 Generalized relaxation Stress level Direction coefficient Major-strain field Microcrack damage Stress threshold
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Impact of strain relaxation on the growth rate of heteroepitaxial germanium tin binary alloy
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作者 Pedram Jahandar Maksym Myronov 《Journal of Semiconductors》 EI CAS CSCD 2024年第10期35-41,共7页
The growth of high-quality germanium tin(Ge_(1–y)Sn_(y))binary alloys on a Si substrate using chemical vapor deposition(CVD)techniques holds immense potential for advancing electronics and optoelectronics application... The growth of high-quality germanium tin(Ge_(1–y)Sn_(y))binary alloys on a Si substrate using chemical vapor deposition(CVD)techniques holds immense potential for advancing electronics and optoelectronics applications,including the development of efficient and low-cost mid-infrared detectors and light sources.However,achieving precise control over the Sn concentration and strain relaxation of the Ge_(1–y)Sn_(y)epilayer,which directly influence its optical and electrical properties,remain a significant challenge.In this research,the effect of strain relaxation on the growth rate of Ge_(1–y)Sn_(y)epilayers,with Sn concentration>11at.%,is investigated.It is successfully demonstrated that the growth rate slows down by~55%due to strain relaxation after passing its critical thickness,which suggests a reduction in the incorporation of Ge into Ge_(1–y)Sn_(y)growing layers.Despite the increase in Sn concentration as a result of the decrease in the growth rate,it has been found that the Sn incorporation rate into Ge_(1–y)Sn_(y)growing layers has also decreased due to strain relaxation.Such valuable insights could offer a foundation for the development of innovative growth techniques aimed at achieving high-quality Ge_(1–y)Sn_(y)epilayers with tuned Sn concentration and strain relaxation. 展开更多
关键词 GeSn germanium tin strain relaxation groupⅣsemiconductor chemical vapour deposition CVD
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Photosynthetic response dynamics in the invasive species Tithonia diversifolia and two co-occurring native shrub species under fluctuating light conditions
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作者 Ju Li Shu-Bin Zhang Yang-Ping Li 《Plant Diversity》 SCIE CAS CSCD 2024年第2期265-273,共9页
To determine the invasiveness of invasive plants,many studies have compared photosynthetic traits or strategies between invasive and native species.However,few studies have compared the photosynthetic dynamics between... To determine the invasiveness of invasive plants,many studies have compared photosynthetic traits or strategies between invasive and native species.However,few studies have compared the photosynthetic dynamics between invasive and native species during light fluctuations.We compared photosynthetic induction,relaxation dynamics and leaf traits between the invasive species,Tithonia diversifolia and two native species,Clerodendrum bungei and Blumea balsamifera,in full-sun and shady habitats.The photosynthetic dynamics and leaf traits differed among species.T.diversifolia showed a slower induction speed and stomatal opening response but had higher average intrinsic water-use efficiency than the two native species in full-sun habitats.Thus,the slow induction response may be attributed to the longer stomatal length in T.diversifolia.Habitat had a significant effect on photosynthetic dynamics in T.diversifolia and B.balsamifera but not in C.bungei.In shady habitat,T.diversifolia had a faster photosynthetic induction response than in full-sun habitat,leading to a higher average stomatal conductance during photosynthetic induction in T.diversifolia than in the two native species.In contrast,B.balsamifera had a larger stomatal length and slower photosynthetic induction and relaxation response in shady habitat than in full-sun habitat,resulting in higher carbon gain during photosynthetic relaxation.Nevertheless,in both habitats,T.diversifolia had an overall higher carbon gain during light fluctuations than the two native species.Our results indicated that T.diversifolia can adopt more effective response strategies under fluctuating light environments to maximize carbon gain,which may contribute to its successful invasion. 展开更多
关键词 Invasive plant Photosynthetic induction Photosynthetic relaxation Carbon gain Stomatal traits Tithonia diversifolia
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Solid-state impedance spectroscopy studies of dielectric properties and relaxation processes in Na_(2)O–V_(2)O_(5)–Nb_(2)O_(5)–P_(2)O_(5) glass
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作者 Sara Marijan Luka Pavic 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期186-196,共11页
Solid-state impedance spectroscopy(SS-IS)was used to investigate the influence of structural modifications resulting from the addition of Nb2O5 on the dielectric properties and relaxation processes in the quaternary m... Solid-state impedance spectroscopy(SS-IS)was used to investigate the influence of structural modifications resulting from the addition of Nb2O5 on the dielectric properties and relaxation processes in the quaternary mixed glass former(MGF)system 35Na_(2)O–10V_(2)O_(5)–(55-x)P_(2)O_(5)–xNb_(2)O_(5)(x=0–40,mol%).The dielectric parameters,including the dielectric strength and dielectric loss,are determined from the frequency and temperature-dependent complex permittivity data,revealing a significant dependence on the Nb2O5 content.The transition from a predominantly phosphate glass network(x<10,region I)to a mixed niobate–phosphate glass net-work(10≤x≤20,region II)leads to an increase in the dielectric parameters,which correlates with the observed trend in the direct-cur-rent(DC)conductivity.In the predominantly niobate network(x≥25,region III),the highly polarizable nature of Nb5+ions leads to a fur-ther increase in the dielectric permittivity and dielectric strength.This is particularly evident in Nb-40 glass-ceramic,which contains Na_(13)Nb_(35)O_(94) crystalline phase with a tungsten bronze structure and exhibits the highest dielectric permittivity of 61.81 and the lowest loss factor of 0.032 at 303 K and 10 kHz.The relaxation studies,analyzed through modulus formalism and complex impedance data,show that DC conductivity and relaxation processes are governed by the same mechanism,attributed to ionic conductivity.In contrast to glasses with a single peak in frequency dependence of imaginary part of electrical modulus,M″(ω),Nb-40 glass-ceramic exhibits two distinct contributions with similar relaxation times.The high-frequency peak indicates bulk ionic conductivity,while the additional low-fre-quency peak is associated with the grain boundary effect,confirmed by the electrical equivalent circuit(EEC)modelling.The scaling characteristics of permittivity and conductivity spectra,along with the electrical modulus,validate time-temperature superposition and demonstrate a strong correlation with composition and modification of the glass structure upon Nb_(2)O_(5) incorporation. 展开更多
关键词 phosphate glasses GLASS-CERAMICS impedance spectroscopy dielectric properties relaxation processes permittivity scaling conductivity scaling modulus formalism
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Reinforced SnO_(2) tensile-strength and“buffer-spring”interfaces for efficient inorganic perovskite solar cells
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作者 Yuanyuan Zhao Lei Gao +6 位作者 Qiurui Wang Qiang Zhang Xiya Yang Jingwei Zhu Hao Huang Jialong Duan Qunwei Tang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第6期282-291,共10页
Suppressing nonradiative recombination and releasing residual strain areprerequisites to improving the efficiency and stability of perovskite solar cells(PSCs).Here,long-chain polyacrylic acid(PAA)is used to reinforce... Suppressing nonradiative recombination and releasing residual strain areprerequisites to improving the efficiency and stability of perovskite solar cells(PSCs).Here,long-chain polyacrylic acid(PAA)is used to reinforce SnO_(2)film and passivate SnO_(2)defects,forming a structure similar to“reinforcedconcrete”with high tensile strength and fewer microcracks.Simultaneously,PAA is also introduced to the SnO_(2)/perovskite interface as a“buffer spring”torelease residual strain,which also acts as a“dual-side passivation interlayer”to passivate the oxygen vacancies of SnO_(2)and Pb dangling bonds in halideperovskites.As a result,the best inorganic CsPbBr_(3)PSC achieves a championpower conversion efficiency of 10.83%with an ultrahigh open-circuit voltageof 1.674 V.The unencapsulated PSC shows excellent stability under 80%relative humidity and 80℃over 120 days. 展开更多
关键词 charge recombination defect passivation inorganic perovskite solar cells interfacial modification strain relaxation
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Improved Twin Support Vector Machine Algorithm and Applications in Classification Problems
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作者 Sun Yi Wang Zhouyang 《China Communications》 SCIE CSCD 2024年第5期261-279,共19页
The distribution of data has a significant impact on the results of classification.When the distribution of one class is insignificant compared to the distribution of another class,data imbalance occurs.This will resu... The distribution of data has a significant impact on the results of classification.When the distribution of one class is insignificant compared to the distribution of another class,data imbalance occurs.This will result in rising outlier values and noise.Therefore,the speed and performance of classification could be greatly affected.Given the above problems,this paper starts with the motivation and mathematical representing of classification,puts forward a new classification method based on the relationship between different classification formulations.Combined with the vector characteristics of the actual problem and the choice of matrix characteristics,we firstly analyze the orderly regression to introduce slack variables to solve the constraint problem of the lone point.Then we introduce the fuzzy factors to solve the problem of the gap between the isolated points on the basis of the support vector machine.We introduce the cost control to solve the problem of sample skew.Finally,based on the bi-boundary support vector machine,a twostep weight setting twin classifier is constructed.This can help to identify multitasks with feature-selected patterns without the need for additional optimizers,which solves the problem of large-scale classification that can’t deal effectively with the very low category distribution gap. 展开更多
关键词 FUZZY ordered regression(OR) relaxing variables twin support vector machine
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