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Light-stimulated adaptive artificial synapse based on nanocrystalline metal-oxide film
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作者 Igor S.Balashov Alexander A.Chezhegov +3 位作者 Artem S.Chizhov Andrey A.Grunin Konstantin V.Anokhin Andrey A.Fedyanin 《Opto-Electronic Science》 2023年第10期1-11,共11页
Artificial synapses utilizing spike signals are essential elements of new generation brain-inspired computers.In this paper,we realize light-stimulated adaptive artificial synapse based on nanocrystalline zinc oxide f... Artificial synapses utilizing spike signals are essential elements of new generation brain-inspired computers.In this paper,we realize light-stimulated adaptive artificial synapse based on nanocrystalline zinc oxide film.The artificial synapse photoconductivity shows spike-type signal response,long and short-term memory(LTM and STM),STM-to-LTM transition and paired-pulse facilitation.It is also retaining the memory of previous exposures and demonstrates spike-frequency adaptation properties.A way to implement neurons with synaptic depression,tonic excitation,and delayed accelerating types of response under the influence of repetitive light signals is discussed.The developed artificial synapse is able to become a key element of neuromorphic chips and neuromorphic sensorics systems. 展开更多
关键词 neuromorphic photonics synaptic adaptation spiking neuron neuromorphic computing optoelectronic synaptic devises nanocrystalline metal-oxide film
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Cardiac arrest, stony heart, and cardiopulmonary resuscitation: An updated revisit
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作者 Ayman El-Menyar Bianca M Wahlen 《World Journal of Cardiology》 2024年第3期126-136,共11页
The post-resuscitation period is recognized as the main predictor of cardiopul-monary resuscitation(CPR)outcomes.The first description of post-resuscitation syndrome and stony heart was published over 50 years ago.Maj... The post-resuscitation period is recognized as the main predictor of cardiopul-monary resuscitation(CPR)outcomes.The first description of post-resuscitation syndrome and stony heart was published over 50 years ago.Major manifestations may include but are not limited to,persistent precipitating pathology,systemic ischemia/reperfusion response,post-cardiac arrest brain injury,and finally,post-cardiac arrest myocardial dysfunction(PAMD)after successful resuscitation.Why do some patients initially survive successful resuscitation,and others do not?Also,why does the myocardium response vary after resuscitation?These ques-tions have kept scientists busy for several decades since the first successful resuscitation was described.By modifying the conventional modalities of resu-scitation together with new promising agents,rescuers will be able to salvage the jeopardized post-resuscitation myocardium and prevent its progression to a dismal,stony heart.Community awareness and staff education are crucial for shortening the resuscitation time and improving short-and long-term outcomes.Awareness of these components before and early after the restoration of circulation will enhance the resuscitation outcomes.This review extensively addresses the underlying pathophysiology,management,and outcomes of post-resuscitation syndrome.The pattern,management,and outcome of PAMD and post-cardiac arrest shock are different based on many factors,including in-hospital cardiac arrest vs out-of-hospital cardiac arrest(OHCA),witnessed vs unwitnessed cardiac arrest,the underlying cause of arrest,the duration,and protocol used for CPR.Although restoring spontaneous circulation is a vital sign,it should not be the end of the game or lone primary outcome;it calls for better understanding and aggressive multi-disciplinary interventions and care.The development of stony heart post-CPR and OHCA remain the main challenges in emergency and critical care medicine. 展开更多
关键词 Cardiac arrest Out-of-hospital cardiac arrest In-hospital cardiac arrest Post-resuscitation Myocardial dysfunction Cardiopulmonary resuscitation Stony heart
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Glucose metabolic reprogramming-related parameters for the prediction of 28-day neurological prognosis and all-cause mortality in patients after cardiac arrest:a prospective single-center observational study
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作者 Subi Abudurexiti Shihai Xu +2 位作者 Zhangping Sun Yi Jiang Ping Gong 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第3期197-205,共9页
BACKGROUND:We aimed to observe the dynamic changes in glucose metabolic reprogrammingrelated parameters and their ability to predict neurological prognosis and all-cause mortality in cardiac arrest patients after the ... BACKGROUND:We aimed to observe the dynamic changes in glucose metabolic reprogrammingrelated parameters and their ability to predict neurological prognosis and all-cause mortality in cardiac arrest patients after the restoration of spontaneous circulation(ROSC).METHODS:Adult cardiac arrest patients after ROSC who were admitted to the emergency or cardiac intensive care unit of the First Aflliated Hospital of Dalian Medical University from August 1,2017,to May 30,2021,were enrolled.According to 28-day survival,the patients were divided into a non-survival group(n=82) and a survival group(n=38).Healthy adult volunteers(n=40) of similar ages and sexes were selected as controls.The serum levels of glucose metabolic reprogrammingrelated parameters(lactate dehydrogenase [LDH],lactate and pyruvate),neuron-specific enolase(NSE) and interleukin 6(IL-6) were measured on days 1,3,and 7 after ROSC.The Acute Physiology and Chronic Health Evaluation II(APACHE II) score and Sequential Organ Failure Assessment(SOFA) score were calculated.The Cerebral Performance Category(CPC) score was recorded on day 28 after ROSC.RESULTS:Following ROSC,the serum LDH(607.0 U/L vs.286.5 U/L),lactate(5.0 mmol/L vs.2.0 mmol/L),pyruvate(178.0 μmol/L vs.70.9 μmol/L),and lactate/pyruvate ratio(34.1 vs.22.1) significantly increased and were higher in the non-survivors than in the survivors on admission(all P<0.05).Moreover,the serum LDH,pyruvate,IL-6,APACHE II score,and SOFA score on days 1,3 and 7 after ROSC were significantly associated with 28-day poor neurological prognosis and 28-day all-cause mortality(all P<0.05).The serum LDH concentration on day 1 after ROSC had an area under the receiver operating characteristic curve(AUC) of 0.904 [95% confidence interval [95% CI]:0.851–0.957]) with 96.8% specificity for predicting 28-day neurological prognosis and an AUC of 0.950(95% CI:0.911–0.989) with 94.7% specificity for predicting 28-day all-cause mortality,which was the highest among the glucose metabolic reprogramming-related parameters tested.CONCLUSION:Serum parameters related to glucose metabolic reprogramming were significantly increased after ROSC.Increased serum LDH and pyruvate levels,and lactate/pyruvate ratio may be associated with 28-day poor neurological prognosis and all-cause mortality after ROSC,and the predictive eflcacy of LDH during the first week was superior to others. 展开更多
关键词 Glucose metabolic reprogramming Lactate dehydrogenase Cardiac arrest PROGNOSIS
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Antitumor Effect of Apcin on Endometrial Carcinoma via p21-Mediated Cell Cycle Arrest and Apoptosis
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作者 Ke NI Zi-li LI +1 位作者 Zhi-yong HU Li HONG 《Current Medical Science》 SCIE CAS 2024年第3期623-632,共10页
Objective Endometrial carcinoma(EC)is a prevalent gynecological malignancy characterized by increasing incidence and mortality rates.This underscores the critical need for novel therapeutic targets.One such potential ... Objective Endometrial carcinoma(EC)is a prevalent gynecological malignancy characterized by increasing incidence and mortality rates.This underscores the critical need for novel therapeutic targets.One such potential target is cell division cycle 20(CDC20),which has been implicated in oncogenesis.This study investigated the effect of the CDC20 inhibitor Apcin on EC and elucidated the underlying mechanism involved.Methods The effects of Apcin on EC cell proliferation,apoptosis,and the cell cycle were evaluated using CCK8 assays and flow cytometry.RNA sequencing(RNA-seq)was subsequently conducted to explore the underlying molecular mechanism,and Western blotting and coimmunoprecipitation were subsequently performed to validate the results.Animal studies were performed to evaluate the antitumor effects in vivo.Bioinformatics analysis was also conducted to identify CDC20 as a potential therapeutic target in EC.Results Treatment with Apcin inhibited proliferation and induced apoptosis in EC cells,resulting in cell cycle arrest.Pathways associated with apoptosis and the cell cycle were activated following treatment with Apcin.Notably,Apcin treatment led to the upregulation of the cell cycle regulator p21,which was verified to interact with CDC20 and consequently decrease the expression of downstream cyclins in EC cells.In vivo experiments confirmed that Apcin treatment significantly impeded tumor growth.Higher CDC20 expression was observed in EC tissue than in nonmalignant tissue,and increased CDC20 expression in EC patients was associated with shorter overall survival and progress free interval.Conclusion CDC20 is a novel molecular target in EC,and Apcin could be developed as a candidate antitumor drug for EC treatment. 展开更多
关键词 endometrial carcinoma CDC20 APOPTOSIS cell cycle arrest P21 BBC3
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Critical Solvation Structures Arrested Active Molecules for Reversible Zn Electrochemistry
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作者 Junjie Zheng Bao Zhang +14 位作者 Xin Chen Wenyu Hao Jia Yao Jingying Li Yi Gan Xiaofang Wang Xingtai Liu Ziang Wu Youwei Liu Lin Lv Li Tao Pei Liang Xiao Ji Hao Wang Houzhao Wan 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期64-78,共15页
Aqueous Zn-ion batteries(AZIBs)have attracted increasing attention in next-generation energy storage systems due to their high safety and economic.Unfortunately,the side reactions,dendrites and hydrogen evolution effe... Aqueous Zn-ion batteries(AZIBs)have attracted increasing attention in next-generation energy storage systems due to their high safety and economic.Unfortunately,the side reactions,dendrites and hydrogen evolution effects at the zinc anode interface in aqueous electrolytes seriously hinder the application of aqueous zinc-ion batteries.Here,we report a critical solvation strategy to achieve reversible zinc electrochemistry by introducing a small polar molecule acetonitrile to form a“catcher”to arrest active molecules(bound water molecules).The stable solvation structure of[Zn(H_(2)O)_(6)]^(2+)is capable of maintaining and completely inhibiting free water molecules.When[Zn(H_(2)O)_(6)]^(2+)is partially desolvated in the Helmholtz outer layer,the separated active molecules will be arrested by the“catcher”formed by the strong hydrogen bond N-H bond,ensuring the stable desolvation of Zn^(2+).The Zn||Zn symmetric battery can stably cycle for 2250 h at 1 mAh cm^(-2),Zn||V_(6)O_(13) full battery achieved a capacity retention rate of 99.2%after 10,000 cycles at 10 A g^(-1).This paper proposes a novel critical solvation strategy that paves the route for the construction of high-performance AZIBs. 展开更多
关键词 Zinc-ion battery Critical solvation Helmholtz layer arrest active molecule Reversible zinc anode
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Hydrangea serrata extract exerts tumor inhibitory activity against hepatocellular carcinoma HepG2 cells via inducing p27/CDK2-mediated cell cycle arrest and apoptosis
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作者 Ye-eun Kim Jeonghye Hwang Ki-Young Kim 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第2期65-72,I0002-I0005,共12页
Objective:To examine the inhibitory effect of Hydrangea serrata extract against hepatocellular carcinoma HepG2 cells and its underlying mechanisms.Methods:The effects of Hydrangea serrata extract on growth inhibition ... Objective:To examine the inhibitory effect of Hydrangea serrata extract against hepatocellular carcinoma HepG2 cells and its underlying mechanisms.Methods:The effects of Hydrangea serrata extract on growth inhibition of tumor cells and spheroids were assessed using MTT and 3D culture assays.Quantitative real-time PCR and Western blot analyses were employed to investigate the changes in mRNA and protein expression levels of molecules related to cell cycle and apoptosis.Results:Hydrangea serrata extract effectively inhibited the growth of both tumor cells and spheroids.The extract also significantly upregulated p27 mRNA expression and downregulated CDK2 mRNA expression,leading to cell cycle arrest.Moreover,increased BAX/Bcl-2 ratio as well as caspase-9 and-3 were observed after treatment with Hydrangea serrata extract,indicating the induction of tumor cell apoptosis.Conclusions:Hydrangea serrata extract has the potential to alleviate tumors by effectively modulating cell-cycle-related gene expressions and inducing apoptosis,thereby inhibiting tumor growth. 展开更多
关键词 Hydrangea serrata Hepatocellular carcinoma Liver cancer Anticancer Cell cycle arrest APOPTOSIS
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Approach to traumatic cardiac arrest in the emergency department: a narrative literature review for emergency providers
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作者 Rashed Alremeithi Quincy K.Tran +2 位作者 Megan T.Quintana Soroush Shahamatdar Ali Pourmand 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第1期3-9,共7页
BACKGROUND:Traumatic cardiac arrest(TCA)is a major contributor to mortality and morbidity in all age groups and poses a significant burden on the healthcare system.Although there have been advances in treatment modali... BACKGROUND:Traumatic cardiac arrest(TCA)is a major contributor to mortality and morbidity in all age groups and poses a significant burden on the healthcare system.Although there have been advances in treatment modalities,survival rates for TCA patients remain low.This narrative literature review critically examines the indications and eff ectiveness of current therapeutic approaches in treating TCA.METHODS:We performed a literature search in the PubMed and Scopus databases for studies published before December 31,2022.The search was refi ned by combining search terms,examining relevant study references,and restricting publications to the English language.Following the search,943 articles were retrieved,and two independent reviewers conducted a screening process.RESULTS:A review of various studies on pre-and intra-arrest prognostic factors showed that survival rates were higher when patients had an initial shockable rhythm.There were conflicting results regarding other prognostic factors,such as witnessed arrest,bystander cardiopulmonary resuscitation(CPR),and the use of prehospital or in-hospital epinephrine.Emergency thoracotomy was found to result in more favorable outcomes in cases of penetrating trauma than in those with blunt trauma.Resuscitative endovascular balloon occlusion of the aorta(REBOA)provides an advantage to emergency thoracotomy in terms of occupational safety for the operator as an alternative in managing hemorrhagic shock.When implemented in the setting of aortic occlusion,emergency thoracotomy and REBOA resulted in comparable mortality rates.Veno-venous extracorporeal life support(V-V ECLS)and veno-arterial extracorporeal life support(V-A ECLS)are viable options for treating respiratory failure and cardiogenic shock,respectively.In the context of traumatic injuries,V-V ECLS has been associated with higher rates of survival to discharge than V-A ECLS.CONCLUSION:TCA remains a signifi cant challenge for emergency medical services due to its high morbidity and mortality rates.Pre-and intra-arrest prognostic factors can help identify patients who are likely to benefit from aggressive and resource-intensive resuscitation measures.Further research is needed to enhance guidelines for the clinical use of established and emerging therapeutic approaches that can help optimize treatment effi cacy and ameliorate survival outcomes. 展开更多
关键词 Traumatic cardiac arrest Emergency thoracotomy Resuscitative endovascular balloon occlusion of the aorta
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Recovering from prolonged cardiac arrest induced by electric shock:A case report
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作者 Jian Zhang Yan-Ru Qiao +2 位作者 Ya-Dong Yang Guo-Zheng Pan Chong-Qing Lv 《World Journal of Clinical Cases》 SCIE 2024年第13期2248-2253,共6页
BACKGROUND Cardiac arrest(CA)induced by electric shock is a rare occurrence,particularly in cases of prolonged CA.Currently,there is limited literature on similar incidents,and we present a relevant case report.CASE S... BACKGROUND Cardiac arrest(CA)induced by electric shock is a rare occurrence,particularly in cases of prolonged CA.Currently,there is limited literature on similar incidents,and we present a relevant case report.CASE SUMMARY A 27-year-old Asian male man,experiencing respiratory CA due to electric shock,was successfully restored to sinus rhythm after 50 min of cardiopulmonary resuscitation and 8 electrical defibrillation sessions.In the subsequent stages,the patient received multiple organ function protection measures,leading to a successful recovery and eventual discharge from the hospital.CONCLUSION Prolonging resuscitation time can enhance the chances of survival for patients,this study provide valuable insights into the management of electric shock-induced CA. 展开更多
关键词 Electric shock Cardiac arrest Prolonged cardiopulmonary resuscitation Cerebral resuscitation Case report
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A novel predictor of unsustained return of spontaneous circulation in cardiac arrest patients through a combination of capnography and pulse oximetry: a multicenter observational study
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作者 Jing Yang Hanqi Tang +11 位作者 Shihuan Shao Feng Xu Yangyang Fu Shengyong Xu Chen Li Yan Li Yang Liu Joseph Harold Walline Huadong Zhu Yuguo Chen Xuezhong Yu Jun Xu 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第1期16-22,共7页
BACKGROUND:Unsustained return of spontaneous circulation(ROSC)is a critical barrier to survival in cardiac arrest patients.This study examined whether end-tidal carbon dioxide(ETCO_(2))and pulse oximetry photoplethysm... BACKGROUND:Unsustained return of spontaneous circulation(ROSC)is a critical barrier to survival in cardiac arrest patients.This study examined whether end-tidal carbon dioxide(ETCO_(2))and pulse oximetry photoplethysmogram(POP)parameters can be used to identify unsustained ROSC.METHODS:We conducted a multicenter observational prospective cohort study of consecutive patients with cardiac arrest from 2013 to 2014.Patients’general information,ETCO_(2),and POP parameters were collected and statistically analyzed.RESULTS:The included 105 ROSC episodes(from 80 cardiac arrest patients)comprised 51 sustained ROSC episodes and 54 unsustained ROSC episodes.The 24-hour survival rate was significantly higher in the sustained ROSC group than in the unsustained ROSC group(29.2%vs.9.4%,P<0.05).The logistic regression analysis showed that the difference between after and before ROSC in ETCO_(2)(ΔETCO_(2))and the difference between after and before ROCS in area under the curve of POP(ΔAUCp)were independently associated with sustained ROSC(odds ratio[OR]=0.931,95%confi dence interval[95%CI]0.881-0.984,P=0.011 and OR=0.998,95%CI 0.997-0.999,P<0.001).The area under the receiver operating characteristic curve ofΔETCO_(2),ΔAUCp,and the combination of both to predict unsustained ROSC were 0.752(95%CI 0.660-0.844),0.883(95%CI 0.818-0.948),and 0.902(95%CI 0.842-0.962),respectively.CONCLUSION:Patients with unsustained ROSC have a poor prognosis.The combination ofΔETCO_(2) andΔAUCp showed signifi cant predictive value for unsustained ROSC. 展开更多
关键词 Return of spontaneous circulation Pulse oximetry photoplethysmogram End-tidal carbon dioxide Cardiac arrest Cardiopulmonary resuscitation
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Correction:Establishment of a prediction model for prehospital return of spontaneous circulation in out-of-hospital patients with cardiac arrest
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作者 Jing-Jing Wang Qiang Zhou +5 位作者 Zhen-Hua Huang Yong Han Chong-Zhen Qin Zhong-Qing Chen Xiao-Yong Xiao Zhe Deng 《World Journal of Cardiology》 2024年第4期215-216,共2页
This is an erratum to an already published paper named“Establishment of a prediction model for prehospital return of spontaneous circulation in out-ofhospital patients with cardiac arrest”.We found errors in the aff... This is an erratum to an already published paper named“Establishment of a prediction model for prehospital return of spontaneous circulation in out-ofhospital patients with cardiac arrest”.We found errors in the affiliated institution of the authors.We apologize for our unintentional mistake.Please note,these changes do not affect our results. 展开更多
关键词 Cardiac arrest Cardiopulmonary resuscitation Recovery spontaneous circulation Logistic regression analysis Predictive model
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Hypoxia-preconditioned bone marrow-derived mesenchymal stem cells protect neurons from cardiac arrest-induced pyroptosis
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作者 Xiahong Tang Nan Zheng +8 位作者 Qingming Lin Yan You Zheng Gong Yangping Zhuang Jiali Wu Yu Wang Hanlin Huang Jun Ke Feng Chen 《Neural Regeneration Research》 SCIE CAS 2025年第4期1103-1123,共21页
Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological damage.Hypoxic preconditioning has been shown to impr... Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological damage.Hypoxic preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are unknown.To this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB pathways.Subsequently,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by asphyxia.The results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these effects.To conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning. 展开更多
关键词 bone marrow–derived mesenchymal stem cells cardiac arrest cardiac resuscitation hypoxic preconditioning liver isoform of phosphofructokinase mitochondria NEUROINFLAMMATION oxidative stress PYROPTOSIS reactive oxygen species
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High-voltage super-junction lateral double-diffused metal-oxide semiconductor with a partial lightly doped pillar 被引量:3
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作者 伍伟 张波 +2 位作者 方健 罗小蓉 李肇基 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第6期633-636,共4页
A novel super-junction lateral double-diffused metal-oxide semiconductor (SJ-LDMOS) with a partial lightly doped P pillar (PD) is proposed. Firstly, the reduction in the partial P pillar charges ensures the charge... A novel super-junction lateral double-diffused metal-oxide semiconductor (SJ-LDMOS) with a partial lightly doped P pillar (PD) is proposed. Firstly, the reduction in the partial P pillar charges ensures the charge balance and suppresses the substrate-assisted depletion effect. Secondly, the new electric field peak produced by the P/P junction modulates the surface electric field distribution. Both of these result in a high breakdown voltage (BV). In addition, due to the same conduction paths, the specific on-resistance (Ron,sp) of the PD SJ-LDMOS is approximately identical to the conventional SJ-LDMOS. Simulation results indicate that the average value of the surface lateral electric field of the PD SJ-LDMOS reaches 20 V/μm at a 15 μm drift length, resulting in a BV of 300 V. 展开更多
关键词 super-junction lateral double-diffused metal-oxide semiconductor partial lightly doped pillar electric field modulation breakdown voltage
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Wet thermal annealing effect on TaN/HfO_2/Ge metal-oxide-semiconductor capacitors with and without a GeO_2 passivation layer 被引量:3
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作者 刘冠洲 李成 +7 位作者 路长宝 唐锐钒 汤梦饶 吴政 杨旭 黄巍 赖虹凯 陈松岩 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第11期467-473,共7页
Wet thermal annealing effects on the properties of TaN/HfO2/Ge metal-oxide-semiconductor (MOS) structures with and without a GeO2 passivation layer are investigated. The physical and the electrical properties are ch... Wet thermal annealing effects on the properties of TaN/HfO2/Ge metal-oxide-semiconductor (MOS) structures with and without a GeO2 passivation layer are investigated. The physical and the electrical properties are characterized by X-ray photoemission spectroscopy, high-resolution transmission electron microscopy, capacitance-voltage (C-V) and current-voltage characteristics. It is demonstrated that wet thermal annealing at relatively higher temperature such as 550 ℃ can lead to Ge incorporation in HfO2 and the partial crystallization of HfO2, which should be responsible for the serious degradation of the electrical characteristics of the TaN/HfO2/Ge MOS capacitors. However, wet thermal annealing at 400 ℃ can decrease the GeOx interlayer thickness at the HfO2/Ge interface, resulting in a significant reduction of the interface states and a smaller effective oxide thickness, along with the introduction of a positive charge in the dielectrics due to the hydrolyzable property of GeOx in the wet ambient. The pre-growth of a thin GeO2 passivation layer can effectively suppress the interface states and improve the C V characteristics for the as-prepared HfO2 gated Ge MOS capacitors, but it also dissembles the benefits of wet thermal annealing to a certain extent. 展开更多
关键词 HfO2 dielectric on germanium X-ray photoemission spectroscopy wet thermal anneal-ing metal-oxide semiconductor capacitor
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Reconstruction model for temperature and concentration profiles of soot and metal-oxide nanoparticles in a nanofluid fuel flame by using a CCD camera 被引量:2
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作者 刘冠楠 刘冬 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第5期334-343,共10页
This paper presents a numerical study on the simultaneous reconstruction of temperature and volume fraction fields of soot and metal-oxide nanoparticles in an axisymmetric nanofluid fuel sooting flame based on the rad... This paper presents a numerical study on the simultaneous reconstruction of temperature and volume fraction fields of soot and metal-oxide nanoparticles in an axisymmetric nanofluid fuel sooting flame based on the radiative energy images captured by a charge-coupled device(CCD) camera. The least squares QR decomposition method was introduced to deal with the reconstruction inverse problem. The effects of ray numbers and measurement errors on the reconstruction accuracy were investigated. It was found that the reconstruction accuracies for volume fraction fields of soot and metaloxide nanoparticles were easily affected by the measurement errors for radiation intensity, whereas only the metal-oxide volume fraction field reconstruction was more sensitive to the measurement error for the volume fraction ratio of metaloxide nanoparticles to soot. The results show that the temperature, soot volume fraction, and metal-oxide nanoparticles volume fraction fields can be simultaneously and accurately retrieved for exact and noisy data using a single CCD camera. 展开更多
关键词 simultaneous reconstruction temperature distribution soot and metal-oxide volume fraction nanofluid fuel flame
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Tuning the Electrochemical Property of the Ultrafine Metal-oxide Nanoclusters by Iron Phthalocyanine as Efficient Catalysts for Energy Storage and Conversion 被引量:3
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作者 Yi Cheng Xing Wu +3 位作者 Jean-Pierre Veder Lars Thomsen San Ping Jiang Shuangyin Wang 《Energy & Environmental Materials》 2019年第1期5-17,共13页
Nanoclusters(NCs)have been demonstrated of outstanding performance in electrochemical energy storage and conversion technologies due to their strong quantum confinement effects and strong interaction with supports.Her... Nanoclusters(NCs)have been demonstrated of outstanding performance in electrochemical energy storage and conversion technologies due to their strong quantum confinement effects and strong interaction with supports.Here,we developed a class of ultrafine metal-oxide(MOx,M=Fe,Co and Ni)NCs incorporated with iron phthalocyanine(FePc),MOx/FePc-G,supported on graphene as high-performance catalysts for oxygen reduction reaction(ORR),oxygen evolution reaction(OER),and carbon dioxide reduction(CO2RR).The high activities for ORR and OER are attributed to the electron donation and accepting ability of the highly redox active of FePc-G that could tune the properties of MOx.The FeOx/FePc-G exhibits an extremely positive half-wave potential(E1/2)of 0.888 and 0.610 V for ORR in alkaline and neutral conditions,respectively,which is around 60 mV more positive than that of Pt/C.And NiOx/FePc-G shows similar OER activity with the state-of-the-art catalysts,Ir/C,and better performance than NiFeO NCs supported on graphene.Remarkably,the CoOx/FePc-G and NiOx/FePc-G show high activity and selectivity to reduce CO2 into CO with a low onset potential of-0.22 V(overpotential is 0.11 V). 展开更多
关键词 CO2 reduction reaction iron phthalocyanine metal-oxide nanoclusters oxygen evolution reaction oxygen reduction reaction
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Study of the Electric Filed Around a Metal Oxide Surge Arrester: Measurement and Simulation 被引量:5
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作者 Christodoulou C A Spanias C A Kontargyri V T Gonos I F Stathopulos I A 《高电压技术》 EI CAS CSCD 北大核心 2013年第8期2014-2021,共8页
The study of the electric field around a surge arrester is useful for design procedures and diagnostic tests. The current work com- putes the electric field around a medium voltage gapless surge arrester using 2D and ... The study of the electric field around a surge arrester is useful for design procedures and diagnostic tests. The current work com- putes the electric field around a medium voltage gapless surge arrester using 2D and 3D representation of the arrester. The 2D simulation design, which is described in IEC 60099-4 Standard, cannot include the non symmetrical parts of the arrester geometry and the test arrange- ment. 3D simulation procedures have the advantage that takes into account these asymmetries, giving more accurate results for each measurement position. In order to confirm the suitability of the created models, the simulation results of the electric field, using the 2D and 3D edition of PC Opera, are compared with recorded measurements, which are obtained in laboratory using appropriate calibrated field meters. 展开更多
关键词 金属氧化物避雷器 测量位置 仿真设计 电动 诊断测试 模拟程序 设计程序 不对称性
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Leakage Currents of Zinc Oxide Surge Arresters in 22 kV Distribution System Using Thermal Image Camera
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作者 Wichet Thipprasert Prakasit Sritakaew 《Journal of Power and Energy Engineering》 2014年第4期712-717,共6页
Zinc Oxide (ZnO) surge arresters (SAs) experience thermal runaway when the temperature exceeds the acceptable limit. This phenomenon is associated with the increase in resistive leakage current due to degradation. Thi... Zinc Oxide (ZnO) surge arresters (SAs) experience thermal runaway when the temperature exceeds the acceptable limit. This phenomenon is associated with the increase in resistive leakage current due to degradation. This paper presents the electrical performance of ZnO SAs in 22 kV distribution systems using thermal image camera under the power frequency AC operating voltages. When ZnO surge arresters are installation takes a long time in distribution system over more than 5 years. For the experimental study, as ZnO installation takes a long time over 6 years the leakage current is 63.9 mA, temperature differences were measured over a period of time over 14 degree Celsius. This data will be useful as a guideline for solving problems and reducing power loss from leakage current. Moreover, it will be useful in predicting lifetime of ZnO SAs. 展开更多
关键词 Electrical Performance SURGE arrester Thermal Image CAMERA
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The neuro-prognostic value of the ion shift index in cardiac arrest patients following extracorporeal cardiopulmonary resuscitation 被引量:1
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作者 Gannan Wang Zhe Wang +4 位作者 Yi Zhu Zhongman Zhang Wei Li Xufeng Chen Yong Mei 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2023年第5期354-359,共6页
BACKGROUND:The ion shift index(ISI) as a prognostic indicator that can show the severity of hypoxic-ischemic injury.We aimed to evaluate the performance of the ISI in predicting unfavorable neurological outcomes at ho... BACKGROUND:The ion shift index(ISI) as a prognostic indicator that can show the severity of hypoxic-ischemic injury.We aimed to evaluate the performance of the ISI in predicting unfavorable neurological outcomes at hospital discharge in cardiac arrest(CA) patients following extracorporeal cardiopulmonary resuscitation(ECPR) and to compare its performance to other prognostic predictors.METHODS:This was a retrospective observational study including adult CA patients treated with ECPR between January 2018 and December 2022 in a tertiary hospital.Data regarding clinical characteristics and laboratory parameters were collected from medical records.The ISI was determined based on the first available serum electrolyte levels after ECPR.The primary outcome was unfavorable neurological status at hospital discharge,defined as Cerebral Performance Categories 3–5.Comparisons of the characteristics between the two groups were made using the χ2 test for categorical variables and the t-test or non-parametric Mann-Whitney U-test for continuous variables,as appropriate.Correlation analysis was performed using Spearman’s rank correlation coeficient.A two-tailed P-value <0.05 was considered statistically significant.RESULTS:Among the 122 patients involved,46(37.7%) had out-of-hospital CA,and 88 had unfavorable neurological outcomes.The ISI was significantly higher in the unfavorable outcome group than in the favorable outcome group(3.74 [3.15–4.57] vs.2.69 [2.51–3.07],P<0.001).A higher ISI level was independently related to unfavorable outcome(odds ratio=6.529,95% confidence interval 2.239–19.044,P=0.001).An ISI level >3.12 predicted unfavorable outcomes with a sensitivity and specificity of 74.6% and 85.2%,respectively(P<0.001).The prognostic performance of ISI(area under the curve [AUC]=0.887) was similar to that of other predictors,such as gray-to-white matter ratio(AUC=0.850,P=0.433) and neuronspecific enolase(AUC=0.925,P=0.394).CONCLUSION:ISI may be used as a prognostic biomarker to predict neurological outcomes in CA patients following ECPR. 展开更多
关键词 Cardiac arrest Ion shift index Extracorporeal cardiopulmonary resuscitation
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An integrated model for predicting the flame propagation in crimped ribbon flame arresters 被引量:1
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作者 Zheng Wang Bing Sun +1 位作者 Qingshan Huang Fuhua Jiang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第5期930-941,共12页
Crimped ribbon flame arresters are important safety devices in the chemical industry, especially for the dangerous situations. Although proper design of arresters by the numerical simulation method is promising, its r... Crimped ribbon flame arresters are important safety devices in the chemical industry, especially for the dangerous situations. Although proper design of arresters by the numerical simulation method is promising, its reliability and accuracy are dependent upon the mathematical model. In this work, an integrated mathematical model for the microchannel in the crimped ribbon flame arresters was set up; the fluid flow behavior and the sensitivities of four chemical kinetics mechanisms of propane-air on the accuracy were analysed. It is shown that turbulence is predominant in the microchannel of the crimped ribbon flame arresters under the deflagration and detonation conditions, and a new quenching criterion for the numerical simulation is proposed. The kinetics mechanism of Mansouri et al. among the four ones is the most accurate due to the best agreement of the predicted outlet temperature at the experimental flameproof velocity with the autoignition temperature of propane-air. The species mass fraction profiles and the temperature distribution, which are too difficult to measure due to the tiny dimension of the microchannel in experiments, are captured. The fundamental insights into chemical reactions and heat loss are well portrayed. It can be concluded that the integrated mathematical model established in this work can be used as a reliable tool for modeling, selecting and designing such type of crimped ribbon flame arresters with the propane-air medium in the future. 展开更多
关键词 火焰 带子 综合模型 综合数学模型 数字模拟方法 动力学机制 繁殖 预言
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Effect of metal oxide arrester on the chaotic oscillations in the voltage transformer with nonlinear core loss model using chaos theory
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《Chinese Physics B》 SCIE EI CAS CSCD 2014年第1期480-488,共9页
In this paper, controlling chaos when chaotic ferroresonant oscillations occur in a voltage transformer with nonlin- ear core loss model is performed. The effect of a parallel metal oxide surge arrester on the ferrore... In this paper, controlling chaos when chaotic ferroresonant oscillations occur in a voltage transformer with nonlin- ear core loss model is performed. The effect of a parallel metal oxide surge arrester on the ferroresonance oscillations of voltage transformers is studied. The metal oxide arrester (MOA) is found to be effective in reducing ferroresonance chaotic oscillations. Also the multiple scales method is used to analyze the chaotic behavior and different types of fixed points in ferroresonance of voltage transformers considering core loss. This phenomenon has nonlinear chaotic dynamics and includes sub-harmonic, quasi-periodic, and also chaotic oscillations. In this paper, the chaotic behavior and various ferroresonant oscillation modes of the voltage transformer is studied. This phenomenon consists of different types of bifur- cations such as period doubling bifurcation (PDB), saddle node bifurcation (SNB), Hopf bifurcation (HB), and chaos. The dynamic analysis of ferroresonant circuit is based on bifurcation theory. The bifurcation and phase plane diagrams are il- lustrated using a continuous method and linear and nonlinear models of core loss. To analyze ferroresonance phenomenon, the Lyapunov exponents are calculated via the multiple scales method to obtain Feigenbaum numbers. The bifurcation diagrams illustrate the variation of the control parameter. Therefore, the chaos is created and increased in the system. 展开更多
关键词 FERRORESONANCE chaos theory metal oxide arrester Lyapunov exponent
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