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Rechargeable solid-state Li-air batteries: a status report 被引量:8
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作者 Chu-Shu Yang KangNing Gao +2 位作者 XiaoPing Zhang Zhuang Sun Tao Zhang 《Rare Metals》 SCIE EI CAS CSCD 2018年第6期459-472,共14页
The theoretical specific energy of lithium-air battery is as high as 3436 Wh.kg^-1, and the possible achieved value may reach 600-700 Wh.kg^-l, which enables this energy storage system as an important propulsion power... The theoretical specific energy of lithium-air battery is as high as 3436 Wh.kg^-1, and the possible achieved value may reach 600-700 Wh.kg^-l, which enables this energy storage system as an important propulsion power sources for electric vehicles with the driving range of 500-800 km. Currently, Li-air batteries are facing main challenges at stability, efficiency, applicability and safety. In particular, from a practical view of point, the Li-air batteries should be operated directly in ambient air. Solid-state battery system is the best avenue to eventually solve these main issues. At the heart of the solid state, Li-air technology is the solid-state Li^+-conducting ceramic material. Developing solid-state lithium-air batteries (SSLAB) can solve the problem of applicability fundamentally and circumvent the safety issues completely, and it is also an important avenue to improve the stability of the battery system. In this paper, we provide a systematical review of the progress in the cell construction, the regulation of the electrode/electrolyte interface, the cell assembly, the electrochemical performance and the mechanism for the SSLAB. In every section, the contributions of the recent research progress in the main challenges and the remained questions will be commented. Based on these reviews, we attempt to propose some alternative approaches for the next stage and suggest a development prospective for the SSLAB. 展开更多
关键词 Solid-state lithium-air batteries Solid-state Li^+-conducting ceramic material Interfacial regulation technology In situ formation of passivation film Frameworks structure
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观察电针健康受试者不同经穴对Resting-state fMRI脑功能连接的影响 被引量:10
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作者 石文英 李平 +7 位作者 娄必丹 李金香 范磊 罗容 唐健 周有君 廖玲 章薇 《中华中医药学刊》 CAS 北大核心 2017年第12期3029-3032,I0017,共5页
目的:观察比较电针心经穴与心包经穴时激活脑区的功能连接变化差异,为临床运用针刺心经、心包经穴治疗相关疾病提供实验依据。方法:将符合纳入标准的29例健康受试者随机分为电针心经穴组14例和电针心包经穴组15例,以双侧后扣带回为种子... 目的:观察比较电针心经穴与心包经穴时激活脑区的功能连接变化差异,为临床运用针刺心经、心包经穴治疗相关疾病提供实验依据。方法:将符合纳入标准的29例健康受试者随机分为电针心经穴组14例和电针心包经穴组15例,以双侧后扣带回为种子点,采用功能连接作为观察指标,分析两组电针刺激状态下脑功能连接的差异。结果:两组电针前静息状态下的脑功能连接比较未发现存在明显差异的脑区。电针心经穴与心包经穴时脑内功能网络均发生改变,前者出现功能连接增强的区域为右侧额下回、左侧颞下回、右侧顶下小叶、右侧海马旁回,新激活脑区为双侧中央后回、左侧中央前回、右侧楔前叶、左侧角回、左侧枕下回、左侧脑岛(P<0.05);后者出现功能连接增强的区域为右侧顶上小叶,新激活脑区为左侧小脑舌、左侧顶叶楔前叶、右侧枕下回、左侧豆状核、右侧脑岛(P<0.05)。结论:(1)大脑在无任务的安静、清醒状态下存在一定的功能活动。(2)电针心经、心包经穴广泛激活的脑区主要与精神、神志、智力等密切相关,为临床上选用二者治疗与上述脑区相关的精神、神志类疾病提供了重要的客观依据。电针心经激活的中央前回为皮质运动前区,与对侧肢体运动功能密切相关,它的激活为临床上治疗中风肢体功能障碍选用手少阴心经穴提供了佐证。两组均激活的脑岛与心血管的功能关系密切,为临床上选用心经、心包经穴治疗心血管病提供了部分影像学依据。两条经脉的主治有交叉性,均可用于治疗心脑相关疾病,同时又各有偏颇,心包经多用于治疗与心相关疾病,而心经更多用于治疗精神神志类疾病。 展开更多
关键词 电针 心经 心包经 Resting—state fMRI 功能连接
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Analysis of Reliability for 3-State Device Network with Link-Capacities 被引量:2
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作者 Zhang Ying Liu Yanqiu(Department of Mathematics and Physics, Shenyang Polytechnic University,110023, P. R. China)Wang Dingwei(Department of Systems Engineering, Northeastern University,Shenyang 110023, P. R.China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1999年第2期69-74,共6页
This paper presents a concept of the 3-state device system with link-capacity, whichcan, besides its normal operative state, assume two different failure states: an open-mode and ashorted-mode failure state. The 3-sta... This paper presents a concept of the 3-state device system with link-capacity, whichcan, besides its normal operative state, assume two different failure states: an open-mode and ashorted-mode failure state. The 3-state system reliability analysis often uses flow required andprobability of the device to compute the probability of the system with link-capacity. We use themethod of max-flow and min-cut theorem, give four theorems to reduce 3-state device network withlink-capacity reliability problems to 2-state problems. For practical, relevant network sizes (up to100 components), the algorithm is fast and efficient. 展开更多
关键词 Reliability analysis 3-state system Structure function Capacity.
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Resting-state fMRI studies in epilepsy 被引量:11
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作者 Wurina Yu-Feng Zang Shi-Gang Zhao 《Neuroscience Bulletin》 SCIE CAS CSCD 2012年第4期449-455,共7页
Epilepsy is a disease characterized by abnormal spontaneous activity in the brain.Resting-state functional magnetic resonance imaging(RS-fMRI) is a powerful technique for exploring this activity.With good spatial an... Epilepsy is a disease characterized by abnormal spontaneous activity in the brain.Resting-state functional magnetic resonance imaging(RS-fMRI) is a powerful technique for exploring this activity.With good spatial and temporal resolution,RS-fMRI is a promising approach for accurate localization of the focus of seizure activity.Although simultaneous electroencephalogram-fMRI has been performed with patients in the resting state,most studies focused on activation.This mini-review focuses on RS-fMRI alone,including its computational methods and its application to epilepsy. 展开更多
关键词 resting-state fMRI EPILEPSY LOCALIZATION NETWORK
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LiNbO3-coated LiNi0.8Co0.1Mn0.1O2 cathode with high discharge capacity and rate performance for all-solid-state lithium battery 被引量:18
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作者 Xuelei Li Liubing Jin +5 位作者 Dawei Song Hongzhou Zhang Xixi Shi Zhenyu Wang Lianqi Zhang Lingyun Zhu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第1期39-45,I0002,共8页
In order to obtain high power density,energy density and safe energy storage lithium ion batteries(LIB)to meet growing demand for electronic products,oxide cathodes have been widely explored in all-solidstate lithium ... In order to obtain high power density,energy density and safe energy storage lithium ion batteries(LIB)to meet growing demand for electronic products,oxide cathodes have been widely explored in all-solidstate lithium batteries(ASSLB)using sulfide solid electrolyte.However,the electrochemical performances are still not satisfactory,due to the high interfacial resistance caused by severe interfacial instability between sulfide solid electrolyte and oxide cathode,especially Ni-rich oxide cathodes,in charge-discharge process.Ni-rich LiNi0.8Co0.1Mn0.1O2(NCM811)material at present is one of the most key cathode candidates to achieve the high energy density up to 300 Wh kg^-1 in liquid LIB,but rarely investigated in ASSLB using sulfide electrolyte.To design the stable interface between NCM811 and sulfide electrolyte should be extremely necessary.In this work,in view of our previous work,LiNbO3 coating with about 1 wt% content is adopted to improve the interfacial stability and the electrochemical performances of NCM811 cathode in ASSLB using Li10GeP2S12 solid electrolyte.Consequently,LiNbO3-coated NCM811 cathode displays the higher discharge capacity and rate performance than the reported oxide electrodes in ASSLB using sulfide solid electrolyte to our knowledge. 展开更多
关键词 All-solid-state lithium battery Sulfide electrolyte LiNi_(0.8)Co_(0.1)Mn_(0.1)O_2 LiNbO_3 Electrochemical performances
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Composite solid electrolyte of Na3PS4-PEO for all-solid-state SnS2/Na batteries with excellent interfacial compatibility between electrolyte and Na metal 被引量:9
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作者 Xiaoyan Xu Yuanyuan Li +6 位作者 Jun Cheng Guangmei Hou Xiangkun Nie Qing Ai Linna Dai Jinkui Feng Lijie Ci 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第2期73-78,共6页
High ionic conductivity and superior interfacial stability of solid electrolytes at the electrodes are crucial factors for high-performance all-solid-state sodium batteries. Herein, a composite solid electrolyte Na3PS... High ionic conductivity and superior interfacial stability of solid electrolytes at the electrodes are crucial factors for high-performance all-solid-state sodium batteries. Herein, a composite solid electrolyte Na3PS4-polyethylene oxide is synthesized by the solution-phase reaction method with an improved ionic conductivity up to 9.4 × 10-5 S/cm at room temperature. Moreover, polyethylene oxide polymer layer is wrapped homogeneously on the surface of Na3PS4 particles, which could effectively avoid the direct contact between Na3PS4 electrolyte and sodium metal, thus alleviate their side reactions. We demonstrate that all-solid-state battery SnS2/Na with the composite solid electrolyte Na3PS4-polyethylene oxide delivers an enhanced electrochemical performance with 230 m Ah/g after 40 cycles. 展开更多
关键词 COMPOSITE solid ELECTROLYTE NA 3PS4 ALL-SOLID-state sodium battery SnS2
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Complete Bell-state analysis for a single-photon hybrid entangled state 被引量:3
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作者 盛宇波 周澜 +3 位作者 程维文 巩龙龑 王磊 赵生妹 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期179-183,共5页
We propose a scheme capable of performing complete Bell-state analysis for a single-photon hybrid entangled state.Our single-photon state is encoded in both polarization and frequency degrees of freedom.The setup of t... We propose a scheme capable of performing complete Bell-state analysis for a single-photon hybrid entangled state.Our single-photon state is encoded in both polarization and frequency degrees of freedom.The setup of the scheme is composed of polarizing beam splitters,half wave plates,frequency shifters,and independent wavelength division multiplexers,which are feasible using current technology.We also show that with this setup we can perform complete two-photon Bell-state analysis schemes for polarization degrees of freedom.Moreover,it can also be used to perform the teleportation scheme between different degrees of freedom.This setup may allow extensive applications in current quantum communications. 展开更多
关键词 quantum communication hybrid entangled state Bell-state analysis
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Regional homogeneity abnormalities in patients with tensiontype headache:a resting-state fMRI study 被引量:8
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作者 Pian Wang Handan Du +4 位作者 Ning Chen Jian Guo Qiyong Gong Junran Zhang Li He 《Neuroscience Bulletin》 SCIE CAS CSCD 2014年第6期949-955,共7页
Tension-type headache(TTH) is the most prevalent type of primary headache. Many studies have shown that the pathogenesis of primary headache is associated with fine structural or functional changes. However, these s... Tension-type headache(TTH) is the most prevalent type of primary headache. Many studies have shown that the pathogenesis of primary headache is associated with fine structural or functional changes. However, these studies were mainly based on migraine. The present study aimed to investigate whether TTH patients show functional disturbances compared with healthy subjects. We used restingstate functional magnetic resonance imaging(f MRI) and regional homogeneity(Re Ho) analysis to identify changes in the local synchronization of spontaneous activity in patients with TTH. Ten patients with TTH and 10 age-, gender-, and education-matched healthy controls participated in the study. After demographic and clinical characteristics were acquired, a 3.0-T MRI system was used to obtain restingstate f MRIs. Compared with healthy controls, the TTH group exhibited significantly lower Re Ho values in the bilateral caudate nucleus, the precuneus, the putamen, the left middle frontal gyrus, and the superior frontal gyrus. There was no correlation between mean Re Ho values in TTH patients and duration of TTH, number of attacks, duration of daily attacks, Visual Analogue Scale score, or Headache Impact Test-6 score. These results suggest that TTHpatients exhibit reduced synchronization of neuronal activity in multiple regions involved in the integration and processing of pain signals. 展开更多
关键词 tension-type headache resting-state fMRI ReHo basal ganglia
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Observing the steady-state visual evoked potentials with a compact quad-channel spin exchange relaxation-free magnetometer 被引量:5
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作者 Peng-Cheng Du Jian-Jun Li +4 位作者 Si-Jia Yang Xu-Tong Wang Yan Zhuo Fan Wang Ru-Quan Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第4期141-144,共4页
We observed the steady-state visually evoked potential(SSVEP) from a healthy subject using a compact quad-channel potassium spin exchange relaxation-free(SERF) optically pumped magnetometer(OPM). To this end, 30 s of ... We observed the steady-state visually evoked potential(SSVEP) from a healthy subject using a compact quad-channel potassium spin exchange relaxation-free(SERF) optically pumped magnetometer(OPM). To this end, 30 s of data were collected, and SSVEP-related magnetic responses with signal intensity ranging from 150 fT to 300 f T were observed for all four channels. The corresponding signal to noise ratio(SNR) was in the range of 3.5–5.5. We then used different channels to operate the sensor as a gradiometer. In the specific case of detecting SSVEP, we noticed that the short channel separation distance led to a strongly diminished gradiometer signal. Although not optimal for the case of SSVEP detection, this set-up can prove to be highly useful for other magnetoencephalography(MEG) paradigms that require good noise cancellation.Considering its compactness, low cost, and good performance, the K-SERF sensor has great potential for biomagnetic field measurements and brain-computer interfaces(BCI). 展开更多
关键词 optically pumped MAGNETOMETERS steady-state visually EVOKED potentials MAGNETOENCEPHALOGRAPHY
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Optimization of Solid-State Fermentation with Lactobacillus brevis and Aspergillus oryzae for Trypsin Inhibitor Degradation in Soybean Meal 被引量:19
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作者 GAO You-ling WANG Cai-sheng +1 位作者 ZHU Qiu-hua QIAN Guo-ying 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第5期869-876,共8页
The aim of the present study was to optimize trypsin inhibitor degradation in soybean meal by solid-state fermentation (SSF) with Lactobacillus brevis and Aspergillus oryzae, and to determine the effect of SSF on ph... The aim of the present study was to optimize trypsin inhibitor degradation in soybean meal by solid-state fermentation (SSF) with Lactobacillus brevis and Aspergillus oryzae, and to determine the effect of SSF on phytic acid, crude protein, crude fat, and amino acid profile. Response surface methodology (RSM) with Box-Behnken design was used to optimize SSF. The optimal conditions derived from RSM for L. brevis fermentation were: pH=5. 1; inoculum size=10%; duration=72 h; substrate to water ratio=1.5. The minimum content of trypsin inhibitors was 6.4 mg g^-1 dry matter. The optimal conditions derived from RSM for A. oryzae fermentation were: substrate to water ratio= 0.8 1; inoculum size=4%; duration=120 h. The minimum content of trypsin inhibitors was 1.6 mg g^-1 dry matter. Both L. brevis and A. oryzae decreased trypsin inhibitors dramatically (57.1 and 89.2% respectively). L. brevis fermentation did not affect phytic acid (0.4%) and crude fat (5.2%) considerably, whereas A. oryzae fermentation degraded phytic acid (34.8%) and crude fat (22.0%) contents to a certain extent. Crude protein content was increased after both fermentation (6.4 and 12.9% for L. brevis and A. oryzae respectively). Urease activity was reduced greatly (83.3 and 58.3% for L. brevis and A. oryzae respectively). In conclusion, SSF with A. oryzae and L. brevis reduced trypsin inhibitor content and modified major macronutrients in soybean meal. 展开更多
关键词 Aspergillus oryzae Lactobacillus brevis response surface methodology solid-state fermentation soybean meal trypsin inhibitors
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The development of brain functional connectivity networks revealed by resting-state functional magnetic resonance imaging 被引量:4
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作者 Chao-Lin Li Yan-Jun Deng +2 位作者 Yu-Hui He Hong-Chang Zhai Fu-Cang Jia 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第8期1419-1429,共11页
Previous studies on brain functional connectivity networks in children have mainly focused on changes in function in specific brain regions, as opposed to whole brain connectivity in healthy children. By analyzing the... Previous studies on brain functional connectivity networks in children have mainly focused on changes in function in specific brain regions, as opposed to whole brain connectivity in healthy children. By analyzing the independent components of activation and network connectivity between brain regions, we examined brain activity status and development trends in children aged 3 and 5 years. These data could provide a reference for brain function rehabilitation in children with illness or abnormal function. We acquired functional magnetic resonance images from 15 3-year-old children and 15 5-year-old children under natural sleep cond让ions. The participants were recruited from five kindergartens in the Nanshan District of Shenzhen City, China. The parents of the participants signed an informed consent form with the premise that they had been fully informed regarding the experimental protocol. We used masked independent component analysis and BrainNet Viewer software to explore the independent components of the brain and correlation connections between brain regions. We identified seven independent components in the two groups of children, including the executive control network, the dorsal attention network, the default mode network, the left frontoparietal network, the right frontoparietal network, the salience network, and the motor network. In the default mode network, the posterior cingulate cortex, medial frontal gyrus, and inferior parietal lobule were activated in both 3- and 5-year-old children, supporting the "three-brain region theory” of the default mode network. In the frontoparietal network, the frontal and parietal gyri were activated in the two groups of children, and functional connectivity was strengthened in 5-year-olds compared with 3-year-olds, although the nodes and network connections were not yet mature. The high-correlation network connections in the default mode networks and dorsal attention networks had been significantly strengthened in 5-year-olds vs. 3-year-olds. Further, the salience network in the 3-year-old children included an activated insula/inferior frontal gyrus-anterior cingulate cortex network circu让 and an activated thalamus-parahippocampal-posterior cingulate cortex-subcortical regions network circuit. By the age of 5 years, no des and high-correlation network connections (edges) were reduced in the salience network. Overall, activation of the dorsal attention network, default mode network, left frontoparietal network, and right frontoparietal network increased (the volume of activation increased, the signals strengthened, and the high-correlation connections increased and strengthened) in 5-year-olds compared with 3-year-olds, but activation in some brain nodes weakened or disappeared in the salience network, and the network connections (edges) were reduced. Between the ages of 3 and 5 years, we observed a tendency for function in some brain regions to be strengthened and for the generalization of activation to be reduced, indicating that specialization begins to develop at this time. The study protocol was approved by the local ethics committee of the Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences in China with approval No. SIAT-IRB- 131115-H0075 on November 15, 2013. 展开更多
关键词 nerve REGENERATION FUNCTIONAL MRI BRAIN network FUNCTIONAL connectivity RESTING-state ICA BRAIN development children RESTING-state NETWORKS INFANT template standardized neural REGENERATION
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Altered Resting-State Signals in Patients with Acute Stroke In or Under the Thalamus 被引量:6
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作者 Lijun Chen Chuanfu Li +9 位作者 Jian Zhai Anqin Wang Qin Song Ying Liu Ru Ma Long Han Yamikani Ndasaukas Xiaoming Li Hai Li Xiaochu Zhang 《Neuroscience Bulletin》 SCIE CAS CSCD 2016年第6期585-590,共6页
Abstract Previous studies have suggested that cortical functional reorganization is associated with motor recovery after stroke and that normal afferent sensory information is very important in that process. In this s... Abstract Previous studies have suggested that cortical functional reorganization is associated with motor recovery after stroke and that normal afferent sensory information is very important in that process. In this study, we selected patients who had a stroke in or under the thalamus, with potentially impaired afferent sensory information and analyzed the differences between these patients and healthy controls at three levels: brain regions, the functional con- nectivity between brain areas, and the whole-brain func- tional network. Compared with healthy controls, regionalhomogeneities in the left middle temporal gyrus decreased and functional connectivity between the left middle tem- poral gyrus and the stroke area increased in the patients. However, there was no significant change in the whole- brain functional network. By focusing on stroke located in or under the thalamus, our study contributes to wider inquiries into understanding and treating stroke. 展开更多
关键词 ReHo - Stroke Thalamus - Resting-state
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All-solid-state lithium batteries with inorganic solid electrolytes:Review of fundamental science 被引量:11
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作者 姚霞银 黄冰心 +5 位作者 尹景云 彭刚 黄祯 高超 刘登 许晓雄 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第1期212-225,共14页
The scientific basis of all-solid-state lithium batteries with inorganic solid electrolytes is reviewed briefly, touching upon solid electrolytes, electrode materials, electrolyte/electrode interface phenomena, fabric... The scientific basis of all-solid-state lithium batteries with inorganic solid electrolytes is reviewed briefly, touching upon solid electrolytes, electrode materials, electrolyte/electrode interface phenomena, fabrication, and evaluation. The challenges and prospects are outlined as well. 展开更多
关键词 all-solid-state lithium batteries inorganic solid electrolytes interface phenomena rechargeablelithium batteries
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NASICON-structured Na3.1Zr1.95Mg0.05Si2PO12 solid electrolyte for solid-state sodium batteries 被引量:14
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作者 Jing Yang HongLi Wan +4 位作者 ZhiHua Zhang GaoZhan Liu XiaoXiong Xu YongSheng Hu Xia-Yin Yao 《Rare Metals》 SCIE EI CAS CSCD 2018年第6期480-487,共8页
Using stable inorganic solid electrolyte to replace organic liquid electrolyte could significantly reduce potential safety risks of rechargeable batteries. Na-superionic conductor (NASICON)-structured solid electrol... Using stable inorganic solid electrolyte to replace organic liquid electrolyte could significantly reduce potential safety risks of rechargeable batteries. Na-superionic conductor (NASICON)-structured solid electrolyte is one of the most promising sodium solid electrolytes and can be employed in solid-state sodium batteries. In this work, a NASICON-structured solid electrolyte Na3.1Zr1.95Mg0.05Si2PO12 was synthesized through a facile solid-state reaction, yielding high sodium-ionic conductivity of 1.33 × 10-3 S.cm^-1 at room temperature. The results indicate that Mg^2+ is a suitable and economical substitution ion to replace Zr^4+, and this synthesis route can be scaled up for powder preparation with low cost. In addition to electrolyte material preparation, solid-state batteries with Na3.1Zr1.95Mg0.05Si2PO12 as electrolyte were assembled. A specific capacity of 57.9 mAh·g^-1 is maintained after 100 cycles under a current density of 0.5C rate at room temperature. The favorable cycling performance of the solid-state battery suggests that Na3.1Zr1.95Mg0.05Si2PO12 is an ideal electrolyte candidate for solid-state sodium batteries. 展开更多
关键词 Solid electrolyte NASICON-type structure Sodium-ionic conductivity Solid-state sodium battery
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Impact of Typical Steady-state Conditions and Transient Conditions on Flow Ripple and Its Test Accuracy for Axial Piston Pump 被引量:15
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作者 XU Bing HU Min ZHANG Junhui 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第5期1012-1022,共11页
The current research about the flow ripple of axial piston pump mainly focuses on the effect of the structure of parts on the flow ripple. Therein, the structure of parts are usually designed and optimized at rated wo... The current research about the flow ripple of axial piston pump mainly focuses on the effect of the structure of parts on the flow ripple. Therein, the structure of parts are usually designed and optimized at rated working conditions. However, the pump usually has to work in large-scale and time-variant working conditions. Therefore, the flow ripple characteristics of pump and analysis for its test accuracy with respect to variant steady-state conditions and transient conditions in a wide range of operating parameters are focused in this paper. First, a simulation model has been constructed, which takes the kinematics of oil film within friction pairs into account for higher accuracy. Afterwards, a test bed which adopts Secondary Source Method is built to verify the model. The simulation and tests results show that the angular position of the piston, corresponding to the position where the peak flow ripple is produced, varies with the different pressure. The pulsating amplitude and pulsation rate of flow ripple increase with the rise of pressure and the variation rate of pressure. For the pump working at a constant speed, the flow pulsation rate decreases dramatically with the increasing speed when the speed is less than 27.78% of the maximum speed, subsequently presents a small decrease tendency with the speed further increasing. With the rise of the variation rate of speed, the pulsating amplitude and pulsation rate of flow ripple increase. As the swash plate angle augments, the pulsating amplitude of flow ripple increases, nevertheless the flow pulsation rate decreases. In contrast with the effect of the variation of pressure, the test accuracy of flow ripple is more sensitive to the variation of speed. It makes the test accuracy above 96.20% available for the pulsating amplitude of pressure deviating within a range of ~6% from the mean pressure. However, with a variation of speed deviating within a range of ±2% from the mean speed, the attainable test accuracy of flow ripple is above 93.07%. The model constructed in this research proposes a method to determine the flow ripple characteristics of pump and its attainable test accuracy under the large-scale and time-variant working conditions. Meanwhile, a discussion about the variation of flow ripple and its obtainable test accuracy with the conditions of the pump working in wide operating ranges is given as well. 展开更多
关键词 axial piston pump flow ripple test accuracy steady-state condition transient condition wide operating ranges
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Altered regional homogeneity in post-traumatic stress disorder: a resting-state functional magnetic resonance imaging study 被引量:11
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作者 Yan Yin Changfeng Jin +9 位作者 Lisa T. Eyler Hua Jin Xiaolei Hu Lian Duan Huirong Zheng Bo Feng Xuanyin Huang Baoci Shan Qiyong Gong Lingjiang Li 《Neuroscience Bulletin》 SCIE CAS CSCD 2012年第5期541-549,共9页
Objective Little is known about the brain systems that contribute to vulnerability to post-traumatic stress disorder (PTSD). Comparison of the resting-state patterns of intrinsic functional synchronization, as measu... Objective Little is known about the brain systems that contribute to vulnerability to post-traumatic stress disorder (PTSD). Comparison of the resting-state patterns of intrinsic functional synchronization, as measured by functional magnetic resonance imaging (fMRI), between groups with and without PTSD following a traumatic event can help identify the neural mechanisms of the disorder and targets for intervention. Methods Fifty-four PTSD patients and 72 matched traumatized subjects who experienced the 2008 Sichuan earthquake were imaged with blood oxygen level-dependent (BOLD) fMRI and analyzed using the measure of regional homogeneity (ReHo) during the resting state. Results PTSD patients presented enhanced ReHo in the left inferior parietal lobule and right superior frontal gyrus, and reduced ReHo in the right middle temporal gyrus and lingual gyrus, relative to traumatized individuals without PTSD. Conclusion Our findings showed that abnormal brain activity exists under resting conditions in PTSD patients who had been exposed to a major earthquake. Alterations in the local functional connectivity of cortical regions are likely to contribute to the neural mechanisms underlying PTSD. 展开更多
关键词 functional magnetic resonance imaging post-traumatic stress disorder regional homogeneity RESTING-state
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Aberrant Resting-State Functional Connectivity in the Default Mode Network in Pediatric Bipolar Disorder Patients with and without Psychotic Symptoms 被引量:6
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作者 Yuan Zhong Chun Wang +5 位作者 Weijia Gao Qian Xiao Dali Lu Qing Jiao Linyan Su Guangming Lu 《Neuroscience Bulletin》 SCIE CAS CSCD 2019年第4期581-590,共10页
Mood disorders/psychosis have been associated with dysfunctions in the default mode network(DMN).However,the relative contributions of DMN regions to state and trait disturbances in pediatric bipolar disorder(PBD)rema... Mood disorders/psychosis have been associated with dysfunctions in the default mode network(DMN).However,the relative contributions of DMN regions to state and trait disturbances in pediatric bipolar disorder(PBD)remain unclear.The aim of this study was to investigate the possible mechanisms of PBD through brain imaging and explore the influence of psychotic symptoms on functional alterations in PBD patients.Twenty-nine psychotic and 26 non-psychotic PBD patients,as well as 19 age-and sex-matched healthy controls underwent a restingstate functional MRI scan and the data were analyzed by independent component analysis.The DMN component from the fMRI data was extracted for each participant.Spearman's rank correlation analysis was performed between aberrant connectivity and clinical measurements.The results demonstrated that psychotic PBD was characterized by aberrant DMN connectivity in the anterior cingulate cortex/medial prefrontal cortex,bilateral caudate nucleus,bilateral angular gyri,and left middle temporal gyrus,while non-psychotic PBD was not,suggesting further impairment with the development of psychosis.In summary,we demonstrated unique impairment in DMN functional connectivity in the psychotic PBD group.These specific neuroanatomical abnormalities may shed light on the underlying pathophysiology and presentation of PBD. 展开更多
关键词 Pediatric bipolar DISORDER DEFAULT mode RESTING-state fMRI Functional connectivity PSYCHOTIC SYMPTOM
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Effects of high-pressure heat treatment on the solid-state phase transformation and microstructures of Cu_(61.13)Zn_(33.94)Al_(4.93) alloys 被引量:8
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作者 王海燕 刘建华 +1 位作者 彭桂荣 王文魁 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期469-474,共6页
The phase transformation activation energy of the Cu61.13Zn33.94A14.93 alloys, which were treated at 4 GPa and 700 ℃ for 15 minutes, was calculated by means of differential scanning calorimetry curves obtained at var... The phase transformation activation energy of the Cu61.13Zn33.94A14.93 alloys, which were treated at 4 GPa and 700 ℃ for 15 minutes, was calculated by means of differential scanning calorimetry curves obtained at various heating and cooling rates. Then, the effects of high-pressure heat treatments on the solid-state phase transformation and the microstructures of Cu61.13Zn33.94A14.93 alloys were investigated. The results show that high-pressure heat treatments can refine the grains and can change the preferred orientation from (111) to (200) of α phase. Compared with the as-cast alloy, the sample with high-pressure heat treatment has finer grains, lower β'→β and/β→β' transformation temperature and activation energy. Furthermore, we found that high cooling rate favours the formation of fine needle-like α phase in the range of 5-20℃/min. 展开更多
关键词 Cu61.13Zn33.94A14.93 alloy high-pressure heat treatment solid-state phase transformation MICROSTRUCTURES
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Steady-state responses of a belt-drive dynamical system under dual excitations 被引量:6
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作者 Hu Ding 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第1期156-169,共14页
The stable steady-state periodic responses of a belt-drive system with a one-way clutch are studied. For the first time, the dynamical system is investigated under dual excitations. The system is simultaneously excite... The stable steady-state periodic responses of a belt-drive system with a one-way clutch are studied. For the first time, the dynamical system is investigated under dual excitations. The system is simultaneously excited by the firing pulsations of the engine and the harmonic motion of the foundation. Nonlinear discrete-continuous equations are derived for coupling the transverse vibration of the belt spans and the rotations of the driving and driven pulleys and the accessory pulley. The nonlinear dynamics is studied under equal and multiple relations between the frequency of the fir- ing pulsations and the frequency of the foundation motion. Furthermore, translating belt spans are modeled as axially moving strings. A set of nonlinear piecewise ordinary differ- ential equations is achieved by using the Galerkin truncation. Under various relations between the excitation frequencies, the time histories of the dynamical system are numerically simulated based on the time discretization method. Further- more, the stable steady-state periodic response curves are calculated based on the frequency sweep. Moreover, the convergence of the Galerkin truncation is examined. Numer- ical results demonstrate that the one-way clutch reduces the resonance amplitude of the rotations of the driven pul- ley and the accessory pulley. On the other hand, numerical examples prove that the resonance areas of the belt spans are decreased by eliminating the torque-transmitting in the opposite direction. With the increasing amplitude of the foun- dation excitation, the damping effect of the one-way clutch will be reduced. Furthermore, as the amplitude of the firing pulsations of the engine increases, the jumping phenomena in steady-state response curves of the belt-drive system with or without a one-way clutch both occur. 展开更多
关键词 Nonlinear vibration One-way clutch Dynamical system Steady-state responses Galerkinmethod
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New thermal optimization scheme of power module in solid-state amplifier 被引量:4
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作者 Lie-Peng Sun Zhen-Yu Yuan +5 位作者 Cheng Zhang Xian-Bo Xu Jun-Gang Miao Jian-Hua Zhang Long-Bo Shi Yuan He 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第4期143-149,共7页
The new 1 kW power module for ADS project needs the optimization of cooling design including water flow and tunnel layout, and the water flow of three tons per hour was chosen to be a goal for a 20 kW power source.Acc... The new 1 kW power module for ADS project needs the optimization of cooling design including water flow and tunnel layout, and the water flow of three tons per hour was chosen to be a goal for a 20 kW power source.According to analysis from the insertion and integrated loss, about 24 modules were integrated into the rated power. Thus, every module has a cooling flow of 2.1 L/min for RF heat load and power supply loss, which is very hard to achieve if no special consideration and techniques. A new thermal simulation method was introduced for thermal analysis of cooling plate through CST multi-physics suite,especially for temperature of power LDMOS transistor.Some specific measures carried out for the higher heat transfer were also presented in this paper. 展开更多
关键词 RF system SOLID-state AMPLIFIER Power MODULE HEAT TRANSFER COEFFICIENT
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