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Enhancing the stability of Ni Fe-layered double hydroxide nanosheet array for alkaline seawater oxidation by Ce doping
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作者 Yongchao Yao Shengjun Sun +14 位作者 hui zhang Zixiao Li Chaoxin Yang Zhengwei Cai Xun He Kai Dong Yonglan Luo Yan Wang Yuchun Ren Qian Liu Dongdong Zheng Weihua Zhuang Bo Tang Xuping Sun Wenchuang(Walter)Hu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期306-312,共7页
Electrocatalytic hydrogen production from seawater holds enormous promise for clean energy generation.Nevertheless,the direct electrolysis of seawater encounters significant challenges due to poor anodic stability cau... Electrocatalytic hydrogen production from seawater holds enormous promise for clean energy generation.Nevertheless,the direct electrolysis of seawater encounters significant challenges due to poor anodic stability caused by detrimental chlorine chemistry.Herein,we present our recent discovery that the incorporation of Ce into Ni Fe layered double hydroxide nanosheet array on Ni foam(Ce-Ni Fe LDH/NF)emerges as a robust electrocatalyst for seawater oxidation.During the seawater oxidation process,CeO_(2)is generated,effectively repelling Cl^(-)and inhibiting the formation of Cl O-,resulting in a notable enhancement in the oxidation activity and stability of alkaline seawater.The prepared Ce-Ni Fe LDH/NF requires only overpotential of 390 m V to achieve the current density of 1 A cm^(-2),while maintaining long-term stability for 500 h,outperforming the performance of Ni Fe LDH/NF(430 m V,150 h)by a significant margin.This study highlights the effectiveness of a Ce-doping strategy in augmenting the activity and stability of materials based on Ni Fe LDH in seawater electrolysis for oxygen evolution. 展开更多
关键词 Ce doping NiFe layered double hydroxide Seawater oxidation ELECTROCATALYSIS Cl^(-) repulsion
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Lactobacillus plantarum AR113 attenuates liver injury in D-galactose-induced aging mice via the inhibition of oxidative stress and endoplasmic reticulum stress
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作者 Yongjun Xia Yujie Gong +8 位作者 Xiangna Lin Yijin Yang Xin Song Guangqiang Wang Zhiqiang Xiong Yangyang Qian Zhuan Liao hui zhang Lianzhong Ai 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期885-897,共13页
Probiotics could effectively eliminate excess reactive oxygen species(ROS)generated during aging or lipid metabolism disorders,but their mechanism is unclear.The major purpose of this study was to investigate the mech... Probiotics could effectively eliminate excess reactive oxygen species(ROS)generated during aging or lipid metabolism disorders,but their mechanism is unclear.The major purpose of this study was to investigate the mechanism of Lactiplantibacillus plantarun AR113 alleviating oxidative stress injury in the D-galactose induced aging mice.The result showed that pretreatment with L.plantarun AR113 significantly relieving H_(2)O_(2)induced cytotoxicity in HepG2 cells by maintain cell membrane integrity and increasing antioxidant enzyme activities.In D-galactose induced aging mice,L.plantarun AR113 could significantly attenuate liver damage and inflammatory infiltration by promoting endogenous glutathione(GSH)synthesis and activating the Nrf2/Keap1 signaling pathway in mice,and increasing the expression of regulated phaseⅡdetoxification enzymes and antioxidant enzymes.Further analysis shown that gavage of L.plantarun AR113 could significantly reduce the expression of G protein-coupled receptor 78(GPR78)and C/EBP homologous protein(CHOP)proteins,and promote the restoration of endoplasmic reticulum(ER)homeostasis,thereby activating cell anti-apoptotic pathways.These results were also confirmed in H_(2)O_(2)-treated HepG2 experiments.It indicated that L.plantarun AR113 could inhibit D-galactose-induced liver injury through dual inhibition of ER stress and oxidative stress.L.plantarun AR113 have good application potential in anti-aging and alleviating metabolic disorders. 展开更多
关键词 Lactiplantibacillus plantarun AR113 HEPG2 D-GALACTOSE Oxidative stress ER stress
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Design of the electron cyclotron emission diagnostic on EXL-50 spherical torus
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作者 王嵎民 谢奇峰 +10 位作者 陶仁义 张辉 薄晓坤 孙恬恬 伦秀春 陈琳 谭伟强 郭栋 邓必河 刘敏胜 the EXL-50 Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期53-60,共8页
The electron cyclotron emission(ECE)diagnostic system has been developed on the ENN spherical torus(EXL-50).The ECE system is designed to detect radiation emitted by energetic electrons,rather than conventional 1D ele... The electron cyclotron emission(ECE)diagnostic system has been developed on the ENN spherical torus(EXL-50).The ECE system is designed to detect radiation emitted by energetic electrons,rather than conventional 1D electron temperature profile measurement,in the frequency range of 4-40 GHz.The system is composed of five subsystems,each covering a different frequency band,including the C-band(4-8 GHz),X-band(8-12 GHz),Ku-band(12-18 GHz),K-band(18-26.5 GHz)and Kα-band(26.4-40 GHz).The system uses heterodyne detection to analyze the received signals.The K-band and Kα-band subsystems are located horizontally in the equatorial plane of the EXL-50,while the C-band,X-band and Ku-band subsystems are located under the vacuum vessel of the EXL-50.To direct the microwaves from the plasma to the antennas for the horizontal detection subsystems,a quasi-optical system has been developed.For the vertical detection subsystems,the antennas are directly attached to the port located beneath the torus at R=700 mm,which is also the magnetic axis of the torus.The system integration,bench testing and initial experimental results will be thoroughly discussed,providing a comprehensive understanding of the ECE system s performance and capabilities. 展开更多
关键词 electron cyclotron emission spherical torus(ST) EXL-50 energetic electrons
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Wireless Positioning:Technologies,Applications,Challenges,and Future Development Trends
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作者 Xingwang Li Hua Pang +4 位作者 Geng Li Junjie Jiang hui zhang Changfei Gu Dong Yuan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1135-1166,共32页
The development of the fifth-generation(5G)mobile communication systems has entered the commercialization stage.5G has a high data rate,low latency,and high reliability that can meet the basic demands of most industri... The development of the fifth-generation(5G)mobile communication systems has entered the commercialization stage.5G has a high data rate,low latency,and high reliability that can meet the basic demands of most industries and daily life,such as the Internet of Things(IoT),intelligent transportation systems,positioning,and navigation.The continuous progress and development of society have aroused wide concern.Positioning accuracy is the core demand for the applications,especially in complex environments such as airports,warehouses,supermarkets,and basements.However,many factors also affect the accuracy of positioning in those environments,for example,multipath effects,non-line-of-sight,and clock synchronization errors.This paper provides a comprehensive review of the existing works about positioning for the future wireless network and discusses its key techniques and algorithms,as well as the current development and future directions.We first outline the current traditional positioning technologies and algorithms,which are discussed and analyzed with the relevant literature.In addition,we also discuss application scenarios for wireless localization.By comparing different positioning systems,the challenges and future development directions of existing wireless positioning systems are prospected. 展开更多
关键词 5G wireless positioning reconfigurable intelligent surface Internet of Vehicles
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Spatial Distribution Feature Extraction Network for Open Set Recognition of Electromagnetic Signal
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作者 hui zhang Huaji Zhou +1 位作者 Li Wang Feng Zhou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期279-296,共18页
This paper proposes a novel open set recognition method,the Spatial Distribution Feature Extraction Network(SDFEN),to address the problem of electromagnetic signal recognition in an open environment.The spatial distri... This paper proposes a novel open set recognition method,the Spatial Distribution Feature Extraction Network(SDFEN),to address the problem of electromagnetic signal recognition in an open environment.The spatial distribution feature extraction layer in SDFEN replaces convolutional output neural networks with the spatial distribution features that focus more on inter-sample information by incorporating class center vectors.The designed hybrid loss function considers both intra-class distance and inter-class distance,thereby enhancing the similarity among samples of the same class and increasing the dissimilarity between samples of different classes during training.Consequently,this method allows unknown classes to occupy a larger space in the feature space.This reduces the possibility of overlap with known class samples and makes the boundaries between known and unknown samples more distinct.Additionally,the feature comparator threshold can be used to reject unknown samples.For signal open set recognition,seven methods,including the proposed method,are applied to two kinds of electromagnetic signal data:modulation signal and real-world emitter.The experimental results demonstrate that the proposed method outperforms the other six methods overall in a simulated open environment.Specifically,compared to the state-of-the-art Openmax method,the novel method achieves up to 8.87%and 5.25%higher micro-F-measures,respectively. 展开更多
关键词 Electromagnetic signal recognition deep learning feature extraction open set recognition
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Jianpi Gushen Huayu decoction ameliorated diabetic nephropathy through modulating metabolites in kidney,and inhibiting TLR4/NF-κB/NLRP3 and JNK/P38 pathways
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作者 Zi-Ang Ma Li-Xin Wang +8 位作者 hui zhang Han-Zhou Li Li Dong Qing-Hai Wang Yuan-Song Wang Bao-ChaoPan Shu-Fang zhang Huan-Tian Cui Shu-Quan Lv 《World Journal of Diabetes》 SCIE 2024年第3期502-518,共17页
BACKGROUND Jianpi Gushen Huayu Decoction(JPGS)has been used to clinically treat diabetic nephropathy(DN)for many years.However,the protective mechanism of JPGS in treating DN remains unclear.AIM To evaluate the therap... BACKGROUND Jianpi Gushen Huayu Decoction(JPGS)has been used to clinically treat diabetic nephropathy(DN)for many years.However,the protective mechanism of JPGS in treating DN remains unclear.AIM To evaluate the therapeutic effects and the possible mechanism of JPGS on DN.METHODS We first evaluated the therapeutic potential of JPGS on a DN mouse model.We then investigated the effect of JPGS on the renal metabolite levels of DN mice using non-targeted metabolomics.Furthermore,we examined the effects of JPGS on c-Jun N-terminal kinase(JNK)/P38-mediated apoptosis and the inflammatory responses mediated by toll-like receptor 4(TLR4)/nuclear factor-kappa B(NF-κB)/NOD-like receptor family pyrin domain containing 3(NLRP3).RESULTS The ameliorative effects of JPGS on DN mice included the alleviation of renal injury and the control of inflammation and oxidative stress.Untargeted metabolomic analysis revealed that JPGS altered the metabolites of the kidneys in DN mice.A total of 51 differential metabolites were screened.Pathway analysis results indicated that nine pathways significantly changed between the control and model groups,while six pathways significantly altered between the model and JPGS groups.Pathways related to cysteine and methionine metabolism;alanine,tryptophan metabolism;aspartate and glutamate metabolism;and riboflavin metabolism were identified as the key pathways through which JPGS affects DN.Further experimental validation showed that JPGS treatment reduced the expression of TLR4/NF-κB/NLRP3 pathways and JNK/P38 pathway-mediated apoptosis related factors.CONCLUSION JPGS could markedly treat mice with streptozotocin(STZ)-induced DN,which is possibly related to the regulation of several metabolic pathways found in kidneys.Furthermore,JPGS could improve kidney inflammatory responses and ameliorate kidney injuries in DN mice via the TLR4/NF-κB/NLRP3 pathway and inhibit JNK/P38 pathwaymediated apoptosis in DN mice. 展开更多
关键词 Diabetic nephropathy Jianpi Gushen Huayu Decoction Oxidative stress Inflammation Untargeted metabolomics Toll-like receptor 4/nuclear factor-kappa B/NOD-like receptor family pyrin domain containing 3 pathway c-Jun N-terminal kinase/P38-mediated apoptosis
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Tailoring electron vortex beams with customizable intensity patterns by electron diffraction holography
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作者 Pengcheng Huo Ruixuan Yu +3 位作者 Mingze Liu hui zhang Yan-qing Lu Ting Xu 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第2期14-21,共8页
An electron vortex beam(EVB) carrying orbital angular momentum(OAM) plays a key role in a series of fundamental scientific researches, such as chiral energy-loss spectroscopy and magnetic dichroism spectroscopy. So fa... An electron vortex beam(EVB) carrying orbital angular momentum(OAM) plays a key role in a series of fundamental scientific researches, such as chiral energy-loss spectroscopy and magnetic dichroism spectroscopy. So far, almost all the experimentally created EVBs manifest isotropic doughnut intensity patterns. Here, based on the correlation between local divergence angle of electron beam and phase gradient along azimuthal direction, we show that free electrons can be tailored to EVBs with customizable intensity patterns independent of the carried OAM. As proof-of-concept, by using computer generated hologram and designing phase masks to shape the incident free electrons in the transmission electron microscope, three structured EVBs carrying identical OAM are tailored to exhibit completely different intensity patterns. Furthermore, through the modal decomposition, we quantitatively investigate their OAM spectral distributions and reveal that structured EVBs present a superposition of a series of different eigenstates induced by the locally varied geometries. These results not only generalize the concept of EVB, but also demonstrate an extra highly controllable degree of freedom for electron beam manipulation in addition to OAM. 展开更多
关键词 electron vortex beam orbital angular momentum diffraction holography
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Analysis of the Reform of Ideological and Political Education in College English Curriculum from the Perspective of“Cultural Confidence”
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作者 hui zhang 《Journal of Contemporary Educational Research》 2024年第2期117-122,共6页
With the rapid development of the education industry,higher requirements have been put forward for college English education and teaching,accelerating the pace of college English reform.Issues such as how to integrate... With the rapid development of the education industry,higher requirements have been put forward for college English education and teaching,accelerating the pace of college English reform.Issues such as how to integrate knowledge transmission,language expression skill improvement,cultural element extraction,and ideological and political education,and present the role of curriculum education function have attracted attention.In the era of informatization,college students’thinking has undergone certain changes and gradually developed towards diversification.Therefore,universities should start from the perspective of cultural confidence,extract valuable ideological and political elements,and explore effective tourism ideological and political teaching methods.While helping college students enhance their cultural confidence,it is also beneficial for them to better inherit traditional Chinese culture.This article conducts an in-depth exploration of ideological and political education in college English courses from the perspective of“cultural confidence”and uses scientific and effective measures to solve the problems encountered,aiming to provide valuable guidelines for relevant researchers. 展开更多
关键词 Cultural confidence College English teaching Course ideological and political education MEASURE
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Research on the Application of Second Language Acquisition Theory in College English Speech Teaching
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作者 hui zhang 《Journal of Contemporary Educational Research》 2024年第3期173-178,共6页
The teaching of English speeches in universities aims to enhance oral communication ability,improve English communication skills,and expand English knowledge,occupying a core position in English teaching in universiti... The teaching of English speeches in universities aims to enhance oral communication ability,improve English communication skills,and expand English knowledge,occupying a core position in English teaching in universities.This article takes the theory of second language acquisition as the background,analyzes the important role and value of this theory in English speech teaching in universities,and explores how to apply the theory of second language acquisition in English speech teaching in universities.It aims to strengthen the cultivation of English skilled talents and provide a brief reference for improving English speech teaching in universities. 展开更多
关键词 Second language acquisition theory Teaching English speeches in universities Practical strategies
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基于加速康复外科理念的去阿片化麻醉镇痛在急诊剖宫产围手术期运用观察 被引量:3
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作者 吴靦 代文化 +6 位作者 曾伟 谢焕龙 李宇琴 蒋红娥 吴演文 张慧 刘前梅 《药物流行病学杂志》 CAS 2023年第2期166-172,共7页
目的探讨基于加速康复外科理念的去阿片化麻醉镇痛在腰硬联合麻醉后急诊剖宫产围手术期的临床运用效果。方法300例急诊剖宫产患者随机分为去阿片化组(OF组)、舒芬太尼组(S组)、吗啡组(M组),每组100例。3组患者术前均采用加速康复外科策... 目的探讨基于加速康复外科理念的去阿片化麻醉镇痛在腰硬联合麻醉后急诊剖宫产围手术期的临床运用效果。方法300例急诊剖宫产患者随机分为去阿片化组(OF组)、舒芬太尼组(S组)、吗啡组(M组),每组100例。3组患者术前均采用加速康复外科策略。OF组术中采用非阿片类药物麻醉镇痛,术毕予氟比洛芬酯+右美托咪定静脉自控镇痛;S组术中予舒芬太尼镇痛,术毕予舒芬太尼+右美托咪定静脉自控镇痛;M组术中予舒芬太尼镇痛,术后予吗啡+罗哌卡因行硬膜外自控镇痛。OF组和S组患者术毕行B超引导下的腰方肌神经阻滞。比较3组患者手术治疗到出院时间、术后首次下床时间、术后24 h产科恢复质量-11评分、术后48 h内动态视觉模拟评分、围手术期并发症等情况。结果与M组相比,OF组和S组手术治疗到出院时间明显缩短,下床活动时间更早,产科恢复质量-11评分更高,皮肤瘙痒发生率更低(P<0.05)。与M组和S组相比,OF组围术期恶心呕吐、腹胀发生率更低(P<0.05)。3组患者的动态视觉模拟评分以及围手术期寒颤、头晕头痛、尿潴留等发生率差异无统计学意义(P>0.05)。结论去阿片化麻醉镇痛在腰硬联合麻醉后急诊剖宫产围手术期中运用效果满意,可缩短剖宫产后住院时间,减少围术期并发症。 展开更多
关键词 加速康复外科 去阿片化麻醉 急诊剖宫产 腰方肌阻滞 多模式镇痛
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Microglial depletion impairs glial scar formation and aggravates inflammation partly by inhibiting STAT3 phosphorylation in astrocytes after spinal cord injury 被引量:5
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作者 Zhi-Lai Zhou Huan Xie +4 位作者 Xiao-Bo Tian Hua-Li Xu Wei Li Shun Yao hui zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第6期1325-1331,共7页
Astrocytes and microglia play an orchestrated role following spinal cord injury;however,the molecular mechanisms through which microglia regulate astrocytes after spinal cord injury are not yet fully understood.Herein... Astrocytes and microglia play an orchestrated role following spinal cord injury;however,the molecular mechanisms through which microglia regulate astrocytes after spinal cord injury are not yet fully understood.Herein,microglia were pharmacologically depleted and the effects on the astrocytic response were examined.We further explored the potential mechanisms involving the signal transducers and activators of transcription 3(STAT3)pathway.For in vivo experiments,we constructed a contusion spinal cord injury model in C57BL/6 mice.To deplete microglia,all mice were treated with colony-stimulating factor 1 receptor inhibitor PLX3397,starting 2 weeks prior to surgery until they were sacrificed.Cell proliferation was examined by 5-ethynyl-2-deoxyuridine(EdU)and three pivotal inflammatory cytokines were detected by a specific Bio-Plex Pro^(TM) Reagent Kit.Locomotor function,neuroinflammation,astrocyte activation and phosphorylated STAT3(pSTAT3,a maker of activation of STAT3 signaling)levels were determined.For in vitro experiments,a microglia and astrocyte coculture system was established,and the small molecule STA21,which blocks STAT3 activation,was applied to investigate whether STAT3 signaling is involved in mediating astrocyte proliferation induced by microglia.PLX3397 administration disrupted glial scar formation,increased inflammatory spillover,induced diffuse tissue damage and impaired functional recovery after spinal cord injury.Microglial depletion markedly reduced EdU+proliferating cells,especially proliferating astrocytes at 7 days after spinal cord injury.RNA sequencing analysis showed that the JAK/STAT3 pathway was downregulated in mice treated with PLX3397.Double immunofluorescence staining confirmed that PLX3397 significantly decreased STAT3 expression in astrocytes.Importantly,in vitro coculture of astrocytes and microglia showed that microglia-induced astrocyte proliferation was abolished by STA21 administration.These findings suggest that microglial depletion impaired astrocyte proliferation and astrocytic scar formation,and induced inflammatory diffusion partly by inhibiting STAT3 phosphorylation in astrocytes following spinal cord injury. 展开更多
关键词 ASTROCYTES COCULTURE colony-stimulating factor 1 receptor inhibitor EdU glia scar inflammatory response microglia PHOSPHORYLATION proliferation spinal cord injury STAT3
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应急治理中的合作生产何以有效?——以中国灾害群测群防体系的实践为例 被引量:3
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作者 张惠 李英祥 邹彤彤 《公共行政评论》 北大核心 2023年第2期44-62,197,共20页
在利益诉求多元的应急治理实践中,公共应急产品的合作生产是应对“政府失灵”与“市场失灵”困境的有效手段,如何提升应急治理中合作生产的有效性已成为增强防灾减灾效能的前沿议题。研究以合作生产理论为基础,从主体能力与主体间关系... 在利益诉求多元的应急治理实践中,公共应急产品的合作生产是应对“政府失灵”与“市场失灵”困境的有效手段,如何提升应急治理中合作生产的有效性已成为增强防灾减灾效能的前沿议题。研究以合作生产理论为基础,从主体能力与主体间关系的整体性视角出发,采用多元回归分析法对四川省汶川县899个家庭户的调研数据展开实证分析,以此识别影响应急治理中合作生产有效性的因素并阐明其内在机理。研究结果表明,主体能力维度中的领导力、学习能力以及主体间关系维度中的信任、凝聚力等要素均对公共应急服务的合作生产有效性产生显著的正向影响。同时,信任作为调节变量,分别强化了凝聚力与领导力对合作生产有效性的正向作用。由此可见,要想实现持续有效的应急公共产品供给,不仅应关注生产主体的能力建设,同时也要重视主体间的互动模式与关系网络,因地制宜地实现应急服务的优化供给。 展开更多
关键词 合作生产 灾害预警 群测群防 社会资本 应急治理
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火星探测和天体矿物手性
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作者 章慧 刘新玲 +5 位作者 南子昂 沙旭明 张仕林 黄少华 苏纪豪 赵玉芬 《大学化学》 CAS 2023年第2期116-131,共16页
从地球到月球到火星,人类一直没有停下探矿寻宝的脚步。从冰洲石到水晶到紫水晶,这些晶莹剔透矿石所呈现的光学现象给科学家带来“光是什么”和“手性起源”的百折不挠探究,贯穿整个科学发展史,促进科学、技术和现代社会进步,并将持续... 从地球到月球到火星,人类一直没有停下探矿寻宝的脚步。从冰洲石到水晶到紫水晶,这些晶莹剔透矿石所呈现的光学现象给科学家带来“光是什么”和“手性起源”的百折不挠探究,贯穿整个科学发展史,促进科学、技术和现代社会进步,并将持续为未来科技发展带来不可估量的影响。 展开更多
关键词 火星探测 天体矿物 手性 冰洲石 水晶 紫水晶 双折射 偏振
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Assessment of strong earthquake risk in the Chinese mainland from 2021 to 2030 被引量:3
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作者 Zhigang Shao Yanqiang Wu +19 位作者 Lingyun Ji Faqi Diao Fuqiang Shi Yujiang Li Feng Long hui zhang Wuxing Wang Wenxin Wei Peng Wang Xiaoxia Liu Qi Liu Zhengyang Pan Xiaofei Yin Yue Liu Wei Feng Zhenyu Zou Jia Cheng Renqi Lu Yueren Xu Xi Li 《Earthquake Research Advances》 CSCD 2023年第1期81-91,共11页
The long-term earthquake prediction from 2021 to 2030 is carried out by researching the active tectonic block boundary zones in the Chinese mainland.Based on the strong earthquake recurrence model,the cumulative proba... The long-term earthquake prediction from 2021 to 2030 is carried out by researching the active tectonic block boundary zones in the Chinese mainland.Based on the strong earthquake recurrence model,the cumulative probability of each target fault in the next 10 years is given by the recurrence period and elapsed time of each fault,which are adopted from relevant studies such as seismological geology,geodesy,and historical earthquake records.Based on the long-term predictions of large earthquakes throughout the world,this paper proposes a comprehensive judgment scheme based on the fault segments with the seismic gap,motion strongly locked,sparse small-moderate earthquakes,and apparent Coulomb stress increase.This paper presents a comprehensive analysis of the relative risk for strong earthquakes that may occur in the coming 10 years on the major faults in the active tectonic block boundary zones in the Chinese mainland.The present loading rate of each fault is first constrained by geodetic observations;the cumulative displacement of each fault is then estimated by the elapsed time since the most recent strong earthquake. 展开更多
关键词 Long-term earthquake prediction Chinese mainland Active tectonic block
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Sediment Erosion on Pelton Turbines:A Review 被引量:1
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作者 Xinfeng Ge Jie Sun +8 位作者 Dongdong Chu Juan Liu Ye Zhou hui zhang Lei zhang huixiang Chen Kan Kan Maxime Binama Yuan Zheng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第3期36-62,共27页
The Pelton turbine has been widely used to develop high-head water resources with sediments because of its advantages in life cycle costs.When a flood or monsoon season occurs,the sediment concentration in the river i... The Pelton turbine has been widely used to develop high-head water resources with sediments because of its advantages in life cycle costs.When a flood or monsoon season occurs,the sediment concentration in the river increases suddenly,causing severe erosion to the nozzle,needle,and runner of Pelton turbines.After decades of development,researchers have developed practical engineering experience to reduce the sediment concentration of the flow through the turbine and ensure the safety and efficiency of power generation.Research on the mechanism of sediment erosion,development of anti-erosion materials,and establishment of erosion prediction models have attracted scholarly interest in recent years.Extensive research has been conducted to determine a complete and valuable syndication erosion model.However,owing to the complexity of the flow and wear mechanisms,the influence of specific parameters of erosion and the syndication effect is still difficult to determine.Computational fluid dynamics and erosion monitoring technology have also been evaluated and applied.This paper presents a comprehensive review of the erosion of Pelton turbines,some of the latest technical methods,and possible future development directions. 展开更多
关键词 Pelton turbine Sediment erosion Sediment erosion mechanism CFD The experimental method
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Revealing the grain size dependent hot workability and deformation mechanisms in a Mg-Zn-Y alloy 被引量:1
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作者 Ruiqing Lu Zhiming Xu +4 位作者 Fulin Jiang Shiwei Xu Dingfa Fu hui zhang Jie Teng 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第4期1461-1471,共11页
Despite the industrial significance of grain size for enhancing mechanical properties and formability,the in-depth deformation mechanisms at elevated temperature are still unclear.To investigate the functions of grain... Despite the industrial significance of grain size for enhancing mechanical properties and formability,the in-depth deformation mechanisms at elevated temperature are still unclear.To investigate the functions of grain size on hot workability and deformation mechanisms,three groups of Mg-1.2Zn-0.2Y alloy specimens with different grain sizes were hot compressed and then studied by combining constitutive model,processing map and microstructural observations.The results showed that the enhanced hot workability accompanying low deformation activation energy and small instability regime was obtained with refined grain size.During hot deformation,the decreased grain size in Mg1.2Zn-0.2Y alloy mainly improved the plastic deformation homogeneity,especially for the weakened local straining around grain boundaries.As a result,the dynamic recrystallization nucleation and texture development at lower strain level were influenced by the initial grain size.At higher strain magnitude,the growth and coarsening of dynamic recrystallized grains would further release strain localization and improve hot workability,while the texture was less impacted.Further,unlike the primary basal slip and deformation twinning in the specimen with coarse grain at low temperature,non-basal slips of dislocations were initiated with less deformation twins in the specimens with refined grain size. 展开更多
关键词 Mg-Zn-Y alloy Hot workability Plastic deformation Grain size TEXTURE
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Sensory-directed flavor analysis of key odorants compounds development of French fries and oils in the break-in,optimum and degrading frying stage 被引量:1
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作者 Lirong Xu Gangcheng Wu +3 位作者 Jianhua Huang hui zhang Qingzhe Jin Xingguo Wang 《Food Science and Human Wellness》 SCIE CSCD 2023年第1期140-150,共11页
The flavor is a decisive sensory characteristic that determines the popularity of French fries(FFs).During high-oleic rapeseed oil(RO)frying,the flavor development of FFs showed three noticeable stages including break... The flavor is a decisive sensory characteristic that determines the popularity of French fries(FFs).During high-oleic rapeseed oil(RO)frying,the flavor development of FFs showed three noticeable stages including break-in(3.5%-7.5%of total polar compounds(TPC)),optimum(7.5%-22.18%of TPC),and degrading stages(above 22.18%of TPC).Further,in order to distinguish the key aroma compounds in each stage,the FFs prepared in RO at TPC of 3.5%(FF4),14.5%(FF15),and 26.96%(FF27)and their relevant oils(RO4,RO15,RO27)were selected for sensory-directed analysis.The results revealed that the FF4 had low contents of(E,E)-2,4-decadienal(deep-fried odor)which also caused lower sensory score in FF4 sample.The higher contents of(E,E)-2,4-decadienal in FF15 induced its higher deep-fried odor.The FF27 had higher hexanoic acid(sweaty odor),heptanoic acid,nonanoic acid,benzene acetaldehyde(stale odor),and trans-4,5-epoxy-(E)-2-decenal(metallic odor)compared with FF4 and FF15,thus leading to the undesirable flavor of FF27.Moreover,the decrease of 2,5-dimethylpyrazine and 2-ethyl-6-methyl-pyrazine in FF27 induced the lower roasty flavor,which may also lead to the decline of the sensory score.Similarly,the higher contents of(E)-2-undecenal,hexanoic acid,heptanoic acid,and nonanoic acid in RO27 lead to increase its rancid score and thus lower the sensory score. 展开更多
关键词 French fries Frying stages OFF-FLAVOR Odor activity value Aroma recombination
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Prediction of Apple Fruit Quality by Soil Nutrient Content and Artificial Neural Network 被引量:1
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作者 Mengyao Yan Xianqi Zeng +5 位作者 Banghui zhang hui zhang Di Tan Binghua Cai Shenchun Qu Sanhong Wang 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第1期193-208,共16页
The effect of soil nutrient content on fruit yield and fruit quality is very important.To explore the effect of soil nutrients on apple quality we investigated 200 fruit samples from 40 orchards in Feng County,Jiangsu... The effect of soil nutrient content on fruit yield and fruit quality is very important.To explore the effect of soil nutrients on apple quality we investigated 200 fruit samples from 40 orchards in Feng County,Jiangsu Province.Soil mineral elements and fruit quality were measured.The effect of soil nutrient content on fruit quality was analyzed by artificial neural network(ANN)model.The results showed that the prediction accuracy was highest(R2=0.851,0.847,0.885,0.678 and 0.746)in mass per fruit(MPF),hardness(HB),soluble solids concentrations(SSC),titratable acid concentration(TA)and solid-acid ratio(SSC/TA),respectively.The sensitivity analysis of the prediction model showed that soil available P,K,Ca and Mg contents had the greatest impact on the quality of apple fruit.Response surface method(RSM)was performed to determine the optimum range of the available P,K,Ca,and Mg contents in orchards In Feng County,which were 10∼20 mg⋅kg^(−1),170∼200 mg⋅kg^(−1),1000∼1500 mg⋅kg^(−1),and 80∼200 mg⋅kg^(−1),respectively.The research also concluded that improving the content of available P and available Ca in orchard soil was crucial to improve apple fruit quality in Feng County,Jiangsu Province. 展开更多
关键词 APPLE soil nutrients fruit quality artificial neural network sensitivity analysis response surface methodology analysis
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钙钛矿太阳能电池的发展现状和未来趋势 被引量:1
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作者 胡浙鲁 冉晨鑫 +3 位作者 张辉 晁凌锋 陈永华 黄维 《Engineering》 SCIE EI CAS CSCD 2023年第2期15-19,共5页
1.Introduction Carbon neutrality is an important strategy to address the acute problems of resource and environmental constraints.Currently,afforestation,energy conservation,emissions reduction,and other measures have... 1.Introduction Carbon neutrality is an important strategy to address the acute problems of resource and environmental constraints.Currently,afforestation,energy conservation,emissions reduction,and other measures have been adopted to offset the total amount of carbon dioxide and other greenhouse gas emissions generated by countries,businesses,products,activities,or individuals,with the aim of finally achieving zero net emissions(Fig.1(a)). 展开更多
关键词 钙钛矿太阳能电池 现状和未来 finally
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The default mode network is affected in the early stage of simian immunodeficiency virus infection:a longitudinal study
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作者 Zhen-Chao Tang Jiao-Jiao Liu +6 位作者 Xue-Tong Ding Dan Liu Hong-Wei Qiao Xiao-Jie Huang hui zhang Jie Tian Hong-Jun Li 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第7期1542-1547,共6页
Acquired immune deficiency syndrome infection can lead to cognitive dysfunction represented by changes in the default mode network.Most recent studies have been cross-sectional and thus have not revealed dynamic chang... Acquired immune deficiency syndrome infection can lead to cognitive dysfunction represented by changes in the default mode network.Most recent studies have been cross-sectional and thus have not revealed dynamic changes in the default mode network following acquired immune deficiency syndrome infection and antiretroviral therapy.Specifically,when brain imaging data at only one time point are analyzed,determining the duration at which the default mode network is the most effective following antiretroviral therapy after the occurrence of acquired immune deficiency syndrome.However,because infection times and other factors are often uncertain,longitudinal studies cannot be conducted directly in the clinic.Therefore,in this study,we performed a longitudinal study on the dynamic changes in the default mode network over time in a rhesus monkey model of simian immunodeficiency virus infection.We found marked changes in default mode network connectivity in 11 pairs of regions of interest at baseline and 10 days and 4 weeks after virus inoculation.Significant interactions between treatment and time were observed in the default mode network connectivity of regions of interest pairs area 31/V6.R and area 8/frontal eye field(FEF).L,area 8/FEF.L and caudal temporal parietal occipital area(TPOC).R,and area 31/V6.R and TPOC.L.ART administered 4 weeks after infection not only interrupted the progress of simian immunodeficiency virus infection but also preserved brain function to a large extent.These findings suggest that the default mode network is affected in the early stage of simian immunodeficiency virus infection and that it may serve as a potential biomarker for early changes in brain function and an objective indicator for making early clinical intervention decisions. 展开更多
关键词 acquired immune deficiency syndrome analysis of variance antiretroviral therapy default mode network functional magnetic resonance imaging human immunodeficiency virus longitudinal study rhesus monkeys simian immunodeficiency virus SIV-mac239
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