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Lipid droplets in the nervous system:involvement in cell metabolic homeostasis
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作者 yuchen zhang Yiqing Chen +3 位作者 Cheng Zhuang Jingxuan Qi Robert Chunhua Zhao Jiao Wang 《Neural Regeneration Research》 SCIE CAS 2025年第3期740-750,共11页
Lipid droplets serve as primary storage organelles for neutral lipids in neurons,glial cells,and other cells in the nervous system.Lipid droplet formation begins with the synthesis of neutral lipids in the endoplasmic... Lipid droplets serve as primary storage organelles for neutral lipids in neurons,glial cells,and other cells in the nervous system.Lipid droplet formation begins with the synthesis of neutral lipids in the endoplasmic reticulum.Previously,lipid droplets were recognized for their role in maintaining lipid metabolism and energy homeostasis;however,recent research has shown that lipid droplets are highly adaptive organelles with diverse functions in the nervous system.In addition to their role in regulating cell metabolism,lipid droplets play a protective role in various cellular stress responses.Furthermore,lipid droplets exhibit specific functions in neurons and glial cells.Dysregulation of lipid droplet formation leads to cellular dysfunction,metabolic abnormalities,and nervous system diseases.This review aims to provide an overview of the role of lipid droplets in the nervous system,covering topics such as biogenesis,cellular specificity,and functions.Additionally,it will explore the association between lipid droplets and neurodegenerative disorders.Understanding the involvement of lipid droplets in cell metabolic homeostasis related to the nervous system is crucial to determine the underlying causes and in exploring potential therapeutic approaches for these diseases. 展开更多
关键词 Alzheimer's disease lipid droplet biogenesis lipid droplets lipid metabolism nervous system neurodegenerative disorders oxidative stress Parkinson's disease
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Robust and Trustworthy Data Sharing Framework Leveraging On-Chain and Off-Chain Collaboration 被引量:1
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作者 Jinyang Yu Xiao zhang +4 位作者 Jinjiang Wang yuchen zhang Yulong Shi Linxuan Su Leijie Zeng 《Computers, Materials & Continua》 SCIE EI 2024年第2期2159-2179,共21页
The proliferation of Internet of Things(IoT)systems has resulted in the generation of substantial data,presenting new challenges in reliable storage and trustworthy sharing.Conventional distributed storage systems are... The proliferation of Internet of Things(IoT)systems has resulted in the generation of substantial data,presenting new challenges in reliable storage and trustworthy sharing.Conventional distributed storage systems are hindered by centralized management and lack traceability,while blockchain systems are limited by low capacity and high latency.To address these challenges,the present study investigates the reliable storage and trustworthy sharing of IoT data,and presents a novel system architecture that integrates on-chain and off-chain data manage systems.This architecture,integrating blockchain and distributed storage technologies,provides high-capacity,high-performance,traceable,and verifiable data storage and access.The on-chain system,built on Hyperledger Fabric,manages metadata,verification data,and permission information of the raw data.The off-chain system,implemented using IPFS Cluster,ensures the reliable storage and efficient access to massive files.A collaborative storage server is designed to integrate on-chain and off-chain operation interfaces,facilitating comprehensive data operations.We provide a unified access interface for user-friendly system interaction.Extensive testing validates the system’s reliability and stable performance.The proposed approach significantly enhances storage capacity compared to standalone blockchain systems.Rigorous reliability tests consistently yield positive outcomes.With average upload and download throughputs of roughly 20 and 30 MB/s,respectively,the system’s throughput surpasses the blockchain system by a factor of 4 to 18. 展开更多
关键词 On-chain and off-chain collaboration blockchain distributed storage system hyperledger fabric IPFS cluster
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Unlocking fast Li-ion transport in micrometer-sized Mn-based cation-disordered rocksalt cathodes
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作者 yuchen zhang Hao Chen +5 位作者 Runze Yu Wei Yang Jia He Haoyang Li Xianhu Sun Zhengyan Lun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第12期645-653,共9页
The development of cation-disordered rocksalt(DRX)cathodes has garnered worldwide attention due to their high capacity,broad chemical space and excellent structural flexibility.However,their low intrinsic Li-ion condu... The development of cation-disordered rocksalt(DRX)cathodes has garnered worldwide attention due to their high capacity,broad chemical space and excellent structural flexibility.However,their low intrinsic Li-ion conductivity necessitates extensive particle pulverization,typically achieved through ball-milling process,which impedes large-scale production.In this work,we present a proton-exchange assisted strategy to activate the Li-ion transport in Mn-based DRX cathodes.Short-range spinel-like ordering is observed to form within the DRX matrix after the post treatment,which significantly enhances the intrinsic Li ion mobility.Notably,more than 280 mAh g^(-1)discharge capacity can be delivered at a slow rate from micrometer-sized particles with an overall disordered cation arrangement,which retains more than150 m Ah g^(-1)when cycled at a very high rate of 2000 mA g^(-1).Furthermore,we also demonstrate that the electrochemical performance of the post-treated cathodes can be further optimized by fine-tuning the reaction parameters. 展开更多
关键词 Cation-disordered rocksalt cathodes Partially-disordered spinel PROTON-EXCHANGE Short-range order
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基于logistic模型的农户意愿对宅基地退出的影响——以无锡市为例 被引量:3
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作者 张宇辰 黄贤金 +1 位作者 陈志刚 赵小风 《土地经济研究》 2015年第1期24-36,共13页
研究目的:在对无锡市锡山区东港镇三联村、港东村和惠山区堰桥街道村前村的96户农户问卷调查的基础上,通过构建logistic模型分析农户意愿对宅基地退出的影响。研究方法:问卷调查法、logistic模型。研究结果:农民受教育程度、家中老人小... 研究目的:在对无锡市锡山区东港镇三联村、港东村和惠山区堰桥街道村前村的96户农户问卷调查的基础上,通过构建logistic模型分析农户意愿对宅基地退出的影响。研究方法:问卷调查法、logistic模型。研究结果:农民受教育程度、家中老人小孩数量、宅基地面积对农民宅基地退出意愿有正向影响;年龄、房屋建造成本、现居住满意度对农民宅基地退出意愿有负向影响;性别、是否从事非农工作、家庭人口、家庭年收入、外出务工人数、房屋面积、房屋年限、是否购买商品房等因素对农民宅基地退出意愿没有显著影响;三联村宅基地退出意愿明显低于港东村和村前村。研究结论:农户宅基地退出意愿受农户个体、农户家庭和居住条件等多个方面的影响。 展开更多
关键词 宅基地 农户退出意愿 LOGISTIC模型
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Selinexor, Carfilzomib, Pomalidomide, and Dexamethasone as a Salvage Regimen for Refractory and Relapsed Multiple Myeloma with Plasma-Cell Leukemia Transformation: A Case Report and Literature Review 被引量:1
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作者 Yanfang zhang Chen Ying +1 位作者 yuchen zhang Jianchuan Deng 《Case Reports in Clinical Medicine》 2022年第7期245-252,共8页
Refractory and relapsed multiple myeloma (RRMM) with plasma-cell leukemia (PCL) transformation is highly aggressive and resistant to conventional therapy. Novel therapeutics are needed for RRMM-transformed PCL. Seline... Refractory and relapsed multiple myeloma (RRMM) with plasma-cell leukemia (PCL) transformation is highly aggressive and resistant to conventional therapy. Novel therapeutics are needed for RRMM-transformed PCL. Selinexor [an oral exportin 1 (XPO1) inhibitor], carfilzomib (a second-in-class proteasome inhibitor), pomalidomide (third generation of immunomodulatory drug) are usually used for RRMM, but there are no reports on their application in PCL transformation. We describe a 62-year-old male initially diagnosed with MM IgD-lambda type with complex karyotype and extramedullary plasmacytoma in 2020, and relapsed after five months of autologous stem cell transplantation. Despite the use of various therapies, the patient rapidly developed into PCL over a 4-month period. The patient was started on selinexor, carfilzomib, pomalidomide, and dexamethasone (XKPd) combination as a salvage regimen in July 2021. He achieved fast response in first cycle. Then, he fulfilled third cycle of consolidation treatment and got four-month remission. The success of XKPd therapy in achieving a good response suggests its utility in RRMM transformed-PCL patients, who have exhausted various combinations of drug regimens and have historically poor survival outcomes. 展开更多
关键词 Selinexor Carfilzomib Multiple Myeloma Plasma Cell Leukemia
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Synthesis, Characterization and Properties of Polymeric p-Benzoyl-4,4'-Diaminobenzoylaniline
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作者 Chundong Mi Menglan Yuan +2 位作者 yuchen zhang He Li Qianfeng zhang 《Journal of Materials Science and Chemical Engineering》 2023年第8期33-42,共19页
An aromatic polyamide was synthesized by low-temperature poly-condensation reaction from terephthaloyl chloride and 4,4'-diaminobenzanilide (4,4'-DABA). The synthesized polyamide had a characteristic peak of c... An aromatic polyamide was synthesized by low-temperature poly-condensation reaction from terephthaloyl chloride and 4,4'-diaminobenzanilide (4,4'-DABA). The synthesized polyamide had a characteristic peak of carbon atoms in the amide group at 166 ppm, which was demonstrated by the solid nuclear magnetic resonance carbon spectrum. It was shown to be the stretching vibration absorption peak of the amide N-H bond at 3342 cm<sup>−1</sup> by Fourier infrared (FT-IR) spectroscopy. It was obtained that the energy band near 1100 - 1276 cm<sup>−1</sup> belongs to the absorption peak of the para-substituted benzene ring and the band near 2977 cm<sup>−1</sup> was the C-H stretching vibration peak of the benzene ring by Raman spectroscopy. The molecular structure of the synthesized polyamide compound was confirmed by FT-IR, Raman, and solid <sup>13</sup>C-NMR spectroscopies. It was proved that the polymer is stable up to 300˚C and has a relatively high stability by the thermogravimetric analysis. It was also confirmed by the fluorescence spectrum that it has a strong blue fluorescence near 420 nm. The morphological characteristics of the polymer were further demonstrated by electron scanning electron microscopy (SEM). The properties of polymeric p-benzoyl-4,4'-diaminobenzoyl-aniline were found to emit strong blue fluorescence and have good thermal stability, making it a promising functional material for fluorescence in the blue region with potential for large-scale applications. 展开更多
关键词 Aromatic Polyamide Thermogravimetric Analysis Heat Resistance Polymeric p-Benzoyl-4 4'-Diaminobenzoylaniline
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Trade Benefits and Environmental Costs of GVCS: A Case Study of the BRICS
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作者 Xiaohong Yu Jiajia Fan +3 位作者 Yihang Luo Xiaoyuan Zhu yuchen zhang Xiaofei Long 《American Journal of Climate Change》 2023年第1期39-57,共19页
As the international trading system has developed with the division of Global value Chains (GVCS), the export trade of Brazil, Russia, India, China, and South Africa (BRICS) has grown rapidly. The resulting growth of ... As the international trading system has developed with the division of Global value Chains (GVCS), the export trade of Brazil, Russia, India, China, and South Africa (BRICS) has grown rapidly. The resulting growth of carbon emissions has drawn wide attention from the international community, necessitating the comparison of the trade benefits and environmental costs of the BRICS participation in GVCS. Based on the Eora database, this paper constructs a decomposition framework for the calculation of export value-added and embodied carbon, based on a multi-region input-output (MRIO) model. The trade benefits and environmental costs paid by the BRICS’ total exports from 1990 to 2015 were measured and the imbalance was analyzed, along with the causes. The results show that the main value-added and carbon embodied in the BRICS’ exports originate from their own countries, and the domestic value-added content of the BRICS’ exports decreased while the foreign value-added content increased. 展开更多
关键词 BRICS GVCS Export Added Value Carbon Embodied in Export Source of Imbalance between the Trade Benefits and Environmental Costs
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Synthesis, Characterization and Properties of Polymeric p-Benzoyl-4,4'-Diaminobenzoylaniline
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作者 Chundong Mi Menglan Yuan +2 位作者 yuchen zhang He Li Qianfeng zhang 《Journal of Modern Physics》 2023年第8期33-42,共26页
An aromatic polyamide was synthesized by low-temperature poly-condensation reaction from terephthaloyl chloride and 4,4'-diaminobenzanilide (4,4'-DABA). The synthesized polyamide had a characteristic peak of c... An aromatic polyamide was synthesized by low-temperature poly-condensation reaction from terephthaloyl chloride and 4,4'-diaminobenzanilide (4,4'-DABA). The synthesized polyamide had a characteristic peak of carbon atoms in the amide group at 166 ppm, which was demonstrated by the solid nuclear magnetic resonance carbon spectrum. It was shown to be the stretching vibration absorption peak of the amide N-H bond at 3342 cm<sup>−1</sup> by Fourier infrared (FT-IR) spectroscopy. It was obtained that the energy band near 1100 - 1276 cm<sup>−1</sup> belongs to the absorption peak of the para-substituted benzene ring and the band near 2977 cm<sup>−1</sup> was the C-H stretching vibration peak of the benzene ring by Raman spectroscopy. The molecular structure of the synthesized polyamide compound was confirmed by FT-IR, Raman, and solid <sup>13</sup>C-NMR spectroscopies. It was proved that the polymer is stable up to 300˚C and has a relatively high stability by the thermogravimetric analysis. It was also confirmed by the fluorescence spectrum that it has a strong blue fluorescence near 420 nm. The morphological characteristics of the polymer were further demonstrated by electron scanning electron microscopy (SEM). The properties of polymeric p-benzoyl-4,4'-diaminobenzoyl-aniline were found to emit strong blue fluorescence and have good thermal stability, making it a promising functional material for fluorescence in the blue region with potential for large-scale applications. 展开更多
关键词 Aromatic Polyamide Thermogravimetric Analysis Heat Resistance Polymeric p-Benzoyl-4 4'-Diaminobenzoylaniline
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Acupuncture activates signal transduction pathways related to brain-tissue restoration after ischemic injury 被引量:10
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作者 Haomei Tian Hong zhang +4 位作者 Junbao Zhu Juan zhang Hening Cai yuchen zhang Chutao Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第24期1866-1872,共7页
A middle cerebral artery occlusion-model was established in rats using the improved thread embolism method.Rats were treated with acupuncture at either Dazhui(DU14),Renzhong(DU26), Baihui(DU20),or a non-meridian... A middle cerebral artery occlusion-model was established in rats using the improved thread embolism method.Rats were treated with acupuncture at either Dazhui(DU14),Renzhong(DU26), Baihui(DU20),or a non-meridian point.Detection with protein-chip technology showed that the level of protein phosphorylation in both groups was upregulated or downregulated depending on the signaling pathway compared with the model group that did not receive acupuncture.Analysis of proteins showing downregulated phosphorylation revealed that five signaling pathways were activated in the acupuncture-treatment group,while only two were activated in the acupuncture-control group.In contrast,analysis of proteins showing upregulated phosphorylation revealed only one pathway was activated in the acupuncture-treatment group,whereas four pathways were activated in the acupuncture-control group.Furthermore,the number of activated proteins in the acupuncture-treatment group was not only higher than the acupuncture-control group,but unlike the acupuncture-control group,the majority of activated proteins were key proteins in the signaling pathways.Our findings indicate that acupuncture at specific points can activate multiple signaling pathways to promote the restoration of brain tissue following ischemic injury,and that this is based on a combination of effects resulting from multiple pathways,targets,and means. 展开更多
关键词 ACUPUNCTURE cerebral ischemia DAZHUI Baihui RENZHONG protein-chip technology signal-transduction pathways nerve injury brain injury ischemic injury neural regeneration
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CNN coal and rock recognition method based on hyperspectral data 被引量:3
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作者 Jianjian Yang Boshen Chang +3 位作者 yuchen zhang Wenjie Luo Shirong Ge Miao Wu 《International Journal of Coal Science & Technology》 EI CAS CSCD 2022年第5期59-70,共12页
Aiming at the problem of coal gangue identifcation in the current fully mechanized mining face and coal washing,this article proposed a convolution neural network(CNN)coal and rock identifcation method based on hypers... Aiming at the problem of coal gangue identifcation in the current fully mechanized mining face and coal washing,this article proposed a convolution neural network(CNN)coal and rock identifcation method based on hyperspectral data.First,coal and rock spectrum data were collected by a near-infrared spectrometer,and then four methods were used to flter 120 sets of collected data:frst-order diferential(FD),second-order diferential(SD),standard normal variable transformation(SNV),and multi-style smoothing.The coal and rock refectance spectrum data were pre-processed to enhance the intensity of spectral refectance and absorption characteristics,as well as efectively remove the spectral curve noise generated by instrument performance and environmental factors.A CNN model was constructed,and its advantages and disadvantages were judged based on the accuracy of the three parameter combinations(i.e.,the learning rate,the number of feature extraction layers,and the dropout rate)to generate the best CNN classifer for the hyperspectral data for rock recognition.The experiments show that the recognition accuracy of the one-dimensional CNN model proposed in this paper reaches 94.6%.Verifcation of the advantages and efectiveness of the method were proposed in this article. 展开更多
关键词 Hyperspectral data Data pre-processing 1D-CNN Coal gangue identifcation
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Routing Loop Audit Mechanism Based on SDN 被引量:2
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作者 Tao Yu yuchen zhang +2 位作者 Diyue Chen Hongyan Cui Jilong Wang 《China Communications》 SCIE CSCD 2019年第7期96-108,共13页
Routing loops can cause packet loss and long delay problems in the traditional network. Even in future networks – Software-Defined Networks, with loop-free implementation mechanism, it still suffers loop problems. In... Routing loops can cause packet loss and long delay problems in the traditional network. Even in future networks – Software-Defined Networks, with loop-free implementation mechanism, it still suffers loop problems. In this paper, we propose an architecture to solve the loop problem in SDN. Unlike the existing passive routing loop detection algorithm, this algorithm processes based on the SDN loop-free characteristic, by auditing third-party network forwarding rules’ modification requests to avoids loop generation, thus avoid the network loop problems. Testbed is built to simulate our proposed algorithm. The evaluation shows that the loop audit algorithm proposed in this paper has better performance in extra spatial utilization and smaller number of extra interactions between SDN controller and switches. 展开更多
关键词 software-defined network Open- Flow ROUTING LOOPS FORWARDING REQUEST
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Effects of electron-and hole-current hysteresis on trap characterization in organo-inorganic halide perovskite 被引量:1
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作者 Fan Wu Sally Mabrouk +5 位作者 Miaomiao Han Yanhua Tong Tiansheng zhang yuchen zhang Raja Sekhar Bobba Quinn Qiao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第1期414-420,I0010,共8页
Charge trap density and carrier mobility of perovskite materials are the critical properties of perovskite solar cells.The space charge limited current(SCLC)method,which measures a dark current–voltage(I-V)curve of a... Charge trap density and carrier mobility of perovskite materials are the critical properties of perovskite solar cells.The space charge limited current(SCLC)method,which measures a dark current–voltage(I-V)curve of a single-carrier device has found extensive use for studying the trap density and charge carrier mobility in perovskite materials.Herein,it was found that the electron-and hole-current in organo-lead perovskite-based single-carrier device undergoes significant hysteresis under forward and reverse scanning due to the mobile ions.In addition,it was also observed that measuring history has a detrimental effect on hysteresis resulting in possible overestimation or underestimation of the extracted electrical values from the SCLC measurement.In the forward/reverse scanning process,the mobile ionic defects enhance/shield the charge in the traps due to ionic charging/discharging,thereby increasing/reducing the interface barrier and net charge in the I-V scanning,which in turn affects the determination of transport properties of the carrier.These results raise quite a few doubts over the direct application of classical SCLC measurements for the accurate characterization of intrinsic transport properties of the mixed ionicelectronic perovskite. 展开更多
关键词 Organo-lead perovskite Ionic defects Space-charge-limited-current Trap density Mobility
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Pd(100)氧化表面上低温丙烷氧化的活性相研究
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作者 徐美佳 张宇琛 +4 位作者 朱一帆 李昌林 吴子昂 周雄 吴凯 《物理化学学报》 SCIE CAS CSCD 北大核心 2023年第10期11-18,共8页
钯作为汽车尾气处理的三效催化剂的关键成分,在烷烃的完全氧化和CO低温氧化中扮演着重要催化角色。在富氧环境下,钯表面通常会形成薄的氧化物层。为了揭示钯表面上烷烃完全氧化的活性相,我们对Pd(100)表面氧化过程及其对丙烷氧化的活性... 钯作为汽车尾气处理的三效催化剂的关键成分,在烷烃的完全氧化和CO低温氧化中扮演着重要催化角色。在富氧环境下,钯表面通常会形成薄的氧化物层。为了揭示钯表面上烷烃完全氧化的活性相,我们对Pd(100)表面氧化过程及其对丙烷氧化的活性相进行了详细研究。实验结果表明,在不同氧化条件下,Pd(100)表面依次形成了三种单层氧化相,即(2×2)-O、(5×5)-PdO和(√5×√5)R27°-PdO,它们的O覆盖度分别为0.25单层,0.56单层和0.8单层。值得注意的是,(5×5)-PdO结构首次得到了高分辨扫描隧道显微镜成像的确认。实验发现该结构呈现出典型的手性特征,两种手性对映体结构也可在实验中观察到。根据高分辨原子成像,我们提出了新的(5×5)-PdO结构模型。(5×5)-PdO结构的手性特征在手性催化等领域中可能有着重要意义。热分解实验发现(5×5)-PdO结构热分解形成(√5×√5)R27°-PdO和(2×2)-O结构,而(√5×√5)R27°-PdO热分解产生(2×2)-O。该结果表明这些氧化相的热稳定性次序为(2×2)-O>(√5×√5)R27°-PdO>(5×5)-PdO。随后我们对比研究了这三种氧化相在低温丙烷氧化方面的催化活性。结果表明,只有(√5×√5)R27°-PdO可以在接近室温条件下催化丙烷氧化,而(√5×√5)R27°-PdO出现了大量氧缺陷,且形成还原的(2×2)-O相。程序升温脱附谱测到了完全氧化产物H_(2)O和CO_(2),在285和315 K出现两个主要反应温区。(2×2)-O和(5×5)-PdO相则无明显的催化活性。(√5×√5)R27°-PdO相的优异氧化活性可能与(√5×√5)R27°-PdO结构中较高的O密度相关,即结构中较活泼的O物种。本研究表明(√5×√5)R27°-PdO为丙烷低温氧化中的活性相。这些有助于人们理解三效催化剂的工作机制,对于高效低温三效催化剂的研发具有重要意义。 展开更多
关键词 氧化钯 手性氧化物 丙烷低温氧化 扫描隧道显微镜
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A Brief Analysis of the Application of Situational Teaching Method in Primary School Music Class 被引量:1
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作者 yuchen zhang 《Journal of Contemporary Educational Research》 2020年第10期62-65,共4页
Music situational teaching method aims to mobilize the students’thoughts in a natural state so as to enhance the attractiveness and efficiency of music classes.In the process of this method,some specific situational ... Music situational teaching method aims to mobilize the students’thoughts in a natural state so as to enhance the attractiveness and efficiency of music classes.In the process of this method,some specific situational are designed according to the characteristics of music and under the guidance of psychology,methodology,pedagogy and other theories,and various sensory organs are employed.Different from traditional teaching method,situational teaching method creates learning situational for students,which is consistent with the characteristics of primary school students’physical and mental development and maximizes students’experience and feeling of music. 展开更多
关键词 Music situational teaching method Primary school music education Music class
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深圳市南山区社区居民高血压患病状况及危险因素分析
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作者 张玉琛 陈鹰 何计国 《食品与营养科学》 2018年第4期303-310,共8页
目的:了解深圳市南山区2016~2018年社区居民高血压的患病状况及其危险因素,结合该地区人口构成和生活方式的特殊性,有针对性地制定社区高血压的防治策略。方法:分析资料来源于2016~2018三年深圳市南山区社区体检数据资料,以比较不同特... 目的:了解深圳市南山区2016~2018年社区居民高血压的患病状况及其危险因素,结合该地区人口构成和生活方式的特殊性,有针对性地制定社区高血压的防治策略。方法:分析资料来源于2016~2018三年深圳市南山区社区体检数据资料,以比较不同特征人群高血压患病率。用多元Logistic回归综合分析高血压危险因素,用OR值表明不同因素影响程度。所有统计分析都是在SPSS 22.0统计软件中完成。结果:深圳市南山区参与体检居民高血压患病率为37.5%,高于广东省水平且稍高于全国水平。男性高血压患病率为38.9%,女性为36.5%,男性患病率高于女性(χ2 = 103.258, P 2 = 13,697.071, P 2 = 13,296.238, P 2 = 2487.425, P 2 = 2451.140, P 2 = 1349.515, P 2 = 1328.383, P <0.001)。多因素Logistic回归分析结果显示,性别、年龄 ≥ 50岁、超重、肥胖、糖尿病是高血压的危险因素。结论:2016~2018年深圳市南山区18岁以上居民高血压患病率较高。性别、年龄 ≥ 50岁、超重、肥胖、糖尿病是高血压的危险因素。应结合该地区人群特点的特殊性有针对性地制定防治策略。 展开更多
关键词 南山区 高血压 患病 危险因素
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Preload-responsive adhesion of microfibre arrays to rough surfaces
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作者 yuchen zhang Linghui HE 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第2期155-160,共6页
Adhesion of bio-inspired microfibre arrays to a rough surface is studied theoretically. The array consists of vertical elastic rods fixed on a rigid backing layer, and the surface is modeled by rigid steps with a norm... Adhesion of bio-inspired microfibre arrays to a rough surface is studied theoretically. The array consists of vertical elastic rods fixed on a rigid backing layer, and the surface is modeled by rigid steps with a normally distributed height. Analytical expressions are obtained for the adhesion forces in both the approach and retraction processes. It is shown that, with the increasing preload, the pull-off force increases at first and then attains a plateau value. The results agree with the previous experiments and are expected helpful in adhesion control of the array in practical applications. 展开更多
关键词 fibrillar adhesion rough surface PRELOAD pull-off force
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Perspective for aggregation-induced delayed fluorescence mechanism:A QM/MM study
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作者 Jie Liu Jianzhong Fan +3 位作者 Kai zhang yuchen zhang Chuan-Kui Wang Lili Lin 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第8期531-537,共7页
To enhance the potential application of thermally activated delayed fluorescence(TADF)molecular materials,new functions are gradually cooperated to the TADF molecules.Aggregation induced emission can effectively solve... To enhance the potential application of thermally activated delayed fluorescence(TADF)molecular materials,new functions are gradually cooperated to the TADF molecules.Aggregation induced emission can effectively solve the fluorescence quenching problem for TADF molecules in solid phase,thus aggregation-induced delayed fluorescence(AIDF)molecules were recently focused.Nevertheless,their luminescent mechanisms are not clear enough.In this work,excited state properties of an AIDF molecule DMF-BP-DMAC[reported in Chemistry-An Asian Journal 14828(2019)]are theoretically studied in tetrahydrofuran(THF)and solid phase.For consideration of surrounding environment,the polarizable continuum method(PCM)and the combined quantum mechanics and molecular mechanics(QM/MM)method were applied for solvent and solid phase,respectively.Due to the increase of the transition dipole moment and decrease of the energy difference between the first single excited state(S1)and the ground state(S0),the radiative rate is increased by about 2 orders of magnitude in solid phase.The energy dissipation of the non-radiative process from S1 to S0 is mainly contributed by low-frequency vibrational modes in solvent,and they can be effectively suppressed in aggregation,which may lead to a slow non-radiation process in solid phase.Both factors would induce enhanced luminescence efficiency of DMF-BP-DMAC in solid phase.Meanwhile,the small energy gap between S1 and triplet excited states results in high reverse intersystem crossing(RISC)rates in both solvent and solid phase.Therefore,TADF is confirmed in both phases.Aggregation significantly influences both the ISC and RISC processes and more RISC channels are involved in solid state.The enhanced delayed fluorescence should be induced by both the enhanced fluorescent efficiency and ISC efficiency.Our calculation provides a reasonable explanation for experimental measurements and helps one to better understand the luminescence mechanism of AIDF molecules. 展开更多
关键词 thermally activated delayed fluorescence aggregation-induced delayed fluorescence the combined quantum mechanics and molecular mechanics method
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Application of a parameter-shifted grey wolf optimizer for earthquake dynamic rupture inversion
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作者 Zhenguo zhang yuchen zhang 《Earthquake Science》 2021年第6期507-521,共15页
Global optimization is an essential approach to any inversion problem.Recently,the grey wolf optimizer(GWO)has been proposed to optimize the global minimum,which has been quickly used in a variety of inv-ersion proble... Global optimization is an essential approach to any inversion problem.Recently,the grey wolf optimizer(GWO)has been proposed to optimize the global minimum,which has been quickly used in a variety of inv-ersion problems.In this study,we proposed a parameter-shifted grey wolf optimizer(psGWO)based on the conven-tional GWO algorithm to obtain the global minimum.Com-pared with GWO,the novel psGWO can effectively search targets toward objects without being trapped within the local minimum of the zero value.We confirmed the effectiveness of the new method in searching for uniform and random objectives by using mathematical functions released by the Congress on Evolutionary Computation.The psGWO alg-orithm was validated using up to 10,000 parameters to dem-onstrate its robustness in a large-scale optimization problem.We successfully applied psGWO in two-dimensional(2D)synthetic earthquake dynamic rupture inversion to obtain the frictional coefficients of the fault and critical slip-weakening distance using a homogeneous model.Furthermore,this alg-orithm was applied in inversions with heterogeneous dist-ributions of dynamic rupture parameters.This implementation can be efficiently applied in 3D cases and even in actual earthquake inversion and would deepen the understanding of the physics of natural earthquakes in the future. 展开更多
关键词 grey wolf optimizer dynamic rupture inversion non-linear inversion earthquake rupture.
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Reliability and validity of the hidden hunger assessment scale in China-revised for high school students
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作者 Ning zhang Minao Wang +6 位作者 yuchen zhang Huake Cao Yang Yang Yuhang Shi Yang Pei Feixiang Yang Yinan Du 《Global Health Journal》 2023年第2期110-116,共7页
Objective:Hidden hunger remains a severe public health problem that affects millions of people worldwide.In China,challenges related to dietary imbalance and hidden hunger persist.Micronutrient inadequacy deserves mor... Objective:Hidden hunger remains a severe public health problem that affects millions of people worldwide.In China,challenges related to dietary imbalance and hidden hunger persist.Micronutrient inadequacy deserves more attention among adolescents,given its vital role in their growth and development;however,this problem appears to have been largely ignored.High school students,in particular,are often at a high risk of hidden hunger but have limited assessment tools available.Therefore,this study aims to revise the hidden hunger assessment scale for high school students(HHAS-HSS)in China and assess its reliability and validity.Methods:Based on a literature review,expert consultation,pre-experiment,and formal survey,a hidden hunger assessment scale was revised for high school students.The formal survey involved 9336 high school students in 11 of the 16 cities in Anhui Province,China,and 9038 valid questionnaires were collected and included in the analysis.The item analysis,internal consistency reliability,test-retest reliability,content validity,exploratory factor analysis,and confirmatory factor analysis of the HHAS-HSS were examined.Results:The HHAS-HSS included a total of 4 dimensions and 12 items:"vegetables and food diversity"(three items),"fruits and dairy products"(three items),"micronutrient-dense foods"(four items),and"health condition and eating habits"(two items).The results showed a Cronbach's alpha of 0.758,a split-half reliability of 0.829,and a test-retest reliability of o.793,indicating good internal consistency.Using the Bartlett's test and Kaiser-Meyer-Olkin test(KMO)to test the exploratory factor analysis presented a four-factor model of the HHAS-HSS,the KMO0 value was 0.820(P<0.001),which indicated the possibility for factor confirmatory factor analysis.Using the maximum variance rotation method,four factors were obtained,and the cumulative variance explained rate was 57.974%.Confirmatory factor analysis also supported the division of the scale into four dimensions,and the fitting indices were x^(2)=1417.656,x^(2)/df=29.534,goodness-of-fit index=0.974,adjusted goodnessof-fit index=0.958,parsimonious goodness-of-fit index=0.600,normed fit index=0.938,incremental fit index=0.940,Tucker-Lewis index=0.917,comparative fit index=0.939,and root mean square error of approximation=0.056.Except for x^(2)/df,all the indices reached the fitting standard,and the above results showed that the construct validity of the scale reached an acceptable level.Conclusions:The HHAS-HSS has good validity and reliability for Chinese high school students.It is a convenient self-report measure of hidden hunger risk. 展开更多
关键词 Hidden hunger Reliability and validity Assessment scale High school student MICRONUTRIENTS
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Paleoenvironment evolution and organic matter enrichment mechanisms in the first member of the Qingshankou Formation,Songliao Basin,China
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作者 Ying LI Min WANG +8 位作者 Yu YAN Xin WANG Jinyou zhang Xuefeng BAI yuchen zhang Jiaheng XUE Junsheng FEI Lianbin zhang Guojun WANG 《Frontiers of Earth Science》 SCIE CSCD 2024年第2期364-383,共20页
Organic matter is the basis for oil and gas generation,and the depositional environment controls its enrichment.The first member of the Qingshankou Formation(K_(2)qn^(1))in Songliao Basin has a thick organic-rich shal... Organic matter is the basis for oil and gas generation,and the depositional environment controls its enrichment.The first member of the Qingshankou Formation(K_(2)qn^(1))in Songliao Basin has a thick organic-rich shale and so is an important target section for shale oil exploration and development.In the Gulong Sag,shale samples from this unit were collected over the full length of the section.The characterization of the environments of deposition(EOD)of K_(2)qn^(1)was improved by utilizing lithological characteristics,thin section observations,elemental compositions,and organic carbon concentrations.Combined with the normalization coefficients proposed in this paper,an organic matter correlation model was established to elucidate the factors that influence organic matter enrichment.From the bottom to the top of K2qn1,the lake depth gradually becomes shallower,the primary productivity first decreases and then increases,the reducing conditions become stronger and then weaker,the water salinity gradually decreases,the climate first becomes semi-humid and then warm and humid,and the input of terrigenous debris first decreases and then increases.A major marine transgression at the base of the K_(2)qn^(1)᾽s brought in nutrients to increase primary productivity,and the density-stratified reducing environment preserved and enriched organic matter.High primary productivity occurred during the middle of the deposition of the K_(2)qn^(1),while terrigenous input is low.Organic matter is preserved in reduced deep lake environments,resulting in organic matter-rich black shale.The lake became shallower,and the salinity decreased in the upper part of K_(2)qn^(1).Benthic organisms rapidly multiplied,consuming large amounts of oxygen and destroying the previously depositional environment,resulting in a reducing environment disturbed by benthic organisms with poor preservation conditions and the lowest organic matter content. 展开更多
关键词 major and trace elements paleoenvironment evolution OM enrichment mechanism lacustrine shale Songliao Basin Qingshankou Formation
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