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Low temperature synthesis of high-entropy(Y_(0.2)Yb_(0.2)Sm_(0.2)Eu_(0.2)Er_(0.2))_(2)O_(3)nanofibers by a novel electrospinning method

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Journal of Materials Science & Technology 2022年第8期103卷 215-220页

作者： yan Xing Wenqing Dan Yicun Fan Xing’ao Li New Energy Technology Engineering Lab of Jiangsu Province School of ScienceNanjing University of Posts&Telecommunications(NUPT)Nanjing 210023China

High-entropy ceramics(HECs)show outstanding properties such as amorphous-like thermal conductivities,colossal dielectric constant,superionic conductivity,enhanced electromagnetic wave absorption ability,super hardness and strength,which are promising for structural and functional ***,the high synthesis temperature has become the bottleneck that hinders the scale-up production and practical applications of *** is thus appealing to develop a novel low-temperature process for the synthesis of *** demonstrate the feasibility of low-temperature synthesis,herein,an electrospinning method has been utilized,for the first time,for the synthesis of high-entropy(Y_(0.2)Yb_(0.2)Sm_(0.2)Eu_(0.2)Er_(0.2))_(2)O_(3)*** has been found that after electrospinning from liquid precursors single phase(Y_(0.2)Yb_(0.2)Sm_(0.2)Eu_(0.2)Er_(0.2))_(2)O_(3) solid solution with bixbyite structure can be formed by calcining at a temperature as low as 500℃,which is at least about 1000℃ lower than that used in the solid-state synthesis *** as-prepared(Y_(0.2)Yb_(0.2)Sm_(0.2)Eu_(0.2)Er_(0.2))_(2)O_(3) nanofibers are continuous and uniform with a smooth surface and a small diameter of 150 *** is also intriguing that the average grain size of(Y_(0.2)Yb_(0.2)Sm_(0.2)Eu_(0.2)Er_(0.2))_(2)O_(3) is only about 10 nm,which is much smaller than that in the solid-state synthesized *** addition,all the elements are homogeneously distributed along the *** work demonstrates that high-entropy ceramic nanofibers can be synthesized from liquid precursors at low temperatures through a simple,efficient,and low-cost electrospinning method,which opens up a new avenue for the low-temperature synthesis of HECs.

关键词： High-entropy ceramics Nanofibers Electrospinning Rare earth metal oxides Synthesis

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基于CFD的新型高速艇艇型静水性能研究

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舰船科学技术 2020年第7期42卷 70-73页

作者：李岩柳存根上海交通大学船舶与海洋工程国家重点实验室上海200240 高新船舶与深海开发装备协同创新中心上海200240

深V型艇作为一种优异的改良船型,明显改善了舰船的耐波性及航向稳定性,但由于横向剖面尖瘦,舱室容积相对较小,不利于武器设备的布置,而三体滑行艇作为新型艇型,拥有诸多优势,国内仍处于研究阶段,为了了解这种艇型相对于传统深V艇的优势... 详细信息

深V型艇作为一种优异的改良船型,明显改善了舰船的耐波性及航向稳定性,但由于横向剖面尖瘦,舱室容积相对较小,不利于武器设备的布置,而三体滑行艇作为新型艇型,拥有诸多优势,国内仍处于研究阶段,为了了解这种艇型相对于传统深V艇的优势大小,利用CFD软件从静水性能方向进行分析研究,从阻力、浮态、兴波及艇底压力分布角度来分析其优劣势,结果表明三体艇仅在Fr?<4.5其阻力及浮态劣于深V艇,其他均处于优势,且随着航速提高优势将继续扩大。

关键词：深V艇三体滑行艇数值模拟静水性能船型对比

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Phase evolution in(1x)(Na_(0.5)Bi_(0.5))TiO_(3)-xSrTiO_(3) solid solutions:A study focusing on dielectric and ferroelectric characteristics

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Journal of Materiomics 2020年第4期6卷 677-691页

作者： Gang Liu Jia Dong Leiyang Zhang yan yan Ruiyi Jing Li Jin School of Materials and Energy Southwest UniversityChongqing400715China Electronic Materials Research Laboratory Key Laboratory of the Ministry of Education&International Center for Dielectric ResearchSchool of Electronic Science and EngineeringFaculty of Electronic and Information EngineeringXi’an Jiaotong UniversityXi’an710049China

In the present work,the nature of phase evolution of(1x)(Na_(0.5)Bi_(0.5))TiO_(3)-xSrTiO_(3)(NBT-xST)solid solutions with x of 0e0.6 is revealed by characterizing the dielectric and ferroelectric *** unique dielectric anomalies associated with high-temperature nanoregions(PNRs)in the ergodic relaxor(ER)state and low-temperature PNRs in the nonergodic relaxor(NR)state are *** temperatures,including TB,TRT*,Tm,Td and TT*,are determined in fresh and poled states on the basis of the characteristics of the evolution of these two dielectric *** whole evolution of the transition from the NR state to the ER state is reflected by the temperature-dependent polarization versus electric field(P-E)hysteresis loops,i.e.,from the square loops,via the double-like loops,to the slim *** characteristic temperatures,including TP-N,TN-R and TR-dis,are determined by the characteristics of the evolution of P-E ***,a phase diagram of NBT-xST was constructed according to these characteristic *** importantly,the relationship between polarization responses and heterogeneous polar phase coexistence has been established and a schematic diagram is *** work will help to understand the phase evolution and its impact on the macroscopic properties of NBT and the associated NBT-based solid solutions.

关键词： Phase diagram Bismuth sodium titanate Relaxor ferroelectric Phase evolution Strontium titanate

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Noncoding RNAs and pancreatic cancer

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World Journal of Gastroenterology 2016年第2期22卷 801-814页

作者： juan-fei peng yan-yan zhuang feng-ting huang shi-neng zhang Department of Gastroenterology Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhou 510120Guangdong ProvinceChina

Noncoding RNAs(nc RNAs) represent a class of RNA molecules that typically do not code for proteins. Emerging data suggest that nc RNAs play an important role in several physiological and pathological conditions such as cancer. The best-characterized nc RNAs are the micro RNAs(mi RNAs), which are short, approximately 22-nucleotide sequences of RNA of approximately 22-nucleotide in length that regulate gene expression at the posttranscriptional level, through transcript degradation or translational repression. Mi RNAs can function as master gene regulators, impacting a variety of cellular pathways important to normal cellular functions as well as cancer development and progression. In addition to mi RNAs, long nc RNAs, which are transcripts longer than 200 nucleotides, have recently emerged as novel drivers of tumorigenesis. However, the molecular mechanisms of their regulation and function, and the significance of other nc RNAs such as piwi-interacting RNAs in pancreas carcinogenesis are largely unknown. This review summarizes the growing body of evidence supporting the vital roles of nc RNAs in pancreatic cancer, focusing on their dysregulation through both genetic and epigenetic mechanisms, and highlighting the promise of nc RNAs in diagnostic and therapeutic applications of pancreatic cancer.

关键词： Noncoding RNAs Diagnosis Pancreaticcancer Therapy Prognosis

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WATuning:A Workload-Aware Tuning System with Attention-Based Deep Reinforcement Learning

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Journal of Computer Science & Technology 2021年第4期36卷 741-761页

作者： Jia-Ke Ge yan-Feng Chai Yun-Peng Chai Key Laboratory of Data Engineering and Knowledge Engineering of Ministry of Education Renmin University of China Beijing 100872China School of Information Renmin University of ChinaBeijing 100872China College of Computer Science and Technology Taiyuan University of Science and TechnologyTaiyuan 030027China

Configuration tuning is essential to optimize the performance of systems(e.g.,databases,key-value stores).High performance usually indicates high throughput and low *** present,most of the tuning tasks of systems are performed artificially(e.g.,by database administrators),but it is hard for them to achieve high performance through tuning in various types of systems and in various *** recent years,there have been some studies on tuning traditional database systems,but all these methods have some *** this article,we put forward a tuning system based on attention-based deep reinforcement learning named WATuning,which can adapt to the changes of workload characteristics and optimize the system performance efficiently and ***,we design the core algorithm named ATT-Tune for WATuning to achieve the tuning task of *** algorithm uses workload characteristics to generate a weight matrix and acts on the internal metrics of systems,and then ATT-Tune uses the internal metrics with weight values assigned to select the appropriate ***,WATuning can generate multiple instance models according to the change of the workload so that it can complete targeted recommendation services for different types of ***,WATuning can also dynamically fine-tune itself according to the constantly changing workload in practical applications so that it can better fit to the actual environment to make *** experimental results show that the throughput and the latency of WATuning are improved by 52.6%and decreased by 31%,respectively,compared with the throughput and the latency of CDBTune which is an existing optimal tuning method.

关键词： attention mechanism auto-tuning system reinforcement learning(RL) workload-aware

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涡流钻头降压机制及设计原则

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中国石油大学学报（自然科学版） 2014年第1期38卷 64-69页

作者：朱海燕邓金根王墨翟薛亮闫传梁中国石油大学油气资源与探测国家重点实验室北京102249 西南石油大学油气藏地质及开发工程国家重点实验室四川成都610500 中国石油大学石油工程学院北京102249

涡流钻头通过反向喷嘴和高速旋转形成负压漩涡,降低井底压差,提高钻井的机械钻速.对涡流钻头降压机制进行研究.采用混合网格计算方法分析反向喷嘴的轴向倾角、径向倾角、上返流量、出口高度和旋转速度等对涡流钻头降压性能的影响,并提... 详细信息

涡流钻头通过反向喷嘴和高速旋转形成负压漩涡,降低井底压差,提高钻井的机械钻速.对涡流钻头降压机制进行研究.采用混合网格计算方法分析反向喷嘴的轴向倾角、径向倾角、上返流量、出口高度和旋转速度等对涡流钻头降压性能的影响,并提出涡流钻头的设计原则.结果表明：反向喷嘴下方井底钻井液回流是影响涡流钻头降压能力的主要因素.涡轮钻头设计的理论原则：轴向倾角为150°～ 180°、径向倾角为60°～75°、上返流量大于30％、反向喷嘴的出口高度为100～140 mm,井壁间隙应小于3 mm,尽可能地提高钻头旋转速度.

关键词：钻井涡流钻头井底压差反向喷嘴数值模拟

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The pentatricopeptide repeat protein EMP601 functions in maize seed development by affecting RNA editing of mitochondrial transcript ccmC

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The Crop Journal 2023年第5期11卷 1368-1379页

作者： Rongrong Chen Qianhan Wei yan Liu Jiankun Li Xuemei Du yan Chen Jianhua Wang Yunjun Liu The National Forestry and Grassland Administration Engineering Research Center for Germplasm Innovation and Utilization of Warm-Season Turfgrasses Jiangsu Key Laboratory for the Research and Utilization of Plant ResourcesInstitute of BotanyJiangsu Province and Chinese Academy of Sciences(Nanjing Botanical Garden Mem.Sun Yat-Sen)Nanjing 210008JiangsuChina Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081China College of Agronomy and Biotechnology China Agricultural UniversityBeijing 100094China College of Agronomy Henan Agricultural UniversityZhengzhou 450002HenanChina

Although several pentatricopeptide repeat(PPR) proteins are involved in post-transcriptional processing of mitochondrial RNA, it is unclear which specific protein is involved in the RNA editing of ccmC in maize(Zea mays). Here we report the identification of the maize empty pericarp 601(emp601) mutant and the map-based cloning of the Emp601 gene, which encodes an E2-type PPR protein that is targeted to mitochondria. A single-nucleotide deletion in the emp601 mutant caused a frameshift and introduced a premature stop codon into the predicted EMP601. This mutation was associated with reduced accumulation of mitochondrial complex Ⅲ as well as with inhibition of growth and differentiation of basal endosperm transfer layer cells, leading to final degeneration of the embryo and endosperm. We determine that loss of EMP601 function prevents the C-to-U RNA editing of the mitochondrial transcript ccmC at position ***601 binds to the ccmC transcript and directly interacts with Multiple organellar RNA editing factor 8and may be a component of the plant mitochondrial editosome. We conclude that EMP601 functions in RNA editing of mitochondrial ccmC transcripts and influences mitochondrial function and seed development.

关键词： Maize Empty pericarp 601 PPR Mitochondrial Ccmc Seed development

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Geomagnetic observation in both on-ground and under-ground environments with SQUID

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Journal of Earth Science 2024年

作者： Longqing Qiu Jiaxi yan Chengliang Xie Jian Zhang Guofeng Zhang Jun Wu Yifeng pei Shumin Yu Jiawei Luo Liangliang Rong Yun Wang Xiaoming Xie National Key Laboratory of Materials for Integrated Circuits， Shanghai Institute of Microsystem and Information Technology， Chinese Academy of Sciences (CAS) CAS Center for Excellence in Superconducting Electronics (CENSE) University of Chinese Academy of Sciences School of Geophysics and Information Technology， China University of Geosciences

Long-term， high-precision geomagnetic observations hold significant scientific and practical importance in fundamental geosciences studies and navigation applications. In this study， we utilized an LTS-SQUID （Low-Temperature-Superconduncor Superconducting QUantum Interference Device） and a fluxgate magnetometer to conduct geomagnetic observations both at the surface and in deep underground tunnels （848 meters below sea level） at the Huainan underground laboratory （HNLab）. In the underground tunnels， the geomagnetic background exhibited exceptional stability without diurnal variations， especially at frequencies greater than 1 Hz. This stability enhances the ability to distinguish weak variations in the geomagnetic field. The geomagnetic survey and comparative analysis show that the deep underground laboratory offers an advantageous environment for long-term， high-precision geomagnetic observations at the fT (fT: femtotelsla， 1 fT = 10-15T) level， since it is characterized as a very low magnetic and vibrating noise background. With respect to the high-precision LTS-SQUID sensors， we focused discussions on the frequency band of 1 Hz to 50 kHz， including Schumann resonances. Theoretically， the SQUID system has a system noise of 3 fT/√Hz， enabling the capture of subtle Schumann Resonances both underground and on the surface. However， it is difficult to definitively determine the peaks at 2-10 Hz as the fundamental modes of Schumann resonance similar as the one observed at the surface. This uncertainty may be attributed to the microtremors originating from background vibrations， such as ventilation， or the attenuation of Schumann resonances beyond the sensitivity range of the SQUID due to the thicker overlying sedimentary layer.

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一种局部地面定位系统的研究与探索

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科学技术与工程 2017年第10期17卷 251-257页

作者：严新辉傅菊根安徽理工大学土木建筑学院淮南232001

针对传统定位技术定位精度低、稳定性较差,无法在室内环境定位以及定位对象局限于数字设备的缺点,提出一种依靠物体对地面产生压力进行定位的方法。该方法通过在地面下铺设经过改进的矩阵扫描电路,实时获得地面所有物体踩压位置数据,将... 详细信息

针对传统定位技术定位精度低、稳定性较差,无法在室内环境定位以及定位对象局限于数字设备的缺点,提出一种依靠物体对地面产生压力进行定位的方法。该方法通过在地面下铺设经过改进的矩阵扫描电路,实时获得地面所有物体踩压位置数据,将该数据通过互联网发送至用户智能终端实现定位。首先介绍了定位系统的原理,接着介绍局部地面定位系统中的一些参数,然后对智能终端程序进行流程分析并进行数据仿真,模拟了人在地面向各个方向行走时地面数据的变化并总结了其规律;最后,制作了相关硬件并根据仿真得出的算法进行了手机端软件的编写,完成了整个系统的开发,实现了局部地面定位系统在定位导航、安防监控、信息输入方面的功能。

关键词：定位技术扫描电路智能终端地面定位

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Magnetic skyrmions in curved geometries

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Rare Metals 2022年第7期41卷 2184-2199页

作者： yan Liu Na Cai Ming-Zhu Xin Shuang Wang College of Sciences Northeastern UniversityShenyang 110819China

In curved geometries,a lot of novel curvaturedriven effects are discovered due to the curvature-induced effective anisotropy and Dzyaloshinskii-Moriya *** effect also provides means to modify conventional results and launch new functionalities in study of magnetic *** skyrmions are particle-like spin textures with topological *** has been found in several magnetic materials and has been one of the research hotspots in magnetism and spintronics as the carriers of ***-Moriya interaction and anisotropy have significant effects on the formation and stability of magnetic *** magnetic skyrmions in curved geometries show some novel characteristics,and the study in this field may promote the development of magnetic *** article provides a review of the present state of the research on skyrmions in curved geometries including curved nanotracks,thin films with curved defect,nanotubes,spherical and hemispherical *** reviewmainly covers three aspects,the formation and stability of skyrmions,the shape and size of skyrmions,and the dynamical behaviors of skyrmions in curved geometries.

关键词： Magnetic skyrmions Curved geometries Nanotubes Nanospheres

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