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On design of physical random access channel in high-speed railway LTE systems

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Chinese Science Bulletin 2014年第35期59卷 5042-5050页

作者： Gang Wu hang yuan wei Guo Su Hu Shaoqian Li National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of China

For the uplink in the long-term evolution(LTE)systems,the physical random access channel(PRACH)adopts Zadoff–Chu(ZC) sequences as preamble sequences,and each user can choose a unique cyclic shift for user *** high-mobility scenario,the Doppler frequency shift raises up the false alarm probability by inducing the correlation peak offsetting at the receiver *** detection method utilizes multiple search windows for searching the potential uplink *** the Doppler frequency shift is larger than the subcarrier spacing,the energy of correlation peak leaks outside the search window and increases the false alarm *** this paper,we present a novel design for PRACH preamble sequence for high-speed railway *** numerical observation,we find out that the offset of the correlation peaks only depends on the initial root sequence number and the length of ZC ***,the root number of ZC sequences should be carefully designed to generate a preamble sequence to fight against the Doppler frequency ***,those offsets of the correlation peaks are concentrated within a single search window,resulting in lower complexity of detection and lower probability of false alarm for random access in LTE uplink.

关键词：随机接入信道高速铁路 LTE 设计系统物理多普勒频移频率偏移

Nonlinearity Correction of Fourier Transform Spectrometer in Solar Observation Using Simulated Annealing

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Research in Astronomy and Astrophysics 2023年第5期23卷 172-179页

作者： Ze-Yin Dong Xian-Yong Bai Song Feng yuan-Yong deng Zi-hang Yu Wen-Tong Ao Xiao Yang Zhi-Yong Zhang Zhi-wei Feng Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming 650500China Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 101408China

A Fourier transform spectrometer(FTS)has been used to observe solar activities due to its ultra-high spectral ***,the FTS in-band spectra are usually distorted and some artifacts appear in out-of-band regions due to nonlinear ***,the FTS nonlinear problem must be *** this study,we proposed a novel method to correct the nonlinear effects using simulated *** simulated several nonlinear spectra to evaluate the performance of our *** calculated quadratic coefficients are extremely close to the given values,demonstrating that the method is effective and *** proposed method is further used to correct the blackbody and solar spectra with nonlinearity obtained by Bruker IFS-125HR installed at the Huairou Solar Observing Station,which is a pathfinder for the accurate infrared magnetic field measurements of the Sun *** the blackbody spectra,the nonlinearity in low-and high-frequency regions are corrected by 89.09%and 60.84%.The nonlinear correction of the solar spectra in the low-and high-frequency regions have reached 65.34%and 81.04%,*** results prove that our method can correct the nonlinear problem to improve the data accuracy.

关键词： Sun infrared-instrumentation interferometers-techniques interferometric

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抛物型方程移动界面的并行差分格式

工程数学学报 2004年第F12期21卷 121-126页

作者：袁光伟杭旭登北京应用物理与计算数学研究所应用科学计算部计算物理实验室北京8009信箱北京100088

本文构造了抛物型方程的带移动界面的一般并行差分格式,并证明了其稳定性。许多简单实用的差分格式都能从中导出。理论分析和数值试验检验了算法的稳定性,精度和并行性。

关键词：抛物型方程差分格式证明并行性界面数值试验稳定性移动算法精度

Lanthanide-containing persistent luminescence materials with superbright red afterglow and excellent solution processability

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Science China Chemistry 2021年第12期64卷 2125-2133页

作者： Ming xu Jia Liu Xianlong Su Qianwen Zhou hang yuan Yue Wen Yihang Cheng Fuyou Li Department of Chemistry&State Key Laboratory of Molecular Engineering of Polymers Fudan UniversityShanghai200433China Shanghai Taywell Biotechnology Co. Ltd.Shanghai200438China

Lanthanide-containing persistent luminescence materials are promising candidates for a wide range of applications by virtue of splendid superiorities in afterglow ***,it is a crucial challenge to achieve high-quality afterglow materials at the attractive nanoscale,with uniform size,controllable morphology,and satisfying ***,a bottom-up approach was developed to construct the high-quality afterglow nanoparticles,incorporating luminescent lanthanide complex and organic molecular ingredients under mild *** nanoparticles exhibited intrinsic lanthanide luminescence with superbright red afterglow(>10 cd m^(−2))in a homogeneous *** afterglow solution with excellent processability can serve as ideal building blocks for the on-demand fabrication of functional ***-dispersible afterglow nanoparticles with state-of-the-art high brightness were uniformly constructed to perform whole-blood lateral flow assay of procalcitonin with a naked-eye detection limit of 0.5 ng mL^(−1),promoting the point-of-care testing development.

关键词： persistent luminescence lanthanide photochemical afterglow solution processing point-of-care testing

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Effects of solid-solution temperature on microstructure and mechanical properties of a novel 2000MPa grade ultra-high-strength steel

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Journal of Iron and Steel Research International 2020年第6期27卷 710-718页

作者： Chun-xu Wang yuan-hang Gao Yong Li Shun Han Shao-zun Liu Peng-jie Zhang Central Iron and Steel Research Institute Beijing100081China

A novel 2000 MPa grade ultra-high-strength steel AIR0509 with high fracture toughness and low cost has recently been developed. The effects of solid-solution temperature on the microstructure and mechanical properties of this steel were inves-tigated. The increase in solid-solution temperature first increased and then decreased the values of ultimate strength (UTS) and Charpy U-notch (CUN) energy. The increase in the UTS and CUN values was caused by the dissolution of the primary carbides M6C and MC, while the decrease in both strength and toughness was due to the increase in the prior austenite grain size. Samples that were solid-solution treated at 1000℃ exhibited an optimal combination of strength and toughness with a UTS of 2020MPa, yield strength of 1780MPa, and CUN energy of 68J, as well as a correlative fracture toughness KIC value of about 105MPam1/2.

关键词： Ultra-high-strength steel Solid-solution treatment Carbide Mechanical property Microstructure

Small intestine angioleiomyoma as a rare cause of perforation:A case report

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World Journal of Clinical Cases 2024年第12期12卷 2116-2121页

作者： Teng-yuan Hou wei-Juo Tzeng Pei-hang Lee Department of General Surgery Kaohsiung Chang Gung Memorial HospitalKaohsiung 833Taiwan Department of Anatomical Pathology Kaohsiung Chang Gung Memorial HospitalKaohsiung 833Taiwan

BACKGROUND Angioleiomyoma is a rare and benign stromal tumor typically found in subcutaneous *** rarely occurs in the gastrointestinal *** the reported cases,the most common complication was gastrointestinal *** has only been reported as a complication in the last few *** SUMMARY This case report detailed the discovery of intestinal angioleiomyoma in a 47-yearold male presenting with abdominal pain that had persisted for 3 *** suspecting hollow organ perforation,surgical intervention involving intestinal resection and anastomosis was *** The report underscores the significance of early surgical intervention in effectively treating angioleiomyoma while emphasizing the pivotal role of timely and appropriate measures for favorable outcomes.

关键词： Angioleiomyoma Intestinal perforation Abdomen Acute Diarrhea Case report

Genome-wide analysis of Panonychus citrimicro RNAs witha focus on potential insecticidal activity of 4 micro RNAs toeggs and nymphs

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Insect Science 2024年第2期31卷 354-370页

作者： Chuan-Zhen Li Yu-hang Liu deng Pan Meng-Hao Xia Qiang Zhang Yu-Chuang Li Guo-Rui yuan Jin-Jun Wang wei Dou Key Laboratory of Entomology and Pest Control Engineering College of Plant ProtectionAcademy of Agricultural SciencesSouthwestUniversityChongqingChina Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River(Ministry of Education) Academy of Agricultural SciencesSouthwest UniversityChongqingChina

Panonychus citriMcGregor(Acari:Tetranychidae),a destructive citrus pest,causes considerable annual economic losses due to its short lifespan and rapid ***(miRNA)-induced RNA interference is a promising approachfor pest control because of endogenous regulation of pest growth and *** for miRNAs with potential insecticidal activity ***,genome-wide analysis ofmiRNAs at different developmental stages was conducted,resulting in the identificationof 136 miRNAs,including 73 known and 63 novel miRNAs.A total of 17 isomiRNAsand 12 duplicated miRNAs were ***-1 and miR-252-5p were identified asreference miRNAs *** *** on differential expressionanalysis,treatments with miR-let-7a and miR-315 mimics and the miR-let-7a antagomirsignificantly reduced the egg hatch rate and resulted in abnormal egg ***-expression or downregulation of miR-34-5p and miR-305-5p through feeding significantlydecreased the adult eclosion rate and caused molting *** 4 miRNAs,miR-let-7a,miR-315,miR-34-5p,and miR-305-5p,had important regulatory functions and insectici-dal properties in egg hatching and adult *** general,these data advance our un-derstanding of miRNAs in mite biology,which can assist future studies on insect-specificmiRNA-based green pest control technology.

关键词： growth and development microRNAs Panonychus citri referencemiRNAs regulation small RNA libraries

The expression,function,and coding potential of circular RNA circEDC3 in chicken skeletal muscle development

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Journal of Integrative Agriculture 2022年第5期21卷 1444-1456页

作者： wei yuan-hang ZHAO Xi-yu SHEN Xiao-xu YE Lin Zhang Yao WANG Yan LI Di-yan ZHU Qing YIN Hua-dong Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province Sichuan Agricultural UniversityChengdu 611130P.R.China

As an emerging class of non-coding transcripts,circular RNAs(circRNAs)are proved to participate in the complex process of myogenesis in diverse species.A previous study has identified circular RNA EDC3(circEDC3)as a typical covalently closed circular RNA abundant in chicken skeletal *** study found that circEDC3 is a conservative circular RNA and performed functional analysis to investigate the role of circEDC3 in chicken muscle *** results indicated that circEDC3 could inhibit(P<0.05)chicken skeletal muscle satellite cells(SMSCs)proliferation and differentiation but had no significant influence on SMSCs ***,bioinformatics analysis showed that circEDC3 had promising coding *** open reading frames(ORF)were found in circEDC3 in this ***,this study predicted that circEDC3 had internal ribosome entry sites(IRES)and N6-methyladenosine(m6A)motifs in different species,implying that circEDC3 might be *** study revealed that circEDC3 might be a negative regulator in chicken muscle development and suggested it has protein-coding potential in different species.

关键词： circEDC3 chicken SMSCs myogenesis coding potential

A Robust Self-healing Polyurethane Elastomer Enabled by Tuning the Molecular Mobility and Phase Morphology through Disulfide Bonds

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Chinese Journal of Polymer Science 2021年第10期39卷 1299-1309,I0007页

作者： Hai-Tao Wu Bi-Qiang Jin Hao Wang Wen-Qiang Wu Zhen-Xing Cao Zhao-Yang yuan Yue Huang wei-hang Li guang-Su Huang Lu-Sheng Liao Jin-Rong Wu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineerngSichuan UniversityChengdu 610065China guangdong Provincial Key Laboratory of Natural Rubber Processing Agricultural Products Processing Research Institute of Chinese Academy of Tropical Agricultural SciencesZhanjiang 524001China

Elastomers with outstanding strength,toughness and healing efficiency are highly promising for many emerging ***,it is still a challenge to integrate all these beneficial features in one ***,an asymmetric alicyclic structure adjacent to aromatic disulfide was tactfully introduced into the backbone of polyurethane(PU)***,such elastomer(PU-HPS)was fabricated by polycondensing polytetramethylene ether glycol(PTMEG),isophorone diisocyanate(IPDI)and p-hydroxydiphenyl disulfide(HPS)via one-pot *** molecular mobility and phase morphology of PU-HPS can be tuned by adjusting the HPS ***,the dynamic exchange of hydrogen and disulfide bonds in the hard segment domains can also be *** optimized sample manifests outstanding tensile strength(46.4 MPa),high toughness(109.1 MJ/m^(3)),high self-healing efficiency after fracture(90.3%),complete scratch recovery(100%)and good puncture ***,this work provides a facile strategy for developing robust self-healing polymers.

关键词： Self-healing Polyurethane Disulfide bonds Chain mobility Phase morphology