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Bidirectional secondary transmissions with energy harvesting in cognitive wireless sensor networks

Journal of Central South University 2018年第11期25卷 2626-2640页

作者： TANG Kun shi Rong-hua ZHANG Ming-ying shi He-yuan LEI Wen-tai School of Information Science and Engineering Central South UniversityChangsha 410083China China Electronics Standardization Institute Beijing 100007China School of Software Tsinghua UniversityBeijing 100084China

To the existing spectrum sharing schemes in wireless-powered cognitive wireless sensor networks,the protocols are limited to either separate the primary and the secondary transmission or allow the secondary user to transmit signals in a time slot when it forwards the primary *** order to address this limitation,a novel cooperative spectrum sharing scheme is proposed,where the secondary transmission is multiplexed with both the primary transmission and the relay ***,the process of transmission is on a three-phase time-switching relaying *** the first phase,a cognitive sensor node SU1 scavenges energy from the primary *** the second phase,another sensor node SU2 and primary transmitter simultaneously transmit signals to the *** the third phase,the node SU1 can assist the primary transmission to acquire the opportunity of spectrum *** decoding and interference cancellation technique is adopted at the receivers to retrieve the desired *** further derive the closed-form expressions for the outage probabilities of both the primary and secondary ***,we address optimization of energy harvesting duration and power allocation coefficient strategy under performance *** effective algorithm is then presented to solve the optimization *** results demonstrate that with the optimized solutions,the sensor nodes with the proposed cooperative spectrum sharing scheme can utilize the spectrum in a more efficient manner without deteriorating the performance of the primary transmission,as compared with the existing one-directional scheme in the literature.

关键词： cooperative transmission cognitive wireless sensor network time-switching relaying wireless energy harvesting joint optimization

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Development and high-gradient test of a two-half accelerator structure

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Nuclear Science and Techniques 2021年第6期32卷 54-62页

作者： Mao-Mao Peng Jia-Ru shi Hao Zha Xian-Cai Lin Ze-Ning Liu Yu-Liang Jiang Jian Gao Liu-yuan Zhou Fo-Cheng Liu Xiang-Cong Meng Huai-Bi Chen Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging Tsinghua UniversityMinistry of EducationBeijing 100084China

This paper reports on the design,fabrication,RF measurement,and high-power test of a prototype accelerator—such as 11.424 GHz with 12 cells—and a traveling wave of two *** was found that the unloaded gradient reached 103 MV/m during the high-power test and the measured breakdown rate,after 3.17×10^(7) pulses,was 1.62×10^(-4)/pulse/m at 94 MV/m and a 90 ns pulse *** thus concluded that the high-gradient two-half linear accelerator is cost-effective,especially in high-frequency RF linear ***,we suggest that silverbased alloy brazing can further reduce costs.

关键词： Two-half structure Silver-based alloy brazing Low cost High gradient

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Study on the Treatment of Cellulosic Ethanol

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Journal of Environmental Science and Engineering 2010年第1期4卷 20-24页

作者： Zhihui shi Jizu yuan Zonghua Wang Wuhan University of Technology Wuhan 430070 China Nanyang Normal Colloge Nanyang 473000 China

Wastewater from the production of cellulosic ethanol was treated by the processes of internal micro-electrolysis method ＋ABR＋UASB ＋MBR. The results of running indicated that, when COD is 12000 mg/L and HRT of UASB is 48 h, the COD removal rate reaches 72% and HRT of MBR is 20 h, COD removal rate is between 80.8% and 87.5%. The effluent COD concentration stabilized at 301- 537 mg/L, it indicates that the MBR system has a strong ability to resist impact load.

关键词： Cellulosic ethanol micro-electrolysis UASB MBR.

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光学系统离焦对自动调焦评价函数的影响

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光电工程 2005年第12期32卷 51-54,58页

作者：原育凯程仕东裴云天中国科学院上海技术物理研究所

调焦过程可分为调节物距、调节像距和移动镜头三种情况。基于几何光学关系,推导了三种情况下的弥散斑半径和横向放大率与离焦量的关系。利用数字图像处理方法,模拟了这两个因素对自动调焦评价函数的作用,表明弥散斑的扩散在焦前焦后呈... 详细信息

调焦过程可分为调节物距、调节像距和移动镜头三种情况。基于几何光学关系,推导了三种情况下的弥散斑半径和横向放大率与离焦量的关系。利用数字图像处理方法,模拟了这两个因素对自动调焦评价函数的作用,表明弥散斑的扩散在焦前焦后呈现对称影响,而横向放大率的影响则沿光轴单调下降,二者叠加,造成峰值两侧的不对称。当光学系统F数增大时,调焦评价函数变得平缓,从而使横向放大率的影响变得显著,最佳像面因此向焦前偏移。利用CCD成像的实验证明了上述观点。

关键词：自动调焦弥散圆半径横向放大率焦面偏移

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Nickel (Ⅱ) Complex Catalyzed Conjugate Addition Reaction of Functionalised Organozinc Reagents to α,β -Unsaturated Esters

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Chinese Chemical Letters 1999年第1期10卷 17-18页

作者： Yu Lai HU Jian Hua YU shi Yan YANG yuan Qi YIN Jin Xian WANG(State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics. Chinese Academy of Sciences, Lanzhou 730000)(Department of Chemistry, Northwest Normal U State Key Lab. Oxo Synthesis S. Lanzhou Inst. of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China Department of Chemistry Northwest Normal University Lanzhou 730070 China

Functionalized organozinc reagents can easily under 1, 4-addition reaction withunsaturated esters in the presence of catalytic amount of Ni (acac)_2 and tertiary ammes under verymild conditions to give the products in... 详细信息

关键词： Conjugate addition reaction organozinc reagents α,β-unsaturated esters,nickel complex catalysis

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EXPERIMENTAL STUDY ON ENHANCED HEAT TRANSFER WITH NI-BASED IMPLANTED SPIRAL FINNED TUBES

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Journal of Hydrodynamics 2003年第5期15卷 65-69页

作者： Sun Feng zhong, Huang Xin yuan, Wang Nai hua, shi Yue tao, Ping Ya ming School of Energy and Power Engineering, Shandong University, Jinan 250061, China Sch. of Energy and Power Eng. Shandong Univ. Ji'nan 250061 China

The new type of heat exchanger elements-Ni-based Implanted Spiral FinnedTurbes (NISFT) was studied and tested, which can contribute to increase the efficiency andreliability. The relation of Nu, Eu and Re with different fin pitch, fin height, transverse pitchand longitudinal pitch were gained, which constituted the basic foundation for the engineeringapplication of NISFT.

关键词： enhanced heat transfer heat exchanger finned tube

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Geochemical characteristics and sedimentary environment of the Middle Devonian organic-rich shales in the Northwest of Guizhong Depression, Southwest China

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China Geology 2020年第4期3卷 567-574页

作者： Kun yuan Wen-hui Huang Xin-xin Fang shi-zhen Li Ting Wang Tuo Lin Guo-heng Liu China University of Geosciences(Beijing) Beijing 100083China Oil and Gas Resources Survey China Geological SurveyMinistry of Natural Resources Beijing 100083China Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China

In order to figure out the redox conditions and paleo-sedimentary environment of the Middle Devonian shales in the northwest of Guizhong Depression,the trace element analysis was conducted on the Middle Devonian cores(320.35–938.50 m)of the typical shale gas investigation well(GY-1)at a 1.50 m sampling interval through X-ray fluorescence spectroscopy(XRF)and inductively coupled plasma mass spectrometry(ICP-MS).According to the test result,the average values of V/(V+Ni),V/Cr and Ni/Co in Nabiao formation(Fm.)are larger than 0.67,4.65 and 7.71 respectively,and Nabiao *** rich in biological assemblages such as tabasheer,ammonite,*** evidences indicate the rising sea level rose relatively in the sedimentation period of Nabiao *** a deepwater shelf environment,which was favorable for the preservation of organic *** V/(V+Ni),V/Cr and Ni/Co in Luofu *** Tangting *** 0.38–0.65,0.73–4.10 and 3.70–6.72 respectively,indicating that the sea level dropped relatively in their sedimentation period,during which the water bodies became shallow,and the sedimentary environment was a weak oxidizing shallow water shelf *** addition,the variation of TOC has a high correlation with the enrichment degree of Ba element,indicating the favorable conditions for the enrichment and preservation of organic matters under an oxygen-deficient ***,according to the identification of trace element indexes,the northwest of Guizhong Depression experienced the sedimentary cycle of relative rise to relative fall of sea level from bottom to top in the Middle Devonian sedimentation *** relative sea level rose to the highest in the sedimentation period of Nabiao Fm.,in which the organic-rich shales with stable thickness and high organic content were ***,the Nabiao *** be regarded as the favorable exploration target interval in this area.

关键词： Organic-rich shale Devonian Geochemistry Sedimentary environment Guizhong Depression Geological survey engineering Guizhou Province Southwest China

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Protein O-GlcNAcylation homeostasis regulates facultative heterochromatin to fine-tune sog-Dpp signaling during Drosophila early embryogenesis

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Journal of Genetics and Genomics 2023年第12期50卷 948-959页

作者： Yaowen Zhang Haibin Yu Dandan Wang Xiaoyun Lei Yang Meng Na Zhang Fang Chen Lu Lv Qian Pan Hongtao Qin Zhuohua Zhang Daan M.F.van Aalten kai yuan Center for Medical Genetics School of Life Sciences&Hunan Key Laboratory of Molecular Precision MedicineDepartment of OncologyXiangya HospitalCentral South UniversityChangshaHunan 410008China State Key Laboratory of Chemo/Biosensing and Chemometrics College of BiologyHunan UniversityChangshaHunan 410082China National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangshaHunan 410008China Division of Cell and Developmental Biology School of Life SciencesUniversity of DundeeDundee DD15EHUK Department of Molecular Biology and Genetics University of AarhusAarhus 8000Denmark The Biobank of Xiangya Hospital Central South UniversityChangshaHunan 410008China

Protein O-GlcNAcylation is a monosaccharide post-translational modification maintained by two evolutionarily conserved enzymes, O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA). Mutations in human OGT have recently been associated with neurodevelopmental disorders, although the mechanisms linking O-GlcNAc homeostasis to neurodevelopment are not understood. Here, we investigate the effects of perturbing protein O-GlcNAcylation using transgenic Drosophila lines that overexpress a highly active OGA. We reveal that temporal reduction of protein O-GlcNAcylation in early embryos leads to reduced brain size and olfactory learning in adult Drosophila. Downregulation of O-GlcNAcylation induced by the exogenous OGA activity promotes nuclear foci formation of Polycomb-group protein Polyhomeotic and the accumulation of excess K27 trimethylation of histone H3 (H3K27me3) at the mid-blastula transition. These changes interfere with the zygotic expression of several neurodevelopmental genes, particularly short gastrulation (sog), a component of an evolutionarily conserved sog-Decapentaplegic (Dpp) signaling system required for neuroectoderm specification. Our findings highlight the importance of early embryonic O-GlcNAcylation homeostasis for the fidelity of facultative heterochromatin redeployment and initial cell fate commitment of neuronal lineages, suggesting a possible mechanism underpinning OGT-associated intellectual disability.

关键词： Protein O-GlcNAcylation Drosophila Early embryogenesis Polycomb repressive complex Facultative heterochromatin Neurodevelopment sog

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Asymmetric Reduction of Aromatic Ketones Catalyzed by Using (αs,4s)-2-Dichloromethyl-4,5-Dihydro-α-(4-Nitrophenyl)-4- Oxazolemethanol-Borane Complex

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Wuhan University Journal of Natural Sciences 2002年第1期7卷 113-116页

作者： shi Yu, Hu Quan-yuan, Yang Shao-rong, Hu Xian-ming College of Pharmacy, Wuhan University, Wuhan 430072, Hubei, China College of Pharmacy Wuhan University Wuhan Hubei China

Chiral oxazoborolidine borane complex was prepared from (αs, 4s)-2-dichloromethyl-4, 5-dihydro-α-(4-nitrophenyl)-4-oxazolemethanol with Borane in THF. The borane modified by chiral oxazoborolidine enantioselectively reduced aromatic ketones to second-alcohol with about 95%yield and medium optical yields. In the end of article, results are discussed and reduction mechanism is shown which proves the resulting major isomers fit very well.

关键词： asymmetric reduction prochiral ketones chiral oxazoborolidine borane chloramphenicol oxazoline

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精准医疗与胰腺癌

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世界华人消化杂志 2016年第36期24卷 4752-4758页

作者：朱世凯电子科技大学附属医院.四川省人民医院器官移植中心四川省成都市610072

胰腺癌是现代肿瘤学中最具挑战性的难题之一.由于胰腺癌早期诊断极其困难,且较早可发生远处转移,手术切除率不足20%,预后极差.尽管对胰腺癌的诊疗经历多年的艰苦探索,但其生存率并没有明显的提高.因此,早期诊断和治疗是提高胰腺癌患者... 详细信息

胰腺癌是现代肿瘤学中最具挑战性的难题之一.由于胰腺癌早期诊断极其困难,且较早可发生远处转移,手术切除率不足20%,预后极差.尽管对胰腺癌的诊疗经历多年的艰苦探索,但其生存率并没有明显的提高.因此,早期诊断和治疗是提高胰腺癌患者生存率的关键问题所在.随着基因组学大数据时代的来临和生物技术的迅速发展,最近提出的精准医疗的新理念已经迅速成为全球医学界热议和高度关注的焦点.本文阐述近些年来精准医疗理念在胰腺癌临床运用中的现状以及所面临的机遇和挑战,为进一步提高胰腺癌患者的生存率提供新思路.

关键词：胰腺癌精准医疗基因诊断靶向治疗

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