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电压暂降过程中的双馈风力发电机无功功率调节能力(英文)

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电力科学与技术学报 2008年第3期23卷 25-33,95页

作者： N. Aparicio z. Chen h. Beltran E. Belenguer 海梅一世大学工业系统工程与设计系西班牙卡斯特利翁Castelló 12071 奥尔堡大学能源技术研究所丹麦奥尔堡Aalborg 9200

西班牙风力发电容量日益增加,已迫使输电系统运营机构(TSO)对电压骤降期间风力发电机无功出力提出新的要求.在稳态运行条件下,双馈风力发电机方便调节无功功率;但在电压暂降过程中,难于提供足够的无功功率.论文仿真分析了双馈风力发电... 详细信息

西班牙风力发电容量日益增加,已迫使输电系统运营机构(TSO)对电压骤降期间风力发电机无功出力提出新的要求.在稳态运行条件下,双馈风力发电机方便调节无功功率;但在电压暂降过程中,难于提供足够的无功功率.论文仿真分析了双馈风力发电机的无功出力,考虑保护系统和电网侧换流器共同作用,以满足无功平衡要求;故障瞬间,Crowbar电阻及其连接时间对无功平衡影响大,而电网侧换流器充当STATCOM作用,有助于改善电压波形,以实现转子侧换流器的重接.

关键词：电网要求无功消耗可再生能源系统电压暂降风能

Some Anzahl Theorems in Symmetric Matrices over Finite Local Rings (Ⅰ)

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Journal of Mathematical Research and Exposition 2006年第3期26卷 423-439页

作者：刘岩南基洙北京交通大学数学系北京100044 大连理工大学应用数学系辽宁大连116024

Let An（R） be the set of symmetric matrices over z/p^kz with order n, where n 〉 2, p is a prime, p 〉 2 and p≡1（mod4）, k 〉 1. By determining the normal form of n by n symmetric matrices over z/p^kz, we compute the number of the orbits of An（R） and then compute the order of the orthogonal group determined by the special symmetric matrix. Finally we get the number of the symmetric matrices which are in the same orbit with the special symmetric matrix.

关键词： congruent transformation normal form of symmetric matrix orthogonal group.

Key progresses of MOE key laboratory of macromolecular synthesis and functionalization in 2022

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Chinese Chemical Letters 2024年第3期35卷 114-126页

作者： Xumeng Deng Kaihao Chen Kai Pang Xiaoting Liu Minsong Gao jie Ren Guanwen Yang Guangpeng Wu Chengjian zhang Xufeng Ni Peng zhang jian ji jianzhao Liu zhengwei Mao ziliang Wu zhen Xu haoke zhang hanying Li MOE Key Laboratory of Macromolecular Synthesis and Functionalization International Research Center for X PolymersDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

In 2022,The MOE Key Laboratory of Macromolecular Synthesis and Functionalization in zhejiang University had achieved several important ***,a series of well-defined dinuclear organoboron catalysts were developed to precisely control the enchainment of ether and carbonate segments during the copolymerization of CO_(2)and ***,polyester had been synthesized through cationic copolymerization of cyclic ***,ring-opening polymerization of carbon dioxide based valerolactone had been achieved,revealing the prospect of 3-ethylidene-6-vinyltetrahydro-2h-pyran-2-one(EVL)in utilizing CO_(2)and synthesizing functional ***,machine learning methods have been applied to biomaterial research,enabling high-throughput screening of functional biomaterial surfaces for implantable devices,and searching for potent antimicrobial peptides in whole combinatorial peptide ***,methods of characterization of biomacromolecule RNA transcription and manipulation of nucleoside modification were ***,artificial enzymes-armed Bifidobacterium Longum probiotics were established to tune down gut ***,three-dimensional(3D)printing technologies were used to engineer tough supramolecular ***,hydroplastic foaming graphene frameworks for acoustic and conductive polymer composites were provided for ***,aggregate photophysics about the nature of through-space interactions(TSIs)and manipulating their strength in small molecules with non-conjugated structure had been ***,the forming mechanism of a newfound nested texture in poly(L-lactic acid)(PLLA)spherulitic films had been ***,the isotropically dyeing mechanism of KDP single crystals grown from hydrogels have been *** related works are reviewed in this paper.

关键词： Polymer Catalyst Biomaterial research mRNA hydrogel Graphene Crystal

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论高罗佩《琴道》的古琴音乐姿态艺术观

湘潭大学学报（哲学社会科学版） 2021年第6期45卷 180-187页

作者：唐璟季水河湘潭大学文学与新闻学院湖南湘潭411105

高罗佩《琴道》中的音乐姿态艺术观,主要由古琴音乐姿态的文化涵化与融合、音乐姿态身份与价值主体间性、表现姿态话语体系三个部分构成。从古琴制式、身体、叙事姿态三个维度阐释了制式姿态中的“自然”意义、表演姿态中的共鸣效果、... 详细信息

高罗佩《琴道》中的音乐姿态艺术观,主要由古琴音乐姿态的文化涵化与融合、音乐姿态身份与价值主体间性、表现姿态话语体系三个部分构成。从古琴制式、身体、叙事姿态三个维度阐释了制式姿态中的“自然”意义、表演姿态中的共鸣效果、聆听姿态中的交流价值。其音乐姿态艺术观体现了技与艺的统一、器与道的融合、天与人的合一等重要特点,为中国音乐审美理想和东西方音乐艺术対话提供了重要启示。

关键词：高罗佩琴道音乐姿态艺术观

PdO^(0,±1),Pdh^(0,±1)及PdOh分子结构和电子性质的从头计算

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物理化学学报 2010年第2期26卷 436-440页

作者：孙希媛杜际广蒋刚四川大学原子与分子物理研究所成都610065

利用多种从头计算方法对PdO0,±1,Pdh0,±1以及PdOh的结构和电子性质进行了理论研究.优化了PdO分子两个能量相近的态(3Π和3Σ-),结果表明PdO的3Π态较3Σ-态更为稳定,在单双激发耦合簇理论(CCSD)水平下3Σ-态的总能量比3Π态的高出0.28... 详细信息

利用多种从头计算方法对PdO0,±1,Pdh0,±1以及PdOh的结构和电子性质进行了理论研究.优化了PdO分子两个能量相近的态(3Π和3Σ-),结果表明PdO的3Π态较3Σ-态更为稳定,在单双激发耦合簇理论(CCSD)水平下3Σ-态的总能量比3Π态的高出0.286eV.在结构优化的基础上计算了PdO以及Pdh的绝热电离能(AIE)和电子亲和能(AEA),计算结果与实验值符合得很好.PdOh的基态为Cs对称性的角型结构Pd—Oh(2A′态),另外还优化得到两个2A″态的亚稳结构,分别对应于Pd—Oh和O—Pd—h,CCSD水平下两个亚稳态的总能量较基态分别高0.405和2.284eV,优化得到了连接这两个2A″态的过渡态,并计算了相应的反应能垒.

关键词：从头计算过渡态电子性质分子轨道能垒内禀反应坐标计算

Strong Correlation of Abnormal Serum and Urinary Iodine Levels with Papillary Thyroid Cancer:A Case-control Study

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Biomedical and Environmental Sciences 2020年第1期33卷 62-67页

作者： XIU Cheng hE Qian zhAO hong jian YUAN zhen Nan GUO Lun hua WANG Feng Qian YANG Xian Guang TIAN Qiu Shi SUN Qi hao MIAO Su Sheng SUN ji FAN Li Jun jiA Shen Shan Department of head and Neck Oncology the Third Affiliated HospitalHarbin Medical UniversityHarbin 150030HeilongjiangChina Public health College Shandong First Medical University&Shandong Academy of Medical SciencesTai’an 271016ShandongChina General Surgery Department People's Hospital of Chengwu CountyHeze 274200ShandongChina Public health College Harbin Medical UniversityHarbin 150076HeilongjiangChina Center for Endemic Disease Control Chinese Center for Disease Control and PreventionHarbin Medical UniversityHarbin 150076HeilongjiangChina

Thyroid cancer is the most common malignancy of the endocrine system,and its incidence is increasing *** China,its incidence has increased from 1.78/104 in 1988 to 10.58/104 *** cancers are mainly classified into papi... 详细信息

关键词： PTC Strong Correlation Abnormal Serum and Urinary Iodine Levels Papillary Thyroid Cancer:A Case-control Study

Influence of Pyrocarbon Matrix Concentration on Thermal Physical and Mechanical Properties of Pitch-based Carbon/carbon Composites

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Journal of the Chinese Ceramic Society 2016年第4期3卷 167-176页

作者： LI Yan CUI hong jiE Yujie ji A'lin zhOU Shaojian zhENG Rui School of Materials Science Northwestern Polytechnic University Xi'an Aerospace Composites Research Institute

The effect of pyrocarbon(PyC) concentration on the thermal physical and mechanical properties of quasi 3dimensional carbon fiber fabrics reinforced pitch-based carbon matrix composites was *** the PyC concen-tration increased from 0 to 22.9vol.%,the tensile strength of pitch-based C/C(Carbon/Carbon) composites initially in-creased and then decreased,so was the tensile *** coefficients of thermal expansion(CTE) were in the sequence of 10.2vol.%z *** the same temperature conditions,PyC layer had a positive-going influence on the TC of the C/C composite,the composite with 22.9vol.%PyC concentrations possessed the highest TC *** thermal shock resistance of the material with 10.2vol.%PyC concentrations showed the highest *** is logical to conclude that by adding the a suitable PyC concentration into the carbon fabrics,thermo- mechanical properties,the major concerns for the safety design of load-bearing structural parts,can be tailored,which increase the reliability of pitch-based C/C composites as a structure unit.

关键词： carbon/carbon composite interfacial carbon layer thermo-mechanical properties thermal shock resistance

高平重楼——越南北部重楼属(延龄草科)一新种(英文)

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植物分类学报 2006年第6期44卷 700-703页

作者：纪运恒李恒周浙昆中国科学院昆明植物研究所昆明650204

描述了越南北部高平省延龄草科Trilliaceae重楼属Paris一新种——高平重楼P. caobangensis Y. h. ji, h. Li & z. K. zhou。该新种形态与缅甸重楼P. birmanica (Takht.) h. Li & Noltie和南重楼P. vietnamensis (Takht.) h. Li相似,因地上茎高仅30–35 cm,叶片卵状披针形,约9.5×4.5 cm,基出侧脉一对,雄蕊数目为花瓣数目的2倍而区别于后二者。

关键词：重楼属高平重楼延龄草科新种高平越南

Geometric Characterizations of Convergence for Sequences of Continuous Linear Functionals

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Journal of Mathematical Research and Exposition 2001年第3期21卷 371-376页

作者：徐际宏安徽师范大学数学系安徽芜湖241000

We prove the following main result: Let X be a normed linear space,fn ∈ X*\{θ},hn = {x ∈ X: fn(x) = l},n = 0, 1,2,...Then w* - limfn = f0 iff h0 lim inf hn and θ limsup hn; when X is a reflexive Banach space, l... 详细信息

关键词： norm-(weak-,weak*-) convergence Kuratowski(Mosco-, Wijsman-) con- vergence.