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Geochemical Characteristics and Petrogenesis of Permian Basaltic Rocks in Keping Area,Western Tarim Basin:A Record of Plume-Lithosphere Interaction 被引量:7
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作者 于峻川 莫宣学 +3 位作者 喻学惠 董国臣 付强 邢凤存 《Journal of Earth Science》 SCIE CAS CSCD 2012年第4期442-454,共13页
ABSTRACT: The two basalt flows in Kupukuziman (库普库兹满) Formation of Keping (柯枰) area are the typical products of Permian magmatism. Based on systematic field investigations, we carried out geochemical studi... ABSTRACT: The two basalt flows in Kupukuziman (库普库兹满) Formation of Keping (柯枰) area are the typical products of Permian magmatism. Based on systematic field investigations, we carried out geochemical studies on representative Keping basalts. The results show that the SiO2 contents in basalts range from 44.69 wt.% to 51.68 wt.%, and the total alkalis range from 4.05 wt.% to 5.5 wt.%, belonging to alkaline basalts. The Ti/Y=468.27-565.35 and TIO2=(2.88-3.82) wt.% compared to those of the high-Ti basalts in Emeishan (峨眉山) large igneous province (LIP) (TIO2=(3.58-5.21) wt.%, Ti/Y〉500, Xiao et al., 2004). The contents of MgO and compatible elements Cr (12.9-18.6 ppm), Ni (13.7-22.7 ppm), and Co (39.6-50.2 ppm) are low, which suggest that the samples have undergone varying grades of fractional crystallization. All the samples have uniform REE and other trace element characteristics, with enriched LREE and LILE relative to HREE and HFS, similar REE patterns without Eu anomaly. The basalts are also show slightly depleted of Ta and Nb. They have higher initial STSr/S6Sr ratios (0.707 211-0.708 300), lower tNd(t) values (-2.47 to -4.14), and a narrow range of (208pb/204pb)t=37.535 2-38.297 7, (207pb/204pb)~=15.435 7-15.517 0, and (206Pb/204pb)t=17.206 5-17.874 7 ratios. The Ce/Y versus Zr/Nb diagram shows that the parent magmas were originated from low-degree partial melting of the garnet-lherzolite. The analysis results based on geochemical studies seem all point to the same conclusion that the Keping basalts have formed as a product of the interaction between the plume-derived melts and the lithosphere.Geochemical Characteristics and Petrogenesis of Permian Basaltic Rocks in Keping Area, Western Tarim Basin 展开更多
关键词 Tarim basin PERMIAN large igneous province mantle plume geochemical characteris-tics.
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Synthesis and Characterization of Heteropolytungstosilicate Complexes with the Lanthanide Elements 被引量:1
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作者 WANG Zhan-wen , WU Nai-jun and WANG Shu-fang (Department of Applied Chemistry. Nanjing Institute of Chemical Technology, Nanjing 210009) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1992年第4期343-347,共5页
Lanthanide heteropoly compounds K15[Ln(HSiW9O34)2]·28H2O(Ln = La, Ce, Nd), denoted as Ln(SiW9)2, were synthesized and characterized by element analysis, TG-DTA, IR, UV, XPS and XRD. The results show that partial ... Lanthanide heteropoly compounds K15[Ln(HSiW9O34)2]·28H2O(Ln = La, Ce, Nd), denoted as Ln(SiW9)2, were synthesized and characterized by element analysis, TG-DTA, IR, UV, XPS and XRD. The results show that partial oxygen in Ln(SiW9)2 was coordinated with Ln3- , where Ln-3 was in the inner side of the heteropoly anions, while the fundamental structure of SiW9 had little change. The result was supported by ion exchange experiment. 展开更多
关键词 Tungstosilicic heteropoly complex Lanthanide elements SYNTHESIS characteri-zation.
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Clinical characteristics of patients readmitted for stroke with double anti-platelet therapy after percutaneous coronary intervention
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作者 WANG Ling RAN Peng +1 位作者 CAI An-ping CHEN Ji-yan 《South China Journal of Cardiology》 CAS 2014年第4期227-230,237,共5页
Background The clinical characteristics of stroke patients treated with double anti-platelet therapy (DAPT) after percutaneous coronary intervention (PCI) is not clear. Methods In total, 2675 patients under- went ... Background The clinical characteristics of stroke patients treated with double anti-platelet therapy (DAPT) after percutaneous coronary intervention (PCI) is not clear. Methods In total, 2675 patients under- went PCI and DAPT in Guangdong General Hospital, and 68 out of them were hospitalized due to suspected stroke, of whom 23 were diagnosed as having stroke. Data of the 23 stroke patients were collected and tradi- tional risk factors associated with stroke were analyzed retrospectively. Results The mean age of these pa- tients was 75.6± 8.7 years, and 20 (87.0%) were males. Notably, 19 patients were complicated with hyper- tension, 7 with diabetes mellitus, 7 with previous history of stroke, none with atrial fibrillation (AF) or patent foramen ovale (PFO). Specifically, 22 patients were diagnosed with ischemic stroke, and 1 patient with hemorrhagic stroke. Conclusion Stroke in patients treated with DAPT after PCI was correlated with ad- vanced age, gender, hypertension, diabetes mellitus, stroke history. Long term electrocardiography (ECG) may be needed for the diagnosis of AF, while trans-esophageal echocardiography (TEE) may be needed for PFO. 展开更多
关键词 percutaneous coronary intervention double anti-platelet therapy STROKE clinical characteris-tics
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A Corpus-based Contrastive Study of Characteristic of Economic Words and Common Words
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作者 WANG Lin-zhuo 《海外英语》 2013年第18期258-260,共3页
Economic English is a significant tool for students. This research intends to analyze the lexical characteristics of eco nomic English on vocabulary size, lexical density, word length, and frequency distribution from ... Economic English is a significant tool for students. This research intends to analyze the lexical characteristics of eco nomic English on vocabulary size, lexical density, word length, and frequency distribution from two sources aspects: BROWN Corpus and another corpus built by author, named CEE. 展开更多
关键词 VOCABULARY of ECONOMIC english LEXICAL characteris
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A Study on the Characteristics of Chinese Pidgin English
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作者 邓世平 《海外英语》 2014年第2X期198-199,共2页
Chinese Pidgin English is a variety of the English language.It is one product of language contact.It is a blend;in vocabulary,pronunciation and grammar,it is simplified and localized.It is one kind of spoken language ... Chinese Pidgin English is a variety of the English language.It is one product of language contact.It is a blend;in vocabulary,pronunciation and grammar,it is simplified and localized.It is one kind of spoken language without formal rules,but it plays an important part in the evolution of language. 展开更多
关键词 CHINESE PIDGIN ENGLISH LANGUAGE CONTACT characteri
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Geochemical characteristics of crude oils from Well Zheng-1 in the Junggar Basin, Xinjiang,China
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作者 李志明 张长江 +4 位作者 秦建中 张渠 范明 刘文斌 张志荣 《Chinese Journal Of Geochemistry》 EI CAS 2007年第2期163-169,共7页
Well Zheng-1 is located in the combined area of the central uplift and the north Tianshan piedmont depression in the Junggar Basin. Two oil-bearing beds are recognized at 4788–4797 m of the Lower Cretaceous Tugulu Fo... Well Zheng-1 is located in the combined area of the central uplift and the north Tianshan piedmont depression in the Junggar Basin. Two oil-bearing beds are recognized at 4788–4797 m of the Lower Cretaceous Tugulu Formation (K1tg) and 4808.5–4812.5 m of the Lower Jurassic Sangonghe Formation (J1s). The geochemical characteristics of family composition, carbon isotopic composition, saturated hydrocarbons, sterane and terpane biomarkers and carotane of two crude oils are described in this paper. The results show that the geochemical characteristics of the two crude oils are basically similar to each other, indicating they were all derived mainly from the high mature, brine, algae-rich lake facies sediments. Oil-source correlation revealed that crude oils of the two beds were derived mainly from the source rocks of Permian and mixed by the oil derived from the source rocks of Jurassic and Triassic. This is consistent with the geological background with several sets of source rocks in the area studied. 展开更多
关键词 新疆 准噶尔盆地 Zheng-1井 原油 地球化学特征
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风机电加热融冰叶片的雷击接闪特性
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作者 王欢 胡琴 +2 位作者 舒立春 蒋兴良 唐芳纯 《电工技术学报》 北大核心 2026年第3期1026-1039,共14页
风机叶片的覆冰和雷击问题突出,电加热融冰技术能较好地解决叶片覆冰问题,但电加热融冰叶片(简称融冰叶片)的雷击接闪问题还有待深入研究。该文根据叶片覆冰防护区域设计了融冰叶片,并遵循相似性理论,在雪峰山国家野外站搭建了缩比风机... 风机叶片的覆冰和雷击问题突出,电加热融冰技术能较好地解决叶片覆冰问题,但电加热融冰叶片(简称融冰叶片)的雷击接闪问题还有待深入研究。该文根据叶片覆冰防护区域设计了融冰叶片,并遵循相似性理论,在雪峰山国家野外站搭建了缩比风机叶片长间隙放电试验平台,研究了融冰叶片的雷击接闪特性,分析了接闪点的雷击概率,并与普通叶片进行对比。结果表明:融冰叶片的雷击接闪具有极性效应,导致在正极性雷击时接闪点及其概率分布更为分散。融冰叶片电热元件的雷击烧蚀损伤风险较为突出,其雷击概率与雷电的位置和极性、叶片状态有关;电热元件的雷击概率在雷电来自迎风面时最大(背风面时为0)、正极性雷击或叶片旋转时明显更高。与普通叶片相比,融冰叶片电热元件的邻域电场会产生畸变和屏蔽引下线电场,导致其接闪器及叶身的雷击概率下降,接闪点转移至电热元件,尤其是其边缘处。该文试验结果明晰了融冰叶片的雷击风险,并可为其防雷设计提供指导。 展开更多
关键词 风机叶片 电加热融冰 雷击放电 接闪特性 雷击概率 失效机制
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面向运行灵活性与安全性提升的氢基多能源微网优化调度模型
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作者 倪谢霆 左连勇 +4 位作者 孙勇 付小标 王盛世 崔世常 李宝聚 《电力自动化设备》 北大核心 2026年第2期49-57,共9页
为了充分提升氢基多能源微网(HMM)的运行灵活性与安全性,提出了考虑氢能设备动态物理特性的HMM优化调度模型。综合考虑电解槽、氢燃料电池、甲烷反应器、储氢装置的电化学与热力学过程机理,建立了计及多能耦合动态调节特性的HMM氢能设... 为了充分提升氢基多能源微网(HMM)的运行灵活性与安全性,提出了考虑氢能设备动态物理特性的HMM优化调度模型。综合考虑电解槽、氢燃料电池、甲烷反应器、储氢装置的电化学与热力学过程机理,建立了计及多能耦合动态调节特性的HMM氢能设备模型,以反映氢能设备多能源联供灵活调节及协调互补运行的能力;对各设备的多工作状态特性进行统一表征,考虑氢能设备的安全运行约束和系统平衡约束,提出了HMM的日前优化运行方法。通过算例仿真验证了所提模型和方法的有效性,结果表明,考虑氢能设备的动态物理特性可提高HMM运行的灵活性与安全性,并减小对能源利用效率的计算偏差。 展开更多
关键词 氢基多能源微网 运行灵活性 运行安全性 物理特性 日前优化调度
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Experimental and Numerical Study of Heat Transfer Characteristicsof Supercritical CO_(2) in Rectangular Channel PCHE
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作者 CHEN Yulin WU Xinwen +1 位作者 SHAO Yingjuan ZHONG Wenqi 《Journal of Thermal Science》 SCIE EI CAS CSCD 2024年第6期2299-2317,共19页
Channel structure has a significant effect on the heat transfer performance of PCHE.In this study,a set of rectangular straight channel PCHEs with different cross-section aspect ratios had been tested on S-CO_(2) heat... Channel structure has a significant effect on the heat transfer performance of PCHE.In this study,a set of rectangular straight channel PCHEs with different cross-section aspect ratios had been tested on S-CO_(2) heat transfer experimental platform,the effect of mass flow rate in both cold and heat sides,as well as the cross-section aspect ratio of the rectangular straight channel,on the heat transfer performance of PCHE was investigated.The results show that the comprehensive heat transfer performance of the rectangular cross-section is better than that of the semicircular cross-section;increasing the aspect ratio can improve the comprehensive heat transfer performance of PCHE,but the strengthening effect diminishes as the aspect ratio increases.Increasing the mass flow rate on both sides not only enhances the pre-cooler's cooling capacity and heat transfer,but also raises the pressure drop.In addition,an improved heat transfer correlation for rectangular cross-section PCHE was proposed,considering the effects of cross-sectional aspect ratio and pseudo-critical temperature is proposed in the range of Re from 3169 to 48474 and Pr from 0.98 to 12.5,the fited results better predict the local Nu and f magnitudes and trends in the pre-cooler under different cooling conditions,outperforming the simulated data and Gnielinski and Blasius correlation. 展开更多
关键词 S-CO_(2) rectangular PCHE pre-cooler performance analysis local flow heat transfer characteris
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River basin water resource compensation characteristics by set pair analysis: the Dongiiang example
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作者 Qiuwen CHEN Jing LI +2 位作者 Ruonan LI Wenda WEI Liming WANG 《Frontiers of Earth Science》 SCIE CAS CSCD 2014年第1期64-69,共6页
Flood and drought coexist in many river basins, thus analyses of water resource compensation characteristics become important, since they are the foundation for rational utilization of floodwaters. In this research, s... Flood and drought coexist in many river basins, thus analyses of water resource compensation characteristics become important, since they are the foundation for rational utilization of floodwaters. In this research, set pair analysis (SPA), a relatively new uncertainty analysis method, is used to study the dry and wet compensation characteristics of water resource para- meters. In addition, fuzzy membership and grey correlation degree are adopted to test the result of set pair analysis. The Dongjiang River is taken as an example and the analyzed parameters include precipitation and mean discharge from different hydrological stations. The results show that there is a high homeotype-encountering chance for precipitation and mean discharge between different stations for both dry and wet conditions; thus the compensation capacity is small. Although the mean discharge is synchronous with the precipitation in the river basin, there exists a certain degree of shift, indicating possible utilization of floodwater on a small scale. The results from SPA are consistent with that from a traditional analysis method, showing that SPA is a promising alternative method for studying river basin water resource compensation characteristics, in particular for exploring potential complements embedded in non- complementary general features. 展开更多
关键词 water resources compensation characteris- tics set pair analysis (SPA) Dongjiang River basin
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Lasing characteristics of curved semiconductor nanowires
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作者 Weisong YANG Yipei WANG +3 位作者 Yaoguang MA Chao MENG Xiaoqin WU Qing YANG 《Frontiers of Optoelectronics》 EI CSCD 2013年第4期448-451,共4页
The characteristics of curved semiconductor nanowire (NW) lasers were investigated. The red-shift in the laser spectra with increasing bending angles can be observed much more clearly than that in the photolumi- nes... The characteristics of curved semiconductor nanowire (NW) lasers were investigated. The red-shift in the laser spectra with increasing bending angles can be observed much more clearly than that in the photolumi- nescence (PL) spectra. Due to oscillation of light in resonant cavity, the bending loss of laser exhibits multiple times amplification of that of PL. Furthermore, an abnormal phenomenon of dominant peak switching is found in curved NWs when increasing the pump power, which has been first discovered and reported. 展开更多
关键词 semiconductor nanowire lasing characteris-tics RED-SHIFT bending loss dominant peaks
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Topography of acoustic response characteristics in the midbrain inferior colliculus of Kunming mouse 被引量:1
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作者 SHENJunxian XUZhimin 《Chinese Science Bulletin》 SCIE EI CAS 2003年第2期161-165,共5页
Topography of acoustic response characteris-tics of the midbrain inferior colliculus (IC) of the Kunming mouse was studied by using extracellular recording tech-niques. The characteristic frequency (CF) range represen... Topography of acoustic response characteris-tics of the midbrain inferior colliculus (IC) of the Kunming mouse was studied by using extracellular recording tech-niques. The characteristic frequency (CF) range represented in the different divisions of the IC differed markedly: 4—15 kHz in the dorsal cortex (DC), 10—70 kHz in the centralnucleus (CN), and 4—35 kHz in the external cortex (EC).The CF in the CN increased from dorsal and lateral to ven-tral and medial, higher CFs represented at its ventromedial part and lower CFs at its dorsal part. The isofrequency con-tours of CFs were incurvate. Minimum thresholds (MT) ofthe auditory neurons in DC and the central part of CN were lower (about 10 dB SPL), but considerably higher in thedorsal and ventral region of EC. Results suggest that each of the divisions in the mouse IC may have different auditory functions. 展开更多
关键词 昆明小白鼠 中脑 四叠体下丘 听觉反应 听神经 阈值
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动力涡轮叶-盘结构模态特性的界面参数规律研究
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作者 张晨 温猛 +3 位作者 吴玉萍 袁巍 梅庆 荆建平 《噪声与振动控制》 北大核心 2025年第3期15-20,共6页
叶片-轮盘耦合结构是动力涡轮机械中的关键结构,分析归纳界面参数对叶-盘耦合系统模态特性的影响规律是进行振动特性准确预测与叶-盘结构设计研制的基础。以动力涡轮为例,建立含有枞树形非连续界面带叶冠的叶片-轮盘耦合结构有限元仿真... 叶片-轮盘耦合结构是动力涡轮机械中的关键结构,分析归纳界面参数对叶-盘耦合系统模态特性的影响规律是进行振动特性准确预测与叶-盘结构设计研制的基础。以动力涡轮为例,建立含有枞树形非连续界面带叶冠的叶片-轮盘耦合结构有限元仿真模型,设定多组不同界面参数与工作状态,分别计算不同工作状况下的叶-盘耦合系统模态特性,分析界面参数对叶-盘耦合系统模态特性的影响,形成含有枞树形非连续界面带叶冠的叶片-轮盘耦合结构模型建模方法,进而研究界面参数对叶-盘耦合系统模态特性的影响规律。研究结果表明,界面参数中接触刚度对叶-盘结构振动特性影响最为显著。研究可为动力轮机叶-盘结构耦合系统的性能预测与改进提供必要的理论支撑与技术指导。 展开更多
关键词 振动与波 叶-盘结构 非连续界面 界面参数 模态特性
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吉林烟区烤烟品种适应性试验筛选
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作者 李玉娥 金江华 +4 位作者 郭伟 刘友杰 张世强 张健麒 金洪石 《辽宁农业科学》 2025年第2期37-41,共5页
为了筛选适应吉林烟区优良烤烟品种,应用于生产提供科学依据。以吉烟9号为对照,选择硃砂烟、特香301、延安1号、云烟301、湘烟3号、中川208、2109、2301和云烟121进行适应性试验,分析了不同烤烟品种农艺性状、经济性状、主要化学成分、... 为了筛选适应吉林烟区优良烤烟品种,应用于生产提供科学依据。以吉烟9号为对照,选择硃砂烟、特香301、延安1号、云烟301、湘烟3号、中川208、2109、2301和云烟121进行适应性试验,分析了不同烤烟品种农艺性状、经济性状、主要化学成分、感官质量和外观质量方面的差异。结果表明:延安1号在吉林烟区表现最好,各项指标优良,具有推广价值。延安1号适合在吉林烟区推广种植,其次湘烟3号、特香301、硃砂烟作为吉林烟区进一步增加试种面积的储备品种。 展开更多
关键词 烤烟 品种 适应性 农艺性状 经济性状 感官质量
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构造地球化学测量方法在老挝Phabon金矿床的应用及深部预测
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作者 牛英杰 王居松 +5 位作者 曹敏 陈向平 孙宏岩 王艳辉 席丹 郭豪坤 《矿产勘查》 2025年第2期294-308,共15页
Phabon金矿是老挝境内首个发现的方解石型金矿,矿体赋存于下二叠统的厚层灰岩中,主要受构造控制。为了寻找矿区深边部隐伏矿体,缓解矿山对后备资源的需求,本文以Ⅴ号矿体为研究主体,采用构造地球化学测量方法对其中19种元素数据进行统... Phabon金矿是老挝境内首个发现的方解石型金矿,矿体赋存于下二叠统的厚层灰岩中,主要受构造控制。为了寻找矿区深边部隐伏矿体,缓解矿山对后备资源的需求,本文以Ⅴ号矿体为研究主体,采用构造地球化学测量方法对其中19种元素数据进行统计分析,通过对比已知区未知区地球化学特征,认为Au的成矿过程与Hg、Ni、As的富集有密切关系,其元素组合有一定的找矿指示意义,矿体首尾部出现前缘晕和尾晕叠加现象,分带序列排列复杂且出现“反分带”现象,预测矿区深部存在隐伏矿体。该方法补充和完善了已有成矿模型,可为深边部隐伏矿的预测提供数据支撑,指导矿山开发。 展开更多
关键词 Phabon金矿床 轴向分带序列 构造地球化学 原生晕特征 隐伏矿预测
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阶梯式修理构型层合板湿热振动特性研究
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作者 卢翔 赵耀斌 单金洋 《机械设计与制造》 北大核心 2025年第4期178-183,189,共7页
通过试验和数值计算,研究了不同温度和含湿量情况下,碳纤维/环氧树脂层合板不同修理构型的振动特性。考虑温湿度场的等效原理,在ABAQUS软件中建立不同修理构型的层合板模型,使用试验验证模型的准确性。使用有限元模型研究不同温湿度下... 通过试验和数值计算,研究了不同温度和含湿量情况下,碳纤维/环氧树脂层合板不同修理构型的振动特性。考虑温湿度场的等效原理,在ABAQUS软件中建立不同修理构型的层合板模型,使用试验验证模型的准确性。使用有限元模型研究不同温湿度下挖补角度、挖补孔径以及附加铺层对胶接修理层合板振动特性的影响。结果表明:在不同温度和含湿量情况下,修理后层合板的固有频率高于完整板,同时更容易受到温度和含湿量的影响,使固有频率大幅降低;层合板的固有频率随着挖补角度的增大而增大,但是当挖补角度达到10°后固有频率下降;挖除孔径越大的修理构型,其固有频率增幅越小,更易受温度和含湿量的影响;增加附加补片可以提高修理构型的固有频率,其中双层交叉铺设的修理构型可以更好的降低固有频率对温湿度的敏感性。 展开更多
关键词 复合材料层合板 阶梯挖补修理 湿热环境 振动特性 模态试验 有限元仿真
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汉语他称代词真正后指的描写与讨论
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作者 曹德和 《北华大学学报(社会科学版)》 2025年第5期1-9,150,共10页
汉语他称代词是否存在真正后指,我国学界争议多年,始终未能达成共识。症结主要在于事实调查不够充分,且研究方法亟待改进。本研究首先利用电子检索手段和电子语料库,大规模搜集与他称代词真正后指相关的语料,然后在严格区分“真正后指... 汉语他称代词是否存在真正后指,我国学界争议多年,始终未能达成共识。症结主要在于事实调查不够充分,且研究方法亟待改进。本研究首先利用电子检索手段和电子语料库,大规模搜集与他称代词真正后指相关的语料,然后在严格区分“真正后指”与“重新指认”的基础上,对汉语中他称代词真正后指的具体表现加以系统梳理和细致描写。事实显示,汉语他称代词真正后指客观存在,通常见于作品标题,与同位短语关系密切。厘清事实后,深入讨论了三个问题:a.真正后指的语用特点;b.真正后指与同位短语的渊源关系;c.真正后指演进历程及其启示。最后指出,注意演绎与归纳、理性思考与实证检验相结合,无论对于本课题还是其他课题,都有着至关重要的方法论意义。 展开更多
关键词 汉语他称代词 真正后指 重新指认 分布特点 同位短语
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极地船舶海水飞沫结冰实验研究进展 被引量:1
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作者 王永魁 白旭 +3 位作者 鲁阳 李锋 薛彦卓 王庆 《哈尔滨工程大学学报》 北大核心 2025年第6期1054-1064,共11页
海水飞沫结冰问题广泛存在于极地船舶航行过程中,并严重危害船舶稳性及人员安全。近年来,随着北极航道交通量的上涨和资源开发活动的增多,船舶面临的结冰问题日益凸显,结冰事故频发。海水飞沫结冰预报模型是建立结冰防护手段、保障航行... 海水飞沫结冰问题广泛存在于极地船舶航行过程中,并严重危害船舶稳性及人员安全。近年来,随着北极航道交通量的上涨和资源开发活动的增多,船舶面临的结冰问题日益凸显,结冰事故频发。海水飞沫结冰预报模型是建立结冰防护手段、保障航行及作业安全的有效手段,其准确性需通过相关结冰实验数据来验证。为此,本文梳理了海水飞沫结冰事件的实地测量及实验室模型实验数据,涉及飞沫的产生与运动、飞沫附着结冰、结冰程度及其影响因素、积冰物理特征及力学特性等方面。分析发现:实验研究呈现出“从定性到定量、从粗放到精细、从局部到整体”的特点,但不同结冰研究间实验数据差异较大;最后从结冰实地数据获取、实验室尺度结冰、全尺度全要素结冰实验等3个方面给出了海水飞沫结冰实验研究的展望,从而为结冰预报模型的发展和防除冰技术的提升提供科学指导和精细输入。 展开更多
关键词 北极航道 极地船舶 海水飞沫 结冰 实地测量 积冰特性 模型实验 研究进展
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海河“23·7”流域性特大洪水地下水影响特征分析 被引量:1
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作者 朱静思 王哲 李宇 《水电能源科学》 北大核心 2025年第2期23-26,共4页
围绕海河“23·7”流域性特大洪水对深浅层地下水的影响特征和暴雨洪水的资源效应问题,基于流域平原区逐日地下水位动态资料,分析了海河流域平原地下水漏斗区、滞洪区等典型区域地下水位的时空变异特征,采用ArcGIS空间分析和水文分... 围绕海河“23·7”流域性特大洪水对深浅层地下水的影响特征和暴雨洪水的资源效应问题,基于流域平原区逐日地下水位动态资料,分析了海河流域平原地下水漏斗区、滞洪区等典型区域地下水位的时空变异特征,采用ArcGIS空间分析和水文分析计算方法,估算了浅层地下水资源的补给量。研究表明,浅层、深层地下水对海河“23·7”流域性特大洪水均有响应,但特点不同。浅层地下水位阶段性跃升明显,深层水位呈持续平稳回升态势,深层回升幅度较浅层明显;暴雨洪水主要补给冲洪积平原河道带等强入渗区域和漏斗区等地势低洼区域的地下水。平原区地下水位响应程度西高东低,变化幅度上西部山前冲洪积平原水位升幅大、东部滨海平原升幅小,变化过程上暴雨结束后西部的山前平原水位持续缓慢上升、东部滨海平原水位总体下降,并采用ArcGIS空间分析和水文分析等计算方法,估算7月28日至8月31日“23·7”洪水补给平原区地下水资源量约111.0×10^(8)m^(3),补给强度为8.64×10^(8)m^(3)/10^(4)km^(2)。研究结果可为科学利用雨洪资源、缓解地下水超采状况提供依据。 展开更多
关键词 海河“23·7”流域性特大洪水 地下水位 影响特征 地下水补给量
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