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“前”“后”的时间指向及时间认知的古今差异
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作者 何亮 《重庆师范大学学报(社会科学版)》 2018年第4期52-59,共8页
认为"前""后"既表示过去又表示将来,是混淆了"前""后"的时空概念。"前""后"的空间或时间义与人们的关注焦点有关,也与其出现的句法环境、与之组合成分的语义特征有关。就... 认为"前""后"既表示过去又表示将来,是混淆了"前""后"的时空概念。"前""后"的空间或时间义与人们的关注焦点有关,也与其出现的句法环境、与之组合成分的语义特征有关。就时间指向而言,"前"均表示时间较早或顺序在先,"后"表示时间较晚或顺序在后。"前""后"所体现的时间认知方式古今并无不同。但是,在汉语史上,"前""后"所体现的"人动时静"认知方式的表达形式有一个由潜隐到显露的发展过程。 展开更多
关键词 时间指向 时空隐喻 语义特征
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考“后” 被引量:1
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作者 张艳 《浙江海洋学院学报(人文科学版)》 2005年第3期10-14,84,共6页
《说文》曰:“后,继体君也。”经过采用形训的方法,结合古代文献,依据“后”字的甲骨文、金文字形,并寻找“后”字词义发展的线索,可以系统地解释“后”字的含义:“后”的本义为“妇女产子,”由此在母系社会被用作对最高首领的称呼,从... 《说文》曰:“后,继体君也。”经过采用形训的方法,结合古代文献,依据“后”字的甲骨文、金文字形,并寻找“后”字词义发展的线索,可以系统地解释“后”字的含义:“后”的本义为“妇女产子,”由此在母系社会被用作对最高首领的称呼,从而引申出“君”义及“继体君”义;由产子时的母前子後引申出“後”义,并造“後”字,因“后”的“继体君”义与“後”相通,加之音同,故常假借“后”为“後;”综合“妇女产子”义、“後”义、及“继体君”义,引申出“天子之妃曰后”。 展开更多
关键词 产子 后土 继体君
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海昏汉简《诗经》研究三题
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作者 陈才 《南京师范大学文学院学报》 2024年第2期62-67,共6页
学术界广泛认可海昏汉简《诗经》为《鲁诗》。从已经公布的部分文本内容来看,海昏汉简《诗经》符合“故”的文本特征,因此,疑为《汉书·艺文志》著录的《鲁故》。海昏汉简《诗经》目录简的编连,应符合古书正文在小题前而小题又在大... 学术界广泛认可海昏汉简《诗经》为《鲁诗》。从已经公布的部分文本内容来看,海昏汉简《诗经》符合“故”的文本特征,因此,疑为《汉书·艺文志》著录的《鲁故》。海昏汉简《诗经》目录简的编连,应符合古书正文在小题前而小题又在大题前的通例,标题简应当置于末尾而不当在前。据海昏汉简《诗经》目录简中“予其惩而八”可知,《周颂·小些》“予其惩而些后患”当断句为“予其惩而,些后患”,与《毛诗》同。 展开更多
关键词 海昏汉简 《诗经》 《鲁故》 编连 予其惩而毖后患
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家属协同干预在抗磷脂综合征合并妊娠患者中的应用效果
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作者 李伏一 肖兰凤 《中国医药导报》 CAS 2024年第5期160-164,共5页
目的探讨家属协同干预在抗磷脂综合征(APS)合并妊娠患者中的应用效果。方法选择2020年1月至2022年12月内蒙古医科大学附属医院收治的100例APS合并妊娠患者,根据随机数字表法将其分为甲组和乙组,每组50例。甲组予以常规护理,乙组在甲组... 目的探讨家属协同干预在抗磷脂综合征(APS)合并妊娠患者中的应用效果。方法选择2020年1月至2022年12月内蒙古医科大学附属医院收治的100例APS合并妊娠患者,根据随机数字表法将其分为甲组和乙组,每组50例。甲组予以常规护理,乙组在甲组基础上行家属协同干预。观察两组干预前后情绪状态、自我护理能力、服药依从性及妊娠并发症发生情况。结果干预后,两组正性负性情绪量表中正性情绪评分高于干预前,负性情绪评分低于干预前,且乙组正性情绪评分高于甲组,负性情绪评分低于甲组,差异有统计学意义(P<0.05);干预后,两组自我护理能力测定量表及中文版8条目Morisky服药依从性量表评分均高于干预前,且乙组高于甲组,差异有统计学意义(P<0.05)。结论家属协同干预可改善APS妊娠者情绪状态、自我护理能力及用药依从性,并可减少其他妊娠并发症。 展开更多
关键词 抗磷脂综合征 妊娠 家属协同干预 服药依从性 并发症
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Shear mechanical properties and frictional sliding responses of rough joint surfaces under dynamic normal displacement conditions
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作者 ZHU Qiang YIN Qian +9 位作者 TAO Zhi-gang HE Man-chao ZHENG Bo-wen JING Hong-wen REN Shu-lin ZHANG Qiang MENG Bo BAI Dong-feng WU Sai-sai WU Jiang-yu 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2393-2410,共18页
A comprehensive understanding of the dynamic frictional characteristics in rock joints under high normal load and strong confinement is essential for ensuring the safety of deep engineering construction and mitigating... A comprehensive understanding of the dynamic frictional characteristics in rock joints under high normal load and strong confinement is essential for ensuring the safety of deep engineering construction and mitigating geological disasters.This study conducted shear experiments on rough rock joints under displacement-controlled dynamic normal loads,investigating the shear behaviors of joints across varying initial normal loads,normal loading frequencies,and normal loading amplitudes.Experimental results showed that the peak/valley shear force values increased with initial normal loads and normal loading frequencies but showed an initial increase followed by a decrease with normal loading amplitudes.Dynamic normal loading can either increase or decrease shear strength,while this study demonstrates that higher frequencies lead to enhanced friction.Increased initial normal loading and normal loading frequency result in a gradual decrease in joint roughness coefficient(JRC)values of joint surfaces after shearing.Positive correlations existed between frictional energy dissipation and peak shear forces,while post-shear joint surface roughness exhibited a negative correlation with peak shear forces through linear regression analysis.This study contributes to a better understanding of the sliding responses and shear mechanical characteristics of rock joints under dynamic disturbances. 展开更多
关键词 dynamic normal displacement shear strength variations phase lag phenomenon STICK-SLIP
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Prognositic value of anoikis and tumor immune microenvironment-related gene in the treatment of osteosarcoma
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作者 WANG Dong DENG Qing +7 位作者 PENG Yi TONG Zhaochen LI Zixin HUANG Liping ZENG Jin LI Jinsong MIAO Jinglei CHEN Shijie 《中南大学学报(医学版)》 CAS CSCD 北大核心 2024年第5期758-774,共17页
Objective:Osteosarcoma is a highly aggressive primary malignant bone tumor commonly seen in children and adolescents,with a poor prognosis.Anchorage-dependent cell death(anoikis)has been proven to be indispensable in ... Objective:Osteosarcoma is a highly aggressive primary malignant bone tumor commonly seen in children and adolescents,with a poor prognosis.Anchorage-dependent cell death(anoikis)has been proven to be indispensable in tumor metastasis,regulating the migration and adhesion of tumor cells at the primary site.However,as a type of programmed cell death,anoikis is rarely studied in osteosarcoma,especially in the tumor immune microenvironment.This study aims to clarify prognostic value of anoikis and tumor immune microenvironment-related gene in the treatment of osteosarcoma.Methods:Anoikis-related genes(ANRGs)were obtained from GeneCards.Clinical information and ANRGs expression profiles of osteosarcoma patients were sourced from the therapeutically applicable research to generate effective therapies and Gene Expression Omnibus(GEO)databases.ANRGs highly associated with tumor immune microenvironment were identified by the estimate package and the weighted gene coexpression network analysis(WGCNA)algorithm.Machine learning algorithms were performed to construct long-term survival predictive strategy,each sample was divided into high-risk and low-risk subgroups,which was further verified in the GEO cohort.Finally,based on single-cell RNA-seq from the GEO database,analysis was done on the function of signature genes in the osteosarcoma tumor microenvironment.Results:A total of 51 hub ANRGs closely associated with the tumor microenvironment were identified,from which 3 genes(MERTK,BNIP3,S100A8)were selected to construct the prognostic model.Significant differences in immune cell activation and immune-related signaling pathways were observed between the high-risk and low-risk groups based on tumor microenvironment analysis(all P<0.05).Additionally,characteristic genes within the osteosarcoma microenvironment were identified in regulation of intercellular crosstalk through the GAS6-MERTK signaling pathway.Conclusion:The prognostic model based on ANRGs and tumor microenvironment demonstrate good predictive power and provide more personalized treatment options for patients with osteosarcoma. 展开更多
关键词 ANOIKIS tumor immune microenvironment BIOINFORMATICS PROGNOSIS OSTEOSARCOMA
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CFD modeling of gas−liquid flow phenomenon in lead smelting oxygen-enriched side-blown furnace
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作者 Zhen-yu ZHU Ping ZHOU +3 位作者 Xing-bang WAN Zhuo CHEN Ling ZHANG Shi-bo KUANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2671-2685,共15页
A validated numerical model was established to simulate gas−liquid flow behaviors in the oxygen-enriched side-blown bath furnace.This model included the slip velocity between phases and the gas thermal expansion effec... A validated numerical model was established to simulate gas−liquid flow behaviors in the oxygen-enriched side-blown bath furnace.This model included the slip velocity between phases and the gas thermal expansion effect.Its modeling results were verified with theoretical correlations and experiments,and the nozzle-eroded states in practice were also involved in the analysis.Through comparison,it is confirmed that the thermal expansion effect influences the flow pattern significantly,which may lead to the backward motion of airflow and create a potential risk to production safety.Consequently,the influences of air injection velocity and furnace width on airflow behavior were investigated to provide operating and design guidance.It is found that the thin layer melt,which avoids high-rate oxygen airflow eroding nozzles,shrinks as the injection velocity increases,but safety can be guaranteed when the velocity ranges from 175 to 275 m/s.Moreover,the isoline patterns and heights of thin layers change slightly when the furnace width increases from 2.2 to 2.8 m,indicating that the furnace width shows a limited influence on production safety. 展开更多
关键词 multiphase flow horizontal gas injection backward motion of airflow gas thermal expansion side-blown furnace lead smelting
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Load-bearing characteristics and energy evolution of fractured rock masses after granite and sandstone grouting
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作者 WU Xu-kun ZHAO Guang-ming +4 位作者 MENG Xiang-rui LIU Chong-yan LIU Zhi-xi HUANG Shun-jie ZHANG Qi-hang 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2810-2825,共16页
Experiments on grouting-reinforced rock mass specimens with different particle sizes and features were carried out in this study to examine the effects of grouting reinforcement on the load-bearing characteristics of ... Experiments on grouting-reinforced rock mass specimens with different particle sizes and features were carried out in this study to examine the effects of grouting reinforcement on the load-bearing characteristics of fractured rock mass.The strength and deformation features of grouting-reinforced rock mass were analyzed under different loading manners;the energy evolution mechanism of grouting-reinforced rock mass specimens with different particle sizes and features was investigated;the energy dissipation ratio and post-peak stress decreasing rate were employed to evaluate the bearing stability of grouting-reinforced rock mass.The results show that the strength and ductility of granite-reinforced rock mass(GRM)under biaxial loading are higher than that of sandstone-reinforced rock mass(SRM)under uniaxial loading.Besides,the energy evolution characteristics of grouting-reinforced rock mass under uniaxial and biaxial loading mainly could be divided into early,middle,and late stages.In the early stage,total,elastic,and dissipation energies were quite small with flatter curves;in the middle stage,elastic energy increased rapidly,whereas dissipation energy increased slowly;in the late stage,dissipation energy increased sharply.The energy dissipation ratio was used to represent the pre-peak plastic deformation.Under uniaxial loading,this ratio increased as the particle size increased and the pre-peak plastic deformation of grouting-reinforced rock mass became larger;under biaxial loading,it dropped as the particle size increased,and the pre-peak plastic deformation of grouting-reinforced rock mass became smaller.The post-peak stress decline rate A_(v) was used to assess the post-peak bearing performance of grouting-reinforced rock mass.Under uniaxial loading,parameter A_(v) exhibited reduction as the particle size kept increasing,and the ability of post-peak of grouting-reinforced rock mass to allow deformation development was greater,and the bearing capacity was greater;under biaxial loading,A_(v) increased with the particle size,and the ability of post-peak of grouting-reinforced rock mass to allow deformation development was low and the bearing capacity was reduced.The findings are considered instrumental in improving the stability of the roadway-surrounding rock by granite and sandstone grouting. 展开更多
关键词 grouting-reinforced rock mass particle size energy dissipation ratio post-peak stress decreasing rate load-bearing characteristics
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A Prognostic Model Based on Colony Stimulating Factors-related Genes in Triple-negative Breast Cancer
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作者 GUO Yu-Xuan WANG Zhi-Yu +7 位作者 XIAO Pei-Yao ZHENG Chan-Juan FU Shu-Jun HE Guang-Chun LONG Jun WANG Jie DENG Xi-Yun WANG Yi-An 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2024年第10期2741-2756,共16页
Objective Triple-negative breast cancer(TNBC)is the breast cancer subtype with the worst prognosis,and lacks effective therapeutic targets.Colony stimulating factors(CSFs)are cytokines that can regulate the production... Objective Triple-negative breast cancer(TNBC)is the breast cancer subtype with the worst prognosis,and lacks effective therapeutic targets.Colony stimulating factors(CSFs)are cytokines that can regulate the production of blood cells and stimulate the growth and development of immune cells,playing an important role in the malignant progression of TNBC.This article aims to construct a novel prognostic model based on the expression of colony stimulating factors-related genes(CRGs),and analyze the sensitivity of TNBC patients to immunotherapy and drug therapy.Methods We downloaded CRGs from public databases and screened for differentially expressed CRGs between normal and TNBC tissues in the TCGA-BRCA database.Through LASSO Cox regression analysis,we constructed a prognostic model and stratified TNBC patients into high-risk and low-risk groups based on the colony stimulating factors-related genes risk score(CRRS).We further analyzed the correlation between CRRS and patient prognosis,clinical features,tumor microenvironment(TME)in both high-risk and low-risk groups,and evaluated the relationship between CRRS and sensitivity to immunotherapy and drug therapy.Results We identified 842 differentially expressed CRGs in breast cancer tissues of TNBC patients and selected 13 CRGs for constructing the prognostic model.Kaplan-Meier survival curves,time-dependent receiver operating characteristic curves,and other analyses confirmed that TNBC patients with high CRRS had shorter overall survival,and the predictive ability of CRRS prognostic model was further validated using the GEO dataset.Nomogram combining clinical features confirmed that CRRS was an independent factor for the prognosis of TNBC patients.Moreover,patients in the high-risk group had lower levels of immune infiltration in the TME and were sensitive to chemotherapeutic drugs such as 5-fluorouracil,ipatasertib,and paclitaxel.Conclusion We have developed a CRRS-based prognostic model composed of 13 differentially expressed CRGs,which may serve as a useful tool for predicting the prognosis of TNBC patients and guiding clinical treatment.Moreover,the key genes within this model may represent potential molecular targets for future therapies of TNBC. 展开更多
关键词 triple-negative breast cancer colony stimulating factors prognostic model tumor microenvironment drug sensitivity
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Osteology of Turfanodon bogdaensis (Dicynodontia)
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作者 SHI Yu-Tai LIU Jun 《古脊椎动物学报(中英文)》 CSCD 北大核心 2024年第3期186-200,共15页
Within the dicynodont genus Turfanodon,there are two recognized species,T.bogdaensis and T.jiufengensis.Both species are known by relatively complete cranial materials,but the mandibles and most postcranial bones have... Within the dicynodont genus Turfanodon,there are two recognized species,T.bogdaensis and T.jiufengensis.Both species are known by relatively complete cranial materials,but the mandibles and most postcranial bones have been described only for T.jiufengensis.This paper reports new dicynodont specimens from Turpan,Xinjiang,referring them to T.bogdaensis.They can clearly be differentiated from T.jiufengensis by the flatter lateral surface of the snout region,a prominent swelling on the lateral dentary shelf,and the rounded femoral head.The diagnosis of Turfanodon is revised.The combination of a flat circumorbital rim,posterior portion of anterior pterygoid rami with converging ventral ridges,and a possible autapomorphy,a deep notch on scapula forming procoracoid foramen,are confirmed.It also differentiated from all dicynodonts other than Myosaurus,Kembawacela and Lystrosaurus by having accessory ridges lateral to the median palatal ridge. 展开更多
关键词 Turpan Xinjiang Lopingian Permian Guodikeng Formation Dicynodontia Turfanodon osteology postcranial skeleton
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“绘事后素”语义考辨
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作者 高查清 蔡满园 《五邑大学学报(社会科学版)》 2023年第3期72-76,94,共6页
以朱熹和郑玄为代表的两派对《论语》中“绘事后素”之“后素”在解读上截然对立。前者解“素”为“粉地”,名词,解“后素”为“后于素”,即布好粉地然后在上面作画;后者解“素”为“以素粉勾勒”,动词,解“后素”为“后素之”,即绘画... 以朱熹和郑玄为代表的两派对《论语》中“绘事后素”之“后素”在解读上截然对立。前者解“素”为“粉地”,名词,解“后素”为“后于素”,即布好粉地然后在上面作画;后者解“素”为“以素粉勾勒”,动词,解“后素”为“后素之”,即绘画中“布完众色之后以素粉分布其间”。二者均没有充分关注孔子“起予者商也”之内涵,亦没有将“绘事后素”之语义与整个对话语境结合起来加以审视。基于对《论语》“绘事后素”章节文本结构的逻辑分析,从对话的连贯性和完整性参悟双方意图,推敲其“言外之意”,认为占据学术主流的“朱派”观点理据不足,“郑派”则对“后素”的本义作出了准确判断,惜乎对“素以为绚兮”的解释仍有失偏颇。 展开更多
关键词 绘事后素 逻辑分析 言外之意 语义
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“不久前”和“不久后”的功能差异及其成因
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作者 宗守云 车飞 《汉语学习》 CSSCI 北大核心 2023年第5期40-47,共8页
“不久前”和“不久后”都是时间连接成分,用作时间状语可以饰句、饰谓,用作定语时和时间状语语义性质相同。“不久前”只能充当时间修饰语,只能指向过去事件,可以出现在篇首。“不久后”具有时间修饰和事件系联双重功能,可以系联将来事... “不久前”和“不久后”都是时间连接成分,用作时间状语可以饰句、饰谓,用作定语时和时间状语语义性质相同。“不久前”只能充当时间修饰语,只能指向过去事件,可以出现在篇首。“不久后”具有时间修饰和事件系联双重功能,可以系联将来事件,不能出现在篇首。“不久前”和“不久后”的功能差异是“不久”的模糊性和“前”“后”的认知差异性共同促成的。 展开更多
关键词 促转模式 程度副词 形化功效
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《蕲春语》《说文》后出字中的方言本字职用问题
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作者 韩琳 《汉字汉语研究》 2023年第2期66-78,128,共14页
《蕲春语》是黄侃考察湖北方言俗语之作。其中使用很多字体分类术语正字以溯本,正音以溯源。本论文在重点考察《说文》后出字的基础上,将溯本和溯源相结合,对《蕲春语》以及方言本字相关问题作深入探讨,以期为方言文献中的字词关系研究... 《蕲春语》是黄侃考察湖北方言俗语之作。其中使用很多字体分类术语正字以溯本,正音以溯源。本论文在重点考察《说文》后出字的基础上,将溯本和溯源相结合,对《蕲春语》以及方言本字相关问题作深入探讨,以期为方言文献中的字词关系研究提供参考。 展开更多
关键词 蕲春语 说文 后出字
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“古今字”内涵异解的学史梳理和学理阐释
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作者 温敏 《汉字汉语研究》 2023年第2期79-94,128,F0003,共18页
现代研究对传统训诂学术语“古今字”的核心指向义在“历时同词异字”之外存在异解。文章从学史上“古今字”“分别文”“后出字”“后起字”的术语关系中,梳理其内涵义产生异解的过程,以正本清源,明其本旨。同时从学理逻辑学角度,说明... 现代研究对传统训诂学术语“古今字”的核心指向义在“历时同词异字”之外存在异解。文章从学史上“古今字”“分别文”“后出字”“后起字”的术语关系中,梳理其内涵义产生异解的过程,以正本清源,明其本旨。同时从学理逻辑学角度,说明产生这种异解的原因,可以概括为不同视角下同一材料具多维属性不等于概念的同一或对立。 展开更多
关键词 古今字 分别文 后起字
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论范晔对东汉“党人”的编纂及评价
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作者 王亮军 《南都学坛(南阳师范学院人文社会科学学报)》 2023年第4期18-29,共12页
范晔在《后汉书》中增设《党锢列传》并以之为核心对东汉的“党人”群体进行了记载。对于“党人”的编纂,范晔在《党锢列传》传首用长序、采谣谚来交代“党锢”的起因与经过,并以之提携全传,又择“三君、八俊”等核心“党人”为传主,以... 范晔在《后汉书》中增设《党锢列传》并以之为核心对东汉的“党人”群体进行了记载。对于“党人”的编纂,范晔在《党锢列传》传首用长序、采谣谚来交代“党锢”的起因与经过,并以之提携全传,又择“三君、八俊”等核心“党人”为传主,以此展现“党锢之祸”的全貌,对于其他“党人”,则以类(德性)相从进行合传。范晔对东汉“党人”的这种编纂方式使其在《后汉书》中形成了以《党锢》为核心的“党人传”记载结构,在这个结构中,“党事”始末之主次线索清晰,“党锢”人物之行事编排严密,东汉后期之历史发展面貌丰富。同时,在相关传记中范晔又以大量史论表达了他对东汉“党锢之祸”影响东汉历史走向,以及东汉“党人”出处进退及其精神的看法。范晔对东汉党锢事件及人物的记载,最能体现他的历史编纂水平。 展开更多
关键词 范晔 《后汉书》 《党锢列传》 “党人” 历史编纂
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时间词“时”和“後”的语法化 被引量:116
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作者 江蓝生 《中国语文》 CSSCI 北大核心 2002年第4期291-301,共11页
本文考察了在汉语假设助词系统发展的历史中,曾有时间词加入的事实。文中分析了诱发时间词"时"与"後"语法化的句法环境和内部机制;揭示了"时"与"後"语法化的过程以及随着语法化程度的不断加深... 本文考察了在汉语假设助词系统发展的历史中,曾有时间词加入的事实。文中分析了诱发时间词"时"与"後"语法化的句法环境和内部机制;揭示了"时"与"後"语法化的过程以及随着语法化程度的不断加深其语法功能不断扩大的事实。文章还论证了"後"虽被"呵"取代,但与"呵"并无来源关系。指出由时间范畴进入假设范畴,是汉语跟其他一些语言共有的语用认知规律。 展开更多
关键词 时间词 “时” “後” 语法化 假设助词
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汉语“前、后”的时间指向认知研究 被引量:5
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作者 曹琳琳 邢苗苗 《汉语学习》 CSSCI 北大核心 2017年第5期104-112,共9页
汉语中表示空间方位的"前、后"发展出表时间的功能后,既可表将来,也可表过去。如"前"在"前景、前途"中表将来,而在"前世、前人"中表过去。"后"在"后世、后人"中表将来,而... 汉语中表示空间方位的"前、后"发展出表时间的功能后,既可表将来,也可表过去。如"前"在"前景、前途"中表将来,而在"前世、前人"中表过去。"后"在"后世、后人"中表将来,而在"后退、往后"中可表过去。王灿龙(2016)认为,以往使用"时间在动"和"人在动"两个隐喻模式并不能很好地解释汉语中"前、后"在表示时间时的复杂现象。本文在王文的基础上进一步指出,这种矛盾实际上并不存在。"前"表将来和"后"表过去,来源于人们将想象的"虚拟空间"和时间混为一谈。"虚拟空间"是相对"现实空间"而言,后者处于我们感知范围之内,前者超出我们的感知范围。"前景、前途"表示将来、"后退、往后"表示过去时,本质上是表示"虚拟空间"上的"前方"和"后方"。 展开更多
关键词 “前” “后” 时间 空间
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Dynamic behavior of rock during its post failure stage in SHPB tests 被引量:13
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作者 周子龙 赵源 +3 位作者 江益辉 邹洋 蔡鑫 李地元 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第1期184-196,共13页
In order to investigate the micro-process and inner mechanism of rock failure under impact loading, the laboratory tests were carried out on an improved split Hopkinson pressure bar (SHPB) system with synchronized m... In order to investigate the micro-process and inner mechanism of rock failure under impact loading, the laboratory tests were carried out on an improved split Hopkinson pressure bar (SHPB) system with synchronized measurement devices including a high-speed camera and a dynamic strain meter. The experimental results show that the specimens were in the state of good stress equilibrium during the post failure stage even when visible cracks were forming in the specimens. Rock specimens broke into strips but still could bear the external stress and keep force balance. Meanwhile, numerical tests with particle flow code (PFC) revealed that the failure process of rocks can be described by the evolution of micro-fractures. Shear cracks emerged firstly and stopped developing when the external stress was not high enough. Tensile cracks, however, emerged when the rock specimen reached its peak strength and played an important role in controlling the ultimate failure during the post failure stage. 展开更多
关键词 rock dynamics post failure stress equilibrium crack evolution particle flow code
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Effects of Trichosporon sp. in Combination with Calcium and Fungicide on Biocontrol of Postharvest Diseases in Apple Fruits 被引量:24
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作者 田世平 范青 +1 位作者 徐勇 汪沂 《Acta Botanica Sinica》 CSCD 2001年第5期501-505,共5页
The capability of yeast Trichosporon sp., an antagonist isolated from peach fruit, in biological control was evaluated in apple ( Malus domestica Borkh. cv. Fuji) fruits, when inoculated with different concentr... The capability of yeast Trichosporon sp., an antagonist isolated from peach fruit, in biological control was evaluated in apple ( Malus domestica Borkh. cv. Fuji) fruits, when inoculated with different concentrations of Botrytis cinerea Pers. and Penicillium expansum (Link) Thom, as well as in combination with calcium and fungicide. The concentrations of the yeast cells and pathogen spores obviously influenced disease incidence and lesion development in apples. There was a significant negative correlation between concentrations of the yeast cells and infectivity of the pathogens. When the yeast cell suspensions reached the concentration of 10 8 colony_forming units (CFU) /mL, there was no infection caused by B. cinerea and P. expansum with spore concentrations below 10 6 spores/mL in apple fruits. The yeast at concentrations of 10 6-10 7 CFU/mL in combination with fungicide (iprodione at 50 μL/L) provided control of decay caused by B. cinerea and P. expansum better than separate application. Effect of controlling gray mould and blue mould rots was enhanced when Trichosporon sp., even at low concentration of 10 5 CFU/mL, was applied in the presence of 1%-2% CaCl 2 in an aqueous suspension. 展开更多
关键词 Trichosporon sp. CALCIUM IPRODIONE postharvest diseases APPLE
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宋仁宗郭皇后被废案探议 被引量:10
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作者 杨果 刘广丰 《史学集刊》 CSSCI 北大核心 2008年第1期56-60,共5页
宋仁宗郭皇后是宋代第一位被废黜的皇后,郭皇后被废事件是仁宗时期宫廷矛盾掺杂朝臣斗争的产物,其主要原因是仁宗不满刘太后的垂帘听政,同时也与仁宗作为少年即位的皇帝,与其母亲、妻子之间的感情纠葛有关,另外,朝中大臣的介入也起了推... 宋仁宗郭皇后是宋代第一位被废黜的皇后,郭皇后被废事件是仁宗时期宫廷矛盾掺杂朝臣斗争的产物,其主要原因是仁宗不满刘太后的垂帘听政,同时也与仁宗作为少年即位的皇帝,与其母亲、妻子之间的感情纠葛有关,另外,朝中大臣的介入也起了推波助澜的作用。 展开更多
关键词 宋仁宗 郭皇后 刘太后 废黜
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