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HAN基电控固体推进剂电化学性能对燃烧性能的影响
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作者 郭昊琪 杨玉林 《固体火箭技术》 CAS CSCD 北大核心 2024年第3期341-347,共7页
硝酸羟胺(HAN)基电控固体推进剂是一种以HAN为主要氧化剂的新型智能推进剂,通过外加电源控制其燃烧速率与启停。为探索电化学性能与燃烧性能间的关系,在研究推进剂的离子迁移率、过电位的变化规律的基础上,将其与推进剂的点火电压、点... 硝酸羟胺(HAN)基电控固体推进剂是一种以HAN为主要氧化剂的新型智能推进剂,通过外加电源控制其燃烧速率与启停。为探索电化学性能与燃烧性能间的关系,在研究推进剂的离子迁移率、过电位的变化规律的基础上,将其与推进剂的点火电压、点火延迟进行关联。研究发现,推进剂在外加低电压(1.6~2.8 V)刺激下,离子迁移率与电压大小正相关,推进剂基体的改良在提高离子迁移率方面的效果大于离子掺杂。在燃烧性能方面,离子迁移率影响点火电压,过电位决定点火延迟;离子迁移率越高,点火时,推进剂的电流密度与反应活性越高;当迁移率由0.09 mm^(2)·s^(-1)·V^(-1)升高至0.16 mm^(2)·s^(-1)·V^(-1)时,点火电压由210 V降至70 V,有利于拓宽电控固体推进剂的应用范围;点火电压一定时,推进剂过电位越小,电分解速率越大,点火延迟越小,当过电位由0.67 V降至0.51 V时,点火延迟由1.68 s降至0.31 s,有利于推进剂满足快速响应的战略需求。 展开更多
关键词 电控固体推进剂 硝酸羟胺 离子迁移率 过电位 电控燃烧
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新型HAN基液体推进剂EMP⁃01液滴电点火特性 被引量:1
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作者 刘冲 姚天亮 +2 位作者 薛晓春 余永刚 张欣尉 《含能材料》 EI CAS CSCD 北大核心 2023年第9期895-902,共8页
为探究新型硝酸羟胺(HAN)基液体推进剂EMP‑01液滴点火特性,搭建了通过将液滴静置在半球形凹槽内并插入电极的液滴电点火实验平台,在液滴直径6.5 mm、电极间距0.5 mm、电压加载速率为86.31 V∙s-1的工况下,研究了EMP‑01液滴的电点火燃烧特... 为探究新型硝酸羟胺(HAN)基液体推进剂EMP‑01液滴点火特性,搭建了通过将液滴静置在半球形凹槽内并插入电极的液滴电点火实验平台,在液滴直径6.5 mm、电极间距0.5 mm、电压加载速率为86.31 V∙s-1的工况下,研究了EMP‑01液滴的电点火燃烧特性,确定了着火延迟时间;同时,不改变液滴直径以及电极间距,研究了电压加载速率为34.20~246.37 V∙s^(-1)时液滴着火延迟时间与燃烧过程的变化规律。结果表明,电点火燃烧中,EMP‑01液滴分依次经历为加热、热分解、燃烧3个阶段,并且在热分解阶段会产生周期性的膨胀收缩。电压加载速率为34.20 V∙s^(-1)时,EMP‑01液滴无法成功点火;电压加载速率为49.49~246.37 V∙s^(-1)时,随着电压加载速率增加,EMP‑01液滴着火延迟时间不断减小,且减小速率逐渐变缓。 展开更多
关键词 han基推进剂 电点火特性 液体推进剂 燃烧
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Detecting the polymorphism sites of p53 and Fas genes of Han population in Zhejiang province 被引量:5
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作者 Yang Zhuo Xingye Zeng +1 位作者 Dadao Huang Xuexue Zhou 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第1期90-93,共4页
BACKGROUND: It is of significance for single nucleotide polymorphisms (SNPs), a difference of rank, which exists widely in biology, genetics and other fields. OBJECTIVE: To detect polymorphism sites in exon-4 of p... BACKGROUND: It is of significance for single nucleotide polymorphisms (SNPs), a difference of rank, which exists widely in biology, genetics and other fields. OBJECTIVE: To detect polymorphism sites in exon-4 of p53 gene, promotor of Fas gene and intron-7 of Fas gene of healthy people in Han nationality in Zhejiang province. DESIGN: Simple random sampling. SETTING: Department of Surgery of the 118 Hospital of Chinese PLA.PARTICIPANTS: A total of 80 healthy people in Han nationality were selected from hospitals in Zhejiang province from August 2005 to January 2006. There were 43 males and 37 females aged from 3 to 78 years with the mean age of 39.5 years, and all subjects were consent. DNA which was used in genetic analysis was selected from peripheral venous blood of all subjects and maintained at -20℃.METHODS: Polymorphism sites in exon-4 of p53 gene, promotor of Fas gene and intron-7 of Fas gene were detected with directly DNA sequencing technique. MAIN OUTCOME MEASURES : Polymorphism sites in exon-4 of p53 gene, promotor of Fas gene and intron-7 of Fas gene of healthy people in Han nationality in Zhejiang province. RESULTS: A total of 80 samples were involved in the final analysis. SNPs sites were found at the 119^th base of exon-4 of p53 gene (the 72^nd codon of p53 gene), the 670^th base of upper start codon in promotor of Fas gene (Fas-670), and the 995^th base of intron-7 of Fas gene, especially SNPs in the 995^th base of intron-7 pf Fas gene, i.e. C→A transversion, was a new site.CONCLUSION : One unknown SNPs site is discovered in intron-7 of Fas gene of people in Han nationality in Zhejiang province. This study also proves that the 72^nd codon exists in p53 gene and the -670 polymorphism site exists in promotor of Fas gene. 展开更多
关键词 GENE Detecting the polymorphism sites of p53 and Fas genes of han population in Zhejiang province
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Angiotensin-converting enzyme gene polymorphism and middle cerebral artery stenosis in a Chinese Han population
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作者 Chunshu Rong Yingqi Xing +4 位作者 Xinmei Jiang Juan Wang Baoshan Gao Jianjun Zhao Kangding Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第15期1410-1417,共8页
The angiotensin-converting enzyme gene is a candidate gene of stroke. The present study involved 62 healthy volunteers and 148 patients with middle cerebral artery stenosis as confirmed by brain color ultrasound from ... The angiotensin-converting enzyme gene is a candidate gene of stroke. The present study involved 62 healthy volunteers and 148 patients with middle cerebral artery stenosis as confirmed by brain color ultrasound from a Han population in North China, and determined the peripheral blood angiotensin-converting enzyme genotype using PCR-restriction fragment length polymorphism analysis. The results showed that the frequencies of the DD genotype and D allele were increased in patients with middle cerebral artery stenosis, but the difference was not statistically significant compared with healthy controls. The findings of this study on the relationship between stroke genes and middle cerebral artery stenosis indicate no significant correlation between the frequencies of the DO genotype and D allele of angiotensin-converting enzyme and middle cerebral artery stenosis in this Han population from North China. In the future, studies will be carried out to investigate correlations between multiple stroke candidate gene synergy and middle cerebral artery stenosis to provide a foundation for the development of gene therapy. 展开更多
关键词 neural regeneration brain injury STROKE angiotensin-converting enzyme GENE POLYMORPHISM middle cerebral artery angiostenosis North China han population NEUROREGENERATION
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Study of Professor Han Fei’s medication rules in treating infantile epilepsy
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作者 Xin Huang Fei Han 《Journal of Hainan Medical University》 2021年第18期49-54,共6页
Objective:By data mining,to analyze the characteristics of Professor Han Fei’s medication in the treatment of children with epilepsy,to explore the rules of medication,in order to provide reference for clinical treat... Objective:By data mining,to analyze the characteristics of Professor Han Fei’s medication in the treatment of children with epilepsy,to explore the rules of medication,in order to provide reference for clinical treatment of children with epilepsy by Chinese medicine.Methods:From January 2008 to March 2021,we collected the diagnosis and treatment data of the children with epilepsy who were treated by Professor Han Fei in the outpatient department of Guang’Anmen Hospital of Chinese Academy of Medical Sciences.Using the software of IBM SPSS Statistics 24.0 and IBM SPSS Modeler 18.0,the characteristics and rules of Professor Hanfei’s Chinese materia medica used were summarized through the descriptive analysis,correlation analysis and cluster analysis of drug cumulative frequency,drug flavor,drug channel tropism and efficacy.Results:A total of 224 cases were included in this study,excluding 1 case with other neurological disorders.Finally,223 prescriptions were included,involving 176 kinds of Chinese materia medica and the total medication frequency was 4712.The first 10 highfrequency Chinese materia medica were Chaihu(95.52%),Bombyx batryticatus(94.17%),keels(83.41%),oysters(72.65%),earthworm(72.20%),fructus aurantii(66.37%),Scorpion(64.57%),Gastrodia elata(60.99%),Acorus gramineus(59.19%)and Dannan Xing(58.30%).The main Chinese materia medica used were mainly for suppressing hyperactive liver for calming endogenous wind,relieving exterior syndromes and tranquillizing mind.The medicine properties were mainly to be flat,slight cold,pungent,bitter and willing,and they were mainly for liver,lung and heart meridian tropism.Correlation Analysis:Bupleurum chinense,Bombyx batryticatus,Dragon Bone,oyster as its core medicine group,Semen Ziziphi spinosae and semen platycladi are effective strong correlation medicine pair.Three medicine combinations were obtained by cluster analysis.Conclusion:Hanshi has the characteristics of“calming liver,tranquilizing mind,calming endogenous wind,removing the phlegm and extravasated blood”in treating epilepsy. 展开更多
关键词 EPILEPSY Medication analysis Data mining Traditional Chinese medicine han Fei
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Recruiting Talent to Rejuvenate the Han Dynasty
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《China Today》 2001年第12期34-41,共8页
关键词 Recruiting Talent to Rejuvenate the han Dynasty
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Haplotype and Genetic Analysis of 41 Y-STR Loci in the Wuwei Han Population from Gansu Province,China
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作者 Lu-yao LI Sheng-gui FAN +4 位作者 Hui GONG Xing FAN De-chun WANG Neng-xiu LI Fu-quan JIA 《Current Medical Science》 SCIE CAS 2023年第1期184-190,共7页
Objective Y-Chromosomal short tandem repeat polymorphism(Y-STR)analysis plays an indispensable role in the identification of male individuals,population genetics,and biogeographic research.While profiles of many popul... Objective Y-Chromosomal short tandem repeat polymorphism(Y-STR)analysis plays an indispensable role in the identification of male individuals,population genetics,and biogeographic research.While profiles of many populations based on Y-STR markers in human genomes are ample,haplotype data for the Wuwei Han are still scarce.Methods In this study,2180 unrelated Wuwei Han male individuals residing in Gansu Province,China were collected and genotyped using the novel Microreader™40Y Plus ID system.Phylogenetic relationship reconstructions,multidimensional scaling(MDS),and heatmap analysis were performed based on the genetic distance(Rst)values between our studied population and other populations of the Ymax module in the Y-STR Haplotype Reference Database(YHRD).Results A total of 2129 unique haplotypes were obtained,and the haplotype diversity(HD)and discrimination capacity(DC)for the Wuwei Han were 0.9999 and 0.9931,respectively.Conclusion Our results demonstrate that the Wuwei Han population had intimate genetic relationships with East Asians,especially the geographically close Han populations.Overall,this Y-Chromosomal assay gives valuable information about paternal lineages in male individual tracking and genealogical database construction. 展开更多
关键词 MicroreaderTM 40Y Plus ID system Y-STR haplotype Y-InDel Wuwei han population genetics
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Comparative study of type 2 diabetes mellitus-associated gut microbiota between the Dai and Han populations
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作者 Ling-Tong Tang Lei Feng +6 位作者 Hui-Ying Cao Rui Shi Bei-Bei Luo Yan-Bi Zhang Yan-Mei Liu Jian Zhang Shuang-Yue Li 《World Journal of Diabetes》 SCIE 2023年第12期1766-1783,共18页
BACKGROUND The global prevalence of type 2 diabetes mellitus(T2DM)is increasing.T2DM is associated with alterations of the gut microbiota,which can be affected by age,illness,and genetics.Previous studies revealed tha... BACKGROUND The global prevalence of type 2 diabetes mellitus(T2DM)is increasing.T2DM is associated with alterations of the gut microbiota,which can be affected by age,illness,and genetics.Previous studies revealed that there are discriminating microbiota compositions between the Dai and the Han populations.However,the specific gut microbiota differences between the two populations have not been elucidated.AIM To compare the gut microbiota differences in subjects with and without T2DM in the Dai and Han populations.METHODS A total of 35 subjects of the Han population(including 15 healthy children,8 adult healthy controls,and 12 adult T2DM patients)and 32 subjects of the Dai population(including 10 healthy children,10 adult healthy controls,and 12 adult T2DM patients)were enrolled in this study.Fasting venous blood samples were collected from all the subjects for biochemical analysis.Fecal samples were collected from all the subjects for DNA extraction and 16S rRNA sequencing,which was followed by analyses of the gut microbiota composition.RESULTS No significant difference in alpha diversity was observed between healthy children and adults.The diversity of gut microbiota was decreased in T2DM patients compared to the healthy adults in both the Dai and Han populations. There was a significant difference in gut microbiota between healthy children and healthy adults in the Hanpopulation with an increased abundance of Bacteroidetes and decreased Firmicutes in children. However, thisdifference was less in the Dai population. Significant increases in Bacteroidetes in the Han population and Proteobacteriain the Dai population and decreases in Firmicutes in both the Han and Dai population were observed inT2DM patients compared to healthy adults. Linear discriminant analysis Effect Size analysis also showed that thegut microbiota was different between the Han and Dai populations in heathy children, adults, and T2DM patients.Four bacteria were consistently increased and two consistently decreased in the Han population compared to theDai population.CONCLUSION Differences in gut microbiota were found between the Han and Dai populations. A significant increase inBacteroidetes was related to the occurrence of T2DM in the Han population, while a significant increase in Proteobacteriawas related to the occurrence of T2DM in the Dai population. 展开更多
关键词 Gut microbiota Type 2 diabetes mellitus Dai population han population GENETICS ETHNIC
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Beyond Morality:Han Fei’s Unconventional Insights Into Human Nature
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作者 ZHANG Wenhao 《Cultural and Religious Studies》 2023年第12期611-615,共5页
Han Fei presented a thought-provoking perspective on human nature and its implications for governance.Departing from traditional moral doctrines,Han Fei’s“non-moralistic”philosophy posited that human nature is inhe... Han Fei presented a thought-provoking perspective on human nature and its implications for governance.Departing from traditional moral doctrines,Han Fei’s“non-moralistic”philosophy posited that human nature is inherently self-interested and driven by personal gain.In this paper,we explore Han Fei’s keen insights into human nature and its practical application in political governance.His emphasis on aligning political strategies with human inclinations,rather than relying solely on moral preaching,highlights the complexity and pragmatism of his approach.However,we also examine the limitations of his philosophy,particularly in disregarding individual differences and idealism.By striking a balance between political expediency and moral considerations,Han Fei’s ideas continue to resonate with contemporary discussions on governance and human behavior.This study calls for a reflective and cautious assessment of the implications of Han Fei’s“non-moralistic”thought in today’s society. 展开更多
关键词 han Fei non-moralism political primacy principle human nature political governance
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The Kind of Virgin That Keeps a Parrot: Identity, Nature, and Myth in a Painting by Hans Baldung Grien
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作者 Bonnie J. Noble 《Journal of Literature and Art Studies》 2014年第9期702-721,共20页
关键词 鹦鹉 绘画 神话 自然 宗教改革 艺术家 颠覆性 复杂性
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一例Han-Wistar大鼠垂体细胞瘤的病理学分析
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作者 侯敏博 崔甜甜 +5 位作者 苏娜瑛 张苗苗 焦永敏 严建燕 汪溪洁 大平东子 《实验动物与比较医学》 CAS 2023年第6期654-658,共5页
在为期两年的致癌试验中发现空白对照组Han-Wistar大鼠出现1例垂体细胞瘤。临床观察及大体剖检未见明显异常。HE染色结果显示,垂体神经部肿瘤组织呈结节状增生,边界清晰,压迫周围正常组织;肿瘤细胞与神经胶质细胞类似,细胞核呈圆形或卵... 在为期两年的致癌试验中发现空白对照组Han-Wistar大鼠出现1例垂体细胞瘤。临床观察及大体剖检未见明显异常。HE染色结果显示,垂体神经部肿瘤组织呈结节状增生,边界清晰,压迫周围正常组织;肿瘤细胞与神经胶质细胞类似,细胞核呈圆形或卵圆形,细胞质丰富呈嗜酸性或空泡状;肿瘤细胞分化良好,细胞多形性不明显,核分裂象可见;部分肿瘤细胞呈假菊形团状排列。免疫组织化学染色结果显示,胶质纤维酸性蛋白(glial fibrillary acidic protein,GFAP)及S-100蛋白呈阳性。结合HE染色及免疫组织化学染色结果诊断该肿瘤为自发性良性垂体细胞瘤。 展开更多
关键词 垂体细胞瘤 han-Wistar大鼠 病理学诊断
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Carbonatite Occurrence in Ambaji-Sendra Belt of NW Indian Shield: Evidence of Carbonatitic Magmatism in the Subduction Setting
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作者 Sadaf Siddiqui Sadaf Fatima +1 位作者 Tavheed Khan Mohammad Shamim Khan 《International Journal of Geosciences》 CAS 2023年第1期52-74,共23页
The paper represents a new discovery of a late Mesoproterozoic lenticular and discontinuous, carbonatitic body exposed at Basantgarh, Sendra and near the Abu-road area of the Ambaji-Sendra belt of the South Delhi Fold... The paper represents a new discovery of a late Mesoproterozoic lenticular and discontinuous, carbonatitic body exposed at Basantgarh, Sendra and near the Abu-road area of the Ambaji-Sendra belt of the South Delhi Fold Belt. It is medium to coarse-grained and light to dark coloured compact rock. The common associates of the carbonatitic rock are felsic rocks, rich in alkalies. Carbonatite contains more than 50% carbonate minerals, the majority of which are calcite, dolomite, ankerite, augite-aegirine augite and plagioclase. It is classified as calcite carbonatite of the s&#246;vite variety due to its coarse-grained character, chemically as calico-carbonatite and magnesio-carbonatite and even as silico-carbonatites for having more than 20% SiO<sub>2</sub>. The &#8721;REE contents of calico-carbonatite samples are nearly 100 times greater than magnesio-carbonatite. Chondrite normalised REE profiles of calcio-carbonatites are LREE enriched with nearly flat HREEs whereas the magnesio-carbonatite is characterised by flat REE patterns. The mantle-normalized incompatible trace element spidergram of Ambaji-Sendra belt carbonatites shows distinct negative anomalies of Ba, Nb, Ta, P, Sm, Eu, Ti and Y and positive at U and Pb by calcio-carbonatite whereas the magnesio-carbonatite displays negative kinks at K, Zr, Nb, Ta and Ti and positive at Th, Pb and Sr. The variable and/or contrasting enrichment/depletion in various elements in the two types of Ambaji-Sendra belt carbonatite is attributed either to significant differences in the type and modal proportion of different accessory mineral species or selective incorporation of metasomatic fluids during the subduction process. The chemical attributes of Ambaji-Sendra belt carbonatite suggest its emplacement in subduction settings. 展开更多
关键词 Aravalli Craton Ambaji-Sendra Belt Precambrian Carbonatite Subduction Set-ting
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放射性分析中本底对表观计数效率的影响
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作者 冯孝贵 袁建华 +2 位作者 何千舸 王建晨 陈靖 《核化学与放射化学》 CAS CSCD 北大核心 2024年第3期240-245,I0003,共7页
在放射性分析中,尤其对低活度样品,样品本底的影响是必须要考虑的一个因素。分析实践中,常常涉及计数效率和本底(准确说是确定性本底)的概念,但很少提到表观计数效率和随机性本底。本工作在介绍相关概念的基础上,利用Excel“随机数发生... 在放射性分析中,尤其对低活度样品,样品本底的影响是必须要考虑的一个因素。分析实践中,常常涉及计数效率和本底(准确说是确定性本底)的概念,但很少提到表观计数效率和随机性本底。本工作在介绍相关概念的基础上,利用Excel“随机数发生器”研究了本底(包括确定性本底和随机性本底)对表观计数效率的影响规律。本底的影响分为两个方面:一个是因本底扣除不准确而引入的系统误差,它使所有表观计数效率向同一方向偏离计数效率;另一个是本底波动导致的偶然误差,它使表观计数效率在一定范围内随机波动。不管是哪一种误差,本底对表观计数效率的影响均将随着样品活度的降低而增大。对高活度样品,可以不用区分表观计数效率和计数效率这两个概念,但对低活度样品必须区别使用。在有高活度标准源时,不推荐使用通过测量大量低活度样品来获取计数效率的低效方法,宜通过测量活度足够高的标准样品(即本底影响可以忽略的样品)来获取计数效率。 展开更多
关键词 放射性分析 本底 随机性本底 计数效率 表观计数效率
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基于门控卷积生成对抗网络的西汉漆箱纹饰图案数字化修复研究 被引量:1
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作者 周强 王露 +3 位作者 冯金牛 王莹 朱建锋 罗宏杰 《陕西科技大学学报》 北大核心 2024年第1期153-160,共8页
中国历史上漆器以其精美的纹饰技法闻名于世,针对古代漆器表面破损严重、纹饰信息大面积缺失的彩绘漆箱修复难题,提出了一种门控卷积生成对抗网络(GC-GAN)的古代漆箱表面图案修复方法.该方法采用门控卷积结构改进生成对抗网络模型,以提... 中国历史上漆器以其精美的纹饰技法闻名于世,针对古代漆器表面破损严重、纹饰信息大面积缺失的彩绘漆箱修复难题,提出了一种门控卷积生成对抗网络(GC-GAN)的古代漆箱表面图案修复方法.该方法采用门控卷积结构改进生成对抗网络模型,以提升模型对于图像中有效像素的学习能力并解决不规则大面积图像区域的高分辨率修复问题.在此基础上,首先对漆箱图案中的畸变、破损和缺失部分进行掩膜处理,然后使用GC-GAN生成掩膜区域的图案.针对漆箱纹饰图案样本数量少的问题,借助迁移学习思想,将模型在CelebA、SVHN等多种公共数据集上学习到的知识迁移到漆箱纹饰上.最终实现了“西安凤栖原西汉家族墓地”M1墓室中出土的大型木胎彩绘漆箱表面纹饰的数字化虚拟修复. 展开更多
关键词 漆器 西汉漆箱纹饰图案 数字化修复 门控卷积 生成对抗网络
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从汉简看汉代奏议书写形态的法定性与视觉修辞
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作者 韩高年 王敬博 《中国文学研究》 北大核心 2024年第3期42-52,共11页
奏议起源于先秦的朝堂议政,是臣僚向君王谢恩、陈请、议政、进谏的文书。在汉代“以文御国”的背景下,出于行政需要,文质兼备的奏议章表应运勃兴。奏议文书往往“因事而发”,蕴含着非凡的政治智慧,具有政治实用性;其内容、格式、书写等... 奏议起源于先秦的朝堂议政,是臣僚向君王谢恩、陈请、议政、进谏的文书。在汉代“以文御国”的背景下,出于行政需要,文质兼备的奏议章表应运勃兴。奏议文书往往“因事而发”,蕴含着非凡的政治智慧,具有政治实用性;其内容、格式、书写等具有固定的套语格式和鲜明的制度化特征。其文本对特定称谓和程序化语言的运用,表明其书写形态的法定性。传世汉代奏议多出自史书载录,大多曾经史家“裁剪”,“过滤”了其书写形态运用视觉修辞的诸多“细节”,有碍于一窥奏议之“全豹”。借助西北汉简实物,可直观奏议文本特定称谓与程序化语言及其书写借助字体大小、隶草变化、笔划夸饰等书写视觉效果变化,突出奏议文本物化形态的视觉修辞策略,借以强调文本书写与礼制的内在联系。 展开更多
关键词 汉简 汉代奏议 书写形态 视觉修辞策略
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中国人的头面部观察指标特征
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作者 张兴华 郑连斌 +1 位作者 李咏兰 宇克莉 《天津师范大学学报(自然科学版)》 CAS 北大核心 2024年第2期75-80,共6页
对中国53个民族(62个族群)的8项头面部观察指标出现率进行研究,探讨中国人头面部观察指标的特征.结果显示,中国人多有上眼睑皱褶,上唇皮肤部高多中等,多薄唇,鼻翼较宽,三角形耳垂出现率超过20%,凸鼻背出现率低.北亚类型族群的有内眦褶... 对中国53个民族(62个族群)的8项头面部观察指标出现率进行研究,探讨中国人头面部观察指标的特征.结果显示,中国人多有上眼睑皱褶,上唇皮肤部高多中等,多薄唇,鼻翼较宽,三角形耳垂出现率超过20%,凸鼻背出现率低.北亚类型族群的有内眦褶率、凸鼻背、宽鼻翼和薄唇的出现率高于南亚类型族群,上眼睑有皱褶率、眼裂高度狭窄型率、三角形耳垂出现率、上唇皮肤部高中等型率低于南亚类型族群.主成分分析结果表明,中国南亚类型族群的头面部特征比较接近,北亚类型族群的位点明显分散,反映出头面部特征差异较大.汉族族群的位点也比较分散,未形成明显的汉族位点聚集区.中国北亚类型族群、南亚类型族群及汉族族群头面部观察指标的差异多受遗传因素影响. 展开更多
关键词 头面部 观察指标 北亚类型 南亚类型 汉族
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阳关:西汉经敦煌郡与西域间交流交往的关隘——基于史籍与出土文献的考察
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作者 魏迎春 郑炳林 《苏州大学学报(哲学社会科学版)》 北大核心 2024年第1期176-182,共7页
西汉敦煌郡阳关、玉门关的命名与设置布局应是仿照中原关隘布局而来的,即复制或者移植了中原地区的关隘名称与布局。而悬泉汉简所载“敦煌塞”很可能就是指阳关一带的边塞,也即阳关都尉所辖边塞。阳关是西汉中原前往西域地区使用最多的... 西汉敦煌郡阳关、玉门关的命名与设置布局应是仿照中原关隘布局而来的,即复制或者移植了中原地区的关隘名称与布局。而悬泉汉简所载“敦煌塞”很可能就是指阳关一带的边塞,也即阳关都尉所辖边塞。阳关是西汉中原前往西域地区使用最多的关隘。西汉敦煌郡九置组成的邮驿系统向东可通达长安,向西从最西端的龙勒置就近经由阳关出塞,又经文候鄣可抵达鄯善国伊循城,至此连接西域南道。这条阳关通道相对玉门关通道更便于通行,因而,阳关通道是文书传送之路,也是戍卒、施刑士来往之路,还是西汉与西域间通使、通商之路。因此,阳关应当是为了与西域诸国通使通商需要而设置的关隘,此后成为西汉中原与西域交流交往交融的一扇大门。 展开更多
关键词 西汉 阳关 敦煌郡 西域
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我国当代西文编目工作的积极推动者——纪念韩荣宇先生诞辰100周年
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作者 林明 王静 《大学图书馆学报》 北大核心 2024年第2期108-113,共6页
总结了韩荣宇先生在解决图书编目历史遗留问题、推行国际著录标准、开展编目规范工作、恢复完善西文主题目录、培养人才等方面为我国当代西文图书编目工作所作的突出贡献。
关键词 韩荣宇 中国图书馆史 西文编目
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近现代中等师范学校劳动教育课程的演变:历程、特征及启示
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作者 李晓华 胡惠贞 《扬州大学学报(高教研究版)》 2024年第1期63-72,共10页
从清末到民国时期,近现代中等师范学校劳动教育课程在社会变革过程中,受不同教育思潮影响,经历了从“手工科”到“应用工农艺”再到“劳作科”的演变历程。近现代中等师范学校劳动教育课程既紧随着中小学劳动教育的发展步伐而调整,同时... 从清末到民国时期,近现代中等师范学校劳动教育课程在社会变革过程中,受不同教育思潮影响,经历了从“手工科”到“应用工农艺”再到“劳作科”的演变历程。近现代中等师范学校劳动教育课程既紧随着中小学劳动教育的发展步伐而调整,同时又不断呈现出自身内在独有的特征:课程目标由单向度设定走向多向度发展,课程内容由劳动知识与技能的获取转向劳动理论与实践的整合,课程场域由教室转向实地参观考察。思考和总结近现代中等师范学校劳动教育课程演变发展的经验教训,当下师范院校劳动教育课程建设应确立劳动促使人自由全面发展的课程目标,构建知识、技能与情感相统一的课程内容,建立校内外联结的课程场域。 展开更多
关键词 劳动教育 中等师范教育 近现代中国 课程设置
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小尾寒羊不同部位风味物质与风味前体物的相关性分析
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作者 王宇 淑英 +4 位作者 王慧婷 张旭 梁孙硕 焦颖雪 张志胜 《中国食品学报》 EI CAS CSCD 北大核心 2024年第1期263-277,共15页
以6~7月龄、体质量为50 kg的小尾寒羊为实验对象,选取颈肉(NM)、里脊(LLDM)和腿肉(RG),对小尾寒羊挥发性风味物质、脂肪酸和氨基酸进行相关性分析。结果表明:在3个部位共检测到45种挥发性风味物质,其中醛类是最主要的挥发性风味物质,占... 以6~7月龄、体质量为50 kg的小尾寒羊为实验对象,选取颈肉(NM)、里脊(LLDM)和腿肉(RG),对小尾寒羊挥发性风味物质、脂肪酸和氨基酸进行相关性分析。结果表明:在3个部位共检测到45种挥发性风味物质,其中醛类是最主要的挥发性风味物质,占总挥发性风味物质的50%左右。经主成分分析得知,庚醛、壬醛、苯甲醛等24种风味物质是导致不同部位间挥发性风味物质差异的主要影响因素。LLDM中对人体有益的单不饱和脂肪酸和多不饱和脂肪酸含量均为最高,脂肪酸比例更符合人体对羊肉脂肪酸营养价值的需求,对人体健康更有益。氨基酸中以谷氨酸(Glu)和赖氨酸(Lys)为主,约占总氨基酸的17%和10%,其中RG除蛋氨酸(Met)、酪氨酸(Tyr)、赖氨酸(Lys)外含量均为最高,且除谷氨酸(Glu)和脯氨酸(Pro)外与LLDM差异不显著,与NM差异均显著。相关性分析表明,多不饱和脂肪酸与大多数挥发性风味物质呈正相关,且与醛类、醇类和芳香类等挥发性风味物质呈显著正相关,这可能是因为多不饱和脂肪酸极易氧化,在氧化过程中生成醛类、醇类和芳香类等物质。氨基酸与大多数醛类和醇类都呈正相关,这可能是因为氨基酸通过转氨反应等一系列反应,最终生成醛类和醇类等物质。 展开更多
关键词 小尾寒羊 不同部位 挥发性风味物质 脂肪酸 氨基酸 相关性
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