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Comparison of Starch Granule Size Distribution Between Hard and Soft Wheat Cultivars in Eastern China 被引量:9
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作者 LI Wen-yang YAN Su-hui YIN Yah-ping LIYong LIANG Tai-bo GU Feng DAI Zhong-min WANG Zhen-lin 《Agricultural Sciences in China》 CAS CSCD 2008年第8期907-914,共8页
Granule size distribution of wheat starch is an important characteristic that can affect its chemical composition and functionality. Two types of wheat cultivars, the hard and soft wheat cultivars, grown at Tai'an Ex... Granule size distribution of wheat starch is an important characteristic that can affect its chemical composition and functionality. Two types of wheat cultivars, the hard and soft wheat cultivars, grown at Tai'an Experimental Station of Shandong Agricultural University, Taian, Shandong, China, were examined in this study. The granule size distribution and amylose contents in wheat grains were studied and compared, and relationships between the properties were identified. A clear bimodal distribution of granule size was shown in all wheat cultivars. Volume distribution of starch granules shows the typical bimodal with peak values in the ranges of 5.6-6.1μm and 20.7-24.9μm, respectively. Also, granule surface area distribution was bimodal with peak values in the ranges of 2.4-3.2μm and 20.7-24.9μm, respectively. Number distribution of granules was a typical population with a peak value in the range of 0.54-1.05μm. Contributions from the granules 〈 2.8μm and 〈 9.9μm to the total volume were in the ranges of 94.2-95.1% and 99.7-99.9% of total number, respectively. Proportions of granules〈2.8μm, 2.8-9.9μm, 9.9-22.8μm, and 22.8-42.8μm were in the ranges of 12.9-14.3%, 28.4-31.1%, 33.5-35.6%, and 19.7-22.7% for hard wheat, and 10.3-13.9%, 26.6-28.1%, 32.7-34.6%, and 24.2-27% for soft wheat. Hard wheat had greater B-type granules ( 〈 9.9μm), and had fewer granules of 22.8-42.8μm than soft wheat. Amylose content was positively related to volume percentage of granules 22.8-42.8μm, and negatively related to volume percentage of granules 2.8-22.8μm. 展开更多
关键词 wheat (Triticum aestivum L.) starch granule size distribution AMYLOSE hard wheat soft wheat
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Magnetic Properties Hard-Soft SmCo<sub>5</sub>-FeNi and SmCo<sub>5</sub>-FeCo Composites Prepared by Electroless Coating Technique 被引量:3
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作者 M. Lamichanne B. K. Rai +2 位作者 S. R. Mishra V. V. Nguyen J. P. Liu 《Open Journal of Composite Materials》 2012年第4期119-124,共6页
Composites of SmCo5-FeNi and SmCo5-FeCo, hard-soft magnetic materials, have been synthesized via electroless plating of magnetically hard SmCo5 powder particles with magnetically soft FeNi and FeCo, respectively. The ... Composites of SmCo5-FeNi and SmCo5-FeCo, hard-soft magnetic materials, have been synthesized via electroless plating of magnetically hard SmCo5 powder particles with magnetically soft FeNi and FeCo, respectively. The influence of coating thickness of soft magnetic layers on the structure and magnetic properties of the composite has been studied. Overall FeNi coating was found to be less dense compared to FeCo for the same plating duration. Structurally the coat ing was found to be nodular in morphology. These coating have dramatic effect on the overall magnetic property of the composite. As compared to FeNi coated SmCo5 composite, two-fold increase in the saturation magnetization has been observed upon coating SmCo5 (Ms^28 emu/g) with FeCo to a value 56 emu/g. The coercivity of composite powder was found to decrease with increasing the coating layer thickness. The absence of exchange spring behavior in the hard-soft composite is attributed to magnetically soft layer thickness exceeding the theoretical length limit for exchange-spring coupling. 展开更多
关键词 ELECTROLESS Plating hard-soft COMPOSITES Exchange Spring
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Constitutive model for methane desorption and diffusion based on pore structure differences between soft and hard coal 被引量:9
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作者 Liu Yanwei Wang Dandan +2 位作者 Hao Fuchang Liu Mingju Mitri Hani S. 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第6期937-944,共8页
This paper aims to improve the accuracy and applicability of gas diffusion mathematical models from coal particles. Firstly, a new constitutive model for gas diffusion from coal particles with tri-disperse pore struct... This paper aims to improve the accuracy and applicability of gas diffusion mathematical models from coal particles. Firstly, a new constitutive model for gas diffusion from coal particles with tri-disperse pore structure is constructed by considering the difference in characteristics between soft coal and hard coal.The analytical solution is then derived, that is, the quantitative relationship between gas diffusion rate(Qt/Q_∞) and diffusion time(t), The pore structure parameters of soft coal and hard coal from Juji coal mine are determined. Gas diffusion rules are numerically calculated and investigated by physical simulation methods. Lastly, the applicability of this model is verified. The results show that the homogeneous model only applies to the gas diffusion process of hard coal during the initial 10 min. The calculation results from this model and the physical experimental results of soft coal and hard coal are nearly identical during the initial 30 min. 展开更多
关键词 soft and hard coal Gas diffusion PORE structure CONSTITUTIVE models Physical simulation
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Influence of confining stress on fracture characteristics and cutting efficiency of TBM cutters conducted on soft and hard rock 被引量:2
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作者 刘京铄 曹平 +1 位作者 刘杰 蒋喆 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第5期1947-1955,共9页
Combined with numerical simulation, the influence of confining stress on cutting process, fracture conditions and cutting efficiencies of soft and hard rock has been conducted on the triaxial testing machine(TRW-3000)... Combined with numerical simulation, the influence of confining stress on cutting process, fracture conditions and cutting efficiencies of soft and hard rock has been conducted on the triaxial testing machine(TRW-3000) designed and manufactured in Central South University(China). Results are obtained by performing analysis on the fracture scopes of cement and granite plates,the characteristics of cutting force in cutting processes and the cutting efficiency. Firstly, the increase of latitude fracture scope and the decrease of longitude fracture scope are both more notable in the tests conducted on cement plates subjected to the increasing confining stresses; secondly, the increase tendency of peak penetration forces obtained from tests conducted on granite plates is more obvious, however, the increase tendencies of average penetration forces achieved from cement and granite plates are close to each other; thirdly, the cutting efficiency could be improved by increasing the spacing between cutters when the confining stress which acts on soft and hard rock increases in a certain degree, and the cutting efficiency of soft rock is more sensitive to the varying confining stresses. 展开更多
关键词 triaxial testing machine numerical study tunnel boring machine(TBM) cutter confining stress soft and hard rock cutting efficiency
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Contrastive Study of Metadiscourse in the Conclusion of Academic Papers between Soft Science and Hard Science
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作者 徐伟伟 《海外英语》 2014年第3X期209-210,共2页
Academic paper as a genre is communicative.Interactional metadiscourse is one of the linguistic features that can significantly show the communicative feature of texts.With different research methodologies and charact... Academic paper as a genre is communicative.Interactional metadiscourse is one of the linguistic features that can significantly show the communicative feature of texts.With different research methodologies and characteristics,academic papers of hard and soft science present different degree of communicative features.The corpus of this study consists of 16 academic papers among which 8 are from hard science and 8 from soft science.This article aims to explore the different ways of scholars from soft and hard science to use metadiscourse in the conclusion part of their academic papers to exert lights to the pedagogical development of academic papers. 展开更多
关键词 academic papers BETWEEN soft SCIENCE and hard scie
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Proximal Femoral Cortical Thickness and Medullary Canal Diameter in Soft and Hard Water Regions
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作者 Ahmed Elmorsy Sarah Whitehouse +1 位作者 John Timperley Stephen Veitch 《Open Journal of Orthopedics》 2016年第3期58-62,共5页
This study compared proximal femoral morphology in patients living in soft and hard water regions. The proximal femoral morphology of two groups of 70 patients living in hard and soft water regions with a mean age of ... This study compared proximal femoral morphology in patients living in soft and hard water regions. The proximal femoral morphology of two groups of 70 patients living in hard and soft water regions with a mean age of 72.29 (range: 50 to 87 years) was measured using an antero-posterior radiograph of the non-operated hip with magnification adjusted. The medullary canal diameter at the level of the lesser trochanter (LT) was significantly wider in patients living in the hard water region (mean width: 1.9 mm wider;p = 0.003). No statistical significant difference was found in the medullary canal width at 10 cm below the level of LT, Dorr index, or Canal Bone Ratio (CBR). In conclusion, the proximal femoral morphology does differ in patients living in soft and hard water areas. These results may have an important clinical bearing in patients undergoing total hip replacement surgery. Further research is needed to determine whether implant survivorship is affected in patients living in hard and soft water regions. 展开更多
关键词 Hip hard Water soft Water Femoral Cortical Thickening Medullary Diameter
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XPS STUDIES OF IRRADIATED HARD AND SOFT Si—SiO_2
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作者 刘昶时 赵元富 +3 位作者 王忠燕 陈萦 刘芬 赵汝权 《Nuclear Science and Techniques》 SCIE CAS CSCD 1993年第3期181-185,共5页
The interracial structure of hard and soft oxides grown by dry oxidation on<100> n-type silicon substrates is examined using high resolution mild X-ray photoelectron spectroscopy (XPS) before and after irradiati... The interracial structure of hard and soft oxides grown by dry oxidation on<100> n-type silicon substrates is examined using high resolution mild X-ray photoelectron spectroscopy (XPS) before and after irradiation. Substantial differences in silicon of silica state (B.E. 103.4 eV), silicon of transitional state (B.E. 101.5 eV), surplus oxygen (B.E. 529.6 eV) and negative two-valence oxygen (B.E. 531.4 eV) are observed between the two kinds of samples. The XPS spectra strongly depend on the conditions of irradiation for soft samples, but do not as remarkablely as soft samples for hard samples. The effects of irradiation doses on XPS are greater than that of irradiation bias fields. Some viewpoints of irradiation induced hole electron pair are proposed to explain the results. 展开更多
关键词 XPS Radiation hard Radiation soft Si-SiO_2 Bias field Radiation dose
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Proteomic analysis reveals the differential proteins of endosperm between soft and hard wheat varieties
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作者 Feng Jia Haicheng Yin +2 位作者 Qi Wang Yu Chen Jinshui Wang 《Grain & Oil Science and Technology》 2019年第2期27-32,共6页
In this study,we revealed the differential proteins from the wheat endosperms using proteomic analysis and investigated their surface properties.The pattern of the polypeptides obtained from the Yangmai-15 and Yangmai... In this study,we revealed the differential proteins from the wheat endosperms using proteomic analysis and investigated their surface properties.The pattern of the polypeptides obtained from the Yangmai-15 and Yangmai-16 wheat varieties were compared using two-dimensional polyacrylamide gels.In addition,we compared the characteristics of the grain such as grain hardness,protein content,wet gluten,dough development time,dough stability,gliadin and glutenin contents between Yangmai-15 and Yangmai-16,and the results were significantly different.Notably,216 and 197 protein spots were separated from Yangmai-15 and Yangmai-16,respectively.The isoelectric points of the identified proteins ranged from 4 to 10 and the molecular weights of proteins varied from 10 to 100 kDa.Further,21 and 8 specific differential protein spots were identified fromthe flour of Yangmai-15 and Yangmai-16,respectively.The surface properties of identified peptides consisted of hydrophobic or hydrophilic residues,as well as randomly scattered residues.The proteomic analysis of the wheat endosperms provides a novel insight into the biochemical basis for the differences in physicochemical properties between the soft and hard wheat varieties. 展开更多
关键词 soft and hard wheat PROTEOME PEPTIDES surfaces ENDOSPERM proteins
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基于物理约束机器学习的PDC钻头智能选型技术研究
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作者 李昌盛 孙华凯 张乐 《钻采工艺》 北大核心 2026年第1期133-140,共8页
为解決传统PDC钻头选型依赖经验、在软硬交错地层中适配性差导致机械钻速低、进尺短等问题,提出一种基于物理约束机器学习的PDC钻头智能选型技术。通过收集7个油田3410口井的23171条钻头使用记录,构建涵盖地层抗钻特性参数(抗压强度、... 为解決传统PDC钻头选型依赖经验、在软硬交错地层中适配性差导致机械钻速低、进尺短等问题,提出一种基于物理约束机器学习的PDC钻头智能选型技术。通过收集7个油田3410口井的23171条钻头使用记录,构建涵盖地层抗钻特性参数(抗压强度、研磨指数、冲击指数)、钻头结构参数、钻井参数及螺杆参数的数据库;基于地层与钻头的适配机理,建立以三参数为核心的物理规则模型,量化刀翼数、切削齿尺寸等结构参数与抗钻特性的匹配关系;将物理规则作为约束嵌入多目标神经网络模型,以机械钻速和进尺为优化目标,结合改进的NSGA-Ⅱ算法搜索帕累托最优解,实现钻头结构参数的定量化自动推荐。现场应用于XQ1井须家河组地层,推荐的6刀翼16 mm齿PDC钻头实现进尺257 m,机械钻速1.69 m/h,较邻井机械钻速提升显著,验证了该技术的科学性与有效性。研究成果为复杂地层PDC钻头高效选型提供了理论与技术支撑。 展开更多
关键词 PDC钻头 物理约束 机器学习 智能选型 软硬交错地层 多目标优化
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数字时代技术工人技能需求变化与岗位薪资:来自中国招聘文本的证据(2014-2024)
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作者 林柏 王禹睿 《晋阳学刊》 2026年第1期104-113,共10页
数字经济背景下,企业对技术工人技能的需求正在经历从单一操作型向复合协同型的再塑。基于2014-2024年全国招聘信息,构建技术工人软、硬技能词典,并对岗位描述开展量化测度,得到岗位层面的技能得分与对数月薪指标,进而检验企业对技术工... 数字经济背景下,企业对技术工人技能的需求正在经历从单一操作型向复合协同型的再塑。基于2014-2024年全国招聘信息,构建技术工人软、硬技能词典,并对岗位描述开展量化测度,得到岗位层面的技能得分与对数月薪指标,进而检验企业对技术工人技能需求结构变动与技术工人岗位薪资的关系,并考察行业与地区异质性。研究发现,在对技术工人的技能需求中,软技能与硬技能均显著提升岗位薪资,且自2020年起软技能的重要性上升更为明显(稳健于更强控制与截尾处理)。行业维度上,软技能在建筑工程等强调沟通协作与现场协调的岗位上回报更突出,硬技能在机械制造与设备维护等技术密集型岗位上更具稳定优势。区域维度上,东部地区对硬技能的回报更高,中西部地区对软技能的回报更显著。上述发现说明,在数字化与组织柔性化并进的环境中,岗位薪资的定价机制正在由单一技能溢价转向“软硬并重”的综合能力溢价。 展开更多
关键词 数字经济 技术工人 技能结构 软技能/硬技能 岗位薪资
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High energy product of isotropic bulk Sm-Co/α-Fe(Co)nanocomposite magnet with multiple hard phases and nanoscale grains 被引量:6
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作者 Shuo Li Longfei Ma +5 位作者 Jinkui Fan Jianping Yang Qiang Zheng Baoru Bian Jian Zhang Juan Du 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第29期183-188,共6页
Nanocomposite magnets consisting of hard and soft magnetic phases have potential applications to be the next generation of permanent magnets with very high energy product and less expensive rare-earth elements.But it ... Nanocomposite magnets consisting of hard and soft magnetic phases have potential applications to be the next generation of permanent magnets with very high energy product and less expensive rare-earth elements.But it is still a big challenge to obtain bulk magnets with ideal microstructure and high performance.In this work,two-step warm processing at relative low temperatures had been adopted to obtain nearly theoretical density bulk nanocomposite magnets from amorphous/nanocrystalline powder precursors.Novel nanostructures consisting of multiple Sm-Co hard phases(SmCo_(5)as main phase,SmCO_(3),SmCo_(7),Sm_(2)Co_(17)as minor phases)and 25 wt%α-Fe(Co)soft phase,nanoscale grain size below 20 nm for both the hard phase and soft phase,and the diffusion of Fe and Co compositions had been obtained in bulk isotropic magnets.Besides the ideal nanostructures,a high coercivity of 5.9 kOe,M_(r)/M_(s)value of 0.78 and a high square degree of demagnetization curve S=0.47 were obtained.All of these factors together brought a new record-high energy product(BH)_(max)of 23.6 MGOe.These results make an important step toward fabricating novel nanostructure with high performance. 展开更多
关键词 hard/soft phase nanocomposite Isotropic bulk Magnetic properties Grain size Phase constitution
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用于输送带修补胶的室温固化聚氨酯的制备与性能研究
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作者 赵彤 冯桐伟 +3 位作者 孟阳 赵成哲 于冰 田明 《高分子学报》 北大核心 2026年第1期157-167,共11页
橡胶输送带常受到磨损而影响正常使用,通常使用浇注型聚氨酯等材料作为修补胶对磨损处进行现场修补,但现有聚氨酯修补胶对橡胶的粘接强度难以满足实际需求,且浇注型聚氨酯的结构组成与粘接强度间关系的研究尚不完善.基于此,本工作利用... 橡胶输送带常受到磨损而影响正常使用,通常使用浇注型聚氨酯等材料作为修补胶对磨损处进行现场修补,但现有聚氨酯修补胶对橡胶的粘接强度难以满足实际需求,且浇注型聚氨酯的结构组成与粘接强度间关系的研究尚不完善.基于此,本工作利用预聚体法成功制备了可室温固化的聚氨酯涂层,并同时从分子内聚力、润湿能力、粘接界面微观结构等角度对涂层与橡胶间的粘接性能展开研究.研究结果显示:硬段含量越高,分子内聚力越强,浇注型聚氨酯固化后形成的涂层对橡胶基体越容易形成更好的附着,T型剥离强度最高可达11.73 N/mm;低黏度浇注型聚氨酯有利于形成良好附着,适合的附着层厚度是良好粘接的关键.除此之外,本工作还研究了软硬段含量对浇注型聚氨酯涂层的拉伸性能、耐磨性能及硬度的影响,为浇注型聚氨酯涂层的制备与性能调控提供了理论支持.该聚氨酯涂层预期可作为橡胶修补胶,实现对橡胶输送带的室温快速修补. 展开更多
关键词 浇注型聚氨酯 室温固化 软硬段含量 黏度 内聚力
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“双碳”目标的法治化实现——法律的综合之治与协同共治
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作者 杨解君 李剑 《湖南工业大学学报(社会科学版)》 2026年第1期95-103,共9页
实现“双碳”目标,必须以法治化思维和方式推进。在法律规范层面,“硬法”规范和“软法”规范皆不可或缺,需要二者兼备。在部门法层面,需要多个法律部门的协同共治,尤其应发挥环境法、能源法、技术法、经济法、涉外法和行政法的综合治... 实现“双碳”目标,必须以法治化思维和方式推进。在法律规范层面,“硬法”规范和“软法”规范皆不可或缺,需要二者兼备。在部门法层面,需要多个法律部门的协同共治,尤其应发挥环境法、能源法、技术法、经济法、涉外法和行政法的综合治理作用。 展开更多
关键词 “双碳”目标 法治化 “硬法” “软法” 协同共治
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图书馆发展的软服务约束
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作者 魏辅轶 李媛 《四川图书馆学报》 2026年第1期74-79,共6页
文章从预算模式的角度解释图书馆服务发展迟滞的原因。通过引入经济学中软预算约束的概念,讨论图书馆预算的经济属性,指出图书馆属于软预算约束下的组织机构。进一步提出了“软服务约束”的概念来解释图书馆运行中出现的组织行为异化的... 文章从预算模式的角度解释图书馆服务发展迟滞的原因。通过引入经济学中软预算约束的概念,讨论图书馆预算的经济属性,指出图书馆属于软预算约束下的组织机构。进一步提出了“软服务约束”的概念来解释图书馆运行中出现的组织行为异化的五种特征,并提出图书馆服务发展的迟滞是在软服务约束下,读者、图书馆、馆员三者发展目标不能统一的结果。再进一步,解释了软服务约束不能完全消除的根本原因在于软预算约束的影响,但可以通过图书馆资本多元化和“馆人同评”的新评价体系来尽量消除软服务约束的影响。 展开更多
关键词 图书馆 软预算约束 硬预算约束 图书馆服务 服务评价
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某抽水蓄能电站软硬岩掺合料碾压试验
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作者 郭传科 李蒋金 高昱芃 《水电能源科学》 北大核心 2026年第1期99-103,共5页
近年来,抽水蓄能电站快速发展,建设过程中经常面临软硬岩混合利用的问题。软岩岩性较差,在施工过程中存在明显破碎现象,软硬岩混合料是否能满足筑坝强度和渗透特性的要求值得进一步探究。对安徽某拟建抽水蓄能电站的软硬岩筑坝料开展现... 近年来,抽水蓄能电站快速发展,建设过程中经常面临软硬岩混合利用的问题。软岩岩性较差,在施工过程中存在明显破碎现象,软硬岩混合料是否能满足筑坝强度和渗透特性的要求值得进一步探究。对安徽某拟建抽水蓄能电站的软硬岩筑坝料开展现场碾压试验,研究其在不同碾压参数条件下的物理力学和渗透特性。设计了全面的试验方案,比较了不同碾重(22、26 t)、加水量(5%、10%)、铺层厚度(0.6、0.8 m)和碾压遍数(6、8、10遍)组合条件下的碾压效果。采用新型张拉式直剪试验方法现场测定碾压后堆石料的抗剪强度指标,给出了满足设计要求的碾压参数,弥补了室内试验与现场工况的差异,为坝坡稳定性复核提供了直接依据。研究表明,相同碾压参数条件下,掺50%含碳质的绢云千枚岩混合料的干密度、渗透系数、抗剪强度均比绢云千枚岩混合料略小;混合料干密度随碾压遍数增加而增大,并呈现收敛趋势;提高碾重与减小铺层厚度均能显著提升压实质量。在颗粒破碎特性方面,碾压过程中颗粒破碎主要发生在铺层表层,而深层位置的堆石料由于细颗粒的包裹作用基本不发生破碎。绢云千枚岩混合料主要为大颗粒破碎,而含碳质绢云千枚岩混合料在碾压表层发生多次破碎,碾后呈粉质。在铺层厚度80 cm条件下,22 t振动碾碾压10遍得到的强度参数与26 t振动碾碾压8遍的强度参数基本相同。基于试验结果并综合考虑现场施工质量和效率,建议对绢云千枚岩混合料采用铺料层厚80 cm、加水量10%,各铺层采用22 t碾重振动碾压10遍,或采用26 t碾重振动碾压8遍的施工参数。 展开更多
关键词 软硬岩掺合料 碾压试验 碾压控制参数 抽水蓄能电站
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基于双体系建设的中国航空国际物流供应链优化研究
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作者 王勇 刘震 许秀峰 《中国商论》 2026年第1期114-118,共5页
在以国内大循环为主体、国内国际双循环相互促进的新发展格局下,全球物流供应链体系进入新一轮震荡和重组阶段。高端物流领域的国际航空物流具备时效高、跨度大、聚集效应强等显著优势,企业参与重构国际航空物流供应链迎来重大机遇。本... 在以国内大循环为主体、国内国际双循环相互促进的新发展格局下,全球物流供应链体系进入新一轮震荡和重组阶段。高端物流领域的国际航空物流具备时效高、跨度大、聚集效应强等显著优势,企业参与重构国际航空物流供应链迎来重大机遇。本文通过分析中国国际航空物流供应链体系建设的背景发现,中国国际航空物流供应链企业不仅可以通过推动国际航权开放、布局国际物流枢纽、引进全货机和丰富国际航线网络等措施打造国际航空物流供应链的硬体系,还可以通过构建新型“航空物流+跨境电商”国际供应链、推进数字化赋能和完善航空物流供应链纵向一体化结构等措施打造国际航空物流供应链的软体系,进而探索基于双体系建设的中国航空国际物流供应链优化实践路径。 展开更多
关键词 国际航空 供应链 双循环 软体系 硬体系
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根盾技术在前牙美学区即刻种植中的应用进展
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作者 罗嘉童 杨佳康 王柏翔 《口腔医学》 2026年第1期76-80,共5页
前牙区修复存在的美学问题一直受到广泛关注,牙齿拔除后唇侧牙槽骨的吸收可导致轮廓塌陷。即刻种植术虽然能一定程度上减少骨吸收量,但不能达到理想的美学效果。根盾技术是指通过保留患牙唇侧一定厚度和形态的健康牙根片,形成牙根-牙周... 前牙区修复存在的美学问题一直受到广泛关注,牙齿拔除后唇侧牙槽骨的吸收可导致轮廓塌陷。即刻种植术虽然能一定程度上减少骨吸收量,但不能达到理想的美学效果。根盾技术是指通过保留患牙唇侧一定厚度和形态的健康牙根片,形成牙根-牙周膜-牙槽骨复合体,以维持牙槽嵴厚度、防止牙槽嵴吸收的一种技术。本综述就根盾技术的分类、临床要点、并发症的处理等方面进行回顾,旨在为临床医师在美学区种植修复中合理应用该技术提供参考依据。 展开更多
关键词 根盾技术 即刻种植 软硬组织保存
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成人与青少年骨性Ⅲ类错[牙合]畸形患者掩饰性治疗后软硬组织和牙周情况对比分析
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作者 武孝芬 张延晓 +2 位作者 徐庆 罗远 孙晗 《中国美容医学》 2026年第3期132-138,共7页
目的:对成人与青少年骨性Ⅲ类错[牙合]畸形患者进行正畸掩饰性治疗,对比治疗前后软硬组织侧貌及牙周支持组织的变化,评价不同年龄组正畸治疗效果的差异。方法:选取2020年7月-2023年6月于无锡口腔医院就诊的40例符合研究标准的骨性Ⅲ类错... 目的:对成人与青少年骨性Ⅲ类错[牙合]畸形患者进行正畸掩饰性治疗,对比治疗前后软硬组织侧貌及牙周支持组织的变化,评价不同年龄组正畸治疗效果的差异。方法:选取2020年7月-2023年6月于无锡口腔医院就诊的40例符合研究标准的骨性Ⅲ类错[牙合]畸形患者,其中成年组20例,青少年组20例。两组均采取Damon Q自锁托槽矫治技术,期间未采用微种植体、前牵引面具等额外支抗装置,比较两组治疗前后软硬组织、牙周支持组织的测量值,评价不同年龄组的治疗效果及差异。结果:①治疗后,成年组患者硬组织NA-APo以及ANB角增大、AB-NPo、OP-FH、L1-MP、FMIA、IMPA角减小,软组织Si-H、A-NPog、H-N'Pm'增加;青少年组硬组织AB-NPo角减小,SNA、ANB角增大,FMIA增大,L1-OP、IMPA角度均减小,软组织Si-H增加,Ss-Ls、Li-H、FA(U1)-Ls减小,以上差异均有统计学意义(P<0.05);组间差异除SNA外,其余无统计学意义;②治疗后,牙周变化量中成年组PLI、PD、BC-CP较治疗前增加,青少年组PLI增加,而31、42牙位PD、BC-CP测量值较治疗前减小,治疗前后及组间比较差异有统计学意义(P<0.05)。结论:正畸掩饰性治疗可以通过下前牙舌倾及上前牙唇倾,解决前牙反[牙合],对改善轻中度骨性Ⅲ类错[牙合]畸形患者上下颌骨发育不调有一定促进作用,无论成年还是青少年患者,患者的Ⅲ类骨面型均得到有效改善。且青少年患者随着前牙反[牙合]的解除,上颌发育不足改善,下前牙牙周支持组织改建,牙周情况改善。 展开更多
关键词 骨性Ⅲ类错[牙合]畸形 正畸 掩饰性治疗 软硬组织 牙周状况 成人 青少年
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盾构隧道穿越上软下硬地层地表变形数值模拟研究
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作者 张红彬 王跃翔 +3 位作者 夏琴 熊峰 王朋朋 匡星晨 《合肥工业大学学报(自然科学版)》 北大核心 2026年第1期127-132,共6页
盾构隧道在上软下硬地层掘进时,由于掌子面地层物理力学性质复杂,易引起地面沉降或隆起。文章以芜湖城南过江隧道为工程背景,探讨隧道穿越上软下硬地层时地表变形规律。运用FLAC3D软件对典型上软下硬地层区间施工过程进行数值模拟,结合... 盾构隧道在上软下硬地层掘进时,由于掌子面地层物理力学性质复杂,易引起地面沉降或隆起。文章以芜湖城南过江隧道为工程背景,探讨隧道穿越上软下硬地层时地表变形规律。运用FLAC3D软件对典型上软下硬地层区间施工过程进行数值模拟,结合现场监测数据,分析隧道埋深、掌子面砂层与岩层厚度比、掌子面附加压力对地表变形影响。结果表明:砂层中地表沉降与隧道埋深呈正相关;复合地层中地表沉降与开挖面砂层厚度占比呈正相关;开挖面附加压力存在最适区间,超过最适区间都会引起地层变形增大。该研究结果可为上软下硬地层中隧道施工提供指导。 展开更多
关键词 盾构隧道 上软下硬地层 地表沉降 数值模拟 掌子面附加压力
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上软下硬地层大跨地铁车站初支拱盖法开挖力学特性研究
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作者 刘正 《国防交通工程与技术》 2026年第1期77-81,共5页
为研究上软下硬地层初支拱盖法力学特性,以锦江路站为例,选取车站中部典型断面作为分析对象,对不同施工阶段进行了初期支护、临时支护及大拱盖结构的应力分析和拱顶及地表沉降监测。研究结果表明:在各分析工况下,初期支护与临时支护的... 为研究上软下硬地层初支拱盖法力学特性,以锦江路站为例,选取车站中部典型断面作为分析对象,对不同施工阶段进行了初期支护、临时支护及大拱盖结构的应力分析和拱顶及地表沉降监测。研究结果表明:在各分析工况下,初期支护与临时支护的最大主拉应力和最大主压应力均远小于C25喷射混凝土的抗拉强度设计值和抗压强度设计值,支护结构整体处于安全状态。沉降监测显示:最大拱顶沉降、最大地表沉降,均满足规范控制要求;沉降主要发生在上部导坑开挖阶段,大拱盖施作后沉降趋于稳定,并有效减小了下部开挖引起的附加变形。采用初支拱盖法对保证施工安全、控制变形和加快施工进度起到了关键作用。 展开更多
关键词 上软下硬地层 初支拱盖法 地表沉降 结构受力 临时支护
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