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Comparison of Starch Granule Size Distribution Between Hard and Soft Wheat Cultivars in Eastern China 被引量:7
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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:8
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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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Mixed-Weights Least-Squares Stable Predictive Control Algorithm with Soft and Hard Constraints 被引量:3
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作者 周立芳 邵之江 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第5期565-570,共6页
Mixed-weight least-squares (MWLS) predictive control algorithm, compared with quadratic programming (QP) method, has the advantages of reducing the computer burden, quick calculation speed and dealing with the case in... Mixed-weight least-squares (MWLS) predictive control algorithm, compared with quadratic programming (QP) method, has the advantages of reducing the computer burden, quick calculation speed and dealing with the case in which the optimization is infeasible. But it can only deal with soft constraints. In order to deal with hard constraints and guarantee feasibility, an improved algorithm is proposed by recalculating the setpoint according to the hard constraints before calculating the manipulated variable and MWLS algorithm is used to satisfy the requirement of soft constraints for the system with the input constraints and output constraints. The algorithm can not only guarantee stability of the system and zero steady state error, but also satisfy the hard constraints of input and output variables. The simulation results show the improved algorithm is feasible and effective. 展开更多
关键词 软约束条件 硬约束条件 混合权系数 最小二乘法 稳定性 预测控制 算法 可行性 工业控制 自动控制系统
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Numerical simulation for rheological characteristics of alternating distribution of soft and hard rock layers 被引量:1
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作者 韩冰 王芝银 +1 位作者 丁秀丽 徐平 《Journal of Coal Science & Engineering(China)》 2006年第1期1-5,共5页
The difficulty of selecting appropriate rheological model and parameters for the alternating distribution of soft and hard rock layers was often encountered due to the unhomogeneity, discontinuity and anisotropy of ro... The difficulty of selecting appropriate rheological model and parameters for the alternating distribution of soft and hard rock layers was often encountered due to the unhomogeneity, discontinuity and anisotropy of rock mass. The Burgers and generalized Kelvin models were applied to the soft and hard rock respectively and the rheological parameters were obtained based on the method of optimum separation. By using the simulated code FLAC^(3D), the stability of surrounding rocks of a certain underground plant was analyzed. The effect of surface load and weakening the parameters intensity of argillaceous and bioclastic interlayers between soft and hard rock on rheological behavior of layer composite rock mass was investigated. The results indicate that the rheological characteristics of soft and hard rock layer in composite rock mass can be described well with above two rheological models. 展开更多
关键词 流变学 数值模拟 软岩层 硬岩层 交互分布
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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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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 irradiation. ... 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-SiO2 Bias field RADIATION dose
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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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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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Substitution or Complementarity Between "Soft" Information and "Hard" Information: Why and Which Effect on Bank Profitability?
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作者 Herve Alexandre Aymen Smondel 《Journal of Modern Accounting and Auditing》 2012年第6期785-826,共42页
关键词 风险信息 银行业 互补 盈利 SMES 决策过程 信息成本 委员会
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结合型式对地铁车站上盖物业的振动响应影响
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作者 许炜萍 刘易然 +5 位作者 黄谦 刘旭 赵楚轩 王呼佳 杨朋 孙克国 《西南交通大学学报》 EI CSCD 北大核心 2024年第3期653-662,共10页
为研究地铁振动对不同结合类型地铁车站及其上方的动力反应影响,基于地铁车站与上盖物业连接型式的主要承载区别,提出“软结合”“硬结合Ⅰ”“硬结合Ⅱ”3种结合型式;然后,采用车-轨耦合模型得到列车荷载谱,利用有限差分软件FLAC^(3D)... 为研究地铁振动对不同结合类型地铁车站及其上方的动力反应影响,基于地铁车站与上盖物业连接型式的主要承载区别,提出“软结合”“硬结合Ⅰ”“硬结合Ⅱ”3种结合型式;然后,采用车-轨耦合模型得到列车荷载谱,利用有限差分软件FLAC^(3D)建立地铁车站-上盖物业数值仿真模型,并与实测数据进行对比,验证数值仿真模型与参数的正确性;最后,基于数值仿真,从时域、频域出发,研究3种结合型式下上盖物业的振动响应.研究结果表明:软结合型式下站厅层到上盖物业一层加速度峰值减小69.10%,硬结合Ⅰ型减小2.08%,硬结合Ⅱ型增大2.94%,硬结合型式下上盖物业振动加速度较软结合型式大;3种结合型式下上盖物业振动的频率主要在40~90 Hz,且对于上盖物业同一楼层,振动随距振源距离的增大而逐渐减小;软结合型式下上盖物业一层加速度级最大值为68.2 dB,较站厅层减小11.3 dB;硬结合Ⅰ型、硬结合Ⅱ型的上盖物业加速度级最大值分别为83.4、79.4 dB;地铁振动造成上盖物业附加第一主应力很小,且在向上传播过程中衰减很快;从站厅层到上盖物业,软结合型式第一主应力衰减85.81%,硬结合Ⅰ、Ⅱ型式分别衰减63.46%、72.27%,间隔土对附加应力有明显衰减作用.在地铁实际建设工程中建议选用软结合型式. 展开更多
关键词 地铁车站 上盖物业 列车荷载 软结合 硬结合 振动响应
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煤层瓦斯含量测定技术及装备研究进展 被引量:1
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作者 孙四清 杨帆 +1 位作者 郑玉岐 张庆利 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第4期164-176,共13页
瓦斯含量是煤与瓦斯突出危险预测、煤层瓦斯资源量估算、矿井瓦斯治理工程设计的重要参数。围绕如何在大区域准确快速测定煤层瓦斯含量,依托国家科技重大专项、国家自然科学基金和煤炭企业联合基金等项目科技攻关,在取样、测试方面取得... 瓦斯含量是煤与瓦斯突出危险预测、煤层瓦斯资源量估算、矿井瓦斯治理工程设计的重要参数。围绕如何在大区域准确快速测定煤层瓦斯含量,依托国家科技重大专项、国家自然科学基金和煤炭企业联合基金等项目科技攻关,在取样、测试方面取得了一定进展。主要表现在如下4个方面:①煤层瓦斯含量测定取样经历了孔口接样、岩心管定点取样、压力引射定点取样和密闭取样4个阶段,密闭取样装备保压能力达到11.5 MPa,煤心直径达到38 mm;②针对不同煤层地质条件,发展形成了顺煤层定向长钻孔密闭取样、底板穿层钻孔密闭取样和顶(底)板梳状定向长钻孔密闭取样3种取样技术;③在河南焦作和山西晋城矿区硬煤层中,顺层定向长钻孔取样深度达到516 m,密闭取样法测得煤层瓦斯含量较常规取样法分别平均提高了0.44倍和1.04倍。在安徽淮南矿区碎软煤层中,穿层钻孔密闭取样深度达到209 m,测得煤层瓦斯含量较常规取样法平均提高了0.26倍;在安徽淮北矿区碎软煤层中,顶(底)板梳状钻孔密闭取样深度达到484 m,测得煤层瓦斯含量较常规取样法平均提高了0.19倍,密闭取样法在煤层瓦斯含量测定精度、探测范围上优于常规取样法;④在瓦斯含量测试方面,除了传统解吸法测试,发展了系列煤矿井下瓦斯含量快速测试装备,可实现最快30 min内测得煤层瓦斯含量,一般用于百米孔内的瓦斯含量测试。提出了煤层瓦斯含量测定密闭取样装备需向小型化、轻量化的方向发展,并能实现随钻密闭取样。在测试上,应根据实际情况确定合理的解吸终止限,并将测试装备和密闭取样装备进一步结合,以实现深孔瓦斯含量快速准确测定。密闭取样技术已成为煤层瓦斯含量大区域精准勘查、预测的主要手段,是煤炭安全高效开采的重要技术保障。 展开更多
关键词 煤层瓦斯含量 定点取样 密闭取样 碎软煤层 硬煤
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超声弹性成像与彩色多普勒超声鉴别三阴性乳腺癌与纤维腺瘤的对比研究
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作者 李秋枫 冯业平 +2 位作者 李辉丽 李香玉 黄振秀 《中国医学装备》 2024年第1期88-92,共5页
目的:探讨超声弹性成像(UE)技术与彩色多普勒超声(CDFI)对三阴性乳腺癌(TNBC)与纤维腺瘤的鉴别诊断价值。方法:选取2021年1月至2022年1月万宁市人民医院收治并经手术病理确诊的50例TNBC患者,将其纳入TNBC组,另选取同期经手术病理证实为... 目的:探讨超声弹性成像(UE)技术与彩色多普勒超声(CDFI)对三阴性乳腺癌(TNBC)与纤维腺瘤的鉴别诊断价值。方法:选取2021年1月至2022年1月万宁市人民医院收治并经手术病理确诊的50例TNBC患者,将其纳入TNBC组,另选取同期经手术病理证实为纤维腺瘤的50例患者纳入纤维腺瘤组。所有患者在行超声检查前均未经任何临床干预,且分别采用UE和CDFI检测,评价其病变区组织软硬程度、彩色血流及弹性评分等。以病理结果为“金标准”,分析UE和CDFI对TNBC和纤维腺瘤的诊断效能。结果:超声影像学特征显示,TNBC组多表现为病灶区域边缘毛刺征,后方回声衰减和高回声晕,且存在腋窝淋巴结转移;纤维腺瘤组多表现为病灶区域边界清晰,病灶形态规则,无微小钙化。UE检测诊断灵敏度为90.91%,特异度为82.14%,准确率为86.00%;CDFI诊断灵敏度为73.08%,特异度为75.00%,准确率为74.00%;联合检测灵敏度为94.23%,特异度为95.83%,准确率为96.00%,其检测效能高于单项检测。结论:UE鉴别诊断TNBC与纤维腺瘤的灵敏度较高,但特异度不高,与CDFI联合检测可以提高鉴别诊断特异度和准确率。 展开更多
关键词 三阴性乳腺癌(TNBC) 彩色多普勒超声(CDFI) 超声弹性成像(UE)技术 组织软硬程度
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我国乡村振兴促进法软法治理机制及其优化适用
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作者 许小莺 《沈阳工业大学学报(社会科学版)》 2024年第1期89-97,共9页
《中华人民共和国乡村振兴促进法》呈现出针对乡村治理的软法进路,在诸多方面发挥了其软法内容所具有的弹性、开放性及补充性作用,是我国探索软法治理的有益尝试,但也存在软法机制未充分发挥的问题。当前,应在软法硬法互动效应的强化、... 《中华人民共和国乡村振兴促进法》呈现出针对乡村治理的软法进路,在诸多方面发挥了其软法内容所具有的弹性、开放性及补充性作用,是我国探索软法治理的有益尝试,但也存在软法机制未充分发挥的问题。当前,应在软法硬法互动效应的强化、授权性的公众参与及治理信息共享等方面着手,弥补乡村振兴促进法软法机制的不足,寻求我国乡村振兴发展的软法治理进路。 展开更多
关键词 乡村振兴促进法 软法 硬法 治理机制 公众参与 信息共享
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环氧树脂-水凝胶软硬复合表界面各向异性摩擦研究 被引量:1
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作者 熊健 王彦斌 +4 位作者 吕阳 姬忠莹 张晓慧 王晓龙 李志强 《摩擦学学报(中英文)》 EI CAS CSCD 北大核心 2024年第3期335-344,共10页
由取向微结构引起的各向异性摩擦学是生物系统中最常见的引起摩擦形式之一.而研究表明,软硬复合的生物表界面在获取各向异性摩擦力时更具有优势.因此,本研究中以最典型的钩状倒刺微结构为研究对象,结合3D打印先进制造技术,通过在仿生取... 由取向微结构引起的各向异性摩擦学是生物系统中最常见的引起摩擦形式之一.而研究表明,软硬复合的生物表界面在获取各向异性摩擦力时更具有优势.因此,本研究中以最典型的钩状倒刺微结构为研究对象,结合3D打印先进制造技术,通过在仿生取向微结构表界面原位复合低模量的水凝胶材料,获得环氧树脂-水凝胶软硬复合表界面.研究结果表明,水凝胶在Fe^(3+)溶液中的配位交联6 h时,其模量为3.6 MPa,相对于环氧树脂(模量为13.6 MPa)为软材料.在5 N载荷下,仿生表界面正方向摩擦力为1.64 N,反方向摩擦力为3.44 N,其各向异性摩擦力最大差值可达1.80 N.本研究中对软硬复合的生物表界面具有一定的理论指导意义,有望在智能摩擦调控和软体机器人等方面发挥一定的作用. 展开更多
关键词 仿生表界面 水凝胶 取向微结构 各向异性摩擦力 软硬复合
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青川刨地里地震滑坡发育特征及其成因机制探讨 被引量:1
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作者 李均益 罗永红 +1 位作者 周赞 南凯 《地震学报》 CSCD 北大核心 2024年第3期514-525,共12页
以“5·12”汶川地震诱发的青川县刨地里滑坡为例,现场调查了滑坡的地质特征,并基于离散元软件(UDEC)分析了1号滑坡动力响应及变形破坏过程,探讨了滑坡的成因机制。现场调查表明,刨地里1号滑坡具有近水平“上硬下软”的地层结构,其... 以“5·12”汶川地震诱发的青川县刨地里滑坡为例,现场调查了滑坡的地质特征,并基于离散元软件(UDEC)分析了1号滑坡动力响应及变形破坏过程,探讨了滑坡的成因机制。现场调查表明,刨地里1号滑坡具有近水平“上硬下软”的地层结构,其中石坎断层穿过了滑坡后缘;滑坡堆积体的岩性分带特征表明,刨地里1号滑坡下部千枚岩先于上部硅质岩被破坏,且破坏时间早于2号和3号滑坡;数值模拟研究揭示,峰值加速度放大效应在断层带附近的千枚岩内最强,其放大系数达6.79,导致下层千枚岩首先沿陡倾面产生拉裂破坏,随后上层硅质岩体产生拉裂破坏,结果与现场调查堆积物特征较吻合;断层和上硬下软的地层结构对刨地里滑坡动力响应、变形及破坏起到了控制作用。该研究可为上硬下软且含断层的地震滑坡的评价提供参考。 展开更多
关键词 “5·12”汶川地震 地震滑坡 上硬下软地层 石坎断层 成因机制
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刚柔并济:党建化解基层治理悖论的逻辑--以西安市G社区“党建+片区大物业”为例 被引量:1
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作者 黄少卓 寇晓东 《陕西行政学院学报》 2024年第1期28-32,共5页
基层治理是国家行政力量与社会自治力量共同作用的交叉场域,形成了两种力量之间的张力,并围绕此张力凸显出三重治理悖论。基层党建是沟通国家与社会的桥梁。在此背景下,党建引领的治理逻辑如何平衡国家行政力量与社会自治力量之间的悖论... 基层治理是国家行政力量与社会自治力量共同作用的交叉场域,形成了两种力量之间的张力,并围绕此张力凸显出三重治理悖论。基层党建是沟通国家与社会的桥梁。在此背景下,党建引领的治理逻辑如何平衡国家行政力量与社会自治力量之间的悖论?对西安市G社区“党建+片区大物业”的治理过程进行观察,发现党建在基层治理中表现出刚柔并济的治理逻辑。其中,正式结构、强关系与规范手段构成了党建治理的刚性三角,而非正式结构、弱关系与情感手段则构成了党建治理的柔性三角。党建的治理逻辑不仅展现了党建引领基层治理的灵活方案,也揭示了政党在场下国家-社会关系的形塑机制。 展开更多
关键词 基层治理 党建引领 治理悖论 刚柔并济
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钠离子电池软硬碳负极材料研究进展
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作者 曾杰 张文华 +6 位作者 王帅 彭望 缪胤宝 刘伟昊 刘嘉 陈哲 陈显彪 《南昌工程学院学报》 CAS 2024年第3期75-81,共7页
钠离子电池,因与锂离子电池具有类似的工作原理,且无资源限制、成本相对较低,具有在大规模能源存储领域中发挥重要作用的潜力,近年来受到了广泛关注。负极材料作为钠离子电池的关键组成部分,其结构直接影响着电池的性能。因此,本文从基... 钠离子电池,因与锂离子电池具有类似的工作原理,且无资源限制、成本相对较低,具有在大规模能源存储领域中发挥重要作用的潜力,近年来受到了广泛关注。负极材料作为钠离子电池的关键组成部分,其结构直接影响着电池的性能。因此,本文从基本概念、结构特点、性能优劣和储钠机理等方面介绍了钠离子电池的碳基负极材料,包括软碳、硬碳和软硬碳三种类型;详细阐述了软碳和硬碳各自存在的不足及改进方法,重点归纳了兼具软碳和硬碳优势的软硬碳复合材料的研究状况和制备方法,并分析了软硬碳材料在钠离子电池负极材料领域的应用潜力。 展开更多
关键词 钠离子电池 负极材料 硬碳 软碳 软硬碳
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基于PINNs算法的一维潜水流方程的渗流参数反演
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作者 舒伟 孟胤全 +2 位作者 邓芳 蒋建国 吴吉春 《南京大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第2期317-327,共11页
在地下水领域中,渗流参数反演有助于了解地下水流动的性质,帮助确定地下水资源的分布、移动和质量,这对于地下水资源管理、水文模型开发和地下水补给的可持续性非常重要.近年来,神经网络方法快速发展,然而其针对潜水流渗流参数反演的研... 在地下水领域中,渗流参数反演有助于了解地下水流动的性质,帮助确定地下水资源的分布、移动和质量,这对于地下水资源管理、水文模型开发和地下水补给的可持续性非常重要.近年来,神经网络方法快速发展,然而其针对潜水流渗流参数反演的研究较少.基于此,首次将物理信息神经网络(Physics-Informed Neural Networks,PINNs)方法结合软硬约束设置来解决潜水含水层渗透系数反演问题,以一维稳态非均质潜水流以及非稳态均质潜水流(含溶质运移)的渗透系数反演为例,对比了不同问题中PINNs软约束方法(PINNs-S)和硬约束方法(PINNs-H)反演渗透系数的表现.PINNs算例结果表明,PINNs算法反演渗透系数具有较高的计算精度.此外,PINNs硬约束算法和软约束算法各有优劣,在实际应用中应根据具体问题和实验效果来合理选择. 展开更多
关键词 物理信息神经网络 潜水 硬约束 软约束 渗流参数反演
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