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Classification of disturbance vectors for collision attack in SHA-1

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Science China(Information Sciences) 2015年第11期58卷 103-112页

作者： TANG YuChen ZENG guang han WenBao The Information Engineering University

A good disturbance vector is one of the key techniques to find SHA-1 collisions and to construct valid differential paths. The main work of this paper is to classify the types of the optimal disturbance ***, we improve the EEM disturbance vectors search algorithm by Manuel. We increase the Hamming weight of information window from 4 to 6, with 244 time complexity, which is 28 times better than that of Manuel’s work. Based on this result, we prove that there are only two types of the optimal disturbance vectors, type-I and type-II, which have minimum weight of 25 in the last 60 of the 80 expanded words, in the total 2512 disturbance vectors searching space.

关键词： Hash function SHA-1 collision attack disturbance vector extended expanded message

牛膝化学成分和药理作用研究进展及其质量标志物(Q-Marker)预测分析

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天然产物研究与开发 2024年第8期36卷 1432-1444页

作者：韩永光谭雅兰张超云卞华河南中医药大学药学院郑州450046 南阳理工学院河南张仲景方药与免疫调节重点实验室南阳473004

牛膝在《神农本草经》中被列为上品,近几年研究证实牛膝的化学成分主要包括甾体、三萜皂苷、多糖、挥发油等化合物,具有抗炎镇痛、调节免疫、抗骨质疏松、保护心血管等药效。本文从牛膝的植物亲缘性,牛膝特有性、有效性、可测性化学成... 详细信息

牛膝在《神农本草经》中被列为上品,近几年研究证实牛膝的化学成分主要包括甾体、三萜皂苷、多糖、挥发油等化合物,具有抗炎镇痛、调节免疫、抗骨质疏松、保护心血管等药效。本文从牛膝的植物亲缘性,牛膝特有性、有效性、可测性化学成分和炮制后化学成分等方面,对牛膝的质量标志物(quality marker,Q-Marker)进行预测分析,牛膝甾酮A、25 S-牛膝甾酮、25 R-牛膝甾酮、齐墩果酸-3-O-β-D-(6′-丁酯)-吡喃葡萄糖醛酸苷、齐墩果酸-3-O-β-D-(6′-甲酯)-吡喃葡萄糖醛酸苷、β-蜕皮甾酮等可作为牛膝质量标志物,为建立牛膝质量评价体系和深入研究其药理作用提供依据。

关键词：牛膝化学成分药理作用质量标志物

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多孔介质低渗测试气体周期振荡法理论研究

岩土力学 2024年第7期45卷 1939-1956页

作者：王威陈卫忠杨典森杨光华周小文袁明道史永胜刘宜杰广东省水利水电科学研究院广东广州510610 广东省岩土工程技术研究中心广东广州510640 华南理工大学土木与交通学院广东广州510640 中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室湖北武汉430071 武汉大学土木建筑工程学院湖北武汉430072

目前,多孔介质低渗测试主要采用高精度气体稳态法和气体脉冲衰减法,缺少对气体周期振荡法的深入探讨和分析。基于气体周期振荡法基本原理和试验方法,提出了3种基于不同控制方式模拟生成周期波气压边界条件的方法,以及在试样上游和下游... 详细信息

目前,多孔介质低渗测试主要采用高精度气体稳态法和气体脉冲衰减法,缺少对气体周期振荡法的深入探讨和分析。基于气体周期振荡法基本原理和试验方法,提出了3种基于不同控制方式模拟生成周期波气压边界条件的方法,以及在试样上游和下游分别设置1个体积可调的气体储存容器的试验设备方案。基于孔隙流体介质的讨论,将Fischer等提出的以不可压缩流体为渗流介质的周期法理论解,推广到以可压缩流体为渗流介质的情况,扩大了周期法理论解的适用范围,并讨论了各参数之间的物理意义及其联系。基于气体周期振荡法理论解,进行了2个特例分析,优化了理论解中复杂分项的处理。通过一系列正交对照计算案例,对比了气体周期振荡法理论解和数值解的计算结果,讨论了渗透率、孔隙率、下游容器体积、试样直径和长度等对试验过程的影响,验证了理论解的准确性和可靠性,并对理论解的不足进行了说明,在此基础上,给出了气体周期振荡法试验的优化设计策略。

关键词：气体周期振荡法渗透率储存系数理论研究

Adsorption behavior and mechanism of copper ions in the sulfidization flotation of malachite

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International Journal of Mining Science and Technology 2022年第4期32卷 897-906页

作者： han Wang Shuming Wen guang han Yongxin He Qicheng Feng State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource EngineeringKunming University of Science and TechnologyKunming 650093China State Key Laboratory of Mineral Processing Beijing 100160China Yunnan Key Laboratory of Green Separation and Enrichment of Strategic Mineral Resources Kunming University of Science and TechnologyKunming 650093China Inter Mongolia Xingye Mining Company Limited Chifeng 024028China

Malachite is one of the main minerals used for the industrial enrichment and recovery of copper oxide resources, and copper ions are unavoidable metal ions in the flotation pulp. The microflotation, contact angle, and adsorption experiments indicated that pretreatment with an appropriate concentration of copper ions could improve the malachite recovery, and the addition of excess copper ions reduced the hydrophobicity of the malachite surface. The results of zeta potential tests indicated that sodium sulfide and butyl xanthate were also adsorbed on the surface of malachite pretreated with copper ions. X-ray photoelectron spectroscopy(XPS) results indicated that —Cu—O and —Cu—OH bonds were formed on the surface of the samples. After pretreatment with an appropriate concentration of copper ions, the number of —OH groups on the mineral surface decreased, whereas the number of Cu—S groups on the mineral surface increased, which was conducive to the sulfidization of malachite. After adding a high concentration of copper ions, the —OH groups on the mineral surface increased, whereas the number of Cu—S groups decreased, which had an adverse effect on the sulfidization flotation of malachite. Time-of-flight secondary ion mass spectrometry showed that pretreatment with copper ions resulted in a thicker sulfidization layer on the mineral surface.

关键词： Malachite Sulfidization flotation Copper ions Adsorption

Measurement on soil deformation caused by expanded-base pile in transparent soil using particle image velocimetry (PIV)

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Journal of Mountain Science 2017年第8期14卷 1655-1665页

作者： QI Chang-guang ZHENG Jin-hui ZUO dian-jun CHEN Geng Faculty of Architectural Civil Engineering and EnvironmentNingbo University Tianjin Research Institute for Water Transport Engineering M.O.T. Geotechnical Research Institute Hohai University

A new small-scale geotechnical physical model in 1-g and unconfined condition, combining the transparent soil, close-range photogrammetry and particle image velocimetry(PIV), was employed, which provides a non-intrusively internal deformation measurement approach to monitor the internal deformation of soil caused by expanded-base pile jacking with casing. The transparent soil was made of fused quartz and its refractive index matched blended oil, adding reflective particles(glass beads). Closerange photogrammetry was employed to record the images of the process of casing jacking and extraction in transparent soil, allowing the use of Matlab-based Geo-PIV to figure out the displacement field converted from image space to object space. Analysis of test results indicates that the maximum displacement caused by casing jacking for expandedconical-base pile is decreased by 29% compared with that for expanded-flat-base pile. The main movement happens at the early stage of casing extraction. The maximum displacement caused by casing extraction for the conical base is about 43% of that for the flatbase, while the affected zone caused by casing extraction for the conical base accounts for about 1/3 of that for the flat base. The contraction for horizontal displacements tends to decrease with the depth increasing. By contrast, the contraction under pile base decreases with the increasing of displacement. The displacements generated by jacking a conventional pile having a diameter equal to the casing diameter of the expanded-base pile were comparable to the net displacement taking place due to expanded-base pile installation for the conical base pile.

关键词： Geotechnical physical model Expanded-base pile Transparent soil Particle image velocimetry(PIV) Close-range photogrammetry

Transparency and reporting characteristics of randomized controlled trials with Chinese herbal medicine formulas interventions

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Frontiers of Medicine 2024年第4期18卷 757-761页

作者： Juan Wang Dongni Shi Yaochen Wang Xuanqi Zhang han Li Xihong Wang Shufeng Luo Lihan Hu Jiashuai Deng Lin Zhang Chung Tai Lau Chung Wah Cheng Fei han Ji Li Ping Wang Aiping Lyu Zhaoxiang Bian Xuan Zhang Institute for Research and Continuing Education Hong Kong Baptist UniversityShenzhen518057China Chinese EQUATOR Centre Hong Kong Baptist UniversityHKSAR999077China School of Traditional Chinese Medicine Tianjin University of Chinese MedicineTianjin301617China School of Chinese Medicine Beijing University of Chinese MedicineBeijing100105China School of Chinese Medicine Hong Kong Baptist UniversityHKSAR999077China Department of Pediatrics Guang’anmen HospitalChina Academy of Chinese Medical SciencesBeijing100053China Xiyuan Hospital China Academy of Chinese Medical SciencesBeijing100091China Centre for Chinese Herbal Medicine Drug Development Hong Kong Baptist UniversityHKSAR999077China

To enhance the clarity and transparency of reporting in trials involving Chineseherbal medicine(CHM)formulas,the CONSORT extension specifically tailored for CHM formulas(CONSORT-CHM Formulas 2017)was introduced in 2017[1].This statement,along with its corresponding checklist,outlines key elements essential for reporting in randomized controlled trials(RCTs)related tothe rationale,design,analysis,and interpretation of interventions using CHM *** CONSORT-CHM Formulas 2017 elaborated on 7 of 25 CONSORT checklist items,namely title,abstract and keywords,backgrounds and objectives,participants,interventions,outcomes,generalizability,and interpretation.

关键词： formulas statement rational

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汉代墓门羊首浮雕研究

中原文物 2024年第3期 72-78页

作者：齐广南开大学历史学院天津300350

汉代墓葬中常在墓门门楣处装饰羊首浮雕。汉代羊首浮雕出现在西汉晚期。东汉中后期以来,在山东及周边地区以笼头装饰的羊首浮雕大量出现,是骑羊与羊车的象征。墓门使用羊首浮雕,与汉代门上悬挂羊首的风俗有关。通过比对墓门羊首浮雕、... 详细信息

汉代墓葬中常在墓门门楣处装饰羊首浮雕。汉代羊首浮雕出现在西汉晚期。东汉中后期以来,在山东及周边地区以笼头装饰的羊首浮雕大量出现,是骑羊与羊车的象征。墓门使用羊首浮雕,与汉代门上悬挂羊首的风俗有关。通过比对墓门羊首浮雕、地上圆雕石羊、骑羊与羊车图像等材料,可知墓门羊首浮雕是仙人骑羊的符号化象征。墓门羊首浮雕不仅有吉祥辟邪之意,也是当时神仙思想的表达。

关键词：羊首浮雕骑羊辟邪升仙

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活力海岸概念辨析及评价指标体系构建

中国环境科学 2024年第6期44卷 3387-3394页

作者：古雄杰邓建明曾剑韩宇张广之王菲菲全占军中国环境科学研究院北京100012 兰州大学生态学院甘肃兰州730030 浙江省水利河口研究院(浙江省海洋规划设计研究院) 浙江杭州310000

海岸带具有重要的生态系统服务价值,但是由于自然灾害以及人类不合理的开发利用,海岸带遭到严重侵蚀和破坏.传统的海岸硬质结构防御模式已经不足以面对不断变化的沿海条件甚至加剧海岸侵蚀,因此基于自然解决方案的“活力海岸”越来越受... 详细信息

海岸带具有重要的生态系统服务价值,但是由于自然灾害以及人类不合理的开发利用,海岸带遭到严重侵蚀和破坏.传统的海岸硬质结构防御模式已经不足以面对不断变化的沿海条件甚至加剧海岸侵蚀,因此基于自然解决方案的“活力海岸”越来越受到人们的关注.本研究剖析了活力海岸内涵,提出了活力海岸核心要素,构建了活力海岸指标体系.采用德尔菲(Delphi)法开展2轮专家函询,通过计算专家积极性､专家权威程度､专家意见集中程度与协调系数,判断指标体系构建的可靠性;基于界值法筛选指标并结合专家意见构建活力海岸评价指标体系.活力海岸评价指标体系分为三个层次,即目标层、准则层和指标层,准则层分为“资源环境适宜性”､“资源环境可持续性”、“生态韧性”、“社会经济支撑性”4类,指标层包括一级指标13项和二级指标36项.活力海岸的核心特征是“基于自然元素”,通过采用自然材料或自然与人工材料相结合的技术保护、恢复和增强海岸带自然栖息地,最终促使海岸带资源环境条件和经济社会发展达到可持续发展的状态.我国目前活力海岸相关研究较少,本研究构建的活力海岸评价指标体系一定程度上填补了活力海岸管理模式的空白.

关键词：活力海岸海岸侵蚀德尔菲法指标体系

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高危儿神经发育障碍预防性早期干预研究进展

中国当代儿科杂志 2024年第3期26卷 297-301页

作者：农绍汉余卫红李翠红(综述) 周晓光(审校) 广东省人民医院/广东省医学科学院新生儿科广东广州510080 中山大学附属第八医院新生儿科广东深圳518033 云南省文山壮族苗族自治州人民医院新生儿科云南文山663000

儿童神经发育障碍已成为影响全球儿童健康的重大公共卫生问题。国内目前对高危儿一般采用“早期诊断、早期治疗”的干预模式。近年来,国外开始探讨高危儿神经发育障碍的预防性早期干预新技术,并取得较好效果。该文对高危儿神经发育障碍... 详细信息

儿童神经发育障碍已成为影响全球儿童健康的重大公共卫生问题。国内目前对高危儿一般采用“早期诊断、早期治疗”的干预模式。近年来,国外开始探讨高危儿神经发育障碍的预防性早期干预新技术,并取得较好效果。该文对高危儿神经发育障碍预防性早期干预的开始时机、方法和干预模式等进行综述,以期提高临床医生对高危儿神经发育障碍预防性早期干预技术的认识水平,促进此干预技术在我国的临床研究与应用,降低高危儿神经发育障碍的发生率。

关键词：神经发育障碍预防性干预高危儿