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高耐水聚合物水泥防水涂料及其应用性能研究

新型建筑材料 2024年第1期51卷 133-136,144页

作者：韩光孟宪宇尹新民李婧北京东方雨虹防水技术股份有限公司特种功能防水材料国家重点实验室北京100176

从JS防水涂料的耐水机理出发,针对性地设计了由聚合物中活性官能团(羧基)与交联剂形成的后交联结构,减弱了水分子对聚合物分子间的增塑作用及对聚合物分子与无机填料界面力的破坏作用,研制了一种具有优异耐水性能的JS防水涂料。该涂料... 详细信息

从JS防水涂料的耐水机理出发,针对性地设计了由聚合物中活性官能团(羧基)与交联剂形成的后交联结构,减弱了水分子对聚合物分子间的增塑作用及对聚合物分子与无机填料界面力的破坏作用,研制了一种具有优异耐水性能的JS防水涂料。该涂料在长期浸水后,仍保持较好的物理力学性能,吸水率1.6 MPa,且浸水1年后表观无变化。

关键词： JS防水涂料耐水性建筑防水材料

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基于机器学习的钻井液流变参数智能识别方法

煤田地质与勘探 2024年第5期52卷 183-192页

作者：刘长晔杨现禹蔡记华王韧王建龙代凡斐郭万阳蒋国盛冯洋中国地质大学(武汉)工程学院湖北武汉430074 中国石油集团工程技术研究院有限公司北京102206

钻井液流变性是钻井液流动和变形的特性,对于携带与悬浮岩屑、提高钻进速度至关重要,准确掌握钻井液流变参数是保证井眼清洁与高效钻进的前提。提出一种基于卷积神经网络(Convolu-tionalNeuralNetwork,CNN)的钻井液流变参数智能识别方法... 详细信息

钻井液流变性是钻井液流动和变形的特性,对于携带与悬浮岩屑、提高钻进速度至关重要,准确掌握钻井液流变参数是保证井眼清洁与高效钻进的前提。提出一种基于卷积神经网络(Convolu-tionalNeuralNetwork,CNN)的钻井液流变参数智能识别方法,通过磁力搅拌产生稳定的钻井液流动图像,利用多种数据增强方法增加图像数量并建立数据库,增强模型的鲁棒性和泛化能力。优化AlexNet卷积神经网络算法,构建钻井液流变参数识别模型。将数据库划分为训练集:验证集:测试集=7:2:1,对训练集进行迭代训练并通过验证集调整参数获得最佳拟合模型。此外,运用混淆矩阵、卷积核可视化技术和类激活技术(Gradient-weighted Class Activation Mapping,Grad-CAM)对模型进行多方位评估。结果表明:(1)钻井液流变参数识别模型对钻井液塑性黏度测试的宏精确率为95.2%,宏召回率为94.7%,宏F1值为0.95。(2)对钻井液表观黏度测试的宏精确率为91.6%,宏召回率为91.5%,宏F1值为0.90。(3)利用卷积核可视化技术和Grad-CAM对特征提取进行可视化处理,发现钻井液波纹形状和大小会影响模型流变参数识别准确度。(4)室内测试结果表明,该模型的测试误差为±2 mPa·s,在设计允许范围以内,具有较高的识别精确度和稳定性。所提出的钻井液流变参数实时智能识别方法可为安全、快速和准确地进行钻井液流变性测试提供智能化技术思路。

关键词：钻井液流变参数机器学习卷积神经网络智能识别

SIRT6在肝纤维化形成进程中的作用及其机制

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中国病理生理杂志 2024年第9期40卷 1652-1659页

作者：林夏萍黄仙玉孙健李映莹徐云燕黄波杨媛吴芹遵义医科大学基础药理教育部重点实验室暨特色民族药教育部国际合作联合实验室贵州遵义563006 遵义医科大学附属医院消化内科贵州遵义563003

目的:探讨沉默信息调节因子6(silent information regulator 6,SIRT6)对四氯化碳(carbon tetrachloride,CCl_(4))诱导的小鼠肝纤维化作用和机制,以及肝星状细胞在SIRT6沉默后其下游通路的表达变化。方法:将30只雄性C57BL/6J小鼠随机分... 详细信息

目的:探讨沉默信息调节因子6(silent information regulator 6,SIRT6)对四氯化碳(carbon tetrachloride,CCl_(4))诱导的小鼠肝纤维化作用和机制,以及肝星状细胞在SIRT6沉默后其下游通路的表达变化。方法:将30只雄性C57BL/6J小鼠随机分为正常对照组(n=6)和模型组(造模2、4、8、12周,n=24),采用腹腔注射CCl_(4)制备肝纤维化小鼠模型,每周2次,持续12周。检测各组小鼠血清丙氨酸氨基转移酶(alanine aminotransferase,ALT)、天门冬氨酸氨基转移酶(aspartate aminotransferase,AST)含量评估肝损伤;HE、Masson染色观察小鼠肝脏病理学改变;免疫组织化学染色检测小鼠肝脏α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)的表达;Western blot检测肝脏α-SMA、SIRT6、第9位赖氨酸乙酰化的组蛋白H3(acetyl histone H3 at Lys9,H3K9ac)、第56位赖氨酸乙酰化的组蛋白H3(acetyl histone H3 at Lys56,H3K56ac)、白细胞介素1β(interleukin-1β,IL-1β)和IL-18蛋白的表达。将大鼠肝星状细胞(hepatic stellate cells-T6,HSC-T6)进行SIRT6基因沉默,分为NC siRNA组和SIRT6 siRNA组。Western blot检测SIRT6、H3K9ac和H3K56ac蛋白的表达。结果:与正常对照组比较,模型组小鼠血清中ALT和AST含量均显著升高(P12周模型组中肝脏α-SMA表达显著增加(P1β和IL-18表达水平在8、12周时明显升高(P1β和IL-18的表达升高,加剧炎症反应而促进肝纤维化进程,提示SIRT6的表达异常参与了肝纤维化进程的发展。

关键词：肝纤维化四氯化碳肝星状细胞沉默信息调节因子6 炎症因子

Aeroservoelastic model based active control for large civil aircraft

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Science China(Technological Sciences) 2010年第4期53卷 1126-1137页

作者： FAN Yong1,ZHU JiHong1,HU ChunHua2,MENG xianyu1,WANG XiangYang2 & GE AiXue1 1 Department of Computer Science and Technology,Tsinghua University,Beijing 100084,China 2 School of Astronautics and Aeronautics,Tsinghua University,Beijing 100084,China Department of Computer Science and Technology Tsinghua University Beijing China School of Astronautics and Aeronautics Tsinghua University Beijing China

A modeling and control approach for an advanced configured large civil aircraft with aeroservoelasticity via the LQG method and control allocation is *** models and implementation issues for the multi-input/multi-output(MIMO) aeroservoelastic system simulation developed for a flexible wing with multi control surfaces are described.A fuzzy logic based optimization approach is employed to solve the constrained control allocation problem via intelligently adjusting the components of output vector and find a proper vector in the attainable moment set(AMS) *** basic idea is to minimize the L2 norm of error between the desired moment and achievable moment using the designing freedom provided by redundantly allocated actuators and control *** the constraints of control surfaces,in order to obtain acceptable performance of aircraft such as stability and maneuverability,the fuzzy weights are updated by the learning algorithm,which makes the closed-loop system ***,an application example of flight control designing for the advanced civil aircraft is discussed as a *** studies we have performed showed that the advanced configured large civil aircraft has good performance with the proper designed control law designed via the proposed *** gust alleviation and flutter suppression are applied with the synergetic effects of elevator,ailerons,equivalent rudders and *** results show good closed loop performance and meet the requirement of constraint of control surfaces.

关键词： modeling active control aeroelastic flutter suppression control allocation

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紫菜薹叶绿体全基因组序列及其系统发育分析

西北农业学报 2024年第8期33卷 1483-1494页

作者：王传之周贤玉李扬眉肖婉钰王雨凤任海龙宿州学院生物与食品工程学院安徽宿州234000 广州市农业科学研究院广州510308 广东省农业科学院作物研究所/广东省农作物遗传改良重点实验室广州510640

紫菜薹(Brassica rapa ***)是十字花科芸薹属白菜亚种中的一个变种,通过Illumina高通量测序平台,对其叶绿体基因组进行测序、组装和注释。结果表明,紫菜薹叶绿体基因组为典型的四分环状结构,大小为153483 bp,GC含量为36.36%,由长度为832... 详细信息

紫菜薹(Brassica rapa ***)是十字花科芸薹属白菜亚种中的一个变种,通过Illumina高通量测序平台,对其叶绿体基因组进行测序、组装和注释。结果表明,紫菜薹叶绿体基因组为典型的四分环状结构,大小为153483 bp,GC含量为36.36%,由长度为83282 bp的大单拷贝区(LSC)、17775 bp的小单拷贝区(SSC)和1对各26213 bp的反向重复区(IRa/IRb)组成。基因组注释共得到132个基因,包括:87个蛋白编码基因,37个tRNA和8个rRNA。共鉴定到313个简单重复序列(SSR)和37个散在重复序列。密码子偏好性分析发现存在偏好使用A/U碱基结尾的现象。边界分析和序列变异分析显示,芸薹属叶绿体基因组非常保守,其中SSC区差异性最大,变异程度最高,IR区差异性最小,最为保守。基于叶绿体基因组序列的系统发育分析表明,紫菜薹在分类上与白菜的其他变种在一个小分支中。研究结果可为芸薹属植物,特别是白菜种的分类学、系统学和生物地理学研究提供参考。

关键词：白菜紫菜薹叶绿体基因组系统发育分析

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心舒宝片对心肌梗死后小鼠心功能及凝溶胶蛋白的影响

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中华中医药杂志 2024年第5期39卷 2260-2265页

作者：张丰荣江雪刘妹李贤煜肖洪贺杨洪军中国中医科学院中药研究所北京100700 中国中医科学院医学实验中心北京100700

目的:探究心舒宝片对心肌梗死(MI)后小鼠心功能的保护作用及其对凝溶胶蛋白(GSN)的影响。方法:结扎左冠状动脉前降支建立MI模型。C57BL/6J雄性小鼠随机分为假手术组,模型组,心舒宝片高、低剂量组和卡托普利组,每组10只。心舒宝片低、高... 详细信息

目的:探究心舒宝片对心肌梗死(MI)后小鼠心功能的保护作用及其对凝溶胶蛋白(GSN)的影响。方法:结扎左冠状动脉前降支建立MI模型。C57BL/6J雄性小鼠随机分为假手术组,模型组,心舒宝片高、低剂量组和卡托普利组,每组10只。心舒宝片低、高剂量组分别灌胃0.26、0.52 g·kg^(-1)·d^(-1)心舒宝片混悬液,卡托普利组灌胃4.875 mg·kg^(-1)·d^(-1)卡托普利片混悬液,假手术组和模型组灌胃等体积双蒸水,连续灌胃4周,采用超声多普勒检测检测小鼠的心脏功能,单细胞测序技术解析MI影响的关键细胞类型和基因,Western Blot检测心肌组织中关键蛋白GSN的表达情况。结果:与模型组比较,心舒宝片高剂量组小鼠心脏指数显著减少(P1、Myl3和Tnnt2等,成纤维细胞富集到GSN、COL1a1和COL3a1,内皮细胞富集到PECAM1、EGFL7和VEGFA,KEGG涉及到心肌收缩、肥厚型心肌病、扩张型心肌病等;心舒宝片高剂量组GSN表达显著减少(P<0.05)。结论:心舒宝片能减少MI小鼠心肌组织的GSN蛋白表达,减轻心脏纤维化,进而逆转左心室重构并改善左心室功能,提高MI小鼠的生活质量。

关键词：心舒宝片心肌梗死单细胞测序凝溶胶蛋白心脏纤维化

Phytolith records of the climate change since the past 15000 years in the middle reach of the Yangtze River in China

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Frontiers of Earth Science 2012年第1期6卷 10-17页

作者： Yansheng GU Hanlin WANG xianyu HUANG Hongxia PENG Junhua HUANG State Key Laboratory of Geobiology and Environmental Geology(BGEG) China University of GeosciencesWuhan 430074China Hubei Key Laboratory of Wetland Evolution&Eco-Restoration(WEER) China University of GeosciencesWuhan 430074China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China

Based on 14C dating and core sediments survey, phytolith records are employed to reconstruct paleovegetation and paleoclimate in the Jianghan Plain in the middle reach of the Yangtze River. Phytoliths identified are assigned into 21 well-described morphotypes and divided into four groups （Poaceae, fern, coniferous and broad-leaved）. The phytolith assemblages together with warmth index （Iw） are divided into 18 ecological zones, which reflect a complete vegetation history related to climate change in the middle reach of the Yangtze River during the past 15000 years. On the basis of the correlation ofphytolith records with the paleoclimatic indicators from stalagmite, peatland, North Atlantic deep-sea sediments, Loess Plateau of Central China, and Arabic Sea sediments, eight climatic phases are identified included Last Glacial Maximum （LGM）（20- 14.8 cal kaBP）, Last Deglaciation （LDG）（14.8-11.9 cal kaBP）, low-temperature phase in the Early Holocene （11.9-8 cal kaBP）, Holocene Opti- mum （8-4.9cal kaBP）, Holocene Katathermal （4.9- 1.1 cal kaBP）, Medieval Warmth Period （MWP）（1.1- 0.7 cal kaBP）, Little Ice Age （LIA）（0.7-0.15 cal kaBP）, and Modem Warming （0.15 cal kaBP-present）. Climatic events such as Bolling-Allerod warm intervals, Older Dryas, Inter-Allerod Cold Period, and Younger Dryas, and eight Holocene Bond events （B1-8） have been identified since the LDG. Our results demonstrate that the evolution of the climate in the research area has a strong link with the Indian Summer Monsoon （SW Monsoon）, Asian Summer Monsoon （SE Monsoon）, and Holocene events in North Atlantic simultaneously, which might indicate that solar variability affects the Earth surface climate system at the centennial and millennial scales.

关键词： core sediments middle reach of the YangtzeRiver 15000 years phytolith assemblages paleovegetation,paleoclimate

Optimization of acid digestion conditions on the extraction of fatty acids from stalagmites

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Frontiers of Earth Science 2012年第1期6卷 109-114页

作者： Canfa WANG Hongbin ZHANG xianyu HUANG Junhua HUANG Shucheng XIE State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China

Lipids in stalagmites have been shown the potential for the paleoclimate reconstruction. However, the low lipid content leads to the difficulty in gaining high resolution lipid record in stalagmites because large mass of samples are required. Previous studies have validated that the acid digestion can improve the yield of lipids, especially fatty acids （FAs） and 3-hydroxy fatty acids （3- OH-FAs）. In order to obtain more content of FAs and 3- OH-FAs with limited stalagmite sample weight, we investigate here how the acid digestion conditions （HC1 concentration, heating temperature and time duration） could affect the yields of FAs and 3-OH-FAs. Under different concentration of HC1, from 2.0 to 6.0 mol/L, the FAs keep the same step in content variation with 3-OH- FAs, and the highest yields of both two appeared under the 3 mol/L HCl. The content of 3-OH-FAs increases posi- tively with the heating temperature from 80℃ to 150℃, while FAs showed the highest content at 130℃. Both of FAs and 3-OH-FAs firstly increased to a high content and then decreased as the heating time duration varies from 1.0 to 4.0 h, with the highest yields of both two being at 3.0 h. Consequently, we suggest the optimized acid digestion condition is under 3 mol/L HC1, heating at 130℃ for 3 h and 5 g of each stalagmite sample are sufficient for the lipid analysis.

关键词： stalagmite lipids acid digestion optimization

Creep Behaviors of FGH95 Powder Ni-Base Superalloy

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Chinese Journal of Aeronautics 2009年第4期22卷 444-448页

作者： Tian Sugui Liu Yang Zhou Xiaoming Zhao Zhonggang Bao xianyu Wang Wuxiang School of Materials Science and Engineering Shenyang University of Technology Shenyang 110023 China Beijing Institute of Aeronautical Materials Beijing 100095 China

This article makes an investigation into the creep behavior and deformation features of FGH95 powder Ni-base superalloy by means of creep curves and microstructural observation. Results show that this superalloy exposes obvious sensibility to the applied temperature and stresses in the experimental range. Microstructure of the alloy consists of γ＇ phase of various sizes and dispersed carbide particles precipitated in the wider crystal boundaries between the powder particles. During the creep, the deformation of the alloy occurs in the form of singleor double-oriented slipping inside the grains, and some of the finer carbide particles are precipitated near the slipping traces. The wide grain boundaries might be broken into the finer grains due to severe deformation. The deformation mechanism of the alloy during creep is thought to be the activation of dislocations of double-oriented slipping, including （1/2）〈 110〉 dislocation inside the γ matrix phase and 〈110〉 super-dislocation inside the γ＇phase. The formation of the stacking faults and （1/3）〈112〉 super-Shockleys partial dislocation configuration is attributed to the decomposition of 〈 110〉 super-dislocation in the γ＇ phase.

关键词： FGH95 powder Ni-base superalloy microstructure creep deformation features