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基于HRM技术开发水稻糊化温度基因ALK功能标记 被引量:1
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作者 王军 周晶 +9 位作者 陶亚军 李文奇 朱建平 范方军 王芳权 许扬 陈智慧 蒋彦婕 李霞 杨杰 《中国水稻科学》 CAS CSCD 北大核心 2024年第1期106-110,共5页
【目的】糊化温度是影响稻米蒸煮食味品质的重要指标,ALK是控制水稻糊化温度的主效基因,开发可快速高通量鉴定ALK基因型的功能标记有助于提高水稻品质改良的效率。【方法】根据ALK基因4198位、4329位和4330位存在的单碱基差异,设计基于... 【目的】糊化温度是影响稻米蒸煮食味品质的重要指标,ALK是控制水稻糊化温度的主效基因,开发可快速高通量鉴定ALK基因型的功能标记有助于提高水稻品质改良的效率。【方法】根据ALK基因4198位、4329位和4330位存在的单碱基差异,设计基于HRM技术检测的基因功能标记。【结果】通过PCR检测结合测序分析,筛选了ALK基因2个功能区域的功能标记ALKH4、ALKH5。利用ALKH4、ALKH5对81份籼稻品种、279份粳稻品种进行了ALK基因型检测,结果发现,16份粳稻和19份籼稻为G-GC基因型;51份粳稻为A-GC基因型;212份粳稻和62份籼稻为G-TT基因型。【结论】基于HRM技术开发的基因功能标记ALKH4、ALKH5可以快速高通量鉴定控制糊化温度ALK不同基因型,具有重要的应用价值。 展开更多
关键词 水稻 糊化温度 ALK 功能标记 hrm技术
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基于UHPLC-Q-Exactive Orbitrap HRMS技术结合化学计量学方法的不同干燥处理杜仲叶成分分析 被引量:1
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作者 李淑芳 王会锋 +6 位作者 郝学飞 胡永建 李圆圆 马风莲 冯书惠 杨亚琴 于永杰 《分析测试学报》 CAS CSCD 北大核心 2024年第2期213-225,共13页
采用基于液质联用的非靶向代谢组学技术结合化学计量学数据自动解析软件AntDAS-LCHRMS分析了4种不同干燥处理(冻干、热泵烘干、电热烘干、晒干)杜仲叶样本中的化合物。杜仲叶样本数据由超高效液相色谱-四极杆-静电场轨道阱高分辨质谱(UH... 采用基于液质联用的非靶向代谢组学技术结合化学计量学数据自动解析软件AntDAS-LCHRMS分析了4种不同干燥处理(冻干、热泵烘干、电热烘干、晒干)杜仲叶样本中的化合物。杜仲叶样本数据由超高效液相色谱-四极杆-静电场轨道阱高分辨质谱(UHPLC-Q-Exactive Orbitrap HRMS)分别在正、负离子模式下进行采集,经AntDAS-LCHRMS软件解析,共鉴定出71种差异性化合物,经标准品验证确定40种化合物,包括环烯醚萜类、有机酸类、黄酮类、氨基酸类、核苷类、维生素类等9类物质。其中,正、负离子模式下均可识别并验证的化合物有车叶草苷、绿原酸、芦丁、异槲皮苷、车叶草苷酸、京尼平苷等25种化合物。层次聚类分析(HCA)及主成分分析(PCA)结果均显示,相同处理的杜仲叶样本各自聚成一类,不同处理的杜仲叶样本可明显区分。热图分析进一步揭示了不同干燥处理杜仲叶样本中差异性化合物的含量变化。晒干处理样本中苯丙氨酸及色氨酸等氨基酸类物质的水平较高;冻干及热泵烘干处理样本中有机酸类、环烯醚萜类、糖类等含量较高;电热烘干样本中核苷类、黄酮类物质的含量较高;黄酮类物质在冻干、热泵烘干及晒干样本中差异较小。研究结果为不同干燥处理杜仲叶的成分分析、品质评价及其开发应用提供了科学依据,也可为其他复杂药用植物体系的化学成分分析提供参考。 展开更多
关键词 杜仲叶 代谢组学 化学计量学 AntDAS-LChrmS软件 超高效液相色谱-四极杆-静电场轨道阱高分辨质谱(UHPLC-Q-Exactive Orbitrap hrmS) 干燥处理
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基于UHPLC-Orbitrap HRMS的盐酸二甲双胍及其片剂中N-亚硝基二甲胺的测定
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作者 吴静芳 李玮玲 《广州化工》 CAS 2024年第16期77-79,111,共4页
建立了测定盐酸二甲双胍及其片剂中N-亚硝基二甲胺(NDMA)的超高效液相色谱-静电场轨道阱高分辨质谱法(UHPLC-Orbitrap HRMS)。采用Waters XSelect CSH C18色谱柱(150 mm×3.0 mm,2.5μm),以0.1%甲酸水溶液-0.1%甲酸甲醇溶液为流动相... 建立了测定盐酸二甲双胍及其片剂中N-亚硝基二甲胺(NDMA)的超高效液相色谱-静电场轨道阱高分辨质谱法(UHPLC-Orbitrap HRMS)。采用Waters XSelect CSH C18色谱柱(150 mm×3.0 mm,2.5μm),以0.1%甲酸水溶液-0.1%甲酸甲醇溶液为流动相,梯度洗脱;大气压化学电离源(APCI),正离子模式,产物离子扫描。结果显示NDMA在1~100 ng/mL范围内线性关系良好,检测限和定量限分别为0.3 ng/mL和0.9 ng/mL,原料药和片剂的平均加标回收率分别为101.4%和98.5%。本方法专属性好、灵敏度和准确度高,适用于盐酸二甲双胍及其片剂中痕量遗传毒性杂质NDMA的检查与控制。 展开更多
关键词 UHPLC-Orbitrap hrmS N-亚硝基二甲胺 遗传毒性杂质 盐酸二甲双胍
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平台化HRM对组织适应性绩效的影响研究——有调节的双中介模型
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作者 刘翔宇 郑迁 《领导科学》 北大核心 2024年第3期31-37,共7页
基于动态能力理论,借鉴双元观理念,遵循“资源组合—动态能力—组织绩效”的研究范式,构建有调节的双中介模型。经分析可以发现:平台化HRM正向影响组织适应性绩效;技能柔性能力(技能延展性/技能多样性)在平台化HRM与组织适应性绩效之间... 基于动态能力理论,借鉴双元观理念,遵循“资源组合—动态能力—组织绩效”的研究范式,构建有调节的双中介模型。经分析可以发现:平台化HRM正向影响组织适应性绩效;技能柔性能力(技能延展性/技能多样性)在平台化HRM与组织适应性绩效之间起到双重中介作用;前瞻性战略正向调节平台化HRM与技能柔性能力(技能延展性/技能多样性)的关系,即存在有调节的双中介效应。 展开更多
关键词 平台化hrm 组织适应性绩效 技能柔性能力 前瞻性战略
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高职院校HRM数字化育人举措探析
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作者 马远 《市场周刊》 2024年第10期165-169,共5页
在数字化时代,数字化人才已经成为企业数字化转型的关键因素,对企业高质量发展产生重要影响。文章在分析数字化人才分类、培养高职院校HRM数字化人才存在的问题的基础上,提出高职院校HRM数字化人才培养的针对性策略:制订HRM数字化人才... 在数字化时代,数字化人才已经成为企业数字化转型的关键因素,对企业高质量发展产生重要影响。文章在分析数字化人才分类、培养高职院校HRM数字化人才存在的问题的基础上,提出高职院校HRM数字化人才培养的针对性策略:制订HRM数字化人才培养目标,构建数字化人才培养课程体系;注重加强学生数字化思维的培养,提高学生的数字化素养;搭建信息化教学平台;打造跨学科数字化师资队伍;开发高质量的数字化教学资源;建设良好的数字化校外实训教学基地。以期为我国数字化人才培养提供一些新思路、新举措。 展开更多
关键词 高职院校 hrm数字化人才 育人 举措
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基于UPLC-Q-Orbitrap HRMS及GC-MS结合网络药理学和分子对接的彝药黑根抗类风湿性关节炎的药效物质研究
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作者 赵倩 樊锦雅 古锐 《中药与临床》 2024年第3期52-60,共9页
目的:探讨彝药黑根治疗类风湿性关节炎潜在的作用机制以及主要活性成分。方法:运用UPLC-Q-Orbitrap HRMS及GC-MS技术分析黑根的化学成分,利用Swiss Target进行活性成分的靶点筛选和预测,同时在Genecard、OMIM、Dis Ge NET等数据库中筛... 目的:探讨彝药黑根治疗类风湿性关节炎潜在的作用机制以及主要活性成分。方法:运用UPLC-Q-Orbitrap HRMS及GC-MS技术分析黑根的化学成分,利用Swiss Target进行活性成分的靶点筛选和预测,同时在Genecard、OMIM、Dis Ge NET等数据库中筛选类风湿性关节炎相关靶点,利用Cytoscape3.9.0软件构建“活性成分-靶点”网络模型,运用String数据分析平台进行蛋白互作网络分析,并且利用基因富集分析在线工具对核心靶点进行GO富集分析和KEGG通路分析,最后使用分子对接对网络药理学内容进行初步验证。结果:共鉴定出黑根化学成分78个,筛选后活性成分50个,237个潜在作用靶点与类风湿性关节炎相关,包括STAT3、AKT1、EGFR等关键靶点。通路富集分析PI3K-Akt通路、JAK-STAT等信号通路可能是黑根发挥抗类风湿性关节炎的主要途径。通过分子对接技术得出主要活性成分(异绿原酸B、异绿原酸C)与关键靶点有较好结合力。结论:研究初步表明黑根通过多成分、多靶点、多途径治疗类风湿性关节炎的作用,为后续黑根物质基础研究提供了理论依据。 展开更多
关键词 黑根 超高效液相色谱-四极杆/静电场轨道阱高分辨质谱 网络药理学 分子对接 类风湿性关节炎
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UHPLC Q-Exactive Plus Orbitrap HRMS法鉴定隔山消提取物在功能性消化不良大鼠体内代谢产物
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作者 吴宗芹 勾健 +3 位作者 李勇军 陆苑 冉巧巧 孙佳 《中成药》 CAS CSCD 北大核心 2024年第9期2876-2884,共9页
目的建立UHPLC Q-Exactive Plus Orbitrap HRMS法鉴定隔山消提取物在功能性消化不良大鼠体内代谢产物。方法建立功能性消化不良大鼠模型。分析采用Hypersi 1 GOLD C_(18)色谱柱(2.1 mm×100 mm,1.9μm);流动相水(含0.1%甲酸)-乙腈(... 目的建立UHPLC Q-Exactive Plus Orbitrap HRMS法鉴定隔山消提取物在功能性消化不良大鼠体内代谢产物。方法建立功能性消化不良大鼠模型。分析采用Hypersi 1 GOLD C_(18)色谱柱(2.1 mm×100 mm,1.9μm);流动相水(含0.1%甲酸)-乙腈(含0.1%甲酸),梯度洗脱;体积流量0.3 mL/min;柱温40℃;电喷雾离子源;正负离子扫描。结果共鉴定出4种原型成分(白首乌二苯酮、去酰基萝藦苷元、青阳参苷元、丁香酸)及其110种代谢产物,其中粪便、尿液共有代谢产物12种,尿液特有代谢产物56种,粪便特有代谢产物42种。原型成分代谢途径包括Ⅰ相代谢(氧化、还原等)、Ⅱ相代谢(硫酸化、葡萄糖醛酸化等)及Ⅰ相、Ⅱ相复合反应。结论该方法高效全面,可为进一步寻找隔山消潜在活性代谢产物奠定基础。 展开更多
关键词 隔山消提取物 代谢产物 功能性消化不良 UHPLC Q-Exactive Plus Orbitrap hrmS
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基于UHPLC-Q-Orbitrap HRMS雀嘴茶醇提液的成分及活性研究 被引量:1
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作者 王文博 袁甜甜 +6 位作者 吕玉秀 刘桢 谢东 张璟雯 赵平 陈保森 杨晓琴 《西南林业大学学报(自然科学)》 CAS 北大核心 2024年第1期176-184,共9页
基于超高效液相色谱串联四级杆/静电场轨道阱高分辨质谱快速分析雀嘴茶醇提液的成分,对其体外抗氧化活性和酪氨酸酶抑制活性进行研究。结果表明:从雀嘴茶醇提液中鉴定出1 321个代谢物,其中有1 085个代谢物包括11个超类匹配到人类代谢数... 基于超高效液相色谱串联四级杆/静电场轨道阱高分辨质谱快速分析雀嘴茶醇提液的成分,对其体外抗氧化活性和酪氨酸酶抑制活性进行研究。结果表明:从雀嘴茶醇提液中鉴定出1 321个代谢物,其中有1 085个代谢物包括11个超类匹配到人类代谢数据库中,含量较高的活性代谢物,包括新甘草苷、扁蓄苷、醋硝香豆素、槲皮素-3-O-葡萄糖苷桂皮鞣质B1等苯丙素类和芳香聚酮类、咖啡因等有机杂环化合物类、阿糖腺苷等核苷酸及其衍生物以及1-咖啡酰-β-D-葡萄糖、3-O-阿魏酰奎尼酸、绿原酸、2-O-咖啡酰熊果苷等咖啡酰类。雀嘴茶醇提液的DPPH·清除率可达93.56%,ABTS^(+)·清除率可达99.04%,OH·清除率可达94.82%,总还原能力随着醇提液中总多酚浓度的增加而升高且效果极为接近阳性对照抗坏血酸;对酪氨酸酶单酚酶和二酚酶的抑制率分别可达81.50%和58.58%。 展开更多
关键词 雀嘴茶 醇提液 静电场轨道阱高分辨质谱 抗氧化 酪氨酸酶 活性代谢物
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基于UPLC-Q-Orbitrap HRMS代谢组学和16S rRNA基因测序探讨骨疏丹补肾机制
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作者 佟琳 冯啟圣 +4 位作者 张静 陆晴 石伟 赵龙山 熊志立 《沈阳药科大学学报》 CAS CSCD 2024年第6期675-685,698,共12页
目的 整合代谢组学和肠道微生物组学的研究策略探讨骨疏丹(Gushudan, GSD)预防氢化可的松诱导的肾阳虚证(kidney-yang deficiency syndrome, KYDS)大鼠的补肾作用机制。方法 分别采用超高效液相色谱-四级杆/静电场轨道阱高分辨质谱(UPLC... 目的 整合代谢组学和肠道微生物组学的研究策略探讨骨疏丹(Gushudan, GSD)预防氢化可的松诱导的肾阳虚证(kidney-yang deficiency syndrome, KYDS)大鼠的补肾作用机制。方法 分别采用超高效液相色谱-四级杆/静电场轨道阱高分辨质谱(UPLC-Q-Orbitrap HRMS)的非靶向代谢组学和16S rRNA基因测序分析的肠道微生物组学方法,分析正常对照组、肾阳虚证模型组、骨疏丹给药组和阳性对照组大鼠粪便代谢物谱与肠道菌群组成,采用Pearson相关分析探讨内源性差异代谢物与差异菌群之间的相关性。结果 基于UPLC-Q-Orbitrap HRMS的代谢组学方法在正负离子模式下共发现骨疏丹参与调控肾阳虚症的22种差异代谢物,如色氨酸、鹅去氧胆酸、肌酐和油酸酰胺等,主要涉及氨基酸代谢、胆汁酸代谢、能量代谢和脂质代谢。基于16S rRNA测序分析发现骨疏丹在属水平显著上调普雷沃氏菌(Prevotellaceae)的相对丰度(P<0.05),显著下调颤杆菌(Oscillibacter)的相对丰度(P<0.05)。相关性分析结果表明甘胆酸和鹅去氧胆酸与在属水平显著改变的普雷沃氏菌(Prevotellaceae)显著正相关(P<0.05),而与考拉杆菌(Phascolarctobacterium)显著负相关(P<0.05)。二十二碳六烯酸与毛螺菌(Lachnospiraceae)显著负相关(P<0.05)。结论 骨疏丹通过良性调节内源性代谢和肠道菌群结构发挥补肾作用,为中药通过肠-肾轴治疗疾病提供新的思路和方法。 展开更多
关键词 肾阳虚证 骨疏丹 代谢组学 肠道菌群 UPLC-Q-Orbitrap hrmS 16S rRNA基因测序
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基于UPLC-Q-Orbitrap-HRMS技术的葛根-丹参药对化学成分分析 被引量:1
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作者 卢洋 邓小惠 +5 位作者 吴梦瑶 陈萱 陈祥雯 杨宇辉 曹纪亮 万丽 《中南药学》 CAS 2024年第9期2380-2386,共7页
目的采用超高效液相色谱-四极杆-静电场轨道阱高分辨质谱(UPLC-Q-Orbitrap-HRMS)技术分别对以水和50%甲醇溶液为溶剂提取的葛根-丹参药对样品进行化学成分分析。方法采用Thermo Scientific Hypersil GOLD C_(18)色谱柱(150 mm×2.1 ... 目的采用超高效液相色谱-四极杆-静电场轨道阱高分辨质谱(UPLC-Q-Orbitrap-HRMS)技术分别对以水和50%甲醇溶液为溶剂提取的葛根-丹参药对样品进行化学成分分析。方法采用Thermo Scientific Hypersil GOLD C_(18)色谱柱(150 mm×2.1 mm,1.9μm),以0.1%甲酸水-0.1%甲酸乙腈溶液为流动相进行梯度洗脱,流速为0.3 mL·min^(-1),柱温为30℃。采用加热电喷雾离子源(H-ESI),正负离子检测模式。结果从水提和50%甲醇醇提样品溶液中均鉴定出104个化合物,其中103个化合物为共有成分,各有1个差异性成分,分别为水提样品中的刺槐苷与50%甲醇醇提样品中的降丹参酮(或其同分异构体)。共鉴定出的105个化合物,包括黄酮类成分36个、苯丙素类成分20个、萜类成分24个和其他类成分25个。结论本研究首次采用UPLC-Q-Orbitrap-HRMS技术对葛根-丹参药对的主要成分进行鉴定,可为葛根-丹参药对的药效成分研究提供科学依据。 展开更多
关键词 葛根-丹参药对 UPLC-Q-Orbitrap-hrmS 化学成分
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基于UPLC-Q-Orbitrap HRMS结合网络药理学探讨半夏泻心汤入血成分及治疗脾虚型溃疡性结肠炎的作用机制
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作者 朱海燕 杨福权 +5 位作者 左秦川 房智彦 黄丽莉 淮文英 王艳秋 张天娥 《天然产物研究与开发》 CAS CSCD 北大核心 2024年第9期1610-1624,共15页
研究通过建立脾虚型溃疡性结肠炎(ulcerative colitis,UC)模型,采用液相芯片对大鼠血清中炎性细胞因子进行高通量检测,同时以HE染色对结肠组织进行炎症分级评分,验证半夏泻心汤(Banxia Xiexin Tang,BXT)对脾虚型UC的药理作用。随后利用... 研究通过建立脾虚型溃疡性结肠炎(ulcerative colitis,UC)模型,采用液相芯片对大鼠血清中炎性细胞因子进行高通量检测,同时以HE染色对结肠组织进行炎症分级评分,验证半夏泻心汤(Banxia Xiexin Tang,BXT)对脾虚型UC的药理作用。随后利用超高效液相色谱-四极杆/静电场轨道阱高分辨质谱(UPLC-Q-Orbitrap HRMS)对BXT入血成分进行分析,并结合网络药理学,探究BXT治疗脾虚型UC的作用机制。结果显示,UC能够增加大鼠血清中细胞因子白细胞介素-1α(interleukin-1α,IL-1α)、白细胞介素-10(interleukin-10,IL-10)、白细胞介素-18(interleukin-18,IL-18)、干扰素-γ(interferon-γ,IFN-γ)、肿瘤坏死因子(tumor necrosis factor-α,TNF-α)表达水平;BXT可降低血清炎性细胞因子含量,且BXT高剂量组(20 g/kg)下降最明显,无明显炎细胞浸润,表明BXT对脾虚型UC具有一定的治疗作用。大鼠血清中发现入血成分共20个;网络药理学筛选出BXT治疗UC相关靶点87个,涉及炎症反应、炎症反应调节、微生物反应等生物过程,参与了IL-17、脂质与动脉粥样硬化、糖尿病并发症中的AGE-RAGE信号通路、TNF等信号通路。综上可知,BXT治疗脾虚型UC可能与抑制肠道炎症、调节肠道微生物及保护肠道屏障等多个途径相关,从而达到治疗UC效果。 展开更多
关键词 半夏泻心汤 脾虚型溃疡性结肠炎 UPLC-Q-Orbitrap hrmS 入血成分 网络药理学 作用机制
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A Review on Sources,Extractions and Analysis Methods of a Sustainable Biomaterial:Tannins 被引量:2
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作者 Antonio Pizzi Marie-Pierre Laborie Zeki Candan 《Journal of Renewable Materials》 EI CAS 2024年第3期397-425,共29页
Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly ... Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly to substitute petroleum-based products.They are a definite class of sustainable materials of the forestry industry.They have been in operation for hundreds of years to manufacture leather and now for a growing number of applications in a variety of other industries,such as wood adhesives,metal coating,pharmaceutical/medical applications and several others.This review presents the main sources,either already or potentially commercial of this forestry by-materials,their industrial and laboratory extraction systems,their systems of analysis with their advantages and drawbacks,be these methods so simple to even appear primitive but nonetheless of proven effectiveness,or very modern and instrumental.It constitutes a basic but essential summary of what is necessary to know of these sustainable materials.In doing so,the review highlights some of the main challenges that remain to be addressed to deliver the quality and economics of tannin supply necessary to fulfill the industrial production requirements for some materials-based uses. 展开更多
关键词 TANNINS FLAVONOIDS SOURCES extraction methods analysis methods
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Drilling-based measuring method for the c-φ parameter of rock and its field application 被引量:3
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作者 Bei Jiang Fenglin Ma +5 位作者 Qi Wang Hongke Gao Dahu Zhai Yusong Deng Chuanjie Xu Liangdi Yao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第1期65-76,共12页
The technology of drilling tests makes it possible to obtain the strength parameter of rock accurately in situ. In this paper, a new rock cutting analysis model that considers the influence of the rock crushing zone(R... The technology of drilling tests makes it possible to obtain the strength parameter of rock accurately in situ. In this paper, a new rock cutting analysis model that considers the influence of the rock crushing zone(RCZ) is built. The formula for an ultimate cutting force is established based on the limit equilibrium principle. The relationship between digital drilling parameters(DDP) and the c-φ parameter(DDP-cφ formula, where c refers to the cohesion and φ refers to the internal friction angle) is derived, and the response of drilling parameters and cutting ratio to the strength parameters is analyzed. The drillingbased measuring method for the c-φ parameter of rock is constructed. The laboratory verification test is then completed, and the difference in results between the drilling test and the compression test is less than 6%. On this basis, in-situ rock drilling tests in a traffic tunnel and a coal mine roadway are carried out, and the strength parameters of the surrounding rock are effectively tested. The average difference ratio of the results is less than 11%, which verifies the effectiveness of the proposed method for obtaining the strength parameters based on digital drilling. This study provides methodological support for field testing of rock strength parameters. 展开更多
关键词 Digital drilling Rock crushing zone c-u parameter Measurement method Field application
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A comparison study on structure-function relationship of polysaccharides obtained from sea buckthorn berries using different methods:antioxidant and bile acid-binding capacity 被引量:5
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作者 Qiaoyun Li Zuman Dou +5 位作者 Qingfei Duan Chun Chen Ruihai Liu Yueming Jiang Bao Yang Xiong Fu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期494-505,共12页
In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic... In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic(HRP-U),acid(HRP-C)and alkali(HRP-A)assisted extraction methods were investigated.The results demonstrated that extraction methods had significant effects on extraction yield,monosaccharide composition,molecular weight,particle size,triple-helical structure,and surface morphology of HRPs except for the major linkage bands.Thermogravimetric analysis showed that HRP-U with filamentous reticular microstructure exhibited better thermal stability.The HRP-A with the lowest molecular weight and highest arabinose content possessed the best antioxidant activities.Moreover,the rheological analysis indicated that HRPs with higher galacturonic acid content and molecular weight showed higher viscosity and stronger crosslinking network(HRP-C,HRP-W and HRP-U),which exhibited stronger bile acid binding capacity.The present findings provide scientific evidence in the preparation technology of sea buckthorn polysaccharides with good antioxidant and bile acid binding capacity which are related to the structure affected by the extraction methods. 展开更多
关键词 Sea buckthorn Extraction method STRUCTURE Rheological properties Antioxidant activity Bile acid binding capacity
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Material point method simulation of hydro-mechanical behaviour in twophase porous geomaterials: A state-of-the-art review 被引量:2
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作者 Xiangcou Zheng Shuying Wang +1 位作者 Feng Yang Junsheng Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2341-2350,共10页
The material point method(MPM)has been gaining increasing popularity as an appropriate approach to the solution of coupled hydro-mechanical problems involving large deformation.In this paper,we survey the current stat... The material point method(MPM)has been gaining increasing popularity as an appropriate approach to the solution of coupled hydro-mechanical problems involving large deformation.In this paper,we survey the current state-of-the-art in the MPM simulation of hydro-mechanical behaviour in two-phase porous geomaterials.The review covers the recent advances and developments in the MPM and their extensions to capture the coupled hydro-mechanical problems involving large deformations.The focus of this review is aiming at providing a clear picture of what has or has not been developed or implemented for simulating two-phase coupled large deformation problems,which will provide some direct reference for both practitioners and researchers. 展开更多
关键词 Coupled problems Hydro-mechanical behaviour Large deformation Material Point method(MPM)
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Volumetric lattice Boltzmann method for pore-scale mass diffusionadvection process in geopolymer porous structures 被引量:1
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作者 Xiaoyu Zhang Zirui Mao +6 位作者 Floyd W.Hilty Yulan Li Agnes Grandjean Robert Montgomery Hans-Conrad zur Loye Huidan Yu Shenyang Hu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2126-2136,共11页
Porous materials present significant advantages for absorbing radioactive isotopes in nuclear waste streams.To improve absorption efficiency in nuclear waste treatment,a thorough understanding of the diffusion-advecti... Porous materials present significant advantages for absorbing radioactive isotopes in nuclear waste streams.To improve absorption efficiency in nuclear waste treatment,a thorough understanding of the diffusion-advection process within porous structures is essential for material design.In this study,we present advancements in the volumetric lattice Boltzmann method(VLBM)for modeling and simulating pore-scale diffusion-advection of radioactive isotopes within geopolymer porous structures.These structures are created using the phase field method(PFM)to precisely control pore architectures.In our VLBM approach,we introduce a concentration field of an isotope seamlessly coupled with the velocity field and solve it by the time evolution of its particle population function.To address the computational intensity inherent in the coupled lattice Boltzmann equations for velocity and concentration fields,we implement graphics processing unit(GPU)parallelization.Validation of the developed model involves examining the flow and diffusion fields in porous structures.Remarkably,good agreement is observed for both the velocity field from VLBM and multiphysics object-oriented simulation environment(MOOSE),and the concentration field from VLBM and the finite difference method(FDM).Furthermore,we investigate the effects of background flow,species diffusivity,and porosity on the diffusion-advection behavior by varying the background flow velocity,diffusion coefficient,and pore volume fraction,respectively.Notably,all three parameters exert an influence on the diffusion-advection process.Increased background flow and diffusivity markedly accelerate the process due to increased advection intensity and enhanced diffusion capability,respectively.Conversely,increasing the porosity has a less significant effect,causing a slight slowdown of the diffusion-advection process due to the expanded pore volume.This comprehensive parametric study provides valuable insights into the kinetics of isotope uptake in porous structures,facilitating the development of porous materials for nuclear waste treatment applications. 展开更多
关键词 Volumetric lattice Boltzmann method(VLBM) Phase field method(PFM) Pore-scale diffusion-advection Nuclear waste treatment Porous media flow Graphics processing unit(GPU) parallelization
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Quantification of Structurally Alert Mutagenic Impurities in Meropenem Trihydrate Drug Substance by Liquid Chromatography with High Resolution Mass Spectrometer (LC-HRMS)
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作者 Anwar Sulaiman K. Ramakrishna Reddy +1 位作者 Vundavilli Jagadeesh Kumar Hemant Kumar Sharma 《American Journal of Analytical Chemistry》 CAS 2024年第3期119-133,共15页
Potential mutagenic impurities in Active Pharmaceutical Ingredient, Meropenem Trihydrate were assessed and a novel analytical method for their quantification was developed and validated. This Liquid Chromatographic me... Potential mutagenic impurities in Active Pharmaceutical Ingredient, Meropenem Trihydrate were assessed and a novel analytical method for their quantification was developed and validated. This Liquid Chromatographic method using High Resolution Mass Spectrometer (LC-HRMS) technique is proved to be suitable for simultaneous quantification of all ten identified impurities with required specificity, sensitivity, resolution, precision, accuracy, and other method characteristics as per ICH Guidelines. The acceptable limit of less than 2.9 μg/g was considered for evaluations, based on drug substance dosage and duration of treatment. The method stands most sensitive with a Limit of Detection of 0.35 μg/g, considering the challenge full acceptance criteria as per current regulatory standards. 展开更多
关键词 Mutagenic Impurities LC-hrmS Meropenem Trihydrate method Validation
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Sparse Modal Decomposition Method Addressing Underdetermined Vortex-Induced Vibration Reconstruction Problem for Marine Risers 被引量:1
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作者 DU Zun-feng ZHU Hai-ming YU Jian-xing 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期285-296,共12页
When investigating the vortex-induced vibration(VIV)of marine risers,extrapolating the dynamic response on the entire length based on limited sensor measurements is a crucial step in both laboratory experiments and fa... When investigating the vortex-induced vibration(VIV)of marine risers,extrapolating the dynamic response on the entire length based on limited sensor measurements is a crucial step in both laboratory experiments and fatigue monitoring of real risers.The problem is conventionally solved using the modal decomposition method,based on the principle that the response can be approximated by a weighted sum of limited vibration modes.However,the method is not valid when the problem is underdetermined,i.e.,the number of unknown mode weights is more than the number of known measurements.This study proposed a sparse modal decomposition method based on the compressed sensing theory and the Compressive Sampling Matching Pursuit(Co Sa MP)algorithm,exploiting the sparsity of VIV in the modal space.In the validation study based on high-order VIV experiment data,the proposed method successfully reconstructed the response using only seven acceleration measurements when the conventional methods failed.A primary advantage of the proposed method is that it offers a completely data-driven approach for the underdetermined VIV reconstruction problem,which is more favorable than existing model-dependent solutions for many practical applications such as riser structural health monitoring. 展开更多
关键词 motion reconstruction vortex-induced vibration(VIV) marine riser modal decomposition method compressed sensing
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Uncertainties of landslide susceptibility prediction: Influences of random errors in landslide conditioning factors and errors reduction by low pass filter method 被引量:1
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作者 Faming Huang Zuokui Teng +4 位作者 Chi Yao Shui-Hua Jiang Filippo Catani Wei Chen Jinsong Huang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期213-230,共18页
In the existing landslide susceptibility prediction(LSP)models,the influences of random errors in landslide conditioning factors on LSP are not considered,instead the original conditioning factors are directly taken a... In the existing landslide susceptibility prediction(LSP)models,the influences of random errors in landslide conditioning factors on LSP are not considered,instead the original conditioning factors are directly taken as the model inputs,which brings uncertainties to LSP results.This study aims to reveal the influence rules of the different proportional random errors in conditioning factors on the LSP un-certainties,and further explore a method which can effectively reduce the random errors in conditioning factors.The original conditioning factors are firstly used to construct original factors-based LSP models,and then different random errors of 5%,10%,15% and 20%are added to these original factors for con-structing relevant errors-based LSP models.Secondly,low-pass filter-based LSP models are constructed by eliminating the random errors using low-pass filter method.Thirdly,the Ruijin County of China with 370 landslides and 16 conditioning factors are used as study case.Three typical machine learning models,i.e.multilayer perceptron(MLP),support vector machine(SVM)and random forest(RF),are selected as LSP models.Finally,the LSP uncertainties are discussed and results show that:(1)The low-pass filter can effectively reduce the random errors in conditioning factors to decrease the LSP uncertainties.(2)With the proportions of random errors increasing from 5%to 20%,the LSP uncertainty increases continuously.(3)The original factors-based models are feasible for LSP in the absence of more accurate conditioning factors.(4)The influence degrees of two uncertainty issues,machine learning models and different proportions of random errors,on the LSP modeling are large and basically the same.(5)The Shapley values effectively explain the internal mechanism of machine learning model predicting landslide sus-ceptibility.In conclusion,greater proportion of random errors in conditioning factors results in higher LSP uncertainty,and low-pass filter can effectively reduce these random errors. 展开更多
关键词 Landslide susceptibility prediction Conditioning factor errors Low-pass filter method Machine learning models Interpretability analysis
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Numerical manifold method for thermo-mechanical coupling simulation of fractured rock mass 被引量:1
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作者 Jiawei Liang Defu Tong +3 位作者 Fei Tan Xiongwei Yi Junpeng Zou Jiahe Lv 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期1977-1992,共16页
As a calculation method based on the Galerkin variation,the numerical manifold method(NMM)adopts a double covering system,which can easily deal with discontinuous deformation problems and has a high calculation accura... As a calculation method based on the Galerkin variation,the numerical manifold method(NMM)adopts a double covering system,which can easily deal with discontinuous deformation problems and has a high calculation accuracy.Aiming at the thermo-mechanical(TM)coupling problem of fractured rock masses,this study uses the NMM to simulate the processes of crack initiation and propagation in a rock mass under the influence of temperature field,deduces related system equations,and proposes a penalty function method to deal with boundary conditions.Numerical examples are employed to confirm the effectiveness and high accuracy of this method.By the thermal stress analysis of a thick-walled cylinder(TWC),the simulation of cracking in the TWC under heating and cooling conditions,and the simulation of thermal cracking of the SwedishÄspöPillar Stability Experiment(APSE)rock column,the thermal stress,and TM coupling are obtained.The numerical simulation results are in good agreement with the test data and other numerical results,thus verifying the effectiveness of the NMM in dealing with thermal stress and crack propagation problems of fractured rock masses. 展开更多
关键词 Heat conduction Fractured rock mass Crack propagation Galerkin variation Numerical manifold method(NMM)
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