粘结型Nd Fe B永磁体具有组织疏松、孔隙率高、强度低、耐热性差等特点。试验了孔隙封闭、除毛刺、边角滚光及活化除去基体氧化膜等前处理技术。研究化学镀Ni P工艺,选择一次性化学镀Ni P合金工艺,成功地解决了Nd Fe B永磁体的防腐技... 粘结型Nd Fe B永磁体具有组织疏松、孔隙率高、强度低、耐热性差等特点。试验了孔隙封闭、除毛刺、边角滚光及活化除去基体氧化膜等前处理技术。研究化学镀Ni P工艺,选择一次性化学镀Ni P合金工艺,成功地解决了Nd Fe B永磁体的防腐技术问题。既简化了工艺流程,缩短了施镀时间,又降低了成本。本工艺亦适合烧结型Nd Fe B永磁体的防腐。展开更多
The B-meson decay constant fB is an important component for studying the B-meson decays, which can be studied through QCD sum rules. We make a detailed discussion on f B from two sum rules up to next-to- leading order...The B-meson decay constant fB is an important component for studying the B-meson decays, which can be studied through QCD sum rules. We make a detailed discussion on f B from two sum rules up to next-to- leading order, i.e. sum rules I and II, which are derived from the conventional correlator and the correlator with chiral currents respectively. It is found that these two sum rules are consistent with each other. The sum rules H involves less non-perturbative condensates as that of sum rules I, and in principle, it can be more accurate if we know the dimensionfour gluon condensate well. It is found that fB decreases with the increment of mb, and to compare with the Belle experimental data on fB, both sum rules I and H prefer smaller pole b-quark mass, mb= 4.68 ± 0.07 GeV. By varying all the input parameters within their reasonable regions and by adding all the uncertainties in quadrature, we obtain fB=172-25^＋23 MeV for sum rules I and fB =214-34^26 MeV for sum rules П.展开更多
本研究旨在探讨灵香草提取物中的主要活性成分Foenumoside B (FB)与有氧运动(AE)协同对高脂血症大鼠肝脏脂质代谢紊乱的影响。通过建立高脂饮食诱导的高脂血症大鼠模型,将大鼠随机分为对照组、HLP组、AE组、FB组和FB+AE联合组,通过实验...本研究旨在探讨灵香草提取物中的主要活性成分Foenumoside B (FB)与有氧运动(AE)协同对高脂血症大鼠肝脏脂质代谢紊乱的影响。通过建立高脂饮食诱导的高脂血症大鼠模型,将大鼠随机分为对照组、HLP组、AE组、FB组和FB+AE联合组,通过实验观察各组大鼠的血脂水平、肝脏脂质代谢相关基因表达以及肝脏组织病理变化。结果表明,与单独使用FB或AE相比,FB与AE的联合干预能更有效地降低血脂水平,调节ACAT1、DGAT2、FAS、SREBP1c、PPARα、LCAT、UCP2、MCD和CPT-1等脂质代谢相关基因的表达,减轻肝脏脂质积累和损伤。本研究证实了FB与AE的协同干预对改善HLP大鼠的脂质代谢紊乱具有显著效果,为开发新型的HLP治疗策略提供了科学依据。展开更多
目的 建立灵香草Lysimachia foenum-graecum一测多评法(quantitative analysis of multi-components by single marker,QAMS)多指标成分定量控制方法,采用多元统计分析模型评价不同产地灵香草质量差异。方法 以Prep Scalar C18柱为色谱...目的 建立灵香草Lysimachia foenum-graecum一测多评法(quantitative analysis of multi-components by single marker,QAMS)多指标成分定量控制方法,采用多元统计分析模型评价不同产地灵香草质量差异。方法 以Prep Scalar C18柱为色谱柱,乙腈-0.2%磷酸为流动相(梯度洗脱),以槲皮素和熊果酸为内参物,采用QAMS法同时测定灵香草中绿原酸、杨梅素、槲皮素、山柰酚、foenumoside B、零陵香皂苷C、齐墩果酸、熊果酸、豆甾醇和β-谷甾醇含量,同时用外标法验证QAMS法的准确性。依据《中国药典》检测浸出物、总灰分和酸不溶性灰分。进一步应用主成分分析(principal component analysis,PCA)、因子分析(factor analysis,FA)和正交偏最小二乘法判别分析(orthogonal partial least squares discriminant analysis,OPLS-DA)法对15批不同产地的灵香草进行区分比较,寻找差异因子。结果 建立的相对校正因子可用于定量分析,且耐用性良好;QAMS法与外标法结果无显著差异,但各批次间差异较大。PCA结果显示15批灵香草聚为3类,FA结果显示广东和广西产地的灵香草质量较优,OPLS-DA结果显示foenumoside B、山柰酚、零陵香皂苷C、绿原酸、槲皮素和豆甾醇是影响灵香草产品质量的差异性标志物。结论 基于多指标成分定量、多元统计分析评价灵香草质量的方法,为灵香草质量标准统一和提升提供基础资料。展开更多
文摘 粘结型Nd Fe B永磁体具有组织疏松、孔隙率高、强度低、耐热性差等特点。试验了孔隙封闭、除毛刺、边角滚光及活化除去基体氧化膜等前处理技术。研究化学镀Ni P工艺,选择一次性化学镀Ni P合金工艺,成功地解决了Nd Fe B永磁体的防腐技术问题。既简化了工艺流程,缩短了施镀时间,又降低了成本。本工艺亦适合烧结型Nd Fe B永磁体的防腐。
基金Supported by Natural Science Foundation Project of CQ CSTC under Grant No.2008BB0298by Natural Science Foundation of China under Grant Nos.10805082 and 11075225by the Fundamental Research Funds for the Central Universities under Grant No.CDJZR101000616
文摘The B-meson decay constant fB is an important component for studying the B-meson decays, which can be studied through QCD sum rules. We make a detailed discussion on f B from two sum rules up to next-to- leading order, i.e. sum rules I and II, which are derived from the conventional correlator and the correlator with chiral currents respectively. It is found that these two sum rules are consistent with each other. The sum rules H involves less non-perturbative condensates as that of sum rules I, and in principle, it can be more accurate if we know the dimensionfour gluon condensate well. It is found that fB decreases with the increment of mb, and to compare with the Belle experimental data on fB, both sum rules I and H prefer smaller pole b-quark mass, mb= 4.68 ± 0.07 GeV. By varying all the input parameters within their reasonable regions and by adding all the uncertainties in quadrature, we obtain fB=172-25^＋23 MeV for sum rules I and fB =214-34^26 MeV for sum rules П.
文摘本研究旨在探讨灵香草提取物中的主要活性成分Foenumoside B (FB)与有氧运动(AE)协同对高脂血症大鼠肝脏脂质代谢紊乱的影响。通过建立高脂饮食诱导的高脂血症大鼠模型,将大鼠随机分为对照组、HLP组、AE组、FB组和FB+AE联合组,通过实验观察各组大鼠的血脂水平、肝脏脂质代谢相关基因表达以及肝脏组织病理变化。结果表明,与单独使用FB或AE相比,FB与AE的联合干预能更有效地降低血脂水平,调节ACAT1、DGAT2、FAS、SREBP1c、PPARα、LCAT、UCP2、MCD和CPT-1等脂质代谢相关基因的表达,减轻肝脏脂质积累和损伤。本研究证实了FB与AE的协同干预对改善HLP大鼠的脂质代谢紊乱具有显著效果,为开发新型的HLP治疗策略提供了科学依据。
