Valeriana officinalis L.is a plant from the Caprifoliaceae family,which is widely distributed in various parts of the world,especially in Europe and Asia.All species of Valeriana are distinguished by their ability to s...Valeriana officinalis L.is a plant from the Caprifoliaceae family,which is widely distributed in various parts of the world,especially in Europe and Asia.All species of Valeriana are distinguished by their ability to synthesize essen-tial oil,which has a powerful effect on the physiological and mental aspects of the human body.The aim was to study the qualitative and quantitative composition of essential oil from valerian roots,collected in different coun-tries,using the gas chromatography method,and to establish marker compounds for valerian species.13 samples of commercial roots with rhizomes of V.officinalis from nine countries of the world and a sample of Valeriana pratensis and Valeriana stolonifera growing in Ukraine were selected for the study.The essential oil was obtained from dried valerian roots by the distillation method described in the European Pharmacopoeia.To determine the component composition of the essential oils of the selected samples,the methods of gas chromatography with a mass spectrometric detector and capillary gas chromatography were used.The commercial samples of V.offici-nalis from different countries yielded 0.21%–1.03%of essential oil.Only six of 13 samples contained essential oil in an amount that satisfies the requirement of the European Pharmacopoeia standard(not less than 4 mL/kg).150 compounds were identified in the essential oils of 13 samples of V.officinalis essential oils.The range and average content and coefficients of variation of the identified compounds were determined.The principal com-pounds of V.officinalis essential oils were bornyl acetate(1.6%–27.1%),valeranone(0.5%–17.9%),valerenal(0%–14.7%),camphene(0%–14.6%),α-fenchene(0%–10.6%),and valerenic acid(0%–8.5%).The samples of V.pratensis and V.stolonifera yielded rather high levels of essential oil(1.18%and 0.93%,respectively).Three chemotypes of V.officinalis samples were determined-bornyl acetate/valerenal,valeranone,and isovaleric acid.The composition of the three essential oils compared was rather similar.Based on the study results,we propose the following marker compounds for V.officinalis consistently present in all 16 examined samples:bornyl acetate(1.6%–27.1%),limonene(0.2–2.3),and valeranone(0.5%–17.9%).The study of samples from Ukraine indicates the prospects of using these species of the genus Valeriana with the aim of expanding the raw material base and creating potential herbal preparations with a sedative effect,which are extremely necessary for the population of the country in the war and post-war periods.展开更多
L波段数字航空通信系统(L band digital aeronautical communication system,LDACS)是未来航空宽带通信重要的基础设施之一,针对LDACS信号容易受到相邻波道大功率测距仪(distance measuring equipment,DME)信号干扰的问题,提出了联合正...L波段数字航空通信系统(L band digital aeronautical communication system,LDACS)是未来航空宽带通信重要的基础设施之一,针对LDACS信号容易受到相邻波道大功率测距仪(distance measuring equipment,DME)信号干扰的问题,提出了联合正交投影干扰抑制与单快拍稀疏分解的波达方向(direction of arrival,DOA)估计方法。通过子空间投影抑制DME干扰,然后使用单快拍数据构建伪协方差矩阵,对伪协方差矩阵求高阶幂,之后进行奇异值分解,并利用约束条件求解稀疏解得到期望信号来向的估计值。所提方法使用高阶伪协方差矩阵降低了噪声影响,仅用单快拍就可以准确估计LDACS信号的入射方向。仿真结果表明,改进单快拍高级幂(improved single snapshot high order power,ISS-HOP)L1-SVD算法的估计精度优于ISS-HOP-MUSIC算法。该方法可以有效抑制DME干扰,提高OFDM接收机性能。展开更多
针对L波段数字航空通信系统(L-band digital aeronautic communication system,LDACS)可用频谱资源有限且易受大功率测距仪(distance measuring equipment,DME)信号干扰的问题,提出一种基于降维循环谱和残差神经网络的频谱感知方法。首...针对L波段数字航空通信系统(L-band digital aeronautic communication system,LDACS)可用频谱资源有限且易受大功率测距仪(distance measuring equipment,DME)信号干扰的问题,提出一种基于降维循环谱和残差神经网络的频谱感知方法。首先理论推导分析了DME信号的循环谱特征;然后利用Fisher判别率(Fisher discriminant rate,FDR)提取循环频率能量最大的向量,通过主成分分析(principal component analysis,PCA)进行预处理特征增强;最后给出数据处理后的循环谱向量与卷积神经网络相结合的实现过程,实现了DME信号的有效检测。仿真结果表明,该方法对噪声不敏感,当信噪比不低于-15 dB时,平均检测概率大于90%。当信噪比不低于-14 dB,检测概率接近100%。展开更多
基金supported by the European Union in the MSCA4Ukraine Project“Design and Development of 3D-Printed Medicines for Bioactive Materials of Ukrainian and Estonian Medicinal Plants Origin”(ID Number 1232466).
文摘Valeriana officinalis L.is a plant from the Caprifoliaceae family,which is widely distributed in various parts of the world,especially in Europe and Asia.All species of Valeriana are distinguished by their ability to synthesize essen-tial oil,which has a powerful effect on the physiological and mental aspects of the human body.The aim was to study the qualitative and quantitative composition of essential oil from valerian roots,collected in different coun-tries,using the gas chromatography method,and to establish marker compounds for valerian species.13 samples of commercial roots with rhizomes of V.officinalis from nine countries of the world and a sample of Valeriana pratensis and Valeriana stolonifera growing in Ukraine were selected for the study.The essential oil was obtained from dried valerian roots by the distillation method described in the European Pharmacopoeia.To determine the component composition of the essential oils of the selected samples,the methods of gas chromatography with a mass spectrometric detector and capillary gas chromatography were used.The commercial samples of V.offici-nalis from different countries yielded 0.21%–1.03%of essential oil.Only six of 13 samples contained essential oil in an amount that satisfies the requirement of the European Pharmacopoeia standard(not less than 4 mL/kg).150 compounds were identified in the essential oils of 13 samples of V.officinalis essential oils.The range and average content and coefficients of variation of the identified compounds were determined.The principal com-pounds of V.officinalis essential oils were bornyl acetate(1.6%–27.1%),valeranone(0.5%–17.9%),valerenal(0%–14.7%),camphene(0%–14.6%),α-fenchene(0%–10.6%),and valerenic acid(0%–8.5%).The samples of V.pratensis and V.stolonifera yielded rather high levels of essential oil(1.18%and 0.93%,respectively).Three chemotypes of V.officinalis samples were determined-bornyl acetate/valerenal,valeranone,and isovaleric acid.The composition of the three essential oils compared was rather similar.Based on the study results,we propose the following marker compounds for V.officinalis consistently present in all 16 examined samples:bornyl acetate(1.6%–27.1%),limonene(0.2–2.3),and valeranone(0.5%–17.9%).The study of samples from Ukraine indicates the prospects of using these species of the genus Valeriana with the aim of expanding the raw material base and creating potential herbal preparations with a sedative effect,which are extremely necessary for the population of the country in the war and post-war periods.
文摘L波段数字航空通信系统(L band digital aeronautical communication system,LDACS)是未来航空宽带通信重要的基础设施之一,针对LDACS信号容易受到相邻波道大功率测距仪(distance measuring equipment,DME)信号干扰的问题,提出了联合正交投影干扰抑制与单快拍稀疏分解的波达方向(direction of arrival,DOA)估计方法。通过子空间投影抑制DME干扰,然后使用单快拍数据构建伪协方差矩阵,对伪协方差矩阵求高阶幂,之后进行奇异值分解,并利用约束条件求解稀疏解得到期望信号来向的估计值。所提方法使用高阶伪协方差矩阵降低了噪声影响,仅用单快拍就可以准确估计LDACS信号的入射方向。仿真结果表明,改进单快拍高级幂(improved single snapshot high order power,ISS-HOP)L1-SVD算法的估计精度优于ISS-HOP-MUSIC算法。该方法可以有效抑制DME干扰,提高OFDM接收机性能。
