检索结果-南通市图书馆

柴胡-白芍药对配方颗粒指纹图谱的建立及多指标性成分含量测定

在线全文

学校读者我要写书评

暂无评论

天然产物研究与开发 2024年第4期36卷 572-580页

作者：杨新雪梁进京董蕊吉林农业大学中药材学院长春130118

建立柴胡-白芍药对配方颗粒的HPLC指纹图谱、化学模式识别及多指标成分含量测定方法。采用COSMOSIL 5C_(18)-MS-Ⅱ(250 mm×4.6 mm, 5μm)色谱柱;乙腈-0.1%磷酸水为流动相,梯度洗脱;体积流量1.0 mL/min;检测波长分别为210、230 nm;柱温3... 详细信息

建立柴胡-白芍药对配方颗粒的HPLC指纹图谱、化学模式识别及多指标成分含量测定方法。采用COSMOSIL 5C_(18)-MS-Ⅱ(250 mm×4.6 mm, 5μm)色谱柱;乙腈-0.1%磷酸水为流动相,梯度洗脱;体积流量1.0 mL/min;检测波长分别为210、230 nm;柱温30℃。建立HPLC指纹图谱,利用相似度评价、聚类分析(clustering analysis, CA)以及主成分分析(principal component analysis, PCA)对15批柴胡-白芍药对配方颗粒指纹图谱进行研究,同时测定4种指标性成分含量。本研究建立的指纹图谱共确定15个共有峰,并指认了其中的4种成分;15批柴胡-白芍药对配方颗粒指纹图谱与对照指纹图谱的相似度均>0.90;CA和PCA均可将15批柴胡-白芍药对配方颗粒大致分为2类;多指标成分含量测定方法符合方法学考察要求,4种成分的含量均有不同程度的差异。所建方法简单易行,可为柴胡-白芍药对配方颗粒的质量控制和临床用药提供参考。

关键词：柴胡-白芍配方颗粒指纹图谱化学模式识别含量测定

Forecasting water disaster for a coal mine under the Xiaolangdi reservoir

在线全文

学校读者我要写书评

暂无评论

Journal of China University of Mining and Technology 2008年第4期18卷 516-520页

作者： SUN Ya-jun XU Zhi-min dong Qing-hong LIU Sheng-dong GAO Rong-bin JIANG Yu-hai School of Resource and Geoscience China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China Yima Coal Industry Group Yima Henan 472300 China

Xin’an coal mine, Henan Province, faces the risk of water inrush because 40% of the area of the coal mine is under the surface water of the Xiaolangdi reservoir. To forecast water disaster, an effective aquifuge and a limit of water infiltration were determined by rock-phase analysis and long term observations of surface water and groundwater. By field monitoring, as well as physical and numerical simulation experiments, we obtained data reflecting different heights of a water flow fractured zone (WFFZ) under different mining conditions, derived a formula to calculate this height and built a forecasting model with the aid of GIS. On the basis of these activities, the coal mine area was classified into three sub-areas with different potential of water inrush. In the end, our research results have been applied in and verified by industrial mining experiments at three working faces and we were able to present a successful example of coal mining under a large reservoir.

关键词： coal mining under surface water water flow fractured zone water inrush of coal mine effective aquifuge forecasting model

Effect of pre-oxidation degree on gaseous reduction of pre-oxidized ilmenite concentrate by CO

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2022年第6期29卷 881-890页

作者： shi-qing Zhao Xiao-dong Lv Zhi-ming Yan Xue-wei Lv Wei Lv Chen-guang Bai College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Advanced Manufacturing&Materials Centre University of WarwickCoventry CV47ALUK School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

The effect of pre-oxidation degree of Panzhihua ilmenite concentrate on the gaseous reduction by carbon monoxide was *** raw ilmenite concentrates were pre-oxidized at 600,700,800,900,and 1000°C for 2 h,*** phase change,FeO content,and morphology after the oxidation at various temperatures were *** oxidation degree was calculated according to the change of FeO *** was performed on the oxidized ilmenite concentrate samples(oxidized at 600,800,and 1000°C)at 850,900,and 950°C,*** results show that the pre-oxidation of ilmenite concentrate can accelerate the reduction process:the higher pre-oxidation degree,the faster reduction *** high pre-oxidation degree of ilmenite concentrate is beneficial to accelerate the subsequent reduction process in two *** stages of the reduction process were divided via the first derivatives of reduction degree,and the reduction mechanism and apparent activation energy were discussed subsequently.

关键词： Ilmenite Pre-oxidation Reduction Kinetic Titanium slag

"8"字钢板临时骨骺阻滞技术治疗儿童双下肢不等长

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中华骨科杂志 2024年第9期44卷 601-608页

作者：董轶非徐雷闫桂森杨征首都医科大学附属北京积水潭医院国家骨科医学中心北京100035

目的探讨"8"字钢板临时骨骺阻滞技术治疗儿童双下肢不等长的阻滞效果。方法回顾性分析2013年1月至2020年7月北京积水潭医院小儿骨科采用"8"字钢板治疗的双下肢不等长患儿49例,男27例、女22例,手术时年龄为(8.8±2.6)岁(范围3.8~13.1岁)... 详细信息

目的探讨"8"字钢板临时骨骺阻滞技术治疗儿童双下肢不等长的阻滞效果。方法回顾性分析2013年1月至2020年7月北京积水潭医院小儿骨科采用"8"字钢板治疗的双下肢不等长患儿49例,男27例、女22例,手术时年龄为(8.8±2.6)岁(范围3.8~13.1岁)。术前通过下肢全长X线片测量股骨和胫骨的长度差异,应用"8"字钢板在较长腿的股骨远端和(或)胫骨近端骺板内、外侧分别跨骨骺固定以减速生长。随访中于膝关节正侧位X线片评估局部骺板形态及内固定情况,双下肢全长X线片对比手术前后股骨、胫骨长度差变化,以评估阻滞手术效果;并按照阻滞部位(股骨或胫骨)、病因(不等长差距恒定或增加)、阻滞螺钉直径(3.5或4.5 mm)以及阻滞时年龄(≥8岁或<8岁)进行分组,对比阻滞速率的差异。结果49例均顺利完成手术,随访时间为(39.6±18.5)个月(范围16~91个月),钢板固定时间为(24.3±11.8)个月(范围7~66个月)。共获得76个独立的单骨阻滞数据资料,阻滞幅度为(8.6±6.4)mm(范围-8~37 mm)。76个单骨阻滞速率为(0.35±0.31)mm/月,其中52个股骨的阻滞速率为(0.41±0.32)mm/月,较24个胫骨的(0.20±0.14)mm/月长,差异有统计学意义(t=5.323,P=0.008);双下肢不等长差距恒定组阻滞速率为(0.54±0.32)mm/月,较双下肢不等长差距增加组的(0.26±0.21)mm/月长,差异有统计学意义(t=7.362,P=0.001);直径4.5 mm螺钉组阻滞速率为(0.46±0.23)mm/月,较直径3.5 mm螺钉组的(0.26±0.24)mm/月长,差异有统计学意义(t=3.467,P=0.022);<8岁组30骨阻滞速率(0.32±0.25)mm/月、≥8岁组46骨为(0.37±0.31)mm/月,差异无统计学意义(t=1.026,P=0.548)。结论"8"字钢板临时骨骺阻滞技术治疗双下肢不等长的阻滞效果与原始病因及阻滞部位有关,股骨远端阻滞效果优于胫骨近端,双下肢不等长差距恒定者阻滞效果优于差距增加者,应用较粗的螺钉效果更好。由于阻滞效果较缓慢,应当早期治疗、合理选择适应证以获得更佳阻滞效果。

关键词：儿童内固定器骨骺双下肢不等长

Equation of state for boron nitride along the principal Hugoniot to 16 Mbar

在线全文

学校读者我要写书评

暂无评论

Matter and Radiation at Extremes 2024年第5期9卷 77-86页

作者： Huan Zhang Yutong Yang Weimin Yang Zanyang Guan Xiaoxi Duan Mengsheng Yang Yonggang Liu Jingxiang Shen Katarzyna Batani Diluka Singappuli Ke Lan Yongsheng Li Wenyi Huo Hao Liu Yulong Li dong Yang Sanwei Li Zhebin Wang Jiamin Yang Zongqing Zhao Weiyan Zhang Liang Sun Wei Kang Dimitri Batani National Key Laboratory of Plasma Physics Laser Fusion Research CenterChina Academy of Engineering PhysicsMianyang 621900China HEDPS Center for Applied Physics and Technologyand College of PhysicsPeking UniversityBeijing 100871China HEDPS Center for Applied Physics and Technologyand School of EngineeringPeking UniversityBeijing 100871China Institute of Plasma Physics and Laser Microfusion Hery 2301-497 WarszawaPoland Universitéde Bordeaux CNRSCEACELIA(Centre Lasers Intenses et Applications)UMR 5107F-33405 TalenceFrance Institute of Applied Physics and Computational Mathematics Beijing 100094China

The thermodynamic properties of boron nitride under extreme pressures and temperatures are of great interest and importance for materials science and inertial confinement fusion physics,but they are poorly understood owing to the challenges of performing experiments and realizing ab initio ***,we report the first shock Hugoniot data on hexagonal boron nitride at pressures of 5–16 Mbar,using hohlraum-driven shock waves at the SGIII-p laser facility in *** density functional theory molecular dynamics calculations closely match experimental data,validating the equations of state for modeling the shock response of boron nitride and filling a crucial gap in the knowledge of boron nitride properties in the region of multi-Mbar pressures and eV *** results presented here provide fundamental insights into boron nitride under the extreme conditions relevant to inertial confinement fusion,hydrogen–boron fusion,and high-energy-density physics.

关键词： boron Hugoniot extreme

面向自动驾驶仿真测试的高覆盖切入场景库生成方法

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国公路学报 2024年第7期37卷 237-249页

作者：李鹏辉董倩茹袁赫男胡文浩孙巍谷远利董春娇北京交通大学交通运输学院北京100044 中国汽车工程研究院股份有限公司智能汽车安全技术全国重点实验室重庆401122 国家市场监督管理总局缺陷产品召回技术中心国家市场监管重点实验室(产品缺陷与安全) 北京100101 公安部交通管理科学研究所道路交通安全公安部重点实验室江苏无锡214151

为解决虚拟仿真测试所需高覆盖场景的生成难题,以自动驾驶车辆事故高发的高速公路切入场景为研究对象,基于搭载多源传感器实车采集的自然驾驶数据,开发基于规则的切入场景自动提取算法;选取核心场景要素建立基于运动学特征的车辆切入轨... 详细信息

为解决虚拟仿真测试所需高覆盖场景的生成难题,以自动驾驶车辆事故高发的高速公路切入场景为研究对象,基于搭载多源传感器实车采集的自然驾驶数据,开发基于规则的切入场景自动提取算法;选取核心场景要素建立基于运动学特征的车辆切入轨迹模型,量化分析模型参数分布特征;基于高斯混合模型构建多维度逻辑场景参数联合概率密度函数,在此基础上提出基于哈密尔顿蒙特卡洛(Hamiltonian Monte Carlo,HMC)采样与Jensen-Shannon(JS)散度覆盖度表征的多维空间场景参数高覆盖生成方法。基于所提取的2422例车辆切入片段研究发现:①基于起始时刻主车速度Ve0、相对速度Vr0、车距Dx0、切入时长T、切入车辆横向加速度ay和纵向加速度ax六参数的横纵向运动学模型可有效表征切入车辆运动轨迹,平均拟合均方根误差为0.7 m;②八分量高斯混合模型对切入场景参数的联合概率密度分布拟合效果最佳;③JS散度随着场景采样数量的增加快速下降而后逐渐收敛至0.01,表明HMC方法可实现切入场景参数的快速采样与高覆盖生成;④本方法实现切入数据集片段信息全覆盖所需场景生成数量为2160个,相比于传统马尔科夫蒙特卡洛(Markov Chain Monte Carlo,MCMC)方法所需场景生成量缩小约73倍,测试效率显著提高,推荐用于高速公路全量切入场景库构建。提出的切入场景轨迹模型与高覆盖生成算法具有可解释性、高覆盖度、生成快捷的特点,将为自动驾驶虚拟仿真测试提供有力支撑。

关键词：交通工程高覆盖场景生成哈密尔顿蒙特卡洛仿真测试场景自动驾驶切入

WPS EXCEL在《化工技术经济》教学中的应用

在线全文

学校读者我要写书评

暂无评论

广州化工 2024年第16期52卷 168-171页

作者：牛海丽徐冬梅李敏王静静山东科技大学化学与生物工程学院山东青岛266590

《化工技术经济》课程具有综合性、实用性、实践性等主要特点,结合课程教学目标及毕业要求指标点,为了提高课堂教学效果,调动学生的学习积极性,针对决策上的数据处理、分析内容,改变教学方法,利用计算机的WPS EXCEL软件工具来解决复杂... 详细信息

《化工技术经济》课程具有综合性、实用性、实践性等主要特点,结合课程教学目标及毕业要求指标点,为了提高课堂教学效果,调动学生的学习积极性,针对决策上的数据处理、分析内容,改变教学方法,利用计算机的WPS EXCEL软件工具来解决复杂的财务数据处理,不仅能提高数据的处理速度和精度,而且也能吸引学生的学习兴趣,提升了学习质量。

关键词：内部收益率 WPS EXCEL 财务函数化工技术经济

桨叶分段线性扭转对降低旋翼振动载荷的作用分析

在线全文

学校读者我要写书评

暂无评论

Transactions of Nanjing University of Aeronautics and Astronautics 2024年第3期41卷 278-288页

作者：张宇杭韩东南京航空航天大学航空学院直升机动力学全国重点实验室南京210016

研究了用桨叶分段线性扭转来降低旋翼振动载荷。使用基于弹性梁的旋翼模型用于预测旋翼振动载荷。采用4片桨叶旋翼作为基准旋翼,桨叶形状与UH-60直升机桨叶相似。桨叶被划分为内、中、外3段,讨论了各段扭转对载荷的影响。低速时桨叶每... 详细信息

研究了用桨叶分段线性扭转来降低旋翼振动载荷。使用基于弹性梁的旋翼模型用于预测旋翼振动载荷。采用4片桨叶旋翼作为基准旋翼,桨叶形状与UH-60直升机桨叶相似。桨叶被划分为内、中、外3段,讨论了各段扭转对载荷的影响。低速时桨叶每一段的扭转都能减少桨毂四阶垂向力。当以80 km/h前飞时,中段-24°/R的扭转可使其降低99.5%。桨叶内段的扭转不利于降低桨毂四阶滚转和俯仰力矩,另外两段的扭转则可以在大多数前飞速度时控制这2个振动力矩。使用参数扫描以尽可能降低旋翼振动载荷。降低四阶垂向力方面,低速时桨叶所有段都需要扭转,而高速时未扭转的桨叶表现更好。降低四阶滚转和俯仰力矩方面,在低速时需要桨叶外段高度扭转,而在中高速时则需要桨叶中段的扭转。

关键词：直升机旋翼振动载荷分段桨叶扭转桨毂垂向力滚转力矩俯仰力矩

Situational continuity-based air combat autonomous maneuvering decision-making

在线全文

学校读者我要写书评

暂无评论

Defence Technology(防务技术) 2023年第11期29卷 66-79页

作者： Jian-dong Zhang Yi-fei Yu Li-hui Zheng Qi-ming Yang Guo-qing shi Yong Wu School of Electronics and Information Northwestern Polytechnical UniversityXi'an710129China Military Representative Office of haizhuang Wuhan Bureau in Luoyang Region 471000China

In order to improve the performance of UAV's autonomous maneuvering decision-making,this paper proposes a decision-making method based on situational *** algorithm in this paper designs a situation evaluation function with strong guidance,then trains the Long Short-Term Memory(LSTM)under the framework of Deep Q Network(DQN)for air combat maneuvering *** the continuity between adjacent situations,the method takes multiple consecutive situations as one input of the neural *** reflect the difference between adjacent situations,the method takes the difference of situation evaluation value as the reward of reinforcement *** different scenarios,the algorithm proposed in this paper is compared with the algorithm based on the Fully Neural Network(FNN)and the algorithm based on statistical principles *** results show that,compared with the FNN algorithm,the algorithm proposed in this paper is more accurate and *** with the algorithm based on the statistical principles,the decision-making of the algorithm proposed in this paper is more efficient and its real-time performance is better.

关键词： UAV Maneuvering decision-making Situational continuity Long short-term memory(LSTM) Deep Q network(DQN) Fully neural network(FNN)