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中药房小包装饮片储存养护常见问题浅析

海峡药学 2024年第3期36卷 13-15页

作者：弓剑升窦丹旎无锡市中医医院药学部江苏无锡214072

目的通过阐述中药饮片水分含量的影响因素,探讨中药材小包装水分含量的定量指标,为提高中药房饮片管控水平提供了新的思路。方法通过引入蜜炙饮片含水量公式、水分自由度、包装材料化学成分迁移等概念,阐述中药饮片水分含量与炮制、贮... 详细信息

目的通过阐述中药饮片水分含量的影响因素,探讨中药材小包装水分含量的定量指标,为提高中药房饮片管控水平提供了新的思路。方法通过引入蜜炙饮片含水量公式、水分自由度、包装材料化学成分迁移等概念,阐述中药饮片水分含量与炮制、贮藏、霉菌、薄膜包装之间的相互作用,系统性的总结了中药饮片水分含量的各项影响因子和质控指标。结果中药饮片水分含量与炮制、贮藏、霉菌、薄膜包装等内外因素之间有很大关联性。结论通过引入中药新鲜度,中药材小包装水分含量定量指标,为更好地控制中药材质量提供了参考。

关键词：水分含量霉菌水分活度聚乙烯薄膜

冷超声乳化模式下乳化手柄的谐振频率跟踪系统设计

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应用声学 2024年第4期43卷 807-816页

作者：苗清豪巩丽文杨军周盛王晓春中国医学科学院生物医学工程研究所天津300000 天津迈达医学科技股份有限公司天津300000

为解决传统白内障乳化手柄的频率跟踪方法中频率易失谐以及热损伤大的问题,该研究提出了一种冷超声乳化模式下乳化手柄的谐振频率跟踪系统。首先设计了合适的阻抗匹配网络使谐振网络的串并联谐振频率相互远离至1 kHz以上,扩大了系统的... 详细信息

为解决传统白内障乳化手柄的频率跟踪方法中频率易失谐以及热损伤大的问题,该研究提出了一种冷超声乳化模式下乳化手柄的谐振频率跟踪系统。首先设计了合适的阻抗匹配网络使谐振网络的串并联谐振频率相互远离至1 kHz以上,扩大了系统的可靠频率跟踪范围,避免了谐振频率误跟踪的问题;接着利用乳化手柄在谐振状态下其两端的电压和电流相位相同的原理,根据谐振网络中电压和电流相位的超前滞后关系来调节驱动信号的频率,以维持手柄谐振。手柄在脉冲冷超声乳化的模式下工作,其产热、散热过程交替进行,以此减少乳化手术对手柄和人眼的热损伤。实际的频率跟踪实验表明,该频率跟踪系统跟踪迅速、准确,乳化手柄工作稳定、振幅大、效率高。手柄在100 ms的周期内交替工作(10 ms)和散热(90 ms),系统的有效跟踪范围大于2 kHz,频率调节的分辨率为10 Hz,跟踪时间为3 ms左右,振幅能达到100µm以上,满足了白内障超声乳化手术中的频率跟踪要求。

关键词：冷超声乳化阻抗匹配谐振网络频率跟踪

液压支架材料表面激光熔覆Ni60高硬耐磨涂层的性能

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材料热处理学报 2024年第3期45卷 166-174页

作者：王家胜舒林森巩江涛张朝铭陕西理工大学机械工程学院陕西汉中723001 陕西省工业自动化重点实验室陕西汉中723001

为实现损伤液压支架立柱的再制造修复,采用激光熔覆技术在液压支架立柱材料27SiMn钢表面制备Ni60合金涂层。通过正交试验法研究激光工艺参数对涂层稀释率的影响规律并确定最优工艺参数。利用超景深显微镜、显微硬度计及摩擦磨损试验机... 详细信息

为实现损伤液压支架立柱的再制造修复,采用激光熔覆技术在液压支架立柱材料27SiMn钢表面制备Ni60合金涂层。通过正交试验法研究激光工艺参数对涂层稀释率的影响规律并确定最优工艺参数。利用超景深显微镜、显微硬度计及摩擦磨损试验机等分析了涂层的显微组织、硬度及耐磨性能。结果表明,影响熔覆层稀释率的因素由大到小依次为:激光功率>扫描速度>送粉速度>离焦量。以稀释率为指标的最佳工艺参数组合为A_(1)B_(3)C_(3)D_(3),即激光功率为1500 W、扫描速度为22 mm/s、离焦量为+1 mm、送粉速度为12 g/min。熔覆层整体晶粒细小均匀,涂层上部主要由等轴晶组成,中部主要由等轴晶和树枝晶组成,下部则主要由沿熔合界面生长的胞状晶及柱状晶组成。熔覆层的平均硬度值为729.5 HV0.5,是基体硬度的2.32倍,最高硬度出现在熔覆层顶部的等轴晶区,为756.9 HV0.5。熔覆层的显微硬度压痕棱边平直、四角光滑无裂纹,具有良好的韧性。熔覆层的摩擦系数明显低于基材,且稳定性好于基材,磨损量仅为基材的58%,熔覆层的磨损机制为磨粒磨损和轻微的黏着磨损。

关键词：液压支架激光熔覆 Ni60 硬度耐磨性能

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青海湖地区紫花针茅型高寒草原群落特征变化

草地学报 2024年第4期32卷 1204-1209页

作者：王婷史倩倩祁得胜陈克龙杜岩功青海师范大学生命科学学院青海西宁810008 青海湖国家级自然保护区管理局青海海北812300 中国科学院西北高原生物研究所青海西宁810001

气候变暖促进青藏高原高寒草原分布面积逐渐增加,但有关紫花针茅(Stipa purpurea)型高寒草原生产力与物种丰富度长期变化特征及其驱动因素尚不明确。本研究连续13年观测青海湖地区高寒草地地上生物量、物种丰富度和盖度等指标,阐明了植... 详细信息

气候变暖促进青藏高原高寒草原分布面积逐渐增加,但有关紫花针茅(Stipa purpurea)型高寒草原生产力与物种丰富度长期变化特征及其驱动因素尚不明确。本研究连续13年观测青海湖地区高寒草地地上生物量、物种丰富度和盖度等指标,阐明了植被群落特征的长期变化规律,采用结构方程模型,解析了紫花针茅型高寒草原生产力和物种丰富度的主要影响因素。结果表明,高寒草原地上生物量和物种丰富度均呈现较强的波动上升趋势,平均鲜重和物种数分别为215.41 g·m^(-2)和15,高物种丰富度促进生产力增加;高寒草原群落总盖度和平均高度呈现显著增加趋势。紫花针茅型高寒草原地上生物量和总盖度分别受到年均气温和生产力的显著影响。未来增温气候情景将会显著增加青海湖地区紫花针茅型高寒草原生物量,但降雨量增加会降低物种丰富度。

关键词：高寒草原地上生物量物种丰富度年均气温

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截面型式及槽宽比对高填明洞土压力影响分析

应用力学学报 2024年第2期41卷 330-339页

作者：何永泽李盛后浩斌马莉贡力余云燕兰州交通大学土木工程学院兰州730070 甘肃省交通科学研究院集团有限公司兰州730030

利用离散元软件pFC2D,考虑到土体的离散性与不均匀性,通过分析洞顶平均竖向土压力、内外土柱相对沉降差以及颗粒间接触力链的变化规律,探讨截面型式(矩形、1/4拱形、1/2拱形)及槽宽比(B/b=1.5∶1,2∶1,3∶1,4∶1)变化对高填黄土明洞土... 详细信息

利用离散元软件pFC2D,考虑到土体的离散性与不均匀性,通过分析洞顶平均竖向土压力、内外土柱相对沉降差以及颗粒间接触力链的变化规律,探讨截面型式(矩形、1/4拱形、1/2拱形)及槽宽比(B/b=1.5∶1,2∶1,3∶1,4∶1)变化对高填黄土明洞土压力的影响,结合顾安全公式,分析高填明洞沉降差与土压力间的函数关系,并修正该函数,使其可以适用与不同的截面型式与槽宽比下的高填明洞。结果表明:(1)B/b确定,明洞采用矩形截面时,接触力链在洞顶分布,平均土压力更大,明洞采用拱形截面时,平均土压力更小,但拱顶存在局部应力集中现象;(2)明洞截面型式一定,随着B/b的增大,洞顶平均竖向土压力与沉降差均随之增大,当B/b较小时,边坡作用增强,外侧土柱沉降降低,对内土柱的作用力变小,从而导致明洞顶竖向土压力更小;(3)内外土柱沉降差与附加土压力呈线性相关,相对于矩形截面,拱形截面下较小的沉降差会产生相同的附加土压力,更有利于结构的稳定。

关键词：高填明洞截面型式槽宽比(B/b) pFC2D 土压力沉降差

Numerical Study of Wetting Transitions on Biomimetic Surfaces Using a Lattice Boltzmann Approach with Large Density Ratio

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Journal of Bionic Engineering 2017年第3期14卷 486-496页

作者： Wei gong Yuying Yan sheng Chen Donald Giddings Fluids & Thermal Engineering Research Group Faculty of Engineering University of Nottingham University Park Nottingham NG7 2RD UK Center for Fluids & Thermal Engineering University of Nottingham Ningbo China

The hydrophobicity of natural surfaces has drawn much attention of scientific communities in recent years. By mimicking natural surfaces, the manufactured biomimetic hydrophobic surfaces have been widely applied to green technologies such as self-cleaning surfaces. Although the theories for wetting and hydrophobicity have been developed, the mechanism of wetting transitions between heterogeneous wetting state and homogeneous wetting state is still not fully clarified. As understanding of wetting transitions is crucial for manufacturing a biomimetic superhydrophobic surface, more fundamental discussions in this area should be carried out. In the present work, the wetting transitions are numerically studied using a phase field lattice Boltzmann approach with large density ratio, which should be helpful in understanding the mechanism of wetting transitions. The dynamic wetting transition processes between Cassie-Baxter state and Wenzel state are presented, and the energy barrier and the gravity effect on transition are discussed. It is found that the two wetting transition processes are irreversible for specific inherent contact angles and have different transition routes, the energy barrier exists on an ideally patterned surface and the gravity can be crucial to overcome the energy barrier and trigger the transition.

关键词： wetting transitions biomimetic surfaces energy barrier gravity effect numerical study lattice Boltzmann method

Dynamical separation of rigid bodies in supersonic flow

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Science China(Technological Sciences) 2015年第12期58卷 2110-2121页

作者： LI Tao SUI JingXia gong sheng WU ChuiJie School of aeronautics and astronautics Dalian university of technology School of energy and power engineering Dalian university of technology

A computational investigation of the unsteady separation behavior of rigid bodies in Mach-4 flow is carried out. Two rigid bodies, a sphere and a cube, initially stationary, centroid axially aligned, are released and thereafter fly freely according to the aerodynamic forces experienced. During the separation process, the smaller cube can experience different types of movement and our principal interest here is the non-dimensional transverse velocity of it. The separation behavior is investigated for interactions between a sphere and a cube with different mass ratio and a constant initial distance between them. The qualitative separation behavior and the final transverse velocity of the small body are found to vary strongly with the mass ratio but less sensitive to the initial distance between the two bodies. At a critical mass ratio for a given distance, the smaller body transit from entrainment within the flow region bounded by the larger body's shock to expulsion and the accumulated transverse velocity of the small body is close to maximum. This phenomenon is the so-called ‘shock-wave surfing' phenomenon noted by Laurence & Deiterding for two spheres at hypersonic Mach numbers. Then we investigate the separation behavior of a sphere interaction with a rotary cube and with a non-rotary cube for a given mass ratio and different distance between them. The rotary is found to increase the likelihood of ‘surfing'. Only at a certain initial distance for a given mass ratio the rotary effect of cube can be neglectable.

关键词： separation behavior flow-structure interactions shock waves

Methodological progress in trace amounts of structural water in nominally anhydrous minerals

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Science China Earth Sciences 2016年第5期59卷 901-909页

作者： sheng YingMing gong Bing LI WanCai XIA Mei CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space Sciences University of Science and Technology of China

In the deep Earth, hydrogen mainly occurs as structural hydroxyl and molecular water in minerals and melts, constituting mobile and immobile aqueous components. Hydrous minerals contain hydrogen which occupies a specific structural position and constitutes an indispensable component of chemical formulae. On the other hand, nominally anhydrous minerals do not contain hydrogen in their chemical formulae, but can host trace amounts of water in structural position and lattice defect. The molecular water may occur in the lattice defect as fluid/melt inclusions in minerals. Even though the water content of nominally anhydrous minerals is very limited generally in the order of ppm(parts per million), they may play a significant role in influencing the physicochemical properties of mineral and rock systems. With the continuous improvement of modern instrumentations, the analytical methodology exhibits trends for higher spatial resolution, lower detection limit and integral multiple methods on the water amount and its isotopic ratio. Among these methods, Fourier transform infrared spectrometry remains the most widely used, while secondary ion mass spectrometry, continuous flow mass spectrometry, elastic recoil detection analysis and Raman spectrometry are promising. This paper provides a brief review on the methodological progress and their applications to the analysis of structural water in nominally anhydrous minerals.

关键词： Nominally anhydrous minerals Water content Structural hydroxyl Molecular water Fourier transform infrared spectrometry

Liquid metal spiral coil enabled soft electromagnetic actuator

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Science China(Technological Sciences) 2018年第4期61卷 516-521页

作者： GUO Rui sheng Lei gong HengYi LIU Jing Department of Biomedical Engineering School of MedicineTsinghua UniversityBeijing 100084China Technical Institute of physics and Chemistry Chinese Academy of SciencesBeijing 100190China

Soft robot is a kind of machine form with flexible deformation capability. Making flexible actuators has recently become a hot research topic in the field. In this study, we demonstrated the facile fabrication of a soft electromagnetic actuator using liquid metal coil of Ga-In alloys, and designed several illustrative mechanical devices, such as jellyfish like robot, soft fishtail and flexible manipulator. Measurements of the liquid metal coil's electrical properties confirmed that the liquid metal coil was mechanically stable under 48% uniaxial strains. Furthermore, the resistance of the liquid metal coil is stable under 60° bending deformation. Tests on the liquid metal coil's driving properties confirmed that the liquid metal coil(55 mm×55 mm×1 mm) could reach the maximum displacement amplitude of 21.5 mm with the current of 0.48 A. It was shown that the electromagnetic interaction between the magnet and the liquid metal coil enables the coil as a highly efficient actuator. The mechanisms lying behind were interpreted and future applications of such system were discussed.

关键词： liquid metal soft machine electromagnetic actuator magnet artificial system