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经后路椎体次全切除三柱重建治疗不稳定性胸、腰椎单发爆裂骨折的临床研究
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作者 卢朝黎 《中国医药导报》 CAS 2012年第31期52-54,共3页
目的探讨经后路椎体次全切除三柱重建治疗不稳定性胸、腰椎单发爆裂骨折的临床疗效。方法选取本院2009年2月~2011年2月收治的不稳定性胸、腰椎单发爆裂骨折患者26例,均采用后路椎体次全切除三柱重建术治疗,比较患者治疗前后的各项临床... 目的探讨经后路椎体次全切除三柱重建治疗不稳定性胸、腰椎单发爆裂骨折的临床疗效。方法选取本院2009年2月~2011年2月收治的不稳定性胸、腰椎单发爆裂骨折患者26例,均采用后路椎体次全切除三柱重建术治疗,比较患者治疗前后的各项临床指标。结果患者均顺利完成手术,手术时间为(192.4±30.7)min,术中出血量为(685.1±219.3)mL,术后24 h的伤口引流量为(327.4±48.1)mL,骨折愈合时间为(17.9±3.2)周。术后患者发生脊柱曲度异常改变1例,感染2例,术后并发症的发生率为11.5%。患者术后的伤椎前缘高度、伤椎后缘高度、椎管容积率均明显大于术前,Cobb角明显小于术前,差异均有统计学意义(P〈0.05)。患者术后的Frankel分级评定情况明显好于术前(P〈0.05)。结论经后路椎体次全切除三柱重建治疗不稳定性胸、腰椎单发爆裂骨折具有显著的临床疗效,可以明显改善患者的临床指标,恢复脊柱生理曲度并重建脊柱稳定性,是一种安全有效的手术方法,值得临床推广使用。 展开更多
关键词 后路椎体次全切除 三柱重建 稳定性胸、腰椎发爆裂骨折
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人造基床单桩稳定性的二维离散元模拟
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作者 赵晖 刘军 《岩土力学》 EI CAS CSCD 北大核心 2008年第12期3407-3411,共5页
人造基床是海洋码头与平台建设中的一项新技术。应用自行开发的离散元程序,模拟了人造基床中的单桩稳定性,所模拟的人造基床由袋装碎石与袋装砂两层组成。在保持袋装砂层高度不变的前提下,分别模拟了不同袋装碎石高度下桩在潮汐作用下... 人造基床是海洋码头与平台建设中的一项新技术。应用自行开发的离散元程序,模拟了人造基床中的单桩稳定性,所模拟的人造基床由袋装碎石与袋装砂两层组成。在保持袋装砂层高度不变的前提下,分别模拟了不同袋装碎石高度下桩在潮汐作用下的稳定性、罕见潮汐作用下桩的失稳过程。程序中用整体阻尼代表海水的阻尼作用。模拟结果表明,离散元法可以很好地体现人造基床与桩接触处的局部大变形特征,同时可通过模拟结果确定最佳人造基床高度。 展开更多
关键词 人造基床 离散元 稳定性 数值模拟
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生物芯片表面氨基密度检测及稳定性研究 被引量:6
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作者 赵剑英 李玉邯 +1 位作者 郭海全 高连勋 《分析化学》 SCIE EI CAS CSCD 北大核心 2006年第9期1235-1238,共4页
用不同氨基硅氧烷试剂在石英或玻璃片基表面上进行氨基化反应,将氨基化片基与芳香醛反应生成亚胺,再将亚胺水解在已知体积的乙酸水溶液中,得到相应的芳香醛溶液,利用UV-vis光谱检测其吸光度。这样,在水解液中检测到的醛的数量等于片基... 用不同氨基硅氧烷试剂在石英或玻璃片基表面上进行氨基化反应,将氨基化片基与芳香醛反应生成亚胺,再将亚胺水解在已知体积的乙酸水溶液中,得到相应的芳香醛溶液,利用UV-vis光谱检测其吸光度。这样,在水解液中检测到的醛的数量等于片基表面生成的亚胺的数量。由已知的水解液体积和片基表面积可以计算出片基表面氨基的相对密度。因9-蒽醛具有较大的摩尔消光系数(262 nm,6.36×107cm2/mol,0.8%CH3COOH aq.),所以,可以明显提高生物芯片表面氨基密度检测的灵敏度。实验还研究了各种氨基化试剂组装成膜的最佳反应条件及其在去离子水、酸性及碱性水溶液中的稳定性,结果表明:氨基化片基在去离子水中有很好的稳定性。 展开更多
关键词 氨基化 微流体 层膜 稳定性 多层膜
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Interfacial Modification of NiO_(x)by Self-assembled Monolayer for Efficient and Stable Inverted Perovskite Solar Cells 被引量:1
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作者 Xin Yu Yandong Wang +5 位作者 Liufei Li Shantao Zhang Shuang Gao Mao Liang Wen-Hua Zhang Shangfeng Yang 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第4期553-562,I0080-I0091,I0095,共23页
NiO_(x)as a hole transport material for inverted perovskite solar cells has received great attention owing to its high transparency,low fabrication temperature,and superior stability.However,the mismatched energy leve... NiO_(x)as a hole transport material for inverted perovskite solar cells has received great attention owing to its high transparency,low fabrication temperature,and superior stability.However,the mismatched energy levels and possible redox reactions at the NiO_(x)/perovskite interface severely limit the performance of NiO_(x) based inverted perovskite solar cells.Herein,we introduce a p-type self-assembled monolayer between NiO_(x)and perovskite layers to modify the interface and block the undesirable redox reaction between perovskite and NiO_(x)The selfassembled monolayer molecules all contain phosphoric acid function groups,which can be anchored onto the NiOr surface and passivate the surface defect.Moreover,the introduction of self-assembled monolayers can regulate the energy level structure of NiO_(x),reduce the interfacial band energy offset,and hence promote the hole transport from perovskite to NiO_(x)layer.Consequently,the device performance is significantly enhanced in terms of both power conversion efficiency and stability. 展开更多
关键词 Perovskite solar cell NiO_(x) Self-assembled monolayer Interfacial engineering Stability
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膝关节本体感觉康复的研究进展 被引量:17
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作者 黄红拾 周谋望 《中国康复医学杂志》 CAS CSCD 2003年第9期567-569,共3页
关键词 本体感觉 康复 稳定性 膝关节运动创伤 前交叉韧带重建
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一类二维神经网络的动力学研究
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作者 徐芳 《计算机应用研究》 CSCD 北大核心 2011年第6期2040-2042,2045,共4页
探讨了一类二维神经网络可能存在的复杂动力学行为。首先利用反证法,获得了这类神经网络的一个不变集,以保证从这个集合出发的所有轨迹最终都在这个集合中。然后利用向量场的旋转数理论,通过构建一个封闭曲线证明了这类网络平衡点的存... 探讨了一类二维神经网络可能存在的复杂动力学行为。首先利用反证法,获得了这类神经网络的一个不变集,以保证从这个集合出发的所有轨迹最终都在这个集合中。然后利用向量场的旋转数理论,通过构建一个封闭曲线证明了这类网络平衡点的存在性。此外,利用反证法证明了该网络的有界性。最后通过数值模拟,验证了分析结果。 展开更多
关键词 神经网络 单稳定性 稳定性 平衡点 不变集
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沥青混合料高温性能试验的对比研究 被引量:6
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作者 谭巍 周刚 《石油沥青》 2009年第4期4-8,共5页
通过对同种沥青混合料进行多种高温性能试验,对不同的试验方法进行了对比研究。试验结果表明:对于象SMA这种粗集料嵌挤作用比较强的混合料,使用无侧限的试验评价其高温抗变形能力会忽略掉一部分集料的嵌挤力,并有可能将其抗高温变形性... 通过对同种沥青混合料进行多种高温性能试验,对不同的试验方法进行了对比研究。试验结果表明:对于象SMA这种粗集料嵌挤作用比较强的混合料,使用无侧限的试验评价其高温抗变形能力会忽略掉一部分集料的嵌挤力,并有可能将其抗高温变形性能归为差的一类。 展开更多
关键词 沥青混合料 高温稳定性马歇尔稳定度车辙试验轴压缩蠕变 贯入
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外墙悬挑式脚手架的设计实例
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作者 诸谧琳 陈敏 《金陵职业大学学报》 2001年第1期12-14,26,共4页
本文结合工程实例 ,介绍碗扣式悬挑钢管脚手架的荷载计算、整体稳定和单肢稳定计算等设计方法。
关键词 外墙悬挑式脚手架 碗扣式脚手架 荷载 整体稳定性 稳定性 设计方法
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笼形水合簇中水分子对与氢键能的关系 被引量:1
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作者 余雨田 胡晓敏 +1 位作者 雷鸣 杨作银 《北京化工大学学报(自然科学版)》 CAS CSCD 北大核心 2018年第6期6-12,共7页
对随机产生的一系列512、51262和435663笼形水合簇,使用DFT/B97D/6-311++g(2d,2p)以及DFT/M052X/6-311++g(2d,2p)方法计算其能量,并讨论了这3种笼形水合簇中不同水分子对的分布与氢键的键能、笼形水合簇稳定性之间的关系。结果表明,对于... 对随机产生的一系列512、51262和435663笼形水合簇,使用DFT/B97D/6-311++g(2d,2p)以及DFT/M052X/6-311++g(2d,2p)方法计算其能量,并讨论了这3种笼形水合簇中不同水分子对的分布与氢键的键能、笼形水合簇稳定性之间的关系。结果表明,对于3种笼形水合簇,若只考虑近邻水分子对中心水分子对的影响,则各笼形结构中只有4种氢键类型,只要确定其中1种氢键类型的个数,其他3种氢键类型的个数也可以被确定; 3种笼形水合簇中氢键的平均能量和单个氢键的平均能量都随n(1221)值的增大而增加;但是在n(1221)值相同时,不同笼形水合簇中单个氢键的平均值几乎相同;当n(1221)值不同时,不同笼形水合簇的氢键网络能量出现重叠,说明笼形水合簇稳定性与4种氢键类型的分布值之间无严格对应关系。 展开更多
关键词 水合簇异构体 水合簇的分布 氢键网络类型 氢键网络能量 稳定性
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Stability analysis of ellipse- like suspen-dome structures with low rise-span ratio 被引量:2
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作者 丁明珉 罗斌 +2 位作者 陈项南 郭正兴 管东芝 《Journal of Southeast University(English Edition)》 EI CAS 2016年第1期51-57,共7页
To investigate the effects of initial geometric imperfection and material nonlinearity on the stability analysis of the suspen-dome, the steel roof of Jiangsu Culture Sports Center Gymnasium was utilized as a numerica... To investigate the effects of initial geometric imperfection and material nonlinearity on the stability analysis of the suspen-dome, the steel roof of Jiangsu Culture Sports Center Gymnasium was utilized as a numerical model, and modal analyses were performed. Then, linear buckling analysis,geometric nonlinear stability analysis, geometric nonlinear stability analysis with initial imperfection, and double nonlinear analysis considering material nonlinearity and geometric nonlinearity were discussed in detail to compare the stability performance of the ellipse-like suspen-dome and the single-layer reticulated shell. The results showthat the cable-strut system increases the integrity of the suspen-dome, and moderates the sensibility of the single-layer reticulated shell to initial geometric imperfection. However, it has little influence on integral rigidity, fundamental vibration frequencies, linear ultimate live loads, and geometric nonlinear ultimate live loads without initial imperfection. When considering the material nonlinearity and initial imperfection, a significant reduction occurs in the ultimate stability capacities of these two structures. In this case, the suspen-dome with a lowrise-span ratio is sensitive to the initial imperfection and material nonlinearity. In addition, the distribution pattern of live loads significantly influences the instability modes of the structure, and the uniform live load with full span is not always the most dangerous case. 展开更多
关键词 SUSPEN-DOME single-layer reticulated shell ellipselike stability analysis initial geometric imperfection geometric nonlinearity material nonlinearity
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基于钢护筒的植桩平台的特点及植桩锚固体系设计 被引量:2
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作者 徐雪锋 《水运工程》 北大核心 2015年第9期161-165,共5页
采用钢护筒支撑形成的"植桩平台"具有适应复杂的工程地质条件、减少大型船机设备的投入使用、加快施工进度、避免打入钢护筒造成钢护筒受力变形的特点。通过控制翻浆孔口的位置和大小、调节锚固混凝土的和易性可以保证钢护筒... 采用钢护筒支撑形成的"植桩平台"具有适应复杂的工程地质条件、减少大型船机设备的投入使用、加快施工进度、避免打入钢护筒造成钢护筒受力变形的特点。通过控制翻浆孔口的位置和大小、调节锚固混凝土的和易性可以保证钢护筒具有足够的翻浆高度,使钢护筒与基岩间形成足够长度的刚性节点,确保钢护筒在汛期内的的单桩稳定性。 展开更多
关键词 植桩平台 翻浆高度 桩端嵌固 稳定性
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Rational construction of thermally stable single atom catalysts:From atomic structure to practical applications 被引量:5
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作者 Hongwei Lv Wenxin Guo +2 位作者 Min Chen Huang Zhou Yuen Wu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第1期71-91,共21页
As a new frontier in catalysis field,single-atom catalysts(SACs)hold unique electronic structure and high atom utilization,which have displayed unprecedented activity and selectivity toward a wide range of catalytic r... As a new frontier in catalysis field,single-atom catalysts(SACs)hold unique electronic structure and high atom utilization,which have displayed unprecedented activity and selectivity toward a wide range of catalytic reactions.However,many reported SACs are susceptible to Ostwald ripening process in high temperature environment or long-term catalytic application,which will cause sintering and deactivation.This is due to the weak interaction between the metal atom and supports.The regeneration and recycling of deactivated catalysts will greatly increase the time and economic cost of industrial production.Therefore,it is necessary to develop SACs with excellent thermal stability to meet the industrial demands.Here,we discuss the fundamental comprehension of the stability of thermally stable SACs obtained from different synthesis methods.The influences of the speciation of metal centers and coordination environments on thermal stability are summarized.The importance of using novel in situ and operando characterizations to reveal dynamic structural evolution under synthesis and reaction conditions and to identify active sites of thermally stable SACs is highlighted.The mechanistic understanding of the unique role of thermally stable SACs in thermocatalytic application is also discussed.At last,a brief perspective on the remaining challenges and future directions of thermally stable SACs is presented. 展开更多
关键词 Thermal stability Single-atom catalyst Sintering and deactivation Synthesis method Thermocatalytic application
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大圆筒结构施工控制要点
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作者 徐建军 马国平 刘春燕 《水运工程》 北大核心 2017年第B05期82-85,共4页
针对大圆筒结构在无掩护条件下施工难的问题,从大圆筒直径大、采用换填工艺、结构要求百年防腐、采用多种方式进行稳定计算的特点以及施工海域风浪大、测量定位精度要求高等特点,首次采用12锤联动的施工工艺,总结了大圆筒结构焊接质量... 针对大圆筒结构在无掩护条件下施工难的问题,从大圆筒直径大、采用换填工艺、结构要求百年防腐、采用多种方式进行稳定计算的特点以及施工海域风浪大、测量定位精度要求高等特点,首次采用12锤联动的施工工艺,总结了大圆筒结构焊接质量高、重防腐工厂化、监控全程化,水下基槽开挖精度高,施工步距合理,定期对筒体进行原型观测等施工要点。 展开更多
关键词 大圆筒 液压振动锤 稳定性 钢结构防腐
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基于APDL的起重机桁架式吊臂优化设计 被引量:1
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作者 刘志坚 《建设机械技术与管理》 2014年第9期87-89,共3页
本文以起重机桁架式吊臂固定截面和最大吊臂长度时的腹管壁厚、外径及主弦管壁厚、外径为设计变量,以吊臂总体重量最小为优化目标,考虑吊臂强度、刚度、整体稳定性以及单肢稳定性等约束条件,在Ansys软件内通过APDL语言建立优化模型。对... 本文以起重机桁架式吊臂固定截面和最大吊臂长度时的腹管壁厚、外径及主弦管壁厚、外径为设计变量,以吊臂总体重量最小为优化目标,考虑吊臂强度、刚度、整体稳定性以及单肢稳定性等约束条件,在Ansys软件内通过APDL语言建立优化模型。对特定吨位的起重机吊臂进行优化分析,得到符合限制条件且重量最轻的吊臂最优设计方案。 展开更多
关键词 APDL 桁架式吊臂 整体稳定性 稳定性
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Overview on permanent magnetic actuator
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作者 撒鹏飞 《Journal of Chongqing University》 CAS 2006年第1期19-23,共5页
Permanent magnetic actuator (PMA), as a new electronic actuator of vacuum circuit breakers, certainly will be used to replace the traditional mechanical actuator. It has such advantages as simple structure, high rel... Permanent magnetic actuator (PMA), as a new electronic actuator of vacuum circuit breakers, certainly will be used to replace the traditional mechanical actuator. It has such advantages as simple structure, high reliability, free maintenance, and so on. This paper summarizes the development, structure, magnetic analysis, character analysis, and control strategy of PMA, and also predicts the future trend of PMA development 展开更多
关键词 PMA mono-stability bi-stability dynamic analysis
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Singular Stabilization and H_∞ Control of Nonlinear Systems with Ordinary Homogeneous Properties
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作者 FANG Jian-yin MU Xiao-wu 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第3期280-288,共9页
In this paper, the nonlinear singular stabilization, H∞ control problem of systems with ordinary homogeneous properties is considered. At first, we discuss the stabilization problems of nonlinear systems with homogen... In this paper, the nonlinear singular stabilization, H∞ control problem of systems with ordinary homogeneous properties is considered. At first, we discuss the stabilization problems of nonlinear systems with homogeneous. Secondly, by vitue of Hamilton-Jacobi-Isaacs equations or inequalities, we solve regular H∞ of nonlinear systems with homogeneous properties. To overcome the H∞ problem of singular nonlinear system, we try to transform inputs of the singular nonlinear system into two parts: regular part input and singular part input. Following the previous results, we solve the singular nonlinear system H∞ control, we give the Lyapunov function and the state feedback controller of the singular nonlinear systems with homogeneous properties. 展开更多
关键词 STABILIZATION H∞ control homogeneous system singular system regular system feedback state control
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Stability of Low Crested and Submerged Breakwaters with Single Layer Armouring 被引量:4
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作者 Markus Muttray Erik ten Oever Bas Reedijk 《Journal of Shipping and Ocean Engineering》 2012年第3期140-152,共13页
The stability of single layer armour units on low crested and submerged breakwaters has been investigated in 2D hydraulic model tests. Armour unit movements including settlements, rocking and displacements have been d... The stability of single layer armour units on low crested and submerged breakwaters has been investigated in 2D hydraulic model tests. Armour unit movements including settlements, rocking and displacements have been determined. The effect of freeboard, packing density and wave steepness on the armour layer stability on crest, front and rear slope has been investigated. Armour units were mostly displaced in the most upper part of the seaward slope and at the seaward side of the crest. Damage on the crest was progressing towards the rear slope. About 40% to 50% larger armour units are required on the seaward slope and crest of low crested structures (as compared to conventional high crested breakwaters). About 35% larger armour units are required on the rear slope. Larger armour units are not required on submerged breakwaters if the water depth on the crest exceeds 40% of design wave height. 展开更多
关键词 Rubble mound breakwater low crested breakwater armour layer stability single layer armour units Xbloc.
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Impact of MTT based tumor chemosensitivity assay in vitro 被引量:1
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作者 Mancang Zhao Wenqing Wei Jing Liu Yan Zhang Juan Jiao Yao Fu Ping An 《The Chinese-German Journal of Clinical Oncology》 CAS 2009年第9期546-548,共3页
Objective: The aim of the study was to evaluate the impact of the chemosensitivity assay in vitro and establish a standard process of measuring the anti-cancer drug sensitivity with MTT assay. Methods: Some influenc... Objective: The aim of the study was to evaluate the impact of the chemosensitivity assay in vitro and establish a standard process of measuring the anti-cancer drug sensitivity with MTT assay. Methods: Some influencing factors of MTT assay in studying the sensitivity of human peripheral blood mononuclear cells (PBMC) to anti-cancer drugs were observed, including red blood cells, platelets, three different kinds of DMSO and different concentrations of MTT. Meanwhile the stability of tumor drug-coated plate was monitored. Results: The red blood cells and platelets may affect the results at a certain range of concentration. Analytical pure DMSO, both imported and domestic reagents showed the same color with MI3-, and the A values of the reaction were dependent on MTT dose. The stability of the freeze-drying drug-coated plates was superior to non freeze-drying ones. Conclusion: To make clear and definite all kinds of influencing factors might contribute to a kind of standard MTT assay for drug sensitivity test in vitro. 展开更多
关键词 TUMOR CHEMOSENSITIVITY influencing factors MTT colormetdc assay
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Stability and changes in astaxanthin ester composition from Haematococcus pluvialis during storage 被引量:8
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作者 苗凤萍 耿亚洪 +2 位作者 卢大炎 左进城 李夜光 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第6期1181-1189,共9页
In this paper,we investigated the effects of temperature,oxygen,antioxidants,and corn germ oil on the stability of astaxanthin from Haematococcus pluvialis under different storage conditions,and changes in the composi... In this paper,we investigated the effects of temperature,oxygen,antioxidants,and corn germ oil on the stability of astaxanthin from Haematococcus pluvialis under different storage conditions,and changes in the composition of astaxanthin esters during storage using high performance liquid chromatography and spectrophotometry.Oxygen and high temperatures(22–25°C) significantly reduced the stability of astaxanthin esters.Corn germ oil and antioxidants(ascorbic acid and vitamin E)failed to protect astaxanthin from oxidation,and actually significantly increased the instability of astaxanthin.A change in the relative composition of astaxanthin esters was observed after 96 weeks of long-term storage.During storage,the relative amounts of free astaxanthin and astaxanthin monoesters declined,while the relative amount of astaxanthin diesters increased.Thus,the ratio of astaxanthin diester to monoester increased,and this ratio could be used to indicate if astaxanthin esters have been properly preserved.If the ratio is greater than 0.2,it suggests that the decrease in astaxanthin content could be higher than 20%.Our results show that storing algal powder from H.pluvialis or other natural astaxanthin products under vacuum and in the dark below 4°C is the most economical and applicable storage method for the large-scale production of astaxanthin from H.pluvialis.This storage method can produce an astaxanthin preservation rate of at least 80%after 96 weeks of storage. 展开更多
关键词 Haematococcus pluvialis astaxanthin ester storage stability storage life high performance liquid chromatography (HPLC)
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东江特大桥浅覆盖层水上钻孔平台设计与施工过程分析
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作者 郭佳嘉 康学云 《交通工程建设》 2011年第4期12-15,共4页
本文以东江特大桥为背景,对采用有限元方法对大桥水上钻孔平台进行承载力及稳定性分析,并对该大桥的浅覆盖层水上临时施工平台单桩稳定性进行深入分析,为该大桥的水上钻孔平台的安全施工提供了指导。实践证明水上施工平台设计合理,... 本文以东江特大桥为背景,对采用有限元方法对大桥水上钻孔平台进行承载力及稳定性分析,并对该大桥的浅覆盖层水上临时施工平台单桩稳定性进行深入分析,为该大桥的水上钻孔平台的安全施工提供了指导。实践证明水上施工平台设计合理,可供浅覆盖层水域施工作业大型临时工程设计参考。 展开更多
关键词 水上钻孔平台 有限元 浅覆盖层 稳定性分析
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