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野生波纹唇鱼Cheilinus undulates营养成分分析与评价 被引量:12
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作者 区又君 李加儿 《热带海洋学报》 CAS CSCD 北大核心 2010年第3期97-102,共6页
该研究测定了野生波纹唇鱼Cheilinus undulates肌肉的营养成分。结果显示,波纹唇鱼肌肉(鲜样)的水分、粗蛋白、粗脂肪和粗灰分的含量分别为80.97%、18.38%、0.10%和0.49%。肌肉中含有18种氨基酸,总量为15.70%(鲜重),必需氨基酸含量占氨... 该研究测定了野生波纹唇鱼Cheilinus undulates肌肉的营养成分。结果显示,波纹唇鱼肌肉(鲜样)的水分、粗蛋白、粗脂肪和粗灰分的含量分别为80.97%、18.38%、0.10%和0.49%。肌肉中含有18种氨基酸,总量为15.70%(鲜重),必需氨基酸含量占氨基酸总量的39.37%,必需氨基酸的组成符合FAO/WHO的标准。氨基酸的支/芳值为2.5654,接近正常人的支/芳值;依据氨基酸评分(AAS)结果,第一限制性氨基酸为苏氨酸(Thr),第二限制性氨基酸为色氨酸(Trp);必需氨基酸指数(EAAI)为68.46;4种鲜味氨基酸(SAA)的总量为31.85%。脂肪酸中二十碳五烯酸(EPA)+二十二碳六烯酸(DHA)的含量为21.86%。含有人体所必需的钠、钾、钙、镁、铁、铜、锌等元素,表明波纹唇鱼具有较高的营养价值。 展开更多
关键词 波纹唇鱼Cheilinus undulates 生化组成 氨基酸 脂肪酸 矿物质和微量元素
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Scapaundulin C,a novel labdane diterpenoid isolated from Chinese liverwort Scapania undulate,inhibits acetylcholinesterase activity 被引量:1
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作者 KANG Ya-Qi ZHOU Jin-Chuan +2 位作者 FAN Pei-Hong WANG Shu-Qi LOU Hong-Xiang 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2015年第12期933-936,共4页
In the present study, scapaundulin C(1), a new labdane diterpenoid, and four related known compounds scapaundulin A(2), 5?, 8?, 9?-trihydroxy-13E-labden-12-one(3), 5?, 8?-dihydroxy-13E-labden-12-one(4), and(13S)-15-hy... In the present study, scapaundulin C(1), a new labdane diterpenoid, and four related known compounds scapaundulin A(2), 5?, 8?, 9?-trihydroxy-13E-labden-12-one(3), 5?, 8?-dihydroxy-13E-labden-12-one(4), and(13S)-15-hydroxylabd-8(17)-en-19-oic acid(5), were isolated from the Chinese liverwort Scapania undulate(L.) Dum., using column chromatography. The structures of these compounds were determined on the basis of 1D- and 2D-NMR analyses. The acetylcholinesterase(Ach E) inhibitory activity was evaluated using a bioautographic TLC assay and the cytotoxic activity was evaluated by the MTT method. All the compounds were reported for the first time to exhibit moderate Ach E inhibitory activity with minimal inhibitory quantities ranging from 250 to 500 ng. All the compounds were tested for their cytotoxicity against five human tumor cell lines, A549, K562, A2780, Hela, and HT29, and compounds 3 and 4 exhibited moderate inhibitory effects on the growth of A2780 cells. 展开更多
关键词 LIVERWORT Scapania undulate LABDANE DITERPENOID AChE INHIBITORY ACTIVITY CYTOTOXIC ACTIVITY
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Formation Mechanisms of Some Features in Siliceous Upper Cretaceous-Lower Tertiary Beds of Jordan-Undulations, Geodes, Boudinages
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作者 Elias Salameh Hani Khoury 《Open Journal of Geology》 CAS 2024年第4期569-577,共9页
Geode, boudinage, and undulation structures are widely distributed in the siliceous beds of the Upper Cretaceous/Tertiary rocks in Jordan. Their formation was attributed to tectonic forces, syngenetic processes, organ... Geode, boudinage, and undulation structures are widely distributed in the siliceous beds of the Upper Cretaceous/Tertiary rocks in Jordan. Their formation was attributed to tectonic forces, syngenetic processes, organic disintegration processes, subaquatic gliding, compaction and settlement, and meteoritic impacts. In this work, the structural features in the siliceous beds of Jordan are attributed to an interplay of load and directed pressures, and mineralogical transformation processes (opal-A to opal-CT to quartz), governed by pH changes. Tectonic directed pressure was acting in an ESE-WSW direction and is common in the silicified limestone of Upper Cretaceous. 展开更多
关键词 UNDULATIONS Geodes Boudinages Opal-A Porcelanite Chert Transformations pH Changes Stress Fields JORDAN
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Performance of the merged APPLE-Knot undulator for soft x-ray beamline in medium energy ring
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作者 成锐 张发远 +1 位作者 查鹤鸣 乔山 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期240-246,共7页
APPLE-Knot undulator can effectively solve the on-axis heat load problem and is proven to perform well in VUV beamline and soft x-ray beamline in high energy storage ring. However, for soft x-ray beamline in a medium ... APPLE-Knot undulator can effectively solve the on-axis heat load problem and is proven to perform well in VUV beamline and soft x-ray beamline in high energy storage ring. However, for soft x-ray beamline in a medium energy ring,whether the APPLE-Knot undulator excels the APPLE undulator is still a question. Here, a merged APPLE-Knot undulator is studied to generate soft x-ray in a medium energy ring. Its advantages and problems are discussed. Though the on-axis heat load of the APPLE-Knot undulator is lower in linear polarization modes compared to the APPLE undulator, its flux is lower. The APPLE-Knot undulator shows no advantage when only fundamental harmonic is needed. However, in circular polarization mode, the APPLE-Knot undulator shows the ability to cover a broader energy range which can remedy the notable shortcoming of the APPLE undulator. 展开更多
关键词 synchrotron radiation APPLE-Knot undulator soft x-ray
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波纹唇鱼染色体核型分析 被引量:12
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作者 霍蕊 张本 +3 位作者 陈国华 尹绍武 王世锋 齐兴柱 《海洋科学》 CAS CSCD 北大核心 2009年第4期94-97,共4页
为了解波纹唇鱼(Cheilinus undulates)的细胞生物学特征,采用植物血凝集素PHA、秋水仙素腹腔注射和空气干燥制片法以头肾组织为材料,对波纹唇鱼的染色体核型进行了研究。结果表明,波纹唇鱼具有染色体48条,核型公式为2n=48=6m+42t,NF=54... 为了解波纹唇鱼(Cheilinus undulates)的细胞生物学特征,采用植物血凝集素PHA、秋水仙素腹腔注射和空气干燥制片法以头肾组织为材料,对波纹唇鱼的染色体核型进行了研究。结果表明,波纹唇鱼具有染色体48条,核型公式为2n=48=6m+42t,NF=54,未发现随体、次溢痕及性染色体,其核型符合典型的高位类群鱼类核型特征。 展开更多
关键词 波纹唇鱼(Cheilinus undulates) 染色体 核型
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波纹巴非蛤小分子肽在水剂化妆品中的稳定性 被引量:1
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作者 陈得科 陈忻 +4 位作者 陈华 潘剑宇 陈晓刚 刘少余 孙恢礼 《湖北农业科学》 2015年第13期3208-3212,共5页
试验考察了含量、空气暴露时长、光照、pH、化妆品常用防腐剂等因素对波纹巴非蛤(Paphi0 Undu-Zctte)小分子肽抗氧化活性的影响,并研究了其在化妆品体系中的稳定性。结果表明.波纹巴非蛤小分子肽在含量为0.2%~1.0%(m/V)时... 试验考察了含量、空气暴露时长、光照、pH、化妆品常用防腐剂等因素对波纹巴非蛤(Paphi0 Undu-Zctte)小分子肽抗氧化活性的影响,并研究了其在化妆品体系中的稳定性。结果表明.波纹巴非蛤小分子肽在含量为0.2%~1.0%(m/V)时对自由基的清除能力随含量增大而增强,当含量达到1.0%时,羟自由基清除率为66%,超氧阴离子自由基清除率为70%,且24h空气暴露对自由基清除能力无影响:波纹巴非蛤小分子肽的光和pH稳定性良好;常用化妆品防腐剂对其稳定性基本无影响,但避免加入量过大。波纹巴非蛤小分子肽作为抗氧化活性物质适于与大部分水剂化妆品原料进行配伍. 展开更多
关键词 波纹巴非蛤(Paphia undulate)小分子肽 化妆品 稳定性 自由基 抗氧化
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中等长高比腔体内的混合流体Undulation行进波 被引量:5
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作者 齐昕 宁利中 +2 位作者 刘嘉夫 张淑芸 周倩 《西安理工大学学报》 CAS 北大核心 2010年第3期271-276,共6页
通过二维流体力学基本方程组模拟了具有较强Soret效应(分离比ψ=-0.47)的混合流体在中等长高比(Γ=12)腔体内的Rayleigh-Benard对流运动。研究了不同瑞利数情况下腔体内出现的各种行进波状态,详细地探讨了Undulation行进波(UTW)的特性... 通过二维流体力学基本方程组模拟了具有较强Soret效应(分离比ψ=-0.47)的混合流体在中等长高比(Γ=12)腔体内的Rayleigh-Benard对流运动。研究了不同瑞利数情况下腔体内出现的各种行进波状态,详细地探讨了Undulation行进波(UTW)的特性、时空结构及稳定性。 展开更多
关键词 RAYLEIGH-BENARD对流 行进波 Undulation行进波 稳定性
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具有强SORET效应的混合流体Undulation行进波对流斑图 被引量:3
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作者 宁利中 齐昕 +1 位作者 余荔 周洋 《力学季刊》 CSCD 北大核心 2008年第4期521-529,共9页
本文通过流体力学基本方程组的数值模拟,探讨了具有强Soret效应(分离比ψ=-0.6)的混合流体Un-dulation行进波对流斑图的动力学特性。在相对瑞利数r<6.436时,首次发现一种没有源缺陷的左右相对传播的CPW(Counter propagating waves)... 本文通过流体力学基本方程组的数值模拟,探讨了具有强Soret效应(分离比ψ=-0.6)的混合流体Un-dulation行进波对流斑图的动力学特性。在相对瑞利数r<6.436时,首次发现一种没有源缺陷的左右相对传播的CPW(Counter propagating waves)状态向行进波状态的过渡形式。在r=6.436—10.8的范围内,发现了两种不同结构的Undulation行进波对流斑图。当6.436<r<10时,出现了腔体内的平均波数在时间上变化且局部波数或当地波数在空间和时间上连续变化的Undulation行进波对流斑图。当r=10—10.8时,出现了腔体内的平均波数在时间上保持为常数而局部波数或当地波数在空间和时间上连续变化的Undulation行进波斑图。在两种状态下,Undulation行进波的摆动周期随瑞利数r增大而减小,它的对流振幅和Nusselt数随瑞利数r增大而增加。在Undulation行进波斑图形成以前,存在以中心为对称的Undulation行进波斑图,它的存活时间依赖于r。当r增加到11.0时,Undulation行进波过渡到定常对流状态。 展开更多
关键词 混合流体 Undulation行进波 对流 斑图
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起伏面磁场及其梯度张量快速三维正演方法(英文) 被引量:1
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作者 李昆 陈龙伟 +4 位作者 陈轻蕊 戴世坤 张钱江 赵东东 凌嘉宣 《Applied Geophysics》 SCIE CSCD 2018年第3期500-512,共13页
随着磁梯度张量测量技术迅速发展,为实现精细反演地下磁化率分布提供了数据保障。基于航空和陆地磁测数据的三维磁化率反演需要计算起伏面上的磁场,因此研究起伏面磁场及其梯度张量快速三维正演方法具有重要实际应用价值。针对任意磁化... 随着磁梯度张量测量技术迅速发展,为实现精细反演地下磁化率分布提供了数据保障。基于航空和陆地磁测数据的三维磁化率反演需要计算起伏面上的磁场,因此研究起伏面磁场及其梯度张量快速三维正演方法具有重要实际应用价值。针对任意磁化率分布、起伏面磁场及其梯度张量三维正演问题,本文提出了一种快速波数域三维正演方法,其关键环节包括:(1)结合棱柱体组合模型波数域表达式和Gauss-FFT算法,提出一种任意磁化分布情况下平面磁场及其梯度张量快速三维正演算法;(2)利用平面三维正演算法,计算多个高度平面磁场及其梯度张量,结合三次样条插值方法,实现起伏面磁场及其梯度张量三维正演。在此过程中,提出一种多个高度面情况下波数域加权系数快速计算方法,进一步提高了起伏面情况下三维正演的计算效率。通过设计不同模型算例,验证了新方法的计算精度和效率。 展开更多
关键词 undulated surface magnetic fi eld gradient TENSOR 3D FORWARD modeling Gauss– FFT algorithm WAVENUMBER domain
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Distribution and migration of houbara bustard (Chlamydotis undulata) in China
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作者 Olivier COMBREAU 《Journal of Arid Land》 SCIE 2009年第1期74-79,共6页
The distribution and migration of houbara bustard in China was studied by range investigation and tracking through PTT satellite transmitter from 1997 to 2004. The houbara bustard occurs in the Junggar Basin, north pa... The distribution and migration of houbara bustard in China was studied by range investigation and tracking through PTT satellite transmitter from 1997 to 2004. The houbara bustard occurs in the Junggar Basin, north part of Tacheng Basin and valley of Ulungur river in northern Xinjiang, southern part of Turpan Basin and Barkol in eastern Xinjiang. In Inner Mongolia, the houbara bustard occurs in Urathouqi, Alxahouqi and Ejinaqi. In Gansu province, the houbara bustard occurs in Wuwei, Minqin and Shandan. The whole range is not contiguous area. Houbara bastard started migration from Junggar Basin in northern Xinjiang, Turpan Basin and Barkol in eastern Xinjiang, Wuwei in western Gansu Province and Bayan Nur in western Inner Mongolia in the middle of September. Flying to the west and northwest, via Junggar Basin and area between Bole and Habahe in northern Xinjiang, entered Kazakhstan, they turned toward southwest, passed Uzbekistan and Turkmenistan, arrived in Arabia Bay of southern Iran or flied over Afghanistan, arrived in southern Pakistan for wintering. The whole migration usually took 35 +/- 13 days covering a distance of 4 800-7 000 km. In the next year, houbara went back to the breeding grounds in China through the same routes at the beginning of March. However, it took the birds 64 +/- 17 days to finish the spring migration. They arrived in breeding site between middle of April and late May. The sub-adults arrived later and did not breed. 展开更多
关键词 houbara bustard Chlamdotis undulate DISTRIBUTION MIGRATION China
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Computational Study on a Squid-Like Underwater Robot with Two Undulating Side Fins 被引量:15
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作者 Md. Mahbubar Rahman Yasuyuki Toda Hiroshi Miki 《Journal of Bionic Engineering》 SCIE EI CSCD 2011年第1期25-32,共8页
The undulating fin propulsion system is an instance of the bio-inspired propulsion systems. In the current study, the swimming motion of a squid-like robot with two undulating side fins, mimicking those of a Stingray ... The undulating fin propulsion system is an instance of the bio-inspired propulsion systems. In the current study, the swimming motion of a squid-like robot with two undulating side fins, mimicking those of a Stingray or a Cuttlefish, was investigated through flow computation around the body. We used the finite analytic method for space discretization and Euler implicit scheme for time discretization along with the PISO algorithm for velocity pressure coupling. A body-fitted moving grid was generated using the Poisson equation at each time step. Based on the computed results, we discussed the features of the flow field and hydrodynamic forces acting on the body and fin. A simple relationship among the fin's principal dimensions was established. Numerical computation was done for various aspect ratios, fin angles and frequencies in order to validate the proposed relationship among principal dimensions. Subsequently, the relationship was examined base on the distribution of pressure difference between upper and lower surfaces and the distribution of the thrust force. In efficiency calculations, the undulating fins showed promising results. Finally, for the fin, the open characteristics from computed data showed satisfactory conformity with the experimental results. 展开更多
关键词 biomimetics squid robot undulating fin propulsion efficiency HYDRODYNAMICS CFD
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Computational Research on Modular Undulating Fin for Biorobotic Underwater Propulsor 被引量:17
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作者 Yong-hua Zhang Lai-bing Jia +2 位作者 Shi-wu Zhang Jie Yang K. H. Low 《Journal of Bionic Engineering》 SCIE EI CSCD 2007年第1期25-32,共8页
Biomimetic design employs the principles of nature to solve engineering problems. Such designs which are hoped to be quick, efficient, robust, and versatile, have taken advantage of optimization via natural selection.... Biomimetic design employs the principles of nature to solve engineering problems. Such designs which are hoped to be quick, efficient, robust, and versatile, have taken advantage of optimization via natural selection. In the present research, an environment-friendly propulsion system mimicking undulating fins of stingray was built. A non-conventional method was considered to model the flexibility of the fins of stingray. A two-degree-of-freedom mechanism comprised of several linkages was designed and constructed to mimic the actual flexible fin, The driving linkages were used to form a mechanical fin consisting of several fin segments, which are able tO produce undulations, similar to those produced by the actual fins. Owing to the modularity of the design of the mechanical fin, various undulating patterns can be realized. Some qualitative observations, obtained by experiments, predicted that the thrusts produced by the mechanical fin are different among various undulating patterns. To fully understand this experimental phenomenon is very important for better performance and energy saving for our biorobotic underwater propulsion system. Here, four basic undulating patterns of the mechanical fin were performed using two-dimensional unsteady computational fluid dynamics (CFD) method. An unstructured, grid-based, unsteady Navier-Stokes solver with automatic adaptive re-meshing was used to compute the unsteady flow around the fin through twenty complete cycles. The pressure distribution on fin surface was computed and integrated to provide fin forces which were decomposed into rift and thrust. The pressure force and friction force were also computed throughout the swimming cycle. Finally, vortex contour maps of these four basic fin undulating patterns were displayed and compared. 展开更多
关键词 BIOMIMETIC modular undulating fin biorobotic AUV CFD propulsion efficiency
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Parametric Research of Experiments on a Carangiform Robotic Fish 被引量:13
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作者 Qin Yan Zhen Han Shi-wu Zhang Jie Yang 《Journal of Bionic Engineering》 SCIE EI CSCD 2008年第2期95-101,共7页
In this paper, a carangiform robotic fish with 4-DoF (degree of freedom) tail has been developed. The robotic fish has capability of swimming under two modes that are radio control and autonomous swimming. Experimen... In this paper, a carangiform robotic fish with 4-DoF (degree of freedom) tail has been developed. The robotic fish has capability of swimming under two modes that are radio control and autonomous swimming. Experiments were conducted to investigate the influences of characteristic parameters including the frequency, the amplitude, the wave length, the phase difference and the coefficient on forward velocity. The experimental results shown that the swimming performance of the robotic fish is affected mostly by the characteristic parameters observed. 展开更多
关键词 BIOMIMETIC robotic fish experimental parameter matrix undulation equation body length velocity
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Research on Complexity of Surface Undulating Shapes of Rock Joints 被引量:4
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作者 Du Shigui Department of Civil Engineering, Zhejiang University of Technology, Hangzhou 310014 《Journal of Earth Science》 SCIE CAS CSCD 1998年第1期88-91,共4页
The surface undulating shapes of rock joints have been described qualitatively or experimental quantitatively for a long time. The non determined describing method can not fit quantitative evaluation of mechani... The surface undulating shapes of rock joints have been described qualitatively or experimental quantitatively for a long time. The non determined describing method can not fit quantitative evaluation of mechanical parameters of rock joints in engineering. In this paper, relative amplitude ( R A) is chosen as a quantitative describing index of surface measurement of 1 023 surface undulating curves which conducted by profile curve device(PCD). We discuss the nonuniformity,anisotropy and unhomogeneity of surface undulating shapes of joints. A new method that analyzes the complexity of surface undulating shapes of rock joints directional statistically in various rock joints is also put forward. 展开更多
关键词 surface undulating shapes of rock joints relative amplitude ( R A) profile curve device (PCD) NONUNIFORMITY ANISOTROPY unhomogeneity.
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Understanding the Rayleigh instability in humping phenomenon during laser powder bed fusion process 被引量:2
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作者 Wenxuan Zhang Wenyuan Hou +1 位作者 Luc Deike Craig Arnold 《International Journal of Extreme Manufacturing》 SCIE EI 2022年第1期85-92,共8页
The periodic undulation of a molten track’s height profile in laser-based powder bed fusion of metals(PBF-LB/M)is a commonly observed phenomena that can cause defects and building failure during the manufacturing pro... The periodic undulation of a molten track’s height profile in laser-based powder bed fusion of metals(PBF-LB/M)is a commonly observed phenomena that can cause defects and building failure during the manufacturing process.However a quantitative analysis of such instabilities has not been fully established and so here we used Rayleigh–Plateau theory to determine the stability of a single molten track in PBF-LB/M and tested it with various processing conditions by changing laser power and beam shape.The analysis discovered that normalized enthalpy,which relates to energy input density,determines whether a molten track is initially unstable and if so,the growth rate for the instability.Additionally,whether the growth rate ultimately yields significant undulation depends on the melt duration,estimated by dwell time in our experiment. 展开更多
关键词 additive manufacturing powder bed fusion dual lasers UNDULATION humping
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Thermokinetic Behaviour Degenerated from Limit Cycle Oscillation of Isothermal B-Z Reaction System due to Temperature Controlling of Heat Compensation Type 被引量:2
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作者 WenHuaZHANG JiuLiLUO 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第9期1075-1078,共4页
The thermokinetic behavior of the B-Z reaction system was influenced by both the chemical reaction-heat conduction coupling and the temperature undulation due to temperature controlling of heat compensation type. Qua... The thermokinetic behavior of the B-Z reaction system was influenced by both the chemical reaction-heat conduction coupling and the temperature undulation due to temperature controlling of heat compensation type. Quantitative research indicated that this kind of temperature fluctuation will lead to limit cycle degeneration and the periodic or quasi-periodic response behavior of the focus near a supercritical Hopf bifurcation . 展开更多
关键词 Temperature undulation thermokinetic behavior B-Z reaction system.
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EVOLUTIONARY CHARACTERISTICS OF LAKES AND PALAEOCLIMATIC UNDULATION IN THE Q AID AM BASIN,CHINA 被引量:1
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作者 黄麒 Teh-Lung Ku Fred M.Phillips 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1993年第1期34-45,共12页
The Qaidam Basin is. a tectonically controlled depression at 2700 m altitude on the northern margin of the Tibet Plateau. A succession of Neogene clastic sediments indicates lake depocentre migration from NW to SE. To... The Qaidam Basin is. a tectonically controlled depression at 2700 m altitude on the northern margin of the Tibet Plateau. A succession of Neogene clastic sediments indicates lake depocentre migration from NW to SE. Towards late Pliocene, evaporative conditions developed with formation of gypsum, halite, celestite, mirabilite and bloedite. Continued deformation through Pleistocene developed a series of NW- SE trending domes and troughs. This setting continued to exert a controlling influence on basin and brine evolution and the progressive development of sulfate to chloride brines as, dry conditions intensified in late Pleistocene, at the end of which, extensive flat floors were formed in Dalangtan, Qarhan and other playas.The, model, which was set up based on the synthetic analyses, divides the fluctuating palaeoclimate since 750ka,B. P. into 11 warm and humid stages and 10 dry and cold stages. The water of the lakes evaporated during the dry-cold periods and were freshened during the warm-humid 展开更多
关键词 evolution of salt LAKES organic carbon STRATIGRAPHY undulating model of PALEOCLIMATE
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Generation of two-color polarization-adjustable radiation pulses for storage ring light source 被引量:1
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作者 Wei-Hang Liu Yi Wu +2 位作者 Yi Jiao Zheng-He Bai Sheng Wang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第4期123-131,共9页
To date, two-color pulses are widely used in pump–probe experiments. For a ring-based light source, the power of the spontaneous radiation fluctuates randomly in the longitudinal direction. It is difficult to produce... To date, two-color pulses are widely used in pump–probe experiments. For a ring-based light source, the power of the spontaneous radiation fluctuates randomly in the longitudinal direction. It is difficult to produce twocolor double pulses by optical methods. In this paper, we introduce a method based on the echo-enabled harmonic generation scheme that generates two-color pulses in a storage ring light source. By adopting crossed undulators and a phase shifter, the polarization of the two-color pulses can be easily switched. A numerical simulation based on a diffraction-limited storage ring, the Hefei Advanced Light Source, suggests that the time delay and spectral separation of the two pulses can be adjusted linearly by changing the pulse duration and chirp parameters of the seed laser. A circular polarization degree above 80% could be achieved. 展开更多
关键词 Two-color PULSES Echo-enabled harmonic GENERATION Diffraction-limited storage ring CROSSED UNDULATORS Circular polarization
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Brucellosis: Pathophysiology and new promising treatments with medicinal plants and natural antioxidants 被引量:1
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作者 Mohsen Alizadeh Ali Safarzadeh +5 位作者 Mahmoud Bahmani Fatemeh BeyranvAND Mehdi Mohammadi Kimia Azarbaijani Mahmoud Rafieian-Kopaei Saber Abbaszadeh 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2018年第11期597-608,共12页
Brucellosis is an old, infectious and common zoonosis whose causative agents are Gramnegative bacteria from the Brucella genus. Brucellosis is transmitted through direct contactwith infected animals or using unpasteur... Brucellosis is an old, infectious and common zoonosis whose causative agents are Gramnegative bacteria from the Brucella genus. Brucellosis is transmitted through direct contactwith infected animals or using unpasteurized dairy products of goats, pigs, camels, sheep,buffalo and cows. Brucellosis is still the most common zoonosis in the world, with mostof cases occurring in developing countries. Today, an approach to traditional medicine andmedicinal plants, especially with regards to the repeated recommendations of the World HealthOrganization, is a necessity. One-third of chemical drugs are produced by using plants andthere is a high potential to produce more drugs from plants. Medicinal plants are helpful inthe management of various conditions, especially bacterial diseases. Although there is notenough scientific evidence regarding the clinical effectiveness of herbal drugs for the treatmentof brucellosis, there is strong evidence on the antimicrobial effects of herbal drugs to preventinfection. Therefore, this article seeks to describe the antibacterial effects of some plantderived essential oils or extracts, so that they can serve as promising choices to develop newanti-Brucella medications, as suitable alternatives to conventional antibiotics for brucellosis, asmuch as possible, taking into account the benefits of these herbal drugs. 展开更多
关键词 BRUCELLOSIS Undulant FEVER Malta FEVER HERBAL drugs PHYTOTHERAPY Antioxidant
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Crystalline undulator radiation and sub-harmonic bifurcation of system 被引量:1
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作者 罗晓华 何为 +2 位作者 吴木营 邵明珠 罗诗裕 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第6期401-404,共4页
Looking for new light sources, especially short wavelength laser light sources has attracted widespread attention. This paper analytically describes the radiation of a crystalline undulator field by the sine-squared p... Looking for new light sources, especially short wavelength laser light sources has attracted widespread attention. This paper analytically describes the radiation of a crystalline undulator field by the sine-squared potential. In the classical mechanics and the dipole approximation, the motion equation of a particle is reduced to a generalized pendulum equation with a damping term and a forcing term. The bifurcation behavior of periodic orbits is analyzed by using the Melnikov method and the numerical method, and the stability of the system is discussed. The results show that, in principle, the stability of the system relates to its parameters, and only by adjusting these parameters appropriately can the occurrence of bifurcation be avoided or suppressed. 展开更多
关键词 crystalline undulator radiation short wavelength laser Melnikov method BIFURCATION STABILITY
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