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1.
采用普通水蒸气蒸馏法提取蕤核挥发油,通过气相色谱-质谱(GC-MS)联用技术进行分析鉴定,共鉴定出33种化学组分,占挥发油总量的78.038%.主要含有斯巴醇(10.265%),亚油酸(8.075%),β-石竹烯(7.278%),7-辛烯-4-醇(6.572%),枯茗醛(4.435%),α-非兰烯醇(4.093%)等。  相似文献   

2.
气相色谱-质谱法分析罗勒中挥发油的化学成分   总被引:2,自引:0,他引:2  
利用水蒸气蒸馏法提取维吾尔药材罗勒中的挥发油成分,并用气相色谱-质谱法分析其化学成分,共鉴定出63种化学成分,占挥发性物质含量的87.49%.在罗勒挥发油中主要化学成分为a-萜品油烯(30.97%),香榧烯醇(20.57%),a-萜品油(6.87%),β-月桂烯(4.75%).δ-愈创水烯(3.19%),杜松烯(3.16%)等.  相似文献   

3.
柚子皮挥发油化学成分分析   总被引:1,自引:0,他引:1  
使用水蒸气蒸馏法提取柚子皮中的挥发油,利用气相色谱-质谱联用技术对柚子皮化学成分进行分离鉴定,采用色谱峰面积归一化法确定各成分的相对含量。分析结果表明,共检测出62种组分,鉴定了其中的31种组分,占挥发油组分总量的50.0%。主要成分是β-蒎烯、4,4A,5,6,7,8-六氢-4,4A-二甲基-6-(1-甲基亚乙基)-(4R-顺)-2(3H)-萘酮、氧化芳樟醇、(E,E)-3,7,11,15-四甲基-1,6,10,14-十六碳四烯-3-醇。  相似文献   

4.
木香挥发油化学成分分析   总被引:2,自引:0,他引:2  
使用水蒸气蒸馏法提取木香中的挥发油,利用气相色谱-质谱联用技术对木香化学成分进行分离鉴定,采用色谱峰面积归一化法确定各成分的相对含量。分析结果表明,共分离出53种组分,鉴定了其中的32个组分,占挥发油组分总量的60.38%。主要成分是(9Z,12Z,15Z)-9,12,15-十八烷基三亚乙基四胺-1-醇,反式石竹烯、α-紫罗酮、香叶基丙酮、石竹素、B-瑟林烯、A-姜黄烯。  相似文献   

5.
采用水蒸汽蒸馏法(HD)及顶空固相微萃取法(HS-SPME)提取青蒿花的挥发性成分,GC-MS法分析其化学组成.已鉴定化合物占挥发性成分的95.01%(HD)和89.55%(HS-SPME).其中1.8-桉叶素(21.32%,20.96%),樟脑(24.34%,19.18%),莰烯(3.04%,5.26%),侧柏烯(3...  相似文献   

6.
采用水蒸气蒸馏法从蒙青绢蒿中提取挥发油,气相色谱-质谱法峰面积归一化法计算各成分的百分含量。从挥发油中共鉴定出50种化合物,占挥发油总量的94.11%。主要成分:3,3,6-三甲基-1,5-庚二烯-4-醇(67.83%),2,3,6-三甲基-1,4-庚二烯-6-醇(8.70%),桉树脑(2.37%),银香菊(2.12%),柠檬醇(1.91%),1-甲醇基-2,2-二甲基-3-异丁烯基-环丙烷(1.62%),乙酸-3,7-二甲基-2,6-辛二烯酯(1.14%)等。本实验首次采用GC-MS对蒙青绢蒿中挥发油化学成分进行了分析,可为该植物挥发油的开发利用提供理论依据。  相似文献   

7.
何平  程力  杨占南  高言明  赵超 《光谱实验室》2010,27(5):1783-1785
分析金钱蒲挥发性化学成分。利用固相微萃取/气相色谱/质谱联用技术对金钱蒲挥发性成分进行研究。共鉴定出47个化学成分,占挥发性总成分的95.64%。金钱蒲主要挥发性化学成分是爱草脑(66.9%),桉叶素(6.19%),α-石竹烯(4.01%),γ-萜品烯(2.79%),β-榄香烯(2.58%),β-水芹烯(2.22%)等。  相似文献   

8.
SPME/GC/MS分析小一点红挥发性化学成分   总被引:1,自引:0,他引:1  
利用固相微萃取/气相色谱/质谱(SPME/GC/MS)联用技术对小一点红挥发性成分进行研究。共鉴定出25种化学成分,占挥发性总成分的91.99%。小一点红主要挥发性化学成分是β-月桂烯(51.18%),3,7,11,15-四甲基-2-十六烯-1-醇(21.55%),β-水芹烯(8.42%),n-十六酸(2.48%)等。  相似文献   

9.
利用乙醚抽提东北苍耳子挥发油,GC-MS结合计算机检索对其化学成分进行分析鉴定,用色谱峰面积归一化法计算各组分的相对含量.分离出89个组分,鉴定了其中74个组分,占总挥发油量的85.63%.东北苍耳子挥发油的主要成分为3-甲基丁酸(16.421%)、3-甲基-戊酸(15.882%)、苯乙醛(11.281%)、已酸(5.051%)、糠醛(4.716%)、苯甲醇(2.358%)、苯乙醇(2.282%)等.  相似文献   

10.
新疆温郁金块根挥发油化学成分研究   总被引:1,自引:0,他引:1  
易新萍  马君刚 《光谱实验室》2010,27(5):1757-1759
采用水蒸气蒸馏法提取了新疆产温郁金块根的挥发油,经气相-质谱联用仪分析其成分,得到52种组分,采用峰面积归一化法计算各组分的相对含量,结果确定了其中45种化合物的结构。确定了新疆温郁金块根挥发油中主要含新莪术二酮(13.29%)、莪术二酮(10.05%)、β-榄香烯(2.54%)等抗肿瘤活性成分,为进一步全面研究开发温郁金提供科学依据。  相似文献   

11.
Cyclic competition game models, particularly the “rock–paper–scissors” model, play important roles in exploring the problem of multi-species coexistence in spatially ecological systems. We propose an extended “rock–paper–scissors” game to model cyclic interactions among five species, and find that two of the five can coexistent when biodiversity disappears, which is different from the “rock–paper–scissors” game. As the number of fingers is five, we named the new model the “fingers” game, where the thumb, forefinger, middle finger, ring finger, and little finger cyclically dominate their subsequent species and are dominated by their former species. We investigate the “fingers” model in two ways: direct simulations and nonlinear partial differential equations. An important finding is that the number of species in a cyclic competition game has an influence on the emergence of biodiversity. To be specific, the “rock–paper–scissors” model is in favor of maintaining biodiversity in comparison with the “fingers” model when the variables (population size, reproduction rate, selection rate, and migration rate) are the same. It is also shown that the mobility and reproduction rate can promote or jeopardize biodiversity.  相似文献   

12.
The differences of the pitch and duration of Chinese syllables between Putonghua (PTH) and Taiwan Mandarin (TM) were studied. The speech materials to be used are not only isolated syllables, but also sentences. The results reveal that: For the isolated syllables, T1 and T2 in TM are influenced by Minnan dialect, therefore their pitch are lower than those in PTH. T3 is fall-rise in PTH, while it is fall in TM. Moreover, the syllable duration sequence for different tone is T3〉T2〉T1〉T4 in PTH, while it is T1〉T2〉T3〉T4 in TM. For the syllables in sentences, T2 is mid-rise in PTH, while it is mid-level in TM. And the T3 is longer than T4 but shorter than T1 or T2 in PTH, while it is the shortest in TM. Furthermore the effects of prosodic phrase boundary on duration for different tones are almost the same in PTH, but the lengthening part of T1 or T2 is longer than that of T3 or T4 in TM.  相似文献   

13.
Downstep in pitch contour of Chinese Putonghua is examined using subtly designed sentences by controlling tone combinations. The results show both automatic and nonautomatic downstep phenomena exist in Chinese. In non-automatic downstep, low tones compress downwards the pitch range of the following syllables. and the main influence of downstep is on topline. Low tone not only lower the topline behind it, but also raise the high tones before it, the effects are compatible with each other. In automatic downstep, the topline of pitch contour in intonational phrase is presented as a linear downtrend, but it differs among speakers due to the effect of personal stress practice. In comparison with downstep phenomenon in other tone or non-tone languages, the downstep ratio in Chinese is not constant, and the domain of downstep is not limited within the adjacent tones.  相似文献   

14.
It is shown that SU(2) QCD admits an dual Abelian-Higgs phase, with a Higgs vacuum of a type-Ⅱ superconductor. This is done by using a connection decomposition for the gluon field and the random-direction approximation. Using a bag picture with soft wall, we presented a calculational procedure for the glueball energy based on the recent proof for wall-vortices [Nucl. Phys. B 741(2006)1].  相似文献   

15.
A multi-conjugate adaptive optics (MCAO) can offer a possibility of widening field of view (FOV) characterized by the isoplanatic angle, and the choose of conjugate height becomes a basic problem for MCAO, which influences the size of iosplanatic angle. Considering the application of lidar, the isoplanatic angle's expressions of two deformable mirrors (DMs) MCAO for uplink and downlink are deduced. The effects of conjugate heights for dual-conjugate AO are thoughtfully discussed, and the isoplanatic angles are further analyzed. The results show that the isopanatic angle varies with the conjugate height and reaches the maximum as the conjugate height is at the optimal altitude. Moreover, the optimal conjugate height changes with the propagation distance.  相似文献   

16.
Due to the limit of response speed of the present single-photon detector, the code rate is still too low to come into practical use for the present quantum key distribution (QKD) system.A new idea is put up to design a quick single-photon detector.This quick single-photon detector is composed of a multi-port optic-fiber splitter and many avalanche photo diodes (APDs).Au of the ports with APDs work on the time division and cooperate with a logic discriminating and deciding unit driven by the clock signal.The operation frequency lies on the number N of ports, and can reach N times of the conventional single-photon detector.The single-photon prompt detection can come true for high repetition-rate pulses.The applying of this detector will largely raise the code rate of the QKD, and boost the commercial use.  相似文献   

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19.
Based on the research in Ref. [5][Materials Science and Engineering, 1989; A122: 57 63], an improved model of heat source is set up, the different modes of Lamb wave in an isotropic sample generated by a chopped electron beam at frequency f are obtained with integral transform and normal function expansion method, and the output signal of PZT coupled at the back surface of the sample is found out. The generation mechanism of SEAM (Scanning Electron Acoustic Microscopy) signal is discussed. It shows that the SEAM is a near field imaging technique with high spatial resolution and its best lateral spatial resolution is about 2√2α (α is the radius of the focused electron beam). Some of experimental results of SEAM images are presented in the paper and it shows that the spatial resolution of SEAM is better than 0.5 μm and smaller than the thermal diffusion length of the sample. Therefore the character of near field imaging in SEAM is also proved experimentally.  相似文献   

20.
Transmission spectra of coupled cavity structures (CCSs) in two-dimensional (2D) photonic crystals (PCs) are investigated using a coupled mode theory, and an optical filter based on CCS is proposed. The performance of the filter is investigated using finite-difference time-domain (FDTD) method, and the results show that within a very short coupling distance of about 3λ, where λ is the wavelength of signal in vacuum, the incident signals with different frequencies are separated into different channels with a contrast ratio of 20 dB. The advantages of this kind of filter are small size and easily tunable operation frequencies.  相似文献   

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