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1.
采用微波消解-FAAS测定了皖南休宁县茶园不同深度土壤中的矿质元素Cu、Cd、Mn、Zn、Fe、Pb的含量,分析了不同深度土壤中矿质元素的分布特征,结果表明,皖南土壤中矿质元素Cu、Cd、Mn、Zn、Pb 5元素含量随土壤深度呈递减趋势,土壤表层的矿质元素(Cu、Cd、Mn、Zn、Pb)含量高于深层的,这与施肥有关,土...  相似文献   

2.
ICP-OES测定两种松树中的矿质元素   总被引:3,自引:0,他引:3  
采用HNO3-HF-HClO4湿法消解木材样品,电感耦合等离子体发射光谱法(ICP-OES)测定思茅松、云南松茎干中的Ca、Fe、K、Mg、P、Mn、Zn等矿质元素。结果表明,思茅松、云南松中的矿质元素表现为不同的含量顺序,思茅松中矿质元素含量为Ca〉K〉Zn〉Mg〉P〉Fe〉Mn,而云南松中矿质元素含量为Ca〉Fe〉K〉Mg〉P〉Mn〉Zn。该方法具有良好的准确度及精密度,加标回收率在95.63%—108%范围内,相对标准偏差(RSD)在0.3%—2.4%范围内,结果可靠,操作方便,可用于其他树木样品中相同矿质元素的测定。  相似文献   

3.
ICP-AES测定肉苁蓉及其提取物中矿质元素含量   总被引:2,自引:0,他引:2  
采用ICP-AES法测定两种肉苁蓉及其提取物中11种矿质元素,结果表明:肉苁蓉中Mn,K,Ca,Mg,Na含量(μg·g-1)显著高于管花肉苁蓉,分别为17.70,16 278.03,1 947.25,1 662.76,106.79;肉苁蓉50%甲醇提取物中Fe,Cu,P含量为水提物的1.5倍、2.4倍、1.1倍,Mn,Zn,K,P,Mg,Na含量为100%甲醇提取物的3.8倍、1.2倍、1.6倍、2.3倍、2.2倍、1.1倍;管花肉苁蓉50%甲醇提取物中Cu和P含量为水提物的1.6倍和1.2倍,Mn,Zn,K,P,Mg,Na,Al含量为100%甲醇提取物的2.0倍、1.6倍、1.6倍、1.4倍、1.8倍、1.2倍、1.2倍;肉苁蓉和管花肉苁蓉内矿质元素在50%甲醇中的溶出率分别是60.79%~83.10%和44.58%~83.84%,且Mn, Zn, K, P, Ca, Na, Al的溶出率显著高于水和100%甲醇提取。此研究为高效利用肉苁蓉药材中的矿质元素提供了科学依据。  相似文献   

4.
矿质元素含量是中药材质量评价的重要指标,且与中药材生长发育、功效物质形成及其疗效发挥密切相关。矿质元素含量及比例因产地、采收时期、采收部位等不同存在差异,但种质是影响中药材矿质元素含量及比例最为稳定和重要的因素。电感耦合等离子体原子发射光谱法(ICP-AES法)可快速同时测定多种矿质元素,目前已广泛应用于中药材矿质元素含量测定。肉苁蓉为著名补益类中药,其矿质元素含量及比例越来越受到人们关注。该研究以不同花色肉苁蓉种质为材料,经硝酸和高氯酸消解后,采用ICP-AES法测定了不同花色肉苁蓉种质中的矿质元素K,P,Ca,Mg,Na,Fe,Mn,Zn,Cu和Mo含量,并对结果进行统计分析与比较。结果表明:(1)种质影响肉苁蓉矿质元素含量,不同花色肉苁蓉种质中均具有丰富的矿质元素K,P,Ca,Mg,Na,Fe,Mn,Zn,Cu,Mo,但含量具有明显差异。(2)不同花色肉苁蓉种质的常量矿质元素均以K含量和累积量最高,P含量和累积量最低;白色花种质K含量和累积量最高,为15.91 mg·g-1和727.76 mg·株-1;淡紫色花种质P含量和累积量最低,为0.45 mg·g-1和21.80 mg·株-1。(3)不同花色肉苁蓉种质的微量矿质元素均以Fe的含量和累积量最高,Mo含量和累积量最低;黄色花种质的Fe含量和累积量最高,达到了722.33 μg·g-1和30 251.29 μg·株-1;淡紫色花种质的Mo含量和累积量最低,为0.11 μg·g-1和5.12 μg·株-1。(4)白色花种质的K,Ca,Mg,Mn,Zn含量和累积量较高,而淡紫色花种质的K,Ca,Mg,Na,Mn含量和累积量较低。(5)种质影响肉苁蓉矿质元素比例,不同花色肉苁蓉种质中的矿质元素比例存在差异,其中K∶P和Fe∶Mn差异较大,而Ca∶Mg和Zn∶Cu差异较小。结果表明:肉苁蓉具有丰富的矿质元素,种质影响肉苁蓉中矿质元素含量、累积量及矿质元素比例,且不同花色种质间存在较大差异,应引起关注和重视。矿质元素为中药材质量评价的重要指标且影响中药材生长发育,研究结果可为不同花色肉苁蓉种质质量评价、营养价值评价及科学合理施肥提供依据。  相似文献   

5.
油菜籽中含有丰富的人体及动物必需的矿质元素,但有关不同品种油菜籽矿质元素含量差异的研究较少。选取我国长江流域冬油菜主产区正在种植的33个双低品种和12个传统双高品种,借助ICP-MS对比分析了两类甘蓝型油菜籽的矿质元素含量。检测结果表明,油菜籽中富含P,K,Ca,Mg,S,Fe,Mn等矿质元素,不同品种油菜籽矿质元素含量有一定差别。双低油菜籽中P,K,Ca,Mg和S的平均含量分别为6.26,10.17,6.75,4.82和4.52 mg·g-1,Fe,Mn,Cu,Zn和B含量为96.20,37.10,3.84,41.61和12.16 μg·g-1;双高油菜籽中P,K,Ca,Mg,S和微量元素Fe,Mn,Cu,Zn,B的平均含量分别为5.97,10.14,6.31,4.50,9.06 mg·g-1和77.03,49.86,3.72,40.58,11.79 μg ·g-1。在测定的10种元素中双低品种有八种(P,K,Ca,Mg,Fe,Cu,Zn和B)高于双高品种,其中Ca,Mg和Fe含量的差异达到显著水平。油菜籽在矿质元素含量上的差异可作为推广应用双低品种的必要因素之一。  相似文献   

6.
微波消解ICP-AES测定黄瓜果实膨大生长过程中的矿质元素   总被引:1,自引:0,他引:1  
采用微波消解电感耦合等离子体-原子发射光谱法对黄瓜果实膨大生长过程中的矿质元素B、Ca、Cu、Fe、K、Mg、Mn、Zn含量进行了测定,分析结果的相对标准偏差为0.22%—6.02%。该方法简单、快速、可靠、灵敏度高,且多元素可以同时测定,能满足实际样品分析需要。实验表明,在黄瓜果实膨大生长过程中,矿质元素的含量发生了显著变化,但整体上都呈下降趋势。在整个果实膨大过程中,Ca、K、Mg含量最高,Cu、Mn含量最低。该研究结果为今后深入研究矿质元素与果实膨大生长的相关性提供了理论依据。  相似文献   

7.
ICP-AES测定中国小麦微核心种质库籽粒矿质养分含量   总被引:11,自引:0,他引:11  
矿质营养,尤其是微量元素Fe和Zn对于人体健康的影响已经受到广泛的关注。了解我国小麦籽粒矿质养分状况对于通过育种途径改善作物品质以及人体健康有重大意义。该研究采用微波消解,ICP-AES分析方法对262份我国小麦微核心种质库的籽粒微量元素(Fe, Mn, Zn, Cu)和其他矿质养分(Mg, Ca, K, P)含量进行了分析测定,结果表明我国小麦籽粒中八种矿质营养元素浓度都存在显著的基因型差异;小麦籽粒中Fe, Mn, Zn, Cu四种微量元素浓度间均存在明显的正相关关系,Fe和Mn相关系数为0.395**,Fe和Zn 为0.424**,Fe和Cu为0.574**,Mn和Cu为0.474**。春性和冬性小麦间籽粒八种矿质养分含量基本没有差异。这些研究结果为进行籽粒富含矿质营养小麦品种的选育提供了重要依据。  相似文献   

8.
以HNO3+HClO4消解向日葵根、茎、叶、花盘等器官,采用ICP-AES测定河套灌区盐碱胁迫下向日葵植株对十种矿质元素的吸收和积累。结果表明:(1)Fe,Mn,Zn,Ca,Na在向日葵根部含量最高,K含量在茎中最高,B和Mg在叶中含量最高,花盘中P含量高于其他部位,Cu含量在向日葵各器官间无明显差异;(2)向日葵器官间矿质元素累积量差异表现为花盘中Ca,Mg,P,Cu,B,Zn累积量最高,根Na,Fe,Mn累积量最高,茎K累积量最高;(3)向日葵全株常量矿质元素累积量比值为K∶Ca∶Mg∶P∶Na=16.71∶5.23∶3.86∶1.23∶1.00,微量矿质元素积累量比值为Zn∶Fe∶B∶Mn∶Cu=56.28∶27.75∶1.93∶1.17∶1.00;(4)盐分胁迫对向日葵矿质元素吸收的影响因部位及元素种类各异,根部矿质元素含量对土壤盐分变化最为敏感,茎、叶次之,花盘元素含量变化动态较为复杂。  相似文献   

9.
微波消解ICP-AES测定苋菜的矿质元素   总被引:2,自引:0,他引:2  
孙涌栋  杜晓华 《光谱实验室》2010,27(5):1780-1782
采用微波消解电感耦合等离子体-原子发射光谱法测定了苋菜中的矿质元素Ca、Cd、Cr、Cu、K、Fe、Mg、Mn、Na和Zn的含量,分析结果的相对标准偏差为0.12%—5.72%。该方法简单、快速、可靠、灵敏度高,且多元素可以同时测定,能满足实际样品分析需要。实验表明,苋菜中含有丰富的矿质元素,尤其是Ca、K、Mg含量较高,显示了苋菜较高的营养价值。  相似文献   

10.
各种矿质元素在荆芥各器官间贮藏差异。从矿质元素角度了解荆芥合理的药用部位组成以及收时间。应用ICP-AES技术,测定并分析了在不同采收时间,荆芥的不同器官矿质元素含量、累积量和比例。结果显示, 在不同采收时间,(1)荆芥穗中常量矿质元素K, P和微量矿质元素Cu含量最高,荆芥叶中常量元素Mg, Ca, Na和微量元素Fe, Mn, Zn含量最高。(2)荆芥不同器官所含常量元素中Ca和K含量最高,Na含量最低;所含微量元素中Fe含量最高,Mo含量最低。(3)在荆芥茎中,K∶P最高,而Zn∶Cu则为最低;Ca∶Mg和Fe∶Mn在荆芥穗中最低。(4)随着采收时间的推移,各元素在荆芥不同器官中的含量变化并不显著。荆芥茎中各矿质元素含量均较低; 从矿质元素含量的角度看,在合理的采收时间范围内,荆芥的质量受时间影响不显著。  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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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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