LED组合光谱对水培生菜矿物质吸收的影响

在植物工厂全密闭环境中水培种植大速生生菜,以光谱比例可调节的LED灯板为植物生长光源,应用电感耦合等离子体原子发射光谱技术(ICP-AES),研究了红蓝LED组合光谱下生菜对K,P,Ca,Mg,Na,Fe,Mn,Zn,Cu,B,Mo等11种营养元素的吸收特性。结果表明：(1)与叶绿素生理吸收波峰(峰值450和660 nm)对应的单一或组合光谱均可增强水培生菜根对Na, Fe, Mn, Cu, Mo元素的吸收能力,且单一红光光谱的促进作用最为显著,四种元素含量分别为荧光灯全光谱下的7.8, 4.2, 5.3, 11.0倍;(2)根对K和B元素的吸收量在荧光灯全光谱下达到最大分别为10.309 mg·g-1和32.6 μg·g-1,而在红、蓝单一或组合光谱下吸收能力降低;(3)单一蓝色光谱下根对Ca和Mg元素的吸收受到抑制,分别比荧光灯对照降低35%,33%;(4)生菜在30%蓝光+70%红光的光谱条件下生物量最高,而在20%蓝光+80%红光条件下对Ca, Mg, Na, Fe, Mn, Zn, B七种元素的累积量达到最大值。试验结果为水培生菜光源光谱选择及营养液配方调节提供了理论依据。     

ICP-AES分析河套灌区盐碱地向日葵矿质元素吸收与积累

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。     

不同光谱成分条件下叶用莴苣矿质元素吸收分析

以叶用莴苣为试验材料,应用ICP-AES等技术,研究了不同光谱成分及其组合条件下生菜对矿质元素的吸收特性。结果显示:(1)生菜常量、微量矿质元素含量比约为Ca:Mg:K:Na:P=5.5:2.5:2.3:1.5:1.0,Fe:Mn:Zn:Cu:B=25.9:5.9:2.8:1.1:1.0,且LED及荧光灯处理下的生菜各元素含量均高于自然光,差异显著;(2)生菜在红蓝组合LED光R/B=1:2.75处理下对K,P,Ca,Mg,B元素的吸收量及累积量均达最大,LED及荧光灯红光均可显著促进生菜对Fe和Cu元素的吸收;(3)矿质元素含量较高及干物质积累量较高的处理均为LED灯R/B=1:2.75和B/W=1:1。     

采前LED红蓝光连续光照对不同光质与氮形态水培生菜生长及营养元素吸收的影响

红光和蓝光是植物进行光合作用和光形态建成的主要有效光谱,且红蓝发光二极管(LED)成为植物工厂的主流光源。为实现LED连续光照在植物工厂中的应用,探明植物对红蓝光谱连续光照的响应特征及其与栽培氮形态和LED红蓝光质的关系十分必要。在环境可控的植物工厂内,采用水培方法和ICP-AES测试技术,研究了采收前LED红蓝光连续光照(CL)对不同光质与氮形态水培生菜生长及营养元素吸收的影响。在光照强度150μmol·m~(-2)·s~(-1)下,试验设置了3种红(R)蓝(B)光质:2R∶1B(Q_(2∶1)), 3R∶1B(Q_(3∶1))和4R∶1B(Q_(4∶1)),以及2种氮形态:80%硝态氮(N_(80%))和100%硝态氮(N_(100%))。结果表明, CL前, LED光质与营养液氮形态互作处理对水培生菜的地上干重具有显著影响,对地上鲜重及根鲜干重无显著影响,对N, C, P, K, Ca, Mg, Fe, Mn, Cu, Zn的含量及积累量均无显著影响。CL后,光质与营养液氮形态互作处理对水培生菜的根鲜重与根干重有显著影响,对地上鲜干重的影响无显著差异,只对N, P的含量, N, P, Fe, Zn的积累量有显著影响。CL对水培生菜的生物量,矿质元素含量及积累量有显著影响,与CL前相比,地上鲜重,根鲜重,地上干重及根干重均显著增加;各营养元素含量均有不同程度的降低趋势,其中CL显著降低了N, P, Fe, Zn的含量,而对于C, K, Ca, Mg, Mn, Cu的含量无显著影响。CL均显著提高了N, C, P, K, Ca, Mg, Fe, Mn, Cu, Zn的积累量。综上所述, CL前, LED光质与氮形态对生菜地上干重具有显著影响,对各营养元素的含量及积累量均无显著影响。CL后, LED光质与氮形态对根鲜干重具有显著影响,对N, P的含量及N, P, Fe, Zn的积累量具有显著影响, N_(80%)Q_(4∶1)处理积累的量最高。与CL处理前相比,水培生菜的地上鲜重,根鲜重,地上干重及根干重均显著增加; CL显著降低了N, P, Fe, Zn的含量,显著提高了N, C, P, K, Ca, Mg, Fe, Mn, Cu, Zn的积累量。因此,栽培光氮条件N_(80%)Q_(4∶1)和采前LED红蓝光连续光照结合可以提高水培生菜营养元素含量。     

冠菌素和茉莉酸甲酯处理对金银花矿质元素影响研究

应用ICP-AES技术,测定并分析冠菌素和茉莉酸甲酯处理对金银花矿质元素含量、累积量和比例的影响。结果表明:(1)冠菌素处理使金银花K,Mg,Na,Zn,B,Si含量分别不同程度提高,P,Ca,Fe,Mn含量分别不同程度降低;(2)茉莉酸甲酯处理后金银花K,Na,Zn,B,Si含量分别不同程度增加,P,Ca,Mg,Fe,Mn含量分别不同程度降低;(3)冠菌素和茉莉酸甲酯处理后金银花K∶P和Na∶Zn升高,Ca∶Mg,Fe∶Mn,B∶Si降低。研究结果明确了冠菌素和茉莉酸甲酯处理对金银花矿质元素的影响,并为生长调节剂的合理使用提供科学依据。     

FAAS测定地梢瓜不同部位金属元素

采用HNO3-HClO4（4∶1）混酸消解地梢瓜的根、茎和叶,火焰原子吸收光谱法对消解液中的K、Ca、Na、Mg、Zn、Cu、Mn、Fe和Co9种金属元素进行了同时测定。获得了仪器测定的最佳工作条件、方法的准确性和精密度,结果显示：各元素平均加标回收率（n=6）为95.45%—102.26%,相对标准偏差（RSD,n=6）为0.18%—2.26%。地梢瓜不同部位各金属元素含量有一定差异,茎中Ca〉K〉Na〉Mg〉Fe〉Zn〉Co〉Mn〉Cu;叶中Ca〉K〉Na〉Mg〉Fe〉Co〉Zn〉Mn〉Cu;根中Ca〉K〉Fe〉Mg〉Na〉Zn〉Co〉Mn〉Cu。各部位均含有丰富的Ca、Mg、K、Na和Fe元素。测定方法快速、简单,准确度和精密度均较好,能达到分析要求。     

苦豆子不同生育时期矿质元素分析

应用ICP-AES等技术,研究了苦豆子常量、微量矿质元素含量、各部位吸收比例和不同时期的矿质元素需求量。结果显示:(1)成熟期苦豆子常量矿质元素比约为N∶K∶Ca∶Mg∶P∶Na=11.91∶8.27∶7.54∶1.02∶1.00,微量矿质元素比值约为Fe∶Zn∶B∶Cu∶Mn=28.91∶2.12∶1.40∶1.18∶1.00;(2)各器官矿质元素含量因生育时期存在差异,微量元素在营养期茎中总量最高占全株总量的45.6%,而在成熟期种子中最高占全株总量的36.7%。(3)苦豆子在营养期需肥最多,盛花期次之,盛荚期最少。     

火焰原子吸收光谱法测定中草药川东獐牙菜中的八种微量元素

用火焰原子吸收光谱法对川东獐牙菜中K, Ca, Na, Mg, Fe, Zn, Mn和Cu八种微量元素进行了分析测定。结果显示,用HNO₃-HClO₄(5∶1)混酸作消化液处理样品,精密度和回收率较好。在选定的实验条件下,川东獐牙菜各元素间相互不干扰,可在一份样品液中进行八种元素的分别测定。川东獐牙菜中含有较丰富的K,Ca和Na, 以及Mg和Zn,其含量K＞Ca＞Mg＞Na＞Zn＞Fe＞Cu＞Mn。方法的检出限均小于0.097 μg·mL-1,RSD≤2.34%(n=8),加标回收率89.32%～106.65%。     

原子吸收法建立舒筋活血中成药的无机元素的控制方法的探讨

人们已认识到无机元素与中成药的疗效有密切相关。但是在研究舒筋活血中成药化学成分的质量控制时, 无机成分常被忽视。 文章用原子吸收光谱法,测定了中成药大活络丸和几种中药中15种无机元素Cu, Ca, Fe, K, Mg, Mo, Ni, Sr, V, Mn, Zn, Na, Cr, Cd和Hg的含量, 探讨了无机元素与中药的药效关系,并通过大活络丸与几种中药所含无机元素含量的对照比较, 得出大活络丸中Fe, Cu, Mn和Zn等与药效之间的关系。中成药大活络丸中所含一定量的Fe, Cu, Mn和Zn等微量元素与其祛风除湿,理气豁痰,舒筋活络等药效存在一定关联。对大活络丸的无机元素测定与分析可为今后其指纹图谱的建立提供数据和参考依据。     

FAAS法测定地石榴中12种金属元素

采用浓硝酸∶高氯酸(4+1)常压微沸条件下消解地石榴样品,应用火焰原子吸收光谱法测定了地石榴中的金属元素Na、K、Mg、Ca、Fe、Co、Ni、Cu、Zn、Mn、Cd、Pb含量,研究了测定不同元素的仪器最佳工作条件、方法的准确性和精密度。结果表明,地石榴中Na、K、Mg、Ca、Fe、Cu、Zn、Mn、Cd含量分别为33.88,3444.54,328.54,1924.76,56.65,1.88,2.97,1.59,2.99mg.100g-1,Co、Ni、Pb未检出。方法的加标回收率为98.16%—103.6%,相对标准偏差(n=9)为0.21%—2.22%。测定方法简单易行,方便快捷,结果令人满意。     

Guided-Wave Two-Dimensional Acousto-Optic Scanner Using Proton-Exchanged Lithium Niobate Waveguide

Two-dimensional scanning of a 0.6328 mum guided-light beam has been realized using noncolinear acousto-optic (AO) coplanar Bragg diffraction together with colinear AO guided-mode to substrate radiation-mode conversion in a Z-cut Xpropagation LiNbO3 proton-exchanged (PE) waveguide. The two surface acoustic (SAW) waves utilized are at the center frequencies of 500 and 200 MHz, propagating in the Y and X axes, respectively. Two-dimensional scanning of approximately 720 resolvable light beam spots, namely, 18 40 (horizontal vertical) scanning, has been demonstrated using a light beam of 1.0 mm aperture. The total number of resolvable beam spots can be greatly increased from 720 by simply utilizing SAW transducers of larger bandwidth and a light beam of greater aperture. It should also be possible to significantly increase the diffraction efficiency from 3 % by optimizing the parameters of the PE waveguide and the SAWs.     

Effect ofγ-radiation on the spectral luminescence characteristics of impure cadmium tungstate crystals

Results of a study of the effect of γ-radiation on the spectral luminescence properties of cadmium tungstate crystals doped with silver, bismuth, and molybdenum cations are presented. Spectral characteristics of the nondnnnoped crystals are briefly described. Absorption and photo and X-ray luminescence spectra of the crystals taken before and after exposure to γ-radiation (5.5·10⁴ Gy) are compared. It is found that the spectral characteristics of the crystals doped with silver, bismuth, and molybdenum cations do not change markedly after the exposure. The relation between the type of impurity-induced defects, individual characteristics of the impurity cations, and the character of the effect of γ-radiation on the spectral luminescence properties of impure crystals is analyzed (preliminarily). Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 55–60, January–February, 1997.     

Femtosecond Transform-Limited Pulse Generation by Compensating for the Linear Chirp of SPM Spectra in Dispersion Shifted Fibers

A simple technique of pulse compression, based on the linear chirp compensation of self-phase modulation (SPM) spectra in dispersion shifted fibers, is demonstrated. The optimization procedure is carried out, for a short span of a single-mode fiber, using a parabolic law, which describes the behavior of the squared output pulse width versus the pump peak power in the case of Gaussian pulses. The experimental results give a minimum pulse duration of 233 fs, which is in good agreement with the model. Shorter and coherent pulses, down to 90 fs, have been obtained by inserting an interference filter at the optical output.     

Sorting of bending magnets for the SSRF booster

The Shanghai Synchrotron Radiation Facility(SSRF)booster ring,a full energy injector for the storage ring,is deigned to accelerate the electron beam energy from 150MeV to 3.5GeV that demands high extraction efficiency at the extraction energy with low beam loss rate when electrons are ramping.Closed orbit distortion(COD)caused by bending magnet field uniformity errors which affects the machine performance harmfully could be effectively reduced by bending magnet location sorting.Considering the affections of random errors in measurement,both ideal sorting and realistic sorting are studied based on measured bending magnet field uniformity errors and one reasonable combination of bending magnets which can reduce the horizontal COD by a factor of 5is given as the final installation sequence of the booster bending magnets in this paper.     

Measurement of nonlinear coefficient of optical fiber based on small chirped soliton transmission

We measure the waveform and phase curves of short optical pulses before and after transmission over different lengths of fibers by use of the pulse analyzer with the frequency-resolved optical gating (FROG),and numerically simulate pulse evolution under the experimental conditions.The nonlinear coefficient of the fiber is given by comparing the experimental results with the numerical ones.Difference between the experiment and numerical simulation is analyzed.     

Resonance scattering of canonical elastic shells in absorbing fluid medium

Resonance scattering of elastic spherical shell and cylindrical shell while the surrounding fluid medium has absorption is studied. The normal mode solution derived using exact elastic theory and the separation of variables is still applicable. However, the scattering form function has to be modified for the absorbing medium, otherwise the unreasonable result would be obtained. The backscattering form function in the absorbing medium is redefined, and the form function of elastic spherical and cylindrical shell with vacuum or solid matter filled is calculated in various absorption conditions. The results show that the absorption of surrounding fluid leads to notable attenuation of the coincidence resonances in the mid-frequency, but it has a little influence on the low-frequency resonance scattering induced by the filler inside the shell.     

Single-beam self-referenced phase-sensitive surface plasmon resonance sensor with high detection resolution

A versatile and low-cost single-beam self-referenced phase-sensitive surface plasmon resonance(SPR)sensing system with ultra-high resolution performance is presented.The system exhibits a root-mean-square phase fluctuation of ±0.0028.over a period of 45 min.i.e.a resolution of±5.2×10-9 refractive index units.The enhanced performance has been achieved through the incorporation of three design elements:a true single-beam configuration enabling complete self-referencing so that only the phase change associated with SPR gets detected,a differential measurement scheme to eliminate spurious signals not related to the sensor response,and the elimination of retardation drifts by incorporating temperature stabilization in the liquid crystal phase modulato .Our design should bring the detection sensitivity of non-labeling SPR biosensing closer to that achievable by conventional fluorescence-based techniques.     

Influences of SiO2 protective layers and annealing on the laser-induced damage threshold of Ta2O5 films

Ta2O5 films are prepared on BK7 substrates with conventional electron beam evaporation deposition.The effects of SiO2 protective layers and annealing on the laser-induced damage threshold (LIDT) of the films are investigated.The results show that SiO2 protective layers exert little influence on the electric field intensity(EFI)distribution,microstructure and microdefect density but increase the absorption slightly.Annealing iS effective on decreasing the microdefect density and the absorption of the films.Both SiO2 protective layers and annealing are beneficial to the damage resistance of the films and the latter is more effective to improve the LIDT.Moreover,the maximal LIDT of Ta2O5 films is achieved by the combination of SiO2 protective layers and annealing.     

A stereo matching algorithm using multi-peak candidate matches and geometric constraints

Gray cross correlation matching technique is adopted to extract candidate matches with gray cross correla- tion coefficients less than some certain range of maximal correlation coefficient called multi-peak candidate matches. Multi-peak candidates are extracted corresponding to three closest feature points at first. The corresponding multi-peak candidate matches are used to construct the model polygon. Correspondence is determined based on the local geometric relations between the three feature points and the multi-peak candidates. The disparity test and the global consistency checkout are applied to eliminate the remaining ambiguous matches that are not removed by the local geometric relational test. Experimental results show that the proposed algorithm is feasible and accurate.