DSWT-FTIR-RBFNN鉴别罂粟和虞美人

采用水平衰减全反射傅里叶红外光谱法(HATR-FTIR)测定罂粟和虞美人的FTIR,由于两者为同科同属中药材,所含化学成分较为相近,为了更好地突出罂粟和虞美人在FTIR上的差异,并据此进行正确分类识别,利用离散平稳小波变换(DSWT)分别对罂粟和虞美人的种皮和种仁的FTIR进行若干尺度的变换,从中选择2个最具代表性的尺度作为特征提取的尺度空间.根据罂粟和虞美人的FTIR分布情况,确定将DSWT域内2个尺度的FTIR分别划分为2个特征区域并以每个区域内的光谱能量作为特征参数.从而构造一个包含8个特征参数的特征向量,将这个特征向量输入到径向基函数神经网络(RBFNN)进行训练,从而达到正确识别罂粟和虞美人的目的.实验中共取罂粟和虞美人的FTIR数据128对,其中训练样本78对,测试样本50对.实验结果表明利用文章的方法对罂粟和虞美人的正确识别率分别为99.8%和99.9%,从而验证了方法的有效性.     

“霍耳效应”实验教学探讨

籽做好霍耳效应教学实验，讨论了使用的磁铁或电磁铁的Ｂ值或励磁电流值和流经霍耳片的样品电流的选取原则，通过实例给出了具体数值。     

火焰原子吸收光谱测定花椒及椒皮、椒籽中钢、锌、铁、锰含量

用硝酸、高氯酸混合酸消解样品,原子吸收光谱法测定河南太行山区的花椒及椒皮、椒籽中铜、锌、铁、锰的含量,并对其结果进行了分析.结果显示:各元素在实验范围内,线性关系良好,回收率在92%-103%之间.花椒及椒皮、椒籽中均含有微量元素,花椒中铜、锌、铁、锰的含量分别为11.571、90.868、18.818、78.851μg·g-1,其中铁、锰含量丰富.铜、锌、铁的分布量为椒籽＞椒皮;锰的分布量为椒皮＞椒籽.测定结果为探讨花椒的高药用价值提供了有力的证据,椒籽中铜、锌、铁含量高于椒皮,应该大力开发利用.     

火焰原子吸收光谱测定花椒及椒皮、椒籽中铜、锌、铁、锰含量

用硝酸、高氯酸混合酸消解样品。原子吸收光谱法测定河南太行山区的花椒及椒皮、椒籽中铜、锌、铁、锰的含量。并对其结果进行了分析。结果显示：各元素在实验范围内。线性关系良好。回收率在92％-103％之间。花椒及椒皮、椒籽中均含有微量元素。花椒中铜、锌、铁、锰的含量分别为11．571、90．868、18．818、78．851μg·g^-1。其中铁、锰含量丰富。铜、锌、铁的分布量为椒籽〉椒皮;锰的分布量为椒皮〉椒籽。测定结果为探讨花椒的高药用价值提供了有力的证据,椒籽中铜、锌、铁含量高于椒皮,应该大力开发利用。     

紫外分光光度法检测VE对牡丹籽油抗氧化性的影响

采用紫外分光光度法检测不同添加量VE对牡丹籽油羟基自由基的抑制作用,探讨了VE的抗氧化活性,并研究了VE的抗氧化能力与还原力之间的关系,以筛选得到能够增强牡丹籽油抗氧化性能的VE最适添加量.结果表明：VE对羟基自由基有一定的清除作用,浓度为95mg/L的VE清除率达到20.54％;VE的最适添加量为95mg/L.VE对牡丹籽油具有明显的抗氧化作用,其抗氧化性与还原性之间是线性相关的.     

辣木籽的傅里叶变换红外光谱鉴别研究

利用傅里叶红外光谱仪对辣木籽、松子和火麻子进行傅里叶变换红外光谱和二维相关红外光谱研究。结果显示,辣木籽、松子和火麻子的FTIR光谱在1 800~700cm~(-1)范围有差异,光谱主要由油脂、碳水化合物和蛋白质峰构成。二维相关红外光谱在960~1 300cm~(-1)范围,辣木籽有6个自动峰,松子和火麻子有2个自动峰,自动峰强度差异较大。在1 400~1 780cm~(-1)范围,三者的同步谱中自动峰的数量、强度和位置都不同。结果表明傅里叶变换红外光谱结合二维相关红外光谱能够有效的区分辣木籽、松子和火麻子。     

以广义相对论为例谈实验检验的总体方案设计

以广义相对论为例，论述了如何根据物理理论的逻辑体系设计实验，以检验理论的正确性，对于广义相对论，检验实验应包括对等效原理的检验实验，对牛顿极限的检验实验，以及对广义相对论推论的检验实验。     

氢化物发生-原子荧光光谱法测定芹菜籽中的硒

本法采用湿法消解,氢化物发生-原子荧光光谱法测定芹菜籽中硒。研究了原子荧光光谱仪的参数和最佳试验条件,方法的线性方程为I=124.350C-21.041,相关系数r=0.9999,检出限为0.1007μg/L。结果表明,芹菜籽中硒的回收率在94.3%—111.1%之间。     

微波消解-火焰原子吸收光谱法测定皂荚中6种微量元素的含量

用浓硝酸微波消解样品,火焰原子吸收光谱法直接测定了皂荚、皂荚壳及皂荚籽中Fe、Cu、Mg、Ca、Mn、Zn6种微量元素的含量。皂荚、皂荚壳及皂荚籽中含有丰富的人体必需微量元素,采用此方法回收率在95.0%—105.0%之间。本方法简单、准确,结果令人满意。     

连续动力系统时间序列的非线性检验

用相位随机化的替代数据方法，研究了连续混沌动力系统时间序列的非线性检验判定.研究发现，在不同的采样情况下，混沌时间序列的非线性特性检验有所差异，尤其对于过采样时间序列，往往会出现虚假的判断结果.针对过采样时间序列，最好采用能够反映非线性特征的参数，作为检验统计量进行检验判断. 关键词： 替代数据 关联维数 连续时间序列 非线性检验     

大黄种子中蛋白质、多糖和淀粉含量的测定

采用凯氏定氮法、苯酚-硫酸比色法和双波长比色法测定唐古特大黄种子、掌叶大黄种子和药用大黄种子的蛋白质、多糖和淀粉的含量.采用凯氏定氮法测定蛋白质含量,苯酚-硫酸比色法测定多糖含量,双波长比色法测定淀粉含量.唐古特大黄种子的蛋白质和多糖在三种大黄种子中含量最高,分别为21.81％、6.58％,掌叶大黄种子淀粉含量在三种大黄种子中最高,含量为32.95％.三种大黄种子中,蛋白质含量为：唐古特大黄种子＞掌叶大黄种子＞药用大黄种子;多糖含量为：唐古特大黄种子＞掌叶大黄种子＞药用大黄种子;淀粉含量为：掌叶大黄种子＞唐古特大黄种子＞药用大黄种子.大黄种子的蛋白质、多糖、淀粉含量丰富.测定方法精密度、准确度、稳定性均符合生物样品测定要求,可用于大黄种子蛋白质、多糖和淀粉含量的测定.     

Germination, growth rates, and electron microscope analysis of tomato seeds flown on the LDEF

The purpose of the experiment was to determine cosmic rays long-term effects on living tissue. A batch of tomato seeds were flown in orbit aboard the Long Duration Exposure Facility (LDEF) for almost 6 y. During this time, the seeds received an abundant exposure to cosmic radiation. Upon the return of the LDEF to Earth, the seeds were distributed throughout the United States and 30 foreign countries for analysis. Our university analysis included germination and growth rates as well as scanning electron microscopy (SEM) and X-ray analysis of the control as well as space exposed tomato seeds.

In analyzing the seeds under the electron microscope, usual observations were performed on the nutritional and epidermis layer of the seed. These layers appeared to be more porous in the space exposed seeds than on Earth-based control seeds. This unusual characteristic may explain the increases in the space seeds growth pattern. (Several test results showed that the space-exposed seeds germinated sooner than Earth-based seeds. Also, the space-exposed seeds grew at a faster rate.) The porous nutritional region may allow the seeds to receive necessary nutrients and liquids more readily, thus enabling the plant to grow at a faster rate.

Roots, leaves and stems were cut into small sections and mounted. After sputter coating the specimens with argon/gold palladium plasma, they were viewed under the electron microscope. Many micrographs were taken. The X-ray analysis displayed possible identifications of calcium, potassium, chlorine, copper, aluminum, silicon, phosphate, carbon, and sometimes sulfur and iron. The highest concentrations were shown in potassium and calcium. As a result of the electron interaction and X-ray production within the open seeds, the traditional layers of the space-exposed seed gave peaks of Mg, P and S, while the Earth seed gave an iron peak, which was not detected in the space-exposed seed because of electron beam positioning difference. The space-exposed seed and the Earth-control seed specimens displayed high concentrations of copper.     

Beneficial effect of post -thawing osmoconditioning on the recovery of cryopreserved coffee (Coffea arabica L.) seeds

Osmoconditioning-controlled rehydration of seeds in a solution with low osmotic potential -has been shown to reinvigorate aged seeds. The present work aimed at investigating the effect of osmoconditioning on the germination of cryopreserved seeds of Coffea arabica, whose viability and vigour are drastically affected by cryopreservation. For cryopreservation, seeds were desiccated to 0.21 g H2O/g dw, cooled at 1 degree C/min to -50 degree C, then immersed rapidly in liquid nitrogen. After rapid rewarming, seeds were osmoconditioned for 1 to 6 weeks using solutions with osmotic potentials between -1 and -4 MPa. The time to produce half of the final percentage of normal seedlings, T50, was about three fold lower with osmoconditioned seeds than with non-osmoconditioned seeds (12-14 d vs 36 d). Moreover, after a 6-week osmoconditioning treatment with solutions with osmotic potential of -1 and -1.25 MPa, the percentage of seedlings recovered from cryopreserved seeds was 64-74%, against 13-16% only for cryopreserved seeds which were not osmoconditioned.     

Cryopreservation of immature seeds of Ponerorchis graminifolia var. suzukiana by vitrification

Ponerorchis graminifolia var. suzukiana is a terrestrial orchid that is an endangered species native to Japan, and it germinates more readily in immature seeds than in mature seeds. To preserve this orchid, an efficient protocol was established for the cryopreservation of immature seeds of P. graminifolia var. suzukiana. When immature seeds of 6 weeks after pollination, which showed higher germination and protocorm formation than mature seeds, were precultured on New Dogashima (ND) medium with 0.3M sucrose for 3 days and cryopreserved by vitrification method (treated with PVS2 for 60 min), the viability after preservation as assessed with 2,3,5-triphenyltetrazolium chloride staining test was about 86%. Immature seeds thus treated showed equal rates of germination and protocorm formation to the untreated control immature seeds, and they developed into normal plantlets on ND medium.     

New determinants for tolerance of coffee (Coffea arabica L.) seeds to liquid nitrogen exposure

The present work establishes for the first time that tolerance of coffee seeds to liquid nitrogen (LN) exposure depends on the initial quality of the seedlot and on the rewarming regime employed. Seedlot quality was estimated by the parameters of a quantal response model of desiccation sensitivity developed previously. The percentage of seedlings recovered from cryopreserved seeds was very well correlated with the relative humidity (RH) at which 90 percent of the initial viability was retained, RH90, as estimated by the model. Whatever the cooling regime employed, rewarming the seeds slowly by exposing them to ambient air was highly detrimental. Slow rewarming-induced viability loss was not due to imbibitional damage since seeds pre-heated at 37 degree C after slow rewarming to 0 degree C exhibited a survival percentage lower than seeds thawed rapidly to 0 degree C before sowing. The optimal hydration status for coffee seed cryopreservation was also re-examined. Drying seeds in 81 percent RH provided survival percentages considerably higher than those obtained using the drying RH always employed until now, i.e. 78 percent. A new procedure for slowly precooling the seeds prior to immersion in LN was also established. It consisted of placing the vials containing the seeds in a dry ice-bath for 25 min. Using this procedure in combination with seed drying in 81 percent RH and rapid rewarming in a 37 degree C water-bath for 30 min ensured the highest survival percentages ever obtained with coffee seeds, i.e. 89 percent, a value which was not significantly different from the initial viability percentage.     

Optical absorption coefficient of laser irradiated wheat seeds determined by photoacoustic spectroscopy

Present study is concerned with the photoacoustic (PA) assessment of optical absorption coefficient (β) for treated (soaking in the methylene blue dye) and untreated seeds of wheat. The determination of β, based on the Rosencwaig and Gersho model enables the optical absorption coefficient to be assessed directly from the measured amplitude of PA signal. The obtained β values were statistically analyzed. The outcome of the analysis shows significant differences in β values: in the wavelength range from 600 to 700 nm treated (with dye) seeds have higher β than untreated seeds. These seeds were also irradiated (varying time and intensity) with a laser diode emitting at 650 nm. Germination tests were carried out on both, irradiated and control (no irradiated) seeds. The percentage of normal seedlings from treated seeds was found higher (p ≤ 0.05) than from control seeds.     

Narrowing oF the critical hydration window for cryopreservation of Salix caprea seeds following ageing and a reduction in vigour

We investigated the effects of desiccation, rehydration and cryopreservation on the viability of seeds of a wild mountain species and seven clones of Salix caprea L. Seeds responded differently to all treatments depending on clone, seed initial moisture content (MC) and seed vigour. Fresh seeds of two randomly selected clones tolerated desiccation to MC 8.5-9.6 % FW (0.09-0.11 g water per g dry mass. g/gdw) without any noticeable loss in viability and were successfully cryopreserved at MCs ranging from 8.5 to 23.4 % (0.09-0.30 g/gdw). Storage at 5 degree C for approximately 10 weeks significantly reduced the viability of seed lots of a wild species and of three S. caprea clones, whilst viability of seeds of four other clones remained unaffected. Since all clones tested were genetically derived from one tree, this variation is unlikely to be of maternal origin. Most probably paternal x environmental factors have influenced seed behavior during desiccation and storage. As viability decreased due to partial ageing, seeds became more susceptible to desiccation stress. When seeds of three clones were cryopreserved, the hydration window for survival was wider for highly vigorous seeds (c. 0.05-0.28 g/gdw) than for seeds with intermediate vigour (c. 0.10-0.24 g/gdw) and low vigour (c. 0.20-0.37 g/gdw). Rehydration to MC above 0.15 g/gdw improved germination of low vigour seeds, both in controls and after cryopreservation. In contrast, cryopreservation of high vigour seeds rehydrated to MCs above 0.11 g/gdw resulted in a sharp decrease in normal seedling production. Whilst no effect of cryogenic temperature on germination and normal seedling production was observed when seeds of seven clones were cryopreserved within their hydration windows, the results indicate the need to account for seed lot vigour when designing cryopreservation protocols.     

In vitro study of magnetic nanoparticles as the implant for implant assisted magnetic drug targeting

Magnetic nanoparticle (MNP) seeds were studied in vitro for use as an implant in implant assisted-magnetic drug targeting (IA-MDT). The magnetite seeds were captured in a porous polymer, mimicking capillary tissue, with an external magnetic field (70 mT) and then used subsequently to capture magnetic drug carrier particles (MDCPs) (0.87 μm diameter) with the same magnetic field. The effects of the MNP seed diameter (10, 50 and 100 nm), MNP seed concentration (0.25-2.0 mg/mL), and fluid velocity (0.03-0.15 cm/s) on the capture efficiency (CE) of both the MNP seeds and the MDCPs were studied. The CE of the 10 nm MNP seeds was never more than 30%, while those of the 50 and 100 nm MNP seeds was always greater than 80% and in many cases exceeded 90%. Only the MNP seed concentration affected its CE. The 10 nm MNP seeds did not increase the MDCP CE over that obtained in the absence of the MNP seeds, while the 50 and 100 nm MNP seeds increased significantly, typically by more than a factor of two. The 50 and 100 nm MNP seeds also exhibited similar abilities to capture the MDCPs, with the MDCP CE always increasing with decreasing fluid velocity and generally increasing with increasing MNP seed concentration. The MNP seed size, magnetic properties, and capacity to self-agglomerate and form clusters were key properties that make them a viable implant in IA-MDT.     

Survival of four accessions of Anigozanthos manglesii (haemodoraceae) seeds following exposure to liquid nitrogen

This study investigated the survival of seeds from the prominent endemic Western Australian species Anigozanthos manglesii following exposure to liquid nitrogen (cryostorage). Seeds from four different accessions (collected in 1987, 1990, 1993 and 1998) adjusted to different water contents were tested for survival following cryostorage. Water content was a significant determining factor with survival of cryostored seeds declining rapidly at water contents above c. 18%. These water contents were deemed as critical water contents and were supported by DSC scans showing high endothermic peaks indicating ice crystallisation. In some instances, survival of cryostored seeds also declined at low water contents. Seeds from 1990 had a lower than expected survival compared to the other accessions. This may have resulted from the higher lipid content of seeds from this accession, or the reduced germination and vigour of these seeds prior to cryostorage.     

Shape-controlled synthesis of diamond crystal by epitaxial growth under high pressure and high temperature conditions

In this paper, the diamond epitaxial growth mechanism has been studied in detail by employing several types of diamond as a seed in a catalyst-graphite system under high pressure and high temperature (HPHT) conditions. We find that the diamond nucleation, growth rate, crystal orientation, and morphology are significantly influenced by the original seeds. The smooth surfaces of seeds are beneficial for the fabrication of high-quality diamond. Our results reveal that the diamond morphology is mainly determined by the original shape of seeds in the early growth stage, but it has an adjustment process during the growth and leads to well symmetry. Additionally, we have also established the growth model for the twinned diamond grown on several seeds, and proposed the possible growth processes by tracking the particular shapes of seeds before and after treatment under HPHT conditions. These results suggest that the shape-controlled synthesis of diamond with well morphology can be realized by employing certain suitable diamond seeds. This work is expected to play an important role in the preparation of trustworthy diamond-based electronic and photonic devices.