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991.
光对红肉桃果肉红色形成的影响   总被引:3,自引:0,他引:3  
为探讨光照是否影响红肉桃果实果肉着色,以青岛市地方红肉桃品种“大把撸”为材料,研究了不同套袋处理对着色后红肉桃果肉糖酸及色素尤其是花青苷含量变化的影响。结果表明:套袋明显抑制了果肉红色的形成;果实摘袋见光后花青苷合成能力得到恢复;套袋也降低了红肉桃果肉可滴定酸、可溶性糖、叶绿素和类胡萝卜素含量,由此证明红肉桃果实果肉红色形成在很大程度上受光照影响。  相似文献   
992.
棉花叶绿体基因组的研究进展   总被引:1,自引:0,他引:1  
近年来,随着分子生物学技术的应用与发展,对棉花叶绿体基因组也有了新认识。本文概述了棉花叶绿体基因组的研究进展,从棉花叶绿体基因组的图谱、功能基因的克隆及研究、叶绿体RNA编辑以及叶绿体转化等方面进行了介绍和评述,并对其在基础研究与应用研究中的前景进行了展望。  相似文献   
993.
山竹是一种常见的热带植物,富含黄酮类、多酚、蛋白质和脂类。因其良好的抗氧化活性,以及抗菌,抗炎及抗过敏的功效,日益受到医药学界的重视,其提取物在国外已产业化,并应用于食品及化妆品行业。介绍了目前国内外对山竹的化学成分、抗氧化活性、抗菌活性、抗炎及抗过敏、增强免疫及抗肿瘤等方面的研究进展,旨在加深对山竹的诸多有效化学组分研究,并充分结合临床,尽快用于治疗和预防相关疾病。  相似文献   
994.
胶东果园土壤酸度特征及酸化原因分析   总被引:7,自引:2,他引:7  
通过对胶东地区果园土壤的采样化验,并与全国第二次土壤普查的数据对比分析.结果显示,果园土壤酸化程度明显高于第二次土壤普查和农田土壤,果园上层土壤pH值和潜性酸低于下层,酸化明显。化肥的过量施入、有机肥施用不足、大水漫灌的灌溉方式是加剧果园土壤酸化的主要原因。  相似文献   
995.
植物生长调节剂是一种特殊的含有植物激素活性的农药,能够起到改善农作物质量和控制植物生长的作用,近年来植物生长调节剂的毒性及其残留危害吸引了众多研究人员的关注。其中,矮壮素(CHLM)和缩节胺(MEP)作为常用的2种植物生长调节剂,其使用不当和残留危害所引起的食品安全问题并没有引起足够的重视。最近的研究工作将CHLM和MEP确立为大麦麦芽烘烤过程的副产品,而用于研究的大麦属于生态类型,经验证不含任何植物生长调节剂。由此可知,CHLM和MEP是由食品中的天然成分经过热加工处理后形成的化合物。CHLM和MEP作为新的食品加工污染物已成为食品安全问题的研究热点。对CHLM、MEP在食品中的形成进行了综述,并对其检测技术进行总结,以期为CHLM和MEP的研究提供参考。  相似文献   
996.
以马齿苋、黑豆和苦荞麦等为原料,经过发酵和炒制等工艺开发出了一种风味马齿苋野菜酱。以感官评分为指标,通过单因素试验和正交试验确定了干马齿苋的蒸制时间为10 min,大豆油用量为40 g,白砂糖用量为3.55 g,同时确定了马齿苋野菜酱的最佳配方。在此条件下制备的马齿苋酱风味浓郁、无异味;颜色呈暗红色、明亮,口感酸甜适口;汁液均匀、无分层和沉淀。  相似文献   
997.
Structure has a major influence on the stress strain relation of soil, which implies that the constitutive model should reflect the its structure. Based on the investigation , the over consolidation (OC) of the soils was made up of two different types, which were structure induced OC and stress induced OC. And then the structure induced OC and stress induced OC were united. Structure induced OC index was used to represent the degree of structure and the cam clay model was extended. The shape of the yield surface was the same as cam clay model, whise the size was equal to the sum of the structure induced OC and stress induced OC. And the change in size of the yield surface was decerminated by the volume harden function and the structural damage function. The associated flow rule was adopted in the model. Afterwards constitutive model for structured clays was presented. The concept of the model is clear and the parameters are simple. The ability of the model is good by firstly application and it can describe the character of the structured soils.  相似文献   
998.
A three stage series operational pilot scale constructed wetland was built for domestic wastewater treatment with inflow of 4.5 m3/d .The mass balance method was adopted to quantify the transportation and transformation of pollutants in constructed wetland during steady state operation.It was shown that the average removal rate of CODcr was 87.14%, in which 68.45% contributed by dissimilation and 18.69% contributed by assimilation.The average removal rate of TN was 60.21% and the contributions of denitrification and microbial assimilation or plant assimilation were 53.64%, 5.39% and 1.18%, respectively.The average removal rate of TP was 59.36% and the contributions of substrates absorption and microbial assimilation or plant assimilation were 43.55%, 12.26% and 3.55%,respectively.In conclusion, microorganisms played a key role in the removal of pollutants and substrates adsorption was the main approach to phosphorus removal.  相似文献   
999.
This paper focuses on the design of eleven rollers straightener. An elastic plastic FEM model is introduced to cope with the difficulty of pre estimating the performance of straightening during the design process. To obtain straightening force, stress, strain, elastic plastic ratio, relations between reduction amount of roller and roughness of plate per square meter, a three dimensional element model is established and straightening process is simulated. In addition, an experiment is conducted to measure the reduction amount of roller and the roughness of plate per square meter. It is shown that the results of numerical simulation are consistent with the experimental results. The developed computing model can provide essential references for the optimization of straightener.  相似文献   
1000.
Focusing on the problem that affine transformation will exist among the contour images due to variation of the viewpoints, a new approach to extract affine invariant features and matching strategy is proposed for shape recognition. First, the centroid distance and azimuth angle of each boundary point are computed. Then, with a prior defined angle interval, all the points in the neighbor region of the sample point are considered to calculate the average distance for eliminating noise. After that, the centroid distance ratios(CDRs) of any two contour points with angle difference of 180° are achieved as the representation of the shape, which would be invariant to affine transformation. Since the angles of contour points changed non linearly among affine related images, the CDRs should be resampled to build corresponding relationship. It could be regarded as an optimization problem of path planning. In our method, a PSO based path planning model is presented to address this problem. The experimental results demonstrate the efficiency of the proposed method in shape recognition with translation, scaling, rotation, distortion and noise interference.  相似文献   
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