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31.
32.
The aim of this paper is to analyze how the EU Water Framework Directive complies with the international principles concerning Integrated Water Resources Management (IWRM) agreed in major conferences. The outcomes of the International Conference on Water and Environment (Dublin, 1992), the Second World Water Forum (The Hague, 2000), the International Conference on Freshwater (Bonn, 2001), and the World Summit on Sustainable Development (WSSD) (Johannesburg, 2002) were compared with the EU Water Framework Directive. Seven notable mismatches were found, even though several EU countries have played a leading role in those conferences. The question arises whether the outcome of these conferences is not efficient enough to influence EU policies—do the conferences just produce collections of idealistic buzzwords or is there a requirement for different principles regarding IWRM for developing countries and developed countries?  相似文献   
33.
Stanley plums were processed into purees and then pastes by heat concentration to 25 and 300 Brix. The Brix of these two pastes was increased to 40 and 450, respectively, by sugar addition. Pastes were stored at 4 and 22 ± 2C in the dark for up to 24 weeks. Physical-chemical characteristics and microbiological quality were determined at 4 week intervals. Sensory evaluation was conducted at 0 and 24 weeks. Total solids, water activity, rheological properties and microbiological quality were stable during storage. Total acid, total anthocyanins, total pectin and Hunter ‘L’ and ‘a’ values decreased significantly during storage (P < 0.01). The degradation rate of total anthocyanins was much higher for pastes stored at 22C than those at 4C. Hue angle and Hunter ‘b’ values increased during storage. Sensory evaluation indicated that pastes were still acceptable after 24 weeks of storage.  相似文献   
34.
A mathematical model is presented for the current-voltage characteristic of a class of negative-resistance devices. The model is in a form compatible with digital computer languages, which makes it useful for the computer-aided analysis and design of electronic circuits incorporating such devices. The model needs three parameters extracted easily by hand calculations, without recourse to conventional curve-fitting techniques or iteration procedures  相似文献   
35.
鄂尔多斯盆地氦气资源丰富,已在伊盟隆起、伊陕斜坡南部等地区发现高含氦、富氦天然气田,这些气田的氦气富集多与断裂发育密切相关。然而,盆地内的构造背景较为复杂,为研究盆地内不同地质背景下氦气的富集特征及控制因素,对鄂尔多斯盆地伊陕斜坡东北部开展天然气组分分析测试,并结合研究区基础地质资料及前人研究成果,对鄂尔多斯盆地神木气田上古生界的氦气分布特征及其地质影响因素进行探究。神木气田上古生界氦气含量达0.017%~0.116%,平均氦气含量为0.05%,达到含氦气田标准;氦气含量在平面上呈“西低东高”的整体分布格局,东部部分地区的氦气含量大于0.1%;氦气含量与氮气含量呈明显正相关关系,表明天然气藏中的氦气和氮气在成因和溶解—脱溶机制上可能存在必然联系。神木气田氦气的富集受多种地质因素共同影响:上古生界广泛分布的煤系烃源岩提供了充足的氦气;地壳抬升和构造反转控制了氦气的运移方向,且促进了溶解氦的脱溶和聚集;适量的载体气有助于氦气的富集。结合研究区构造背景和氦气成藏地质因素,提出了一种新的氦气富集模式,即斜坡—沉积源岩型含氦天然气富集模式,这为氦气勘探和开发工作提供了重要的理论支持。  相似文献   
36.
针对高维数据含有的冗余特征影响机器学习训练效率和泛化能力的问题,为提升模式识别准确率、降低计算复杂度,提出了一种基于正则互表示(RMR)性质的无监督特征选择方法.首先,利用特征之间的相关性,建立由Frobenius范数约束的无监督特征选择数学模型;然后,设计分治-岭回归优化算法对模型进行快速优化;最后,根据模型最优解综...  相似文献   
37.
    

In rice, high concentration of lead (Pb) can cause phyto-toxicity affecting several physiological functions. Cultivation of rice varieties that are resistant to Pb-induced oxidative stress is an important management strategy in Pb-contaminated soils. In the current study, we evaluated four different rice cultivars for their response to Pb-induced stress. Three japonica type cultivars X-Jigna, Ediget, and Furat, and one Indica type cultivar Amber 33 were grown in soil containing different Pb concentrations (0 mM, 0.6 mM, and 1.2 mM). The soil was treated with 0 mM or 0.6 mM or 1.2 mM Pb solution one month prior to rice seedling transplantation. Thereafter, four-week-old rice seedlings were transplanted into the treated soil and their responses were observed until maturity. The data revealed that a highest concentration of Pb (1.2 mM) induced significant reduction in agronomic traits such as plant height, number of tillers per plant, number of panicles per plant, and number of spikelets per panicle in all the rice cultivars. However, least reduction in the agronomic traits was observed in X-Jigna, whereas the highest reduction in the agronomic traits was observed in Ediget. Antioxidant activity of catalase (CAT), peroxidase (POD), polyphenol oxidase (PPO), and superoxide dismutase (SOD), was evaluated along with the accumulation of superoxide ions (O2.-), protein, proline, chlorophyll, sucrose, glucose, and fructose contents in all the rice cultivars. A significant increase in antioxidant activity and in the accumulation of proline and sucrose contents with the least reduction in the chlorophyll and protein contents was observed in X-Jigna suggesting that X-Jigna is the most tolerant among all the rice cultivars tested against Pb-stress. On the other hand, non-significant and slightly significant increase in the antioxidant activity, less accumulation of proline and sucrose contents, and higher reduction in the chlorophyll and protein contents was observed in Ediget, which further suggest that Ediget is the most susceptible rice cultivar to Pb-stress. In addition, the other rice cultivars Furat and Amber 33, were found to be moderately tolerant to Pb-induced oxidative stress. In summary, our results suggest that tolerance to Pb-induced oxidative stress would be a result of a synergetic action of both enzymatic and non-enzymatic antioxidant systems, leading to a balanced redox status in rice.

  相似文献   
38.
    
Polymorphism of kappa‐casein (κ‐CN) gene in three Bos indicus cattle breeds was investigated using a polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) technique. Only genotypes AA and AB were observed, and no BB, AE, BE, EE, AC or BC genotypes were detected in the three cattle breeds. In the Sahiwal, Cholistani and Red Sindhi breeds, the frequencies of the allele A were 0.69, 0.90 and 0.86, and the frequencies of the allele B were 0.31, 0.10 and 0.14, respectively. The Sahiwal breed was found to have a higher frequency of the AB genotype as compared to the Cholistani and Red Sindhi breeds. The frequency of the κ‐CN alleles noted in the three cattle breeds was similar to those observed in other cattle breeds of B. indicus origin.  相似文献   
39.
    

ABSTRACT

Gluten, “cohesive, viscoelastic, proteinaceous material prepared as a by‐product of the starch isolation from wheat flour” and the storage and dough‐forming protein of wheat flour, is the key to the unique ability of wheat to suit the production of leavened products. Wet gluten was only affected by wheat varieties, while dry gluten was affected by wheat varieties, crop years and their interaction. The wet and dry gluten ranged 8.0–43.13% and 2.58–14.55%, respectively, and were positively correlated with Zeleny value, sodium dodecyl sulfate sedimentation value and falling number. The gluten content was higher in Pavon, SA 42 and Faisalabad 85, while Zeleny value was higher in GA 02 and C 518, resulting in better gluten quality. Zeleny value was negatively correlated with crude protein content (r = –0.1857*). The lowest amount of wet and dry gluten was detected in Triticale and durum wheats as compared to common wheats. Zeleny value and sedimentation value may be used as indicators of gluten content and quality while working on wheats. The information thus collected will be valuable for cereal chemists and wheat breeders for improvements in their future breeding programs.

PRACTICAL APPLICATIONS

This research work will be a breakthrough and helpful for wheat breeders, growers, millers and bakers for their intended uses as every consumer demand specific wheat quality characteristics for their end products.
  相似文献   
40.
本文考虑一种基于最大后验概率算法的迭代相位同步方案。在经典方法中,相位噪声估计模型在信道和接收器的每个符号处考虑一个样本。但是,信息理论研究建议在信道和接收器的每个符号上使用多个样本以实现更高的性能。在本文中,得出了一种软信息辅助迭代接收器,该接收器使用现成的块进行检测和解调,以保持接收器的复杂性可接受。在这里,我们以务实的范例考虑每个符号在信道和接收器处的两个样本。结果表明,以适度的处理开销为代价,可以显著改善相位噪声估计。给出了针对低密度奇偶校验编码的正交幅度调制的仿真结果。结果表明,与传统的接收器方法相比,强相位噪声值具有显著的性能改善。  相似文献   
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