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101.
[目的]探索葡萄糖酸亚铁固体脂质纳米粒的制备方法。[方法]采用两步W/O/W乳化方式制备葡萄糖酸亚铁固体脂质纳米粒(SLN)。以包埋率为指标,研究内外相、油水相体积比,卵磷脂浓度对SLN包埋率的影响。[结果]试验确定当内相中水相与油相的体积比为0.2,外水相与内相乳状液的体积比为5∶1,卵磷脂浓度为5%时,SLN的包埋率取得最大值,为52.48%。在内水相引入海藻酸钠(1∶2,W/W)的结果表明,SLN的包埋率增大,为59.03%,粒径、Zeta电位和多分散系数发生变化。体外释放试验表明,SLN能起到保护葡萄糖酸亚铁经受胃酸环境的作用,并在模拟肠液中表现为突释的释放效果。[结论]固体脂质纳米粒对葡萄糖酸亚铁有较好的保护及释放效果,可为无机铁补充剂的生产提供新的技术手段。  相似文献   
102.
通过分析8≤ Z≤100偶偶原子核电四极矩跃迁强度 B(E2:0+→2+)与2+态激发能 E(2+)实验数据,提出了原子核电四极矩跃迁强度新经验公式 B(E2:0+→2+)=33.65 Z2 A -0.71 E-1(2+).  相似文献   
103.
集中饮用水源地是三峡库区内易受事故型水污染影响的重要敏感目标,本文以集中饮用水源地为研究对象,开展三峡库区事故型水污染敏感目标辨识研究.研究结果表明:三峡库区内事故型水污染敏感目标(集中饮用水源地)共有99个,主要分布在重庆库区,为700余万人提供饮用水服务,其中服务人口10万人以上(包含10万)的集中饮用水源地有18个,重庆市九龙坡区、沙坪坝区、江北区和南岸区等区县内集中饮用水源地服务人口的数量较多;三峡库区共有特大敏感目标23个,重大敏感目标28个,二者占敏感目标总数的51.52%,且主要分布在三峡库区重庆段.  相似文献   
104.
该文将微教育模式引入乒乓球教学之中,以期改善乒乓球课堂的教学效果。首先,对微教育模式的实施过程进行了分析,将其明确为5个环节:调研学习需求、制定教学方案、设计教学内容、履行教学实践、反馈教学评价。其次,构建了基于微教育模式的乒乓球教学框架,并分析了微教育模式对乒乓球教学的影响。其次,对2个班级的乒乓球教学分别采用传统模式为微教育模式。实践结果表明,微教育模式全面提高了学生的乒乓球技能,使得学生在垫球、发球、正手攻杀、反手推挡、弧圈球、多回合球等技术上都有了较大进步。最后,给出了进一步推动乒乓球教学工作的3点建议。  相似文献   
105.
教师创新教育能力与培养创造型人才有着必然的联系。把科研与教研实践于“材料化学”课程教学,实现了良好的教学效果。在教案中将科研与教研的结合具体化,并把教师的科研成果直接应用于实际的教学中,使学生的知识更加系统化,开阔了学生的视野,增大了学生的知识面;通过对科研方法及成果的了解,加强了学生的创新意识、创新精神和创造能力的培养。  相似文献   
106.
Staphylococcus aureus and coagulase-negative staphylococci (CNS) isolated from bovine mastitis were examined for their ability to interact with 125I-labelled fibronectin, fibrinogen and type II collagen. Their relative surface hydrophobicity and production of extracellular capsule were also investigated. Almost all S. aureus strains bound fibronectin (mean value 23%), fibrinogen (mean value 12%) and type II collagen (mean value 16%). CNS bound fibronectin (mean value 6%) and type II collagen (mean value 7%), but not fibrinogen (mean value 2%). The specificity of binding of these proteins to S. aureus strain F1440 and to coagulase-negative Staphylococcus chromogenes strain BO52 was studied by adding an excess of unlabelled proteins. Fibronectin and collagen binding were observed to be specific, varying between 50 and 75%, whereas the specificity of fibrinogen binding to S. aureus strain F1440 was lower (26%). Most of the S. aureus strains (63%) showed very high surface hydrophobicity (autoaggregation) or lower hydrophobicity (29% of the strains) and the rest were hydrophilic. None of the CNS strains autoaggregated, 44% were classified as hydrophilic strains. Hydrophilic strains (except the reference strains) did not show extracellular capsule production. However, the encapsulated (reference) strains showed low binding to these proteins as compared to their unencapsulated variants. Pre-treatment of S. aureus strain F1440 and S. chromogenes strain BO52 with trypsin decreased their fibronectin binding capacity and surface hydrophobicity, whereas pre-treatment with bovine milk (except on collagen binding to strain F1440) did not significantly affect binding to these proteins. These data indicate that S. aureus and CNS isolated from bovine udder infection have the ability to bind to tissue matrix and plasma proteins which may be exposed in the traumatized or toxin-damaged udder epithelial lesions.  相似文献   
107.
Japanese farmers manage their irrigation water based on their past experiences and preferences, considering such factors as weather and available water (hereafter defined as empirical water management). They elaborately control the intake and drainage rates of their own paddy fields to maintain optimal ponding depths. But these well-managed systems will drastically change because of the decreasing number of farmers. Therefore, it is necessary to clarify if the optimal ponding depth will be maintained within the limits of traditionally-allowed water intake rate from the main river. The first objective of this study was the quantification of actual water use in the paddy fields, resulting from the farmers water management on the basis of their experience. The significance of the present water intake rate under empirical water management was studied for a paddy field command area of about 230 ha. Water intake rates and the water requirements of the whole area were investigated by measuring the flow rate at 17 points of irrigation and drainage canals. Characteristics of the farmers empirical water management were investigated by measuring the hourly changes in inflow and outflow rates for a sub-area using an automatic measurement system, and an inferential method of determining water management patterns for the paddy fields was proposed. The newly-proposed inferential method was introduced in the tank model, which expresses the characteristics of water management in the command area. The Shuffled Complex Evolution Algorithm (SCE-UA) method was used for optimizing the model parameters. It was proven that the model accuracy improved when the farmers empirical water management was taken into account. The optimal amount of water to be applied to the command area was quantified by the simulation. The second objective was to predict the effect of the decreasing number of farmers on future water use conditions. The simulated result indicates the difficulty of maintaining optimal ponding depth for the whole command area when the farmers empirical water management is not maintained. In other words, results indicated that efficient water use requires an automatic water management system or a new pipeline system to replace the farmers present empirical water management.  相似文献   
108.
109.
In this study, the effects of less-expensive protein sources replaced with soybean meal on growth performance, nutrient utilization and body composition of juvenile grass carp were investigated. For this purpose, a control diet containing 42% soybean meal was prepared. Cotton seed meal (CSM), sunflower meal (SFM) and corn meal (CM) were added to the experimental diets by replacing 100% of the soybean meal protein used in the control diet. All diets were iso-nitrogenous (40% crude protein) and iso-caloric (19.5?MJ?kg?1 gross energy). Each treatment had three replicates, and 20 juvenile grass carps (3.5?±?0.1?g, initial weight) were located in per replicate. The fish were fed to satiety three times in a day during 3?months at 26°C of water temperature in glass aquarium (45 l). The results of the study showed that the weight gain (308.6?C448.6%), specific growth rate (1.56?C1.89%/day), feed conversion rate (1.2?C1.9), protein efficiency ratio (1.32?C2.08), and apparent digestibility coefficients of protein (80.5?C89%) or sum of amino acids (80.5?C88.9%) were not significantly affected by the experimental diets, except diet CM. All of these values obtained for the diet CM were significantly lower than those of fish fed on the control, CSM and SFM diets. However, there were no significant differences between the lipid digestibility of the diets, and crude protein, lipid, and gross energy contents in the whole body of fish in experiments. In conclusion, CSM and SFM diets were highly utilized by juvenile grass carp, but not CM diet. These results combined with the remarkable acceptability of diets containing high levels of plant protein ingredients with identical growth performances of juvenile grass carp show clearly that dietary soybean meal level can be considerably reduced without any adverse consequence in terms of somatic growth and nitrogen utilization.  相似文献   
110.
The effects of artificial diets on growth and body condition of adult cuttlefish, Sepia officinalis were tested in two experiments. Supplemented prepared diets (fish myofibrillar protein concentrate) were fed during a 30-day and a 21-day experiments. Growth, feeding rate and food conversion of group-reared cuttlefish were analyzed. The first of these experiments tested four artificial diets, made with increasing levels of lysine, on adult cuttlefish. According to the chemical analysis, diets 1–3 had limiting concentrations of lysine and other essential amino acids (compared to mantle composition of the cuttlefish), while diet 4 was the only one where almost all essential amino acids were present in concentrations similar or higher than the ones present in cuttlefish mantle. A second experiment was conducted by isolating 16 adult cuttlefish individually, and feeding them the same four artificial diets, in order to obtain individual data. During Experiment 1, only the diet with the best chemical score (diet 4) produced growth (p < 0.05), with a mean instantaneous growth rate (MIGR) of 0.30% wet body weight (BW) d−1. Similarly, individually reared cuttlefish fed diet 4 produced the highest IGR’s (0.26, 0.38 and 0.48% BW d−1) and grew larger (p < 0.01). Comparison of cuttlefish fed the artificial diets vs. thawed shrimp and unfed cuttlefish indicated that cuttlefish fed the artificial diets were in an intermediate state. Growth rates obtained with the artificial diets (<0.4% BW d−1) were considerably lower compared to natural prey, live or frozen, reported by other authors.  相似文献   
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