不同施肥期和施肥量对津川1号产量和食味品质的影响

以天津地区主栽的优质粳型水稻品种‘津川1号’为试验材料,研究施肥期和施氮量对水稻的产量、稻谷的常规品质、米粉的RVA特征值和米饭食味的影响。结果表明,不同施肥期和施氮量对产量,糙米率,垩白率,直链淀粉含量,RVA的峰值黏度、热浆黏度和消减值,米饭食味值各种指标上均有显著差异。在低氮处理和高氮处理中,时期一与其他两个时期相比,产量更高,稻米的碾磨品质、米粉的直链淀粉和蛋白质含量、RVA谱的特征值、米饭的外观和食味等理化指标都更为优异。因此,就‘津川1号’这一品种而言,水稻进入抽穗期应尽早施入穗肥。施肥时期一的产量最高,食味品质最好。     

拉布拉多犬的毛色遗传和繁殖选育

本文通过对影响犬被毛颜色色度的不同类型的黑色素,以及控制色素沉着的等位基因位点的深入分析探讨,了解和掌握拉犬毛色的表现型和基因型,以及B、b、E和e等位基因的遗传知识,就可以尝试利用谱系和后代的毛色信息确定父母本的毛色基因型,可以对拉犬的毛色进行所希望的繁殖选育,并可以预测后代中所有被毛颜色出现的比例。通过对色素修饰基因的分析探讨,了解和色素拉犬毛色的独特变化。     

Effects of dietary vitamin E and fat supplementation in growing-finishing swine fed to a heavy slaughter weight of 150 kg: II. Tissue fatty acid profile,vitamin E concentrations,and antioxidant capacity of plasma and tissue

The study aimed to assess the effects of vitamin E (VE) supplementation and fat source on fatty acid (FA) composition, VE concentrations, and antioxidant capacity in plasma and tissues of pigs fed to a heavy slaughter weight (150 kg). A total of 64 pigs (32 barrows, 32 gilts; 28.41 ± 0.83 kg) were blocked by sex and weight, and randomly assigned to one of eight dietary treatments (n = 8 per treatment) in a 4 × 2 factorial arrangement. Fat sources included corn starch (CS), 5% tallow (TW), 5% distiller’s corn oil (DCO), and 5% coconut oil (CN); VE supplementation levels were 11 and 200 ppm. Five-phase diets were formulated to meet requirement estimates of NRC (2012) and fed to pigs for each period of 25 kg from 25 to 150 kg. Increasing VE supplementation level increased C16:1 (P < 0.05) content but decreased C20:0 (P < 0.05) content in backfat and belly fat, while in liver, it increased C17:0 (P < 0.05) but decreased C18:0 (P < 0.05). Compared to the pigs fed the CS diet, the pigs fed the CN diet had greater (P < 0.05) content of total saturated FA, the pigs fed the DCO diet had greater (P < 0.05) content of total polyunsaturated FA content and iodine value, and the pigs fed the TW diet had greater (P < 0.05) content of total monounsaturated FA in backfat, belly fat, and liver. Plasma VE concentrations increased linearly (P < 0.05) with increasing length of feeding but faster (P < 0.05) in the pigs fed the CN and TW diets compared with the CS and DCO diets within the 200 ppm VE level; the pigs fed the DCO diet had the highest plasma VE concentrations (P < 0.05) from Phase 2 to Phase 5 within the 11 ppm VE level. The VE concentrations in liver and loin muscle (P < 0.05) increased with increasing dietary VE level from 11 to 200 ppm, but it was not affected by dietary fat source. There was no effect of VE supplementation and fat source on antioxidant capacity in plasma and liver except that pigs fed the DCO diet had greater liver SOD activity (P < 0.05) than the pigs fed the CN diet. In conclusion, dietary VE supplementation did not affect FA profile in backfat, belly fat, and liver consistently, while dietary FA composition with different fat sources affected much of the FA profile in backfat, belly fat, and liver. The higher level of VE supplementation increased liver and muscle VE concentrations and dietary fat sources affected plasma VE concentrations differently (P < 0.05), wherein the TW and CN diets increased the VE absorption greater than the DCO diet.     

近代时期豫西北农村庙会市场研究

庙会市场是农村市场的有机组成部分。近代以来,随着农村社会商品经济的发展,农产品商品化程度日益提高,乡村庙会分布随之日趋增多,集镇地区多有庙会,非集镇村落亦兴起庙会,同时庙会的商品交易功能也逐步增强。本文从农村庙会状况、组织管理、时间结构、个案分析、区域差异等几个方面分析了豫西北农村庙会市场的时代特点,以及其在地方农村市场体系中的重要作用。     

The effect of lactic acid bacterial starter culture and chemical additives on wilted rice straw silage

Lactic acid bacteria (LAB) are suitable for rice straw silage fermentation, but have been studied rarely, and rice straw as raw material for ensiling is difficult because of its disadvantages, such as low nutrition for microbial activities and low abundances of natural populations of LAB. So we investigated the effect of application of LAB and chemical additives on the fermentation quality and microbial community of wilted rice straw silage. Treatment with chemical additives increased the concentrations of crude protein (CP), water soluble carbohydrate (WSC), acetic acid and lactic acid, reduced the concentrations of acid detergent fiber (ADF) and neutral detergent fiber (NDF), but did not effectively inhibit the growth of spoilage organisms. Inoculation with LABs did not improve the nutritional value of the silage because of poor growth of LABs in wilted rice straw. Inoculation with LAB and addition of chemical materials improved the quality of silage similar to the effects of addition of chemical materials alone. Growth of aerobic and facultatively anaerobic bacteria was inhibited by this mixed treatment and the LAB gradually dominated the microbial community. In summary, the fermentation quality of wilted rice straw silage had improved by addition of LAB and chemical materials.     

支持向量机在高压绝缘子污秽程度评定中的应用

高压绝缘子污秽程度的评定可以表述为多类模式识别问题,由于影响绝缘子表面污秽状况的因素复杂,并且实际获得的样本数据有限,因此传统的智能方法往往达不到工程应用的精度要求。研究利用支持向量机在解决小样本、非线性及高维识别中的优势,将可用于多类模式识别的DAG SVM s模型用于高压绝缘子污秽程度的评定。该模型易于实现,且能够找到模式间的最优分类超平面,泛化能力较高。用SVM评定高压绝缘子污秽程度时,可以综合考虑不同污秽程度绝缘子泄漏电流的电气特性、环境参数与绝缘子污秽程度之间的非线性关系,从而实现具有极大模糊性的绝缘子表面污秽程度的评定。结果表明,此方法对解决绝缘子污秽程度的评定问题具有良好的适应性和实用性。     

3WZ-700型自走式果园风送定向喷雾机

针对现代果园低矮密植的种植特点,设计了3WZ-700型自走式果园风送定向喷雾机。通过理论计算和虚拟样机技术,完成整机结构设计和各关键部件技术参数的确定。设计了适应于低矮密植果园的圆环双流道风送雾化装置,确定叶轮直径0.7 m、出风口宽度0.13 m。实现风机转速0～2 000 r/min的无级变速。田间试验结果表明,树膛内部枝叶正、反面雾滴附着率分别为61.22%、20.90%;树膛外部枝叶正、反面雾滴附着率分别为77.22%、37.17%;作业效率为1.02 hm2/h。     

西花蓟马的生物学习性观察试验

在温室内以粉色玫瑰为寄主植物观察并记录了西花蓟马的部分生物学习性,在恒温箱内记录了在15℃、20℃、25℃、30℃4个温度下各虫态的历期,并计算出发育起点温度和有效积温.     

林麝饲养种群mtDNA遗传多样性和遗传结构分析

[目的]研究林麝饲养种群的遗传多样性现状及遗传结构,为指导种群遗传管理及其饲养种群种质保护与利用提供理论依据.[方法]遴选陕西省宝鸡市凤县的片仔癀麝场和逢春麝场,汉中市留坝县的太子岭麝场,采用分子粪便学的方法,采集220份新鲜的粪便样品,成功获得112条mtDNA控制区序列,计算单倍型多样性和核苷酸多样性.[结果]在3...