罐顶对罐壁应力的影响     

陈湘球 《油气储运》1994,(4)

在大型油罐设计中采用线性理论的方法,分析论述了罐顶对罐壁是否产生影响这一问题。通过对拱顶油罐、浮顶油罐的罐壁边界条件、罐顶边界条件的分析计算,求出各层壁板挠度方程中的待定系数,便可得出其应力。从线性方程中,可看出影响罐壁应力的主要因素是挠度方程中的待定系数。待定系数除受储罐尺寸、液位高度的影响外,还受罐顶重量、罐顶剪力和弯矩的影响。以10万m~3浮顶油罐和拱顶油罐为例,进一步证明,液位是罐壁应力的控制因素,而罐顶重量、罐顶剪力和弯矩对罐壁应力的影响可以忽略不计。  相似文献   

固支矩形底扁球壳的边界几何缺陷     

蔡松柏  王选民 《湖南农业大学学报(自然科学版)》1991,18(3)

In this paper, concept of boundary geometrical imperfection during postbuckling process for shallow spherical shell is first presented. The effects of the declination of the rectangular boundary on postbuckling process are also studied by integrated metho  相似文献   

江西板栗疫病发生规律的研究   总被引：5，自引：1，他引：4  

游春平  唐祥宁 《江西农业大学学报》1995,17(1):13-16

  相似文献   

鸡蛋消毒方法的对比研究   总被引：3，自引：1，他引：3  

刘会珍  李刚  孙瑞国  高振江 《中国家禽》2005,9(Z1):170-173

采用5种消毒方法对鸡蛋蛋壳表面细菌进行杀菌效果试验,结果表明,各处理组之间抑菌效果差异显著(P＜0.05),杀菌效果优劣依次为开水浸烫＞甲醛熏蒸＞过氧乙酸熏蒸＞高锰酸钾浸泡＞过氧乙酸浸泡,开水浸烫操作技术难度较大,容易引起蛋壳破裂,适宜实际生产的消毒方法为过氧乙酸熏蒸和甲醛熏蒸.将消毒处理后的鸡蛋在温度25℃,相对湿度60%～80%贮存20天,开水浸烫处理组鸡蛋仍保持较鲜的品质,其余各组鸡蛋品质较差.结果表明,常规消毒方法(除开水浸烫法)只能抑制蛋壳表面微生物的生长繁殖,不能延缓鸡蛋品质下降达到保鲜鸡蛋的作用.  相似文献   

Assessing exterior egg quality indicators using machine vision     

A. V. Vasileva  E. V. Gorbunova  A. S. Vasilev  V. S. Peretyagin  A. N. Chertov  V. V. Korotaev 《British poultry science》2018,59(6):636-645

ABSTRACT

1. The objective of this study was to develop a machine vision method for analysing exterior parameters of chicken eggs to automate the stage of primary sorting.

2. The developed algorithm based on predetermined thresholds calculated egg quality indicators, including geometric dimensions, shape index and the mottling grade. The algorithm was implemented with an experimental setup that combined the image-based and the candling methods. A total of 400 egg samples were analysed.

3. Comparison of results of the algorithm with those obtained using the traditional manual method showed that mean value of radii values difference was 0.095 ± 0.058 mm for the sharp and 0.080 ± 0.047 mm for the blunt end of the egg, with standard deviations of 0.58 mm and 0.49 mm, respectively.

4. The correlation coefficient between the shape index values determined by the two methods was 0.93; the standard deviation of absolute differences between corresponding values was 1.05%.

5. The results of mottling grade estimation were compared using F-measure and confusion matrix.

6. The results allow the possibility to perform the assessment of egg exterior quality factors in an automatic mode, independent of the expertise of a grader.  相似文献   

放牧压力对草原砂质栗钙土微生物量C,N,P影响的研究     

孙秀英 《农业机械化与电气化》2014,(5):11-12

对不同放牧压力下草原砂质栗钙土微生物量C、N、P进行较为系统地研究。结果表明：就土壤原土来看,随着放牧压力的增大,土壤微生物量C,N先增加后减少;土壤微生物量C在放牧率2.67只羊/hm2时相对较高,微生物量P随着放牧压力的增大逐渐降低。  相似文献   

基于茶籽壳代替木屑栽培茶树菇配方筛选试验     

魏云辉  李菁  胡中娥  王洪秀  熊小文 《中国食用菌》2014,(5):30-32

不同比例的茶籽壳和木屑组合成5个试验配方,比较不同配方对菌丝生长、子实体经济性状和生物转化率的影响。试验结果表明,在供试的5个配方中,配方4（棉籽壳50%、茶籽壳15%、木屑5%、麦麸20%、玉米粉7%、石膏1%、磷肥1%、石灰1%）为优选配方。  相似文献   

Effects of Oyster Shell Soil Amendmenton Fruit Auality and Soil Chemical Properties in Greenhouse Tomato Acidic Soils     

《农业科学与技术》2016,(9)

[Objective]The aim was to explore the feasibility of applying oyster shell soil amendment for tomato production in order to determine proper quantity of the soil conditional.[Method]Field tests were performed to research effects of the soil conditioner on tomato yield,quality and soil p H.[Result]The results showed that tomato yield increased in the treatment groups with oyster shell soil amendment.The group SC50 increased the most by 16.5%than the control group.Based on normal fertilization,tomato growth was promoted by the soil amendment,and per tomato weight and lycopene content both improved during peak-fruiting period.Besides,soil p H value was enhanced by the soil amendment also.[Conclusion]It can be concluded that the effect was the best when soil conditioner was applied at 750 kg/hm2.  相似文献   

我国橡子资源的开发利用   总被引：1，自引：0，他引：1  

张玥  谢文霁  杨可心  李德海  杨冰雨  林岩 《中国林副特产》2014,(4):85-88

橡子营养丰富，而且具有多种功能特性，广泛应用在食品和其它工业中。对橡子仁、橡子皮质和橡子壳的成分、功能和应用等研究情况进行了综述，并介绍了橡子资源在食品及其它工业领域的应用进展，以及提出了橡子资源开发与研究过程中遇到的问题和解决方案。  相似文献   

Effects of Calcium Source and Calcium Level on Growth Performance,Immune Organ Indexes,Serum Components,Intestinal Microbiota,and Intestinal Morphology of Broiler Chickens     

《The Journal of Applied Poultry Research》2020,29(1):106-120

  相似文献