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1.
分析了扭矩标准机的工作原理和扭矩平衡机构的关键技术,从扭矩平衡驱动装置、配重平衡机构、支承的刀口和刀承选择、力臂杠杆锁紧机构及力臂杠杆自动平衡系统等方面进行分析,并从初负荷和最大负荷灵敏限的理论出发,分析了力臂杠杆组件结构性能的重要性,其对扭矩标准机杠杆平衡的影响很大,由此得出力臂杠杆组件对整机计量准确度的高低起到至关重要作用,可为相关领域的扭矩标准机关键技术研制及生产提供一定参考价值,具有良好的经济效益。  相似文献   

2.
电阻应变式轧制力传感器是现代钢铁企业中钢材轧制机常用的力传感器,轧钢机通过轧制力传感来测量轧辊两端的力值并对轧制力进行控制,其力值的准确度直接影响到钢材的成品率。本文介绍一种校准方法及其过程中分析其不确定度分量主要来源,并对各不确定度分量、合成不确定度、扩展不确定度进行评定。  相似文献   

3.
随着我国医疗水平的不断提高,计量检定标准规范化、制度化发展,B超机在我国医疗诊断中的使用范围越来越广,因此B超机的计量检定显得尤为重要。在B超机的计量检定过程中要综合考虑计量测量的不确定度,以保证测量结果的准确性与科学性。本文先是对计量测量不确定度进行概述,又详细阐述了计量测量不确定度在医院计量检测中的应用,最后分析介绍了计量测量不确定度在B超机计量检定中的应用。  相似文献   

4.
微波消解-火焰原子吸收法测定貉毛中铜含量方法的准确度和精密度良好,通过分析影响测量不确定度的主要来源,对分析过程中的样品称量、样品前处理、标准溶液配制、标准曲线非线性引入的输入值、测量重复性和仪器本身等6个不确定分量进行分析和合成,计算出铜的扩展不确定度,为系统分析检测结果的准确程度和方法的可靠性提供参考。  相似文献   

5.
试验旨在探讨检测过程中各因素对畸形率检测结果准确性的影响。试验建立测量不确定度模型,通过检测种猪常温精液精子畸形率,针对主要影响种猪精子畸形率可靠性的因素进行分析,建立种猪精液品质检测结果可靠性评估的方法。结果显示,测量标准不确定度结果为0.84%,扩展不确定度结果为1.68%。研究表明,生物投影显微镜的分辨率对精子畸形率检测的准确度影响较小,配制吉姆萨染色液浓度不影响检测结果,操作人员的技术水平对不确定度分量的结果影响较大。  相似文献   

6.
通过对饲料中盐酸克伦特罗测定过程中样品的称重、提取、标准溶液的配制、内标的配制和添加、标准曲线的建立等因素进行分析研究,并建立了数学模型。结果表明:标准溶液和内标的配制、样品的处理、标准曲线等对检测的不确定度贡献最大,而电子天平称重影响较小。分析得出被测量(饲料中盐酸克伦特罗)的合成标准不确定度u(cx)=0.229mg/kg,取包含因子k=2,则扩展不确定度分别为0.459mg/kg,测量结果的表述为(130.07+0.459)mg/kg,真实的反映了测量的置信度和准确度。  相似文献   

7.
本文分别从二等标准铂电阻温度计的分度传递引入的标准不确定度、标准铂电阻温度计不稳定引入的标准不确定度、电测设备引入的标准不确定度、冰点槽和油槽不均匀温场引入的标准不确定度、测量重复性引入的标准不确定度分析评定了工业铂电阻测量结果的不确定度。  相似文献   

8.
亚硝酸钠标准滴定溶液浓度的不确定度评定   总被引:1,自引:1,他引:0  
建立了亚硝酸钠标准滴定溶液浓度标定的不确定度评定方法。通过建立数学模型,找出影响不确定度的因素并对各个不确定度分量进行评估。计算各分量的不确定度,由此计算合成不确定度,最终给出了亚硝酸钠标准滴定溶液浓度的扩展不确定度和置信水平。测量不确定度可用于对亚硝酸钠标准滴定溶液浓度标定结果的评估。  相似文献   

9.
本文分别从二等标准铂电阻温度计的分度传递引入的标准不确定度、标准铂电阻温度计不稳定引入的标准不确定度、电测设备引入的标准不确定度、冰点槽和油槽不均匀温场引入的标准不确定度、测量重复性引入的标准不确定度分析评定了工业铂电阻测量结果的不确定度。  相似文献   

10.
为全面评价显微硬度测量结果的准确性,本文通过兽医注射针硬度试验对显微硬度测量结果不确定进行了评价,分析了检测过程中不确定度的来源,根据极差公式等方法合成标准不确定度,并计算扩展不确定度。  相似文献   

11.
The number of donkeys and mules throughout the world is stable, and awareness of their use and concern for welfare, pain recognition and treatment are receiving increasing veterinary interest. Therefore, accurate information about anaesthesia and analgesia in donkeys and mules is important to ever more equine practitioners. Since donkeys are physiologically and pharmacologically different from horses, knowledge on species specific aspects of anaesthesia and analgesia are very important. Mules combine elements from both donkey and horse backgrounds, leading to great diversity in size, temperament and body type. Physiologically, they seem to resemble horses more than donkeys. This review highlights the current knowledge on various anaesthetic and analgesic approaches in donkeys and mules. There is still much information that is not available about donkeys; in many circumstances, the clinician must use available equine information to treat the patient, while monitoring carefully to observe for differences in response to therapy compared to the horse.  相似文献   

12.
13.
The large intestine of 10 cows was examined from the right abdominal wall with a 3.5 MHz linear transducer. The cows were then slaughtered, and the organs were re-examined in a water bath. The caecum was visualised from the middle region of the abdominal wall. It ran caudo-cranially, varied in diameter from 5.2 to 18.0 cm and was situated immediately adjacent to the abdominal wall. The lateral wall of the caecum appeared as a thick, echogenic, crescent-shaped line. It could be visualised as far cranially as the 12th intercostal space. Although its junction could not be identified, the proximal ansa of the colon was recognised on the basis of its anatomical position and its diameter, which was smaller than that of the caecum. The spiral ansa of the colon and the descending colon were situated dorsal to the caecum and could be identified by moving the transducer horizontally along the abdominal wall to the last rib. The spiral ansa of the colon was situated ventral to the descending colon, and its walls appeared as thick echogenic lines. In a contracted state, the spiral colon had the appearance of a garland.  相似文献   

14.
Ethological studies are important means to evaluate the behaviour of small laboratory animals (mouse, rat, guinea-pig and rabbit) and their housing conditions. At any rate, the only sparse range of body expressions, the smallness and preference of night activity of these animals and the erratic occurrence of essential behaviour patterns make the investigations more difficult. On the other hand, the standardization of laboratory housing and the genetic definition of these animals turn out to be favourable. By this way, behaviour-environment-relationships are suitable for evaluation. Taking into consideration methodical and biological restrictions, the specific activities such as fight, relaxed resting behaviour and play as well as unbalanced behaviour patterns and stereotypes can be taken as means of evaluation. Particularly in mice and rabbits, upright position and space consuming activities will be possibly restricted by cage sizes.  相似文献   

15.
Effects of age and diet composition on amylase, trypsin and chymotrypsin activities in the pancreas and intestinal contents, pancreas weights and body weights were determined from birth to 56 d. A total of 120 pigs, five to seven pigs/litter from 18 litters, were slaughtered at birth, 14, 27, 29, 31, 42 and 56 d. Litters were allotted to dietary treatments (corn-soy, A; corn-soy + 20% dried whey, B; corn-soy + 5% lard, C) and offered these diets as creep feed at 14 d. All pigs were weaned at 28 d, placed in elevated nursery pens and fed their respective diets. Total activities of amylase, trypsin and chymotrypsin in the pancreas and small intestine increased (P less than .05) with age. Both trypsin and amylase activities, measured per kilogram body weight or gram pancreas weight, were low at 29 d in the intestine and increased to 56 d. Pigs on diet B had the highest level of trypsin and chymotrypsin in the intestinal contents (P less than .05). Trypsin activity in the pancreas (units/kg body weight) was lowest (P less than .05) for pigs on diet B and highest (P less than .05) for those on diet C (units/g pancreas and units/kg body weight). Amylase activity (units/kg body weight) was lower (P less than .05) in the pancreas for pigs on diet B than for those on diets A and C. Pigs on diet A had lower (P less than .01) intestinal amylase activities than those on diets B and C. Enzyme activities in the intestinal contents and pancreas were low following weaning. In the pancreas, activities decreased at 31 d.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

16.
Blood and urine samples of 180 dairy cows from 12 herds were examined. Sodium and potassium concentrations were determined in erythrocytes, whole blood, plasma, urine, and glucose concentration in blood: the interrelations were compared. Sodium and potassium concentrations in erythrocytes were 85.15 +/- 11.45 mmol/l, and 25.93 +/- 7.81 mmol/l, respectively. A statistically significant relation was found between sodium and potassium concentrations in erythrocytes (r = 0.3467+++) and the content of electrolyte in blood cells and in whole blood (Na: r = 0.5336+++; K: r = 0.3561+++). No statistically significant relation of intraerythrocyte concentration of both electrolytes was confirmed with respect to the other characteristics (sodium and potassium concentrations in plasma and urine, and glucose concentration in blood). In the conditions of routine laboratory diagnostics in clinically healthy cows, determinations of intraerythrocyte sodium and potassium do not broaden possibilities of evaluating the metabolic state of these electrolytes and cannot be used as the characteristics of energy insufficiency. The cannot replace the analyses performed in serum and urine.  相似文献   

17.
The rate of flow of fluid from the caecum and from the large colon was measured in four Shetland-type ponies fed a hay diet. In two ponies with cannulas in the caecum and at the origin of the right ventral colon, a continuous intracaecal infusion of a solution of chromium EDTA was used and samples were obtained from the cannula at the origin of the right ventral colon. Based on four determinations, the liquid flow from the caecum was 54.2 +/- 1.89 litres d-1. In the other two ponies with cannulas in the origin of the right ventral colon and near the end of the right dorsal colon, a continuous infusion of chromium EDTA was made into the right ventral colon and samples were obtained from the right dorsal colon. The flow rate towards the end of the dorsal colon was 49.4 +/- 1.25 litres d-1, based on four determinations. The capacities of the caecum and large colon after death were 7.0 +/- 0.8 and 17.7 +/- 3.7 litres, respectively.  相似文献   

18.
本文应用Fortana—Masson嗜银颗粒染色法研究了貉、蓝狐、银狐的胃及十二指肠内嗜银细胞的形态分布。结果表明:三种动物胃幽门腺中,嗜根细胞数量最多,呈锥状,嗜银颗粒较粗,密度大、染成深黑色。在胃底及胃贲门腺区、嗜银细胞数量少。在十二指肠部嗜银细胞呈蝌蚪形,嗜银颗粒细,呈黑褐色,密度较小。嗜银细胞的分布密度在三种动物中具有一定的差别。  相似文献   

19.
The maximal conduction velocities of compound-action potentials in the proximal and distal parts of the saphenous nerve were determined by averaging potentials evoked and recorded through needle electrodes. Antidromic, triphasic compound-action potentials unipolarly recorded from the distal part of the saphenous nerve were of the same minimal latency as potentials having 4 phases which were recorded bipolarly from the same site. However, the unipolarly recorded potentials were of greater amplitude. Monophasic compound-action potentials were recorded through bipolar chlorided silver electrodes from the surface of fascicles of the distal part of the saphenous nerve. The maximal conduction velocity of these potentials was in agreement with the conduction velocity of compound-action potentials of the distal part of the saphenous nerve which were evoked and recorded through subcutaneous needle electrodes. The specificities of the stimulating and recording sites were verified by recording before and after the saphenous nerve was cut between the stimulating and recording sites. Mean conduction velocities were 62.3 +/- 2.0 m/s for the distal part of the saphenous nerve and 66.3 +/- 2.2 m/s for the proximal part of the saphenous nerve. Reflex-evoked muscle activity was elicited in the ipsilateral tensor muscle of the fascia lata and semimembranous muscle after electrical stimulation of the saphenous nerve through subcutaneous needle electrodes. The effects of various stimulus intensities on the latency and duration of these reflex-evoked muscle potentials were determined.  相似文献   

20.
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