慢速螺旋输送机的功率探讨

慢速螺旋输送机的功率探讨武汉食品工业学院庞美荣所谓慢速螺旋输送机，是指水平式及低倾角倾斜输送的螺旋输送机。此类输送机因其工作时轴的转速较低且低于临界转速，故称其为慢速。它的功率计算通常采用下式：然而，上述公式计算出的轴功率与实际所配功率有较大的出入（...     

饲料螺旋输送机设计参数的选择和确定

<正>螺旋输送机是一种常用的不具有挠性牵引构件的连续输送机械,利用工作构件即螺旋的旋转运动,使物料向前运送,是现代化生产和物流运输不可缺少的重要机械设备之一。螺旋输送机在国民经济的各个部门中     

强力带式输送机的研制与应用

超大功率高速强力带式输送机主要是指输送带强度达到ST4500N,是集国内外输送机先进技术而设计、制造、安装调试,可以用动态分析软件对各种工况进行精确的分析和计算,并依照分析的结果作为以后工作的总体布置、结构设计和零件选型等工作的依据,保证了设计的可靠性和先进性。本文在理论的基础上,结合当前科学技术的发展,重新评估了强力带式输送机的工作原理、结构特点和优缺点。     

CL-100型热风烘茧机的研制与应用试验

蚕茧的茧层是缫丝工业的重要原料.干燥蚕茧的目的除普通物料干燥都具有除去水分,以利贮存保管的共性外,还要求在烘干过程中既要除去茧层、蛹体的自由水分,又要保留茧层一定的平衡水分,保护茧层的良好解舒,使丝胶适当变性,合理地增加煮茧抵抗力,符合缫丝要求.因此,蚕茧干燥工艺要求干燥过程温度由高到低;湿度由小到大,后阶段适当保湿;风速由大至小变化.国内现有蚕茧干燥设备大多采用73型灶或热风灶,烘茧质量较差.     

物料压缩率对长距离绞龙输送的影响

文章提出了物料压缩率的概念,针对物料压缩率的特性对长距离绞龙的影响作出了分析,并且对长距离绞龙由于物料压缩率问题引起的堵料提出了解决方案。     

Principles of screw and plate fixation

Understanding both the benefits and the limitations of screw and plate fixation, while considering the ultimate objective of returning the limb to full function, ensures acceptable and repeatable results. The basic principles of fracture repair using plating techniques are no more complicated than those applied to more "simple" methods using pin, wire, and external skeletal fixation; however, familiarity with the additional necessary instrumentation and technical aspects are required.     

The opioid haemorphin-7 in horses during low-speed and high-speed treadmill exercise to fatigue

The opioid neuropeptide haemorphin-7 was measured, by immunoreactivity, in Standardbred horses during low-speed (7 m/s) and high-speed (10 m/s) endurance exercises, lasting 49-58 and 12-16 min respectively. In parallel, heart rate, muscle temperature and plasma lactate concentrations were measured. The profile of the low-speed exercise showed significantly increased heart rate after 10 min [154 beats per minute (bpm)]. After the exercise, muscle temperature (42.1 degrees C) and plasma lactate (4.8 mmol/l) were significantly increased. The profile of the high-speed exercise was comparatively characterized by a higher increase of heart rate after 5 min (194 bpm) and higher increases of muscle temperature (43.2 degrees C) and lactate levels (15.8 mmol/l) after the exercise. The horses were probably exhausted by glycogen depletion in the low-speed exercise and by muscle pH decrease in the high-speed exercise. Haemorphin-7 increased significantly during the high-speed exercise (274.8 fmol/ml) but not during low speed (108.3 fmol/ml), coincident with the results of lactate. These results suggest that plasma haemorphin-7 is measurable in the horse by immunoreactivity, and that intense exercise stimulates release of this opioid. Such endogenous opioids are most likely involved in regulatory functions associated with pain, physical effort, inflammation, and blood pressure variation in horses, as have been established in other species.     

螺旋叶片的下料及加工方法

<正>随着饲料工业的蓬勃发展,各大、中、小型饲料生产厂家生意蒸蒸日上。螺旋输送机,由于其占地面积小,生产效率高,能进行任何角度的输送等特点为各饲料生产厂家广泛利用。少则几台,多则十几台,车间里总少不了这一产品。     

Doppler sonographic measurements of arterial blood flow and their repeatability in the equine foot during weight bearing and non-weight bearing

In six normal adult horses, pulsed-wave Doppler sonographic inspections were made of the left and right lateral palmar proper digital artery (LPPDA) of each thoracic limb. Using a two-period, crossover design with repeated measures, each LPPDA was inspected on four occasions throughout the day over a 7 hour period and, on each occasion, with the limb weight bearing and non-weight bearing. In comparison with the observations made during weight bearing, there were significant increases (P<0.001) in blood-flow velocities when the limb was non-weight bearing. There was no relationship between blood velocities and the time of day, the order in which the inspections were made, resting heart rate, age of the horse, or hoof angle. In both weight bearing and nonweight bearing, the Doppler waveform demonstrated a systolic peak followed by at least two diastolic peaks and an end diastolic plateau. Horses that moved least during sonographic inspections had the lowest co-efficients variation.     

Unnatural selection and survival of the fittest

Extract

It is significant that only 13 of nearly 400 delegates Who attended World Conference III on Breeding Endangered Species in Captivity listed themselves as having veterinary qualifications. For many people, a representation of just over 3 percent would seem to be par for the course when it comes to veterinary involvement with wildlife, for it is well-known that the majority of the profession have been trained to tend domestic animals and, whilst expressing a concern for wildlife, freely admit their incompetence to deal with it. Yet it is interesting to find that many of the world's leading zoo directors and curators have a veterinary background, and have been accepted by their zoologist counterparts as being at least their equals, if not their betters. Consequently, whilst veterinarians represent only a small proportion of the work force in zoos and wildlife parks, their influence is considerable.     

单螺杆和双螺杆挤压膨化机的一般比较

随着双螺杆挤压膨化机应用领域的拓宽。双螺杆挤压膨化机也开始用于宠物、水产、特种经济动物和幼畜哺乳期等饲料加工生产。然而。我国现有的饲料加工仍以单螺杆挤压膨化机为主。主要是由于进口双螺杆挤压膨化机成本太高。而国产双螺杆挤压膨化机技术性能和质量等方面尚有不足,也缺乏针对饲料工业特点应用的大产量机型。尽管从单螺杆和双螺杆的挤压膨化原理及机体结构分析就可看出双螺杆挤压膨化机具有明显的优势并具有更好的性价比。但相对于食品加工业的应用仍要逊色得多。近年来。随着国内企业引进、消化吸收国外先进技术。国产双螺杆挤压膨化机生产技术水平不断提高。特别是针对水产饲料生产推出了双螺杆挤压膨化专用机型,使得用投资单螺杆挤压膨化机的资金同样可以选用双螺杆机型。