INFLUENCE OF DESIGN AND OPERATING PARAMETERS ON THE POWER CHARACTERISTICS OF THE GREENHOUSE SOIL REMOVAL AND LOADING MACHINE

Выращивание овощей в теплицах позволяет собирать частые урожаи и круглогодично обеспечивать население свежей продукцией. В последнее время, особенно с развитием органического земледелия, наряду с гидропонной широко используется грунтовая технология, при которой растения выращиваются на специально приготовленных почвенных смесях, состоящих из естественных природных компонентов. Использование этой технологии предполагает периодическую замену верхнего (санитарного) слоя почвы в теплицах. Специализированных машин для выполнения операции по удалению санитарного слоя практически не существует, а для выполнения этой технологической операции в хозяйствах используют неприспособленные машины и оборудование. Для выполнения данной операции предложена новая конструкция прицепной машины для удаления и погрузки почвы. Приведены результаты экспериментальных исследований влияния режимных параметров на энергоемкость процесса удаления и погрузки почвы, а также установлен характер зависимости мощности, необходимой на привод машины, от режимных параметров. Полученные результаты позволили установить фактические значения режимных параметров, при которых значения энергоемкости и мощности примут рациональные величины, что позволяет установить эффективность предложеннойконструкции машины, тем самым, полностью механизировать процесс удаления ипогрузки почвы в теплицах. Growing vegetables in greenhouses allows having frequent harvests and provides the population with fresh produce year-round. Nowadays, especially with the development of organic farming, along with hydroponic farming, soil technology is widely used, plants being grown on specially prepared soil mixtures consisting of natural components. The use of this technology involves the periodic replacement of the upper (sanitary) soil layer in greenhouses. There are practically no specialized machines for performing the operation to remove the sanitary layer, and unadapted machines and equipment are used to perform this technological operation on farms. To perform this operation, a new design of a trailed machine for removing and loading soil has been proposed. The results of experimental studies of the influence of operating parameters on the energy intensity of the process of removing and loading soil are presented, and the nature of the dependence of the power required to drive the machine on operating parameters has been established. The results obtained made it possible to establish the actual values of the operating parameters at which the values of energy intensity and power take rational values, which makes it possible to establish the effectiveness of the proposed machine design, thereby completely mechanizing the process of removing and loading soil in greenhouses.

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Application of Improved Voltage Compensation in the SEM to Imaging of Organic Materials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100072666 ◽

1973 ◽

Vol 31 ◽

pp. 444-445

Author(s):

P.J. Killingworth ◽

M. Warren

Keyword(s):

Electron Beam ◽

Organic Materials ◽

Operating Parameters ◽

Low Density ◽

Beam Diameter ◽

Incident Electron Beam ◽

Specimen Material ◽

Voltage Compensation ◽

Selection Of ◽

Scanning Electron

Ultimate resolution in the scanning electron microscope is determined not only by the diameter of the incident electron beam, but by interaction of that beam with the specimen material. Generally, while minimum beam diameter diminishes with increasing voltage, due to the reduced effect of aberration component and magnetic interference, the excited volume within the sample increases with electron energy. Thus, for any given material and imaging signal, there is an optimum volt age to achieve best resolution.In the case of organic materials, which are in general of low density and electric ally non-conducting; and may in addition be susceptible to radiation and heat damage, the selection of correct operating parameters is extremely critical and is achiev ed by interative adjustment.

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Electron sources: Past, present, and future

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100149659 ◽

1993 ◽

Vol 51 ◽

pp. 764-765

Author(s):

David C Joy

Keyword(s):

Glass Tube ◽

Source Size ◽

Electron Gun ◽

Operating Parameters ◽

Operational Parameters ◽

Electron Sources ◽

Difficult Decision ◽

Probe Size ◽

Wide Range ◽

Overall Performance

The electron source is the most important component of the Scanning electron microscope (SEM) since it is this which will determine the overall performance of the machine. The gun performance can be described in terms of quantities such as its brightness, its source size, its energy spread, and its stability and, depending on the chosen application, any of these factors may be the most significant one. The task of the electron gun in an SEM is, in fact, particularly difficult because of the very wide range of operational parameters that may be required e.g a variation in probe size of from a few angstroms to a few microns, and a probe current which may go from less than a pico-amp to more than a microamp. This wide range of operating parameters makes the choice of the optimum source for scanning microscopy a difficult decision.Historically, the first step up from the sealed glass tube ‘cathode ray generator’ was the simple, diode, tungsten thermionic emitter.

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