Rubber tapping machine performance and procedure

Abstract Rubber tapping is a rubber latex extraction process which has to be done early morning in order to satisfy cool climate for latex flow. It is a tedious process which takes great work force and man-hour it has to be done with great accuracy. It is a great necessity for an automated or mechanized tapping to cope with the market requirement. So it is required to design a Rubber tapping machine which should be affordable to small planters.

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Porous Epoxy: Effect of Mixing Sequences (ELH versus EHL) Using Toluene as Extraction Medium via Ultrasonic Technique

International Journal of Polymer Science ◽

10.1155/2016/4385626 ◽

2016 ◽

Vol 2016 ◽

pp. 1-5 ◽

Cited By ~ 2

Author(s):

Siti Noorkhartina Ishak ◽

Pei Leng Teh ◽

Uy Lan Du Ngoc ◽

Cheow Keat Yeoh

Keyword(s):

Dielectric Constant ◽

Flexural Strength ◽

Porous Structure ◽

Natural Rubber Latex ◽

Extraction Process ◽

Ultrasonic Technique ◽

Epoxy System ◽

Rubber Latex ◽

Mixing Sequences ◽

Density Results

Porous epoxy was fabricated using natural rubber latex (NRL) as the void template. In this study, two mixing sequences were selected: epoxy, hardener, and then latex (EHL) and epoxy, latex, and then hardener (ELH). The extraction process was carried out to extract the latex particles from the cured epoxy sample using toluene as extraction medium with ultrasonic technique for 1 hour. The formation of porous structure in epoxy system is dependent essentially on the amount of latex removed from the epoxy matrix. As expected, the density results showed lower values in the porous epoxy in ELH mixing sequences. More porous structure in epoxy was obtained which was proven by the increasing in porosity % which has led to lowering of the value in dielectric constant which is preferred for electronic packaging application. However, it also caused a decrease in flexural strength and modulus.

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Freeze-Etch Crystal-Like Structures in Membranous Glomerulosclerosis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100063883 ◽

1969 ◽

Vol 27 ◽

pp. 394-395

Author(s):

Burton B. Silver

Keyword(s):

Electron Microscopy ◽

Light Microscopy ◽

Sodium Hypochlorite ◽

Kidney Tissue ◽

Extraction Process ◽

Donor Kidney ◽

Unknown Substance ◽

Etched Surface ◽

Standard Fixation ◽

Diseased Kidney

Tissue from a non-functional kidney affected with chronic membranous glomerulosclerosis was removed at time of trnasplantation. Recipient kidney tissue and donor kidney tissue were simultaneously fixed for electron microscopy. Primary fixation was in phosphate buffered gluteraldehyde followed by infiltration in 20 and then 40% glycerol. The tissues were frozen in liquid Freon and finally in liquid nitrogen. Fracturing and replication of the etched surface was carried out in a Denton freeze-etch device. The etched surface was coated with platinum followed by carbon. These replicas were cleaned in a 50% solution of sodium hypochlorite and mounted on 400 mesh copper grids. They were examined in an Siemens Elmiskop IA. The pictures suggested that the diseased kidney had heavy deposits of an unknown substance which might account for its inoperative state at the time of surgery. Such deposits were not as apparent in light microscopy or in the standard fixation methods used for EM. This might have been due to some extraction process which removed such granular material in the dehydration steps.

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The Biological Clock and Sleep in the Elderly

Zeitschrift für Gerontopsychologie & -psychiatrie ◽

10.1024/1011-6877.19.1.45 ◽

2006 ◽

Vol 19 (1) ◽

pp. 45-51 ◽

Cited By ~ 1

Author(s):

Myriam Juda ◽

Mirjam Münch ◽

Anna Wirz-Justice ◽

Martha Merrow ◽

Till Roenneberg

Keyword(s):

Circadian Rhythms ◽

Biological Clock ◽

The Elderly ◽

Early Morning ◽

Behavioral Changes ◽

Older Age ◽

Age Related ◽

Theoretical Considerations ◽

Sleep Difficulties ◽

Circadian Biology

Abstract: Among many other changes, older age is characterized by advanced sleep-wake cycles, changes in the amplitude of various circadian rhythms, as well as reduced entrainment to zeitgebers. These features reveal themselves through early morning awakenings, sleep difficulties at night, and a re-emergence of daytime napping. This review summarizes the observations concerning the biological clock and sleep in the elderly and discusses the documented and theoretical considerations behind these age-related behavioral changes, especially with respect to circadian biology.

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