Dipping methods

In the dipping method, the insects are picked up with a pair of forceps and dipped into the insecticide preparation, which is either a suspension or an emulsion. A dipping net or a screened container can also be devised for exposure of the insects for a few seconds. The dose is varied by increasing the concentrations in a series of beakers. After treatment, the insects are placed in clean containers and mortality counts are made after a suitable interval. 

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The scale can also be removed by shot blasting using abrasive grits such as dry sand, less than I mm (p. This method is more suited for components not suited to the dip method and cast iron components, in which the acid may become trapped in the porous surfaces. For sheet-metal components and complicated shapes and crevices, the dip method alone is recommended. 

The more automatic the method of coating application, the more economical and efficient it is, since automation lends itself more readily to more even coatings than do manual methods, e.g. large surface areas lend themselves more readily to spraying techniques, whereas open work structures are more suitable for dipping methods. The coating should also be applied to a specified minimum thickness which is adequate for the service conditions and life envisaged. 

Studies of pzc in mixed solvents were also carried out by Blaszczyk etal n using the dipping method. They worked in mixtures offormamide and NMF and estimated the shift of the standard potential of the hydrogen electrode, of the surface dipole potential atHg, and of the liquid junction potential. 

Caution o-Tolidine is very toxic and possibly carcinogenic For this reason the dipping method should be preferred. This is the only way to ensure that the spray mist does not reach the respiratory tract or skin. 

The molecular structure of a Cgo-Pst hyperbranched polymer can be described as in Fig. 20. Cgo-Pst hyperbranched polymer molecules were transferred onto mica chips by the vertical dipping method of L-B him techniques as introduced above. 

It has been shown that surface-modihed C5Q-Pst polymer was synthesized and was transferred onto mica chips by using the vertical dipping method of L-B film techniques. Though the surface was scanned many times, only a small amount of transfer could be found on the surface of the L-B Hlms. L-B films of C5Q-Pst polymer, even with only one layer, showed good microtribological performance. The topography and the order of the hlms are the most important factors influencing the microscale friction and wear. 

X-IP is useful to reduce the reaction between PFPE and AI2O3. In this test, a usual dipping method was used to prepare X-IP films on the surfaces of the head. The X-IP solution was diluted by 1 -methoxynonafluorobutane. The thickness of the X-1P film was controlled by adjusting the solution concentration and the time of the samples being immersed... 

Langmuir-Blodgett films were prepared by spreading a 2 x 1(T4 M solution of the enantiomerically pure helicenebisquinone in chloroform onto a water surface. After evaporation of the solvent, the monolayer was compressed to a surface pressure of 20 mN/m. After stabilization for 30 min, the monolayers were transferred by the horizontal dipping method onto glass substrates, treated with octadecyltrichlorosilane to make them hydrophobic. 

LB films of cadmium octadecanoate and other amphiphiles were transferred on a quartz-crystal microbalance (QCM, 9 MHz, AT-cut) as a substrate with a vertical dipping method. Frequencies of the QCM substrate were followed with time in air, after the QCM was raised from the interface. From the time courses of these frequency changes at each dipping cycle, the transfer amount of dry LB films (W ), the incorporated amount of water (W2), and its evaporation speed (v) could be obtained in nanogram level. 

Spread the mix by using a medicine dropper. Do not use disposable pipets The disposable pipets have extremely narrow openings at the end and they clog up easily. There exists a dipping method for preparing TLC slides, but since the usual solvents, methanol and chloroform (Caution Toxic ) do not activate the binder, the powder falls off the plate. Because the layers formed by this process are very thin, they are very fragile. 

Clavilier s currently recommended procedure is as follows. Two cooling processes of the crystal after flame-annealing treatment are carried out between steps (a) and (b) in Fig. 1 i.e., air cooling until the temperature of the crystal becomes 200-300°C and cooling in pure water under an H2 -I- Ar stream. The transfer of the crystal into the cell in step (c) of Fig. 1 with a droplet of H2 + Ar-saturated pure water on the crystal face is important for protecting the crystal surface from impurities in air. Then the crystal surface is exposed to the solution by the dipping method of Fig. 1. 

Today about one-third of all the zinc metal is used for the process known as galvanization. This process provides a protective coating of zinc on other metals. A thin layer of zinc oxidizes in air, thus providing a galvanic corrosion protection to the iron or steel item that it coats. Several processes are used to galvanize other metals. One is the hot dip method wherein the outer surface of the item to be galvanized is pickled and then immersed into a molten zinc bath. A... 

Fig. 11 Polarized absorption spectra of DNA /proflavine/2Ci8-glu-N LB films (88 layers) deposited by a vertical dipping method and b horizontal lifting method...

The DNA-aligned thin film could also be obtained with the LB method, in which anionic DNA strands were transferred with cationic monolayers at the interface using vertical dipping method. DNA was aligned along the dipping directions. 

Fig. 3.5.2 Schematic representation of the vertical dipping method of preparing LB films from compressed monolayers of fatty acids on aqueous subphases of divalent metal ions.

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