Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Bulbs, holes

Several forms of apparatus employing electrical heati iig wi 11 be described. A simple form may be readily constructed from a domestic electric iron of 400-500 watts rating. The handle is removed, and two holes of 8 mm. diameter are drilled through the base (ca. 11 mm. thick) so that they meet in the centre of the block. One hole is for a 360° thermometer (small bulb) the other hole is spare and can be used for comparison with a standard thermometer. The heater is mounted on a sheet of thick asbestos board which is fixed to an appropriate wooden base. The wires from the heating unit are connected to two insulated terminals fitted on the board (Fig. 11, 11, 1). The rate of heating is controlled by either of the following methods ... [Pg.80]

Flask F is provided with a two-hole cork stopper connected with tube E, and with tube G which connects with the first condenser II and may be of smaller bore than tubes C and E. H is. a. condenser with a 30-cm. water jacket. H is connected with I by means of an adapter. / is a i-l. round-bottom flask supported in a pan which is at first filled with ice and later used as a water bath. Flask I is fitted with a two-hole cork stopper carrying the adapter connected with condenser H and a Vigreux column K of 2-cm. diameter and a length of 30 cm. to the side arm. Flask I and condenser H are covered with black cloth (Note 2). The side arm of K is connected with a 90-cm. water-jacketed condenser L which leads into M through an adapter, iff is a 750-cc. Erlen-meyer flask immersed in an ice bath. Flask M is provided with a two-hole stopper connected with the adapter from L and an upright bulb condenser that is provided with a tube leading through a window or to a hood. [Pg.2]

A distilling flask ( litre) is fitted with a double-bored cork. Through one hole a thermometer is inserted, the bulb of which must be covered by the liquid in the flask and through the other a tap-funnel passes. The side-tube of the distilling flask is fixed by a coik into the upper end of a long condenser. An adapter is fitted to the lower end and passes through the neck of a flask, which is surrounded by ice. The apparatus is shown... [Pg.59]

The reaction mixture is now surrounded by an ice and salt mixture. The separatory funnel is replaced by a two-hole rubber stopper containing a thermometer (bulb immersed in the reaction mixture) and a glass tube the outer end of which is connected to a mercury trap (Note 3). When the temperature of the reaction mixture has fallen to 0°, the condenser is replaced by a tube 10 mm. in diameter and adjusted so the end is 50 nun. above the surface of the reaction mixture. The reaction mix-... [Pg.104]

Figure 1. Diagram of the venom duct of Conus. The venom is produced in the venom duct, apparently expelled from the duct into the proboscis by contraction of the venom bulb. Simultaneously, a harpoon-like tooth is transferred from the radula sac to the proboscis. When injection takes place, the venom is pushed through the hollow tooth and flows into the prey through a hole at the tip of the tooth. Typically, fish-hunting cones will strike at a fish only once and grasp the tooth after injection has occurred, effectively harpooning their prey while injecting the paralytic venom. In contrast, snail-hunting cones will usually sting their prey several times before total paralysis occurs. (Reprinted with permission from the Second Revised Edition of Ref. 8. Copyright 1988 Darwin Press, Inc.)... Figure 1. Diagram of the venom duct of Conus. The venom is produced in the venom duct, apparently expelled from the duct into the proboscis by contraction of the venom bulb. Simultaneously, a harpoon-like tooth is transferred from the radula sac to the proboscis. When injection takes place, the venom is pushed through the hollow tooth and flows into the prey through a hole at the tip of the tooth. Typically, fish-hunting cones will strike at a fish only once and grasp the tooth after injection has occurred, effectively harpooning their prey while injecting the paralytic venom. In contrast, snail-hunting cones will usually sting their prey several times before total paralysis occurs. (Reprinted with permission from the Second Revised Edition of Ref. 8. Copyright 1988 Darwin Press, Inc.)...
To blow a very small hole the method described for multiple perforations in bulbs is useful (p. 72). [Pg.35]

A bulb with a number of small holes in it is useful in bubbling a gas through a liquid. These holes are easily made a small bulb is blown a very small area of the bulb is heated strongly, and the glaSs is pulled out by touching it with the fine point of a glass rod, and then... [Pg.41]

An alternative method is to use a very small flame on the original bulb, and to blow a thin-walled bubble, as in Figure 27, 111. A number of these bubbles are blown, then they are all broken off and each hole is smoothed off. If a bubble is broken accidentally, the hole can be blocked with damp asbestos paper so that more bubbles can be blown. [Pg.41]

The only difference between this type of joint and a normal butt joint is in the preparation of the capillary tube first the end of this is sealed off and a small fairly thin-wall bulb btown equal in diameter to the hole in the wide tube. The end of this bulb is then blown out and the joint made by the normal method. The flame must be directed so that the capillary is not collapsed. If the capillary has a very fine bore some difficuhy will be found in blowing through it. This may be overcome by connecting it to a compressed air line while the smaU bulb is btown the end of the bulb can then be pulled out with a rod and cut off to give the prepared end. [Pg.134]

Sample viewing area. A circular opening cut in the front of the metal case such that you can see your samples in their capillary tubes (and the thermometer bulb) all bathed in the oil bath. You put the tubes into the oil bath through the holes in the capillary tube stage. [Pg.82]

In a round-bottomed flask (capacity 1 1.) sodium hydroxide (80 g.) is dissolved by heating in water (80 c.c.), pure phenol (25 g.) is added to the hot solution, and the mixture is cooled to 60°-65° by dipping the flask in cold water, without shaking, however, so that separation of crystalline sodium phenoxide is avoided. By means of a two-holed cork the flask is then fitted with an efficient reflux condenser and a thermometer, the bulb of which dips into the liquid. Chloroform (20 g.) is next poured in through the condenser, and the contents of the flask are gently shaken a transient fuchsine-red colour is developed in the liquid. After a period of about ten minutes, during which the temperature of the mixture is maintained... [Pg.235]

Symptoms Irregular holes eaten in roots, stems, bulbs, tubers, buds, flowers, fruit and leaves of a wide range of plants. Seedlings fail to come up or are eaten off. Most damage occurs at night Telltale slime trails may be seen. [Pg.338]

Daffodil bulbs require well-drained soil and a sunny planting location. They should be planted in holes that are 3-6 inches deep and there should be 2-4 inches between bulbs. The bulb should be placed in the hole, pointed side up, root side down. Once the bulb is planted, water the area thoroughly. [Pg.38]

The whole unit is accommodated in a fume cupboard fitted with a scrubber unit to remove the acidic fumes before emission to the atmosphere. The constructional materials of the fume cupboard should be able to withstand the heat radiated from the hotplate and heating blocks. A digestion tube containing a 350°C thermometer with the bulb embedded in a 2-cm layer of sand occupies one hole in each block. The hotplate can be connected to the power source via a time-switch, which can be set to come on approximately 1 hour before commencement of work this saves valuable time lost waiting for it to warm up. [Pg.33]

The copper bar (a) had a circular enlargement at. one end in which there were five holes the central one (F) contd mercury in which the bulb of a thermometer was immersed a small copper tube, contg 0.1 g of pulverized explosive to be tested, was placed in each of the other holes. The bar was supported on a stand and was heated by means of burners placed underneath it. The rate of heating could be regulated by moving the burners. The expl sample in tube (b) exploded first, then in (c) and (d) and finally (e). The... [Pg.169]

The tube of the bulb is inserted in a hole drilled in the stopper of the outer test tube. [Pg.294]

Heat one of the bulbs gently in the flame of a Bunsen burner and quickly place it in the hole in the lead plate so that the end of the capillary. is under the surface of the acid (Fig G17)... [Pg.721]

Step 1 Remove the electrode from its storage solution and rinse with purified water. Dab the electrode with tissue paper to remove excess water that could dilute the solution to be tested. Do not wipe the glass bulb. Place the electrode (and the temperature probe if applicable) into the first buffer to be tested. Wait for a stable response from the instrument. (Note If using a refillable electrode, open the fill-hole cover during calibration or any measurement to allow a uniform flow of electrode filling solution. Close the fill hole when the electrode is not in use.)... [Pg.237]

This main bulb was connected to a second bulb containing a modern ion gauge which measures or records gas pressures in a fraction of a second. It can measure pressures from about 10" ° to 10" mm. The system was connected to a liquid air trap and mercury diffusion pump through a movable glass plate with a small hole. The effective area of this hole was 0.010 cm. , and the pump speed was 0.12 liter/sec. This pump speed could be increased more than tenfold by removing the glass plate. [Pg.160]


See other pages where Bulbs, holes is mentioned: [Pg.153]    [Pg.766]    [Pg.303]    [Pg.88]    [Pg.8]    [Pg.21]    [Pg.32]    [Pg.39]    [Pg.1141]    [Pg.86]    [Pg.84]    [Pg.41]    [Pg.41]    [Pg.68]    [Pg.75]    [Pg.160]    [Pg.179]    [Pg.153]    [Pg.766]    [Pg.191]    [Pg.119]    [Pg.1]    [Pg.439]    [Pg.588]    [Pg.1050]    [Pg.303]    [Pg.24]    [Pg.35]    [Pg.208]   
See also in sourсe #XX -- [ Pg.72 ]




SEARCH



Bulbs

© 2024 chempedia.info