Needle Penetration

The standard NF T 65-001 gives a classification for bitumen as a function of their hardness. This is measured using a needle penetrability test, which measures the penetration depth of a weighted needle into the bitumen. Five grades have been defined. 

The principal characteristics of bitumen are its softening point and its needle penetrability. In France the latter has always been the basis for bitumen classification and class designation. Yet, the former is more representative of a bitumen s capacity to deform when the service temperature increases. The other properties have more or less importance depending on the application. 

Penetrability is the depth, expressed in tenths of a millimeter, a standard steel needle penetrates into a bitumen sample at 25°C. The needle carries a weight of 100 g and the test is applied for five seconds. The corresponding test method is relatively difficult to carry out and is defined in France by the standard NF T 66-004, and in the USA by the method ASTM D 583. Penetration is related to the viscosity. 

Needle penetration (bitumen) NF EN 1426 ISO/DIS 3997 ASTM D5 Penetration of weighted needle... 

Penetration (ASTMD5). This is a commonly used consistency test. It involves the deterrnination of the extent to which a standard needle penetrates a propedy prepared sample of asphalt under definitely specified conditions of temperature, load, and time. The distance that the needle penetrates in units of mm/10 measured from 0 to 300, is the penetration value. Soft asphalts have high penetration values. 

Needle penetration and resealability measures the force required to penetrate the target area of an elastomeric closure with a hypodermic needle and the ability of the closure to reseal when the needle is withdrawn. 

Septum. The syringe needle penetrates through the septum to introduce the sample. Septa are typically polymeric materials... 

Retrobulbar hemorrhages During the administration of botulinum toxin type A for the treatment of strabismus, retrobulbar hemorrhages sufficient to compromise retinal circulation have occurred from needle penetrations into the orbit. It is recommended that appropriate instruments to decompress the orbit be accessible. Ocular (globe) penetrations by needles have also occurred. An ophthalmoscope to diagnose this condition should be available. Inducing paralysis in 1 or more extraocular P.788... 

Fig. 7.13 Proctor needle penetration resistance for mortar sieved from concretes containing varying retarder levels.

In the Vicat test, the polymer sample is subjected to a load of 1 kg on a standard needle. The sample is immersed in a bath and heated, and the softening point is defined as the temperature at which the loaded needle penetrates to a depth of 1.0 mm. 

Vectors can be injected into the kidney at the location of choice or at multiple sites either beneath the capsule or into the renal parenchyma. The disadvantage of this technique is that the transgene expression is limited to renal tissue surrounding the needle track and the needle penetration per se can cause cell damage. This approach could be relevant for localized renal tumors where anti-angiogenic, pro-apoptotic, or tumor-suppressive genes could be injected. 

Melt index is close to 3.5, tensile strength about 1,500 psi (6.9 MPa), melting point of 99 to 100C, and needle penetration test at 25C is 1 to 10. Just over 10wt% of LDPE produced in the USA find use in typical wax applications, such as paper coatings and floor polishes. A major use is coated paperboard for milk cartons. 

Figure 9.47 Dispersion of Ventodisk or Becodisk contents by breath actuation a cross-section of a Diskhaler is shown with a disc located on the support wheel, (a) A disc is located beneath an aperture in the body of the Diskhaler through which a piercing needle enters, (b) The needle penetrates the upper and lower surfaces of the blister, (c) The patient inhales through the device and pierced blister, entraining the blister contents into the airstream.

Covers the determination of the temperature at which a specified needle penetration occurs when specimens are subjected to specified test conditions. The method is useful for many thermoplastic materials. The specimen and needle are heated at either of two permissable rates. The temperature at which the needle has penetrated to a depth of 1 mm is the Vicat softening temperature. 

Needle penetration Hoppler consistometer, Needle track tester A—>C 34... 

The measurement of the needle penetration of petroleum wax (ASTM D1321, IP 376) gives an indication of the hardness or consistency of wax. This method uses a penetrometer applying a load of 100 g for 5 s to a standard needle with a truncated cone tip. The sample is heated to 17°C (30°F) above its congealing point, poured into a small brass cylinder, cooled, and placed in a water bath at the test temperature for 1 h. The sample is then positioned under the penetrometer needle, which when released penetrates into the sample. The depth of penetration in tenths of millimeters is reported as the test value. This method is not applicable to oUy materials or petrolatum, which have penetrations greater than 250. 

The method for the determination of the cone penetration of petrolatum (ASTM D937, IP 179) is used for soft wax and petrolatum. It is similar to the method for determining the needle penetration (ASTM D-1321) except that a much larger sample mould is used and a cone replaces the needle. The method requires that a 150-g load be applied for 5 s at the desired temperature. 

Penetration ASTM D-5 The extent to which a needle penetrates... 

Corticosteroids have been used to treat a variety of ocular diseases. Traditionally, delivery of corticosteroids for posterior-segment eye diseases has been achieved through oral systemic therapy and periocular injections. Oral corticosteroids have not been widely used to treat DME, but when used for posterior inflammatory uveitis, they require high concentrations to reach therapeutic levels in the posterior segment. These high doses often result in systemic side effects (24). Periocular corticosteroid administration often must be repeated and may be associated with complications such as ptosis and inadvertent needle penetration of the globe. 

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