Injection points

This relation is calculated assuming that no more than 5% of solute reaches the column walls, and also assuming a point injection of solute (ie the volume of injected solute is negligible) at the centre of column. 

Nonpharmacologic therapies include reassurance and counseling, stress management, relaxation training, and biofeedback. Physical therapeutic options (e.g., heat or cold packs, ultrasound, electrical nerve stimulation, massage, acupuncture, trigger point injections, occipital nerve blocks) have performed inconsistently. 

Fig. 10.3 Photographs of a homogenous, saturated sand pack with seven dye tracer point injections being transported, under a constant flow of 53 mL/min, from left to right times at (a) t=20, (b) t= 105, (c) t= 172, (d) t=255 min after injection. Internal dimensions of the flow cell are 86 cm (length), 45cm (height), and 10cm (width). Reprinted from Levy M, Berkowitz B (2003) Measurement and analysis of non-Fickian dispersion in heterogeneous porous media. J Contam Hydrol 64 203-226. Copyright 2003 with permission of Elsevier...

Rule-of-thumb estimates of the fill time are available for a few simple cases. One example that is useful in practice is the result for a square plate with side L. The expressions for the constant C for point injection, edge injection, and peripheral injection has been summarized in Table 12.2. These three elementary cases can often be used to get a relatively good estimate of the fill time even in cases with complicated geometry. 

In the preceding example and point injection the flow front will develop as a circular front, starting at the inlet, until it meets the closest side. From then on the front will tend to move unidirectionally in both directions toward the far sides (if there is no leakage at the sides). A reasonable estimate of the fill time is somewhere between the time to fill radially and the time to fill unidirectionally to the far side (flow distance 1.5 m). For the radial flow case L in Equation. 12.10 is 3 m (the diameter of a circle touching the wall farthest away). With the assumed alternative with unidirectional flow from the center toward both shorter sides, L in Equation. 12.10 is 1.5 m. It is also necessary to estimate an effective inlet radius, in this case an inlet radius of 5 mm is chosen yielding e = 3.3 10-3 that was used in the formula in Table 12.2. The constant C in Equation 12.10 is 0.5 for the unidirectional flow case and 0.65 for the radial flow case. The upper and lower limit for the fill time in this case are then ... 

Injection at strike point Injection at mid point of base target... 

Parris WCV, Dettbarn WD. Muscle atrophy following bupivacaine trigger point injection. Anesthesiol Rev 1989 16 50-4. 

If experiments show a possibility of mixing-sensitive reactions and the rate of addition is important, consider multiple point injections. The feed time will have to be increased in large-scale equipment. 

Oxidant introduction Complex multiple injection Simple single point injection... 

In previous discussion, the advantages of short gel times in flowing groundwater were related to single-point injections. The conclusions reached should apply equally well to stratified deposits through which a grout pipe is retracted in stages. 

A 70 mm solid tubing was used for the bottom (point) injection of the Siroc-Cement grout. Before each injection, the tubing was raised about 14 inches so as to yield a grout injection interval similar to that obtained by the 60 mm valved tubing. 

Column head. If one feeds a column with a diameter larger than 10 mm, a good distribution of the sample over the cross-section is essential. Using point--injection, the column will be centrally overloaded by infinite-diameter and often noticeable tailing is observed. If one wishes to obtain a high loading, one has to spread the sample homogeneously over the whole cross-section, as demonstrated in Fig. 2. 

Huang and Mujumdar (2007) were the first to investigate a spray dryer fitted with a centrifugal atomizer using a CFD model. In their model, they model the rotary disk atomization into the disk side point injection which is the same as the holes in the disk. 

Q. Are trigger point injections medical treatment since they can be either diagnostic or treatment . 

With multi-point injection of asymmetrical products, more balanced cavity filling may sometimes be achieved by appropriate positioning of the product in a mould (see Figure 6.3). After inversion of the product (b), a balancing of the flow paths in the HR system is achieved. 

Figure 6.11 Single-cavity mould for PC loudspeaker casing with 15-point injection in...

After selecting the gating system, which depends on the elastomer used (process-ability, cost), and the product (function, geometry, number, etc.), the injection is defined. Types of injection include direct injection, pin-point injection, or a film gate at the manifold layer (in some cases). The choice depends on the infrastructure, such as the construction of the molding machine. 

A steel mold (609.6 x 914.4 mm) with point injection and point vent was used to fabricate 508.0- by 609.6-mm plates. After the materials were placed, the mold was sealed using a vacuum bag and sealant tape. The mold was then infused under vacuum with a pressure of 1 atm. The resin-infused panel was cured in a convection oven at 60 °C for 2 h and postcured at 94 °C for 4 h. The manufactured composite plate consisted of eight plain fabric plies (thickness 4.75 mm) with a symmetric stacking sequence of (45/-45/0/90) s, an areal density of 250 g/m, and a resin mass content of 36.5% (Figure 19.1). 

Injection Method Wall injectors and, if required for distribution, lances. Typically few injection points. Wall injectors and, if required for distribution, lances. Typically many injection points. Injection lances/grids. 

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