PIP method

The PIP method includes the slurry infiltration of fiber preforms by means of resin transfer molding (RTM) with suitable precursors such as polycarbosUane (PCS) or pol-yvinylsilane (PVS) followed by subsequent crosslinking to thermosets (resulting in fiber-reinforced polymers). The polymer composite is then pyrolyzed at temperatures below 1400°C in inert atmospheres to yield a CMC (Fig. 12.9(c)). 

HPDLCs are fabricated by photo-polymerization induced phase separation (PIPS) method by exposing a mixture of LC(s) and photo-sensitive monomer(s) to a laser optical interference field [38 1]. The laser optical field is created by two or multiple coherent laser beams. The periodic structure in HPDLCs is composed of alternating lamellas of polymer-rich layer and phase-separated LC-rich layer, in... 

K. Yoshida, M. Imai and T. Yano, Room- and Elevated-Temperature Mechanical Properties of SiC Fiber-Reinforced SiC Composite Fabricated by CVI and PIP Methods, J. Ceram. Soc. Japan, 108, 224-229 (2000). 

The advancement of PIP method of the porous C/C composites with an initial bulk density of 0.68g/cm and open porosity of 60% was examined by density measurements. The bulk density of the C/C-ZrB -ZrC-SiC composites produced according to the number of PIP cycles is shown in Figure 7, which corresponds volume ratios of the formed ZrB 2 ZrC SiC matrix of 20 30 50 (Table 3). It shows a gradual decrease in the impregnation efficiency with increasing of the number of PIP cycles. After 16 PIP cycles, the bulk density increases by less than 2%. 

However, CVD, CVI and PIP methods have disadvantages for the practical use of continuous SiC/SiC composites. These processes require very long time to achieve the SiC/SiC composites because of low ceramic yield and slow deposition rate. Figure 2 shows SEM micrographs of the microstructure of the SiC/SiC composites fabricated by CVI and PIP methods. The SiC/SiC composites fabricated by CVI or PIP process usually contain large amount of voids, pores and cracks and their... 

Figure 2. SEM micrographs of the microstructure of the SiC /SiC composites fabricated by (a) CVI and (b) PIP methods...

Yoshida, K., Imai, M., Yano, T. (2000). Room- and elevated-temperature mechanical properties of SiC fiber-reinforced SiC composite fabricated by CVI and PIP methods. Journal of the Ceramic Society of Japan, 108,224—229. doi 10.2109/ jcersj.l08.1255 224. 

The pull-in-place (PIP) method is the second CIPP installation technique. Here the liner is pulled into the old pipe through an existing access or manhole structure and cured in place. In some applications, the PIP technique includes using a slip sheet... 

In spite of the frequency-shifted excitation, the quantized PIP inevitably excites multiple sidebands located at n/At ( = 1, 2,...) from the centre band. An attempt was made16 to calculate the excitation profile of multiple bands created by a PIP of a constant RF field strength, using an approximate method based on the Fourier analysis. The accuracy of the method relies partly on the linear response of the spin system, which is, unfortunately, not true in most cases except for a small angle excitation. In addition, the spins inside a magnet consitute a quantum system, which is sensitive not only to the strengths but also to the phases of the RF fields. Any classical description is doomed to failure if the quantum nature of the spin system emerges. 

A more modern method to check for loss of thickness in process piping is by ultrasonic testing (UT) or Sonaray. These are portable instruments used to check pipe thickness on-stream. Do not forget, though, that the thin elbow, the one that is sure to fail, is always out of reach unless a ladder can be found. And the inspector cannot find the ladder. The outside radius of elbows are typically the thinnest portions of a pip-... 

In solution-phase peptide synthesis, acylation of amino acids or peptides with N-protected azetidine-2-carboxylic acid is performed via the active esters, e.g. A-hydroxysuccin-imide 100 111-112 or pentachlorophenyl ester, m 117 as well as by the mixed anhydride 101114 or carbodiimide 118 methods. An attempt to prepare the A-carbonic acid anhydride by cycli-zation of A-(chloroformyl)azetidine-2-carboxylic acid with silver oxide in acetone or by addition of triethylamine in situ failed, presumably due to steric hindrance. 111 In SPPS, activation of the Fmoc-protected imino acid by HBTU 119,120 is reported. In solution-phase peptide synthesis, coupling of N-protected amino acids or peptides to C-protected azetidine-2-carboxylic acid or related peptides may be performed by active esters, 100 118 121 mixed anhydrides, 95 or similar methods. It may be worth mentioning that the probability of pip-erazine-2,5-dione formation from azetidine-2-carboxylic acid dipeptides is significantly reduced compared to proline dipeptides. 111 ... 

Egorov, O. B., Addleman, R. S., O Hara, M. J., Marks, T., and Grate, J. W., Direct measurement of alpha emitters in liquids using passivated ion implanted planar silicon (PIPS) diode detectors, Nucl. Instrum. Methods Phys. Res., Sect. A, 537, 600-609, 2005. 

The compound different methods (148) tlie compounds show no tendency to isomerize in solution (155). The compound Rh(C0)(PPhg)2NCSe... 

This is perfectly understandable and many patients use unproven methods, including medicines (see complementary medicine). Innumerable methods are and have been offered for cancer. A prominent remedy was laetrile, a preparation of apricot seeds (pits, pips), which contains amygdalin (a p-glucoside) which incorporates cyanide. It was claimed to relieve pain, prolong survival and even to induce complete remission of cancer. Benefit was reputed to result from release of cyanide in the body which... 

The ICP-SFMS instrument was tuned using a I ng mf uranium standard solution prior to analysis. Sensitivity was about 2 x 10 cps for 1 ng g" solution. Concentrations of plutonium isotopes and " Am were calculated as a function of Pu/ Pu, Pu/ Pu, Pu/ Pu and Am/ Am ratios according to the isotope dilution method. All raw data were corrected for instrumental mass bias using linear correction. NdFs micro coprecipitated alpha sources were counted by a PIPS type alpha Si detector with a surface... 

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