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Life limitations

In contrast to the extreme reactivity of the monomeric PX (1) generated from it, the dimer DPX (3) feedstock for the parylene process is an exceptionally stable compound. Because of their chemical inertness, dimers in general do not exhibit shelf-life limitations. Although a variety of substituted dimers are known in the Hterature, at present only three are commercially available DPXN, DPXC, and DPXD, which give rise to Parylene N, Parylene C, and Parylene D, respectively. [Pg.430]

PVAc is another important type of adhesive, especially in furniture manufacturing and for carpentry. They form the bond line in a physical process by losing their water content to the two wooden adherends. PVAc adhesives are ready to use, have short setting time and give flexible and invisible joints. They are easy to clean and show long storage life. Limitations are their thermoplasticity and the creep behavior. [Pg.1077]

Limited power range Careful maintenance essential. Life limitations... [Pg.515]

After these comments it is understandable that this expensive and life-limited system could succeed only in a few special applications, where the high energy and power density could not be achieved by other systems. [Pg.287]

Phosphorus accounts for 2 1% of the dry weight of living cells. The phosphorus content of the environment can be the life-conserving or life-limiting factor (Karl, 2000). [Pg.115]

Radical are believed to be important in the aging process in the sense that radicals are involved in the development of the chronic diseases that are life limiting. [Pg.366]

Invent medicines that go beyond treatment to provide cure or prevention of life-limiting conditions and diseases such as cancer, Alzheimer s disease, mental illness, and diabetes. [Pg.95]

The total exclusion of air from vessels and equipment containing peroxide formers, and the establishment and observing of strict shelf life limitations, are basic strategies for managing peroxide-forming hazards. [Pg.28]

There are complications however. The cathodic potential effectively stops corrosion on the metal substrate but it also contributes to early debonding of adherends, the development of leak paths under seals, and the blistering and peeling of coatings. Degradation of protective coatings is a basic life-limiting problem for underwater equipment exposed to a cathodic potential. [Pg.169]

Delamination represents the weakest failure mode in laminated eomposites, and is considered to be the most prevalent life-limiting crack growth mode in most composite structures. As such, ever-increasing attention has been directed toward the understanding and characterization of delaminations of various natures, and at... [Pg.74]

The disadvantages of pad A, as compared to pad B, are twofold (1) the grooving imposing a pad-life limit, because once the grooves are worn out, the pad can no longer polish and (2) the difficulty in putting the whole pad successfully on a platen without entrapping bubbles to accomplish this, more skilled technicians are required. Perforated pads do not have these problems. [Pg.249]

Stack material and architecture combinations that allow for effective sealing and reduction in life-limiting thermal stresses during thermal cycles. [Pg.189]

Loucas et al. studied the stability of procaine hydrochloride in a buffered cardioplegic solution [154]. The time required for procaine to degrade to the lower shelf-life limit of 90% of its initial concentration was extrapolated to be approximately two days at room temperature, and eleven days under refrigeration. [Pg.447]

MeV a) in hopes that the time base of the experiments could be reduced. However, this isotope is available only twice a year and its short half-life limited the experiments to a short period of time. [Pg.291]

The system has a number of attractive features, especially the flexibility of capacity and power output capacity can be increased simply by enlarging the size (or number) of the storage tanks power output can be raised by increasing the flow rate or by bringing into line parallel cell sections (cf. fuel cells). Further advantages include low operating temperatures and the absence of discharge depth or cycle life limitations. [Pg.301]

The coarse grains developed by conventional casting processes usually arc deleterious to fatigue life. For parls such as turbine disks that arc life-limited by latiguc rather than creep, fine grains are produced by powder metallurgical techniques. [Pg.776]

CuDAL Approach. The CuDAL approach is specifically written for tablets or capsules. This approach is recommended in the PDA paper [1] for final product testing. For content uniformity, when the potency limits are not symmetrical about 100% of label claim, the USP 25 content uniformity test allows the individual results to be expressed as either a percentage of the label claim, the found mean, or the average of the upper and lower potency specifications, depending on the value of the sample mean. Acceptance limits have not been constructed for the more complicated situation in which the potency shelf life limits are not symmetric about 100%. One approach to this problem is to evaluate the content uniformity results twice. First express the sample mean as a percentage of label claim and then express the mean as a percentage of the average of the potency specifications. To pass the acceptance limits, both means must meet the acceptance criteria. To use the dissolution acceptance limit tables, the value of Q is required. [Pg.717]

Simulation. One approach is to assume the sample mean and standard deviation are the true population mean and standard deviation, to provide a best estimate of the true probability of passing. This has the advantage that it can provide estimates of the probability of passing at any stage and can handle the nonsymmetric potency shelf life limits in the content uniformity test. The disadvantage is that it does not provide a bound on the probability with high assurance and is not a function of sample size. It can provide a good summary statistic of the content uniformity data, however. [Pg.717]

As a technique for measuring nuclear moments and investigating nuclear level structure, low temperature nuclear orientation has long been kept from areas of current activity in low energy nuclear physics by the half life limitation caused by needs of sample preparation and cooling to below 1 K. [Pg.349]

The current mantra of astrobiology is follow the water. Where there is water, there may be life. The FREZCHEM model can determine the presence or absence of water down to the eutectic temperature, below which only solid phases are thermodynamically stable. Salinity, the desiccation potential, and acidity are other potentially life-limiting factors that are calculated by FREZCHEM. In Chap. 4, we discuss potential life-limiting factors such as temperature, salinity, acidity, desiccation, radiation, pressure, and time. [Pg.2]

Hunting Common and a way of life Limited to specific communities in some remote parts of the region Limited to some communities in the remoter parts of the region Limited to some communities in the remoter parts of the region... [Pg.15]

Ni-state-of-the-art anodes contain Cr to eliminate the problem of sintering. However, Ni-Cr anodes are susceptible to creep, while Cr can be lithiated by the electrolyte and consumes carbonate, leading to efforts to decrease Cr. State-of-the-art cathodes are made of lithiated-NiO. Dissolution of the cathode is probably the primary life-limiting constraint of MCFCs, particularly under pressurised operation. The present bipolar plate consists of the separator, the current collectors, and the seal. The bipolar plates are usually fabricated from thin sheets of a stainless steel alloy coated on one side by a Ni layer, which is stable in the reducing environment of the anode. On the cathode side, contact electrical resistance increases as an oxide layer builds up (US DOE, 2002 Larminie et al., 2003 Yuh et al., 2002). [Pg.62]

Liquid-phase chemical separation techniques have been used for over 100 years, thus their utility for separation and isolation of the chemical elements has been demonstrated. Adaptations of these well-understood separation techniques have been applied to the transactinide elements. These adaptations have been developed to overcome the single-atom and short half-life limitations inherent in the study of transactinide element chemical properties. [Pg.128]


See other pages where Life limitations is mentioned: [Pg.122]    [Pg.428]    [Pg.368]    [Pg.48]    [Pg.422]    [Pg.814]    [Pg.1008]    [Pg.267]    [Pg.176]    [Pg.323]    [Pg.18]    [Pg.139]    [Pg.373]    [Pg.308]    [Pg.329]    [Pg.345]    [Pg.129]    [Pg.674]    [Pg.969]    [Pg.618]    [Pg.8]    [Pg.2]    [Pg.4]    [Pg.7]    [Pg.34]    [Pg.96]   
See also in sourсe #XX -- [ Pg.312 ]




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Life cycle analyses limitations

Limited life items

Limits for Life

Membrane Life-Time Limitation

Part Durability and Life Limitation

Shelf life limiting attribute

Shelf-life limits

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