Poor Quality Materials

Poor Quality Materials. One laboratory built an extension to an existing work bench. The idea was both logical and practical. But why did they use the cheapest grade lumber available, full of 

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Hydrogenated amorphous silicon is not a homogeneous material. Its structure is thought to consist of voids embedded in an amorphous matrix [62, 63]. The size and number density of the voids depend on the deposition conditions. Poor-quality material can have a void fraction around 20%, while device quality a-Si H has been shown to contain fewer voids, 1%. with a diameter of 10 A [64-66]. The surfaces of the voids may be partly covered with hydrogen atoms [62, 67],... 

The ratio of cellulose to acid used in practice ranges from 1 40 to 1 60, and in exceptional cases may be 1 80. A larger excess of acid is also recommended for nitrating poor quality material, which is much more difficult to wet with mixed acid. 

The introduction of standardized data formats, communication tools and formats will lead to a more immediate availability of data. Again, if the data are transformed into knowledge to allow for control of a process, their availability greatly reduces manufacturing costs, and reduces risks of poor-quality material production. Data need to be available in a useful format in a relevant time - a time which enables action to be taken. 

The good-quality amber was used for decorative purposes while the o T-cuts and poor-quality material was boiled down in oil, thinned and used as a hard varnish for wood, especially for musical string instruments or for ps. 

It was commonly thought by those in authority that if mithridatum or theriac did not produce the desired cure, this was due to incorrect preparation (perhaps with adulterated or poor-quality materials) or to incorrect storage after use. As the only cause for therapeutic failure therefore lay with the pharmacist who compounded the mixture, the remedy lay in careful scrutiny of manufacture, which should be in public. Any misdemeanor should then be detected and immediately punished. 

Quality assurance is of vital importance during the installation of a cover system whatever its design and whatever the type of materials used in construction. It is essential that the desired properties of individual component layers are maintained over the entire area and depth. Integrity must not be compromised by inappropriate or poor quality materials. Careless or inappropriate use of heavy construction equipment can damage previously completed layers, particularly when synthetics are used. The major advantages and disadvantages or a cover system are identified in Table 4. 

Earlier work revealed that refluxing (III) and (IV) at high temperature produced poor quality material in low yield. Additional work using glacial acetic acid and mercuric acetate in place of the nucleophillic amine was successful. However, this route makes isolation of the product difficult. The most promising route uses non-nucleophillic amines as a catalyst such as triethylamine in an aromatic hydrocarbon solvent. ... 

Manufacturing defects occur in a few products of the same make. Most manufacturing defects involve poor quality materials or shoddy workmanship. Some involve production irregularities and errors. 

Equation (3.21) will be used to evaluate the size effect on fatigue limit Sf passing from a standard cylindrical specimen of 6 mm diameter to a larger one having a diameter of 20 mm. Assume that the l/d ratio remains constant and equal to 3 (fatigue specimens have l/d > 3) and m — 25 (poor quality material), Eq. (3.21) yields... 

Alternatively, (part of) the poor quality materials may have to be removed prior to filling. 

Management of poor quality materials 6.7.1 Use of cohesive or fine grained materials... 

On the calender, the plastics passes for the first time through a fine friction nip and the gelling of the material is completed. The material must be kept continually on the move in the banks formed at the nips of the calender, cooling-off cannot be tolerated as poor quality material will be produced. The second and final nip should ideally have a small rolling bank of material present which should be just big enough to prevent nip starvation and therefore avoid holes in the sheet. With individual d.c. motors and geared drives to each roll, friction ratio between rolls can be set and this will cause the nip banks to roll and improve quality. 

Employ QC to ensure that no problems are caused by errors, or by poor quality materials goods services workmanship, etc. Pollow the Step 5 verification plans to verify the EM and physical performance of the EFS - and any measures not Incorporated within it. 

Disasters Emergency Committee (UK)] Member Agencies ultimately did adopt seismic design approaches but this was not always matched by quality construction and the design intent was compromised by poor quality materials and workmanship on site. In some cases remedial works and retro-fitting was needed to create a safe structure. ... 

UNSCOM verified that the principal CW agents produced by Iraq were sulfur mustard and the organophosphorus nerve agents cyclosarin, sarin, and tabun. The main CW issue that lacked resolution was the nature and extent of Iraq s program to produce VX. The Iraqi government claimed to UNSCOM that it had never filled weapons with VX but had merely produced limited, pilot plant-scale quantities of the nerve agent, totaling two to three tons of poor-quality material. UNSCOM disputed this claim. In late 1998, UNSCOM was forced to... 

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