Probable cause

M.p. 103°C. Noradrenaline is released in the adrenal medulla with adrenaline, and also at the sympathetic nerve endings. Its release from a nerve fibre is followed by binding to a receptor molecule on the next nerve or muscle fibre, probably causing a change in the electrical charge of the receptor-cell membrane. Biosynthetically it normally serves as a precursor for adrenaline. 

Right about now the chemist is probably screaming, "Hey, where the hell is my big yield of you-know-what ". Sorry. Charlie. This way of aminating is easy but chemically it s a crap shoot with yields anywhere from 10-50%. The theoretical odds are against the reaction but if it is done as outlined here, the chances of success are better. Actually, Strike thinks the yields could be higher because half the problem was probably caused by low bromosa-frole yield which we have hopefully corrected in the preceding section ... 

More recent developments are based on the finding, that the d-orbitals of silicon, sulfur, phosphorus and certain transition metals may also stabilize a negative charge on a carbon atom. This is probably caused by a partial transfer of electron density from the carbanion into empty low-energy d-orbitals of the hetero atom ( backbonding ) or by the formation of ylides , in which a positively charged onium centre is adjacent to the carbanion and stabilization occurs by ylene formation. 

Spike recoveries for samples are used to detect systematic errors due to the sample matrix or the stability of the sample after its collection. Ideally, samples should be spiked in the field at a concentration between 1 and 10 times the expected concentration of the analyte or 5 to 50 times the method s detection limit, whichever is larger. If the recovery for a field spike is unacceptable, then a sample is spiked in the laboratory and analyzed immediately. If the recovery for the laboratory spike is acceptable, then the poor recovery for the field spike may be due to the sample s deterioration during storage. When the recovery for the laboratory spike also is unacceptable, the most probable cause is a matrix-dependent relationship between the analytical signal and the concentration of the analyte. In this case the samples should be analyzed by the method of standard additions. Typical limits for acceptable spike recoveries for the analysis of waters and wastewaters are shown in Table 15.1. ... 

Cullinan presented an extension of Cussler s cluster diffusion the-oiy. His method accurately accounts for composition and temperature dependence of diffusivity. It is novel in that it contains no adjustable constants, and it relates transport properties and solution thermodynamics. This equation has been tested for six very different mixtures by Rollins and Knaebel, and it was found to agree remarkably well with data for most conditions, considering the absence of adjustable parameters. In the dilute region (of either A or B), there are systematic errors probably caused by the breakdown of certain implicit assumptions (that nevertheless appear to be generally vahd at higher concentrations). 

By tire coiTect choice of the metal oxide/carbon ratio in the ingoing burden for the furnace, the alloy which is produced can have a controlled content of carbon, which does not lead to the separation of solid carbides during the reduction reaction. The combination of the carbon electrode, tire gaseous oxides and the foamed slag probably causes tire formation of a plasma region between the electrode aird the slag, and this is responsible for the reduction of elecU ical and audible noise which is found in this operation, in comparison with tire arc melting of scrap iron which is extremely noisy, and which injects unwanted electrical noise into the local electrical distribution network. 

So in this chapter of failure analysis and corrective methods, we decided to consider some problems, symptoms, and remedies particular to PD pumps. We re using two tables. The first table lists the few symptoms that send a PD pump into the shop. These symptoms are mated to another column of possible causes listed in numerical order. The numerical causes are on the second tabic starting with the. source of the problem in the left column and the probable cause/suggested remedy in the right column. As you go through the list, you ll see again that PD pumps and centrifugal pumps have a lot in common. Enjoy. 

The probable causes were compared to the data available and the physical conditions of equipment w ere checked. Probable causes were identified. 

TROUBLE PROBABLE CAUSE(S) TROUBLE PROBABLE CAUSE(S)... 

TROUBLE EXCESSIVE CARBON ON VALVES PROBABLE CAUSE(S) 1. Excessive lube oil. 2. Improper lube oil (too light, high carbon residue). 3. Oil carryover from inlet system or previous stage. 4. Broken or leaking valves causing high temperature. 5. Excessive temperature due to high pressure ratio across cylinders. 

TROUBLE PROBABLE CAUSE(S) 4. High inlet temperature. 5. Fouled water jackets on cylinder. 6. Improper lube oil and/or lube rate. 

The use of fire retardants in polymers has become more complicated with the realisation that more deaths are probably caused by smoke and toxic combustion products than by fire itself. The suppression of a fire by the use of fire retardants may well result in smouldering and the production of smoke, rather than complete combustion with little smoke evolution. Furthermore, whilst complete combustion of organic materials leads to the formation of simple molecules such as CO2, H2O, N2, SO2 and hydrogen halides, incomplete combustion leads to the production of more complex and noxious materials as well as the simple structured but highly poisonous hydrogen cyanide and carbon monoxide. 

Fumed silicas have an amorphous nature probably caused by the fast cooling during the manufacturing process. It is an important benefit because it does not cause silicosis. 

Each of these is probably caused by deficiencies in management, its planning, organization, or control. 

The results were not serious. The pumps supplied water to cool the hot gases leaving an incinerator when the water flow stopped, a high-temperature trip shut down the burner. The incinerator was nev/, was still undergoing tests, and the job had not been done before. The water was recycled, and ash in it probably caused the choke [40]. 

The probable cause of the accident was overfilling due to level indicator failure. Water removal from carbon dioxide was not always sufficient to assure good pressure and level readings in the tanks. Residual water could cause meters to fail from ice formation. 

PVP K-120 peaks are distorted at the high molecular weight end for tht TSK-PW column in water and in water/methanol. The distortion is more severe in water than in water/methanol. If the distortion is caused by poor separation of the TSK GM-PW column, then the distortion should be more severe in water/methanol than in water, as it was shown earlier that the resolution should be better in water than in water/methanol. The distortion is probably caused by interaction between PVP K-120 and the TSK GM-PW column. There is a high molecular weight shoulder in the PVP K-90 peak for the TSK GM-PW column, especially in water. This may be the reason why M for PVP K 90 determined with the TSK GM-PW column are higher than from the other columns, as shown in Tables 17.3-17.6. 

Wluit is a core meltdownl What was the probable cause of the Three Mile Island incident ... 

In general, tlie carriage of hazardous materials does not appear to be a significant cause of, or aggravating factor in, aircraft accidents. However, improperly packed and loaded nitric acid was declared tlie probable cause of a cargo jet crash at Boston in 1973, in which tliree crewmen died,"... 

It appears, therefore, that quatemization of the unsubstituted quinazoline nucleus is the exception and that steric factors probably cause the substituted derivatives to react at the 1-position. 8-Hydroxy-quinazoline is believed also to quatemize at the 3-position here the effect of the hydroxyl group would be to reduce any tendency towards reaction at the 1-position and it is interesting that a monoalcoholate is isolated in this case too. ... 

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