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Fluorine tests

Greater than 99% of the technetium and uranium was volatilized from the fluorinator in all fluorination tests. [Pg.527]

A test for fluorine in minerals is described on page 221 in connection with the zirconium-alizarin reaction. The fluorine test described on page 224, which depends on the etching of glass by hydrofluoric acid may also be applied to the rapid detection of fluorine in samples of rock or mineral waters. This test is especially recommended when there is much phosphate present, because then the alizarin test is not specific (see page 222). [Pg.554]

In view of the sensitivity of the fluorine test, it can be assumed that the latter four waters, if they contain any fluorine at all, carry much less than... [Pg.554]

Fluorine. Test by conversion into silicon tetrafluoride. [Pg.609]

Halogens can act as ligands and are commonly found in complex ions the ability of fluorine to form stable complex ions with elements in high oxidation states has already been discussed (p. 316). However, the chlorides of silver, lead(Il) and mercury(l) are worthy of note. These chlorides are insoluble in water and used as a test for the metal, but all dissolve in concentrated hydrochloric acid when the complex chlorides are produced, i.e. [AgCl2] , [PbC ] and [Hg Clj]", in the latter case the mercury(I) chloride having also disproportionated. [Pg.345]

Most fluorine-containing compounds can be reduced to the fluoride ion, F , which can be detected by the tests given below. [Pg.348]

Fluorine. Strongly acidify 2 ml. of the fusion solution with glacial acetic acid, and boil until the volume is redueed by about one half. Cool. Use either of the following tests. [Pg.1043]

Eluorspar assay may be completed by fluoride determination alone, because the mineralogical grouping rarely iacludes fluorine minerals other than fluorite. Calcium can be determined as oxalate or by ion-selective electrodes (67). SiUca can be determined ia the residue from solution ia perchloric acid—boric acid mixture by measuriag the loss ia weight on Aiming off with hydrofluoric acid. Another method for determining siUca ia fluorspar is the ASTM Standard Test Method E463-72. [Pg.175]

The high fluorine content contributes to resistance to attack by essentially all chemicals and oxidizing agents however, PCTFE does swell slightly ia halogenated compounds, ethers, esters, and selected aromatic solvents. Specific solvents should be tested. PCTFE has the lowest water-vapor transmission rate of any plastic (14,15), is impermeable to gases (see also Barrierpolymers), and does not carbonize or support combustion. [Pg.393]

J. B. Pallix, C. H. Becker, and K. T. Gillen, Appl. Surface Sck 32,1 (1988). An applications oriented discussion of using MPI-SALI for depth profiling, interface analysis in inorganic material systems. Examples of SALI depth profiles are given of a B implant in Si and the fluorine implanted electronic test device which was referenced in this encyclopedia article. [Pg.570]

Some authors have suggested the use of fluorene polymers for this kind of chromatography. Fluorinated polymers have attracted attention due to their unique adsorption properties. Polytetrafluoroethylene (PTFE) is antiadhesive, thus adsorption of hydrophobic as well as hydrophilic molecules is low. Such adsorbents possess extremely low adsorption activity and nonspecific sorption towards many compounds [109 111]. Fluorene polymers as sorbents were first suggested by Hjerten [112] in 1978 and were tested by desalting and concentration of tRN A [113]. Recently Williams et al. [114] presented a new fluorocarbon sorbent (Poly F Column, Du Pont, USA) for reversed-phase HPLC of peptides and proteins. The sorbent has 20 pm in diameter particles (pore size 30 nm, specific surface area 5 m2/g) and withstands pressure of eluent up to 135 bar. There is no limitation of pH range, however, low specific area and capacity (1.1 mg tRNA/g) and relatively low limits of working pressure do not allow the use of this sorbent for preparative chromatography. [Pg.167]

Direct oxide reduction (DOR) is presently being tested on production equipment. Eventually, it is hoped to eliminate the fluorination and bomb reduction processes and replace them with DOR. [Pg.349]

Self-Test 1.15B Account for the large decrease in electron affinity between fluorine and neon. [Pg.170]

Partially fluorinated X-IP has been used for a number of years as an additive in the inert lubricant PFPE film on the surface of a magnetic hard disk to enhance start/stop durability of PFPE lubricants [29,30]. Recently it has been used as a vapor lubricated film on the surface of the disks [31 ]. In order to avoid the PFPE being catalyzed to decomposition by the slider material AI2O3 (refer to Section 3.4), XI -P was also examined as a protective film on the surface of the magnetic heads [25,32]. The results of CSS tests indicate that the thermal stability of the lubricant was greatly improved in the presence of X-1P, and the thickness of X-1P film on the slider surface has an important influence on HDD lubrication properties. [Pg.214]

Compounds lb and 2b were the Urst fluorinated ligands tested in Mn-catalyzed alkene epoxidation [5,6]. The biphasic Uquid system perfluorooc-tane/dichloromethane led to excellent activity and enantioselectivity (90% ee) in the epoxidation of indene with oxygen and pivalaldehyde (Scheme 1, Table 1). In addition, the fluorous solution of the catalyst was reused once and showed the same activity and selectivity. This represents a considerable improvement over the behavior in the homogeneous phase, where the used catalyst was bleached and reuse was impossible. Unfortunately, indene was the only suitable substrate for this system, which failed to epoxidize other alkenes (such as styrene or 1,2-dihydronaphthalene) with high enantioselectivity. The system was also strongly dependent on the oxidant and only 71% ee was obtained in the epoxidation of indene with mCPBA at - 50 °C. [Pg.153]

With this in view, we studied the development of the dehydrofluorination reaction of CF3CH2CI as function of the degree of fluorination of chromium oxide. Moreover, nickel and chromium oxide catalysts were prepared and tested for the dehydrofluorination reaction. Nickel oxide, a basic compound [S], could poison selectively the tes involved during the dehydrofluorination reaction. [Pg.380]

Two Ni-Cr catalysts containing one 5 % nickd atomic and the other 10 % were tested for fluorination and dehydrofluorination reactions of CF3CH2CI. The results were compared to those obtained with chromium oxide alone. These reactions are performed only with the non fluorinated catalysts (table 2). [Pg.383]

In contrast, substituting the ort/to-methyl groups of SIMes with ortho-fluoride atoms profoundly alters the catalytic metathesis performance. In 2006, Grubbs and co-workers reported the synthesis of the fluorinated NHC-Ru catalysts 25 and 26 [41] (Fig. 3.8). Catalytic tests in the RCM of 1 to form 2 showed that the phosphine-free catalyst 26 was slower than the standard catalyst 16, which was consistent with theoretical investigations suggesting the electron-withdrawing fluoride atoms would lead to a decrease in catalyst activity [42]. However, in contrast to the computational... [Pg.69]

The discovery of the phenomenal insecticidal activity of 1,1, l-trichloro-2,2-bis(p-chlorophenyl)-ethane (DDT), which occurred less than 10 years ago, opened up a new field of endeavor for the chemist, biologist, and toxicologist. The activity in this field is considerable, and a portion of it has been directed toward efforts-to locate useful insecticides among the fluorine-containing compounds. Some of the fluorine compounds known to be insecticidal were re-evaluated, other compounds were tested biologically for the first time, and new compounds were prepared to be subjected to such tests. [Pg.160]

Difluorodiphenyl disulfide, when tested on woolen swatches, is an outstanding knockdown agent and toxicant for body lice. Several compounds with p-fluorinated phenyl radicals have exhibited the same order of activity against lice, but too few compounds with the disulfide linkage have been tested to warrant an appraisal of its effect here. [Pg.169]

Of a series of fluorinated benzenes and fluorinated toluenes tested with and without... [Pg.169]


See other pages where Fluorine tests is mentioned: [Pg.465]    [Pg.440]    [Pg.465]    [Pg.440]    [Pg.118]    [Pg.132]    [Pg.242]    [Pg.578]    [Pg.334]    [Pg.366]    [Pg.105]    [Pg.1952]    [Pg.374]    [Pg.954]    [Pg.25]    [Pg.1135]    [Pg.382]    [Pg.523]    [Pg.652]    [Pg.497]    [Pg.213]    [Pg.218]    [Pg.155]    [Pg.99]    [Pg.200]    [Pg.138]    [Pg.169]   
See also in sourсe #XX -- [ Pg.348 ]

See also in sourсe #XX -- [ Pg.348 ]

See also in sourсe #XX -- [ Pg.136 ]




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Fluorine test for, in compounds

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