I-DPE

I.DPE (Low Density Polyethylene) Polyethylene plastic having a density typically between 0.910 and 0.925 g/cm. The ethylene molecules are linked in random fashion, with the main chains of the polymer having long and short side branches. The branches prevent the formation of a closely knit pattern, which results in a soft, flexible and tough... 

The reversible complexing of carbon dioxide by bis[bis(l,2-diphe-nylphosphino)ethane]iridium(I) chloride, [Ir(dpe)2]Cl, in acetonitrile [Eq. (36)] (48) appears not to involve carboxylation of a cyanomethylir-idium(III) complex or its formation by decarboxylation of the cyanoacetate... 

In the earlier ACW I Committee s report on the Eco Logic design, the most significant worker safety issue was expected to be maintenance of the COINS conveyor system by personnel in DPE suits (NRC, 1999). The conveyor system was to operate immersed in a hot caustic solution. The ACW II Committee s Demo II report noted the COINS process had been changed to provide for an overhead chain conveyor system to move the immersed baskets in the caustic bath (NRC, 2001b). The committee remains concerned that the COINS will require significant maintenance by personnel in DPE suits and finds that efforts to minimize maintenance should continue. 

The tests on DPE suit material and wood addressed size-reduction and material-transport problems identified during the Demo I testing (NRC, 2000a). DPE suit and butyl rubber simulant materials were shredded in a dedicated granulator, cryogenically cooled in a cryo-cooler with an internal screw conveyor, and reduced in a cryocooled hammer mill. No materials contaminated with agent were tested. 

Middleton P, Dickson DPE, Johnson CE, Rush JD. 1978. Interpretation of the Mossbauer spectra of the four-iron ferredoxin from Bacillus stearothermophilus. Eur I Biochem 88 135 1. 

After this the slurry is filtered, the filtrate evaporated to a sp gr 1.270 and is chilled to cause crystallization of impure PE. Then the slurry i s transferred to a "Nutsch" or to a centrifuge (wringer) to separate the crysts of impure PE from the mother liquor, which must be saved because it contains DPE and ocher PolyPE s such as TPE (tripentaerythritol) and TePE (tetrapentaerythritol)... 

P-Diketonesfrom %/i-epoxy ketones. 2 In the presence of this Pd(0) complex a,/ -epoxy ketones isomerize to /3-dikelones. An added ligand is usually necessary to avoid precipitation of palladium. The most satisfactory adjunct is l,2-bis(diphenyl-phosphino)ethane (dpe). The reaction is conducted in toluene at 80-140° for 10 100 hours. The isomerization is facile with strained epoxides it is sluggish with epoxides bearing an a-alkyl group. 

On account of their diamagnetism and spectral properties the [NiX2(dpe)2] complexes have a substantial square planar structure in the solid state, possibly with two weakly interacting anions in axial positions, as found in Nil2(diars)2 (vide infra). In solution either five-coordinate or square planar species are formed.1277 3283,1347 The ligand tep (II) easily forms diamagnetic five-coordinate complexes [NiX(tep)2]Y in the solid state and in solution as well.1276,1281,1282 The structure of [NiI(tep)2]I is essentially square pyramidal.1281... 

Gold(I) acetylide complexes have been prepared from alkynyllithium compounds [Eq. (22)] (63), and a dimeric complex [(PhC=C)Au(/u.-dpe)-Au(C=CPh)] [dpe = bis(diphenylphosphino)ethane] was obtained analogously. The simplest acetylide complexes are perhaps those containing only acetylide ligands. The compounds [Au(C=CPh)]x and [Au(C=C-/-Bu)]4 (1) contain cr- and 7r-bonded acetylide groups, the values of... 

Bi- and tetranuclear, three-center two-electron gold(I) complexes have been prepared containing polyfluorophenyl groups (129). The binuclear complexes are of the type discussed previously, [Ar(AuL)2]X and [Ar Au2(dpe) ]BF4, whereas the diarylaurates reacted to give tetranuclear compounds [Eq. (35)] suggested to be of the same type as the mixed metal complexes discussed above. 

A number of M(/i-H) M systems are known. These necessarily have both a bent M—H—M arrangement and, in view of the small covalent radius of H, a short M—M distance. Such systems also occur in metal clusters, e.g. the intensively studied Os3H2(CO)10. A strongly unsymmetrical bridge has been observed in [(dpe)Pt(/i-H)2PtH(dpe)]+ by neutron diffraction.8... 

Abbreviations arene, i/6-benzene or substituted benzene derivative bipy, 2,2 -bipyridyl Bu, Bu", Bu, iso-, n-, or rerf-butyl COD, 1,5-cyclo-octadiene Cp, /5-C5H5 DAD, dimethyl-acetylene dicarboxylate dam, 1,2-bis(diphenylarsino)methane DBA, dibenzylideneacetone DMF, A. A -dimethylformamide dpe, l,2-bis(diphenylphosphino)ethane dpen, os-l,2-bis(di-phenylphosphino)ethylene dpm, 1,2-bis(diphenylphosphino)methane ESR, electron spin resonance F6-acac, hexafluoroacetylacetone FN, fumaronitrile MA, maleic anhydride Me, methyl MLCT, metal ligand charge transfer phen, 1,10-phenanthroline Pr , Pr", iso- or n-propyl py, pyridine RT, room temperature TCNE, tetracyanoethylene tetraphos, (Ph2PCH2CH2)jP THF, tctrahydrofuran Xylyl, 2,6-Me2C6H3. 

To overcome the difficulty in the crossover step a general methodology has been developed in our laboratory for the synthesis of block copolymers when the second monomer is more reactive than the first one. It involves the intermediate capping reaction with non-(homo)polymerizable monomers such as i) 1,1-diphenylethylene (DPE) and its derivatives and ii) 2-substitut-ed furans. 

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