3,461 research outputs found
Investigating the rheological properties and compatibility behaviours of RET/PE and WR/CR/ SBS compound-modified bitumen
No full textTwo types of elastomer/plastic compound-modified bitumen were developed by means of incorporating the reactive elastomeric terpolymer (RET) into the plastic (high-density polyethylene HDPE or recycled polyethylene RPE) modified bitumen and adding the wax residue (WR) into the bitumen/elastomer (crumb rubber CR or styrene–butadiene–styrene SBS) blends. The rheological properties, morphology microstructure and storage stability of these novel elastomer/plastic compound-modified binders were characterised. The results revealed that RET elastomer positively improved the high-temperature modulus, temperature insensitivity, rut resistant, elastic recovery and shear-resistance of HDPE- and RPE-modified bitumen. However, excessive RET dosage adversely influenced the cracking resistance of plastic-modified bitumen, and its optimum dosage was recommended as 1 wt%. Moreover, RET elastomer significantly strengthened the storage stability of HDPE and RPE-modified binders. The elasticity improvement effect of RET was attributed to the generated polymer network. On the other hand, adding WR limitedly deteriorated the rutting resistance and weakened the elastic recovery performance of elastomer (CR and SBS) modified bitumen. To ensure the low-temperature performance, the optimum level of WR was 2 wt%. Furthermore, the addition of WR promoted the compatibility and dispersion of CR and SBS modifiers in bitumen.Pavement Engineerin
Synthesis and Properties of New Small Band Gap Conjugated Polymers: Methine Bridged Poly(3,4-ethylenedioxypyrrole)
No full textLaser flash photolysis studies on intra- and intermolecular reactions of some halocarbenes
No full textLaser flash photolysis studies on alpha-methylbenzylchlorodiazirine, n-propylchlorodiazirine, and isopropylchlorodiazirine have been carried out at low temperatures, ranging from 170 to 230 K. The present results, together with those previously obtained with benzylchlorodiazirine and methylchlorodiazirine, provide a direct measurement of the ''by-stander effect'' of alkyl substituents on the C atom in the alpha position of the carbene center. Intermolecular reactions of alpha-methylbenzylchlorocarbene and tetramelhylethylene in isooctane and methylcyclohexane have been measured but this reaction is shown to be too slow to measure by LFP in highly viscous decalin solvent.PT: J; CR: BONNEAU R, 1989, J AM CHEM SOC, V111, P5973 BONNEAU R, 1996, J AM CHEM SOC, V118, P3829 DIX EJ, 1993, J AM CHEM SOC, V115, P10424 FREY HM, 1970, J CHEM SOC A, P1916 GRAHAM WH, 1965, J AM CHEM SOC, V87, P4396 HOUK KN, 1984, J AM CHEM SOC, V106, P4293 JACKSON JE, 1989, TETRAHEDRON LETT, V30, P1335 JACKSON JE, 1994, ADV CARBENE CHEM, V1 LAVILLA JA, 1989, J AM CHEM SOC, V111, P6877 LIU MTH, 1989, J AM CHEM SOC, V111, P6873 LIU MTH, 1990, J AM CHEM SOC, V112, P3915 LIU MTH, 1992, J AM CHEM SOC, V114, P3604 LIU MTH, 1994, ACCOUNTS CHEM RES, V27, P287 LIU MTH, 1994, J PHOTOCH PHOTOBIO A, V84, P133 MOSS RA, 1994, ADV CARBENE CHEM, V1 MOSS RA, 1995, PURE APPL CHEM, V67, P741 MUROV SL, 1973, HDB PHOTOCHEMISTRY NICKON A, 1993, ACCOUNTS CHEM RES, V26, P84 RIDDICK JA, 1970, TECH CHEM, V2, P95 SCHAEFER HF, 1979, ACCOUNTS CHEM RES, V12, P288 STORER JW, 1993, J AM CHEM SOC, V115, P10426 TOMIOKA H, 1984, J AM CHEM SOC, V106, P454 TURRO NJ, 1982, J AM CHEM SOC, V104, P1754 VONSALIS GA, 1968, J PHYS CHEM-US, V72, P752 WHITE WR, 1992, J ORG CHEM, V57, P2841; NR: 25; TC: 16; J9: J AMER CHEM SOC; PG: 4; GA: VE266Source type: Electronic(1
Quantum yield of formation of diazo compounds from the photolysis of diazirines
No full textPT: J; CR: BALLY T, 1994, ANGEW CHEM INT EDIT, V33, P1964 BAYLEY H, 1978, BIOCHEMISTRY-US, V17, P2420 BONNEAU R, 1991, PURE APPL CHEM, V63, P289 BONNEAU R, 1996, J AM CHEM SOC, V118, P3829 BRADLEY GF, 1977, J CHEM SOC P2, P1214 BRINTON RK, 1951, J CHEM PHYS, V20, P1394 CLOSS GL, 1962, J AM CHEM SOC, V84, P4350 FREY HM, 1965, J CHEM SOC, P1700 GANZER GA, 1986, J AM CHEM SOC, V108, P1517 JACKSON JE, 1989, J AM CHEM SOC, V111, P6874 KUPFER R, 1994, J AM CHEM SOC, V116, P7393 LIU MTH, IN PRESS J AM CHEM S LIU MTH, 1987, J ORG CHEM, V52, P4223 MODARELLI DA, 1992, J AM CHEM SOC, V114, P7034 MOSS RA, 1981, TETRAHEDRON LETT, V22, P3749 MOSS RA, 1994, ADV CARBENE CHEM, V1 MULLER E, 1960, CHEM BER, V93, P1541 ROSENBERG MG, 1996, TETRAHEDRON LETT, V37, P3235 SMITH RAG, 1975, J CHEM SOC P2, P686 WHITE WR, 1992, J ORG CHEM, V57, P2841 YAMAMOTO N, 1994, J AM CHEM SOC, V116, P2064; NR: 21; TC: 17; J9: J AMER CHEM SOC; PG: 2; GA: VA026Source type: Electronic(1
Carboxylation of carbenes in low-temperature matrixes
No full textPT: J; CR: ADAM W, 1971, J AM CHEM SOC, V93, P557 ADAM W, 1973, J ORG CHEM, V38, P2269 BAMFORD WR, 1952, J CHEM SOC, P4735 BONNEAU R, 1989, J CHEM SOC CHEM COMM, P510 CHAMPAM OL, 1972, J AM CHEM SOC, V94, P1365 COE PL, 1982, J CHEM SOC CHEM COMM, P362 EISENTHAL KB, 1985, TETRAHEDRON, V41, P1543 GANZER GA, 1986, J AM CHEM SOC, V108, P1517 GOULD IR, 1985, TETRAHEDRON, V41, P1587 GRAHAM WH, 1965, J AM CHEM SOC, V87, P4396 GRILLER D, 1985, TETRAHEDRON, V41, P1525 LIU MTH, 1980, J CHEM SOC CHEM COMM, P1482 LIU MTH, 1987, TETRAHEDRON LETT, V28, P1011 MALTSEV AK, 1985, IAN SSSR KH, P2159 MCMAHON RJ, 1987, J AM CHEM SOC, V109, P2456 MILLIGAN DE, 1962, J CHEM PHYS, V35, P2911 MOSS RA, 1989, ACCOUNTS CHEM RES, V22, P15 PLATZ MS, 1990, KINETICS SPECTROSCOP, P239 PUZA M, 1971, SYNTHESIS-STUTTGART, P481 SANDER W, 1988, ANGEW CHEM INT EDIT, V27, P572 SANDER W, 1988, ANGEW CHEM, V100, P577 SANDER W, 1988, J ORG CHEM, V53, P2091 SANDER W, 1990, ANGEW CHEM INT EDIT, V29, P344 SANDER W, 1990, ANGEW CHEM, V102, P362 SANDER WW, 1987, SPECTROCHIM ACTA A, V43, P637 SANDER WW, 1989, J ORG CHEM, V54, P333 SANDER WW, 1989, J ORG CHEM, V54, P4265 SIEBRAND W, 1986, ACCOUNTS CHEM RES, V19, P238 WHELAND R, 1970, J AM CHEM SOC, V92, P6057; NR: 29; TC: 22; J9: J ORG CHEM; PG: 3; GA: HB875Source type: Electronic(1
Laser Flash Photolysis Studies: 1, 2-Hydrogen Migration to a Carbene
No full textPT: J; CR: ALTMANN JA, 1974, J AM CHEM SOC, V96, P4196 ALTMANN JA, 1975, J AM CHEM SOC, V97, P5217 BODOR N, 1972, J AM CHEM SOC, V94, P9103 BONNEAU R, 1989, J AM CHEM SOC, V111, P5973 BURNETT SM, 1983, CHEM PHYS LETT, V100, P124 CELEBI S, 1993, J AM CHEM SOC, V115, P8613 DIX EJ, 1993, J AM CHEM SOC, V115, P10424 EVANSECK JD, 1990, J PHYS CHEM-US, V94, P5518 FRENKING G, 1984, TETRAHEDRON, V40, P2123 FREY HM, 1962, J CHEM SOC, P2293 FREY HM, 1965, J CHEM SOC, P1700 FREY HM, 1966, ADV PHOTOCHEM, V4, P225 FRIEDMAN L, 1959, J AM CHEM SOC, V81, P5512 GALLO MM, 1992, J PHYS CHEM-US, V96, P1515 HO GJ, 1989, J AM CHEM SOC, V111, P6875 HOFFMANN R, 1968, J AM CHEM SOC, V90, P1485 HOUK KN, 1984, J AM CHEM SOC, V106, P4291 HOUK KN, 1984, J AM CHEM SOC, V106, P4293 HOUK KN, 1985, TETRAHEDRON, V41, P1555 JACKSON JE, 1988, J AM CHEM SOC, V110, P5595 JACKSON JE, 1989, J AM CHEM SOC, V111, P6874 JACKSON JE, 1994, ADV CARBENE CHEM, V1 JONES WM, 1980, REARRANGEMENTS GROUN, V1, P95 KHODABANDEH S, 1993, J PHYS CHEM-US, V97, P4360 KIRMSE W, 1965, ANGEW CHEM INT EDIT, V4, P692 KIRMSE W, 1971, CARBENE CHEM KRAMER KAW, 1962, TETRAHEDRON LETT, P1095 KYBA EP, 1977, J AM CHEM SOC, V99, P8330 LAVILLA JA, 1989, J AM CHEM SOC, V111, P6877 LAVILLA JA, 1990, TETRAHEDRON LETT, V31, P5109 LIU MTH, IN PRESS J PHOTOCHEM LIU MTH, 1985, J CHEM SOC CHEM COMM, P982 LIU MTH, 1986, J PHYS CHEM-US, V90, P75 LIU MTH, 1987, CHEM DIAZIRINES, V1, P111 LIU MTH, 1987, J ORG CHEM, V52, P4223 LIU MTH, 1989, J AM CHEM SOC, V111, P6873 LIU MTH, 1989, J PHYS CHEM-US, V93, P7298 LIU MTH, 1990, J AM CHEM SOC, V112, P3915 LIU MTH, 1990, J CHEM SOC CHEM COMM, P1650 LIU MTH, 1992, J AM CHEM SOC, V114, P3604 LIU MTH, 1992, J ORG CHEM, V57, P2483 LIU MTH, 1992, J PHYS ORG CHEM, V5, P285 LIU MTH, 1993, J PHYS ORG CHEM, V6, P696 LIU MTH, 1994, RES CHEM INTERMEDIAT, V20, P195 MA B, 1994, J AM CHEM SOC, V116, P3539 MANSOOR AM, 1966, TETRAHEDRON LETT, P1733 MODARELLI DA, 1991, J AM CHEM SOC, V113, P8985 MODARELLI DA, 1992, J AM CHEM SOC, V114, P7034 MODARELLI DA, 1993, J AM CHEM SOC, V115, P10440 MODARELLI DA, 1993, J AM CHEM SOC, V115, P470 MOSS RA, 1989, ACCOUNTS CHEM RES, V22, P15 MOSS RA, 1990, J AM CHEM SOC, V112, P1638 MOSS RA, 1990, J AM CHEM SOC, V112, P5642 MOSS RA, 1992, J PHYS ORG CHEM, V5, P104 MOSS RA, 1992, TETRAHEDRON LETT, V33, P4287 MOSS RA, 1993, J CHEM SOC CHEM COMM, P1597 MOSS RA, 1993, J PHYS CHEM-US, V97, P13413 MOSS RA, 1993, J PHYS ORG CHEM, V6, P126 MOSS RA, 1993, TETRAHEDRON LETT, V34, P927 MOSS RA, 1994, ADV CARBENE CHEM, V1 MULLERREMMERS PL, 1985, J AM CHEM SOC, V107, P7275 NICKON A, 1993, ACCOUNTS CHEM RES, V26, P84 NOBES RH, 1980, CHEM PHYS LETT, V74, P269 PLATZ MS, 1994, RES CHEM INTERMEDIAT, V20, P175 RAGHAVACHARI K, 1982, CHEM PHYS LETT, V85, P145 REGITZ M, 1989, METHOD ORGAN CHEM, E, B19 SCHAEFER HF, 1979, ACCOUNTS CHEM RES, V12, P288 SEBURG RA, 1992, J AM CHEM SOC, V114, P7183 SMALL RD, 1977, CHEM PHYS LETT, V50, P431 SMALL RD, 1977, J PHYS CHEM-US, V81, P828 SMALL RD, 1978, CHEM PHYS LETT, V59, P246 STEVENS IDR, 1989, TETRAHEDRON LETT, V30, P481 STORER JW, 1993, J AM CHEM SOC, V115, P10426 SU DTT, 1978, J AM CHEM SOC, V100, P1872 SUGIYAMA MH, 1992, J AM CHEM SOC, V114, P966 TOMIOKA H, 1980, J AM CHEM SOC, V102, P7817 TOMIOKA H, 1984, J AM CHEM SOC, V106, P454 TOMIOKA H, 1986, CHEM LETT, P695 TURRO NJ, 1982, J AM CHEM SOC, V104, P1754 WARNER PM, 1984, TETRAHEDRON LETT, V25, P4211 WHITE WR, 1992, J ORG CHEM, V57, P2841 WIERLACHER S, 1993, J AM CHEM SOC, V115, P8943; NR: 82; TC: 56; J9: ACCOUNT CHEM RES; PG: 8; GA: PL566Source type: Electronic(1
A nonspectroscopic method to determine the photolytic decomposition pathways of 3-chloro-3-alkyldiazirine: Carbene, diazo and rearrangement in excited state
No full textC-60 acts as a mechanistic probe for the formation of carbene, diazo compound, and for the rearranged product via the excited state in the photolysis of 3-chloro-3-isopropyldiazirine and 3-chloro-3-chloromethyldiazirine. The carbene adds to C-60 to form methanofullerene, whereas the diazo compound adds to C-60 to form fulleroid. The olefin product arises as a result of the rearrangement in the excited state.PT: J; CR: AKASAKA T, 1999, J ORG CHEM, V64, P566 AKASAKA T, 1999, ORG LETT, V1, P1509 AKASAKA T, 2000, J AM CHEM SOC, V122, P7134 ARENAS JF, 2002, J AM CHEM SOC, V124, P1728 BECKE AD, 1988, PHYS REV A, V38, P3098 BECKE AD, 1993, J CHEM PHYS, V98, P5648 BONNEAU R, 1996, J AM CHEM SOC, V118, P3829 BONNEAU R, 1996, J AM CHEM SOC, V118, P7229 BRINKER U, 1994, ADV CARBENE CHEM, V1 BRINKER U, 1998, ADV CARBENE CHEM, V2 FRISCH MJ, 1998, GAUSSIAN 98 GRAHAM WH, 1965, J AM CHEM SOC, V87, P4396 HIRSCH A, 1993, CHEM BER, V126, P1061 JACKSON JE, 1988, J AM CHEM SOC, V110, P595 LAVILLA JA, 1989, J AM CHEM SOC, V111, P6877 LAVILLA JA, 1989, J AM CHEM SOC, V111, P712 LEE C, 1988, PHYS REV B, V37, P785 LIU MTH, 1987, CHEM DIAZIRINES, V1 LIU MTH, 1987, CHEM DIAZIRINES, V2 LIU MTH, 1996, J AM CHEM SOC, V118, P8098 MARTIN N, 1998, CHEM REV, V98, P2527 MODARELLI DA, 1992, J AM CHEM SOC, V114, P7034 PIETRO WJ, 1982, J AM CHEM SOC, V104, P5039 PLATZ MS, 1994, RES CHEM INTERMEDIAT, V20, P175 SCHICK G, 1998, TETRAHEDRON, V54, P4283 WHITE WR, 1992, J ORG CHEM, V57, P2841; NR: 26; TC: 8; J9: J AM CHEM SOC; PG: 4; GA: 582NTSource type: Electronic(1
Benzylchlorocarbene: origins of Arrhenius curvature in the kinetics of the 1,2-H shift rearrangement
No full textBenzylchlorocarbene (1, BCC) was generated photochemically from benzylchlorodiazirine (2) in isooctane, methylcyclohexane (MCH), and tetrachloroethane (TCE) at temperatures from similar to 30 to -75 degrees C. At -70 degrees C in isooctane, the identified products included Z/E-beta-chlorostyrenes 4 (46.6%), alpha-chlorostyrene 5 (2.4%), 1,1-dichloro-2-phenylethane 6 (1.9%), a BCC-isooctane insertion product 8 (5.5%), carbene dimers 9 (3.8%), and azine 3 (30%). The significant incursion of intermolecular products 3, 8, and 9 implies that laser flash photolytic (LFP) kinetic data for the decay of BCC obtained at low temperature is biased and should not be employed in Arrhenius analyses. Accordingly, previously obtained curved Arrhenius correlations for BCC do not necessarily implicate quantum mechanical tunneling (QMT) in the 1,2-H shift rearrangement of BCC to 4. Similarly in MCH, where BCC affords a solvent insertion product in similar to 44-53% yield, the curved Arrhenius correlation (Figure 1) cannot be readily interpreted. In polar solvents such as TCE, clean H-shift reactions of BCC are obtained even at -71 degrees C; an Arrhenius correlation of LFP kinetic data is linear from 3 to -71 degrees C (Figure 2), affording E-a = 3.2 kcal mol(-1) and log A = 10.0 s(-1). Therefore, QMT does not appear to play a major role in the 1,2-H shift rearrangement of BCC at ambient or near ambient temperature in solution.PT: J; CR: BONNEAU R, 1996, J AM CHEM SOC, V118, P3829 DEAN JA, 1992, LANGES HDB CHEM DIX EJ, 1993, J AM CHEM SOC, V115, P10424 DOX AW, 1941, ORG SYNTH, V1, P5 GRAHAM WH, 1965, J AM CHEM SOC, V87, P4396 ISAACS NS, 1995, PHYSICAL ORGANIC CHE, P304 JACKSON JE, 1988, J AM CHEM SOC, V110, P5595 KAZANIS S, 1991, J PHYS CHEM-US, V95, P4430 KEATING AE, 1997, COMMUNICATION 0804 LAVILLA JA, 1989, J AM CHEM SOC, V111, P6877 LAVILLA JA, 1990, TETRAHEDRON LETT, V31, P5109 LIU MTH, 1984, TETRAHEDRON, V40, P887 LIU MTH, 1985, CHEM COMMUN, P982 LIU MTH, 1985, J ORG CHEM, V50, P3218 LIU MTH, 1990, J AM CHEM SOC, V112, P3915 LIU MTH, 1992, J AM CHEM SOC, V114, P3604 LIU MTH, 1992, J PHOTOCH PHOTOBIO A, V63, P115 LIU MTH, 1994, ACCOUNTS CHEM RES, V27, P287 LIU MTH, 1994, J PHOTOCH PHOTOBIO A, V84, P133 MODARELLI DA, 1992, J AM CHEM SOC, V114, P7034 MODARELLI DA, 1993, J AM CHEM SOC, V115, P470 MOSS RA, 1987, J AM CHEM SOC, V109, P4341 MOSS RA, 1990, J AM CHEM SOC, V112, P1638 MOSS RA, 1994, ADV CARBENE CHEM, V1, P59 MOSS RA, 1996, J AM CHEM SOC, V118, P12588 MOSS RA, 1997, CHEM COMMUN 0321, P617 MOSS RA, 1997, TETRAHEDRON LETT, V38, P7049 STORER JW, 1993, J AM CHEM SOC, V115, P10426 SUGIYAMA MH, 1992, J AM CHEM SOC, V114, P966 TOMIOKA H, 1984, J AM CHEM SOC, V106, P454 WHITE WR, 1992, J ORG CHEM, V57, P2841 WIERLACHER S, 1993, J AM CHEM SOC, V115, P8943 YEN VQ, 1962, ANN CHIM, V7, P785; NR: 33; TC: 8; J9: J ORG CHEM; PG: 7; GA: ZM109Source type: Electronic(1
Real Exchange Rate in China : A Long-run Perspective
Full text linkThis paper investigates the RMB exchange rate from a long-run viewpoint. Whether Chinas rapid economic growth brought about real exchange rate appreciation between 1975 and 2002 is empirically examined, based on a supply-side model, the BalassaSemuelson Hypothesis (BSH). The same test is conducted on Japan, Hong Kong, Korea, Malaysia, Singapore, Thailand, the Philippines, Indonesia and India. Our result indicates that the BSH only exists where the industrial structure has been upgraded and the economy has been successfully transformed from an agricultural economy to a manufacturing economy. Interestingly, China, among those where the BSH does not present, appears to be upgrading its industrial and trade structure. We then try to answer the question of why past rapid growth has no significant relationship with the RMB real exchange rate and what factors are underlying the trend of the RMB real exchange rate. We expect an appreciating trend of RMB real exchange rate in the foreseeable future, presuming that Chinas industrial upgrading process continues and the factors pertaining to the BSHs prediction, such as rise of wage rates in both tradables and nontradables, become more significant.RMB real exchange rate, economic growth
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