Search Results - "Koopmans, J R"

Modeling Foam Growth in Thermoplastics by Koopmans, R. J., den Doelder, J. C. F., Paquet, A. N.

“…Foaming of thermoplastic polymers is a complex process. Here models are presented that address the viscoelastic character of the thermoplastic melt during the…”
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Quantitative modelling of HDPE spurt experiments using wall slip and generalised Newtonian flow by den Doelder, C.F.J., Koopmans, R.J., Molenaar, J.

“…A quantitative model to describe capillary rheometer experiments is presented. The model can generate `two-branched' discontinuous flow curves and the…”
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The effect of molar mass distribution on extrudate swell of linear polymers by den Doelder, C.F.J., Koopmans, R.J.

“…Extrudate swell is an important viscoelastic feature of polymer melt processing. Experimental work with linear polymers has identified extrudate swell to…”
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The "sharkskin effect" in polymer extrusion by Koopmans, Rudolf J., Molenaar, Jaap

“…Melt flow instabilities associated with surface defects for polymer extrudates and commonly referred to as the “Sharkskin Effect,” are modeled. The relaxation…”
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Comparing the wall slip and the constitutive approach for modelling spurt instabilities in polymer melt flows by Den Doelder, C.F.J., Koopmans, R.J., Molenaar, J., Van de Ven, A.A.F.

“…At high flow rates during polymer melt extrusion, pressure oscillations can be observed. The phenomenon is usually referred to as spurt, due to the…”
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Association between Alcohol Use and Smoking in Adolescent and Young Adult Twins: A Bivariate Genetic Analysis by Koopmans, Judith R., van Doornen, Lorenz J.P., Boomsma, Dorret I.

“…The association between alcohol use and smoking was examined in a large population‐based sample of Dutch twins consisting of three age groups; young adolescent…”
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Modeling foam growth in semi-crystalline thermoplastics by DEN DOELDER, C. F. J, SAMMLER, R. L, KOOPMANS, R. J, PAQUET, A. N

“…The accurate description of the rapidly changing viscoelastic character of the gas-laden polymer melt during the expansion phase of foam development is one of…”
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Genetic and social influences on starting to smoke: a study of Dutch adolescent twins and their parents by Boomsma, D I, Koopmans, J R, Van Doornen, L J, Orlebeke, J F

“…In a study of 1600 Dutch adolescent twin pairs we found that 59% of the inter-individual variation in smoking behaviour could be attributed to shared…”
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A religious upbringing reduces the influence of genetic factors on disinhibition: evidence for interaction between genotype and environment on personality by Boomsma, D I, de Geus, E J, van Baal, G C, Koopmans, J R

“…Information on personality, on anxiety and depression and on several aspects of religion was collected in 1974 Dutch families consisting of adolescent and…”
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The effect of molar mass distribution on extrudate swell of linear polymers: 4th International workshop on Nonequilibrium Thermodynamics and Complex Fluids by DEN DOELDER, C. F. J, KOOPMANS, R. J

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The genetics of smoking initiation and quantity smoked in Dutch adolescent and young adult twins by Koopmans, J R, Slutske, W S, Heath, A C, Neale, M C, Boomsma, D I

“…Not much is known about the genetic and environmental determinants of various aspects of substance use in adolescents. This study examined whether the…”
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Familial resemblances in alcohol use : genetic or cultural transmission ? by KOOPMANS, J. R, BOOMSMA, D. I

“…Resemblances between parents and children for alcohol use can be due both to cultural transmission and genetic inheritance. We examined the genetic and…”
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The influence of religion on alcohol use initiation: evidence for genotype X environment interaction by Koopmans, J R, Slutske, W S, van Baal, G C, Boomsma, D I

“…We examined the possible role of religious upbringing as a mediator of the shared environmental influences and as a moderator of the genetic influences on the…”
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Onset of the sharkskin phenomenon in polymer extrusion by Molenaar, J., Koopmans, R. J., den Doelder, C. F. J.

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A multivariate genetic analysis of sensation seeking by Koopmans, J R, Boomsma, D I, Heath, A C, van Doornen, L J

“…The genetic architecture of sensation seeking was analyzed in 1591 adolescent twin pairs. Individual differences in sensation seeking were best explained by a…”
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Netherlands twin family study of anxious depression (NETSAD) by Boomsma, D I, Beem, A L, van den Berg, M, Dolan, C V, Koopmans, J R, Vink, J M, de Geus, E J, Slagboom, P E

“…In a longitudinal study of Dutch adolescent and young adult twins, their parents and their siblings, questionnaire data were collected on depression, anxiety…”
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Association between alcohol use and smoking in adolescent and young adult twins: a bivariate genetic analysis by Koopmans, J R, van Doornen, L J, Boomsma, D I

“…The association between alcohol use and smoking was examined in a large population-based sample of Dutch twins consisting of three age groups; young adolescent…”
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Left-Handedness in Twins: Genes or Environment? by Orlebeke, Jacob F., Knol, Dirk L., Koopmans, Judith R., Boomsma, Dorret I., Bleker, Otto P.

“…Twin family data can cast light on the longstanding problem about the influences of genes and environment on the etiology of left-handedness. Therefore, hand…”
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Comparison of the time courses and potencies of the vasodilator effects of nifedipine and felodipine in the human forearm by van der Lee, R, Pfaffendorf, M, Koopmans, R P, van Lieshout, J J, van Montfrans, G A, van Zwieten, P A

“…In a previous study we investigated the differential time courses of the vasodilator effect of various calcium antagonists (CA) in small isolated rat…”
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