data reduction, 374 dative bond , 374 Dauben–Salem–Turro rules, 374 daughter ion in mass spectrometry, 375 daughter product in radiochemistry , 375 Davydov splitting (factor-group splitting), 375 day, 375 de Mayo reaction, 376 de-electronation [obsolete] , 376 deactivation, 376 dead time correction in radioanalytical chemistry, 376 dead time in radioanalytical chemistry , 377 dead time of an analyser , 377 dead-volume [obsolete] in chromatography , 377 debye, 377 Debye–Hückel equation, 377 deca, 378 decadic absorbance, , 378 decay chain, 378 decay constant, 379 decay curve, 379 decay rate in atmospheric chemistry , 379 decay scheme in radioanalytical chemistry , 379 decay time in heterogenous catalysis , 380 deci, 380 decibel, 380 decomposition, 380 decontamination factor in liquid- liquid distribution , 380 definitive method, 380 deflection (for a precision balance), 381 deflocculation (peptization), 381 degeneracy, 381 degenerate chain branching, 381 degenerate orbitals, 382 degenerate rearrangement, 382 degree Celsius, 382 degree Fahrenheit, 382degree of arc , 383 degree of association of a micelle, 383 degree of crystallinity of a polymer , 383 degree of dissociation, 383 degree of ionization, 384 degree of polymerization, 384 degree of reaction, , 384 degrees of cistacticity and transtacticity, 384 degrees of freedom, , 384 degrees of triad isotacticity, syndiotacticity, and heterotacticity , 385 dehydroarenes, 385 dehydrobenzenes, 385 delayed coincidence, 385 delayed coke, 385 delayed coking process, 386 delayed fluorescence, 386 delayed luminescence, 387 delayed neutrons, 387 deliquescence, 387 delocalization, 388 delocalization energy (DE), 388 delocalization in theoretical organic chemistry , 389 demister, 389 denaturation of a macromolecule , 389 denaturation of alcohol , 389 dendrite, 390 denitrification, 390 densification, 390 density, , 390 density inversion in solvent extraction , 390 density of states, , , 391 denticity, 391 denuder system (tube or assembly), 391 deodorizer in atmospheric chemistry , 391 deoxyribonucleic acids (DNA), 391 depolarization of scattered light, 392 depolarizer [obsolete] , 392 depolymerization, 392 deposition in atmospheric chemistry, 392 deposition velocity in atmospheric chemistry , 393 depsides, 393 depsipeptides, 393 depth of penetration of light , 394 depth profile, 394