• Mass Spectrometry Letters
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• v.2 no.1
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• pp.24-27
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• 2011

Hyperthermal ion/surface collisions of bromotoluene radical cations were studied using perfluorinated (F-SAM) and hydroxyl-terminated (OH-SAM) self-assembled monolayer surfaces in a tandem mass spectrometer with BEEQ geometry. The isomers were differentiated by ion abundance ratios taken from surface-induced dissociation (SID). The dissociation rate followed the order of ortho > meta > para isomers. The peak abundance ratio of m/z 51 to m/z 65 showed the best result to discern the isomers. A dissociation channel leading to tolylium ion was suggested to be responsible for the pronounced isomeric differences. The capability of SID to provide high-energy activation with narrow internal energy distribution may have channeled the reaction into the specific dissociation pathway, also facilitating small differences in reaction rates to be effective in the spectral time window of this experiment. All of the molecular ions experiencing reactive collisions with the F-SAM surface undergo transhalogenation, in which a fluorine atom on the surface replaces the bromine in the incoming ions. This reactive collision was dependent on the laboratory collision energy occurring in ca. 40.75 eV range.

• The Journal of Industrial Distribution & Business
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• v.10 no.11
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• pp.35-47
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• 2019

Purpose: Current study focused on investigating the effects of the self-dissociation as a thought in which consumers dis-identify or dissociate with the threatened in-group and the escapism as a tendency of consumers' distracting themselves and avoiding their thoughts about the in-group under severe but adoptable criticism by turning their attention elsewhere on across-domain compensatory consumption intention. And It explored not only the positive roles of undesirability thought against the in-group in consumers' forming the self-dissociation and the escapism, but also the effects of negative emotion to the in-group felt at the place of being exposed to the criticism against the in-group on the escapism. Research design, data, and methodology: The experiment was performed with the in-group-threatening single factor within-subject design. Questionnaire data were collected from 196 undergraduate students, and the data were used to testing research hypotheses by structural equation model of Amos 21.0. Results: First, both the self-dissociation of consumers' dis-identifying with the in-group criticized severely by others and the escapism of their deliberately directing their thoughts and distracting their attention away from thinking the in-group positively influenced on the across-domain compensatory consumption intention. Second, the negative emotion positively influenced on the escapism. Third, the undesirability thought to the in-group under the severe criticism positively effected on the self-dissociation as well as the escapism. Putting in the nutshell, the findings of this study are consistent with the idea that consumers can overcome the negative self-discrepancy on one dimension of their social identity by distracting themselves and avoiding thinking about the threatened in-group to find meaning on another dimension which might lead them to the place of doing the across-domain compensatory consumption. Conclusions - Focusing on the results of this study, checking which aspects of consumers' social identity are linked to products or brands is at issue to marketers when the consumers are faced with the criticism against the in-group. The marketers should build the messages about their products or brand not related to the checked aspects, and communicate the messages, to lead the consumers to the place of doing the across-domain compensatory consumption by their products or brands.

• Proceeding of EDISON Challenge
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• 2014.03a
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• pp.115-125
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• 2014

We investigate dissociation of diatomic molecules and anions using density functional theory (DFT) and density-corrected density functional theory (DC-DFT). We scan the potential energy curve of CH, NH and NO neutral molecule and its anion with both DFT and DC-DFT (in form of Hartree-Fock DFT, HF-DFT) using various functionals. Using CCSD(T) results as reference, we perform the error decomposition scheme recently proposed by Kim et al. The results show while most neutrals are $functio{\acute{n}}al$ error $domi{\bar{n}}ating$ normal calculations, $CH^-$ and $NO^-$ anions are density-driven error dominating abnormal calculations. In case of $NH^-$, traditional DFT goes to a wrong dissociation limit indicating abnormality, but both HF-DFT and CCSD(T) results need further investigation due to the kinks on the curve.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.123.2-123.2
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• 2011

Self-preservation effect was identified by means of macroscopic dissociation experiments after keeping natural gas hydrate samples at 258 K for 15 days. The hydrate samples were formed using synthetic natural gas hydrate whose compositions are 90% $CH_4$, 7% $C_2H_6$, and 3% $C_3H_8$. In addition, during the formation, heavy hydrocarbons of propane and ethane are found to occupy hydrate cages in a more favorable way than methane so as to change the gas composition after hydrate formation. Experimental results obtained in this study can provide useful information on applications of natural gas hydrate for storing or transporting natural gas in the form of solid hydrate.

• Ocean and Polar Research
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• v.26 no.3
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• pp.515-521
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• 2004

The processes of formation and dissociation of gas hydrates were investigated by monitoring pressure and temperature variations in a pressure cell in order to understand the kinetic behavior of gas hydrate and the controlling factors fur the phase transition of gas hydrate below freezing. Gas hydrates were made kom guest gases ($CH_4,\;CO_2$, and their mixed-gas) and fine ice powder. We found that formation and dissociation speeds of gas hydrates were not controlled by temperature and pressure conditions alone. The results of this study suggested that pressure levels at the formation of mixed-gas hydrate determine the transient equilibrium pressure itself.

• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.11-15
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• 2017

We present a study of transition metal compounds using density functional theory (DFT), and density-corrected density functional theory(DC-DFT). By replacing the self-consistent density with that obtained from Hartree-Fock calculation, i.e., HF-DFT, the abnormality driven by self-interaction error is removed in several important cases. We discuss when and how HF-DFT works by examining 3d orbital dimers using approximate functionals and by comparing the results from self-consistent-DFT and HF-DFT with experimental values.

• Journal of the Korean Chemical Society
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• v.45 no.5
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• pp.401-412
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• 2001

The geometrical parameters, vibrational frequencies, and dissociation energies for $H_{2n+1}^+$ (n=1~6) clusters have been investigated using high level ab initio quantum mechanical techniques with large basis sets. The equilibrium geometries have been optimized at the self-consistent field (SCF), the single and double excitation configuration interaction (CISD), the coupled cluster with single and double excitation (CCSD), and the CCSD with connected triple excitations [CCSD(T)] levels of theory. The highest levels of theory employed in this study are TZ2P+d CCSD(T) up to $H^+_g$ and TZ2P CCSD(T) for $H_{11}^+$ and $H_{13}^+$. Harmonic vibrational frequencies are also determined at the SCF level of theory with various basis sets and confirm that all the optimized geometries are true minima. The dissociation energies, $D_e$, for $H_{2n+1}^+$ (n=26) have been predicted using energy differences at each optimized geometry and zero-point vibrational energies(ZPVEs) have been considered to compare with experimental dissociation energies, $D_0$.

• Bulletin of the Korean Chemical Society
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• v.30 no.7
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• pp.1470-1474
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• 2009

Thermal and photochemistry of methyl iodide ($CH_3I)\;adsorbed\;on\;D_2O$ ice film on Cu(111) at 100 K were studied using temperature-programmed desorption (TPD) time-of-flight mass spectrometry (TOF-MS), X-ray and ultraviolet photoelectron spectroscopies. On the basis of TPD, multilayer and monolayer $CH_3I$ molecules desorb from $D_2O$ ice layer at 120 and 130 K, respectively. Photo-irradiation at 100 K exhibits dramatic changes in the TPD and I $3d_{5/2}\;XPS\;of\;CH_3I$ on ice film, due to a dramatic dissociation of $CH_3I$. The dissociation is likely activated by solvated electrons transferred from the metal substrate during photo-irradiation. No other photo-initiated reaction products were found within our instrumental detection limit. During photo-irradiation, the $CH_3I$, $CH_3$ and I could be trapped (or solvated) in ice film by rearrangement (and self-diffusion) of water molecules. A newly appeared parent molecular desorption peak at 145 K is attributed to trapped $CH_3I$. In addition, the $CH_3$ and I may diffuse through ice and chemisorb on Cu(111), indicated by TPD and I $d_{5/2}$ XPS taken with photo-irradiation time, respectively. No molecular ejection was found during photo-irradiation at 100 K. The work functions for $CH_3I/Cu(111),\;D_2O/Cu(111)\;and\;CH_3I/D_2$O/Cu(111) were all measured to be about 3.9 eV, 1.0 eV downward shift from that of clean Cu(111).

• Bulletin of the Korean Chemical Society
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• v.23 no.2
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• pp.245-252
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• 2002

The computationally simple quantum mechanical method (VSCF-DWB-IOS) has been applied to studying the Ar-$CO_2$ vibrational predissociation phenomenon. The new methodology utilizes the vibrational self-consistent field method to determine the vibrational structure of the van der Waals complex, the distorted-wave Born approximation for dissociating process, and the infinite-order sudden approximation for the continuum dissociating product of $CO_2$. The dissociation due to the coupling of the symmetric stretching vibrational motion of $CO_2$ with the motion of the Ar van der Waals mode has been extensively investigated. The lifetimes of transient excited vibrational states, linewidths of absorption peak, and the rotational state distributions of the product, $CO_2$ have been computed. It has been found that the lifetime of the Ar-$CO_2$ in excited vibrational state is very long compared with that of triatomic van der Waals complexes and the product $CO_2$ carries a major portion of dissociation energy as a rotational energy.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.13 no.1
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• pp.3-14
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• 2002

Childhood psychic trauma appears to be a crucial factor in the development of serious disorders both in childhood and in adulthood. Traumatized children show strong tendency to revisualize or re-feel a traumatic events. Play and behavioral reenactments are frequent manifestations of both the single blow and the long-standing traumas in childhood. Those children who suffer the results of single, intense terror appear to exhibit detailed memory, retrospective reworkings and misperceptions. In long-standing or repetitive trauma, children would show psychic numbing, self-hypnosis, dissociation and rage. Child's brain is undergoing critical and sensitive periods of differentiation. During this time, developing central nervous system is exquisitely sensitive to stress. Stressor-activated neurotransmitters and hormones can play major roles in neurogenesis, migration, synaptogenesis, and neurochemical differentiation. Internal opiate system operates in some trauma and causes the victim to fail to respond, to avoid, to shut off feelings. Evidence is also accumulating in traumatology that dysfuntion of locus coeruleus and ventral tegmental neucleus system leads to catecholamine receptors hypersensitivity. This change result in hypervigilance, increased startle, affective lability, and increased autonomic nervous system hyperreactivity. Another site of action of trauma on the brain is hypothalamic-pituitary-adrenal axis. Individuals with PTSD do not have enough cortisol to halt the alarm reaction. When children are exposed to long-standing extreme events, massive attempts to protect the psyche and to preserve the self are put into gear. These developmental traumas mobilize various kinds of defense mechanisms. Massive denial, dissociation, self anesthesia, identification with aggressor and aggression turned against the self often lead to profound character changes in the youngsters.