In this article, we designed and synthesized the thionated NpImidazole derivatives BS NS, new heavy-atom-free photosensitizers, which efficiently generate a triplet excited state with high singlet oxygen quantum yield. The introduction of C═S bond to core is essential for increasing spin–orbit coupling (SOC). fluorescence emission NS was quenched at standard ambient temperature, accompanied increase in ISC process from states via thionation. showed negligible dark cytotoxicity against HeLa...

Using classical molecular dynamics simulations, the 2D infrared (IR) spectroscopy of CN− solvated in D2O is investigated. Depending on force field parametrizations, most which are based multipolar interactions for molecule, frequency-frequency correlation function and observables computed from it differ. Most notably, models multipoles TIP3P water yield quantitatively correct results when compared with experiments. Furthermore, recent finding that T1 times sensitive to van der Waals ranges...

In this study, the mechanism of self-initiation in spontaneous thermal polymerization ethyl and n-butyl acrylate is explored using first-principles calculations. Density functional theory (with B3LYP 6-31G* basis set) was used to study [4 + 2] [2 cycloaddition reactions on singlet triplet potential energy surfaces. Diels−Alder (DA) dimers [6-ethoxy-2-ethoxycarbonyl-3,4-dihydro-2H-pyran (EDP)] [6-butoxy-2-butoxycarbonyl-3,4-dihydro-2H-pyran (BDP)] were found form surface via concerted pathway...

The vibrationally excited cyanide ion (CN(-)) in H2O or D2O relaxes back to the ground state within several tens of picoseconds. Pump-probe infrared spectroscopy has determined relaxation times T1 = 28 ± 7 and 71 3 ps D2O, respectively. Atomistic simulations this process using nonequilibrium molecular dynamics allow determination whether it is possible at all describe such a process, what level accuracy force fields required, information can be used understand mechanisms underlying...

Due to the concern for COVID-19, universities in Korea switched online teaching most chemistry courses spring semester, 2020. While lectures have been available a small number of previous semesters, it is unprecedented that should be given online. In this communication, we describe how higher education has made 2020, mainly based on experience author and colleagues, address insights gained would like share. Admittedly, limited, there are still unresolved challenges.

This paper presents computational evidence for the occurrence of diradical mechanism self-initiation in thermal polymerization methyl methacrylate. Two mechanisms interest were explored with first-principles density functional theory calculations. Singlet and triplet potential energy surfaces constructed. The formation two Diels−Alder adducts, cis- trans-dimethyl 1,2-dimethylcyclobutane-1,2-dicarboxylate dimethyl 2-methyl-5-methylidene-hexanedioate, on singlet surface was identified....

This computational study deals with the mechanism of spontaneous initiation in thermal polymerization alkyl acrylates (e.g., methyl, ethyl, and n-butyl acrylate). The is presently still unknown. Density-functional theory (DFT) Møller−Plesset (MP2) calculations are used to explore Flory Mayo mechanisms self-initiation methyl acrylate. On singlet surface, a low-barrier, concerted [4 + 2] Diels−Alder for formation dihydropyran adduct (DA) high-barrier nonconcerted [2 diradical (•M2s•) dimethyl...

Beyond statin therapy for reducing low density lipoprotein cholesterol (LDL-C), additional therapeutic strategies are required to achieve more optimal reduction in cardiovascular risk among diabetic patients with dyslipidemia. To evaluate the effects and safety of combined treatment omega-3 fatty acids dyslipidemic type 2 diabetes, we conducted a randomized, open-label study Korea. Patients persistent hypertriglyceridemia (≥200 mg/dL) while taking at least 6 weeks were eligible. Fifty-one...

The evaluation of hydration free energies is a sensitive test to assess force fields used in atomistic simulations. We showed recently that the vibrational relaxation times, 1D- and 2D-infrared spectroscopies for CN(-) water can be quantitatively described from molecular dynamics (MD) simulations with multipolar slightly enlarged van der Waals radii C- N-atoms. To validate such an approach, present work investigates solvation energy cyanide using MD accurate electrostatics. It found larger...

Molecular dynamics (MD) simulations together with accurate physics-based force fields are employed to determine the mobility of atomic oxygen in amorphous ice at low temperatures, characteristic for conditions interstellar ices. From it is found that ranges from 60 480 angstroms2 ns(-1) temperatures between 50 and 200 K. Hence, establish mobile a certain degree chemical mechanism water formation involving realistic scenario. This also confirmed by computed migration barriers diffusion...

We prepared the monomer PCDA-HP composed of 5-hydroxy-N1,N3-bis(pyridin-2-ylmethyl)isophthalamide (HP) as a cadmium ion tweezer and then polymerized them to form polydiacetylene (PDA)-based sensor (PDA-HP), which displayed selective sensitive colorimetric fluorometric change upon addition (Cd2+) at both pH 7.4 6.8. The PDA-HP polymer was highly for Cd2+ over other metal ions with change. In addition, chemosensor also showed red fluorescence in presence Naked-eye detection accomplished an...

The performance of organic thin film transistors (OTFTs) strongly depends on the surface states gate insulator. In this study, plasma treatment prior to deposition pentacene has been applied and effects investigated. Overall plasma-treated OTFTs improved. particular, field-effect mobility enhanced 0.05 cm2/V·s which is 10 times larger than that as-deposited OTFTs. Moreover, standard deviation each parameter variation was reduced by exposure, implies renders uniform across entire wafer area....

Atomic forces are calculated for first-row monohydrides and carbon monoxide within electronic quantum Monte Carlo (QMC). Accurate efficient achieved by using an improved method moving variational parameters in QMC. Newton's with singular value decomposition (SVD) is combined steepest-descent (SD) updates along directions rejected the SVD, after initial SD steps. Dissociation energies diffusion QMC agree well experiment. The atomic quantitatively potential-energy surfaces, demonstrating...

Patients with subclinical hypothyroidism (SHT) are common in clinical practice. However, the significance of SHT, including prognosis, has not been established. Further clarifying SHT will be critical devising a management plan and treatment guidelines for patients. Thus, aim this study was to investigate prognostic factors SHT.We reviewed medical records Korean patients who visited endocrinology outpatient clinic Severance Hospital from January 2008 September 2012. Newly-diagnosed were...

The infrared (IR) spectroscopy and ligand migration of photodissociated nitric oxide (NO) in around the active sites myoglobin (Mb) are investigated. A distributed multipolar model for open-shell systems is developed used, which allows one to realistically describe charge distribution diatomic probe molecule. IR spectra were computed from trajectories two conformational substates at various temperatures. lines narrow (width 3-7 cm(-1) 20-100 K), agreement with experimental observations where...

Printing technologies were applied to fabricate a flexible organic thin-film transistor (OTFT) backplane for electrophoretic displays (EPDs). Various printing processes adopted maximize the figures of each layer OTFT: screen combined with reverse offset gate electrodes and scan bus lines Ag ink, inkjet source/drain glycerol-doped Poly (3,4-ethylenedioxythiophene): (styrenesulfonate) (PEDOT:PSS), semiconductor Triisopropylsilylethynyl (TIPS)-pentacene, pixel paste. A mobility 0.44 cm2/V s was...

The ability to detect hypochlorite (HOCl/ClO − ) in vivo is of great importance identify and visualize infection. Here, we report the use imidazoline-2-thione ( R 1 SR 2 probes, which act both sense ClO kill bacteria. N C=S moieties can recognize among various typical reactive oxygen species (ROS) turn into imidazolium IR via desulfurization. This was observed through UV–vis absorption fluorescence emission spectroscopy, with a high quantum yield (Փ F = 43–99%) large Stokes shift (∆v∼115...

Mixed ices play a central role in characterizing the origin, evolution, stability and chemistry of planetary ice surfaces. Examples include polar areas Mars, crust Jupiter moon Europa, or atmospheres planets their satellites, particularly outer solar system. Atomistic simulations using accurate representations interaction potentials have recently shown to be suitable quantitatively describe both, mid- far-infrared spectrum mixed H2O/CO amorphous ices. In this work, molecular dynamics are...

In this study we developed a simple ink-jet process for 6,13-bis(triisopropylsilylethynyl)-pentacene (TIPS-pentacene), which is known as high-mobility soluble organic semiconductor, to achieve relatively and high-uniformity performance large-area applications. We analyzed the behavior of fluorescent particles in droplets applied results determining method controlling TIPS-pentacene molecules. The grain morphology varied depending on temperature during drying. were able obtain large uniform...