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Zeolites with appropriately narrow pore apertures can kinetically enhance the selective adsorption of CO2 over N-2. Here, we showed that the exchangeable cations (e.g., Na' or K) on zeolite ZK-4 play, an important role in the CO2 selectivity. Zeolites NaK ZK-4 with Si/Al = 1.8-2.8 had very high CO2 selectivity when an intermediate number of the exchangeable cations were K+ (the rest being Na+) Zeolites NaK ZK-4 with Si/Al = 1.8 had high CO, uptake capacity and very high CO2-over-N-2 selectivity (1190). Zeolite NaK ZK-4 with Si/A1 = 2.3 and 2.8 also had enhanced CO2 selectivity with an intermediate number of K cations. The high CO, selectivity was related to the I(' cation in the 8 -rings of the alpha-cage, together with Na+ cations in the 6 -ring, obstructing the diffusion of N2 throughout the zeolite. The positions of the K+ cation in the 8 -ring moved slightly (max 0.2 angstrom) toward the center of the a-cage upon the adsorption of CO2, as revealed by in situ X-ray diffraction. The CO2-over-N-2 selectivity was somewhat reduced when the number of K+ cations approached 100%. This was possibly due to the shift in the IC' cation positions in the 8 -ring when the number of Na+ was going toward 0%, glowing N, diffusion through the 8 -ring. According to 'm situ infrared spectroscopy, the amount of chemisorbed CO2 was reduced on zeolite ZK-4s with increasing Si/Al ratio. In the context of potential applications, a kinetically enhanced selection of CO2 could be relevant for applications in carbon capture and bio- and natural gas upgrading.

Alkoxyhalogenation of dihalostyrenes with allyl or propargyl alcohol and N-bromosuccinimide or crystalline iodine in the presence of clinoptilolite [(NaK)4CaAl6Ci30O72] afforded the corresponding unsaturated β-halo ethers with high yields.

A procedure has been proposed for the synthesis of 2-aryl-5-methyl-1,4-dioxanes by alkoxyiodination of halogen-substituted styrenes with allyl alcohol in the presence of crystalline iodine, (NaK)4CaAl6Si30O72 clinoptilolite, and silicotungstic acid sodium salt Na4SiW12O40·19H2O in aqueous medium.

Notch Activation Complex Kinase, NACK, is a component of the Notch transcriptional machinery critical to Notch-mediated tumorigenesis. However, the mechanism by which NACK regulates the Notch-mediated transcription is not well understood. Here we demonstrate that NACK binds and hydrolyses ATP and that only ATP-bound NACK is able to bind to the Notch Ternary Complex (NTC). Considering this we sought to identify inhibitors of this ATP-Dependent function and, using computational pipelines, discovered the first small molecule inhibitor of NACK, Z271-0326, that directly blocks the activity of Notch-mediated transcription and shows potent antitumor activity in PDX mouse models. In conclusion, we have discovered the first inhibitor that holds promise for efficacious treatment of Notch-driven cancers by blocking the Notch downstream NTC activity.

Alkoxyiodination of alkyl allyl ethers with elemental iodine in allyl and propargyl alcohols in the presence of clinoptilolite [(NaK)4CaAl6Si30O72] gave the corresponding alkyl 2-(allyloxy or propargyloxy)-3-iodopropyl ethers in high yields.

Zeolite |Na12|-A is a commercial adsorbent, and its CO2-over-N2(CH4) selectivity can be further enhanced kinetically by replacing Na+ in the 8-ring windows that control gas diffusion with large cations. In this study, samples of zeolite |Na12–xKx|-A with x = 0.0, 0.8, 2.0, and 3.0 were prepared, and the positions of adsorbed CO2 molecules were determined using in situ neutron powder diffraction through profile refinement. Adsorbed CO2 molecules were located at three different sites within the large α-cavities in the zeolite structure, revealing the interaction between the adsorbed CO2 and the host framework. The number of CO2 molecules at each site depends on CO2 pressure and follows site-specific CO2 isotherms described with a Langmuir model. Most of the CO2 molecules in zeolite |Na12–xKx|-A bridge two cations at neighboring 8-ring sites. These are relatively weakly physisorbed, and therefore, most of the working capacity of CO2 adsorption is related to this site. The CO2 molecules at the second most pop...

UV-assisted advanced oxidation processes (AOPs) are promising for the removal of microcystin-LR (MC-LR), one of cyanotoxins released during harmful algal blooms. Nevertheless, the efficiency and potential of the photo-Fenton-like process (UV-C/Fe(III)/H2O2) in treating MC-LR have not been explored in much detail. In this study, MC-LR degradation efficiencies of various UV-assisted AOPs were compared that they were higher in the order: UV-C/Fe(III)/H2O2 > UV-C/Fe(II)/H2O2 > UV-A/TiO2 > UV-C/H2O2 > UV-C > UV-A/Fe(II)/H2O2 > UV-A/H2O2 > UV-A. The concentrations of Fe(III) and H2O2 used in the photo-Fenton-like process were varied to evaluate their influences on MC-LR degradation in both deionized water and a water sample from Nak-Dong River, Daegu (South Korea). The highest removal efficiency (>80%) for MC-LR was achieved after 15 min by the photo-Fenton process at a low optimum Fenton reagent concentration (Fe = 0.5 mg L−1 and H2O2 = 1 mg L−1) in the river water. Twelve transformation products of MC-LR were identified with 1029.5, 1012.5, 1015.5, 1011.5, 965.6, 835.5, 815.4 and 783.4 m/z (two products) with the presence of four reaction sites: the conjugated diene bond of Adda, the methoxy group of Adda, the C C bond of Mdha, and the acid group of MeAsP. Theses alleviated the hepatotoxicity of MC-LR, as indicated by a protein phosphatase (PP) 2A assay. Considering the impacts of the chemistry for the treatment of river water, natural organic matter has a slightly higher impact on MC-LR degradation than the initial pH and alkalinity. The kMC-LR were maintained at 0.167–0.187 min−1 and t1/2 (min), obtained from the different river water samples, were all within 5 min in spite of the relatively high dissolved organic carbon concentrations.

Adsorption technologies offer opportunities to remove CO2 from gas mixtures, and zeolite A has good properties that include a high capacity for the adsorption of CO2. It has been argued that its abilities to separate CO2 from N2 in flue gas and CO2 from CH4 in raw biogas can be further enhanced by replacing Na+ with K+ in the controlling pore window apertures. In this study, several compositions of |Na12–xKx|-A were prepared and studied with respect to the adsorption of CO2, N2, and CH4, and the detailed structural changes were induced by the adsorption of CO2. The adsorption of CO2 gradually decreased on an increasing content of K+, whereas the adsorption of N2 and CH4 was completely nulled already at relatively small contents of K+. Of the studied samples, |Na9K3|-A exhibited the highest CO2 over N2/CH4 selectivities, with α(CO2/N2) > 21 000 and α(CO2/CH4) > 8000. For samples with and without adsorbed CO2, analyses of powder X-ray diffraction (PXRD) data revealed that K+ preferred to substitute Na+ at t...

The nonadiabatic coupling terms (NACTs, Fij’s) between triplet electronic states can be well approximated with a very simple equation suggested recently [J. Chem. Phys. 146, 064107 (2017)], using only adiabatic potential energies ( V i a and V j a ). Furthermore, the second-order differentiation can be evaluated accurately from the energy gaps, ( V i a - V j a ) , at just three consecutive geometries, even at a point exhibiting severe singularity in the behaviour of NACTs. The performance of this approximation method was investigated for the couplings between the 3 3 Π and 4 3 Π states of NaK, between the 1 3 B 3 u and 2 3 B 3 u states of N2, and between the 2 3 A ″ and 3 3 A ″ states of methylene (CH2).

Urban particles were investigated using a single particle aerosol mass spectrometer (SPAMS) in Chongqing during the summertime (from 07/05/2014 to 08/06/2014). Chemical composition, mixing state, and atmospheric behavior of urban particles were studied. The major particle types include ECOC (Elemental-Carbon-Organic-Carbon 20.6%), OC (20.1%), KSec (K-Secondary) (13.3%), BB (Biomass burning, 11.9%), NaK (sodium-potassium-rich, 7.3%), Al-rich (4.0%), Fe-rich (3.2%), Ca-rich (1.4%), Ca-EC (1.6%), and NaKPb (0.5%). EC, ECOC, OC, and Ca-EC were prevalent in the condensation mode ( Fe-rich > EC > Ca-EC > Ca-rich > KSec > OC > NaK > ECOC > Al-rich > BB. Increased number fraction of EC and KSec were correlated with the increase of odd oxygen (O x = O 3 + NO 2 ). EC, OC, and ECOC were enriched at higher relative humidity. The findings of this study on the mixing state, temporal variation, processing, and evolution of single particles provide new insight into the atmospheric behavior and impacts of urban particles.

[Image: see text] Inhibitors based on a 3-acylaminoindazole scaffold were synthesized to yield potent dual AAK1/BMP2K inhibitors. Optimization furnished a small molecule chemical probe (SGC-AAK1-1, 25) that is potent and selective for AAK1/BMP2K over other NAK family members, demonstrates narrow activity in a kinome-wide screen, and is functionally active in cells. This inhibitor represents one of the best available small molecule tools to study the functions of AAK1 and BMP2K.

Inhibitors based on a 3-acylaminoindazole scaffold were synthesized to yield potent dual AAK1/BMP2K inhibitors. Optimization of this 3-acylaminoindazole scaffold furnished a small molecule chemical probe (SGC-AAK1-1, 25) that is potent and selective for AAK1/BMP2K over other NAK family members, demonstrates narrow activity in a kinome-wide screen, and is functionally active in cells. This inhibitor represents one of the best available small molecule tools to study the functions of AAK1 and BMP2K.

The EA-EOM (electron-attachment equation-of-motion) coupled cluster approach provides a description of the states obtained by attachment of a single electron to the reference system. If the reference is assumed to be a doubly ionized cation then the results relate to the cation. In the current work the above scheme is applied to the calculations of potential energy curves for the LiK+ and NaK+ molecular ions adopting as a reference system the doubly ionized structure, i.e., LiK+2 and NaK+2. Such computational strategy benefits from the fact that the closed shell reference (LiK+2 or NaK+2) dissociates into the closed shell fragments (LiK + 2 ⇒ Li+ + K+, NaK + 2 ⇒ Na+ + K+). This is advantageous since the RHF (restricted Hartree–Fock) function can be used as a reference in the whole range of interatomic distances. This scheme offers a first principle method without any model or effective potential parameters for the description of the bond-breaking processes. Moreover, the scalar relativistic effects are included by adding appropriate terms of the DK (Douglas–Kroll) Hamiltonian to the one-electron integrals.

In this study the releasing of nutrients from sediments of Nak-dong River were investigated. We perfomed lab-scale simulation experiments using field sediment and ware. Nutrients, orgarni matter, particle size of the sediments and nutrients of released water were analyzed. Analyzed results of the sediments, mainly composed of mS(muddy Sand) sedimentary facies and IL were 2.46~6.83%, T-N were 1.189~2.492mg/kg, and T-P were 333~726mg/kg in the study area. Analyzed results of the nutrients of released water, pH and TOC were each 7.8~9.2% and 31.7~40.8% decreased after 20 days. T-N increased steadily, and NH 3 -N increased steadily then decreased, at this time NO 3 -N increase. Also NH 3 -N increased steadily, then decreased at this time. Furthermore release of phosphorus were mostly decreased.Key words:Nak-dong River, Nutrient, Phosphorus, Sediment, Release, Water quality 1.Introduction 1)다양한경로를통해수계로유입되는오염물질은최종적으로퇴적물에축적된다. 유역으로부터유입되어수저에쌓이는모래, 점토, 유기물질, 광물질등의퇴적물은하상의변화와유속의저하에의해운반력이약화된곳에쌓이거나화학적으로침전되는것으로이러한퇴적물의이동과퇴적은주로유수에의해일어난다. 특히우리나라의하천과같이강우에의한유량변동이큰수계는집중강우시많은양의퇴적물이하천하류나호소바닥층으로이동하여축적되고, 이과정에서홍수나준설등으로인해퇴적물이재부유, 침식, 교란등의활동에의해오염물질이용출되어하천및호소의수질에심각한영향을미칠수있다(NIER, 2012).우리나라는기후변화에따른수해예방과부족한수자원확보를위해2011년부터4대강의정비사업을실시하였고, 그일환으로4대강에16개의보가건설되었다(MOLIT, 2009). 그러나이와같이하천의체류시간을늘려유량을확보하

Samples of powdered zeolite LSX are synthesized that are characterized by high phase purity and a crystallinity degree close to 100% in NaK, K, Na, and Li forms. XRD and adsorption methods were used to elucidate the effect of the chemical nature and content of the exchange cation on the phase composition and characteristics of the porous structure and the thermal stability of the above forms of zeolite LSX.

The fluorescent unnatural amino acid, (7-hydroxycoumarin-4-yl)ethylglycine (HC), was site-specifically incorporated at the Phe69 site, close to the entrance of the selectivity filter of the NaK channel. Decreased fluorescence lifetime and elevated time-resolved anisotropy of NaK-F69HC in buffers with high K(+)/Na(+) molar ratios indicated the K(+) preference at the entrance of the NaK channel, consistent with previous crystal structure results of the NaK channel.

4-Anilinoquinolines were identified as potent and narrow-spectrum inhibitors of the cyclin G associated kinase (GAK), an important regulator of viral and bacterial entry into host cells. Optimization of the 4-anilino group and the 6,7-quinoline substituents produced GAK inhibitors with nanomolar activity, over 50 000-fold selectivity relative to other members of the numb-associated kinase (NAK) subfamily, and a compound (6,7-dimethoxy-N-(3,4,5-trimethoxyphenyl)quinolin-4-amine; 49) with a narrow-spectrum kinome profile. These compounds may be useful tools to explore the therapeutic potential of GAK in prevention of a broad range of infectious and systemic diseases.

The double cation borohydrides NaK(BH 4 ) 2 has a total H 2 content of 8.8 wt.% and has suggested as a potential candidate for hydrogen storage applications. The four decomposition reaction paths associated with NaK(BH 4 ) 2 are predicted to reaction thermodynamics for hydrogen release within the temperature range of 21–126 °C. However, a critical drawback with first-principles is that the predicted reaction mechanism might not be the most stable reaction path. The aim of this study is to provide an answer to this problem by examining possible metastable paths for four reactant mixtures whose reaction mechanisms were previously predicted using first principles thermodynamics calculations.

Expressed protein ligation (EPL) is a semisynthetic technique for the chemoselective ligation of a synthetic peptide to a recombinant peptide that results in a native peptide bond at the ligation site. EPL therefore allows us to engineer proteins with chemically defined, site-specific modifications. While EPL has been used mainly in investigations of soluble proteins, in recent years it has been increasingly used in investigations of integral membrane proteins. These include studies on the KcsA K(+) channel, the non-selective cation channel NaK, and the porin OmpF. These studies are discussed in this review.

The Na + and K + channels are essential to neural signaling, but our current knowledge at the atomic level is mainly limited to the conducting mechanism of K + . Unlike a K + channel having four equivalent K + -binding sites in its selectivity filter, a NaK channel has a vestibule in the middle part of its selectivity filter, and can conduct both Na + and K + ions. However, the underlying mechanism for non-selective ion conduction in NaK remains elusive. Here we find four small grottos connecting with the vestibule of the NaK selectivity filter, which form a vestibule-grotto complex perpendicular to the filter pore with a few water molecules within it. It is shown that two or more of the water molecules coming to the vestibule to coordinate the cation are necessary for conducting both Na + and K + ions, while only one water molecule in the vestibule will obstruct ion permeation. Thus, the complex with the aid of interior water movement forms a dynamic hydration valve which is flexible in conveying different cations through the vestibule. Similar exquisite hydration valve mechanisms are expected to be utilized by other non-selective cation channels, and the results should shed new light on the importance of water in neural signaling.

A parameter-free analytical formula for dissociation energies of diatomic molecules is proposed by Fan and Sun (2009) [20] based on LeRoy and Bernstein's vibrational energy expression near dissociation limit. Using three highest vibrational energies which may be generated by the algebraic method (AM) presented in our previous study and by some other physical methods, the new formula is applied to study the molecular dissociation energies of 10 electronic states of KH, (7)LiD, (7)LiH, (6)LiH, NaK, NaLI and NaRb heteronuclear diatomic molecules which have regular (Morse-like) potentials in this work. The results show that the AM energies E(upsilon)(AM) and dissociation energies D(e)(AM) have excellent agreement with experimental values.

How K(+) channels are able to conduct certain cations yet not others remains an important but unresolved question. The recent elucidation of the structure of NaK, an ion channel that conducts both Na(+) and K(+) ions, offers an opportunity to test the various hypotheses that have been put forward to explain the selectivity of K(+) ion channels. We test the snug-fit, field-strength, and over-coordination hypotheses by comparing their predictions to the results of classical molecular dynamics simulations of the K(+) selective channel KcsA and the less selective channel NaK embedded in lipid bilayers. Our results are incompatible with the so-called strong variant of the snug-fit hypothesis but are consistent with the over-coordination hypothesis and neither confirm nor refute the field-strength hypothesis. We also find that the ions and waters in the NaK selectivity filter unexpectedly move to a new conformation in seven K(+) simulations: the two K(+) ions rapidly move from site S4 to S2 and from the cavity to S4. At the same time, the selectivity filter narrows around sites S1 and S2 and the carbonyl oxygen atoms rotate 20 degrees -40 degrees inwards toward the ion. These motions diminish the large structural differences between the crystallographic structures of the selectivity filters of NaK and KcsA and appear to allow the binding of ions to S2 of NaK at physiological temperature.

Sodium and its alloys such as sodium-potassium (NaK) have been used or considered as coolants in nuclear reactors, including space reactor systems. One potentially serious problem of using...

The total resistivity for the NaK, NaRb and NaCs alkali alloys was divided into partial resistivities and calculated by means of Zimans’s formula within a simplified and semi-empirical approach. It is shown that the height of the parabolic resistivity behavior versus concentration is related to the scattering potential whereas the position of the maximum depends on the structure of liquid. Further it appears clearly that the leading contribution is due to the sodium as a result of its muffin tin zero enhancement with respect to its value in the pure liquid phase.

Single- and few-layer MoS2, WS2, and BN nanosheets are prepared through intercalation and exfoliation using liquid NaK or NaLi alkali metal alloys in DME at room temperature for 24—48 h.

Irradiation tests of materials at HANARO have usually been conducted using a standard capsule at temperatures of about 300°C for irradiation of materials used at PWR. Thus, the standard capsule uses aluminum as the specimen holder, which acts to dissipate the thermal energy. Future nuclear systems such as a VHTR and SFR require the irradiation tests at a relatively high temperature. As an alternative to aluminum which has been used as the thermal media in a standard material capsule, the characteristics of liquid metals such as NaK and LBE are reviewed. The temperatures of the capsule are affected by the variation of parameters such as the gap and wall thickness of the container. In particular, the external gap is most important in determining the temperature of the specimen. LBE raises the temperature of the specimen higher than NaK at the same configuration of the capsule. Thus, LBE can lessen the gap of the parts and reduce the vibration for a stable long-term test in reactor.

The Os−Os dimer [Cp(CO)2Os]2 was synthesized in good yield by reaction of Cp(CO)2OsI with NaK. The related Cp* dimer [Cp*(CO)2Os]2 (Cp* = η5-C5Me5) was prepared by reaction of Cp*(CO)2OsH with 2,2‘-azobis(isobutyrylnitrile) (AIBN). In contrast to [Cp(CO)2Os]2, which has only terminal CO ligands, spectroscopic and crystallographic data indicate that [Cp*(CO)2Os]2 has two bridging CO ligands. Reaction of tetraisopropylcyclopentadiene with [(CO)3OsI]2 provides (iPr4C5H)(CO)2OsI, which can be converted to (iPr4C5H)(CO)2OsH through reduction with NaK followed by treatment with EtOH. Reaction of (iPr4C5H)(CO)2OsH with AIBN gives [(iPr4C5H)(CO)2Os]2, which is much more soluble than [Cp*(CO)2Os]2. DFT (B3LYP) calculations on these Os−Os dimers reveal the energetics of different geometrical isomers. The anti and gauche isomers of [Cp(CO)2Os]2, with terminal CO ligands, are significantly more stable than the trans and cis isomers with bridging CO ligands, while the stability of the anti isomer of [Cp*(CO)2Os]2 is s...

We report a good agreement between the shapes of tailored pulses obtained theoretically and experimentally by using the optimal-control theory and the closed-loop learning technique to maximize the ionization yield in NaK. The theoretical pulse shapes are found to be robust regarding the choice of the initial guess. We assign the leading features of the pulse shapes to processes underlying the optimal control and reveal the mechanism which involves an electronic transition followed by a direct two-photon process and sequential one-photon processes at later times. We show that the optimal control not only serves for maximizing the desired yield but also as a tool for the analysis and the identification of the responsible processes.

The 4 1 Σ + state of NaK molecule has been observed for the first time and studied by polarisation labelling spectroscopy technique. A total of 1567 rovibronic levels in this state were measured with an accuracy better than 0.1 cm −1 . The inverted perturbation approach method was used to construct the potential energy curve of the 4 1 Σ + state. The irregular shape of the potential confirms earlier theoretical predictions.

Polarization labelling spectroscopy is applied to study the previously unobserved 5 1 Σ + state of the NaK molecule. Molecular constants and a Rydberg–Klein–Rees (RKR) potential energy curve based on these constants are determined. The values of Te, ωe and Re are 23530.62(6) cm−1, 115.60(6) cm−1 and 4.307 A, respectively.

Studies of the non-selective NaK channel as a model system provided detailed structural and functional insights into different factors that modulate selective ion conductance. The combination of structural and functional studies of WT- and mutant forms of NaK channel show that apparent conservation of the multiple binding sites in the canonical selectivity filter of K-channel is essential component of the observed robust Na+ discrimination.Commentary to: Derebe GM, Sauer DB, Zeng W, Alam A, Shi N, Jiang Y. Tuning the ion selectivity of tetrameric cation channels by changing the number of the ion binding sites. Proc Natl Acad Sci USA 2011; 108:598-602; PMID: 21187421; DOI: 10.1073/pnas.1013636108.AND

Flower development of the lateral buds was accelerated in Japanese pear [Pyrus pyrifolia (Burm.) Nak.] when vertical shoots were bent at a 45° angle in late June. The indole-3-acetic acid (IAA) concentration in lateral buds on vertical (control) shoots increased in mid-July, while remaining nearly constant in bent shoots. The abscisic acid (ABA) concentration of buds in bent shoots rose between 4 July and 15 Aug., whereas control shoots exhibited an increase in concentration followed by a decline. Gibberellin4+7 (GA4+7) concentration was high on 16 June, and then declined by 4 July, with the decline being greatest in bent shoots. Gibberellin4+7 concentration was higher in the buds on vertical shoots than in those on bent shoots for much of July. The concentrations of zeatin-type cytokinins (CKs) in lateral buds were higher in bent shoots than in vertical shoots. Bending of pear shoots may weaken competition between buds and other organs through altering hormone levels in lateral buds, resulting in acceleration of flower development.

The 41Π and 51Π states of the NaK molecule have been investigated experimentally by polarization labelling spectroscopy technique and theoretically within the framework of the ab initio pseudopotential method. A very good agreement has been obtained between the calculated potential curves and those determined from experimental observations.

This article reports the observation of the molecular fluorescence circularity under irradiation with linearly polarised light. This alignment-orientation conversion phenomenon arises as a result of partial transformation from alignment of the ensemble of 1 P state molecular angular momenta into their orientation under the effect of non-linear dc Stark effect. Circularity rate up to 0.12 was observed in D 1 P! X 1 S fluorescence of 23 Na 39 K molecules in agreement with the theoretically predicted value.

A combined experimental and theoretical study of the vibrational wave packet dynamics for the NaK molecule in the A (1)Sigma(+) state is presented. The experiment utilises a 790 nm one-colour fem ...

We report here the application of optical-radio frequency double resonance spectroscopy for individual rotational levels of the NaK D 1 Π state. Lambda doubling constant q values for five ν′, J ′ levels are obtained. These data are combined with measurements of dc e - f Stark-mixing-induced changes in optical spectra, and the electric dipole moment d p in the D 1 Π state is determined.

The real-time vibrational dynamics of NaK molecules excited to the electronic A1∑+ state has been studied isotipe-selectively by means of time-resolved three-photon ionization. For 23Na39K and 23Na41K vibrational periods of T A (23,39) ≊ 441 fs and T A (23,41) ≊446 fs are determined. A detailed Fourier analysis proofs a weak perturbation of the wave packet caused by spin-orbit coupling of A and b3ν states. Pronounced fractional revivals of the fundamental oscillation occur at T frev 1,2(23,39) ≊ 75 ps and T frev 1,2(23,41) ≊ 68 ps . Spectrograms of the real-time data nicely reveal a strong fractional revival at T frev 1,4 = 1 2 T frev 1,2 . Further revivals of weaker intensity at Tfrev1,6(23,39) ≈ 25 ps and Tfrev1,3(23,39) ≈ 50 ps are found for the lighter isotope.

The J‘ dependencies of energy and line width of the 23Na39K B1Π(v‘ = 30−43, J‘) ← X1Σ+(v‘ ‘ = 2, J‘ ‘) transitions are measured up to the breaking-off points, where NaK dissociates to the Na(3s2S1/2) + K(4p2P3/2) atoms. Line broadenings are observed for transitions to the B1Π(v‘ = 30, J‘ ≥ 42), (v‘ = 31, J‘ ≥ 35), (v‘ = 32, J‘ ≥ 27), (v‘ = 33, J‘ ≥ 14), and (v‘ ≥ 34, all J‘) levels, and are attributed to the predissociation via the c3Σ+ state to the Na(3s2S1/2) + K(4p2P1/2) atoms. The (v‘, J‘) dependence of the predissociation threshold is attributed to the potential barrier due to rotation. Below and near the threshold, a series of the perturbation centers which converge to the predissociation threshold is observed for each v‘, and the perturbing state is identified as the c3Σ+ state. Rotational perturbations are observed also above the predissociation threshold, and the perturbing state is identified as the b3Π1 state. The line widths are observed to change drastically around the maximum perturbation, a...

Potassium (K(+)) channels are selective for K(+) over Na(+) ions during their transport across membranes. We and others have previously shown that tetrameric K(+) channels are primarily occupied by K(+) ions in their selectivity filters under physiological conditions, demonstrating the channel's intrinsic equilibrium preference for K(+) ions. Based on this observation, we hypothesize that the preference for K(+) ions over Na(+) ions in the filter determines its selectivity during ion conduction. Here, we ask whether non-selective cation channels, which share an overall structure and similar individual ion-binding sites with K(+) channels, have an ion preference at equilibrium. The variants of the non-selective Bacillus cereus NaK cation channel we examine are all selective for K(+) over Na(+) ions at equilibrium. Thus, the detailed architecture of the K(+) channel selectivity filter, and not only its equilibrium ion preference, is fundamental to the generation of selectivity during ion conduction.

We report the observation of the c 3Σ+→a 3Σ+ emission in NaK following excitation of single rovibronic levels in the c 3Σ+ state. The dispersed fluorescence displays both diffuse and discrete features. The characteristic reflection structure of the bound–free spectra permits a direct, unambiguous assignment of the vibrational numbering in the c 3Σ+ state: The v=20 level is the first vibrational level of c 3Σ+ lying above v=0 in the B 1Π state. The c 3Σ+ state potential curve is determined from bound–free parts of the observed spectra with the inversion procedure of LeRoy et al. [J. Chem. Phys. 89, 4564 (1988)]; its most important parameters are Te=15 857±15 cm−1 and Re=0.445±0.001 nm.

Nak Kwan Sung, Eun Soo Park President of the the Korean Toxin-Filler Research Association of Plastic & Reconstructive Surgeons, SungNakKwan Plastic Surgery, Seoul; 2 Manager of the the Korean Toxin-Filler Research Association of Plastic & Reconstructive Surgeons, Department of Plastic and Reconstructive Surgery, College of Medicine, Soonchunhyang University, Bucheon, Korea LETTER http://dx.doi.org/10.14730/aaps.2016.22.1.47 Arch Aesthetic Plast Surg 2016;22(1):47-48 pISSN: 2234-0831 eISSN: 2288-9337

This paper concerns the thermo-hydraulic simulations of a helium-cooled solid specimen stack within the High Flux Test Module of IFMIF (International Fusion Materials Irradiation Facility). Three cases were studied: 1) the gap between specimens is filled with NaK; 2) the gap between specimens is filled with helium; 3) specimens and NaK-filling are taken as a single solid block with homogeneous properties.

The approximate sum rule ≈ Σv2 (Ev1 - Ev2)n, where f, g are operators which couple the vibrational levels v1, v2 of two interacting electronic states and ΔU=U1—U2 is the difference of the corresponding internuclear potentials, is numerically tested for radiative lifetimes, electronic polarizabilities, fine-structure constants and Lande factors for the vibronic states of the NaK molecule. The approximation is demonstrated to have high accuracy and efficiency for non-diagonal systems, especially for those with significant continuum contributions. Simple ways of estimating the sum rule accuracy are given.

Vibrational levels near the dissociation limit of NaK a 3Σ+ state are observed with an optical–optical double resonance technique. High resolution spectra are sensitively detected with the combination of perturbation facilitated polarization spectroscopy with frequency modulation spectroscopy. An electronically excited state, the B 1Π state, is mixed with the c 3Σ+ state through spin–orbit interaction. The transition from the X 1Σ+ state to the a 3Σ+ state through the B 1Π state is facilitated by the perturbation by the c 3Σ+ state. Hyperfine structures of the a 3Σ+(v=3−16,N=4−25) state are resolved with this spectroscopic technique and found to be independent of vibrational and rotational quantum number. The a 3Σ+ state can only be perturbed by the X 1Σ+ state through the hyperfine interaction. The vibrational levels (v≤16) of the a 3Σ+ state are demonstrably not perturbed by the X 1Σ+ state. The potential curve of the a 3Σ+ state is determined by the near‐dissociation expansion fitting of molecular con...